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English Pages 1271 [1296] Year 2013
Emergency Medicine Procedures
NOTICE Medicine is an ever-changing science. As new research and clinical experience broaden our knowledge, changes in treatment and drug therapy are required. The authors and the publisher of this work have checked with sources believed to be reliable in their efforts to provide information that is complete and generally in accord with the standards accepted at the time of publication. However, in view of the possibility of human error or changes in medical sciences, neither the editors nor the publisher nor any other party who has been involved in the preparation or publication of this work warrants that the information contained herein is in every respect accurate or complete, and they disclaim all responsibility for any errors or omissions or for the results obtained from use of the information contained in this work. Readers are encouraged to confirm the information contained herein with other sources. For example and in particular, readers are advised to check the product information sheet included in the package of each drug they plan to administer to be certain that the information contained in this work is accurate and that changes have not been made in the recommended dose or in the contraindications for administration. This recommendation is of particular importance in connection with new or infrequently used drugs.
Emergency Medicine Procedures Second Edition Eric F. Reichman, PhD, MD, FAAEM, FACEP Associate Professor of Emergency Medicine Attending Physician, Department of Emergency Medicine Medical Director, Surgical and Clinical Skills Center University of Texas Health Science Center at Houston-Medical School Attending Physician, Emergency Department Memorial Hermann Hospital-Texas Medical Center Attending Physician, Emergency Department Lyndon Baines Johnson General Hospital Houston, Texas
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Copyright © 2013 by Eric F. Reichman, PhD, MD. All rights reserved. Except as permitted under the United States Copyright Act of 1976, no part of this publication may be reproduced or distributed in any form or by any means, or stored in a database or retrieval system, without the prior written permission of the editor. ISBN: 978-0-07-161351-4 MHID: 0-07-161351-X The material in this eBook also appears in the print version of this title: ISBN: 978-0-07-161350-7, MHID: 0-07-161350-1. All trademarks are trademarks of their respective owners. Rather than put a trademark symbol after every occurrence of a trademarked name, we use names in an editorial fashion only, and to the benefit of the trademark owner, with no intention of infringement of the trademark. Where such designations appear in this book, they have been printed with initial caps. McGraw-Hill Education eBooks are available at special quantity discounts to use as premiums and sales promotions, or for use in corporate training programs. To contact a representative please e-mail us at [email protected]. TERMS OF USE This is a copyrighted work and McGraw-Hill Education, LLC. and its licensors reserve all rights in and to the work. Use of this work is subject to these terms. Except as permitted under the Copyright Act of 1976 and the right to store and retrieve one copy of the work, you may not decompile, disassemble, reverse engineer, reproduce, modify, create derivative works based upon, transmit, distribute, disseminate, sell, publish or sublicense the work or any part of it without McGraw-Hill Education’s prior consent. You may use the work for your own noncommercial and personal use; any other use of the work is strictly prohibited. Your right to use the work may be terminated if you fail to comply with these terms. THE WORK IS PROVIDED “AS IS.” McGRAW-HILL EDUCATION AND ITS LICENSORS MAKE NO GUARANTEES OR WARRANTIES AS TO THE ACCURACY, ADEQUACY OR COMPLETENESS OF OR RESULTS TO BE OBTAINED FROM USING THE WORK, INCLUDING ANY INFORMATION THAT CAN BE ACCESSED THROUGH THE WORK VIA HYPERLINK OR OTHERWISE, AND EXPRESSLY DISCLAIM ANY WARRANTY, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. McGraw-Hill Education and its licensors do not warrant or guarantee that the functions contained in the work will meet your requirements or that its operation will be uninterrupted or error free. Neither McGraw-Hill Education nor its licensors shall be liable to you or anyone else for any inaccuracy, error or omission, regardless of cause, in the work or for any damages resulting therefrom. McGraw-Hill Education has no responsibility for the content of any information accessed through the work. Under no circumstances shall McGraw-Hill Education and/or its licensors be liable for any indirect, incidental, special, punitive, consequential or similar damages that result from the use of or inability to use the work, even if any of them has been advised of the possibility of such damages. This limitation of liability shall apply to any claim or cause whatsoever whether such claim or cause arises in contract, tort or otherwise.
To my wife, Kristi. hanks for your patience with the semi-permanent card table and computer in the living room, and the mess with all the papers and iles. hanks for your support and understanding. hanks to Joey, Jake, Rocky, and Phoebe for entertaining me each day.
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Contents Contributors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xiii Preface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xxiii
18 Supraglottic Airway Devices . . . . . . . . . . . . . . . . . . . 106 Fred A. Severyn
Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xxiv
19 Laryngeal Mask Airways . . . . . . . . . . . . . . . . . . . . . 110 Katrin Takenaka and Theltonia Howard
SECTION 1 Introductory Chapters . . . . . . . . . . . . . . . . 1
20 Double Lumen Airway Tube Intubation . . . . . . . . . . . . 122 Joseph Weber
1 Informed Consent for Procedures in the Emergency Department . . . . . . . . . . . . . . . . . . . 1 Eric Isaacs
21 Fiberoptic Endoscopic Intubation . . . . . . . . . . . . . . . 127 Erika D. Schroeder, M. Scott Linscott, and Joseph Bledsoe
2 Aseptic Technique . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 John S. Rose
22 Nasotracheal Intubation . . . . . . . . . . . . . . . . . . . . . 134 Ned F. Nasr, Raed Rahman, and Isam F. Nasr
3 Basic Principles of Ultrasonography . . . . . . . . . . . . . . . 13 Gregory M. Press
23 Retrograde Guidewire Intubation . . . . . . . . . . . . . . . 139 Roland Petri
4 Ultrasound-Assisted Procedures . . . . . . . . . . . . . . . . . 24 Jehangir Meer, Sam Hsu, and Brian Euerle
24 Percutaneous Transtracheal Jet Ventilation . . . . . . . . . . 143 Eric F. Reichman and Aaron Brown
5 Trauma Ultrasound: The FAST Exam . . . . . . . . . . . . . . . 28 Wes Zeger
25 Cricothyroidotomy . . . . . . . . . . . . . . . . . . . . . . . . 148 Eric F. Reichman
SECTION 2 Respiratory Procedures . . . . . . . . . . . . . . 35
26 Tracheostomy . . . . . . . . . . . . . . . . . . . . . . . . . . . 161 Teresa M. Romano and Christopher J. Haines
6 Essential Anatomy of the Airway . . . . . . . . . . . . . . . . 35 Ned F. Nasr, Serge G. Tyler, Gennadiy Voronov, and Isam F. Nasr 7 Basic Airway Management . . . . . . . . . . . . . . . . . . . . 40 Christopher J. Russo and Zach Kassutto 8 Pharmacologic Adjuncts to Intubation. . . . . . . . . . . . . . 47 Ned F. Nasr, David W. Boldt, and Isam F. Nasr 9 Endotracheal Medication Administration . . . . . . . . . . . . 56 Shoma Desai 10 Rapid Sequence Induction . . . . . . . . . . . . . . . . . . . . . 60 Piotr C. Aljindi, Ned F. Nasr, and Isam F. Nasr 11 Orotracheal Intubation . . . . . . . . . . . . . . . . . . . . . . . 64 Eric F. Reichman and Joseph Cornett 12 Confirmation of Endotracheal Intubation . . . . . . . . . . . . 76 Tarlan Hedayati and Leonardo Rodriguez 13 Video-Assisted Orotracheal Intubation Devices . . . . . . . . 80 Pholaphat Charles Inboriboon 14 Fiberoptic-Assisted Orotracheal Intubation Devices . . . . . 89 Michael Lutes and Olga Pawelek
27 Tracheostomy Care . . . . . . . . . . . . . . . . . . . . . . . . 171 H. Gene Hern Jr. 28 Transtracheal Aspiration . . . . . . . . . . . . . . . . . . . . . 177 Joseph A. Salomone III
SECTION 3 Cardiothoracic Procedures . . . . . . . . . . . 181 29 Cardiac Ultrasound . . . . . . . . . . . . . . . . . . . . . . . . 181 Gregory M. Press and Amy Rasmussen 30 Cardioversion and Defibrillation . . . . . . . . . . . . . . . . 193 Payman Sattar 31 Transcutaneous Cardiac Pacing . . . . . . . . . . . . . . . . . 197 Todd M. Larabee 32 Transthoracic Cardiac Pacing . . . . . . . . . . . . . . . . . . 202 Simon M. Pulfrey 33 Transvenous Cardiac Pacing. . . . . . . . . . . . . . . . . . . 205 Eric F. Reichman, Myles C. McClelland, and Brian Euerle 34 Pacemaker Assessment . . . . . . . . . . . . . . . . . . . . . 212 Nnaemeka G. Okafor
15 Endotracheal Tube Intubating Introducers and Bougies . . . 95 Olga Pawelek and Eric F. Reichman
35 Automatic Implantable Cardioverter-Defibrillator Assessment. . . . . . . . . . . . . 218 Carlos J. Roldan
16 Digital (Tactile) Orotracheal Intubation . . . . . . . . . . . . 100 O. John Ma and Amanda Munk
36 Pericardiocentesis . . . . . . . . . . . . . . . . . . . . . . . . . 225 Eric F. Reichman, Elisabeth Kang, and Jehangir Meer
17 Lighted Stylet Intubation . . . . . . . . . . . . . . . . . . . . . 102 Philip Bossart and Michael Wallace
37 Intracardiac Injection . . . . . . . . . . . . . . . . . . . . . . . 236 Payman Sattar vii
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Contents
38 Needle Thoracostomy . . . . . . . . . . . . . . . . . . . . . . 238 Eric F. Reichman and Elizabeth Sowell
61 Whole Bowel Irrigation. . . . . . . . . . . . . . . . . . . . . . 398 Steven E. Aks and David D. Gummin
39 Tube Thoracostomy . . . . . . . . . . . . . . . . . . . . . . . . 242 Kimberly T. Joseph
62 Esophageal Foreign Body Removal . . . . . . . . . . . . . . 401 Bashar M. Attar
40 Thoracentesis . . . . . . . . . . . . . . . . . . . . . . . . . . . 250 Eric F. Reichman, Cristal R. Cristia, and Jehangir Meer
63 Balloon Tamponade of Gastrointestinal Bleeding . . . . . . 407 Bashar M. Attar
41 Open Chest Wound Management . . . . . . . . . . . . . . . 263 Eric F. Reichman
64 Gastrostomy Tube Replacement . . . . . . . . . . . . . . . . 414 Maggie Ferng and Ryan C. Headley
42 Emergency Department Thoracotomy . . . . . . . . . . . . 267 Kenny Banh
65 Paracentesis . . . . . . . . . . . . . . . . . . . . . . . . . . . . 421 Susan B. Promes, Elizabeth M. Datner, and Sam Hsu
43 Open Cardiac Massage. . . . . . . . . . . . . . . . . . . . . . 271 Eric F. Reichman
66 Diagnostic Peritoneal Lavage . . . . . . . . . . . . . . . . . . 431 Sandeep Johar and Umashankar Lakshmanadoss
44 Cardiac Wound Repair . . . . . . . . . . . . . . . . . . . . . . 274 Eric F. Reichman
67 Anal Fissure Management . . . . . . . . . . . . . . . . . . . . 439 Marilyn M. Hallock and Eric F. Reichman
45 Hilum and Great Vessel Wound Management . . . . . . . . 280 Eric F. Reichman
68 External Hemorrhoid Management . . . . . . . . . . . . . . 443 Charles Orsay and Eric F. Reichman
46 Thoracic Aortic Occlusion . . . . . . . . . . . . . . . . . . . . 282 Eric F. Reichman
69 Prolapsed Rectum Reduction . . . . . . . . . . . . . . . . . . 446 Jamil D. Bayram and Eric F. Reichman
SECTION 4 Vascular Procedures . . . . . . . . . . . . . . . . 287
70 Anoscopy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 449 Charles Orsay and Eric F. Reichman
47 General Principles of Intravenous Access . . . . . . . . . . . 287 Daniel Belmont
71 Rigid Rectosigmoidoscopy . . . . . . . . . . . . . . . . . . . . 453 Charles Orsay and Eric F. Reichman
48 Venipuncture and Peripheral Intravenous Access . . . . . . 296 Daniel Belmont
72 Rectal Foreign Body Extraction . . . . . . . . . . . . . . . . . 458 Charles Orsay and Eric F. Reichman
49 Central Venous Access . . . . . . . . . . . . . . . . . . . . . . 308 Arun Nagdev and Craig Sisson 50 Ultrasound-Guided Vascular Access . . . . . . . . . . . . . . 327 Srikar Adhikari 51 Troubleshooting Indwelling Central Venous Lines. . . . . . 337 James J. McCarthy 52 Accessing Indwelling Central Venous Lines . . . . . . . . . . 340 Lisa Freeman Grossheim 53 Pulmonary Artery (Swan-Ganz) Catheterization . . . . . . 344 Pratik Doshi 54 Peripheral Venous Cutdown. . . . . . . . . . . . . . . . . . . 350 Flavia Nobay 55 Intraosseous Infusion . . . . . . . . . . . . . . . . . . . . . . . 361 Amanda Munk and O. John Ma 56 Umbilical Vessel Catheterization . . . . . . . . . . . . . . . . 369 Eric F. Reichman, Amy Noland, and Antonio E. Muñiz 57 Arterial Puncture and Cannulation . . . . . . . . . . . . . . . 376 Zak Foy and Susan Stroud
SECTION 5 Gastrointestinal Procedures . . . . . . . . . . 387 58 Nasogastric Intubation . . . . . . . . . . . . . . . . . . . . . . 387 Lisa Freeman Grossheim 59 Activated Charcoal Administration . . . . . . . . . . . . . . . 391 Jenny J. Lu 60 Gastric Lavage . . . . . . . . . . . . . . . . . . . . . . . . . . . 393 Jenny J. Lu
SECTION 6 Orthopedic and Musculoskeletal Procedures . . . . . . . . . . 465 73 Bursitis and Tendonitis Therapy . . . . . . . . . . . . . . . . 465 Dedra Tolson 74 Compartment Pressure Measurement . . . . . . . . . . . . 473 Matt Kleinmaier and Sanjeev Malik 75 Fasciotomy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 480 Justin Mazzillo, Sobia Ansari, and Eric F. Reichman 76 Extensor Tendon Repair . . . . . . . . . . . . . . . . . . . . . 490 Jaime Harper, Stanley Harper, and Ramasamy Kalimuthu 77 Arthrocentesis . . . . . . . . . . . . . . . . . . . . . . . . . . . 495 Eric F. Reichman, John Larkin, and Brian Euerle 78 Methylene Blue Joint Injection . . . . . . . . . . . . . . . . . 517 Joseph E. Tonna, Heather H. Bohn, and Matthew R. Lewin 79 Basic Principles of Fracture and Joint Reductions . . . . . . 522 Scott C. Sherman 80 Sternoclavicular Joint Dislocation Reduction . . . . . . . . . 526 Eric F. Reichman 81 Shoulder Joint Dislocation Reduction . . . . . . . . . . . . . 531 Eric F. Reichman 82 Elbow Joint Dislocation Reduction . . . . . . . . . . . . . . . 549 Angelique S. Kelly Campen 83 Radial Head Subluxation (“Nursemaid’s Elbow”) Reduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 553 Mark P. Kling and Eric F. Reichman
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84 Metacarpophalangeal Joint Dislocation Reduction . . . . . 557 Michael Bublewicz and Antonio E. Muñiz
107 Paronychia or Eponychia Incision and Drainage . . . . . . 713 Lisa R. Palivos
85 Interphalangeal Joint Dislocation Reduction . . . . . . . . . 561 Matt Kleinmaier and Sanjeev Malik
108 Felon Incision and Drainage . . . . . . . . . . . . . . . . . . 716 Lisa R. Palivos
86 Hip Joint Dislocation Reduction . . . . . . . . . . . . . . . . 565 George Chiampas and Steve Zahn
109 Pilonidal Abscess or Cyst Incision and Drainage. . . . . . . 718 Lauren M. Smith
87 Patellar Dislocation Reduction . . . . . . . . . . . . . . . . . 571 Mark P. Kling
110 Perianal Abscess Incision and Drainage . . . . . . . . . . . . 722 Maggie Ferng and Ryan C. Headley
88 Knee Joint Dislocation Reduction . . . . . . . . . . . . . . . 574 Sharad Pandit and Zach Kassutto
111 Sebaceous Cyst Incision and Drainage . . . . . . . . . . . . 728 Carlos J. Roldan
89 Ankle Joint Dislocation Reduction . . . . . . . . . . . . . . . 577 Jim Comes
112 Hemorrhage Control . . . . . . . . . . . . . . . . . . . . . . . 731 Christopher Freeman and Eric F. Reichman
90 Common Fracture Reduction . . . . . . . . . . . . . . . . . . 582 Eric F. Reichman and Robert M. Zesut
113 Trigger Point Injections . . . . . . . . . . . . . . . . . . . . . . 738 Danielle Campagne
91 Casts and Splints . . . . . . . . . . . . . . . . . . . . . . . . . 592 Eric F. Reichman and Harold A. Sloas
114 Escharotomy . . . . . . . . . . . . . . . . . . . . . . . . . . . . 741 Michael A. Schindlbeck
SECTION 7 Skin and Soft Tissue Procedures . . . . . . . 609
SECTION 8 Neurologic and Neurosurgical Procedures . . . . . . . . . . . . 747
92 General Principles of Wound Management . . . . . . . . . 609 Lisa Freeman Grossheim 93 Basic Wound Closure Techniques . . . . . . . . . . . . . . . 623 Eric F. Reichman and Candace Powell 94 Tissue Adhesives for Wound Repair . . . . . . . . . . . . . . 647 Hagop M. Afarian 95 Advanced Wound Closure Techniques . . . . . . . . . . . . 650 Eric F. Reichman 96 Management of Specific Soft Tissue Injuries . . . . . . . . . 659 Christopher J. Russo and Ajay Desai
115 Lumbar Puncture . . . . . . . . . . . . . . . . . . . . . . . . . 747 Eric F. Reichman, Kevin Polglaze, and Brian Euerle 116 Burr Holes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 761 Eric F. Reichman 117 Lateral Cervical Puncture . . . . . . . . . . . . . . . . . . . . 767 Eric F. Reichman 118 Ventriculostomy . . . . . . . . . . . . . . . . . . . . . . . . . . 770 Eric F. Reichman 119 Ventricular Shunt Evaluation and Aspiration . . . . . . . . . 775 Eric F. Reichman
97 Subcutaneous Foreign Body Identification and Removal . . . . . . . . . . . . . . . . . . . 669 Samuel J. Gutman and Michael B. Secter
120 Subdural Hematoma Aspiration in the Infant . . . . . . . . 779 Eric F. Reichman
98 Ultrasound-Guided Foreign Body Identification and Removal . . . . . . . . . . . . . . . . . . . 676 Daniel S. Morrison
121 Skeletal Traction (Gardner-Wells Tongs) for Cervical Spine Dislocations and Fractures . . . . . . . . . . 783 Eric F. Reichman
99 Tick Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . 679 Zach Kassutto
122 Edrophonium (Tensilon) Testing . . . . . . . . . . . . . . . . 786 Eric F. Reichman
100 Fishhook Removal . . . . . . . . . . . . . . . . . . . . . . . . 681 Eric F. Reichman and Renee C. Hamilton
SECTION 9 Anesthesia and Analgesia . . . . . . . . . . . . 789
101 Ring Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . 684 Steven H. Bowman
123 Local Anesthesia. . . . . . . . . . . . . . . . . . . . . . . . . . 789 Michael A. Schindlbeck
102 Subungual Hematoma Evacuation . . . . . . . . . . . . . . . 690 Steven H. Bowman
124 Topical Anesthesia . . . . . . . . . . . . . . . . . . . . . . . . 795 Erika D. Schroeder and Peter Taillac
103 Subungual Foreign Body Removal . . . . . . . . . . . . . . . 694 Steven H. Bowman
125 Hematoma Blocks . . . . . . . . . . . . . . . . . . . . . . . . . 799 Thomas P. Graham
104 Nail Bed Repair . . . . . . . . . . . . . . . . . . . . . . . . . . 697 Raemma Paredes Luck and Eric F. Reichman
126 Regional Nerve Blocks (Regional Anesthesia) . . . . . . . . 802 Eric F. Reichman, Jehangir Meer, and Nikesh Seth
105 Ganglion Cyst Aspiration and Injection . . . . . . . . . . . . 704 Thomas P. Graham
127 Intravenous Regional Anesthesia . . . . . . . . . . . . . . . . 843 Christopher Freeman
106 Subcutaneous Abscess Incision and Drainage . . . . . . . . 706 Samuel J. Gutman and Michael B. Secter
128 Nitrous Oxide Anesthesia . . . . . . . . . . . . . . . . . . . . 849 Antonio E. Muñiz
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129 Procedural Sedation and Analgesia (Conscious Sedation) . . . . . . . . . . . . . . . . 854 Hagop M. Afarian
SECTION 10 Obstetrical and Gynecologic Procedures . . . . . . . . . . . . 869
149 Phimosis Reduction . . . . . . . . . . . . . . . . . . . . . . . . 995 Eric F. Reichman and Natana Peres 150 Dorsal Slit of the Foreskin . . . . . . . . . . . . . . . . . . . . 998 Carlos J. Roldan 151 Manual Testicular Detorsion . . . . . . . . . . . . . . . . . . 1001 Steven Go
130 Ultrasound in Pregnancy . . . . . . . . . . . . . . . . . . . . 869 Srikar Adhikari and Wes Zeger
152 Zipper Injury Management . . . . . . . . . . . . . . . . . . 1004 Zach Kassutto
131 Normal Spontaneous Vaginal Delivery . . . . . . . . . . . . 883 Swati Singh and Susan B. Promes
SECTION 12 Ophthalmologic Procedures . . . . . . . . 1007
132 Episiotomy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 896 Francisco Orejuela
153 Eye Examination . . . . . . . . . . . . . . . . . . . . . . . . . . 1007 Shari Schabowski
133 Shoulder Dystocia Management . . . . . . . . . . . . . . . . 904 Eric F. Reichman and Camaran E. Roberts
154 Contact Lens Removal . . . . . . . . . . . . . . . . . . . . . 1022 Dino P. Rumoro
134 Breech Delivery . . . . . . . . . . . . . . . . . . . . . . . . . . 910 Irene E. Aga
155 Ocular Burn Management and Eye Irrigation . . . . . . . 1026 Steven J. Socransky
135 Postpartum Hemorrhage Management . . . . . . . . . . . . 917 Leah W. Antoniewicz
156 Intraocular Pressure Measurement (Tonometry) . . . . . 1032 Michelle M. Verplanck, Mark A. Rolain, and Aaron D. Cohn
136 Perimortem Cesarean Section . . . . . . . . . . . . . . . . . 922 Silvia Linares
157 Digital Globe Massage . . . . . . . . . . . . . . . . . . . . . 1038 Carlos J. Roldan and Eric F. Reichman
137 Symphysiotomy . . . . . . . . . . . . . . . . . . . . . . . . . . 928 Ikem Ajaelo
158 Anterior Chamber Paracentesis. . . . . . . . . . . . . . . . . 1041 Rene Pineda Carizey
138 Bartholin Gland Abscess or Cyst Incision and Drainage . . . . . . . . . . . . . . . . . . . 930 Charlie C. Kilpatrick
159 Corneal Foreign Body Removal. . . . . . . . . . . . . . . . 1043 Eric F. Reichman
139 Sexual Assault Examination . . . . . . . . . . . . . . . . . . . 935 Ann I. Schutt-Ainé and Audra E. Timmins 140 Culdocentesis . . . . . . . . . . . . . . . . . . . . . . . . . . . 945 David L. Levine
160 Corneal Rust Ring Removal . . . . . . . . . . . . . . . . . . . 1047 Eric F. Reichman 161 Eye Patching and Eye Shields . . . . . . . . . . . . . . . . . 1050 Rebecca R. Roberts
141 Prolapsed Uterus Reduction . . . . . . . . . . . . . . . . . . . 948 Eric R. Snoey
162 Lateral Canthotomy and Cantholysis or Acute Orbital Compartment Syndrome Management . . . . . . 1053 Jamil D. Bayram and Sami H. Uwaydat
SECTION 11 Genitourinary Procedures . . . . . . . . . . . 953
163 Globe Luxation Reduction . . . . . . . . . . . . . . . . . . . 1056 Jeffrey S. Schlab
142 Urethral Catheterization . . . . . . . . . . . . . . . . . . . . . 953 Richard Dean Robinson and Eric F. Reichman
164 Hordeolum (Stye) Incision and Drainage . . . . . . . . . . 1058 Sami H. Uwaydat and Jamil D. Bayram
143 Suprapubic Bladder Aspiration . . . . . . . . . . . . . . . . . 963 Richard Dean Robinson, Sam Hsu, and Eric F. Reichman
SECTION 13 Otolaryngologic Procedures . . . . . . . . 1063
144 Suprapubic Bladder Catheterization (Percutaneous Cystostomy) . . . . . . . . . . . . . . . . . . . 968 Richard Dean Robinson, Sam Hsu, and Eric F. Reichman 145 Retrograde Urethrography and Cystography . . . . . . . . 976 Richard Dean Robinson and Eric F. Reichman 146 Anesthesia of the Penis, Testicle, and Epididymis . . . . . . 981 Eric F. Reichman 147 Priapism Management . . . . . . . . . . . . . . . . . . . . . . 984 Steven Go 148 Paraphimosis Reduction . . . . . . . . . . . . . . . . . . . . . 989 Ann P. Nguyen
165 External Auditory Canal Foreign Body Removal . . . . . . 1063 Rebecca R. Roberts 166 Cerumen Impaction Removal . . . . . . . . . . . . . . . . . . 1070 Rebecca R. Roberts 167 Tympanocentesis . . . . . . . . . . . . . . . . . . . . . . . . . 1075 Paul J. Jones 168 Auricular Hematoma Evacuation . . . . . . . . . . . . . . . . 1078 Eric F. Reichman 169 Nasal Foreign Body Removal . . . . . . . . . . . . . . . . . 1084 Raemma Paredes Luck
Contents
170 Nasal Fracture Reduction . . . . . . . . . . . . . . . . . . . 1092 Eric F. Reichman 171 Nasal Septal Hematoma Evacuation . . . . . . . . . . . . . 1099 Michael Friedman, Meghan Wilson, and George Chiampas 172 Epistaxis Management . . . . . . . . . . . . . . . . . . . . . . 1103 Stephen M. Kelanic, David D. Caldarelli, and Eric F. Reichman 173 Laryngoscopy . . . . . . . . . . . . . . . . . . . . . . . . . . . 1113 Steven Charous 174 Airway Foreign Body Removal . . . . . . . . . . . . . . . . . 1120 David L. Walner
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SECTION 15 Podiatric Procedures . . . . . . . . . . . . . 1169 184 Ingrown Toenail Management . . . . . . . . . . . . . . . . . 1169 Jeff Schaider 185 Toe Fracture Management . . . . . . . . . . . . . . . . . . . . 1173 George Chiampas and Steve Zahn 186 Neuroma Management . . . . . . . . . . . . . . . . . . . . . 1177 Eric R. Snoey and Stephen Miller
SECTION 16 Miscellaneous Procedures . . . . . . . . . . 1181
175 Peritonsillar Abscess Incision and Drainage . . . . . . . . . 1125 Eric F. Reichman, Kellie D. Hughes, and Jehangir Meer
187 Relief of Choking and Acute Upper Airway Foreign Body Removal . . . . . . . . . . . . . . . . . . . . . . 1181 Tamara Espinoza, Shekhar Menon, and John Bailitz
SECTION 14 Dental Procedures . . . . . . . . . . . . . . . 1131
188 Induction of Therapeutic Hypothermia . . . . . . . . . . . . 1185 Mark Hansen, Mike Nelson, and John Bailitz
176 Dental Anesthesia and Analgesia. . . . . . . . . . . . . . . . 1131 Eric F. Reichman
189 Hypothermic Patient Management. . . . . . . . . . . . . . . 1191 Gary An and Nabil Issa
177 Dental Abscess Incision and Drainage. . . . . . . . . . . . . 1141 Daniel J. Ross
190 Hyperthermic Patient Management . . . . . . . . . . . . . . 1201 Eileen F. Couture
178 Post-Extraction Pain and Dry Socket (Alveolar Osteitis) Management . . . . . . . . . . . . . . . . 1146 Eric F. Reichman
191 Autotransfusion . . . . . . . . . . . . . . . . . . . . . . . . . 1205 Carlos J. Roldan and Amit Mehta
179 Post-Extraction Bleeding Management . . . . . . . . . . . . 1148 Eric F. Reichman 180 Defective Dental Restoration Management . . . . . . . . . . 1150 Daniel J. Ross 181 Subluxed and Avulsed Tooth Management . . . . . . . . . . 1154 Daniel J. Ross 182 Fractured Tooth Management . . . . . . . . . . . . . . . . . 1161 Daniel J. Ross 183 Temporomandibular Joint Dislocation Reduction . . . . . . 1165 Marilyn M. Hallock
192 Helmet Removal . . . . . . . . . . . . . . . . . . . . . . . . . 1209 Eric F. Reichman 193 Hazmat Patient Management . . . . . . . . . . . . . . . . . . 1215 Atilla B. Üner 194 Physical Restraints . . . . . . . . . . . . . . . . . . . . . . . . 1218 Cheryl Person, Dean Sagun, and Mark Fanning 195 Chemical Restraint . . . . . . . . . . . . . . . . . . . . . . . . 1224 David K. Duong and Hemal Kanzaria Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1231
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Contributors Srikar Adhikari, MD, MS, RDMS [50, 130]
Leah W. Antoniewicz, MD [135]
Associate Professor Department of Emergency Medicine University of Arizona Medical Center Tucson, Arizona
Staff Physician Obstetrics and Gynecologic Associates Clear Lake Regional Medical Center Houston, Texas
Hagop M. Afarian, MD [94, 129]
Bashar M. Attar, MD, PhD, FACP, FACG, AGAF, FASGE [62, 63]
Assistant Clinical Professor of EM UCSF School of Medicine Department of Emergency Medicine UCSF Fresno Fresno, California
Irene E. Aga, MD [134] Assistant Professor Department of Obstetrics Gynecology, and Reproductive Sciences The University of Texas Health Science Center Houston, Texas
Ikem Ajaelo, MD [137] Staff Physician Emergency Medicine Essentia Health-Sandstone Sandstone, Minnesota
Steven E. Aks, DO, FACMT, FACEP [61] Director The Toxikon Consortium and Division of Toxicology Associate Professor of Emergency Medicine, Rush University Department of Emergency Medicine Cook County Hospital Chicago, Illinois
Piotr C. Aljindi, MD [10] Attending Physician Associate Program Director Department of Anesthesiology Cook County Hospital Assistant Professor of Anesthesiology Rush University Medical Center Chicago, Illinois
Gary An, MD [189]
System-wide Chair for Gastroenterology and Hepatology Cook County Health and Hospitals System Chairman, Division of Gastroenterology and Hepatology Director, GI Fellowship Program John H. Stroger Hospital of Cook County Professor of Medicine Rush University Medical Center Chicago, Illinois
John Bailitz, MD, FACEP, RDMS [187, 188] Emergency Medicine Ultrasound Director Department of Emergency Medicine Cook County Hospital Assistant Professor of Emergency Medicine Rush University Medical Center Chicago, Illinois
Kenny Banh, MD [42] Assistant Clinical Professor of Emergency Medicine, UCSF Emergency Medicine University of California San Francisco Fresno Fresno, California
Jamil D. Bayram, MD, MPH, EMDM, MEd [69, 162, 164] Assistant Professor Emergency Medicine Johns Hopkins University Baltimore, Maryland
Daniel Belmont, MD [47, 48] Attending Physician Department of Emergency Medicine Elmhurst Memorial Hospital Elmhurst, Illinois
Joseph Bledsoe, MD [21]
Associate Professor of Surgery Department of Surgery University of Chicago Medicine Chicago, Illinois
Surgery-Adjunct Assistant Professor Emergency Medicine University of Utah School of Medicine Salt Lake City, Utah
Sobia Ansari, MD, MPH [75]
Heather H. Bohn, DO [78]
Instructor Emergency Department Rush University Medical Center Chicago, Illinois
Staff Physician Arrowhead Regional Medical Center Loma Linda University Med Center Colton, California xiii
xiv
Contributors
David W. Boldt, MD, MS [8]
Steven Charous, MD, FACS [173]
Assistant Clinical Professor Anesthesiology and Critical Care Medicine Department of Anesthesiology John H. Stroger Hospital of Cook County, Chicago, Illinois David Geffen School of Medicine University of California Los Angeles Los Angeles, California
Clinical Associate Professor Department of Otolaryngology-Head and Neck Surgery Loyola University Medical Center Maywood, Illinois
George Chiampas, DO, FACEM [86, 171, 185]
Professor Division of Emergency Medicine University of Utah Medical School Salt Lake City, Utah
Assistant Professor Department of Emergency Medicine Feinberg School of Medicine Northwestern University Team Physician Northwestern University Medical Director Bank of America Chicago Marathon Chicago, Illinois
Steven H. Bowman, MD, FACEP [101, 102, 103]
Aaron D. Cohn, MD [156]
Program Director Department of Emergency Medicine Cook County Hospital Assistant Professor of Emergency Medicine Rush University Medical Center Chicago, Illinois
Glaucoma Specialists Riddle Eye Associates Riddle Memorial Hospital Media, Pennsylvania
Philip Bossart, MD [17]
Jim Comes, MD [89]
Staff Physician Department of Emergency Medicine Texas Health Presbyterian Flower Mound, Texas
Program Director Health Sciences Clinical Professor Department of Emergency Medicine UCSF School of Medicine UCSF Fresno Emergency Medicine Program Fresno, California
Michael Bublewicz, MD [84]
Joseph Cornett, MD [11]
Clinical Assistant Professor of Emergency Medicine Department of Emergency Medicine University of Texas Health Science Center Houston, Texas
Staff Physician Emergency Department Baptist Health System San Antonio, Texas
David D. Caldarelli, MD [172]
Eileen F. Couture, DO [190]
Professor and Chairman Emeritus Department of Otolaryngology-Head and Neck Surgery Rush University Medical Center Chicago, Illinois
Attending Physician Department of Emergency Medicine Cook County Hospital Assistant Professor of Emergency Medicine Rush University Medical Center Chicago, Illinois
Aaron Brown, MD [24]
Danielle Campagne, MD, FACEP [113] Assistant Clinical Professor of Emergency Medicine Department of Emergency Medicine UCSF-Fresno Fresno, California
Angelique S. Kelly Campen, MD [82] Clinical Instructor of Emergency Medicine Ronald Reagan UCLA Medical Center UCLA Emergency Medicine Center Los Angeles, California
Rene Pineda Carizey, DO [158] Assistant Professor Department of Emergency Medicine Rush University Medical Center Chicago, Illinois
Cristal R. Cristia, MD [40] Staff Physician Department of Emergency Medicine Beth Israel Deaconess Hospital, Milton Milton, Massachusetts
Elizabeth M. Datner, MD [65] Vice Chair of Clinical Operations Department of Emergency Medicine Hospital of the University of Pennsylvania Philadelphia, Pennsylvania
Ajay Desai, MD [96] Attending Physician Emergency Medicine The Children’s Hospital of Philadelphia Philadelphia, Pennsylvania
Contributors
Shoma Desai, MD [9]
Steven Go, MD [147, 151]
Assistant Professor Emergency Medicine LAC + USC Medical Center Los Angeles, California
Associate Professor of Emergency Medicine Department of Emergency Medicine University of Missouri—Kansas City School of Medicine Kansas City, Missouri
Pratik Doshi, MD [53]
Thomas P. Graham, MD, FACEP [105, 125]
Assistant Professor of Emergency Medicine and Internal Medicine Emergency Medicine and Division of Critical Care Department of Internal Medicine University of Texas Health Science Center Houston, Texas
Professor of Medicine/Emergency Medicine Emergency Medicine Center UCLA School of Medicine Los Angeles, California
David K. Duong, MD, MS [195]
Lisa Freeman Grossheim, MD, FACEP [52, 58, 92]
Assistant Professor Department of Emergency Medicine University of California, San Francisco San Francisco, California
Assistant Professor Department of Emergency Medicine University of Texas Health Science Center at Houston-Medical School Houston, Texas
Tamara Espinoza, MD [187]
David D. Gummin, MD [61]
Assistant Professor of Emergency Medicine The Emory Clinic Atlanta, Georgia
Medical Director Poison Center Children’s Hospital of Wisconsin Professor of Emergency Medicine Section Chief of Medical Toxicology Medical College of Wisconsin Milwaukee, Wisconsin
Brian Euerle, MD, RDMS [4, 33, 77, 115] Associate Professor Department of Emergency Medicine University of Maryland School of Medicine Baltimore, Maryland
Mark Fanning, RN [194] Director of Nursing Department of Emergency Medicine Lyndon Baines Johnson General Hospital Houston, Texas
Maggie Ferng, MD [64, 110] Instructor Department of Emergency Medicine Rush University Medical Center Chicago, Illinois
Samuel J. Gutman, MD CCFP(EM) [97, 106] Clinical Associate Professor Faculty of Medicine, Department of Emergency Medicine University of British Columbia Vancouver, British Columbia
Christopher J. Haines, DO, FAAP, FACEP [26] Drexel University College of Medicine Associate Professor of Pediatrics and Emergency Medicine St. Christopher’s Hospital for Children Director, Department of Emergency Medicine Medical Director, Critical Care Transport Team Philadelphia, Pennsylvania
Zak Foy, MD [57]
Marilyn M. Hallock, MD, MS, FACEP [67, 183]
Emergency Physician Emergency Department Memorial Mission Hospital Asheville, North Carolina
Assistant Professor Emergency Department Rush University Medical Center Chicago, Illinois
Christopher Freeman, MD, FACEP [112, 127]
Renee C. Hamilton, MD [100]
Assistant Professor Emergency Medicine Assistant Medical Director University Emergency Department University of Alabama at Birmingham Birmingham, Alabama
Staff Physician Emergency Department Baptist Health System San Antonio, Texas
Michael Friedman, MD [171] Professor and Chairman, Section of Sleep Surgery Rush University Medical Center Professor and Chairman, Section of Otolaryngology Advocate Illinois Masonic Medical Center Medical Director Chicago ENT an Advanced Center for Specialty Care Chicago, Illinois
Mark Hansen, MD [188] Staff Physician Emergency Department Bon Secours-St. Francis Xavier Hospital Charleston, South Carolina
xv
xvi
Contributors
Jaime Harper, MD [76]
Nabil Issa, MBChB, FRCS, FACS [189]
Emergency Medicine Attending Physician St Vincent Hospital Indianapolis, Indiana
Assistant Professor Department of Surgery Northwestern University Feinberg School of Medicine Chicago, Illinois
Stanley Harper, MD [76] Board Certified Plastic Surgeon St Vincent Hospital Indianapolis, Indiana
Ryan C. Headley, MD [64, 110] General Surgeon Suburban Surgical Associates Berwyn, Illinois Clinical Instructor of Surgery Feinberg School of Medicine Northwestern University Chicago, Illinois
Tarlan Hedayati, MD, FACEP [12] Assistant Professor Assistant Program Director Department of Emergency Medicine Cook County (Stroger) Hospital Chicago, Illinois
H. Gene Hern Jr., MD, MS [27] Associate Clinical Professor, UCSF Residency Director, Emergency Medicine Alameda County-Highland Oakland, California
Theltonia Howard, MD [19] Staff Physician South Fulton Medical Center Wellstar Cobb Hospital Atlanta, Georgia
Sam Hsu, MD, RDMS [4, 65, 143, 144] Assistant Professor Emergency Department University of Maryland School of Medicine Baltimore, Maryland
Kellie D. Hughes, MD [175] Attending Physician Department of Emergency Medicine Anderson Hospital Maryville, Illinois
Sandeep Johar, DO, MS, FACEP [66] Assistant Professor Department of Emergency Medicine Hartford Hospital UCONN School of Medicine Hartford, Connecticut
Paul J. Jones, MD [167] Acting Chairman and Assistant Professor Department of Otolaryngology-Head and Neck Surgery Section Head, Pediatric Otolaryngology Rush University Medical Center Chicago, Illinois
Kimberly T. Joseph, MD, FACS, FCCM [39] Division Chair Trauma ICU and Prevention Department of Trauma John H Stroger Hospital of Cook County Chicago, Illinois
Ramasamy Kalimuthu, MD [76] Director of Microsurgery Services Clinical Professor of Plastic and Hand Surgery Advocate Christ Medical Center Chicago, Illinois
Elisabeth Kang, MD [36] Staff Physician Emergency Department Baptist Health System San Antonio, Texas
Hemal Kanzaria, MD [195] Attending Physician Emergency Medicine Ronald Reagan UCLA Medical Center Los Angeles, California
Zach Kassutto, MD, FAAP [7, 88, 99, 152]
Assistant Professor Department of Emergency Medicine University of Missouri Kansas City Truman Medical Center Kansas City, Missouri
Director Pediatric Emergency Medicine Capital Health, New Jersey Associate Professor Pediatrics and Emergency Medicine Drexel University College of Medicine Philadelphia, Pennsylvania Attending Physician Department of Emergency Medicine St. Christopher’s Hospital for Children Philadelphia, Pennsylvania
Eric Isaacs, MD [1]
Stephen M. Kelanic, MD, FACS [172]
Clinical Professor Department of Emergency Medicine San Francisco General Hospital University of California, San Francisco San Francisco, California
Assistant Professor Department of Otolaryngology and Bronchoesophagology Rush University Medical Center Chicago, Illinois
Pholaphat Charles Inboriboon, MD, MPH, FACEP [13]
Contributors
Charlie C. Kilpatrick, MD [138]
M. Scott Linscott, MD [21]
Vice Chairman Associate Professor Department of Obstetrics and Gynecology Texas Tech University Health Science Center School of Medicine Lubbock, Texas
Surgery-Adjunct Professor Emergency Medicine University of Utah School of Medicine Salt Lake City, Utah
Matt Kleinmaier, MD [74, 85]
Jenny J. Lu, MD, MS [59, 60]
Clinical Instructor Department of Emergency Medicine Northwestern Feinberg School of Medicine Chicago, Illinois
Assistant Professor Department of Emergency Medicine Division of Medical Toxicology Cook County Hospital (Stroger) Chicago, Illinois
Mark P. Kling, MD, FAAEM, CSCS [83, 87]
Raemma Paredes Luck, MD [104, 169]
Attending Physician Department of Emergency Medicine Cook County Hospital Assistant Professor of Emergency Medicine Rush University Medical Center Chicago, Illinois
Assistant Professor Department of Emergency Medicine Temple University School of Medicine Philadelphia, Pennsylvania
Umashankar Lakshmanadoss, MD, CCDS [66] Cardiovascular Fellow Division of Cardiology Guthrie Clinic Sayre, Pennsylvania
Todd M. Larabee, MD [31] Assistant Professor Department of Emergency Medicine University of Colorado School of Medicine Aurora, Colorado
John Larkin, MD [77] Attending Physician Emergency Medicine St. Luke’s Episcopal Hospital System Houston, Texas
David L. Levine, MD, FACEP [140] Medical Director-Adult Emergency Services Cook County Hospital (Stroger) Assistant Professor Emergency Medicine Rush University Medical Center Chicago, Illinois
Michael Lutes, MD [14] Assistant Professor of Emergency Medicine Medical College of Wisconsin Madison Emergency Physicians Madison, Wisconsin
O. John Ma, MD [16, 55] Professor and Chair Department of Emergency Medicine Oregon Health and Science University Portland, Oregon
Sanjeev Malik, MD [74, 85] Assistant Professor CAQ Sports Medicine Assistant Medical Director Department of Emergency Medicine Feinberg School of Medicine Northwestern University Chicago, Illinois
Justin Mazzillo, MD [75] Chief Resident Department of Emergency Medicine University of Texas Health Science Center Houston, Texas
Matthew R. Lewin, MD, PhD, FACEP, FCAS [78]
James J. McCarthy, MD [51]
Director Center for Exploration and Travel Health California Academy of Sciences San Francisco, California
Associate Professor of Emergency Medicine Vice-Chair of Operations Department of Emergency Medicine University of Texas Health Science Center at Houston-Medical School Medical Director of Emergency Services Memorial Hermann Hospital-Texas Medical center Houston, Texas
Silvia Linares, MD [136] Assistant Professor Department of Obstetrics and Gynecology University of Texas Health Science Center at Houston-Medical School Attending Physician Obstetrics and Gynecology Lyndon Baines General Hospital Houston, Texas
Myles C. McClelland, MD, MPH [33] Attending Physician Methodist Hospital-Texas Medical Center Attending Physician Methodist West Houston Hospital Houston, Texas
xvii
xviii
Contributors
Jehangir Meer, MD, RDMS, FACEP, FRCPC [4, 36, 40, 126, 175]
Ned F. Nasr, MD [6, 8, 10, 22]
Director of Emergency Ultrasound Department of Emergency Medicine Saint Agnes Hospital Baltimore, Maryland
Vice Chairman for Academic Affairs and Program Director Chairman, Division of Neuroanesthesiology Department of Anesthesiology and Pain Management John H. Stroger, Jr. Hospital of Cook County Chicago, Illinois
Amit Mehta, MD [191]
Mike Nelson, MD, MS [188]
Resident Department of Emergency Medicine University of Texas at Health Science Center at Houston-Medical School Houston, Texas
Attending Physician Emergency Medicine Medical Toxicology Fellow Cook County Hospital (Stroger) Chicago, Illinois
Shekhar Menon, MD [187]
Attending Physician Emergency Trauma Department Hackensack University Medical Center Hackensack, New Jersey
Staff Physician NorthShore Medical Group Emergency Medicine Evanston, Illinois
Stephen Miller, MD [186] Attending Physician Emergency Medicine Highland Hospital/Alameda County Medical Center Oakland, California
Daniel S. Morrison, MD, RDMS, FACEP [98] Assistant Professor Department of Emergency Medicine University of Medicine and Dentistry of New Jersey-Robert Wood Johnson Medical School New Brunswick, New Jersey
Amanda Munk, MD [16, 55] Staff Physician Emergency Medicine Associates PC Southwest Washington Medical Center Vancouver, Washington
Antonio E. Muñiz, MD [56, 84, 128] Attending Physician Dallas Regional Medical Center Dallas, Texas
Arun Nagdev, MD [49] Director of Emergency Ultrasound Ultrasound Fellowship Director Department of Emergency Medicine Alameda County Medical Center Highland General Hospital Oakland, California
Isam F. Nasr, MD [6, 8, 10, 22] Attending Physician Department of Emergency Medicine Cook County Hospital Assistant Professor of Emergency Medicine Rush University Medical Center Chicago, Illinois
Ann P. Nguyen, MD [148]
Flavia Nobay, MD [54] Program Director Department of Emergency Medicine University of Rochester Rochester, New York
Amy Noland, MD [56] Assistant Professor of Emergency Medicine Department of Emergency Medicine University of Texas Health Science Center at Houston-Medical School Houston, Texas
Nnaemeka G. Okafor, MD, MS [34] Assistant Professor Medical Director of Informatics Department of Emergency Medicine University of Texas Health Science Center at Houston-Medical School Houston, Texas
Francisco Orejuela, MD [132] Associate Professor Department of Obstetrics and Gynecology University of Texas Health Science Center at Houston-Medical School Houston, Texas
Charles Orsay, MD [68, 70, 71, 72] Chair Department of Colorectal Surgery Cook County Hospital Professor of Surgery Rush University Medical Center Chicago, Illinois
Lisa R. Palivos, MD [107, 108] Attending Physician Department of Emergency Medicine Cook County Hospital Assistant Professor of Emergency Medicine Rush University Medical Center Chicago, Illinois
Contributors
Sharad Pandit, MBBS, DABP, FACEP [88]
Simon M. Pulfrey, MSc, MD, CCFP(EM) [32]
Attending Physician Emergency Department Royal Adelaide Hospital Adelaide, Australia
Clinical Assistant Professor Department of Emergency Medicine University of British Columbia Vancouver, British Columbia
Olga Pawelek, MD [14, 15]
Raed Rahman, DO [22]
Assistant Professor Department of Anesthesiology University of Texas Health Science Center at Houston-Medical School Houston, Texas
Medical Director of Pain Management Cancer Treatment Centers of America Midwestern Regional Medical Center Zion, Illinois
Natana Peres, MD [149] Assistant Professor Department of Emergency Medicine University of Texas Health Science Center at Houston-Medical School Houston, Texas
Cheryl Person, MD [194] Assistant Professor of Psychiatry Department of Psychiatry and Behavioral Sciences University of Texas Health Science Center at Houston-Medical School Houston, Texas
Roland Petri, MD, MPH [23] Attending Physician Department of Emergency Medicine Mayo Clinic Arizona Scottsdale, Arizona
Kevin Polglaze, DO [115] Emergency Department Physician Infinity Healthcare Milwaukee, Wisconsin
Candace Powell, MD [93] Attending Physician Emergency Department Methodist Willowbrook Hospital Houston, Texas
Gregory M. Press, MD, RDMS [3, 29] Assistant Professor Director of Emergency Ultrasound Department of Emergency Medicine University of Texas Health Science Center at Houston-Medical School Houston, Texas
Susan B. Promes, MD, FACEP [65, 131] Professor and Vice Chair for Education Department of Emergency Medicine University of California San Francisco San Francisco, California
xix
Amy Rasmussen, MD [29] Staff Physician Emergency Department Doctors Medical Center of Modesto Modesto, California
Eric F. Reichman, PhD, MD, FAAEM, FACEP [11, 15, 24, 25, 33, 36, 38, 40, 41, 43, 44, 45, 46, 56, 67, 68, 69, 70, 71, 72, 75, 77, 80, 81, 83, 90, 91, 93, 95, 100, 104, 112, 115, 116, 117, 118, 119, 120, 121, 122, 126, 133, 142, 143, 144, 145, 146, 149, 157, 159, 160, 168, 170, 172, 175, 176, 178, 179, 192] Associate Professor of Emergency Medicine Attending Physician, Department of Emergency Medicine Medical Director, Surgical and Clinical Skills Center University of Texas Health Science Center at Houston-Medical School Houston-Medical School Attending Physician, Emergency Department Memorial Hermann Hospital-Texas Medical Center Attending Physician, Emergency Department Lyndon Baines Johnson General Hospital Houston, Texas
Camaran E. Roberts, MD [133] Staff Physician Methodist Willowbrook Hospital Houston, Texas
Rebecca R. Roberts, MD [161, 165, 166] Director of Research Department of Emergency Medicine Cook County Health and Hospitals System Assistant Professor Department of Emergency Medicine Rush University Medical Center Chicago, Illinois
Richard Dean Robinson, MD [142, 143, 144, 145] Chairman Department of Emergency Medicine John Peter Smith Health Network Fort Worth, Texas
Leonardo Rodriguez, MD [12] Assistant Professor of Emergency Medicine Keck School of Medicine of USC Emergency Department LAC + USC Medical Center Los Angeles, California
xx
Contributors
Mark A. Rolain, MD [156]
Payman Sattar, MD, MS, FACC [30, 37]
Professor of Ophthalmology Oakland University/William Beaumont Medical School Director of Refractive Surgery and Clinical Instructor Beaumont Eye Institute Royal Oak, Michigan
Attending Physician Department of Cardiology Cook County Hospital Associate Professor of Medicine Rush University Medical Center Chicago, Illinois
Carlos J. Roldan, MD, FACEP, FAAEM [35, 111, 150, 157, 191] Associate Professor of Emergency Medicine Department of Emergency Medicine The University of Texas Health Science Center at Houston-Medical School Houston, Texas
Teresa M. Romano, MD [26] Pediatric Emergency Medicine Physician Emergency Medicine Lehigh Valley Hospital Allentown, Pennsylvania
John S. Rose, MD, FACEP [2] Professor Department of Emergency Medicine University of California Health System Sacramento, California
Daniel J. Ross, MD, DDS, FACEP [177, 180, 181, 182] Attending Physician Section of Emergency Medicine Jesse Brown VA Medical Center Chicago, Illinois Clinical Assistant Professor Department of Emergency Medicine University of Illinois at Chicago Chicago, Illinois
Dino P. Rumoro, DO, FACEP [154] Assistant Professor and Clinical Chairman Department of Emergency Medicine Rush University Medical Center Chicago, Illinois
Christopher J. Russo, MD [7, 96] Attending Physician Division of Emergency Medicine Nemours/A.I. duPont Hospital for Children Wilmington, Delaware
Dean Sagun, BA, EMT-I [194] Medical Student (MS4) Department of Emergency Medicine The University of Texas at Houston Medical School Houston, Texas
Joseph A. Salomone III, MD [28] EMS Medical Director Section Chief and Associate Professor EMS Section Department of Emergency Medicine UMKC School of Medicine/Truman Medical Center Kansas City, Missouri
Shari Schabowski, MD [153] Attending Physician Department of Emergency Medicine Cook County Hospital Assistant Professor of Emergency Medicine Rush University Medical Center Chicago, Illinois
Jeff Schaider, MD [184] Chairman Department of Emergency Medicine Cook County Health and Hospital System Professor Department of Emergency Medicine Rush University Medical Center Chicago, Illinois
Michael A. Schindlbeck, MD, FACEP [114, 123] Assistant Program Director Department of Emergency Medicine Cook County Hospital Assistant Professor of Emergency Medicine Rush University Medical Center Chicago, Illinois
Jeffrey S. Schlab, MD [163] Staff Physician Emergency Department Seton Medical Center Austin, Texas
Erika D. Schroeder MD, MPH [21, 124] Attending Physician Department of Emergency Medicine Providence Regional Medical Center Everett, Washington
Ann I. Schutt-Ainé, MD [139] Assistant Professor of Obstetrics and Gynecology Department of Obstetrics and Gynecology Baylor College of Medicine Houston, Texas
Michael B. Secter, MD [97, 106] Resident Physician Department of Obstetrics and Gynecology University of Toronto Toronto, Canada
Nikesh Seth, MD [126] Valley Pain Consultants St. Joseph’s Hospital and Medical Center-Phoenix Phoenix, Arizona
Contributors
Fred A. Severyn, MD, FACEP [18]
Susan Stroud, MD [57]
Associate Professor Emergency Medicine University of Colorado School of Medicine Aurora, Colorado
Associate Clinical Professor of Surgery Division of Emergency Medicine University of Utah School of Medicine Salt Lake City, Utah
Scott C. Sherman, MD, FAAEM [79]
Peter Taillac, MD [124]
Associate Residency Director Department of Emergency Medicine Cook County Hospital (Stroger) Associate Professor of Emergency Medicine Rush University Medical Center Chicago, Illinois
Clinical Associate Professor Department of Surgery Division of Emergency Medicine University of Utah School of Medicine Salt Lake City, Utah
Swati Singh, MD [131] Clinical Instructor Emergency Medicine UCSF San Francisco, California
Craig Sisson, MD [49] Assistant Professor/Clinical Emergency Medicine The University of Texas Health Science Center at San Antonio San Antonio, Texas
Harold A. Sloas, DO, RDMS [91] Assistant Clinical Professor of Adult and Pediatric Emergency Medicine Department of Emergency Medicine The University of Texas Health Science Center at Houston-Medical School Houston, Texas
Lauren M. Smith, MD [109] Director, Observation Unit Department of Emergency Medicine Cook County Hospital Assistant Professor of Emergency Medicine Rush University Medical Center Chicago, Illinois
Eric R. Snoey, MD [141, 186] Vice Chair Department of Emergency Medicine Alameda County Medical Center, Oakland, California Clinical Professor of Emergency Medicine, UCSF Medical Center San Francisco, California
Steven J. Socransky, MD, FRCPC, DABEM [155] Assistant Professor Northern Ontario School of Medicine Emergency Physician and Trauma Director Health Sciences North Sudbury, Ontario
Elizabeth Sowell, MD [38] Assistant Medical Director Department of Emergency Medicine St. Luke’s Hospital at The Vintage Houston, Texas
Katrin Takenaka, MD, Med [19] Associate Program Director Associate Professor Department of Emergency Medicine The University of Texas at Health Science Center at Houston-Medical School Houston, Texas
Audra E. Timmins, MD, MBA [139] Assistant Professor Medical Director of Women’s Services Texas Children’s Hospital Pavilion for Women Obstetrics and Gynecology Baylor College of Medicine Houston, Texas
Dedra Tolson, MD [73] Staff Physician Department of Emergency Medicine Madigan Army Medical Center Tacoma, Washington
Joseph E. Tonna, MD [78] Emergency Medicine Resident Stanford/Kaiser Emergency Medicine Residency Stanford University Stanford, California
Serge G. Tyler, MD [6] Chairman Department of Anesthesiology and Pain Management Division of Adult Anesthesia John H. Stroger, Jr. Hospital of Cook County Chicago, Illinois
Atilla B. Üner, MD, MPH, FAAEM [193] Associate Clinical Professor of Medicine/Emergency Medicine David Geffen School of Medicine at UCLA Emergency Medicine Center Ronald Reagan UCLA Medical Center Los Angeles, California
Sami H. Uwaydat, MD [162, 164] Assistant Professor Ophthalmology Jones Eye Institute/UAMS Little Rock, Arkansas
xxi
xxii
Contributors
Michelle M. Verplanck, DO [156]
Meghan Wilson, MD [171]
General Ophthalmologist Kensington Ophthalmology Brighton, Michigan
Otolaryngology Resident (PGY4) Department of Otolaryngology Louisiana State University Health Sciences Center New Orleans, Louisiana
Gennadiy Voronov, MD [6] Chairman Department of Anesthesiology and Pain Management John H. Stroger, Jr. Hospital of Cook County Chicago, Illinois
Michael Wallace, MD [17] Emergency Medicine University of Utah Salt Lake City, Utah
David L. Walner, MD [174] Associate Professor Department of Otolaryngology Rush University Medical Center Chicago, Illinois Pediatric Otolaryngology Advocate Children’s Hospital Park Ridge, Illinois
Joseph Weber, MD [20] EMS Medical Director Chicago EMS System Department of Emergency Medicine Cook County Hospital Assistant Professor of Emergency Medicine Rush University Medical Center Chicago, Illinois
Steve Zahn, MD [86, 185] Staff Physician Emergency Department Sherman Health Elgin, Illinois
Wes Zeger, DO [5, 130] Associate Professor Department of Emergency Medicine The Nebraska Medical Center Omaha, Nebraska
Robert M. Zesut, DO, MPH [90] Director of Physician Coding and Compliance Emergency Medicine Medical Center Emergency Physicians / Endeavor Medical Systems Houston, Texas
Preface The scope of Emergency Medicine is extremely broad and covers the neonate through the geriatric, surgical, and medical, and encompasses all organ systems. Emergency Medicine is rapidly evolving to reflect our increasing experience, knowledge, and research. Procedural skills must supplement our cognitive skills. Achieving proficiency in procedural skills is essential for the daily practice of Emergency Medicine. We have produced a clear, complete, and easy-to-understand textbook of Emergency Medicine procedures. This text will provide all practitioners, from the medical student to the seasoned Emergentologist, with a single procedural reference on which to base clinical practices and technical skills. The primary purpose of this text is to provide a detailed and step-by-step approach to procedures performed in the Emergency Department. It is expressly about procedures. While well referenced, it is not meant to be a comprehensive reference but an easy-touse and clinically useful procedure book that should be in every Emergency Department. The contents and information are complete. It is organized and written for ease of access and usability. The detail is sufficient to allow the reader to gain a thorough understanding of each procedure. When available, alternative techniques or hints are presented. Each chapter provides the reader with clear and specific guidelines for performing the procedure. Although some may use this text as a library reference, its real place is in the Emergency Department where the procedures are performed. Despite its size, we hope that this book will find its way to the bedside to be used by medical students, residents, and practicing clinicians. This book will satisfy the needs of physicians with a variety of backgrounds and training. While this text is primarily written for Emergentologists, many other practitioners will find this a valuable reference. This book is written for those who care for people with acute illness or injury. Medical students and residents will find this an authoritative work on procedural skills. Medical students, residents, nurse practitioners, physician’s assistants, and practitioners with limited experiences will find all the information in each chapter to learn the complete procedure. Family Physicians, Internists, and Pediatricians will find this text useful to review procedures infrequently performed in the clinic, office, or urgent care center. Intensivists and Surgeons involved in the care of acutely ill patients will also find this book a wonderful resource. The experienced clinician can get a quick refresher on the procedure while enhancing their knowledge and skills. Physicians actively involved in the education of medical students and residents will find this text an easy-to-understand and well-illustrated source of didactic material. The text has 16 sections containing 195 chapters. The contents are organized into sections, each representing an organ system, an area of the body, or a surgical specialty. Each chapter is devoted to a single procedure. This should allow quick access to complete information. The chapters have a similar format to allow information to be retrieved as quickly and as efficiently as possible. There are often several acceptable methods to perform a procedure. While alternative techniques are described in many chapters, we have not exhaustively included all alternative techniques. Key information, cautions, and important facts are highlighted throughout the text in bold type.
Each chapter, with a few exceptions, has a standard format. The relevant anatomy and pathophysiology are discussed followed by the indications and contraindications for the procedure. A list is provided of the necessary equipment. The patient preparation, including consent, anesthesia, and analgesia, is addressed. The procedure is then described in a step-by-step format. Cautions are placed where problems commonly occur. Alternative techniques and helpful hints for each procedure are presented. The aftercare and follow-up are discussed. Any potential complications are described, including the methods to reduce and care for the complications. Finally, a summary contains a review of any critical or important information. This book covers a wide variety of procedures. We have made an effort to think of most procedures that may be performed in a rural or urban Emergency Department and have incorporated it into this text. This includes procedures performed routinely or rarely. It also includes procedures that are often performed in the acute care, clinic, and office setting. Some of the procedures in this book may be performed frequently in the daily practice of Emergency Medicine, such as laceration repair or endotracheal intubation. Other procedures, such as a cricothyroidotomy, are seldom to rarely performed but critical to the practice of Emergency Medicine. While many of the procedures are well known to the Emergentologist, some are uncommon and may not be known to the reader. This provides an opportunity to acquire new information that may be converted, with proper practice and training, into a useful skill. A few of the procedures are performed only by Surgeons. They are included to promote understanding by those who may later see the patients in the Emergency Department and have to provide emergent care for a complication. This edition has added chapters to cover additional procedures, especially the Respiratory section. A few chapters of seldom used procedures have been eliminated. We have drawn on a wide variety of authors. The majority of authors are residency-trained, board-certified, and practicing Emergentologists. We have the honor of having many contributors from outside the field of Emergency Medicine, who are experts in their own specialty. The authors do have biases because of differences in education, experience, and training. We have tried to base all recommendations on sound clinical and scientific data. However, we have not excluded personal experience or preferences when appropriate. In these cases, the authors also present alternative techniques. Hopefully, this book has grown and changed with this second edition. Suggestions from you, the reader, would be most appreciated. Let us know what additional procedures should be included or excluded in the future. Eric F. Reichman, PhD, MD
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Acknowledgments This has been educational and time-consuming. I must thank my wife Kristi for all of her patience during this endeavor that took thousands of hours and four years. Joey, Phoebe, Jake, and Rocky always kept me entertained, day and night. I would like to acknowledge the support of friends, colleagues, current residents, and former residents in the Departments of Emergency Medicine at The University of Texas at Houston Medical School and Cook County Hospital. They provided friendship and encouragement, and were always there when needed. A special thanks goes to Bob Simon and Jeff Schaider who got me started and set me on this academic path. A special thanks goes to Brent King, MD, Patricia Butler, MD, and Nancy McNiel, PhD, for all their support and encouragement.
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I would also like to acknowledge Marcy, Venettea, Shadi, Jim, Hoan, and especially Yolanda of the SCSC. Their daily support was invaluable. I want to thank all the authors. Many of you are good friends that I cherish and whom gave of themselves and their time. Susan Gilbert is a wonderful medical illustrator and friend. Her input and assistance only added to the illustrations of both editions of this book. Thanks to all those at McGraw-Hill, especially Anne Sydor and Brian Kearns. You kept me on track, and provided assistance when needed and a kick in the butt when needed. Eric F. Reichman, PhD, MD
SECTION
Introductory Chapters
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Informed Consent for Procedures in the Emergency Department Eric Isaacs
This chapter is designed as a practical reference for the Emergency Physician (EP). It focuses on the unique challenges of informed consent in the Emergency Department (ED). It presents a practical guide for the informed consent process, reviews the exceptions, and offers suggestions on difficult scenarios of informed consent in the ED.
INFORMED CONSENT The right of a patient to make decisions about their body, including the refusal of recommended procedures and treatment, is an important concept in medical practice with foundations in law and medical ethics. Informed consent is the process of communication that demonstrates a physician’s respect for a patient’s right to make autonomous decisions about their healthcare. Informed consent is both an ethical practice and a legal requirement for all procedures and treatments.
UNIQUE CHALLENGES OF INFORMED CONSENT IN THE ED Each practice environment presents its own challenges to the process of obtaining informed consent. Physicians frequently fail to fulfill all the requirements of obtaining informed consent.1 The ED presents significant challenges, which, despite assumptions to the contrary, results in a greater need to spend time delivering information and engaging patients in their care decisions to the fullest extent possible (Table 1-1). Time pressure and acuity are the most critical factors that influence the care paradigm in the ED. Care provided in the ED spans the full continuum of care (nonacute care is increasingly sought in the ED) and addresses the full spectrum of society (patients from diverse health literacy, language origins, socioeconomic backgrounds, and other recognized vulnerable populations—elderly, children, prisoners). Emergency Physicians need to be prepared to address the broad clinical needs of diverse patients under pressure without the historical physician–patient relationship. Systemic constraints exacerbate this challenged professional context as patients have no choice in the treating physician or the
TABLE 1-1 Challenges for the Emergency Physician to Spend Time Engaged in Conversation with a Patient Time pressure Little privacy Pace of care challenges lay person decisions No prior relationship Lack of facility choice Public health- or system-imposed constraints
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treating facility, which is often dictated by EMS protocols. Tension may arise when a patient’s wishes conflict with greater societal or institutional needs for efficiency and protocol compliance independent of the patient’s preferences and needs. Examples include a trauma activation or a public health emergency. Increasing space constraints and crowding found in most EDs create a lack of privacy that can impede the free exchange of sensitive information. Procedural interventions in the ED are often concurrently diagnostic and therapeutic, further complicating informed decisions. The torrent of complex medical information physicians provide patients is overwhelming in the most controlled settings, and is only made worse in the high emotion and high stress environment of the ED. Emergency Physicians often make rapid decisions with limited information on a daily basis. Many of our colleagues in other specialties may not share this skill, and our expectations of patients must be equally, if not more, tolerant. The absence of an ongoing physician–patient relationship offers no basis on which to build trust, elicit values, and draw preference knowledge. Lack of a prior relationship tests the EP’s ability to establish an immediate rapport with the patient, and renders the patients’ ability to express their values most important. When there is uncertainty about a patient’s preferences or a potential refusal, there may not be time to ponder the intricacies of medical ethics in the ED or to satisfy all the requirements of searching for the best surrogate decision maker. Many EPs will default to doing as much as possible in these difficult situations,2 but there is often enough time to make a considered decision before acting in the most aggressive fashion. While some say that it is easier to withdraw care once the clinical picture becomes clearer, this aggressive course of action must be balanced with the knowledge that EPs may be performing a painful or unwanted procedure on a patient who has previously made their wishes clear. Traditionally, informed consent was often bypassed under the presumption that a patient would want aggressive treatment. The scope of ED care and societal norms have shifted in recent years. Informed consent for procedures in the ED needs to reflect the current standards of practice.
LEGAL FOUNDATION FOR INFORMED CONSENT Consent originates in the legal doctrine of battery (touching of the body without permission). The notion of protecting a patient from the bodily trespass of a procedural invasion was framed by Justice Cardozo in 1914, “[e]very human being of adult years and sound mind has a right to determine what shall be done with his own body; and a surgeon who performs an operation without his patient’s consent commits an assault, for which he is liable in damages … .”3 By 1957, the notion of consent shifted from mere permission to an authorization following “the full disclosure of facts necessary to an informed consent.”4 Emerging at the same time as the bioethics movement’s shift away from paternalistic medicine toward a patient’s rights focus in medicine was Canterbury v Spence.5 This case resulted in an appeals court establishing a physician’s duty to disclose the risks and benefits of a procedure and its alternatives and introduced the reasonable patient standard. The reasonable patient standard is what a reasonable patient would 1
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need to know to make an informed choice shifting away from the professional standard, what most physicians deemed necessary. Today, the standard for disclosure varies by state.6 As a result of the informed consent “duty,” the legal and risk management function of informed consent (consent process that meets institutional and/or legal parameters for formal recognition referred to as ‘effective consent’) overshadows the ethically driven process of informed consent (consent as communication process that demonstrates respect for a patient’s autonomy referred to as ‘autonomous authorization’). Often conflated under the “informed consent,” these two aspects serve distinct functions. Both are necessary for valid informed consent and are addressed separately throughout this chapter.7
LEGAL FOUNDATION OF THE EMERGENCY EXCEPTION The exception presuming permission to treat in an emergency has equally deep roots. Justice Cardozo’s opinion continues, “[t]his is true except in cases of emergency where the patient is unconscious and where it is necessary to operate before consent can be obtained.”3 In Canterbury v Spence, “the emergency exception” is included as a privilege from the duty to disclose when “the patient is unconscious or otherwise incapable of consenting, and harm from a failure to treat is imminent and outweighs any harm threatened by the proposed treatments.” It also states that a “physician should, as current law dictates, attempt to secure a relative’s consent if possible.” In the emergency context one may presume permission: (1) to do what is necessary when (a) there is imminent harm from nontreatment and (b) harm from nontreatment outweighs the harm from the proposed intervention; (2) where the patient is unconscious or unable to participate in care decisions; and (3) the patient’s preferences are not known and no surrogate is immediately available to provide authorization.8
ETHICAL FOUNDATION FOR INFORMED CONSENT In an era of patients’ rights and shared decision making, robust informed consent reflects a process of communication that secures that a patient “gives an informed consent to an intervention if (and perhaps only if) one is competent to act, receives a thorough disclosure, comprehends the disclosure, acts voluntarily, and consents to the intervention.”9 It is not uncommon to encounter the challenge of a patient refusing a recommended procedure or intervention in a healthcare environment where there is an expectation for more active patient participation in healthcare decisions. Central to a strong patient– physician relationship is the desire to promote patient well-being and simultaneously respect patient autonomy. Conflict between EPs and patients may arise when views of what is in a patient’s best interest differ. Emergency Physicians with the greatest integrity come to work with the intention to act in the best interests of patients, and do so with a focus on the prevention and eradication of disease in order to preserve life and improve disability. After an EP has fully informed a capable patient about an intervention in an understandable way, the patient may consent or refuse the recommendation. An initial refusal of recommended treatment should begin a critical conversation that confirms all the elements of an informed refusal. Ultimately, this informed refusal process will respect patient autonomy by accepting a patient’s view of well-being and may require honoring a refusal of the EP’s recommendation.10
EMERGENCY PHYSICIAN’S ROLE AND GOALS IN INFORMED CONSENT PROCESS The EP’s role in the informed consent process is to provide patients the information needed to make their own decisions. It is important
TABLE 1-2 The Goals of Emergency Physicians in the Informed Consent Process Support patients to make their own decision Give information (more than we think we need to give) Make information accessible Offer guidance in weighing information Allow autonomous authorization (patient may consent or refuse)
not to overwhelm a patient with too much information or complex clinical decisions. Including patients in appropriate care decisions, such as the informed consent process for a procedural intervention, is an ethically important goal. Emergency Physicians must pay particular attention to the informed consent process to accomplish the goal of respect for autonomy (Table 1-2). Foremost, EPs need to provide more information to the patient than they think is needed. Research indicates that patients need more information than physicians think they need in order to feel “informed” in the decision-making process.11 The need for a procedure seems obvious to the EP and the balance of the considerations clearly tips in the favor of “do it.” Emergency Physicians must slow down to fully explain the rationale for their recommendation with the patient and to offer the patient information that allows their meaningful consideration of the recommendation allowing them to reach their own decisions. A good guideline is to offer more time and information for procedures carrying greater risk.12 Emergency Physicians must make an effort to work against the features of the ED (Table 1-1 and presumption of consent) and allow patients who are capable of engaging in their care decisions to express autonomous authorization. This is achieved by giving patients sufficient information, in an understandable way, and by honoring their decisions.
COMPONENTS OF THE INFORMED CONSENT AND INFORMED REFUSAL PROCESS Informed consent is the communication process that both demonstrates and protects a patient’s self-determination by providing a patient with decision-making capacity with sufficient, understandable information and allowing the patient to make a voluntary, knowledgeable decision. There are five requirements that must be satisfied.13 These include the patient having decision-making capacity, the EP providing sufficient information, the patient understanding the information, the patient giving consent in a voluntary fashion without coercion, and the patient communicating their decision (Table 1-3).
DECISION-MAKING CAPACITY While the terms “competence” and “decision-making capacity” are frequently used interchangeably, their strict meanings are different.
TABLE 1-3 Requirements of the Informed Consent Process13 1 Does the patient have the decision-making capacity to make this decision? 2 Has there been disclosure of relevant procedural information (including risks/benefits for intervention, alternatives, and nonintervention)? 3 Has the information been presented in a way that is understandable to the patient? 4 Has the information been presented in a way that allows the patient to make his or her own decision voluntarily while still being informed of the physician’s recommendation? 5 Has the patient communicated a decision? 6 Does an exception apply?
CHAPTER 1: Informed Consent for Procedures in the Emergency Department
Competence is a legal term with broader applications related to financial matters and the determination of personal choices. Decision-making capacity is a clinical term that speaks to the specific capacity to make a particular clinical decision. Many people who are legally “incompetent” retain healthcare decision-making capacity. If the patient does not have decision-making capacity, informed consent cannot be obtained and it must be obtained from a surrogate decision maker, or the patient may fall into an exception from informed consent.
DETERMINING DECISION-MAKING CAPACITY The determination that a patient has decision-making capacity is at the core of informed consent. By default, EPs assume that a patient has capacity and confirm this through routine dialogue with the individual. There are six elements that should be confirmed when there is a question about a patient’s capacity to make an informed decision about procedures or treatment.14 The patient must be able to: understand and process the options, weigh the benefits and risks, apply a set of values and goals to the decision, arrive at a decision, communicate a choice, and demonstrate capacity to make the decision (Table 1-4). Determination of capacity is a clinical decision based on the judgment of the EP regarding the patient’s actual level of functioning and appreciation of the ramifications of the clinical situation. The degree of capacity needed to understand risks and benefits of suturing a finger laceration differs from a cardiac catheterization. As such, a patient may be able to understand one choice, but not another. An Alzheimer patient (who is pleasant, oriented to place and year) may be unable to appreciate the consequences of a decision. While this patient may have capacity for some tasks, they may lack the capacity to consent for a specific procedure such as a lumbar puncture. The EP needs to assess the ability for the individual to weigh the risks in light of their own values. An example would be the ramifications of a fracture reduction on the dominant hand. A construction worker or musician may make a decision different than an individual whose livelihood does not depend on perfect hand function. A recognized element of decision-making capacity is whether the patient’s decision is consistent over time. This is not necessarily applicable specifically to the ED. A possible heuristic is whether the decision is consistent with the person’s narrative and values as expressed consistently over time in life choices. The decisionspecific nature of capacity acknowledges that the level of capacity needed depends on the complexity of the decision, with greater capacity needed for decisions with graver consequences. The degree of capacity needed to consent does not necessary equal the degree of capacity needed to refuse a recommended intervention.10 Informed refusal will be discussed later in this chapter. Decision-making capacity is a dynamic process and changes depending on the patient’s evolving condition and task in question. The ED patient may be able to participate to a greater or lesser extent depending on fluctuations in their condition and alterations of their sensorium from the administration of medications. TABLE 1-4 Elements to Determine if a Patient has Decision-Making Capacity 1 The patient is able to understand and process the options presented 2 The patient is able to weigh the relative benefits, burdens, and risks of the options 3 The patient is able to apply a set of values and goals to the decision 4 The patient is able to arrive at a decision that is consistent over time 5 The patient is able to communicate a choice 6 The patient demonstrates capacity appropriate and sufficient to make this decision
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Efforts should be made whenever possible to enhance the patient’s decision-making capacity (reduce pain medication temporarily or visit patients at optimal times) in order to engage them to the fullest extent possible in their care. Emancipated minor and adolescent laws vary from state to state.9 It is important to note that emancipated minors are legally recognized as adults and responsible for their own finances and care. They are able to provide fully informed consent. It is important for EPs to know their local laws where minors who are not emancipated may give consent for sensitive conditions or procedures such as those of a reproductive nature or substance abuse. Informed consent may not be possible with some populations, such as young children and elderly with dementia. It is still possible to inform these patients of the procedure and to engage their assent. Unlike consent, assent is not determinative. It does offer the possibility of the individual participating in their care.15
PATIENTS LACKING DECISION-MAKING CAPACITY It is not possible to obtain informed consent when a patient lacks decision-making capacity. Necessary treatment may be provided to patients who lack decision-making capacity without obtaining the patient’s informed consent. However, EPs should make every effort to learn the patient’s previously stated preferences for treatment (e.g., written advance directive or communication with a primary care provider). Efforts should be made to obtain consent from a surrogate decision maker if prior preferences are not available. A surrogate decision maker is a person entrusted with making healthcare decisions because they know the patient best and can bring the patient’s values and goals into the clinical decision process. This role can be challenging for even the most capable decision makers. It is not uncommon for surrogates to have a role conflict between applying their own values and/or wishes and those of the patient. Emergency Physicians must pay attention to the language used when asking a surrogate decision maker for consent. Frame the discussion with phrases asking what the patient would want in the situation such as “How would your father view this situation?” or “What would your father’s preference be based on his values?” Avoid general phrases such as “What should we do?”, “What do you want us to do?”, or “What do you think he would want?” If the decision seems to stem from a role conflict, an EP can ask the surrogate “Why do you think he would choose that?” No prior conversation covers every clinical scenario perfectly and the gravity of the decision can frequently be overwhelming for the surrogate.10 The choice of a surrogate decision maker may be quite obvious in some cases such as the parent or legal guardian of a child. The choice can be more complex in other cases. Who may serve as a surrogate and their scope of authority varies by state. What if the appropriate surrogate is in question and there is no statutory guidance? A useful guide is that the surrogate’s authority arises from a close relationship to the patient that affords accurate and informed communication of the patient’s values. Challenges in resolving conflict between potential surrogates (e.g., siblings with different opinions regarding parental care) should be referred to an ethics committee or other institutional mechanisms to offer guidance unless emergent conditions make that impractical.
INFORMATION TRANSMITTAL The EP must relate sufficient information about the procedure to the patient. This raises the questions of what information to present and how much to present. Relevant information includes the risks and benefits of the procedure, any alternatives to the proposed course of action, and the consequences of nonaction. The question remains how much information needs to be disclosed to
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patients, particularly in light of the potential that legal action may be taken if an EP does not obtain informed consent properly.16 There are two standards that are commonly used, and these standards vary by state. The traditional “professional standard” requires the EP to provide information based on what the profession’s standard of practice would deem necessary to disclose for a patient to be informed. The more common “reasonable person standard” requires the EP to include all the information that a reasonable patient would want to know in order to make a knowledgeable decision. Information that should be communicated includes: the patient’s current medical condition and how will it progress if no treatment is given, the treatment alternatives, the risks and benefits of each potential treatment and their probabilities, and the financial costs of each if those estimates exist. Finally, the EP should provide a personal recommendation as to the best alternative.17
UNDERSTANDABLE PRESENTATION OF INFORMATION Information must be given in a way that is understandable. The patient must be able to adequately weigh the benefits, burdens, and risks of the treatment in the context of their own beliefs, life, values, and goals. The obvious differential in knowledge and understanding between patients and EPs may be exacerbated by language barriers, literacy, numeracy, and low educational levels.18 Such barriers may be overcome by: speaking at a level easy for the patient to comprehend, being sensitive to patients who may be unable to read, and being sensitive of patients who may not be highly educated. Understanding is bidirectional and necessitates that EPs confirm that the patient understands what they are told.19 Communicating numbers, such as risk and probabilities, is the most complex task asked of EPs.20 Frame numbers in multiple ways and present outcomes in both positive and negative contexts to enhance informed consent.20 For example, “3 out of 4 children have no side effect but one in four will have nightmares from this medication.” Language barriers are frequent in the ED and pose significant concern in obtaining and documenting informed consent.21 Understanding languages is situational. Although some EPs may have additional language (non-English) proficiency, it is imperative to know when to call an interpreter. Limited language skills allow the EP to extract critical clinical information. Patients may need more information than the EP’s skills allow. Calling an interpreter may be essential for meeting a minimum standard of care.22
VOLUNTARY NATURE OF THE DECISION Forced treatment where any real choice is removed from the patient being involved in the decision-making process violates the doctrine of informed consent. Any form of coercion based on threats or intolerable consequences, such as the withholding of pain medication, would fall into this category. Emergency Physicians cannot manipulate patient decisions by withholding or distorting information that the EP believes may sway the patient toward a preferred course. Persuasion is permissible, and it is an obligation as trained professionals to synthesize the information and recommend a course of action. An appropriate recommendation includes laying out the risks, benefits, and reasoning behind one’s recommendation as well as explaining the reasoning for not selecting an alternate approach. Emergency Physicians can also utilize the resources of the patient’s family or significant others to provide arguments in favor of a particular course of treatment. The EP must be careful to avoid overwhelming the patient as the goal should be a shared solution by consensus and not forcing the patient to surrender to the wants of others.23 Strategies to approach a patient’s refusal are discussed in depth later in this chapter.
EFFECTIVE INFORMED CONSENT AND REFUSAL There is a difference between the autonomous authorization informed consent (information and dialogue) and the effective informed consent (to meet legal and institutional requirements). The EP should document the discussion of the benefits, burdens, risks, and alternatives addressed in the discussion with the patient in order for an autonomous authorization to be recognized as effective and, thus, the entire informed consent valid. Local institutional policies should be referenced to confirm an effective informed consent or refusal.7 Some hospitals have patients sign “blanket” consent forms agreeing to all emergency tests and treatments on their registration in the ED. Such consent forms provide no information regarding specific individual procedures. These forms are not acceptable because they fail to respect patient autonomy. Blanket consent forms cannot substitute for the usual informed consent process for procedures in the ED, where a dialogue with the patient is required.24
EXCEPTIONS TO THE INFORMED CONSENT PROCESS THE EMERGENCY EXCEPTION Society’s overriding assumption is that a person would want lifesaving treatment in an emergency situation. Consent to treatment is generally presumed under specific emergency circumstances where intervention is necessary to save life or limb, the harm of nontreatment is greater than the harm of the intervention, a patient is unable to participate in care decisions, and patient preferences are not known with no surrogate available. This emergency exception is not absolute. This is particularly true when there is clear evidence that the patient’s wishes are contrary to the intervention being considered, such as a prehospital advance directive or wallet card stating no blood transfusions. Some EPs believe that any patient in the ED qualifies for an emergency exception by virtue of the fact that they are in the ED. This is not true. Location by itself can be used neither to justify the emergency exception nor to infer an “implied consent” for broad ED care. Rather, the emergency exception may be invoked only when the patient will be harmed by the delay necessary to obtain informed consent.25 EPs should ask themselves a few brief questions to determine if a patient meets the criteria for an emergency exception to informed consent (Table 1-5).
THERAPEUTIC PRIVILEGE The therapeutic privilege is a disfavored concept but recognized exception. It excuses EPs from the duty to disclose in the limited circumstances where disclosure might create harm to the patient and interrupt the treatment process. This privilege is rarely invoked as it could almost negate the entire informed consent process.
TABLE 1-5 Questions to Justify an Emergency Exception 1 Will failure to treat quickly result in serious harm to the patient? 2 If their condition worsens, will the patient die or suffer serious harm before definitive care can be delivered? 3 Would most capable and reasonable people want treatment for this type of injury? 4 Is the patient unable to participate in care decisions? 5 Are the patient’s preferences known or knowable in a timely way from a surrogate? 6 Is there any evidence that the patient would refuse this specific treatment? 7 Would failure to treat result in greater harm than the proposed intervention?
CHAPTER 1: Informed Consent for Procedures in the Emergency Department
Therapeutic privilege may be applied when direct disclosure to a patient would create harm, generally recognized as occurring in some psychiatric conditions and for some cultural groups.26
WAIVER OF INFORMED CONSENT While EPs have a duty to disclose information, patients may differ in how they approach their participation in care decisions. Some patients may prefer that another person, such as a close family member, receive healthcare information and make treatment decisions on their behalf (delegated autonomy). This may be due to personal preference or cultural variation. The delegation of the decision making must be confirmed with the patient and not assumed based on cultural norms. The delegation reflects a patient’s right to waive informed consent. Their choice to delegate that right to another person demonstrates an autonomous choice that should be honored.27 Some patients may interrupt the informed consent process after only partial information is disclosed and elect to follow the EP’s recommendation. If the EP confirms the patient’s acceptance of the consequences of consent with only partial information, the EP may accept this as consent via waiver of the informed consent process.25 The EP may accept a waiver of consent if, like other decisions, the patient has capacity, understands that they are giving up an important right, and has made the request voluntarily. Emergency Physicians who are uncomfortable with this responsibility may ask the patient to designate another person to assume this role.
IMPLIED CONSENT Implied consent is also a disfavored concept. It may be considered to “apply” in the very limited circumstances when an EP is undertaking a clinical activity with a well-known risk/benefit profile.28 The most favored implied consent example is when a patient extends his or her arm for a blood draw. The volitional act of extending the arm is deemed as implied consent to the blood draw and its risks (pain and possible bruising). The assumption of “implied consent” poses a dangerous trap for EPs, since what an EP considers routine and well-known risks may differ greatly from what the patient knows. This is particularly true in the ED where there is little trust and no knowledge of the patient’s health literacy. Emergency Medicine research shows at least 50% of patients wanted time spent on “detailed” information, including a review of the risks of only 1% chance of occurrence. For example, while lumbar punctures are clinically safe and pose little risk, patients perceive this as an invasive procedure that requires more information for informed consent.11 It is important to note that implied consent is not sufficient when informed consent is required or possible.10
UNREPRESENTED PATIENTS/PATIENT ALONE A patient who is unable to participate in care decisions and has no surrogate decision makers is known as the “unrepresented patient” or the “patient alone.” These highly vulnerable patients have no social networks to assist the care team in navigating consent and care decisions, and attention to clinical decision making for this patient population is growing.29 Statutory guidance on decision making for this patient population varies by region. Institutional policies should be reviewed to determine whether a policy exists for decision making for the “unrepresented patient.” In the absence of such a policy, consultation with the ethics service is recommended and efforts should be made to develop a consistent and transparent approach to care decisions for this vulnerable population.27
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INFORMED REFUSAL Emergency Physicians often begin with the presumption that patients possess decision-making capacity to both consent and refuse procedures. It is notable that in practice, EPs may question a patient’s capacity more readily when they disagree with recommendations.
UNDERSTAND THE REASONS FOR REFUSAL A refusal for recommended intervention should be the beginning of an important conversation with the patient. On first encounter, a refusal of a recommendation may seem a rebuff or potential time challenge. Approach a refusal with openness and curiosity. Help the patient not feel cornered into following the recommendation while confirming their informed refusal. A refusal is an opportunity to learn how to practice persuasive reasoning. During the barrage of information disclosure, a patient might have misheard numbers or the proposed procedure may resemble a prior negative experience. Take time to listen to the patient’s concerns and reasons for refusal. This can help navigate the informed refusal process.
CONFIRM THE ADEQUACY OF INFORMATION WITH AN EMPHASIS ON UNDERSTANDABILITY With the patient’s reasons for refusal in mind, EPs should reflect these reasons back to the patient so that they feel they have been heard. It is important for EPs to acknowledge the patient’s perspective, even if they disagree with the reasons. This allows the patient to engage in listening as the EP provides additional information to support the recommendation. Normalizing an “irrational concern” allows the patient to feel “OK” and still follow the EP’s recommendation. For example, “I can understand that your sister’s complication from procedural sedation several years ago would give you some concerns about this recommendation. And I want to reassure you that today we take these additional steps.…” Tailor the revised recommendation to address the concerns of the patient and focus on making sure that the information provided is simple, direct, and understandable.
ADDRESS BARRIERS TO UNDERSTANDING Significant efforts should be undertaken to enhance the patient’s ability to understand the information when a refusal occurs. A professional interpreter must be utilized to compensate for any communication barriers to the patient’s understanding in an informed refusal process. The EP should revisit all the information from the initial discussion of information that occurred with an informal interpreter (e.g., family member or healthcare provider). Residual misinformation can prolong a patient’s refusal. Starting from the beginning of the clinical communication, even if it takes more time, can often remedy the situation. Use language or pictures tailored to a patient’s lower educational or functional level when necessary.19 Anxiety and pain may contribute as a barrier to understanding and should be addressed as quickly as possible.
CONFIRM CAPACITY TO REFUSE RECOMMENDATIONS Is decision-making capacity a potential issue? The EP must take steps to mitigate any factors leading to impaired decision making so that the patient may participate in their care to the fullest extent possible. In the past, it was thought that patients with certain diagnoses by default lacked decision-making capacity. Many clinicians now recognize that patients with severe mental illness, early dementia,
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TABLE 1-6 Red Flag Scenarios that Require Additional Assessments of the Patient’s Decision-Making Capacity Refusal of recommended treatment Patients readily consenting to invasive or risky treatment Abrupt change in mental status Chronic psychiatric or neurologic conditions Cultural and language barriers Limited education Anxiety or untreated pain Extremes of age
and some organic brain syndromes are at risk for impaired decision making but may possess decision-making capacity for selected procedures and treatments.14 However, there are certain Red Flag scenarios when an EP should scrutinize a patient’s decision-making capacity with greater depth (Table 1-6). Actions or decisions with greater consequences require a more intense evaluation of the patient’s capacity. A more careful evaluation of capacity is indicated when the patient’s choice seems unreasonable or if the patient is unwilling to discuss their thought process. Chronic psychiatric and neurologic conditions remain a risk for, but should not be equated with, impaired decision making. Cultural, educational, and language barriers certainly impact a patients’ decision making. High levels of anxiety, whether from untreated pain or the inevitable stress of the ED, are known to impair decision making as well.30 Many providers outside the ED setting will utilize psychiatric consultations to assist with the evaluation of a patient’s decisionmaking capacity. The utility of such a consultation in the ED is frequently limited by time and consultant availability. Consultations in the ED may prove useful when evaluating a thought or delusional disorder that may impede understanding.
EFFECTIVE AUTHORIZATION: DOCUMENTATION OF INFORMED REFUSAL Honoring a refusal of emergency treatment that would be beneficial or may result in decompensation or death is never easy. Use of the standard hospital “Against Medical Advice” form can create an adversarial relationship that an EP may find damaging to future patient interactions and the subsequent treatment plan. However, anecdotal reports include cases where patients reconsidered their decision when presented with such a document. It is important to document refusal of care, not only for medicolegal protection but also to confirm that clear communication with the patient had occurred. Documentation recommendations when a patient refuses treatment should include the following elements: the patient has refused the recommended procedure, test, or treatment; the patient’s reasons for refusal; the consequences of the refusal were explained to the patient including the alternatives, if any, being offered or performed in lieu of the recommended procedure. Documentation should also include statements that show the patient understood and continued to refuse the specific procedure or treatment and has the capacity to do so. Document that the patient’s wishes are being honored against medical advice. It would be preferable if the EP could have the patient read this documentation followed by the patient signing the medical record below this documentation in acknowledgment. Additional documentation is required when an EP recognizes a “Red Flag” scenario for impaired decision making or has other reasons for concern (Table 1-7). These are essential items that must be documented in these cases. Document the patient’s medical condition and the procedure or treatment that is suggested, including
TABLE 1-7 Mnemonic for Documentation of Decision-Making Capacity Assessments “U and I GLAD” U—understanding of the procedure/discussion I—impairing conditions G—goals and values L—logic used to decide A—actual functioning D—danger or risks of decision
the urgency and necessity. Document the patient’s current decisionmaking abilities with a description of the impediments to capacity and the actions taken by the provider to maximize capacity. Additional documentation should include the availability of family or other surrogate decision makers and any relevant discussions. Documentation will vary by institution and local laws. Being familiar with the appropriate measures to make an informed consent or refusal is effective and is a critical part of the informed consent/ refusal process in the ED.31
2
Aseptic Technique John S. Rose
INTRODUCTION The proper use and an understanding of aseptic technique are critical for the care of patients in the Emergency Department (ED). Aseptic technique dovetails with prescribed universal precautions and is central to our practice. Knowledge of proper aseptic technique ensures that procedures performed in the ED provide maximal protection for both the patient and the physician while keeping the risk of contamination as low as possible.1–15 Wound infection and sepsis are the two major complications resulting from poor and improper aseptic technique. Other complications that may contribute to the patient’s morbidity and mortality include increased length and cost of hospital stay, patient discomfort, scarring, and even death. With this is mind, it is clear that aseptic technique is warranted except in the most dire circumstances. Numerous terms are used to describe the establishment and maintenance of a “sterile” environment. These include aseptic, sterile technique, and disinfection, to name a few. Many people often, and incorrectly, interchange these terms. The proper definitions of the terms used to describe aseptic technique or associated with it can be found in Table 2-1.
ANATOMY AND PATHOPHYSIOLOGY The skin and hair are colonized with various organisms. The stratum corneum layer of the epidermis is colonized with a polymicrobial flora. This includes Staphylococcus aureus, Staphylococcus epidermidis, various Streptococcus species, viruses, yeasts, and molds. Many of these organisms are nonpathogenic, even when placed in environments considered appropriate for infection. S. aureus is the most common cause of wound infections. It can result in an infection when introduced into deeper skin layers. Some species, such as S. epidermidis, are pathologic only when inoculated into deeper layers of the skin and soft tissue. For most infections, a significant
CHAPTER 2: Aseptic Technique TABLE 2-1 Definitions of Terms Used to Describe Aseptic Technique or Associated Processes Term Definition Aseptic Freedom from infection. Prevention of contact with microorganisms. Involves the use of sterile technique and skin disinfection Clean technique The practice of using nonsterile equipment to perform procedures. This is considered as part of the universal body fluid precautions Disinfection The cleaning of an area to make it free of pathogenic organisms and microbes Sterile field The zone in which strict sterile technique is maintained. Generally consists of an area 3 to 10 times larger than the area of the primary procedure Sterile technique The practice of utilizing sterile equipment and procedures to maintain an aseptic environment Super aseptic Ultrahigh state of an aseptic environment. Usually, this is achievable only in the operating room
inoculation is required to create a critical level for microbial growth to occur. Aseptic technique decreases bacterial exposure and reduces the level of potentially pathologic organisms.
• • • • • • •
7
Sterile 4 × 4 gauze squares or applicator sticks Sterile gloves Face mask and eye protection Sterile drapes or towels Adequate lighting Sterile gowns Bedside procedure table
PATIENT PREPARATION Inform the patient of what the procedure entails before performing any procedure in the ED. This should include an explanation of sterile technique and a request that the patient not touch the drapes or sterile equipment. Obtain any required informed consent (Chapter 1) before the patient is draped. The only exception to this is if an emergent and lifesaving procedure must be immediately performed. Place the patient in the most comfortable position possible. Patient discomfort frequently results in movement and the potential loss of the sterile field. Utilize sedation and/or analgesia (Chapters 123-129) as necessary to facilitate proper patient positioning. The physician must also be comfortably positioned if possible and have adequate lighting.
INDICATIONS The role of aseptic technique in the ED is primarily for invasive procedures. Despite this, invasive procedures require varying degrees of aseptic technique. Placement of a small peripheral intravenous catheter may require no more than a brief wiping of the skin. In contrast, a diagnostic peritoneal lavage requires operating room–level disinfection and strict sterile technique. Routine and adequate provider disinfection involves careful hand washing, the use of clean and disinfected personal diagnostic equipment (e.g., stethoscopes), and wearing appropriately cleaned coats and clothing. This is critical in preventing iatrogenic infections in the ED. Aseptic technique in the ED can be referred to as clinical aseptic technique, since it is virtually impossible to achieve an operating room level of asepsis. Clinical aseptic technique involves the combining of adequate disinfection with sterile techniques and protocols at the bedside.
CONTRAINDICATIONS There are very few contraindications to the maintenance of adequate clinical aseptic technique. One exception would be that extreme clinical circumstance in which time simply does not allow proper aseptic technique, as in an emergent thoracotomy. Even in such situations, however, the physician can still use sterile gloves and a quick application of an aseptic solution. Always inquire about allergies and sensitivities to latex and antiseptic solutions. This information will affect the equipment that is chosen to properly prepare the patient.8 Most, if not all, hospitals have a latex-free cart that contains equipment for use with latexallergic patients. Do not use povidone iodine solution in patients allergic to iodine. Alternative agents include chlorhexidine and hexachlorophene preparations.
EQUIPMENT • Povidone iodine solution • Chlorhexidine gluconate (chlorhexidine)– or hexachlorophenebased solutions • Seventy percent isopropyl alcohol
TECHNIQUES Aseptic technique can be divided into skin disinfection and sterile technique. Skin disinfection removes any microorganisms found on the skin and decreases potential contamination during the procedure. Sterile technique is performed for the same reason. There are different levels of aseptic technique, ranging from full aseptic technique (mask, gown, gloves, and drapes) to simple sterile gloves. The physician must use their judgment to determine which level is most appropriate to the task at hand.8
SKIN DISINFECTION Disinfection involves the application and scrubbing of a disinfectant preparation onto the skin. Simple procedures, such as injections or venipunctures, may require little disinfection. Wipe the skin with gauze that has been impregnated with 70% isopropyl alcohol for simple procedures. The alcohol has an antibacterial effect. The mere force of wiping the skin reduces bacterial counts. No disinfection is used for simple venipunctures in some countries. More comprehensive skin preparation involves the use of a disinfectant agent such as povidone iodine or chlorhexidine solution. Povidone iodine, 2% iodine tincture, and chlorhexidine are the most commonly used skin antiseptic solutions. Povidone iodine solution is highly germicidal for gram-positive and gram-negative bacteria, viruses, fungi, protozoa, and yeasts.7 It rapidly reduces bacterial counts on the skin surface and these effects last up to 3 hours.7,11 Allow the iodine solution to dry and then wipe it from the skin with 70% alcohol prior to beginning the procedure. The iodine solutions work by oxidation and cross-linking of sulfhydryl groups, killing bacteria as the solution dries. Isopropyl alcohol can be applied to the skin and scrubbed vigorously for 2 minutes to achieve disinfection, although this may cause skin irritation. Chlorhexidine or hexachlorophene preparations may be routinely used or as substitutes in iodine allergic or sensitive patients. These agents provide good bactericidal activity against gram-positive bacteria but somewhat less activity against gram-negative organisms.8 Chlorhexidine-based solutions are being used more commonly and are replacing the iodine-based solutions. Chlorhexidine
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provides much longer antimicrobial activity (up to 48 hours) and is more gentle on the skin than iodine.11–15 Chlorhexidine destroys cell membranes of gram-positive and gram-negative bacteria while precipitating the intracellular contents. Some preparations contain 70% isopropyl alcohol, further enhancing the antimicrobial activity.12–14 The use of chlorhexidine solutions is proving to be superior to iodine solutions.14,15 Use a skin disinfectant for procedures other than simple venipuncture. Place the disinfectant solution onto either a sterile sponge or sterile gauze if it is not supplied inside a single-use applicator. Historically, the application of disinfectant to the skin is in a circular motion, beginning with the central area of the procedure and working out toward the periphery of the sterile field (Figure 2-1). There is no evidence to support this application method. It has been suggested that scrubbing in a back-and-forth motion creates friction to dislodge microbes and may be preferable to the traditional circular application.9,10 The back-and-forth motion drives the disinfectant solution into skin crevices and deeper layers, thus killing more bacteria and hopefully preventing infections. Regardless of the disinfectant solution used, repeat the application process three or four times using a new sponge, gauze square, or applicator each time.8 This technique ensures that the central area where the procedure is to be performed is the most sterile area of the field. The area of disinfection must be much larger than the primary area of the procedure, as the number of organisms increases toward the periphery of the prepped area.
STERILE TECHNIQUE General sterile technique is described, followed by specific details for each step of the procedure. Strict sterile technique is virtually impossible in the ED. However, make every effort to maintain a sterile field in order to minimize infection. Assemble all equipment necessary and place it on a small procedure stand. Do not use the patient or their bed to set up supplies or equipment. Patient movement and their irregular body surfaces can result in items falling, breaking, becoming contaminated, or iatrogenic needle sticks. Avoid having different components scattered around the procedure area. Open all sterile items, using proper sterile protocol, so as to have them available once the physician has donned sterile gloves. Use anesthetic solution containers with removable caps. This allows the physician to draw up anesthetic without having an assistant and minimizes the risk of occupational needle exposure. Perform a thorough hand washing before the procedure. Apply sterile gloves. Place sterile drapes or towels to form a field wide enough to allow for a comfortable work space. Drape the area near the patient closest to the bedside procedure table. This will minimize inadvertent contamination in moving from the table to the patient. Make a small flat sterile area near the procedure site to allow for placement of important items that must be immediately available. Open all caps, position stopcocks, and prepare all devices prior to starting the procedure. The likelihood of contamination increases if devices are not adequately prepared, thus requiring manipulation during the critical portion of a procedure. Adhere to universal precautions guidelines. Use eye and face protection during the procedure. This should be applied before donning gowns and gloves.
OPENING A STERILE PACK Always make sure that the outer wrapping is intact, the sterility expiration date has not passed, and the sterility indicator tape is the appropriate color before opening a sterile pack.2 Wash your hands and then remove the outer wrap if applicable. Remove the sterility
FIGURE 2-1. Preparation of the skin. Disinfectant solution is applied in a concentric circular pattern starting from the procedure site and working outward. Apply the disinfectant solution with sterile gauze held in a clamp (A), with sterile gauze held in a sterile gloved hand (B), or with a sponge on a stick (C).
indicator tape (Figure 2-2A). Place the sterile pack on a dry and level surface with the outermost flap facing away from you (Figure 2-2B). Grasp the corners of the outermost flap (Figure 2-2B). Hold your arms to the sides of the pack to avoid reaching over the sterile area. Lift the flap up and away from you (Figure 2-2B). Open the side flaps by grasping the folded corner with a thumb and index finger
CHAPTER 2: Aseptic Technique
A
B
C
D
E
and pulling the flap to the side (Figure 2-2C). Open the bottom flap (Figure 2-2D). Grasp and open the bottom flap while stepping back to prevent contaminating the wrap on your clothing (Figure 2-2E). Make sure that your arms and clothes do not contaminate the contents of the pack when opening the flaps. Repeat the procedure if the pack has an inner wrap.
9
FIGURE 2-2. Opening a sterile pack. A. Remove the sterility indicator tape. B. Grasp the edges of the outermost flap and open it away from you. C. Open the side flaps. D. Open the remaining flap toward you. E. The open pack.
PLACING STERILE SUPPLIES ON A STERILE FIELD Sterile supplies are generally packaged in either a hard (hard pack) or a soft peel-back (soft pack) container. The general principle of opening these is the same, although there are subtle differences. Hold the hard peel-back container in the nondominant hand with
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A
B
FIGURE 2-3. Opening a hard peel-back container. A. Grasp the container with the flap facing the sterile field. Remove the flap. B. Drop the contents of the hard container onto the sterile field.
the flap facing the sterile field (Figure 2-3A). Pull the flap toward you with the dominant hand so that the open end of the pack will be facing the field (Figure 2-3A). Hold the container 15 to 20 cm above the sterile field. This ensures that if the contents fall, it will be onto the sterile field where they are wanted. Drop the contents of the sterile pack onto the sterile field, taking care not to contaminate the field with the container itself (Figure 2-3B). Gloves and syringes are wrapped in soft packs. Grasp both sides of the unsealed edge of the soft pack and pull them apart slightly (Figure 2-4A). Hold the open end facing the sterile field (away from you). Continue to open the soft pack. Fold the sides of the sterile packing back and over your hands to keep the contents sterile (Figure 2-4B). Gently drop the contents of the soft pack onto the sterile field.
APPLICATION OF A MASK Surgical masks serve a dual role in the performance of aseptic technique. Masks have been shown to decrease contamination of the sterile field that may result from aerosolized droplets from the mouth and nose. Masks protect the caregiver’s mucous membranes from exposure and possible splashing during the procedure. Wear a mask with an eye shield during high-risk procedures.
A
Apply the mask before donning gloves and other sterile equipment. Depending on the type and style of the mask, secure it by placing the elastic straps around the ears, placing the elastic straps around the head, or tying the mask securely to the face with ties around the head and neck. Pinch the metal nose clip securely to the bridge of the nose for a tighter fit and to minimize the gap between the mask and the nose.
HAND WASHING A physician must thoroughly wash their hands despite the fact that sterile gloves are worn for all sterile procedures. Good hand washing technique should not be overlooked. A full surgical scrub is neither necessary nor feasible in the ED. Rinse your hands in warm water prior to applying antiseptic soap. Apply soap, lather your hands, and rub them together vigorously for approximately 10 seconds. Wash each wrist with the opposite hand. Interlace the fingers of both hands and slide them back and forth to clean the web spaces. Clean around the nails with the fingertips and nails of the opposite hand. Completely rinse each hand from the fingers downward. Repeat the procedure a second time if your hands were grossly contaminated. Dry your hands with a disposable towel. Turn off the faucet, using the towel with which you dried your
B
FIGURE 2-4. Opening a soft peel-back container. A. Grasp both sides of the unsealed edge and pull them apart. B. Face the pack toward the sterile field. Continue to open the edges until the contents fall onto the sterile field.
CHAPTER 2: Aseptic Technique
hands. Do not touch the faucet with clean hands. Otherwise they will become contaminated again.
APPLICATION OF A CLEAN GOWN A clean (nonsterile) gown is often used as an additional barrier to contamination of both the field and the provider’s clothing. Simply place your arms into the sleeves and pull on the gown with the opening toward the back. Secure the gown at the back of the neck and the lower back by tying the strings.
APPLICATION OF A STERILE GOWN A sterile gown is worn for procedures requiring a stricter sterile technique (i.e., central venous access, diagnostic peritoneal lavage). To open a sterile gown, use the procedure previously described to open a sterile soft pack. Grasp and pick up the gown just below the neckline, touching only the inner surface of the gown. Hold the gown up and let it unfold with the inside facing you. Do not allow the gown to touch any nonsterile surfaces. Insert your arms into the sleeves until the gown is in place. Have an assistant grasp the back of the gown, pull it completely on, and tie the strings securely.
11
APPLICATION OF STERILE GLOVES Wash your hands thoroughly before putting on sterile gloves. Apply a clean gown at this point if it will be worn during the procedure. Open the outer wrap of the sterile gloves and remove the inner wrap (Figure 2-5A). Place the inner wrap on a clean surface with the gloves’ wrists facing toward you. Unfold the inner wrap, touching only the outside edges (Figure 2-5B). Open the inner wrap according to the procedure for opening a sterile pack (Figure 2-5C). Apply a sterile gown at this point if it will be worn during the procedure. Use the dominant hand to grab the opposite glove at the inner edge of its folded cuff (Figure 2-5D). Slip the nondominant hand into the glove, being careful not to touch the outer surface of the glove (Figure 2-5E). Pull the glove further onto the nondominant hand using the inner edge of the cuff (Figure 2-5F). Place the fingers of the gloved nondominant hand into the folded cuff of the other glove (Figure 2-5G). Slip the dominant hand into the glove (Figure 2-5H). Pull this glove over the dominant hand using the cuff (Figure 2-5I). Carefully unfold the cuff of each glove, taking care not to touch the fingers and palms of the gloves to nonsterile skin. Adjust each glove to ensure a snug fit over the fingers and hand.
A
B
C
D
E
F
G
H
I
FIGURE 2-5. Application of sterile gloves. A. Open the outer wrap and remove the inner wrap. B. Unfold the inner wrap. C. Completely open the inner wrap. D. Grasp the cuff of a glove. E. Slip the glove onto the hand. F. Pull the glove onto the hand. G. Slip the gloved hand into the folded cuff of the second glove. H. Slip the glove onto the hand. I. Pull the glove onto the hand.
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A
B
D
C
E
FIGURE 2-6. Removal of protective clothing. A. Untie the gown. B. Remove the gown by turning it inside out. C. Roll up the gown with the contaminated side facing inward. D. Remove the glove from the nondominant hand. E. Remove the glove from the dominant hand. Remove the face mask and wash your hands.
REMOVAL OF PROTECTIVE CLOTHING Remove protective clothing in a systematic manner in order to protect yourself and others from the contaminants on your gown and gloves (Figure 2-6). Place all removed garments into appropriate waste containers. The first step is to untie the gown (Figure 2-6A). Have an assistant untie the neck strings of the gown or pull on both shoulders of the gown to break the neck strings. Untie the waist strings. Take off the gown by turning it inside out as it is removed (Figure 2-6B). Roll up the gown with the contaminated surface facing inward and away from you (Figure 2-6C). Dispose of the gown. Remove the gloves by turning them inside out, making sure that you do not touch the outside (contaminated) surface with your ungloved hands. Use the dominant hand to grasp the cuff of the glove on the nondominant hand (Figure 2-6D). Pull the glove inside out as you remove it and throw it away. Place the ungloved fingers of the nondominant hand into the inside edge of the gloved dominant hand and remove it by pulling the glove inside out (Figure 2-6E). Dispose of the glove. Remove the mask by untying its ties or removing the elastic straps from behind your ears. Dispose of the mask. Finally, wash your hands.
COMPLICATIONS Properly performed aseptic technique has very few complications. The primary risk is in patients with sensitivities or allergies to latex or the disinfectant preparations. Although povidone iodine preparations are much less irritating than tincture of iodine, it is a good policy to clean all disinfectant off the patient at the end of the procedure so as to minimize any skin irritation. This is especially true of small children. Use alternate products for those patients with histories of allergies. The main complication of improper aseptic technique is infection at the site of the procedure.8 This only serves to underscore the need to perform aseptic technique properly.
SUMMARY Aseptic technique is an important component of all invasive procedures performed in the ED. Adequate skin disinfection and the proper use of sterile technique will greatly decrease the risk of iatrogenic infections. Aseptic technique allows a degree of protection for the caregiver as well as the patient.
CHAPTER 3: Basic Principles of Ultrasonography
3
Basic Principles of Ultrasonography
Patient
Treating physician
Gregory M. Press Bedside ultrasound
INTRODUCTION Emergency Physicians (EPs) have performed bedside ultrasound (US) for more than three decades. Today, US is ubiquitous in our specialty. Each year new physicians learn the skill, fresh evidence is brought to light supporting the practice, and novel indications are explored. Technological advances have delivered smaller machines with improved image quality that are less expensive than ever before. Several US manufacturers have developed machines targeted to Emergency Medicine (EM), taking into consideration our specific indications and less-than-forgiving work environment. US training is an important component of Emergency Medicine residency programs and a required core competency procedure of the Accreditation Council for Graduate Medical Education Residency Review Committee.1 There are numerous opportunities for supplementary training in emergency US, ranging from local courses to established fellowship training programs. Safety considerations have also contributed to the acceptance of bedside US. Sonography is noninvasive, safe in pregnancy, and does not require contrast agents that risk kidney failure, subcutaneous extravasation, and allergic reactions.2 With increasing concern in the medical community over the long-term effects of ionizing radiation, US is recognized as an attractive alternative.3 Additionally, the U.S. Department of Health and Human Services’ Agency for Healthcare Research and Quality has highlighted US guidance for central line insertion as 1 of their top 10 recommended practices.4 The intent of this chapter is to provide an introduction to bedside US for the EP. The physician-sonographer should have a general understanding of the physics underlying the properties of an US wave. “Knobology” is a colloquial term used to describe the study of the buttons, dials, switches, and, of course, knobs, on the console of an US machine. It is important that all users have a good sense of their machine’s operational functions. Typical machines and transducers used in the ED will be described.
THE PARADIGM OF BEDSIDE US Bedside US is a relatively new paradigm in clinical medicine. Traditional radiology US involves a break in the patient–physician encounter. The multistep process involves the EP evaluating the patient and determining that an US is warranted, the radiologic technologist performing the study in an US suite, the radiologist reviewing the images and generating a report, and the EP ultimately correlating that information back to the patient (Figure 3-1). Bedside US crafts a direct and immediate relationship between patient and EP (Figure 3-1). The technology is placed in the EP’s hand for both image acquisition and interpretation. The EP can immediately synthesize US findings with clinical and laboratory data to paint a more complete diagnostic picture. A patient’s condition can change on a moment’s notice in the ED, and, fittingly, US is a dynamic tool that can be used swiftly and serially throughout a patient’s course. In the early years of emergency US, EPs often used large tank-like machines that were not conducive to a fast-paced work environment. The evolution of US has delivered small portable machines that produce high-quality images. Many US devices are the size of laptop
13
Treating physician
Sonographer
Radiologist FIGURE 3-1. The paradigm of bedside US. The workflow of traditional US utilizing the radiology department (blue circle with red arrows) is a multistep process that may take hours to days to complete. Bedside US (double yellow arrow) establishes an immediate and direct interaction between patient and physician. (Courtesy of Christopher Moore, MD, RDMS, RDCS.)
computers that fit on maneuverable carts. “Pocket-sized” machines, not much larger than mobile phones, are being introduced and offer even greater portability (Signostics, Palo Alto, CA; GE Corporation, Fairfield, CT). The notion of the “sono-stethoscope” promises devices as small, easy to use, and available as the stethoscope, but with the superior insight of sonography. This device speaks to a true paradigm shift in clinical medicine.
INDICATIONS The primary indications of emergency US have traditionally included: cardiac US for the presence of pericardial fluid and for cardiac activity; abdominal US for the identification of free peritoneal fluid; aortic US for abdominal aneurysms; biliary US for the detection of gallstones and cholecystitis; renal US for hydronephrosis and nephrolithiasis; and pelvic US for the identification of an intrauterine pregnancy and the exclusion of an ectopic pregnancy (Table 3-1). Basic emergency US has operated on the binary premise that emergencies are to be included or excluded by this diagnostic tool. As the field has developed, the boundaries between primary and secondary indications have blurred, and the yes/no equation for the evaluation of emergencies has matured. TABLE 3-1 The Indications for Emergency Ultrasonography Primary indications Secondary indications Procedural indications Abdominal Abscess Arthrocentesis Aorta Deep vein thrombosis Foreign body localization Biliary Gastrointestinal Lumbar puncture Cardiac Genital Nerve blocks First trimester pregnancy Lung Paracentesis Renal Musculoskeletal Pericardiocentesis Ocular Thoracentesis Shock Transvenous pacer Other placement Vascular access Other
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The list of indications for present-day emergency US is long and continually expanding (Table 3-1). Other common indications include the evaluation for deep vein thrombosis. Lung US can be used to diagnose pneumothorax, pleural fluid, and interstitial lung diseases. US evaluation for abscesses, primarily subcutaneous but also peritonsillar, deep-space, and abdominal is common. Ocular US can be used to identify a retinal detachment, lens dislocation, vitreous hemorrhage, foreign bodies, and optic nerve sheath assessment for increased intracranial pressure. Patients in shock or hypotensive may be evaluated by US of the inferior vena cava and internal jugular veins to estimate central venous pressure. Gastrointestinal US is used for the identification of appendicitis, pyloric stenosis, and other conditions. Male and female genitourinary US is used to assess for testicular and ovarian torsion, intrauterine pregnancy, and ectopic pregnancy. Musculoskeletal US is used to diagnose joint effusions, tendinopathy, and fractures. Procedural US is used for guided assistance of vascular access, paracentesis, thoracentesis, pericardiocentesis, arthrocentesis, lumbar puncture, foreign body removal, nerve blocks, and other procedures.
Compression
Rarefaction
FIGURE 3-2. The longitudinal US wave. A force exerted in a parallel fashion along a coil will produce regions of compression and rarefaction. The particles of a sound wave vibrate in the direction the wave travels to create areas of high and low density and pressure. A sound wave is depicted as a classic waveform with peaks representing compression and valleys representing rarefaction.
US PHYSICS HISTORY Bats and toothed whales have used sound for echolocation for millions of years. Dolphins produce a series of clicks that pass through the lipid-rich melon on their heads, an acoustical lens of sorts that focuses the sound waves into a beam. Returning echoes are processed to determine the location of objects for navigational and hunting purposes.5 Sonar (acronym for sound navigation and ranging) is a maritime technique that uses sound waves for identifying oceanic objects. It was initially introduced in response to the sinking of the Titanic in 1912.6 It was further developed and employed in World War I for submarine detection.6 In the early 1950s, a radiologist named Douglas Howry and a team of other physicians introduced the first diagnostic US machine using a water-bath immersion tank. In the 1960s, direct contact (probe to patient) scanners were developed, and the contemporary saga of US as a viable diagnostic modality commenced.7
SOUND Sound is a variation in pressure traveling through a medium and it is described as a wave. We commonly understand the sound of our vocal communication to travel through air, but sound may also travel through fluid and solid structures. Pressure variations produced by sound waves mechanically displace or oscillate the particles of the medium. This oscillation produces cycles of higher and lower densities, or compression and rarefaction, respectively. Sound waves differ from water waves in that they are longitudinal, meaning the cycles of compression and rarefaction travel in the same direction as the wave. Imagine an analogous spring coil with a force exerted into its length. A wave, or region of compression, will pass down through the coil in a longitudinal or parallel fashion (Figure 3-2). It is important to have an understanding of the terms that describe sound waves as described in the following sections.
human hearing is approximately 20,000 Hertz (Hz), beyond which is considered “US.” Diagnostic US frequencies are generally in the range of 1 to 10 million Hz or MHz. US transducers operate on either the “low” or “high” end of this frequency spectrum, although for each transducer frequency can be adjusted within a limited range. Frequency is a principal determinant of the resolution and penetration of an image. Period is the time required for one cycle to occur. Thus, it is the inverse of frequency (Figure 3-3). In ultrasonography, period is typically measured in microseconds (µs).
WAVELENGTH AND PROPAGATION SPEED While period measures the duration in time of a single cycle, wavelength measures the distance in space of a single cycle (Figure 3-3). Wavelength is related to the propagation speed and the frequency of a wave. It is represented by the following equation: wavelength = propagation speed/frequency. Propagation speed is the velocity at which sound travels through tissue. An average speed through soft tissues of 1540 m/s is generally assumed in basic US. Newer US machines incorporate the propagation speeds of different tissues to provide enhanced imaging.
Amplitude
FREQUENCY AND PERIOD Frequency is the number of cycles of pressure variation per 1 second. A single cycle begins at a baseline of absent sound, increases to a maximum value (compression), decreases to a minimum value (rarefaction), and returns to baseline (Figure 3-2). Frequency is measured in hertz with a unit of cycles per second and corresponds to the pitch or tone of a sound. The upper acoustical frequency of
Period (µs) or wavelength (mm) FIGURE 3-3. The characteristics of an US wave. Period is the duration in time of a single cycle of a wave, while wavelength is the distance in space. Amplitude measures the wave’s variation (height) from baseline.
CHAPTER 3: Basic Principles of Ultrasonography
15
AMPLITUDE, OUTPUT, AND BIOEFFECTS Amplitude is a measure of the height or maximum variation of a wave from baseline (Figure 3-3). While frequency corresponds to the pitch or tone of a sound, amplitude is the “loudness” or volume of a sound. In US, this correlates to the brightness of the image. Adjustments of the machine’s output affect the amplitude, but changing the gain produces a similar effect on received echoes. It is preferable to alter brightness on the back end with gain, rather than subject the patient to increased output. While diagnostic US has proven to be exceedingly safe, concerns do exist over possible thermal and mechanical adverse bioeffects.8 EPs should strive to perform studies in the shortest time frame and at the lowest output possible, in line with the safety acronym ALARA (as low as reasonably achievable).
PULSED US The earliest US machines produced a continuous stream of US waves. Today’s machines release pulses or packets of waves, that is, a few cycles of US at a time. The repetitive pulses are separated by gaps of no sound. Machines can generate pulses of varying duration, frequency, and fraction of time with respect to the soundless gaps. Pulsed US has been essential in the development of advanced imaging.
AXIAL RESOLUTION Axial resolution refers to the ability of the US machine to distinguish two separate structures that lie on top of one another and in a parallel plane to the US beam (Figure 3-4). As viewed on the screen, this is one structure on top of another. The structures must
FIGURE 3-5. The lateral resolution of structures. Blue curves represent the transmitted US beam. Black curves represent the returning echoes. The structures must be able to produce separate echoes for the US machine to distinguish them. Focusing of the beam width improves lateral resolution.
produce two separate echoes for each to be recognized as distinct. The smaller the wavelength of the transmitted US beam, the closer in position can be the two tiny distinguishable structures. The size of the wavelength can be decreased by increasing the frequency of the US beam. Increasing the frequency delivers greater axial resolution. But a sacrifice is seen in penetration because of increased attenuation at higher frequencies.
LATERAL RESOLUTION AND FOCUS Lateral resolution refers to the machine’s ability to distinguish two separate structures that lie side-by-side in a plane perpendicular to the US beam (Figure 3-5). As seen on the screen, this is one structure to the side of another. Lateral resolution is a function of the beam width. The narrower the beam, the greater is the ability to produce separate echoes for two adjacent objects. Focusing narrows an US beam at specific depths. The focal zone is the narrowest part of the hourglass-shaped US beam. Focusing can be achieved automatically by the machine or manually by the operator. One or multiple focal zones can be set at specific depths to narrow the beam for optimal lateral resolution.
TEMPORAL RESOLUTION Continuous US scanning is actually a collection of still frames displayed rapidly over time. US machines produce numerous frames per second as the scan beam is transmitted over and over again through the tissue. The number of frames per second is known as the frame rate. The greater the frame rate, the better the temporal resolution, and the smoother the moving image appears. High frame rates are particularly important for scanning moving structures such as the heart. Employing additional functions such as Doppler scanning may limit the machine’s ability to produce high frame rates.
ECHOES
FIGURE 3-4. The axial resolution of structures. Blue curves represent the transmitted US beam. Red and black curves represent the returning echoes of the superficial and deep structures, respectively. Increasing the frequency, which shortens the wavelength, improves axial resolution.
Diagnostic US is predicated on sound waves not only transmitting through tissues but also reflecting back to the transducer (Figure 3-6). At an interface of two different tissues, the proportion of transmission and reflection is determined by the acoustic impedance of the tissues. Acoustic impedance is a measure of a tissue’s resistance to sound penetration (density × propagation speed). Acoustic impedance is high in “hard” tissues such as bone, lower in visceral organs, and negligible in fluid. Reflection of an echo is a function of the difference between the acoustic impedance of two
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FIGURE 3-6. The echoes produced as the US beam penetrates tissue. The transmitted beam (orange) attenuates as it penetrates. A reflected echo (green) is produced at an interface. Refraction (purple) and scatter (brown) contribute to attenuation. Scatter produces the imaging within homogenous tissue.
adjacent tissues. For instance, when a sound wave travels from soft tissue to bone, a significant proportion of the wave will reflect back to the probe, and a minimal amount will transmit through for imaging of deeper structures. When an US beam travels through parenchymal tissue without interfaces (of homogenous acoustic impedance), such as the liver, imaging is generated not by reflection but rather by scatter. Scattering occurs when a sound wave encounters particles smaller than its wavelength or objects with rough and irregular surfaces. An analogous effect is seen when light is shone through fog. There is some transmission and reflection of the light, but it is the scattering of light that reveals the mass of fog. In order for an US machine to generate an image, it must determine not only the intensity of the returning echo but also the location of the reflecting structure (aka reflector). With a given propagation speed (velocity of sound through tissue), the machine uses the travel time of the sound wave to calculate the distance the reflector sits from the transducer. The longer the travel time, the deeper is the reflector or structure.
ATTENUATION Sound weakens or attenuates as it propagates through a medium (Figure 3-6). Attenuation is a result of absorption, reflection, refraction, and scattering of the US wave. Absorption is the conversion of sound to heat as the wave passes through tissue and accounts for
FIGURE 3-7. The Press-ervation technique for transducer cords. Segments of a coiled garden hose are sliced along their length and placed around the middle portion of a transducer cord. This prevents damage from wheels running over dangling cords.
the vast majority of attenuation. Absorption has very limited clinical effect for diagnostic US but is the basis of therapeutic US. Reflection is the “echoing” of the wave back to the transducer. Refraction and scattering are the redirection of waves on encountering certain interfaces.
US TRANSDUCERS (PROBES) There are many types of transducers (also called probes) that vary in size, shape, construction, transmitted frequency, and function (Table 3-2). Transducers can be expensive and are at risk for damage in a busy ED. Probes are often dropped and cords frequently run over by the wheels of the US machine. Creative solutions to prevent damage to dangling cords have been developed (Figure 3-7), but the expense of replacing transducers should be factored into
TABLE 3-2 Common Types of US Probes Used in the ED Transducer type Vascular Transducer shape
Abdominal
Endovaginal
Cardiac
Type of scanning Transducer frequency Megahertz
Curved sequenced Low 2–5
Microcurved sequenced High 7–100
Phased array Low 2–5
Linear sequenced High 7–10
Photographs courtesy of Zonare Medical Systems.
CHAPTER 3: Basic Principles of Ultrasonography
any warranty and maintenance considerations. Many US manufacturers offer multiport transducer connections that allow a number of probes to be connected at once, each activated by the push of a button. Limiting the connecting and disconnecting of transducers decreases the chance of damaging fragile connector pins. Transducers are the link between the US machine and the patient. The essential component of the transducer for generating an image is the piezoelectric element. The piezoelectric principle states that when an electrical voltage is exerted on certain materials, a mechanical pressure or vibration will be produced. A transducer’s piezoelectric elements, or crystals, when vibrated by an electrical voltage will generate a mechanical sound wave. The returning sound wave in turn vibrates the elements creating an electrical voltage that carries image data back to the US machine.
AUTOMATIC SCANNING Transducers are constructed of numerous elements arranged along the width of the probe. Unlike a flashlight that emits a single continuous beam of light, the US beam is a composite of pulsed firings of the elements. Automatic scanning is the electronic activation of the elements or arrays of crystals to generate a beam for a cross-sectional image. Two types of automatic scanning currently employed by transducers are sequenced array and phased array scanning.
SEQUENCED ARRAY Sequenced array scanning involves the sequential firing of groups of elements across the transducer assembly (Figure 3-8). One scan line after another is generated along the width of the probe. Linear transducers are flat-topped and produce a rectangular beam made up of parallel scan lines. Curved transducers transmit scan lines similarly, but following the curve of the probe and create a sector or pie-shaped image. The elements are fired rapidly and multiple frames of cross-sectional images are produced per second.
PHASED ARRAY Phased array transducers generally have a narrow flat-topped footprint. The tightly packed elements are electrically activated as a single unit, but with a slight time lag between each element resulting in an angling of the pulse direction. The electronic activation and angling of each subsequent pulse is slightly changed, and the resultant composite beam is a sector or pie-shaped (Figure 3-8).
Linear sequenced
Curved sequenced
Phased array
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TRANSDUCER TYPES The typical arsenal of transducers for emergency US includes a lowfrequency curvilinear or phased array probe, a high-frequency linear probe, and an endocavitary probe (Table 3-2). Numerous other types of transducers are manufactured. It is worthwhile evaluating the options available before purchasing a transducer.
CONVEX TRANSDUCERS Convex or curved transducers are low-frequency probes that produce a sector-shaped image by sequenced array scanning. These are commonly used in EM, as they are useful for most US examinations of the torso. The resolution of these probes is inferior to that of linear transducers, but the greater penetration allows for imaging of relatively deep structures such as the aorta, gallbladder, liver, kidneys, and heart. Microconvex probes have a similar but smaller footprint with a tight curvature that allows for easier use between adjacent ribs.
PHASED ARRAY TRANSDUCERS Phased array transducers are low-frequency probes made for echocardiography and general imaging of the torso. These probes have a small flat footprint ideal for maneuvering between ribs and imaging the heart.
LINEAR TRANSDUCERS Linear transducers are high-frequency probes that are ideal for imaging superficial structures. They are generally wide and flattopped, and produce a rectangular image by sequenced array scanning. These transducers are useful in the ED for imaging of blood vessels and guided line placement, skin abscesses, musculoskeletal pathology, pneumothoraces, ocular and testicular pathology, and a host of other superficial parts.
ENDOCAVITARY TRANSDUCERS Endocavitary transducers are high-frequency probes that have elements arranged in a tight curve at the end of a long handle. They are designed primarily for vaginal insertion and high-resolution imaging of the female reproductive organs. These probes can be used for US-guided vascular access if no other high-frequency probe is available. The small footprint and room afforded by the handle may even prove superior to a linear probe in some instances. The probe can be used in a patient’s mouth for the evaluation of oral and pharyngeal pathology, such as a peritonsillar abscess.
FREQUENCY AND TISSUE HARMONIC IMAGING
FIGURE 3-8. The basic types of transducers. Linear sequenced and curved sequenced array probes transmit beams in a sequential fashion following the shape of the transducer head to produce rectangular and pie-shaped images, respectively. The beams of phased array probes are steered by slight delays in the firing of the elements to produce a pie-shaped image.
Transducers may differ in inherent frequency. The frequency of each probe can be adjusted within a narrow range of generally a few megahertz. If greater depth is required to view pertinent structures, lowering the frequency may be beneficial. Conversely, if finer resolution is desired more than deep penetration, increasing the frequency may improve visualization. Tissue harmonic imaging is another means of enhancing US scanning. US echoes return from tissues in multiples of the transmitted frequency. The machine can filter out the transmitted frequency and focus on receiving the second harmonic frequency (twice the transmitted frequency). The returning harmonic beam is narrower than the beam of the fundamental frequency, and, hence, lateral resolution is improved. Artifacts and distortions are also reduced with harmonic imaging.
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LCD display monitor
Speakers & microphone Adjustable height control panel
US probes
Scan engine Docking deck On/off button
Multi-transducer port
CD/DVD drive Printer bay Swivel wheels with locks
FIGURE 3-9. Components of a typical US machine.
COUPLING MEDIUM
GAIN
Acoustic gel is the coupling medium used in diagnostic US. The gel obviates any air between the probe and the patient to improve US beam transmission. Apply the gel across the footprint of the probe or onto the patient’s skin. A good rule of thumb is that too much gel is preferable to too little.
Gain is the US analog to the volume control on a radio. It alters not the transmitted beam, but the returning echo to amplify intensity. Gain is measured in decibels and relates to the brightness of the image. Machines generally have a knob that can be dialed to adjust the gain, increasing or decreasing the overall brightness of the image (Figure 3-10). Time gain compensation (TGC) allows for adjustments of gain at specific depths. Most TGC controls consist of a collection of sliding knobs arranged in a column (Figure 3-11). The knobs at the top of the column correspond to the near field and those at the bottom correspond to the far field. As an US beam penetrates to greater depths, the intensity of the beam is attenuated or dampened. TGC allows compensation for attenuation. For general abdominal imaging, arrange the sliding TGC knobs with a slope of increasing gain at greater depths. Use TGC to increase or decrease brightness at discreet depths of the image. To compensate for the artifactual brightness seen deep to a fluid-filled structure, decreasing the gain at that depth can improve visualization.
ULTRASOUND MACHINE INSTRUMENTATION An US machine is made up of numerous components (Figure 3-9). The imaging system hardware consists of a beam former, signal processor, and image processor. The console allows the user to interface with and manage the imaging. The monitor screen provides for black and white as well as color viewing of the imaging. Transducers, single or multiple, have connecting ports onto the machine. Archiving tools, such as a printer or digital storage media, are available standard or as options. The following sections review the key functions that an EP should know when performing US examinations.
THE CONSOLE The US console generally consists of a keyboard for data entry and numerous knobs, buttons, dials, and toggle switches for manipulating the images. Carefully read the user’s manual or undergo a detailed operations briefing by the manufacturer’s application specialist after purchasing a new machine. While there are many functions that are universal to US machines, each machine has its proprietary functions.
DEPTH The depth of the field of view can be adjusted by the turn of a dial or toggle of a switch. Depth is conventionally measured in centimeters. Hash marks along the side of the image denote units of distance. Depth adjustments alter the penetration of the imaging beam and allow the user to appropriately “magnify” the organ or region of interest (Figure 3-12). If the depth is set too shallow
CHAPTER 3: Basic Principles of Ultrasonography
19
A
FIGURE 3-11. Time gain compensation (TGC) controls on an US machine consist of a column of knobs that slide back and forth to adjust the gain at specific depths.
B
(“overmagnification”), the organ of interest will appear too large and its deepest portion may be cut off the screen. If the depth is set too deep (“undermagnification”), the organ of interest will appear too small in the near field with wasted space in the deeper regions.
PATIENT DATA ENTRY All machines allow the entry of demographic information about the patient and the US examination. The patient data entry screen presents numerous fields that can be filled by typing on the keyboard. These fields commonly include patient name, medical record number, date of birth, and a comments section to name a few. Functions also often available on this screen are exam and transducer selection.
FREEZE AND CINE Most machines allow both still images and video loops to be saved. Hitting the “freeze” button stops real-time continuous scanning. The most recent image is displayed on the screen with a few seconds worth of images (known as cine) available for review. Use the rollerball or trackpad to rewind through the cine memory of frames. This allows the viewing and subsequent saving of the most desired still image. A number of machines can allow the viewing of a loop of images as a video.
C FIGURE 3-10. Gain adjustments brighten and darken the US image. These images of a kidney display a gain setting (A) too low, (B) appropriate, and (C) too high.
MISCELLANEOUS FUNCTIONS There are numerous additional functions on the console. Magnify images with the “zoom” function. The “measure” button activates
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PRINCIPLES OF GENERAL US IMAGING DIMENSIONALITY Imaging with US is akin to shining a flashlight in the dark. While a flashlight’s beam is conical, the US beam is flat, and, hence, the image displayed on the screen is a two-dimensional slice. Sound transmits through most tissues to allow for visualization of deep structures in the cross-sectional slice. Scanning the beam back and forth stacks multiple two-dimensional slices in a movie format and provides a sense of spatial orientation. Rotating the probe 90° and scanning through the perpendicular plane helps to gain a threedimensional comprehension of structures.
A
ORIENTATION Orientation is entirely dependent on how the transducer is placed on the patient. Each transducer has a marker (usually a bump, ridge, or indentation) that correlates with an indicator on the screen to establish orientation. If the transducer is held with the marker aimed cephalad, the screen indicator is located on the left side of the screen (Figure 3-13). This results in the left side of
B
A
C FIGURE 3-12. Depth adjustments increase and decrease the penetration of the US beam. These images of a kidney display a depth setting: (A) too deep at 22 cm, (B) appropriate at 10 cm, and (C) too shallow at 6 cm.
calipers that are moved with the trackpad or rollerball. This allows for precise measurements to the millimeter. Adjust the dynamic range to produce effects similar to modifying the contrast of a photograph. Other functions include gray-scale mapping, edge, and persistence for image alteration. A dual screen function displays two side-by-side imaging fields. Function keys can be set for easy access to commonly performed tasks.
B FIGURE 3-13. The orientation marker (white arrow) on the transducer corresponds with the indicator on the screen (red arrow).
CHAPTER 3: Basic Principles of Ultrasonography
21
A
B
C FIGURE 3-15. Echogenic gallstones are present in the gallbladder. Shadowing is seen deep to the gallstones. D
E
FIGURE 3-14. Echogenicity of structures is represented by their brightness on the screen. A. Anechoic fluid is black. B. Echogenic, or highly reflective, than adjacent tissues. C. Isoechoic, or same echo-texture, as adjacent tissue. D. Hypoechoic, or less echoic (darker), than adjacent tissues. E. Hyperechoic, or more echoic, than adjacent tissues.
the image representing the cephalad aspect and the right side the caudal aspect (Figure 3-13). For conventional radiology imaging, the screen indicator is located on the left side. Most emergency US examinations require views with the transducer marker aimed to the patient’s head and the patient’s right. The image is displayed with the near field (closest to the probe) at the top of the screen and the far field (farthest from the probe) at the bottom of the screen.
echoes deep to a structure that is hyperechoic as the lack of reflection, similar to that seen with fluid. This is seen as a black shadow on the screen (Figure 3-15). While shadowing from ribs may obscure deep anatomy, the shadows of gallstones aid in their identification.
REVERBERATION Highly reflective interfaces may result in multiple reflections. Bouncing of the sound beam between the reflector and the transducer can create false echoes known as reverberation (Figure 3-16). It can be seen when the sound beam encounters two closely spaced interfaces, such as the two walls of a needle or the visceral and parietal pleura. The echo reflects back and forth between the interfaces, but with some transmission of the beam back to the probe each time. These returning echoes generate artifactual reflections on the screen termed reverberation or comet tails (Figure 3-17).
ECHOGENICITY Fluid is anechoic, meaning US transmits through fluid without any reflected echoes. The echogenic silence is processed to generate black pixels on the screen. Highly reflective structures, such as the diaphragm and pericardium, are termed echogenic or hyperechoic. These structures will produce white imaging. Two structures of the same echo-texture are isoechoic. Less reflective tissue is hypoechoic and appears darker on the screen when comparing two tissues (Figure 3-14).
ARTIFACTS Imaging artifacts are frequently encountered in ultrasonography. They are erroneous representations of the anatomy in the reflected echo. It is important to understand and expect certain artifacts to prevent misinterpretation of the images. Artifacts may also help to appreciate certain structures that would otherwise be less obvious.
SHADOWING A highly reflective object allows very little of an US beam to transmit through it. Most of the beam is reflected back to the transducer and the structure is represented as hyperechoic or white on the screen. The US machine interprets the lack of returning
FIGURE 3-16. The two walls (white arrows) of a cylindrical bullet are seen superficially. Reverberation artifact produces an additional false echo (red arrow). Shadowing is seen deep to the bullet.
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FIGURE 3-17. Each back and forth reflection between the visceral and parietal pleura (white arrow) results in an echo transmitted back to the probe. Multiple echoes returning one after another produce echogenic artifacts, each deeper than the next. The artifact resembles a comet tail (red arrow).
FIGURE 3-19. A mirror-image artifact (white arrow) of the spleen is seen cephalad to the diaphragm. This is distinct from fluid that appears black.
MIRROR IMAGE
MISCELLANEOUS ARTIFACTS
Highly reflective tissues can cause mirror-image artifacts. Structures seen on the near side of a bright reflector are displayed on the other side of the reflector as well. This is common with the diaphragm. Triangulation of the beam path delays the return time of the echo to mirror a second reflector (Figure 3-18). Mirror-image artifact can help to exclude a hemothorax by visualizing the liver or spleen cephalad to the diaphragm (Figure 3-19).
A number of additional artifacts can interfere with imaging. Side lobes are weak beams emitted lateral to the central axis of the scanning beam that may produce false echoes. Section thickness artifact is a result of interfering information from the outside of the flat slice of the scanning beam. Refraction of the beam tangentially off an interface may produce a double image of a structure lateral to the original. Shadowing in the narrow angle of refraction may be seen deep to the interface.
ENHANCEMENT Attenuation does not occur when a sound beam passes through a fluid-filled structure. The beam’s high intensity is maintained through the fluid. A strong echo is generated off the posterior wall of the fluid-filled structure. The artifact seen on the screen is a very hyperechoic region deep to the fluid-filled structure that may obscure the actual anatomy (Figure 3-20).
US MODES BRIGHTNESS MODE Brightness mode is commonly referred to as B-Mode. This is the basic scanning mode for US. It displays the standard twodimensional gray-scale image.
A
B
FIGURE 3-18. Bright reflectors like the diaphragm (white) can generate mirrorimage artifacts. The initial beam (solid arrow) reflects off the diaphragm and then an anatomical structure (A) before returning to the transducer. The machine processes the delay as a signal from a deeper structure along the initial scan line (dashed arrow) and generates an artifact (B) on the screen.
FIGURE 3-20. High-intensity echo returns from the posterior wall of the bladder result in a hyperechoic region of enhancement artifact (white arrow).
CHAPTER 3: Basic Principles of Ultrasonography
FIGURE 3-21. The M-Mode. The B-Mode image is displayed at the top of the screen. A green vertical line is seen over the B-Mode image. The area under the green line is displayed over time at the bottom of the screen. The fetal heartbeat is seen at a depth of 3.6 cm and measured at 153 beats/min.
23
FIGURE 3-22. The color Doppler box, or region of interest (ROI), placed over the carotid artery reveals flow in the direction of the probe (red).
PULSED WAVE DOPPLER MODE MOTION MODE Motion mode or M-Mode is used to assess moving structures. Activating M-Mode produces a vertical line on the image (Figure 3-21). The line can be moved left or right with the rollerball or trackpad. The US beam penetrating the tissue along that single line is displayed in a continuous graphical manner on the bottom of the screen (Figure 3-21). The x-axis of the display is depth and the y-axis is time. If the line is set on immobile tissue, there will be no variation in the M-Mode display. Movement along the line, such as a beating heart, allows measurements and rate determinations (Figure 3-21).
DOPPLER MODE Doppler scanning allows the assessment of the presence, direction, speed, and character of blood flow and tissue movement. Doppler takes full advantage of the real-time dynamic nature of US. If an object is moving toward or away from the transducer, the frequency of the reflecting echo will be higher or lower, respectively, than the transmitted frequency. The Doppler shift is the difference between the transmitted and reflected frequencies. The US machine can calculate velocity using the Doppler shift. Turbulence, or the variance in velocity of multiple objects in flow, can be assessed. The complexities of Doppler physics and operations are beyond the scope of this chapter. Emergency Physicians can utilize Doppler in the assessment of deep venous thromboses, testicular or ovarian torsion, compromised vascular flow in the extremities, inflamed or hypervascular tissues, to differentiate vessels from nonvascular structures for diagnostic and procedural purposes, and for advanced echocardiography.
Pulsed wave Doppler provides a quantitative assessment of flow velocities. Activating pulsed wave Doppler splits the screen, typically placing the image at the top of the screen and a dynamic graph of flow velocities at the bottom (Figure 3-23). A small “gate” can be positioned over a specific vascular area to measure flow. The size of the gate can be adjusted, allowing very narrow regions to be accurately assessed. The dynamic Doppler graph displays time on the x-axis and velocity on the y-axis. Movement toward the probe is depicted as a positive velocity deflection. Movement away from the probe is depicted as a negative deflection.
POWER DOPPLER MODE Power Doppler is another method of displaying blood flow or tissue motion (Figure 3-24). It utilizes the same ROI box as color Doppler, but with only one shade of color. Power Doppler is very sensitive in identifying the presence of flow but does not reveal direction. It is advantageous in identifying low flow states, subtle tissue motion, and imaging small or deep vessels.
COLOR DOPPLER MODE A “C” button on the machine’s console usually signifies color Doppler mode. Activating color Doppler produces a box, or region of interest (ROI), overlying the image. The ROI can be maneuvered over the desired area. The size of the box can be manipulated to be larger or smaller depending on the study being performed. Within the ROI, flow will be displayed in a color schematic (Figure 3-22). Flow toward the probe is typically red. Flow directed away from the probe is typically blue. Gradients of red and blue signify the speed of the flow.
FIGURE 3-23. The pulsed wave Doppler mode. A Doppler gate is placed over the center of the carotid artery. Flow is displayed in active graphical format at the bottom of the screen. Positive deflections indicate systolic flow in the direction of the probe.
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SUMMARY Ultrasound is fast becoming a commonly used modality in EDs. All EPs should become familiar with US as it will soon become the standard of care for patient evaluation, patient management, and procedural guidance. Take the time to investigate the various options available for machines, probes, and accessories. A thorough understanding of the functioning and features of an US machine is essential before making clinical decisions. Training is readily available through US fellowships, CME courses, and ultrasound manufacturers.
A
4
Ultrasound-Assisted Procedures Jehangir Meer, Sam Hsu, and Brian Euerle
INTRODUCTION
B FIGURE 3-24. The power Doppler mode. A. Normal lung slide at the pleural line. The tissue movement generates a power Doppler signal. B. No lung slide or tissue motion is seen in the setting of pneumothorax.
US IMAGE ARCHIVING There are numerous ways to archive US images. Still images can be sent to printers for hard copy archiving. Thermal printers are relatively small and can be attached to the US cart. The gray-scale printouts are fine reproductions of the image, but are at risk for degradation over time. Digital archiving allows users to save both still images and videos with a far reduced need for physical storage space. Examinations can be saved to hard drives built into the US machine or to peripheral devices. Machines today offer many options for peripheral storage including compact discs, digital video discs, external drives with universal serial bus connections, and magneto-optical disks. Specific formats for digital archiving of medical imaging have been developed, in particular the digital information and communication in medicine (DICOM) format. Most US machines today have the ability to save images in the DICOM file format. Picture archiving and communication system (PACS) has been developed for viewing medical imaging in DICOM and other formats. These systems are employed by radiology departments for viewing US images, as well as computed tomography, magnetic resonance imaging, plain radiographs, and other imaging modalities. Advantages to saving DICOM images on PACS include improved organization, reliability, and the ability to transmit remotely.
Emergency Physicians commonly perform invasive procedures. These procedures have traditionally been taught using surface landmarks, with the assumption that anatomy is reliably similar from patient to patient. The increasing use of ultrasound (US) to assist in procedural guidance has demonstrated that this is not the case. Utilizing US to assist with procedures has numerous benefits.1–9 It is safer for patients as it has been shown to reduce complications. US improves patient comfort and satisfaction. This is due primarily to decreased attempts at the procedure. The use of US usually decreases the duration of the procedure. This chapter reviews the basic information regarding the use of US to assist or guide procedures in the Emergency Department (ED). US can assist in many commonly performed ED procedures (Table 4-1). The specific US technique for a procedure is described in the chapter for the particular procedure. The sonographer must make several decisions prior to beginning a procedure using US. Will the procedure be performed under real-time US guidance or will US only be used to map the anatomy? Will one person (the sonographer) or two people (the
TABLE 4-1 Common ED Procedures that Use US Assistance or Guidance Body region Procedures Abdomen and pelvis Paracentesis Suprapubic bladder aspiration Suprapubic bladder catheterization Airway Endotracheal intubation Bones and joints Arthrocentesis Closed fracture reduction Fracture identification Chest Pericardiocentesis Thoracentesis Cardiac pacing (transvenous and transthoracic) ENT Peritonsillar abscess incision and drainage Nervous system Peripheral nerve blocks Lumbar puncture Soft tissue and Abscess identification musculoskeletal Abscess incision and drainage Foreign body identification and removal Vascular Arterial line placement Central venous access Peripheral venous access
CHAPTER 4: Ultrasound-Assisted Procedures
sonographer and an assistant) be necessary? Which US probe is the most appropriate for the procedure? Should the instrument or needle be imaged in the long-axis view or the short-axis view? Are needle guides necessary? What is the ideal location of the US machine in relation to the sonographer and patient? These general questions must be kept in mind when using US for invasive procedures and are discussed below.
US GUIDANCE VERSUS MAPPING
25
TABLE 4-2 Recommendations for the US Probe Type to Use for Specific Procedures Probe type Procedure Curvilinear Endotracheal intubation Lumbar puncture Paracentesis Pericardiocentesis Suprapubic bladder aspiration Suprapubic bladder catheterization Transcutaneous cardiac pacing Transvenous cardiac pacing Endocavitary Peritonsillar abscess incision and drainage Linear array Abscess incision and drainage Endotracheal intubation Fracture identification Fracture reduction Lumbar puncture Peripheral nerve blocks Phased array Pericardiocentesis Thoracentesis Transvenous pacing
US can be used in one of the two ways for procedural assistance: the dynamic technique or the static technique. The dynamic technique is also known as US guidance. The sonographer uses US guidance in real time during the procedure to survey the anatomy, to confirm a diagnosis, and to visualize the needle or instrument as it enters tissue and reaches the target. The static technique is also known as US mapping. The sonographer uses US mapping prior to starting the procedure to map the local anatomy, to confirm a diagnosis, and to mark the site of needle entry. The US probe is then put away and the procedure performed in the traditional fashion without real-time US. The decision between US guidance versus US mapping is influenced primarily by the degree of inherent danger of the procedure. Perform procedures that carry a higher risk or have greater technical difficulty (e.g., central venous access, pericardiocentesis, or foreign body removal) under US guidance. Perform lower risk procedures (e.g., thoracentesis, paracentesis, or abscess I&D) with US mapping. Another factor is sonographer experience. The experienced sonographer is more technically adept and comfortable doing procedures under real-time US guidance. Novice sonographers who do not have as much psychomotor training and experience may find it easier to use US mapping.
probe and the phased-array probe (Table 4-2). High-frequency US probes include the linear probe and the endocavitary probe (Table 4-2). More than one probe may be required for some procedures. Another factor in selecting the US probe is its footprint or surface area. A larger footprint is recommended to get a larger scan image unless specific anatomic barriers (e.g., ribs) dictate a smaller footprint. The types of US probes recommended for specific procedures are listed in Table 4-2.
ONE-PERSON VERSUS TWO-PERSON TECHNIQUE
ORIENTATION OF THE NEEDLE AND THE US PROBE
The decision to perform a procedure with one or two people is based on the sonographers experience and the availability of an assistant. Sonographers with more experience often prefer to guide the US probe and manipulate the instrument themselves. Their experience and expertise allows them to work with a higher efficiency without an assistant. Assistance during the procedure may not be an option during a busy ED shift, in an ED with single physician coverage or in an ED with limited personnel. For one-person US guidance, the sonographer holds the US probe with the nondominant hand and guides the needle or instrument with the dominant hand. This requires a degree of hand-and-eye coordination to maintain continuous alignment of the needle with the US probe. Novice sonographers may find it less daunting to use the twoperson technique and work with an assistant. The assistant holds the US probe while the sonographer guides the needle or instrument. The assistant’s responsibility is to maintain alignment of the US probe with the needle during the procedure. The sonographer must maintain good communication with the assistant throughout the procedure in order to maintain sight of both the needle tip and the target organ on the US screen.
Two orientations or approaches are used for US guidance during procedures. The longitudinal or long-axis approach refers to placing the long axis of the needle in-line with the long axis of the US probe
TYPES OF US PROBES The following general principle will be helpful in determining which US probe is the most appropriate for a given procedure. The higher the frequency of the US probe, the better the resolution of the structures visualized, but the shallower the maximum depth of view. In other words, use a high-frequency US probe for superficial structures and a low-frequency US probe for deep structures. Low-frequency US probes include the curvilinear
FIGURE 4-1. The longitudinal or long-axis approach of the US probe to the needle.
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SECTION 1: Introductory Chapters
FIGURE 4-2. The transverse or short-axis approach of the US probe to the needle.
(Figure 4-1). The transverse or short-axis approach refers to placing the long axis of the needle 90° to the long axis of the US probe (Figure 4-2). It is paramount for the sonographer to keep sight of the needle regardless of which approach is used during the procedure. It is helpful to have the US probe indicator facing the same side as the marker on the top of the US screen to maintain left-to-right alignment. The long-axis approach allows the entire length of the needle to be visualized as it approaches the target (Figure 4-3). Depth perception is better with this approach. This is a more intuitive approach for some ultrasonographers. The main disadvantage of the long-axis approach is the poor lateral resolution. A needle located to the side of a structure may appear in the same plane as the structure when actually it is not. This approach requires precise alignment of the US probe with the needle, otherwise the sonographer can lose sight of the needle. The one procedure best performed with the long-axis approach is a peripheral nerve block. The short-axis approach requires the sonographer to center the target of interest on the US screen. The long axis of the needle is positioned 90° to the long axis of the US probe, at the center of the long axis of the US probe (Figure 4-2). The short-axis view of the needle is visible on the US monitor, resulting in better lateral resolution (Figure 4-4). One disadvantage of this approach is the challenge to maintain sight of the needle tip. The sonographer must move the US probe forward along with the needle tip as it is advanced. The depth of the needle tip can be misjudged if one is not careful. This can sometimes result in the inadvertent puncture of the anterior and/or posterior wall of the target structure or vessel, or of another adjacent structure.
FIGURE 4-3. Long-axis US view of the needle (arrows).
procedure. A needle guide is not necessary for the vast majority of Emergency Medicine procedures. It may actually be disadvantageous since it does not allow “on-the-fly” corrections of the needle path.
MECHANICAL NEEDLE GUIDES Needle guides are attachments to the US probe that keep the needle in a predictable path during the procedure. They are often utilized by radiologists for aspiration or biopsy of deep structures. The benefit of using a needle guide is that less hand-to-eye coordination is required to keep the needle aligned with the US probe during the procedure. The disadvantage of a needle guide is that the path angle is fixed and cannot be changed in the midst of the
FIGURE 4-4. Short-axis US view of the needle (arrow).
CHAPTER 4: Ultrasound-Assisted Procedures
27
FIGURE 4-5. An example of a good setup with the US machine in relation to the sonographer and the patient. FIGURE 4-6. Ring-down artifact (arrow) showing the hyperechoic vertical line originating from the needle tip.
GENERAL TIPS WHEN USING US GUIDANCE Always ensure that there is a direct line of sight from the procedural field to the US machine (Figure 4-5). The sonographer should not need to turn their head to the side during the procedure to view the US screen. This will greatly improve the sonographer’s comfort during the procedure and increase the likelihood of success. Having to turn your head back-and-forth can result in the needle or the US probe moving, an unsuccessful procedure, puncture of incorrect structures, and potential morbidity. Hold the US probe comfortably in the nondominant hand using a pencil-like grip and maintaining light contact with the patient. It is best to use short controlled movements to maintain visualization when manipulating a needle or other instrument under US guidance. Misalignment of the US probe and the needle is the most common reason for the needle tip not being visualized during the procedure. Stop advancing the needle if it is not visible on the US screen. Reposition the US probe by dragging or fanning it back and forth over the area of the needle until the needle can be seen. Gently rocking or bouncing the needle within the soft tissue can sometimes assist in determining the location of the needle tip. Indirect clues can help determine the location of the needle tip if it cannot be seen directly. These include the ring-down artifact (Figure 4-6) and the needle shadow artifact (Figure 4-7). The ring-down artifact is a bright hyperechoic streak due to reverberation of the US beam from the highly reflective interface of the needle. The shadow artifact is a hypoechoic line below the needle due to the needle blocking the US beam. Follow either artifact until the needle can be visualized on the US screen. Continue to follow the needle until the tip is found. Other factors can affect the ability to visualize the needle. Consider these when preparing to perform a procedure. Use the appropriate probe and depth of field for the procedure. Smaller gauge needles produce smaller artifacts and are more difficult to visualize, especially in cross section. It is easier to visualize needles perpendicular, or in the short axis, to the US beam. Consider using needles specific for ultrasonography that are extra reflective. The costs of these needles are hard to justify, but may be acceptable for teaching. Normal needles are appropriately reflective and it is difficult to justify these specific needles clinically. The beveled tip of the needle is easier to visualize than the shaft. The irregular surface of the bevel will reflect the US beam better than the shaft. Insert and advance the needle with a slight “to-and-fro” motion to easily follow the needle path.
SUMMARY The use of US assistance for procedures is an important skill set in the armamentarium of the Emergency Physician. It allows potentially dangerous procedures (e.g., incision and drainage of a peritonsillar abscess) to be performed in a safer manner due to visualization of the surrounding anatomy. It allows for the rapid confirmation of a diagnosis at the bedside, resulting in faster therapeutic interventions (e.g., pericardiocentesis). It usually results in greater patient satisfaction because of fewer attempts being required to successfully complete the procedure. ED ultrasonography can truly be a lifesaving modality when used by trained Emergency Physicians.
ACKNOWLEDGMENTS The authors would like to thank Linda J. Kesselring, MS, ELS, for copyediting the manuscript and incorporating our revisions into the final document; and Angela Taylor for manuscript preparation.
FIGURE 4-7. Needle shadow artifact (arrow) showing the hypoechoic vertical line originating from the needle tip.
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5
Trauma Ultrasound: The FAST Exam Wes Zeger
INTRODUCTION Evaluation of blunt trauma patients with ultrasound (US) has been described for over 30 years.1,2 Its use in the United States in the early assessment of blunt abdominal trauma patients rapidly increased in the 1990s.1 It is currently taught as an adjunct to the secondary survey in the Advanced Trauma Life Support (ATLS) course.1,3 US evaluation of the trauma patients decreases the time to operative care, resource utilization, and the costs of blunt trauma patients.4,5 The focused assessment with sonography in trauma exam, also known as the FAST exam, can be completed within 5 minutes.1 It has essentially replaced the need for a diagnostic peritoneal lavage in the initial assessment of all but a few trauma patients.6,7 This chapter reviews the technique and interpretation of the FAST exam.
ANATOMY AND PATHOPHYSIOLOGY The FAST exam evaluates four anatomical areas or potential spaces for the presence or absence of intraperitoneal fluid. These include the hepatorenal recess (Morrison’s pouch), the splenorenal recess, the rectovesical or rectouterine space, and the pericardial space. The assumption is that fluid represents blood in the setting of trauma. The presence of ascites, urine, and bowel fluid can appear similar. These spaces represent the most dependent areas in the supine patient (Figure 5-1). The volume of fluid accumulation required for visualization by US ranges from 250 to 620 mL.8,9 More experienced sonographers are able to visualize volumes closer to 250 mL.8
BLUNT THORACOABDOMINAL TRAUMA The most studied use of the FAST exam has been in adult patients with blunt abdominal trauma. The early diagnosis of hemoperitoneum and/or hemopericardium in the setting of blunt trauma is critical in the management of these patients. The sensitivity and specificity for the presence of hemoperitoneum varies depending on the comparison “gold standard,” and is generally reported between 78% to 90% and 98% to 100%, respectively.7,10–14 It has been reported to approach 100% sensitivity and 100% specificity in hypotensive patients.6,10 One study by Miller et al. reported a sensitivity of 42% and a specificity of 98%.15 The difference between these studies was how CT was utilized as the gold standard. Pediatric blunt trauma patients have been less well studied, but the FAST exam has shown a similar sensitivity and specificity.16–19 When used to predict the need for operative intervention in pediatric trauma patients, its sensitivity approached 90%, but its specificity dropped.20 Current guidelines recommend evaluation of the pericardial space in patients with blunt thoracoabdominal trauma.21
PENETRATING THORACOABDOMINAL TRAUMA Decreased mortality using US in the assessment of trauma was first described in relation to penetrating chest trauma.22 Its application in patients with penetrating abdominal trauma is less clear. The sensitivity ranges from 48% to 100%, but its specificity remains high at 98% to 100%.13,14,23,24 Assessment of the pericardial space can be helpful in guiding operative intervention in the unstable patient.
CONTRAINDICATIONS US is a noninvasive diagnostic modality. In the setting of trauma, it is contraindicated only if it would delay and negatively impact a clinically obvious need for emergent operative intervention. The FAST exam should not be performed unsupervised by providers who have not been adequately trained.21
INDICATIONS The FAST exam is performed after the primary survey. It can be performed in conjunction with ongoing resuscitative efforts. It is indicated when evaluating for the presence of intraperitoneal or pericardial blood in the setting of acute thoracoabdominal trauma. It is useful in determining resource allocation in the setting of multipatient trauma scenarios.1
A
EQUIPMENT • • • •
US machine US gel Abdominal US probe US probe cover or glove
B
FIGURE 5-1. The posterior reflection of the peritoneum is where blood initially layers in the supine patient. The hepatorenal (A) and splenorenal (B) recesses represent the posterior peritoneal reflections between the inferior pole of the kidney and the liver or spleen, respectively.
CHAPTER 5: Trauma Ultrasound: The FAST Exam
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A complete discussion of US equipment is beyond the scope of this chapter. Decisions regarding machines and probes depend on the user, cost, and intended applications. The FAST exam can be performed with a good-quality general abdominal probe. Probes with smaller footprints allow for easier viewing between the ribs. The US probe is generally used directly against the patient’s skin, with gel between them. Place the probe in a probe cover or glove to prevent contamination of the probe if the patient’s skin is covered with blood, urine, feces, or other substances. Place US gel in the probe cover or glove before inserting the probe. Squeeze out any air in the space between the tip of the probe and the probe cover or glove.
PATIENT PREPARATION Little to no preparation is required to perform the FAST exam. Wipe any debris and liquids from the patient’s skin in the areas to be scanned. Place the US probe in a probe cover or glove, as described above, if the patient’s skin is contaminated with blood, vomit, other body fluids, or other substances that may contaminate or damage the probe.
A
TECHNIQUE Performance of any US exam assumes the probe marker orientation is generally cephalad or toward the right relative to the patient. The FAST exam traditionally demonstrates two-dimensional grayscale images of four views reflective of their anatomic potential spaces. These are the hepatorenal recess (Morrison’s pouch), the splenorenal recess, the rectovesical or rectouterine space, and the pericardial space. View the rectovesicle space, the area between the rectum and the bladder, in the male patient. View the rectouterine space, the area between the rectum and the uterus, in the female patient. The overall exam time should be less than 5 minutes, and frequently can be completed in 1 or 2 minutes. If complete views of either the liver or spleen are not visualized with a single image, more than one image of the area is required. The order of image acquisition depends on the mechanism of injury. In blunt trauma, Morrison’s pouch is generally imaged first (the area where fluid will most likely first accumulate), followed by the splenorenal view, the rectovesical or rectouterine view, and then the pericardial space. In penetrating trauma, the pericardial space is often imaged first followed by Morrison’s pouch, then the remaining two views.
HEPATORENAL RECESS (MORRISON’S POUCH) The hepatorenal recess is located between the inferior margin of the liver and inferior pole of the right kidney (Figure 5-1A). Place the probe on the midaxillary line at the level of the 8th to 11th ribs (Figure 5-2A). The liver and kidney should be visualized from the diaphragm to the inferior tip of the liver (Figure 5-2B). It is important to visualize the space between, and including, the inferior liver tip and the inferior pole of the right kidney as fluid tends to accumulate near the tip of the liver first. A black, echolucent, stripe between the liver and the kidney represents blood and a positive FAST exam (Figure 5-3). Rib shadows obscuring portions of the image may be prevented by a slight counter-clockwise rotation of the probe so it lies between the ribs.
SPLENORENAL RECESS The splenorenal recess is located between the inferior margin of the spleen and the inferior pole of the left kidney (Figure 5-1B). Place the probe on the posterior axillary line at the level of the sixth to ninth ribs (Figure 5-4). The spleen and kidney should be visualized from the diaphragm to the inferior tip of the spleen. A black, echolucent, stripe between the spleen and the kidney represents
B FIGURE 5-2. Imaging of the hepatorenal recess. A. US probe placement with the corresponding US screen image. B. A view of the US beam (green) as it passes through the liver and kidney with the corresponding US image.
blood and a positive FAST exam (Figure 5-5). Rib shadows obscuring portions of the image may be prevented by a slight clockwise rotation of the probe so it lies between the ribs.
RECTOVESICAL OR RECTOUTERINE SPACE The rectovesical or rectouterine space represents the most inferior– posterior reflection of the peritoneum. Place the probe just superior to the pubic ramus (Figure 5-6). The probe can be oriented in either the sagittal or transverse plane. View the rectovesicle space (Figures 5-6A & B) or the rectouterine space (Figures 5-6C & D) in both the sagittal and transverse planes. A black, echolucent, stripe in either space represents blood and a positive FAST exam (Figures 5-7 & 5-8).
PERICARDIAL SPACE In the supine trauma patient, fluid accumulates initially in the inferior–posterior portion of the pericardial space. The probe and
30
A
SECTION 1: Introductory Chapters
B
FIGURE 5-3. A positive FAST exam of the hepatorenal recess. A. An echolucent fluid stripe in Morrison’s pouch. B. A normal exam for comparison.
A
B
FIGURE 5-4. Imaging of the splenorenal recess. A. US probe placement with the corresponding US screen image. B. View of the US beam (green) as it passes through the spleen and kidney.
A
B
FIGURE 5-5. A positive FAST exam of the splenorenal recess. A. An echolucent fluid stripe. B. A normal exam for comparison.
CHAPTER 5: Trauma Ultrasound: The FAST Exam
A
B
C
FIGURE 5-6. Imaging of the rectovesical and the rectouterine spaces. A. Transverse US probe placement for the rectovesical view with the corresponding US image. B. Sagittal view, and probe orientation, of the rectovesical space displaying the US beam path (pink) and the corresponding US image. C. Transverse view of the rectouterine space. D. Sagittal view of the rectouterine space.
A
D
B
FIGURE 5-7. A positive FAST exam of the rectovesical space. A. Transverse view of an echolucent fluid area. B. A normal exam for comparison.
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A
B
C
D
FIGURE 5-8. A positive FAST exam of the rectouterine space. A. Sagittal view of an echolucent fluid area. B. A normal sagittal exam for comparison. C. A transverse view of an echolucent fluid area. D. A normal transverse exam for comparison.
screen image orientation are different than traditional echocardiographic views. Place the probe with the marker oriented toward the patient’s right and the tip of the probe aimed toward the patient’s left shoulder (Figure 5-9). Use the liver as an acoustic window and
increase the depth of the US beam to increase image quality. Fluid will initially accumulate near the top of the US image, representing the inferior portion of the pericardial space (Figure 5-9 inset). Visualize both the inferior and superior areas of the pericardial space. A black, echolucent, stripe in either the inferior or superior areas of the pericardial space represents blood and a positive FAST exam (Figure 5-10).
ALTERNATIVE TECHNIQUES
FIGURE 5-9. Imaging of the pericardial space. US probe placement for the subxyphoid view with the corresponding US image. (RV, right ventricle; RA, right atrium; LV, left ventricle; LA, left atrium).
The incorporation of thoracic imaging coupled with the traditional FAST exam has been referred to as an extended FAST or EFAST exam. This additional imaging assesses for the presence of a hemothorax or a pneumothorax. A hemothorax is best assessed by visualizing the inferior–posterior aspect of the plural cavity in the supine patient (Figure 5-11). This area is often visualized in routine views of Morrison’s pouch, but moving the US probe superior one rib interspace may be required. The lung edges are not normally visualized on US. However, the lung can be seen “floating” in fluid in the presence of a hemothorax (Figure 5-11B). Another sign suggestive of a hemothorax is the “spine” sign (Figure 5-11B). In the presence of a hemothorax, the portion of the thoracic spine above the diaphragm can be visualized with US. The thoracic spine is not normally well visualized on US superior to the diaphragm (Figure 5-11C). A pneumothorax is best assessed in the supine patient with either a linear or a curvilinear probe. Place the probe on the anterior chest wall in the area bounded by the clavicle, sternum, nipple, and anterior
CHAPTER 5: Trauma Ultrasound: The FAST Exam
33
A
A
B FIGURE 5-10. A positive FAST exam of the pericardial space. A. A large echolucent area of fluid in the inferior–posterior aspect of the pericardial space and a small amount of fluid in the more superior area of the pericardial space. B. A normal exam for comparison.
axillary line. Start with the probe on the midclavicular line between the nipple and the clavicle. It may be moved within the area to obtain the best image possible. Position the probe perpendicular to two adjacent ribs to visualize the intercostal space (Figure 5-12). The normal sliding of the visceral pleura against the parietal pleura during respiration can be visualized (Figure 5-12A). This interface between the two pleura is known as the “sliding-lung” sign and is absent in a pneumothorax. Use M-Mode to visualize the “sea-shore” sign (Figure 5-12B). This is visualized as slightly wavy parallel lines from the thoracic wall over an echogenic line (the pleural line), under which is a sandy pattern produced by the lung parenchyma. The parallel lines at the top of the screen represent the waves of the “sea.” The sandy pattern at the bottom of the screen represents the “shore.” Together they form the “sea-shore” sign. The echogenic line between the “sea” and the “shore” represents the pleural lines. The “sea-shore” sign indicates a normal chest wall–lung interface. Air interposed between the chest wall and lung forms parallel, horizontal echogenic lines and the loss of the “sea-shore” sign (Figure 5-12C).
ASSESSMENT The interpretation of each of the four views, and of the overall FAST exam, is classified into one of the three categories: positive, negative, or indeterminate. Positive exams demonstrate echolucent
B
C FIGURE 5-11. Imaging a hemothorax. A. The patient and US probe position. The US beam path (green) generates the pleural component (inset). B. Blood in the pleural space provides an acoustic window to visualize the thoracic spine (“spine sign”). C. A normal exam for comparison.
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SECTION 1: Introductory Chapters
B
A
FIGURE 5-12. Imaging a pneumothorax. A. Rib shadowing is seen on both sides of the intercostal space. The echoic interface of the parietal and visceral pleura demonstrates the “sliding-lung” sign. B. The “sea-shore” sign. It is visible when the lung and chest wall are in contact with each other. Note the bright echogenic stripe of the pleural interface between the chest wall (“sea”) and the lung (“shore”). C. The “sea-shore” sign and the pleural interface are absent when a pneumothorax is present.
(seen as black on the image) fluid accumulations in any one of the four views. Negative exams and scans demonstrate no fluid with complete visualization of all structures of each view. Indeterminate exams are uncommon but may occur when fat or bowel cannot be distinguished from peritoneal fluid, or if there is incomplete visualization of any of the four views. Women and children may normally have a small amount of physiologic fluid in their pelvis. This finding may lead to an indeterminate exam in the setting of trauma.
AFTERCARE Multiple algorithms exist for the management of trauma patients.1,3 In general, these are differentiated into blunt trauma versus penetrating trauma and hemodynamically stable versus unstable. In the hemodynamically stable blunt trauma patient, a positive FAST exam is typically followed with an abdominal cat exam. In the hemodynamically unstable adult blunt trauma patient, a positive FAST exam indicates the need for emergent operative intervention without further imaging. In adult patients with penetrating trauma, a positive FAST exam has good correlation with need for a therapeutic laparotomy.23 Management of these patients may vary between institutions. An unstable pediatric patient with a positive FAST exam may not necessarily proceed to laparotomy as the indications for operative management differ between adults and children.3 A negative FAST exam needs to be evaluated within the patient’s clinical context (history, exam findings, vitals, etc.). In the
C
hemodynamically stable or unstable penetrating trauma patient, a negative FAST exam is a reliable screen for the presence of intrapericardial blood. It is not a reliable screening test for the presence of abdominal injury. In the unstable patient, its use is not well defined. In the hemodynamically stable blunt trauma patient, a negative FAST exam should be followed by serial clinical exams and a repeat FAST exam.25 A negative FAST exam in the presence of hemodynamic instability has a high sensitivity, and an extraperitoneal source of bleeding or the instability should be considered. Indeterminate FAST exams require a follow-up alternative diagnostic modality, usually a CAT exam.
COMPLICATIONS Performance of the actual FAST exam has no associated complications. However, inaccurate interpretation or inappropriate application of US findings in clinical decision making may complicate its use.
SUMMARY The FAST exam is a useful adjunct in the management of blunt and penetrating trauma patients. It can be performed rapidly, it is very specific, and it can positively impact patient outcomes. Proper training is required to ensure good-quality images and appropriate interpretation.
SECTION
Respiratory Procedures
6
Essential Anatomy of the Airway Ned F. Nasr, Serge G. Tyler, Gennadiy Voronov, and Isam F. Nasr
INTRODUCTION A thorough understanding of anatomy is essential for the performance of any medical procedure.1–10 Untoward events due to a procedure are usually the result of inexperience and/or an inadequate understanding of the regional anatomy. The anatomy of the airway and airway procedures are no exception. From the evaluation of external anatomic landmarks to the performance of nerve blocks for fiberoptic intubation, an understanding of the anatomy of the airway will result in fewer attempts at intubation and improved success with fewer iatrogenic misadventures.
GENERAL ANATOMY The upper airway comprises the nasal and oral cavities, the pharynx, and the larynx. The lower airway consists of the subglottic larynx, the trachea, and the bronchi.8 Airway management typically involves the upper airway, the focus of this chapter. The anatomy of the pharynx, larynx, and trachea are depicted in Figure 6-1. The nares serves as the functional beginning of the airway, namely warming and humidification of air.4 The mucosa of the nasal passage is extremely vascular and fragile and therefore susceptible to trauma. The nasal blood supply originates from branches of the internal and external carotid arteries. It is wise to consider the use of a vasoconstricting agent, when appropriate, to help avoid epistaxis which may obscure further attempts at securing the airway. Although patients tolerate nasal intubation better than oral intubation for a longer period of time, it is more important in an emergency to definitively secure the airway using a straightforward oral intubation if possible. The sensory innervation of the upper airway is provided by branches of several cranial nerves. The mucous membrane of the nose is innervated anteriorly by the anterior ethmoid nerve (ophthalmic division of the trigeminal nerve) and posteriorly by the sphenopalatine nerve (maxillary division of the trigeminal nerve). The tongue is innervated by the lingual nerve on its anterior twothirds (a branch of the facial nerve) and by the glossopharyngeal nerve posteriorly. The glossopharyngeal nerve also innervates the adjacent areas, including the palatine tonsils, the undersurface of the soft palate, and the roof of the pharynx.1 The anatomy of the oropharynx is discussed further under the “Airway Evaluation” section and the anatomy of the larynx is covered in the next section. The trachea measures 10 to 16.5 cm in an average adult.4 The trachea is a tubular structure that begins at the level of the fifth or sixth cervical vertebrae and bifurcates at the level of the fifth thoracic vertebra into two primary bronchi. The posterior aspect of the trachea is flat and membranous, while its anterior and lateral aspect is
2
lined by 16 to 20 horseshoe-shaped cartilaginous rings. The primary bronchi subsequently branch into three secondary bronchi on the right and two secondary bronchi on the left. The angle between the primary bronchus and the trachea on the left is more acute than on the right. This is due to the heart being located on the left side. This is clinically significant during aspiration and endobronchial intubations. Because of the more direct path on the right side due to the obtuse angle of the primary bronchi, objects (food, fluid, and foreign bodies) are more likely to enter the right lung. The tracheal mucosa removes waste products by producing and moving mucus toward the pharynx via ciliary action. The trachea has a rich innervation from the vagus nerve, which permits a vigorous cough reflex (accompanied by hypertension and tachycardia) if a foreign body is aspirated. The inner diameter of the trachea varies between normal adult males and females. It ranges from about 15 to 20 mm.4 Since the external diameter of a 7.5 mm internal diameter (ID) endotracheal tube is 11.0 mm, the size must be taken into consideration in selecting an endotracheal tube. These considerations usually preclude using tubes much larger than 7.5 mm ID for normal adult females or larger than 8.0 or 8.5 mm ID for normal adult males.
ANATOMY OF THE LARYNX The innervation of the larynx is relatively simple. The internal branch of the superior laryngeal nerve provides sensation above the vocal cords (vocal folds). The recurrent laryngeal nerve supplies sensation below the vocal cords. The recurrent laryngeal nerve provides the motor input to all of the intrinsic muscles of the larynx except to the cricothyroid muscle, which is supplied by the external branch of the superior laryngeal nerve. Bilateral injury to the recurrent laryngeal nerve will result in total airway closure due to unopposed stimulation of the vocal cord adductor, the cricothyroid muscle.1 There are three paired and three unpaired cartilages of the larynx.2 The paired cartilages are the smaller arytenoid, corniculate, and cuneiform cartilages (Figure 6-2). The unpaired cartilages are the larger thyroid, cricoid, and epiglottic cartilages. Although not part of the larynx, the hyoid bone has many ligamentous and muscular attachments to the larynx. The cricoid cartilage is signet ring-shaped, as opposed to the C-shaped cartilages of the trachea (Figure 6-2). Because it forms a complete circle, depression of the cricoid cartilage will put pressure on structures located posteriorly (i.e., the esophagus). The application of posteriorly directed pressure on the cricoid cartilage during intubation is known as the Sellick maneuver (Figure 6-3). The Sellick maneuver will not prevent regurgitation from active vomiting. It has been shown to be effective in the prevention of passive regurgitation and subsequent aspiration.3 However, the Sellick maneuver can impair insertion of the laryngoscope or an airway introducer, and can cause airway obstruction. The cricoid cartilage is also an important landmark for locating the cricothyroid membrane, which lies inferior to the thyroid cartilage and superior to the cricoid cartilage (Figure 6-2). The 35
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Nasal concha
Vestibule of nose
Nasopharynx
Hard palate Oral cavity
Soft palate Uvula of soft palate Oropharynx
Tongue
Palatine tonsil
Mandible Hyoid bone
Epiglottis Vocal fold Larynx
Thyroid cartilage
Cricoid cartilage
Esophagus
Trachea
FIGURE 6-1. Anatomy of the airway as visualized in a midsagittal section through the head and neck.
cricothyroid membrane is usually located at the level of the sixth cervical vertebra. It is the anatomic location where emergency cricothyroidotomies and recurrent laryngeal nerve blocks are performed. The three paired cartilages are located on the posterior aspect of the larynx (Figure 6-2). This position renders them vulnerable to injury during intubation.2 By maintaining an anterior insertion of the laryngoscope blade and by not inserting it too deeply during intubation attempts, it is less likely that these cartilages will become dislocated or otherwise injured. This is particularly true if a straight laryngoscope blade is used. The hyoid bone is an important supporting structure of the upper airway. One of the attachments of the hyoid bone to the larynx is the hyoepiglottic ligament located at the base of the vallecula (Figure 6-4). This ligament is important because it is where the tip of the curved Macintosh laryngoscope blade is placed to
move the epiglottis anteriorly and out of the path of vision during intubation. Another attachment of the hyoid bone to the larynx is the thyrohyoid membrane (Figure 6-2). As its name implies, it runs from the inferior border of the hyoid bone to the superior aspect of the thyroid cartilage. Just inferior to the lateral border of the hyoid bone, the internal branch of the superior laryngeal nerve passes through the thyrohyoid membrane (Figure 6-2). At this point, the internal branch of the superior laryngeal nerve is superficial and very easily anesthetized with an injection of local anesthetic solution.
AIRWAY EVALUATION The evaluation of the airway should always start with a thorough history. An airway history should be conducted, when feasible, prior to the initiation of airway management in all patients. It
CHAPTER 6: Essential Anatomy of the Airway
37
Epiglottis Hyoid bone
Entry point of internal branch of superior laryngeal nerve Thyrohyoid membrane Cuneiform cartilage Arytenoid cartilage Thyroid cartilage Cricothyroid muscle Cricothyroid cartilage
Trachea Anterior view
Posterior view
FIGURE 6-2. Right anterolateral and posterior views of the skeleton of the larynx. The thyroid cartilage shields the smaller cartilages of the larynx.
should include whether the patient has ever required intubation and if there was any difficulty. Additional history should focus on the patient’s dentition and any surgery on or near the airway. There are many congenital syndromes (Table 6-1) and acquired conditions (Table 6-2) that can complicate airway management. These should be kept in mind when performing the airway history and physical examination.
External evaluation of the airway is a critical step to a successful intubation. These brief evaluations are helpful in predicting a difficult intubation. External inspection should identify some obvious problems that may interfere with airway management. These include as facial hair which prevents a good mask seal, cervical collars which restrict neck movement, face and/or neck trauma, severe micrognathia, or obesity. The next steps in evaluating the airway may help to identify patients with potentially difficult airways. In adults, the distance between the thyroid cartilage (“Adam’s apple”) and the inside of the
Vallecula (location of hyoepiglottic ligament)
Epiglottis
Tubercle of epiglottis
Vocal fold
Aryepiglottic fold
FIGURE 6-3. The Sellick maneuver. Posteriorly directed pressure is applied to the cricoid cartilage to occlude the esophagus and prevent regurgitation and subsequent aspiration of gastric contents.
Trachea
Corniculate cartilage
FIGURE 6-4. Laryngoscopic view of the larynx.
Cuneiform cartilage
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TABLE 6-1 Selected Congenital Syndromes Associated with Difficult Endotracheal Intubation Syndrome Description Down’s Cervical spine spondylolisthesis; large tongue, small mouth make laryngoscopy difficult; small subglottic diameter possible; frequent laryngospasm Goldenhar Mandibular hypoplasia and cervical spine (oculoauriculovertebral abnormality make laryngoscopy difficult anomalies) Klippel–Feil Neck rigidity because of cervical vertebral fusion Pierre Robin Small mouth, large tongue, mandibular anomaly; awake intubation essential in neonate Treacher Collins Laryngoscopy difficult (mandibulofacial dysostosis) Turner High likelihood of difficult intubation Source: Data from Barash et al.1
anterior aspect of the mandible is known as the thyromental distance. It should be at least 5 cm or about three large finger breadths.1 A lesser distance suggests that the patient’s vocal cords are positioned more anteriorly than normal. Distances less than 5 cm may indicate that visualization of the larynx during intubation may be difficult or impossible due to a lack of space in which to displace the tongue. The next evaluation requires the patient to open his or her mouth maximally. Ideally, the patient will be in a seated or semisitting position. The distance between the maxillary and mandibular incisors in an average adult is 3 to 5 cm or about two large finger breadths.5 Limited mouth opening may impair visualization of the airway as well as expose the teeth to damage during intubation. Adults should be able to flex their cervical spine 35° and extend the cervical spine (atlantooccipital joint) 80° from a neutral position.6 This range of neck movement allows for the alignment of the oral, pharyngeal, and laryngeal axes during orotracheal intubation (Figure 6-5). This alignment of the axes provides the greatest chance for a successful intubation. Recent evidence suggests that slight head extension in infants and young children by placing a rolled towel behind their shoulders better aligns the vision of the glottic and laryngeal axes.10 Observe the patient’s neck for length and thickness. A short, excessively long, or thick neck may indicate difficulty in placing the patient in the “sniffing position” and align the airway axes. The internal examination should evaluate the patient’s dentition, palate, and tongue. Note any protuberant incisors, loose teeth, broken teeth, dental work, and dental devices. Prominent upper incisors may complicate the insertion of the laryngoscope blade, make laryngoscopy difficult, and predispose the patient to dental trauma. Assess the relation of the maxillary and mandibular incisors during normal jaw closure. Lack of an overbite forces the laryngoscope blade to enter the mouth in a more cephalad direction than normal. This can result in difficulty visualizing the airway. Observe the maxillary and mandibular incisors during voluntary protrusion of the mandible to determine the degree of temporomandibular joint mobility. Determine if the palate is normal, high and arched, or cleft. Determine if the tongue is elevated, larger, or wider than normal in comparison to the oral cavity. Any abnormality can make the procedure of orotracheal intubation more difficult. A common classification used by Anesthesiologists to grade the difficulty of laryngoscopy and intubation involves the identification of the size of the tongue in relation to the tonsillar pillars, the fauces, the soft palate, and the uvula.7 It is important to perform this evaluation by first instructing patients to open their mouths and protrude their tongues maximally in the sitting position. The patient
TABLE 6-2 Acquired Conditions Affecting the Airway and Associated with Difficult Endotracheal Intubation Principal pathologic clinical Condition features of the airway Acromegaly Acute burns Angioedema Arthritis Rheumatoid arthritis Ankylosing spondylitis Benign tumors Cystic, hygroma, lipoma, adenoma Diabetes mellitus Foreign body Hypothyroidism Infectious Supraglottitis Croup Abscess (intraoral, retropharyngeal) Ludwig’s angina Malignant tumors Carcinoma of tongue, larynx, or thyroid Morbid obesity Pregnancy Sarcoidosis Scleroderma Temporomandibular joint syndrome Thyromegaly Trauma Head, face, or cervical spine injury
Macroglossia; prognathism Edema of airway (worsens with time, secure airway early!) Obstructive swelling renders ventilation and intubation difficult Temporomandibular joint ankylosis, cricoarytenoid arthritis, deviation of larynx, restricted mobility of cervical spine Ankylosis of cervical spine; less commonly ankylosis of temporomandibular joints; lack of mobility of cervical spine Stenosis or distortion of airway May have reduced mobility of atlantooccipital joint Airway obstruction Large tongue, abnormal soft tissue (myxedema) make ventilation and intubation difficult Laryngeal edema Laryngeal edema Distortion and stenosis of airway and trismus Distortion and stenosis of airway and trismus Stenosis or distortion of airway; fixation of larynx or adjacent tissues secondary to infiltration or fibrosis from irradiation Short, thick neck, and large tongue are likely to be present Edema of airway Airway obstruction (lymphoid tissue) Tight skin and temporomandibular joint involvement make mouth opening difficult Severe impairment of mouth opening Goiter may produce extrinsic airway compression or deviation Cerebrospinal rhinorrhea, edema of airway; hemorrhage; unstable fracture(s) of maxillae and mandible; intralaryngeal damage; dislocation of cervical vertebrae
Source: Modified from Miller.4
should not say “ahhh,” as this distorts the anatomy and may falsely improve the airway classification. The Mallampati classification, named after its author, has four grades or classes.7 The anterior and posterior tonsillar pillars, the fauces, the soft palate, and the uvula can be fully visualized in class I (Figure 6-6A). The fauces, the soft palate, and the uvula can be visualized in class II (Figure 6-6B). The anterior and posterior tonsillar pillars are covered by the base of the tongue and not visible. Only the soft palate and the base of the uvula are visible in class III (Figure 6-6C). None of the structures are visible in class IV (Figure 6-6D). The predictive value of this classification is that during direct laryngoscopy, the entire glottis can be exposed in 100% of class I airways, 65% of class II airways, 30% of class III airways, and 0.1% of class IV airways.7 The airway evaluation is imperfect in predicting potential problems and an airway strategy (combination of plans) should be drawn up for each patient. Additional evaluation may be indicated in some
CHAPTER 6: Essential Anatomy of the Airway
39
FIGURE 6-6. The Mallampati classification. A. Class I. B. Class II. C. Class III. D. Class IV.
patients to characterize the likelihood or nature of the anticipated airway difficulty. The findings of the airway history and physical examination may be useful in guiding the selection of specific diagnostic tests and consultation.
ANATOMIC DIFFERENCES BETWEEN THE ADULT AND THE YOUNG CHILD
FIGURE 6-5. Schematic diagram demonstrating head positioning for endotracheal intubation. A. The normal alignment of the oral, pharyngeal, and laryngeal axes. B. Elevation of the head about 10 cm with pads below the occiput, while the shoulders remain on the table, aligns the laryngeal and pharyngeal axes. C. Subsequent head extension, at the atlantooccipital joint, serves to create the shortest distance and most nearly a straight line from the incisor teeth to glottic opening.
There are numerous differences between the airway of an adult and that of a child. The head-to-body ratio is larger in the child. This causes the neck to be flexed when the child is supine. Placing a rolled towel under the child’s shoulders will correct the flexion. A child has a small mouth with a relatively large tongue as compared to an adult. This can make orotracheal intubation difficult. The presence of adenoidal tissue in the child makes nasotracheal intubation difficult and orotracheal intubation the preferred method. The anatomic differences between the larynx of an adult and that of a young child are summarized in Table 6-3 and Figure 6-7.1 The vocal cords are more obliquely inclined in the child. The cricothyroid membrane is very small and narrow. The most important difference is that the narrowest portion of the infant or young child’s airway is below the level of the vocal cords at the level of the cricoid cartilage. In an adult, the narrowest point of the airway is at the level of the vocal cords. The cricoid cartilage is the only complete cartilaginous ring and the narrowest part of the trachea. An endotracheal tube may therefore pass through the vocal cords of a young child but might not advance past the cricoid cartilage due to normal anatomy. Forcing an endotracheal tube past the vocal cords in a young child may result in trauma to the airway and subsequent tracheal stenosis. Because the child’s larynx is located more cephalad at the level of the third or fourth cervical vertebrae and
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TABLE 6-3 Anatomic Differences Between the Child’s and the Adult’s Larynx Child’s larynx Adult’s larynx Size Smaller Larger Shape Lumen is funnel shaped with the Narrowest part of narrowest part below the vocal cords lumen is at the and within the cricoid ring vocal cords Location Higher, closer to the tongue base; Vertical extent is vertical extent is opposite C3, C4, C5 lower, opposite C4, vertebrae; more anterior C5, C6 vertebrae Epiglottis Longer, narrower, and “U” shaped; the Shorter and wider angle between glottis and epiglottis is more acute; increased chance of airway obstruction (see Figure 6-7) Vocal cords Angled in relation to the axis of trachea; Perpendicular to shorter; more cartilaginous; more the axis of trachea distensible; more likely to be injured Rigidity The laryngeal cartilages are softer and More rigid more pliable Response Mucous membrane is more loosely Less vulnerable to trauma attached and swells more readily when to trauma and traumatized or infected infection
lead to more effective ventilation. The child’s diaphragm is shorter and flatter than the adult, and thus has a decreased excursion during respiration. The child’s relatively narrower airways result in an increased resistance to inspiratory and expiratory airflow. They are also more susceptible to airway edema and mucous plugs obstructing their narrow airway. Children have smaller and fewer alveoli. This results in less surface area for gas exchange compared to adults.
SUMMARY It is essential for Emergency Physicians to know the anatomy of the airway, especially the differences found in the young child. The airway assessment is an essential element in the preparation to intubate a patient. Unfortunately, there may be limited information and time available to perform the full assessment in an emergent setting. Performing the airway assessment in every patient before orotracheal intubation will allow one to perform it quickly in an emergency.
7 angulated anterior to the glottis, blind nasal intubation in the case of airway emergencies is not possible. The child’s laryngeal inlet is narrow and more susceptible to obstruction. The U-shaped epiglottis and a more acute angle between the epiglottis and glottis cause the aryepiglottic folds to be more in the midline (Figure 6-7B). Differences also exist in the trachea. Children have a relatively shorter trachea. This makes both right main bronchial intubation and accidental extubation much easier. The narrower diameter of the trachea with smaller spaces between the cartilaginous rings makes a tracheostomy more difficult to perform. To avoid injury and subsequent subglottic stenosis, uncuffed endotracheal tubes should be used in children less than 28 days of age.11 A correctly sized endotracheal tube should have a leak at 15 to 25 cm water. Using the uncuffed endotracheal tube with high leak pressure more than 25 cm of H2O or the cuffed endotracheal tube can not only cause croup after extubation, but also create an erosion of the mucosa and subglottic stenosis. A cuffed endotracheal tube is recommended for anyone above the age of 28 days.10–13 The differences also continue into the chest. The infant thoracic cage is more compliant than the older child and adult. This can
A Epiglottis
B
Vocal fold
Aryepiglottic fold FIGURE 6-7. Differences between the adult’s larynx (A) and the child’s larynx (B).
Basic Airway Management Christopher J. Russo and Zach Kassutto
INTRODUCTION Airway management is one of the most basic and important aspects of Emergency Medicine. The concepts and techniques described in this chapter can be applied in a variety of environments. Understanding the following concepts and having an opportunity to practice them will allow one to provide the most fundamental of all medical care, support of a patient’s airway. Airway management remains crucial. Without oxygen, the brain begins to die within minutes.1 The primary purpose of airway management is to facilitate the transport of oxygen to the lungs. The secondary purpose is to protect the airway from contamination with blood, fluids, or food. Airway management can be as simple as lifting a snoring patient’s chin or as involved as awake, fiberopticguided endotracheal intubation. The fundamental importance of airway management is reflected by the fact that two-thirds of basic life support taught by the American Heart Association is concerned with this vital function.2 The mission of airway management is to ensure a patent airway, provide supplemental oxygen, and institute positive-pressure ventilation when spontaneous breathing is inadequate or absent.3 These three key aspects of airway management warrant repeating. Ensure a patent airway. Provide supplemental oxygen. Provide positive-pressure ventilation. Time is always critical when a patient needs airway support. The body’s limited oxygen stores are rapidly exhausted once breathing stops. A healthy individual having maximally breathed 100% oxygen will begin to desaturate and have brain injury after 5 minutes of apnea. However, a sick patient breathing room air will desaturate almost immediately upon becoming apneic.1 Oxygenation and ventilation remain the essential goals of airway management. Inadequate ventilation may occur for a variety of reasons. Spontaneously breathing patients may develop an airway obstruction due to food, blood, secretions, or tissue obstruction from the loss of normal pharyngeal tone. The conscious patient with airway obstruction will be in obvious distress and is more likely to have obstruction due to a foreign body, tissue swelling from an infection, laryngeal edema, tumor, or laryngospasm. The unconscious patient,
CHAPTER 7: Basic Airway Management
despite spontaneous respiration, is at risk for aspiration of gastric contents. Unconscious patients should have their airway secured as well as receive mechanical ventilation.
ANATOMY AND PATHOPHYSIOLOGY The “upper airway” includes the nasal, oral, pharyngeal, and laryngeal anatomy and physiology. This highly complex system is responsible for conveying warmed and filtered air to the trachea and lungs while simultaneously allowing for passage of liquids and solids to the esophagus. Phonation is a secondary physiologic function of the larynx.4 This highly sophisticated system allows us to drink liquid, eat food, breathe, and talk simultaneously. However, if a small drop of liquid or a particle of food enters the airway, a profound system of reflexes is activated to protect its integrity.5 The nasal cavity and the nasopharynx is the area from the tip of the nose to the palate. The nasal cavity is bounded laterally by the bony framework of turbinates and medially by the nasal septum. This area is highly innervated by the ophthalmic and maxillary branches of the trigeminal nerve. The mucosa of the nasal cavity and the nasopharynx is highly vascular. It is this high degree of vascularity that allows cool air from the environment to be warmed and humidified prior to entering the lungs. It also dictates that care be taken when nasal airways are placed. It takes very little trauma to the nasal mucosa to cause significant epistaxis. Polyps or mucus can obstruct the nasopharynx, as can congestion due to an upper respiratory infection. The nasopharynx is oriented in an anteroposterior plane. In the supine patient, nasal airways or nasogastric tubes should always be passed perpendicular to the horizontal axis and not in a cephalad direction. The oropharynx extends from the palatoglossal fold down to the epiglottis. The primary structure contained within the oropharynx is the base of the tongue. The anterior two-thirds of the tongue is innervated by the lingual nerve, a branch of the facial nerve. The posterior one-third of the tongue, the tonsils, and the palate are innervated by the glossopharyngeal nerve.6 Salivary glands located in the oropharynx can produce a significant volume of saliva, creating potential problems for mask ventilation or intubation. Loose teeth can be inadvertently dislodged into the oropharynx, becoming potentially hazardous foreign bodies in the airway. Edentulous patients present a unique set of problems for mask ventilation.7 The lack of a maxillary alveolar ridge allows the face mask to collapse into the airway. Redundant tissue, due to lack of teeth, tends to collapse into the airway as well, making mask ventilation without an oral or a nasal airway extremely difficult. An appropriately sized and placed oral airway is the best way to overcome the problem of upper airway obstruction in the unconscious and edentulous adult patient. The laryngopharynx extends from the epiglottis to the inferior border of the cricoid cartilage. The piriform recesses lie in the pharynx, on either side of the larynx, and the esophagus resides posteriorly. The larynx is positioned at the entrance to the trachea, acts as the sphincter of the pulmonary system, and is made up of nine cartilages to support this function.6 There are three paired and three unpaired cartilages. The unpaired cartilages are the epiglottis, the thyroid cartilage, and the cricoid cartilage. The paired cartilages are the arytenoids, the corniculates, and the cuneiforms. The cricoid cartilage is the only complete ring in the entire airway. This presents a unique opportunity for the practitioner to help prevent gastric aspiration. The cricoid cartilage can be firmly pressed posteriorly to pinch the esophagus against the cervical spine and prevent the passive regurgitation of gastric contents. This is known as the Sellick maneuver.8 The cricoid cartilage is the narrowest point of the airway in the pediatric patient while the glottic narrowing is the most narrow point in adults. The cricoid and thyroid cartilages are
41
TABLE 7-1 Indicators that Warrant Respiratory Assistance SaO2 < 90% PaO2 < 60 mmHg on 40% O2 Respiratory rate > 35 PaCO2 > 55 mmHg Vital capacity < 15 mL/kg A-a gradient > 350 mmHg on 100% O2 Source: Data from Shapiro et al.10
the landmarks for identifying the cricothyroid membrane, which is essential in obtaining an emergent surgical airway. The sensory and motor innervation of the larynx is derived from the vagus nerve.6 The superior laryngeal nerve is a branch of the vagus nerve and gives rise to the internal branch, which provides the sensory innervation of the upper larynx. The superior laryngeal nerve also gives rise to the external branch, which provides the motor innervation to the cricothyroid muscle (a vocal cord adductor). The recurrent laryngeal nerve provides the sensory innervation to the larynx below the vocal cords and motor innervation to all other laryngeal muscles.6 The trachea is approximately 15 cm long in an adult. It is composed of 17 or 18 C-shaped cartilaginous rings.6 The rings are essential to prevent the trachea from collapsing during the negative intrathoracic pressures generated on inspiration.
INDICATIONS The decision to institute airway support must often be made very quickly and frequently without the aid of laboratory results, radiographic studies, or pulmonary function tests. The decision to institute emergent airway support is usually based on clinical judgment and the signs and symptoms of inadequate oxygenation and ventilation. The signs of impending respiratory failure are tachypnea, dyspnea, cyanosis, agitation, and the use of accessory muscles.9 In the case of a partial airway obstruction, the patient will demonstrate extreme anxiety, audible wheezing or stridor, as well as aggressive attempts to clear the obstruction. If the obstruction is complete, there may be no audible breath sounds at all. If time permits, a more formal evaluation of the indicators that warrant respiratory assistance should be performed (Table 7-1). The ultimate signs indicating the necessity for airway assistance are hypoxia and hypercarbia. The most common etiologies resulting in the need for airway support are cardiopulmonary arrest, drug overdoses, toxic reactions, and airway obstruction (food, vomit, or foreign body). Impending ventilatory failure due to congestive heart failure, severe asthma, or pneumonia are also common indications for endotracheal intubation.
CONTRAINDICATIONS There are no absolute contraindications for basic airway management. The contraindications for the various methods of endotracheal intubation are discussed in subsequent chapters.
EQUIPMENT • • • • • •
Bag-valve-mask device Oxygen source Clear face masks, various sizes and shapes Oropharyngeal airways, various sizes Nasopharyngeal airways, various sizes Head strap
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• • • • •
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Yankauer suction catheter Suction source Pulse oximeter Tongue blades or tongue depressors Water-soluble lubricant or anesthetic jelly
TECHNIQUES PATIENT POSITIONING The first goal of airway management, regardless of a patient’s ability to breathe spontaneously, is the establishment of a patent airway. This may be all that is required in a patient who has an upper airway foreign body or a patient who has suffered a loss of consciousness with loss of pharyngeal tone. The importance of proper positioning cannot be overemphasized. The success of airway management is predicated on this very basic but often overlooked issue. Placing the patient in the “sniffing” position, or lateral decubitus position, may correct many upper airway obstructions due to soft tissue impingement.11 The “sniffing” position is achieved by flexing the cervical spine approximately 15° and extending the atlantooccipital joint maximally (Figure 7-1). This is the position one subconsciously adopts in order to sniff and smell. Head extension in this manner must be omitted in the patient for whom cervical spine precautions are in effect. This position can also be achieved with the chin-lift and/or jaw-thrust maneuvers. If the patient is obese or has large breasts, they often cannot be effectively managed in a supine position. The normal sniffing position in an obese person is often not sufficient to relieve an airway obstruction (Figure 7-2A). Place a ramp or shoulder roll under the patient’s upper back to achieve the sniffing position (Figure 7-2B).
JAW-THRUST MANEUVER The jaw thrust is one of the most basic maneuvers and an initial method of establishing a patent airway.12 The tongue is attached to the mandible and falls into the pharynx in the supine patient. The goal of the jaw-thrust maneuver is to move the tongue away from the palate and posterior pharyngeal wall. The jaw-thrust maneuver is a two-handed technique that can also be used with the face mask and a second person to provide positive-pressure ventilation. The operator is positioned at the head of the patient and places their
FIGURE 7-1. The “sniffing” position for successful airway management.
FIGURE 7-2. Airway management in the obese patient. A. The normal “sniffing” position is inadequate to open the airway. The dotted line represents the axis of the airway. B. A ramp placed under the head and shoulders will achieve the “sniffing” position.
fingers on the angles of the patient’s mandible bilaterally, then displaces the mandible anteriorly (Figure 7-3). This maneuver elevates the tongue from the pharynx and allows air to flow unobstructed and posterior to the tongue.
CHIN-LIFT MANEUVER The chin lift is also one of the most basic maneuvers and an initial method of establishing a patent airway.12 The chin lift is performed by the operator placing their fingers on the inferior surface of the patient’s mandible (Figure 7-4). Do not place any of the fingers on
FIGURE 7-3. The jaw-thrust maneuver.
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FIGURE 7-6. Insertion of the nasopharyngeal airway. FIGURE 7-4. The chin-lift maneuver.
the soft tissues of the submandibular space, as this will elevate the tongue and cause further obstruction. Lift the chin in an anterior and cephalic direction. The head may also be tilted slightly posterior to aid in opening the airway.
NASOPHARYNGEAL AIRWAYS The majority of airway obstructions occurs in the region of the pharynx.13 In addition to proper positioning, one can use various aids to overcome this site of obstruction and facilitate effective ventilation. The most commonly used devices are oropharyngeal (oral) and nasopharyngeal (nasal) airways. Regardless which device is chosen, it is important to place a large enough airway to bridge the area of soft tissue impingement on the pharynx. Nasal airways are soft rubber or plastic tubes that are inserted through the nostril and into the oropharynx, just above the epiglottis. Nasal airways are available in numerous sizes (Figure 7-5). The proximal end has an enlarged flange that rests against the patient’s nares and prevents the nasal airway from slipping backward into the nose and becoming a foreign body in the patient’s airway. The larger the inner diameter, the longer the tube. Once positioned, the
nasal airway is more comfortable for the patient than an oral airway, but nasal airways carry the significant risk that their placement may result in epistaxis.3,10 A size 30 or 32 French nasal airway is appropriate for most adults. It can be safely placed in the conscious, semiconscious, or unconscious patient, and can also be used when an oral airway cannot be placed (e.g., oral trauma, braces, seizures, trismus, etc.). It is imperative to also perform the jaw thrust and/or chin lift to prevent the tongue from obstructing the patient’s airway when using a nasal airway. Insertion of a nasal airway is a rapid procedure. Choose the proper size nasal airway by placing the flared end of the airway near the tip of the patient’s nose. The distal end of the nasal airway should be at the external auditory canal. Liberally apply a water-soluble lubricant or an anesthetic jelly to the nasal airway. If not contraindicated, apply a vasoconstrictor to the patient’s nasal mucosa. Gently insert and advance the nasal airway with the beveled tip against the nasal septum (Figure 7-6). This will prevent any epistaxis from the tip of the nasal airway getting caught on the inferior or middle turbinate. Also insert it along the floor of the nasal cavity adjacent to the septum. Continue to advance the nasal airway completely until the flared end is against the patient’s nostril. Rotate the nasal airway 90° so it is concave upward. If resistance is encountered during insertion, slight rotation will often facilitate the passage of the nasal airway. If resistance is still encountered, insert the nasal airway into the other nostril or use a smaller nasal airway. Supplementary oxygen or positive-pressure ventilation with a bag-valve-mask device can be started after insertion of the nasal airway. Insertion of a nasal airway may be associated with complications. If the device is too long, it may cause laryngospasm and vomiting. It may also be placed with its tip in the esophagus, resulting in gastric distention and subsequent aspiration. Nasal mucosal injury upon insertion can result in epistaxis and aspiration of blood.
OROPHARYNGEAL AIRWAYS
FIGURE 7-5. Nasopharyngeal airways.
The oropharyngeal (oral) airway is a semicircular plastic device that holds the tongue up and away from the posterior pharyngeal wall (Figure 7-7). Oral airways cause less trauma and are more easily placed than nasal airways. Oral airways must be used only in unconscious patients. They may result in laryngospasm and vomiting if placed in a conscious or semiconscious patient.14 An 8.0, 9.0, or 10.0 cm oral airway is appropriate for most adults. Oral airways have many uses. The primary indication is to maintain a patent airway. It will prevent the patient from biting,
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SECTION 2: Respiratory Procedures
A
FIGURE 7-7. Oropharyngeal airways.
occluding, and lacerating an endotracheal tube. It facilitates oropharyngeal suctioning by removing the tongue from the airway, and will also protect the tongue from bites during seizure activity. Insertion of the oral airway is a quick and simple procedure. Choose the proper size oral airway. The correct size is estimated by placing the proximal flange of the oral airway next to the patient’s mouth. The distal tip should lie just above the angle of the mandible. Clear the mouth and oropharynx of any blood, secretions, or vomit with a Yankauer suction catheter. Open the patient’s jaw with the nondominant hand. Separate the patient’s jaws with a “scissors-like” action of the thumb on the lower teeth and the index or middle finger on the upper teeth. Insert the oral airway curved side down (Figure 7-8A). The tip will slide along the hard palate. Insert it until the plastic flange on the proximal end is at the patient’s lips. Rotate it 180° so that the curve of the oral airway follows the curvature of the tongue. An alternative method is to use a tongue blade to depress the tongue and then insert the oral airway as described above. If the tongue blade is used, the oral airway may also be inserted with the curve side upward (Figure 7-8B). Supplementary oxygen or positive-pressure ventilation with a bag-valve-mask device can be started after the insertion of the oral airway. Insertion of an oral airway is not a benign procedure. If the oral airway is not inserted properly, it can push the tongue posteriorly and further obstruct the oropharynx. Significant lacerations can occur if the lips or tongue are caught between the teeth and the oral airway. If the oral airway is too long, it can force the epiglottis closed against the vocal cords and produce a complete airway obstruction. Too small of an oral airway will force the tongue against the pharynx and produce an obstruction.
MASK VENTILATION The likelihood of success in airway management is often predictable, given enough time to fully assess a patient’s history and anatomy (please refer to Chapter 6).15 The ease of mask ventilation and intubation is directly related to anatomy. Anesthesiologists rely on a series of evaluations and classification criteria to help predict the success of airway management. The most widely used classification is the Mallampati classification (Figure 6-6).16 This evaluation— coupled with an examination of the patient’s body habitus, thickness of the patient’s neck, temporomandibular joint function, ability to fully open the mouth, dental structures, cervical range of motion, and thyromental distance—can help predict the ease or difficulty of airway management.15–21
B FIGURE 7-8. Insertion of the oropharyngeal airway. A. It is inserted with the curve toward the tongue. After insertion, it is rotated 180°. B. It is inserted with the curve toward the palate. A tongue blade is used to depress the tongue and facilitate insertion.
A distinction must be made between ease of mask ventilation and ease of oral endotracheal intubation. The two are often correlated but can, at times, be completely unrelated. For example, a patient with a normal body habitus who is in a cervical halo may be very easy to ventilate by mask but impossible to intubate orally via direct laryngoscopy. Conversely, the patient who is obese, suffers from sleep apnea, but has a Mallampati class 1 airway may be very easy to intubate but virtually impossible to ventilate by mask. After achieving the proper positioning, the presence of spontaneous respirations must be evaluated. If the patient is not breathing and there is no evidence of a foreign body, positive-pressure ventilation must be initiated. In the awake patient with complete airway obstruction due to a foreign body, the Heimlich maneuver is the method of choice.2 If the patient has become unconscious and the foreign body is clearly visible, remove it. However, caution must be used to prevent forcing the object further into the airway. Instrument removal of airway foreign bodies with a McGill forceps is possible if the foreign body is visible and within reach of the forceps. Once the airway is patent, the options for positive-pressure ventilation include mouth-to-mouth, mouth-to-mask, and bag-valve devices (mask ventilation). The remainder of this section will review the latter, as the other two options are not used in Emergency Departments or hospitals. The key to effective mask ventilation is ensuring a continually patent airway. This is initially achieved by placing the patient in the sniffing position, coupled with
CHAPTER 7: Basic Airway Management
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FIGURE 7-10. The two-handed, two-person mask ventilation technique. FIGURE 7-9. The one-handed, one-person mask ventilation technique.
THE NUMASK™ a combination of chin lift and jaw thrust. Neglect of this key maneuver leads to an excessive use of positive-pressure ventilation in an attempt to compensate for an obstructed upper airway. Improper patient positioning associated with positive-pressure ventilation will force gas into the stomach, increasing intraabdominal pressure and resulting in the need for ever-increasing positive pressure on the airway. Rising intraabdominal pressure will eventually make ventilation difficult or impossible, and significantly increase the risk of gastric aspiration. When called upon to mask ventilate a patient, always keep in mind the importance of proper positioning and the use of an appropriately sized oral or nasal airway as an adjunct. Face masks should be made of clear plastic and/or silicone, have a soft seal, and have an anatomic shape that conforms to the contours of the patient’s face. Typical adult sizes are 3, 4, and 5. The mask must be large enough to completely cover the nose, mouth, and chin but not so large as to allow a leak. It should not cover any part of the patient’s eyes. There are two ways to properly hold a face mask. The one-handed technique is performed with the nondominant hand (Figure 7-9). The operator should be positioned at the top of the bed looking down at the patient’s head. Place the little, ring, and middle fingers under the patient’s mandible. Place the index finger and thumb on the bottom and top portions of the mask. This technique allows the operator to simultaneously lift the mandible and extend the atlantooccipital joint while applying enough downward pressure on the face mask to create an airtight seal. An elastic head strap is a very helpful device to aid in sealing the mask tightly. The dominant hand is used to ventilate the patient through the bag-valve device. A two-handed technique may be necessary in patients with facial hair and those who are obese, elderly, or edentulous. Two people are required to perform this technique, in which both of the operator’s hands are applied to the face mask to aid in the creation of a tight seal and align the airway properly (Figure 7-10). Place the face mask on the patient’s face. Place the index, middle, ring, and small fingers of the left hand on the body of the left side of the patient’s mandible. Position the right hand similarly on the right side of the patient’s mandible. Apply both thumbs to the mask and apply pressure to create a seal. Anteriorly elevate the mandible to perform the jaw-thrust maneuver. This is the two-person technique and makes it necessary to have an assistant apply positive pressure through the bag-valve device attached to the face mask. It is preferable, whenever possible, to use the two-person technique which allows for improved bag-valve-mask ventilation.25
A relatively new device can be used to assist in ventilation instead of a traditional face mask. The NuMask (NuMask Inc., Woodland Hills, CA) solves the problem of having to create an airtight face mask seal in patients. This device is an intraoral mask for teenagers and adults that connects to a bag-valve device and eliminates the need for a face mask (Figure 7-11A). It is especially useful in patients whom it is difficult to get a good face mask seal (e.g., obese, facial hair, and facial trauma) or for the one-person bagging technique. The company makes a retention shield that wraps around the patient’s head to secure the device and seal the patient’s nostrils. This allows for easy one-person bagging. The NuMask is simple to insert into the patient’s mouth. Place the device into the patient’s mouth. It should sit between the patient’s teeth/gums and the cheeks/lips (Figure 7-11B). Use the thumb and index finger of the nondominant hand to pinch the patient’s nostrils closed (Figures 7-11C & D). Use the hand and remaining fingers to wrap around the external tube portion and to seal the patient’s lips over the intraoral portion of the device (Figures 7-11C & D). The moisture in the patient’s oral cavity maintains the airtight seal. Attach the bag-valve device and begin ventilations. If ventilation is difficult, remove the NuMask , insert an oral airway, replace the NuMask , and begin ventilations. There are numerous advantages of using the NuMask over the traditional face mask. It is ideal for operators with small hands who have difficulty grasping and maintaining a seal with a face mask. While initially cumbersome to use, it is easier to maintain a seal than a face mask. Ventilation is easier when only one person is available to bag and ventilate the patient. It can be used in patients in whom a good face mask seal is difficult. The device can be used in both conscious and unconscious patients as it should not cause a gag reflex. Finally, the one size available will fit most teenagers and adults. A pediatric version is not available.
™
™
™
™
™
THE BAG-VALVE DEVICE A bag-valve device is used to provide positive-pressure ventilation. It consists of a self-inflating bag connected to oxygen on one end and a one-way (nonrebreathing) valve on the other. They are available in several sizes depending on the age of the patient (Figure 7-12). The valve end is connected to the face mask, or other airway device, to allow one-way flow of oxygen. The other end has tubing to attach the bag to an oxygen source. This device can also force air into the esophagus and stomach and place the patient at risk for aspiration if not used properly.
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A
FIGURE 7-11. The NUMASK™ intraoral mask. A. The device. B. The device is inserted between the patient’s teeth/gums and their lips/cheeks. C. Proper hand positioning to seal the patient’s nostrils and lips. D. An alternative hand positioning.
It may be difficult to provide adequate ventilatory volumes through the bag-valve device attached to a face mask. This is often due to an inadequate seal of the face mask on the patient while maintaining an open airway. It can also result from inadequate squeezing
of the bag to generate an appropriate volume of air flow. Consider using the two-person technique to resolve these issues. If ventilation is difficult in a child, change the face mask from the standard teardrop shaped mask to a circular-shaped face mask. Stand above the patient’s head. Place the patient in the sniffing position. Apply a face mask. Attach the bag-valve device to the face mask and begin positive-pressure ventilation. Begin ventilations at a rate of 10 to 12 per minute, or squeeze the bag every 5 to 6 seconds. If ventilation is difficult, apply the jaw-thrust and/or chin-lift maneuvers. If ventilation is still difficult, insert an oral or nasal airway. If ventilation is still difficult, the patient requires an invasive airway device immediately. The American Society of Anesthesiologists has published an algorithm to facilitate decision making in the face of airway management problems. A detailed discussion of the various intubation options is presented in following chapters.
PEDIATRIC CONSIDERATIONS
FIGURE 7-12. The bag-valve-mask device. From left to right: adult size, child size, and infant size.
Significant differences exist between the adult and pediatric airway as described in Chapter 6. The ratio of head-to-body size is greater in infants and young children. Care must be taken to achieve proper positioning for optimal airway angulation. A towel may be placed under an infant’s shoulders, while younger children may be optimally positioned while lying flat on the stretcher. Older children may require a towel under the head to achieve ideal positioning.23 Despite proper head positioning, loss of tone in the muscles
47
CHAPTER 8: Pharmacologic Adjuncts to Intubation
supporting and protecting the upper airway may still result in an airway obstruction. This may be corrected by the use of a jaw thrust, chin lift, nasal airway, or oral airway. Infants and children have a higher minute ventilation and cardiac output than adults, as well as higher basal oxygen consumption. They also have a lower functional residual capacity which leads to oxygen desaturation more rapidly than in adults when apnea occurs. When oxygenation and ventilation are provided in an effective and efficient fashion, hypoxic bradycardia can be prevented or reversed.23 Properly sized equipment remains crucial to the success of airway management, and can be addressed by the use of the Broselow tape. It should be noted that there is insufficient evidence for or against the routine use of laryngeal mask airways during pediatric cardiac arrest. While an acceptable adjunct in the hands of experienced providers, it is associated with a higher incidence of complications in young children.24
the use of several pharmacologic adjuncts (Tables 8-1 & 8-2). This includes a potent anesthetic agent to induce unconsciousness and a neuromuscular blocking agent to produce paralysis.
COMPLICATIONS
INDUCTION AGENTS
The most serious complication of basic airway management is aspiration of gastric contents. The aspiration of acidic gastric contents can result in an acute chemical pneumonitis. This phenomenon is known as the Mendelson syndrome and has an associated 50% mortality.22 It is a significant risk when airway management is needed emergently or routinely in the pregnant, trauma, diabetic, or obese patient. Less serious complications include soft tissue trauma to the lips, tongue, oral cavity, and eyelids. Tooth fractures or avulsions are uncommon but possible. A dermatitis or allergic reaction to the plastic material is rarely seen. Facial nerve dysfunction due to pressure effects of the mask are transient. Corneal abrasions, conjunctival chemosis, and increased intraocular pressure are common with masks that are too large.
The ideal induction agent has an extremely rapid onset of action, produces predictable deep anesthesia, has a short duration of action, and has no adverse effects.2 Unfortunately, such an agent does not yet exist. However, there are at least six drugs that can safely be used for induction of anesthesia and intubation. These include thiopental, methohexital, etomidate, ketamine, and propofol. Midazolam and fentanyl may also be used alone or in conjunction with the above agents.2 The decision as to which induction agent is the most suitable is largely dependent on the Emergency Physician’s experience and his or her understanding of each drug’s properties. In this section, each of these drugs is briefly detailed as to its pharmacokinetics, mechanism of action, pharmacodynamics, administration, and adverse effects.
TABLE 8-1 Recommended Anesthetic Doses of Pharmacologic Agents Used for Rapid Sequence Induction Adult dose Pediatric Onset Medication (mg/kg) dose (mg/kg) (sec) Thiopental 2–5 2–6 24 h after major burns and trauma, crush injury, denervation, prolonged immobilization, paraplegia, hemiplegia, muscular dystrophy) and malignant hyperthermia. Elevates intraocular, intracranial, and intragastric pressures. Use the total body weight (not the lean weight) even in the morbidly obese or pregnant patient. An alternative to succinylcholine provided that there is no anticipated difficulty in intubation.4 Cardiovascular effects unlikely. Alternative to succinylcholine. Stereoisomer of atracurium. No cardiovascular effects. Organ-independent elimination. Elimination independent of liver and kidney. Releases histamine. Tachycardia and sympathetic nervous system activation.
CHAPTER 10: Rapid Sequence Induction TABLE 10-5 Pharmacology of the Anesthetic Induction Agents Steady-state volume Agent Dose (mg/kg) of distribution (L/kg) 2.5 Thiopental Adults: 3.0–5.0 Children: 3.0–5.0 Infants: 7.0–8.018 Etomidate 0.2–0.3 2.5–4.5 Propofol Adults: 1.5–2.5 2.0–10.0 Children: 3.0–6.0 Midazolam 0.1–0.2 1.0–1.5 Ketamine 1.0–2.0 2.5–3.3 Methohexital 1.0–3.0 0.4 Fentanyl 0.002–0.02 4.0
Clearance (mL/min/kg) 3.4
Elimination half-life (h) 11.6
10.0–20.0 59.4
2.0–5.0 4.0–7.0
7.5 16.0–18.0 6.56 4.8–10.5
1.0–4.0 1.0–2.0 22 days 3.5–4.0
63
Source: Adapted from References 3, 7, 8, and 18.
port. Attach the laryngoscope blade to the handle and make sure that the light is functional. Simultaneously, the nurses should apply a noninvasive blood pressure cuff, continuous pulse oximetry, and cardiac monitoring to the patient. They should also draw up and label the required medications, establish intravenous access, set up the suction, record all events, and continuously observe the noninvasive blood pressure readings, cardiac monitor, and pulse oximeter. If there is no suspicion of a cervical spine injury, position the patient in the optimum “sniffing” position. If there is suspicion of a cervical spine injury, an assistant should provide manual inline axial stabilization of the head and neck during the intubation sequence and remove the anterior aspect of the cervical spine collar to allow for maximal mouth opening and access to the neck. Premedicate the patient (Table 10-3). The mnemonic “LOAD” has been used to indicate the pretreatment drugs for RSI.15 The mnemonic stands for lidocaine, opioid (specifically, fentanyl), atropine, and defasciculation. Lidocaine (1.0 to 1.5 mg/kg) can be given to blunt the intracranial pressure response, transient hypertension, bronchospasm, and tachycardia associated with intubation. Fentanyl (2 to 3 µg/kg) or one of its derivatives can be given to also blunt the intracranial pressure response, transient hypertension, and tachycardia associated with intubation. Atropine (0.01 to 0.02 mg/kg, minimum 0.1 mg, maximum 1.0 mg) should be given to children less than 1 year old to prevent bradycardia in response to direct laryngoscopy. Administer a defasciculating dose of a nondepolarizing neuromuscular blocking agent. This is onetenth of the intubating dose (Table 10-4). Phenylephrine (50 µg) can be given to attenuate the hypotensive response to intubation. Administer an appropriate induction agent as indicated by the clinical setting and patient’s hemodynamic status (Tables 10-5 and 10-6). Flush the intravenous line with 5 to 10 mL of 0.9% normal saline solution after each drug to ensure delivery. Administer a neuromuscular blocking agent.1,2,5 Numerous agents are available (Table 10-4). The most commonly used medications are
succinylcholine (1.0 to 1.5 mg/kg) or rocuronium (1.0 to 1.2 mg/kg). Succinylcholine is the preferred agent. Its effects are short lasting (4 to 6 minutes). This is especially useful if the patient cannot be intubated, as they will need to be ventilated with a bag-valve-mask device until the succinylcholine wears off. Rocuronium allows the same intubating conditions as succinylcholine except that it lasts for 30 to 60 minutes. This is problematic if the patient cannot be intubated. An assistant should apply cricoid pressure as soon as the patient loses consciousness and maintain it until successful oral endotracheal intubation has been confirmed. Avoid mask ventilation if possible. If hypoxemia or hypercarbia ensues, begin mask ventilation to a maximum pressure of 20 cmH2O while maintaining cricoid pressure. Intubate the trachea 60 to 90 seconds after the succinylcholine (or rocuronium) has been administered and the patient’s muscles are relaxed, as noted by apnea and jaw relation. Confirm the correct position of the endotracheal tube by visualizing the tube passing through the vocal cords, observing sustained presence of end-tidal CO2 on the capnograph, and auscultating breath sounds at the midaxillary lines.11,12 Auscultate over the epigastric area to ensure that ventilation is not audible over the stomach. Release cricoid pressure. If indicated, administer a long-acting paralytic agent (Table 10-4). After successful intubation, administer additional sedative hypnotics and analgesics as dictated by clinical needs. Obtain a chest radiograph to confirm proper placement of the endotracheal tube.
SPECIAL CONSIDERATIONS IN PEDIATRIC PATIENTS Rapid sequence induction is often used in the Emergency Department for securing the airway of pediatric patients. The indications and equipment, except for being smaller, are essentially not different than in the adult patient. Infants and young children have
TABLE 10-6 Cardiovascular and Central Nervous System Effects of Anesthetic Induction Agents Cerebral Agent Blood pressure Cardiac contractility blood flow CMRO2
Intracranial pressure
Cerebral perfusion pressure
Thiopental Etomidate Propofol Midazolam Ketamine Methohexital Fentanyl
Decrease Decrease Decrease Decrease Increase Decrease Increase or no change
Decrease or no change Increase Decrease or no change No change Increase or no change Increase No change
Decrease Slight decrease or no change Decrease Slight decrease Increase Decrease Slight decrease
Source: Adapted from Chapter 8.
Decrease or no change No change Decrease No change Increase Decrease No change
Decrease Decrease Decrease Decrease Increase Decrease Decrease
Decrease Decrease Decrease Decrease Increase Decrease Decrease
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developmental differences in head and neck anatomy (Chapter 6). These differences make the Miller blade the preferred laryngoscope blade for intubation in this group. Infants and young children have a higher volume of distribution, which is why they require different doses of induction agents as reflected in Tables 10-4 & 10-5. Preoxygenation is particularly important for infants and children. Compared with adults, these young patients have a higher oxygen consumption rate and a lower functional residual capacity. Consequently, oxygen desaturation occurs much more rapidly. If the child is desaturating or apneic, careful bag-mask ventilation with small tidal volumes (while maintaining cricoid pressure) should be performed to achieve adequate preoxygenation. The use of succinylcholine remains controversial in pediatrics. Rapid sequence induction and laryngospasm are perhaps the last remaining indications for the use of succinylcholine in pediatrics. In 1994, the US Food and Drug Administration (FDA) recommended that the use of succinylcholine in children be reserved for emergency intubation and instances where the immediate securing of the airway is necessary due to the risks of hyperkalemia. This includes patients with laryngospasm, difficult airways, full stomachs, or for intramuscular use. If a child has no vascular access, succinylcholine (4 mg/kg) can be administered intramuscularly. It will provide a maximum onset of blockade in 3 to 4 minutes and last approximately 20 minutes. If there is a contraindication to using succinylcholine, rocuronium can be used for RSI. Children between 2 and 12 years old require more rocuronium than adults. The recommended doses are 0.9 to 1.2 mg/kg in this age group. Atropine is commonly used in young children. Atropine (20 µg/kg) administered as a premedication is indicated in all children 0.6 Fluid/serum protein > 0.5 Pleural fluid LDH > 200 IU/mL Pleural fluid LDH > 2/3 upper limit of normal for serum
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TABLE 40-4 Potential Complications Associated with a Thoracentesis Cough Hemothorax Hypovolemia Hypoxemia Inadequate yield Intrapleural infection Laceration of an intercostal nerve or vessel Laceration of the liver or spleen Pain at the procedure site Pneumothorax Reexpansion pulmonary edema Shortness of breath Tension pneumothorax Vasovagal reactions
The procedure site should be evaluated two to three times a day for signs of infection. These patients should be educated about the signs, symptoms, and significance of an infection. They should return to their primary physician or the Emergency Department immediately if they develop fever, chills, shortness of breath, redness or pus at the puncture site, or if any concerns arise.
COMPLICATIONS The potential complications of a thoracentesis are listed in Table 40-4.1,3,16,28,35 Complication rates range from 20% to 50%. The major complications are a 5% to 19% incidence of pneumothorax and a 1% to 7% incidence of pneumothorax requiring a chest tube.11,36 One author recommends ultrasound-guided thoracentesis for all patients as the safest approach, although this is disputed by others.9,36 The majority of studies report lower rates of postprocedural pneumothoraces with ultrasound-guided thoracentesis performed by an experienced operator.9–11,15,37–41 However, others have not shown a significant difference in the incidence of postprocedural pneumothoraces with the use of ultrasound.42,43 The use of the proper technique and the Emergency Physician’s experience are important in reducing the rate of complications.44–46 Despite this, it is difficult to predict which patients may be at risk of developing a postprocedural pneumothorax.47 Drainage of large volumes of fluid, greater than 1.5 to 2 L, may increase the risk of developing a pneumothorax.48 Improper technique or tortuosity of the intercostal artery can result in intercostal artery injury.49 Qureshi compiled methods to reduce the incidence of pneumothorax.16 They are direct supervision of inexperienced operators, removal of small amounts of fluid, use of small-gauge needles, use of ultrasound for small effusions, and use of a needle-catheter system for a therapeutic procedure.
PNEUMOTHORAX ANATOMY AND PATHOPHYSIOLOGY A thoracentesis can be performed to relieve a simple pneumothorax or a tension pneumothorax. A pneumothorax can be defined by the presence of air between the visceral and parietal pleura.25 Primary spontaneous pneumothoraces occur in otherwise healthy people without antecedent trauma. Secondary spontaneous pneumothoraces occur as a complication of underlying lung disease, most commonly chronic obstructive pulmonary disease.1,3 A traumatic pneumothorax occurs as a result of penetrating or blunt trauma to the thoracic cavity. An iatrogenic pneumothorax is a subcategory of the traumatic pneumothorax, with the three most
common etiologies being pleural biopsy, subclavian vein catheterization, and thoracentesis. The pressure in the pleural space is negative in reference to the atmosphere. This is due to the tendency of the lung to collapse and the chest wall to expand. The alveolar pressure is greater than the pleural space pressure due to the elastic recoil of the lung. As a result, if a communication occurs between the alveolar and pleural space, the air will preferentially move into the pleural space until the pressure equalizes. The physiologic consequence is a decrease in vital capacity and PaO2. This may be well tolerated in otherwise healthy people but not in patients with underlying cardiac and/or pulmonary disease. If a one-way valve develops such that air can only enter the pleural space from the alveolus but not return, the intrapleural pressure will eventually exceed atmospheric pressure, with a progressive increase in air occupying the pleural space. Clinical deterioration may occur due to a decreasing PaO2 and cardiac output.50–52 Other data point to hypoxia and hypercarbia as the cause of clinical deterioration.18 Ultrasound guidance may aid in locating a pneumothorax, with the best viewing window being the intercostal space. Zhang et al. showed a sensitivity and specificity of ultrasound in diagnosing a pneumothorax of 86% and 97%, respectively; whereas conventional radiography was 28% and 100%, respectively.53 In addition, ultrasound diagnosed a pneumothorax within only 2 to 5 minutes, compared to 20 to 30 minutes for chest radiography.53 In a similar study, ultrasound showed a sensitivity and specificity of 100% and 94% for detection of pneumothoraces, compared to 36% and 100% for chest radiography.54 Controversy exists to the exact management of a spontaneous pneumothorax.55–60 Options include simple aspiration, tube thoracostomy, and simple aspiration followed by a tube thoracostomy if aspiration fails. Simple aspiration is more likely to fail with larger pneumothoraces.58,59 Several recent reviews, including a Cochrane Collaboration, came to similar conclusions regarding simple aspiration.55–57 These conclusions, while not definitive, were that simple aspiration is associated with a reduction in the percentage of patients requiring hospitalization compared to tube thoracostomy. There were no differences between the two procedures in early failures, immediate success rate, duration of hospitalization, one-year success rates, and the number of patients requiring a subsequent pleurodesis. Advantages of simple aspiration compared to tube thoracostomy include less equipment costs, easier to perform, simpler to perform, quicker to perform, and the potential to avoid hospitalization.
INDICATIONS All tension pneumothoraces require needle drainage followed by tube thoracostomy. Patients usually present with respiratory distress, tachycardia, unilateral absence of breath sounds, hypotension, and neck vein engorgement. Although difficult to assess, these patients have tracheal deviation that is often limited to the thoracic cavity. Not all simple pneumothoraces require drainage, as they may resolve spontaneously. Conservative management has shown a spontaneous resorption rate of 1.25% per day.46 A pneumothorax should be drained if the patient complains of dyspnea, dyspnea on exertion, pain, or if the pneumothorax is estimated to be 15% or greater.
CONTRAINDICATIONS There are no absolute or relative contraindications to relieving a tension pneumothorax, as it is a life-threatening emergency. Contraindications to thoracentesis to relieve a simple pneumothorax are few. These include infection at the site of the procedure,
CHAPTER 40: Thoracentesis
259
in which case an alternate site should be selected.3 A traumatic pneumothorax or a pneumothorax associated with a hemothorax or pyothorax requires tube thoracostomy. Any pneumothorax that is expanding or expanding despite thoracentesis also requires a tube thoracostomy. Any patient on anticoagulation or with a suspected bleeding diathesis, whether known or suspected, may require reversal of the condition before the procedure.1 A patient with minimal symptoms and a small pneumothorax may be observed before deciding to evacuate the pneumothorax.
EQUIPMENT Pneumothorax—Tension • Alcohol swab, povidone iodine solution, or chlorhexidine solution • 12 to 16 gauge catheter-over-the-needle, 2 in. long Pneumothorax—Stable • Sterile gloves and gown • Face mask with a face shield or goggles • Povidone iodine or chlorhexidine solution • Sterile gauze sponge • Sterile towels • Sterile basin • Syringes for anesthesia infiltration, 5 and 10 mL • 25 gauge needle for anesthesia infiltration of the skin • 21 or 23 gauge needle for infiltration of subcutaneous tissue, periosteum, and pleura • 16 or 18 gauge catheter-over-the-needle • 14 to 18 gauge catheter-through-the-needle • Pigtail or straight catheter kit • Three-way stopcock • 50 mL syringe • Intravenous extension tubing • Heimlich valve Ultrasound Guidance • Ultrasound machine • 3.5 to 5.0 MHz phased-array ultrasound probe • Sterile ultrasound gel • Sterile ultrasound probe cover Commercial kits have been developed and are available to provide the equipment needed to perform a thoracentesis. These kits are disposable, single-patient use, and contain all the required equipment. They save time in that the equipment does not have to be found and set up. Disadvantages include potentially increased cost and limited equipment in the kit.18 Common kits include the Pharmaseal, distributed by Baxter (Jacksonville, TX); the Arrow Clark Thoracentesis Kit, distributed by Arrow (Reading, PA); and the Argyle Turkel Safety Thoracentesis Kit, distributed by Boston Scientific (Miami, FL).3 The TRU-CLOSE Thoracic Vent (UreSil, Skokie, IL) is an alternative device to the pigtail catheter and Heimlich valve combination. It is a one-piece unit that combines an intrapleural catheter and an external one-way antireflux valve that attaches to the chest wall by an adhesive pad. Its insertion is quicker, easier, and simpler than a traditional catheter. The low profile makes ambulation and outpatient management easier for the patient. These devices are rarely available in the Emergency Department.
FIGURE 40-14. Relief of a tension pneumothorax. The patient should be in the supine position, with the head of the bed elevated 30° if not contraindicated. The second intercostal space in the midclavicular line is the recommended site. For pleural effusions or a debilitated patient, the midaxillary line or posterior axillary line may be used at the level of the fourth or fifth intercostal space.
PATIENT PREPARATION Explain the procedure, its risks, and benefits to the patient and/ or their representative and have a consent form signed.1 Place the patient supine on the bed. Alternatively, the patient may be supine with the head of the bed elevated to 30° (Figure 40-14). Clean any dirt or debris from the skin. Identify the anatomic landmarks required to perform the procedure. Although not required, it is recommended to place the patient on the cardiac monitor, noninvasive blood pressure cuff, pulse oximetry, and supplemental oxygen. Apply povidone iodine or chlorhexidine solution to the skin surface and allow it to dry. Apply sterile drapes around the site of the procedure. Atropine should be at the bedside. It may be administered (1.0 mg subcutaneously or intramuscularly or 0.5 mg intravenously) to patients who develop symptomatic bradycardia during the procedure. The most common approach is the second intercostal space in the midclavicular line (Figure 40-14). An alternate site is the fourth or fifth intercostal space in the midaxillary line. The Emergency Physician should wear full personal protective equipment to protect themselves from contact with the patient’s blood and body fluids as well as protect the patient from infection.
TENSION PNEUMOTHORAX TECHNIQUE If the patient has a tension pneumothorax, thoracentesis is both a diagnostic and therapeutic procedure. A tension pneumothorax is a true life threat. Identify the needle insertion site by palpating the second intercostal space in the midclavicular line. If a tension pneumothorax is clinically evident, ultrasound guidance is not necessary prior to needle decompression and should not delay treatment. Insert the catheter-over-the-needle over the superior border of the third rib to avoid the neurovascular bundle, which is located on the inferior border of the second rib. Advance the catheterover-the-needle into the pleural space. If time permits, a 5 to 10 mL syringe without the plunger can be attached to the catheter-overthe-needle. The syringe barrel can be used as a handle to advance the catheter-over-the-needle.
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When the pleural cavity is entered, a release of pressure and a small “pop” may be felt. Stop advancing the needle. Securely hold the needle so it does not move. Advance the catheter until the hub is against the skin. Remove the needle. If the patient has a tension pneumothorax, a continuous rush of air will be heard or felt. Needle thoracentesis for a tension pneumothorax is a temporizing measure; therefore, a tube thoracostomy should be performed immediately after this life-saving procedure. Refer to Chapter 39 for complete details regarding this procedure.
SIMPLE PNEUMOTHORAX TECHNIQUES A primary spontaneous pneumothorax occupying over 15% of the hemithorax is the indication for simple aspiration via a thoracentesis.3 The same sterile preparation, location of fluid, positioning, anesthesia considerations, and ultrasound-guided technique apply to the evacuation of a simple pneumothorax as to a diagnostic thoracentesis. Spontaneous pneumothoraces used to be drained by tube thoracostomy. Simple aspiration may be just as effective as a tube thoracostomy.55–60 If a tube thoracostomy is required, a small bore straight or pigtail catheter can be just as effective to manage a spontaneous pneumothorax.61–65 While an initial study recommends using small bore tubes in patients with chest trauma, further clinical information is required before this becomes standard of care.66 The advantages of a small bore catheter include: less pain on insertion, decreased need for analgesics and sedation, and the potential to discharge the patient with outpatient management.
■ CATHETER-OVER-THE-NEEDLE TECHNIQUE Two types of catheters can be used to perform this procedure. They are the catheter-over-the-needle and the catheter-through-theneedle (Figures 40-5 & 40-6). The catheter-over-the-needle technique is most commonly used (Figure 40-5). Make a small “nick” in the skin with a #11 surgical blade at the needle insertion site. Attach a 14 to 18 gauge catheter-over-the-needle to a 10 mL syringe as a handle. Insert the catheter-over-the-needle into the nick and advance it, reproducing the original anesthetized tract (Figure 40-5A). Apply negative pressure to the syringe as the catheter-over-the-needle is advanced. Stop advancing the catheter-over-the-needle when air is aspirated. Angle the catheter-over-the-needle superiorly. Securely hold the syringe and needle so they do not move. Advance the catheter until the hub is against the skin. Withdraw the needle and syringe as a unit while the catheter remains within the pleural cavity (Figure 40-5B). When the needle is removed, quickly cover the catheter with a gloved finger. This will prevent ambient air from entering the pleural cavity. Attach intravenous catheter extension tubing to the hub of the catheter. Place a three-way stopcock attached to a 50 mL syringe onto the extension tubing. Hold the catheter hub against the skin securely. Aspirate air into the syringe and then advance the air into the room by adjusting the three-way stopcock. Air is then withdrawn manually. This process should be continued until resistance is felt. If no resistance is felt after 4 L of aspiration, it is presumed that expansion has not occurred and a continual leak of air exists from the lung into the pleural cavity; therefore a tube thoracostomy should be performed. After no more air is aspirated, close the stopcock and secure it to the chest wall. The success rate for the aspiration of a pneumothorax is 64%.67,68
■ CATHETER-THROUGH-THE-NEEDLE TECHNIQUE The second option utilizes the catheter-through-the-needle system (Figure 40-6), which is known as the Bardig Intracath system. It is not as popular as the catheter-over-the-needle systems. Place the needle on a tuberculin syringe. Insert the needle and
advance it through the anesthetized tissues (Figure 40-6A). A small “nick” in the skin with a #11 surgical blade will facilitate the needle entry. Apply negative pressure to the syringe as the needle is advanced along the anesthetized tract and into the pleural cavity (Figure 40-6A). Stop advancing the needle when air is aspirated. Securely hold the needle so it does not move. Remove the syringe and cover the needle hub with a gloved finger. This will prevent ambient air from entering the pleural cavity. Angle the needle slightly superiorly and advance the catheter through the needle (Figure 40-6B). Withdraw the needle, leaving the catheter within the pleural cavity (Figure 40-6C). Once the needle is removed, do not readvance the needle, as the catheter may shear off and fall into the pleural cavity. Place a three-way stopcock attached to a 50 mL syringe onto the hub of the catheter. Place the needle guard on the needle. Secure the catheter by taping it to the skin. Withdraw air as previously described.
■ SELDINGER TECHNIQUE Drainage can also be accomplished using a pigtail or straight catheter and the Seldinger technique (Figure 40-15). An alternative is to use a central venous catheter if a pigtail catheter is not available.18,19 Attach a 16 gauge, 2 in catheter-over-the-needle to a 5 or 10 mL syringe. Insert the catheter, as described above, aimed superiorly. Securely hold the needle and syringe so it does not move. Advance the catheter to the hub. Remove the needle and syringe. Quickly cover the catheter hub with a gloved finger. Insert the guidewire through the catheter (Figure 40-15A). Hold the guidewire securely to prevent it from falling completely into the pleural cavity. Remove the catheter over the guidewire, leaving the guidewire in place (Figure 40-15B). Extend the skin incision with a #11 scalpel blade by 3 to 5 mm to allow the catheter to enter into the pleural space without “crumpling” (Figure 40-15C). Advance the dilator over the guidewire and into the pleural cavity to dilate the tract (Figures 40-15C & D). A gentle twisting motion of the dilator as it is advanced will aid in its insertion into the pleural cavity (Figure 40-15D). Hold the guidewire securely. Remove the dilator while leaving the guidewire in place. Insert the catheter over the guidewire and into the pleural cavity (Figure 40-15E). Remove the guidewire and attach a three-way stopcock to the catheter. Aspirate the air as described previously.
■ DRAINAGE SYSTEMS Drainage systems for a pneumothorax vary in style but function with the same “one-way valve” principle. The simplest method is a flutter valve. It is best illustrated by the following noncommercial method. Cut a premoistened finger from a sterile glove. Tie the proximal end to the thoracentesis catheter with a silk suture and cut the distal end so that it is open to the air1 (Figure 40-16). This creates a flutter valve and allows air to escape with coughing or expiration and prevents air from reentering the pleural space on inspiration. A commercial kit often contains a Heimlich flutter valve1 (Figure 40-17). The arrow on the clear protective tube covering the Heimlich valve must point away from the patient. Suction is usually not needed. Stable patients can be sent home with this setup. This includes patients with a primary spontaneous pneumothorax and a small apical pneumothorax with initial reexpansion and good apposition of the lung with the lateral chest wall. Up to 30% of patients with a secondary pneumothorax can be treated on an ambulatory basis. Additional requirements include good residual lung function, normal oxygen saturation, and an air leak adequately treated by thoracentesis.35 A contraindication to using the flutter valve is a hemothorax. A closed underwater seal system is recommended in these cases. Refer to Chapter 39 for details regarding the use of a closed underwater seal system and the other indications for its use.
CHAPTER 40: Thoracentesis
261
FIGURE 40-15. The Seldinger technique for inserting a catheter to aspirate a pneumothorax. A catheter-over-the-needle has been placed into the pleural cavity and aimed superiorly. The needle has been removed while the catheter remains in the pleural cavity. A. A guidewire is inserted through the catheter. B. The catheter is removed while the guidewire remains in the pleural cavity. C. The skin incision is enlarged with a #11 scalpel blade. A dilator is placed over the guidewire. D. The dilator is advanced over the guidewire and into the pleural cavity. A gentle twisting motion will help guide the dilator through the tract. E. The dilator has been removed while the guidewire remains inside the pleural cavity. The catheter is advanced over the guidewire and into the pleural cavity. The guidewire is then removed while the catheter remains inside the pleural cavity.
■ ULTRASOUND-GUIDED TECHNIQUE FOR A PNEUMOTHORAX The same sterile preparation applies to ultrasound evaluation of a pneumothorax as for evaluation of a pleural effusion. However, a pneumothorax may be more readily identified with the patient positioned supine rather than upright. A 3.5 to 5.0 MHz phased-array probe is recommended for ultrasound-guided examination of the
pleural space.22 In general, the orientation of the probe follows the convention that the probe marker should correlate to the reference point in the left upper corner of the screen. The key ultrasound features of a pneumothorax include: absence of inspiration–expiration related “lung slide,” loss of “comet tail” artifact, and broadening of the pleural line to a thick band.24 In the case of a unilateral pneumothorax, the hemithorax suspected of
FIGURE 40-16. Use of a finger from a sterile glove as a one-way valve. Place the proximal end of the finger on the drainage system and cut the distal tip. It will act as a one-way valve.
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SECTION 3: Cardiothoracic Procedures
A
B FIGURE 40-17. The Heimlich valve.
having a pneumothorax should be compared to the unaffected side, with the unaffected side showing normal “lung slide,” “comet tail” artifact, and pleural line 3 cm, makes access difficult in patients who are not thin. The close proximity of the brachial plexus can result in significant injury if the needle penetrates it. The length of the catheter may be too short to reach the superior vena cava if placed in the left axillary vein.
FEMORAL VEIN CANNULATION Contraindications to femoral line placement include infection, venous thrombosis, or significant trauma to the ipsilateral lower extremity or groin area. Abdominal trauma may result in an interruption of the inferior vena cava, allowing any infused fluid or blood to flow into the abdomen rather than into the central circulation. During CPR, blood return below the diaphragm is reduced and a femoral catheter must end near the level of the diaphragm for medications to be most effective. Catheterization via the internal jugular vein or subclavian vein is usually easier if the purpose of central venous access is pulmonary artery catheterization or transvenous cardiac pacing. These procedures often require fluoroscopy when they are performed through the femoral vein. Central venous pressures measured through a femoral vein catheter may be inaccurate unless the patient is perfectly supine.
EQUIPMENT • • • • • • • • •
Sterile gloves and gown Face mask and cap Povidone iodine or chlorhexidine solution Sterile drapes or towels Local anesthetic solution 25 gauge needle 5 mL syringes “Finder” needle, usually 22 gauge for an adult 5 mL syringe with a nonlocking hub
• • • • • • • • • • •
315
Thin-walled introducer needle or catheter-over-the-needle Guidewire Gauze 4 × 4 squares Central venous line Dilator #11 scalpel blade Nylon or silk suture, 3-0 or 4-0 Sterile saline Needle driver Tape and catheter site dressing material Catheter clamp, if supplied with the kit
A variety of standard kits are commercially available (Figure 49-9). They contain all required equipment except local anesthetic solution and sterile gloves. The appropriate catheter should be chosen based on the patient’s needs. The optimal catheter lengths for patients of different ages are summarized in Table 49-3. Catheters with between one and four lumens are available. Multiple-lumen catheters are available in a variety of sizes and allow simultaneous venous pressure measurement, administration of numerous medications, and venous sampling without disconnecting the infusion apparatus. Disadvantages of multiple-lumen catheters over single-lumen catheters include smaller lumen sizes for a given catheter’s outside diameter, greater cost, and the need to maintain unused lumens to prevent them becoming thrombosed. There is probably no increased risk of infection in using triple-lumen versus single-lumen catheters.29–31 Some comparisons between these devices are summarized in Table 49-4. Percutaneous sheaths are intended primarily for the introduction of intravascular devices, such as pulmonary artery catheters and transvenous pacing wires. They are most often used in the Emergency Department as a large-bore line for the rapid resuscitation of hypotensive and hypovolemic patients. Sheaths are available in many sizes and configurations. Many models have an adjustable hemostasis valve that may be removed and a side port that allows infusion while the main lumen is being used for monitoring. The equipment required for subclavian vein cannulation is the same as that for internal jugular vein cannulation. Subclavian vein catheters must be slightly longer or inserted farther than internal jugular vein catheters. Left-sided catheters must be a few centimeters longer or inserted farther than right-sided catheters. The longer needle should be used for subclavian vein cannulation if the kit used has two different lengths of introducer needles.
PATIENT PREPARATION Explain the procedure, its risks, and its benefits to the patient and/ or their representative. Obtain an informed consent for the procedure unless it is being performed emergently. Place the patient in the Trendelenburg position if catheterization of the internal jugular vein is being attempted. Position the patient in at least 15° of Trendelenburg to prevent an air embolism. Slightly rotate the patient’s head toward the side opposite that to be cannulated. A large degree of head rotation has been show to increase the overlap between the internal jugular vein and carotid artery, theoretically increasing the risk of carotid artery puncture.32 The subclavian vein is fixed to the surrounding tissues and will neither collapse nor distend. Therefore, the Valsalva maneuver or the extreme Trendelenburg position is not necessary. Head rotation is neither necessary nor helpful. Slightly abduct the patient’s arm on the side to be cannulated. Avoid placing rolled towels between
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SECTION 4: Vascular Procedures
A
FIGURE 49-9. Equipment needed for central venous catheterization. A. A commercially available central venous line kit. B. Examples of different catheter types available. From left to right: single-lumen, double-lumen, triple-lumen, and introducer sheath (Cordis).
TABLE 49-3 Catheter Sizes, Types, and Characteristics Catheter size (French) Number of lumens 2 1
Patient size Infant
3
1
15 kg
7
1 (sheath), 2, 3
>40 kg
8 and larger
1 (sheath), 2, 3, 4
Adult
B
Venous access site Femoral, internal jugular, external jugular, or subclavian Femoral, internal jugular, external jugular, or subclavian Femoral Femoral, internal jugular, external jugular, or subclavian Femoral, internal jugular, external jugular, or subclavian Femoral, internal jugular, external jugular, or subclavian Femoral, internal jugular, or subclavian
Minimum catheter length (cm)* 5 5 5 8–12 12–25 15–25 15–25
* The longer end of the catheter length range is for use in the subclavian veins, with the longest catheters needed for the left subclavian vein.
TABLE 49-4 Comparisons Between Central Venous Catheter Types Single-lumen Minimum outer diameter Smallest Infusion rate Moderate Simultaneous infusions, or infusion while monitoring Length Allows device insertion (pulmonary artery lines and transvenous pacemakers)
No
Multiple-lumen Intermediate Lowest (resuscitation catheters with larger lumen available) Yes
Varies, fairly long No
Long No
Sheath (Cordis) Largest Fastest (for central lumen; side port is slower) Yes, if central lumen and side port both used Short Yes
CHAPTER 49: Central Venous Access
the shoulder blades as this can decrease the distance between the clavicle and first rib, compress the subclavian vein, and make the procedure more difficult.33 Place the patient supine or in slight reverse Trendelenburg if femoral vein catheterization is being attempted. The reverse Trendelenburg position will increase the cross-sectional area of the femoral vein.34 The Trendelenburg position is contraindicated due to the risk of venous air embolism. Slight external rotation and abduction of the extremity may increase the amount of femoral vein accessible for cannulation.35 It is easier for a righthanded Emergency Physician to perform the procedure standing on the patient’s right side, regardless of which femoral vein is being accessed. The opposite is true for those that are left-handed. Identify the anatomic landmarks for the procedure after positioning the patient. Clean any dirt and debris from the area of the puncture site. Apply povidone iodine or chlorhexidine solution and allow it to dry.36 It is recommended to prepare the entire neck and clavicular area if the internal jugular or subclavian routes are attempted so that, if access to one site is unsuccessful, another site may be accessed without re-prepping and draping. Due to the risk of inducing a pneumothorax, attempts at contralateral internal jugular or subclavian vein cannulation after an unsuccessful attempt must be delayed until a chest radiograph is checked to prevent bilateral pneumothoraces. Infiltrate the subcutaneous tissues at the needle puncture site with a generous volume of local anesthetic solution, including any areas that will be used for suturing the catheter in place. This allows the local anesthetic to diffuse throughout the area and take effect before the main procedure begins. Any distortion of anatomic landmarks caused by anesthetic infiltration decreases as the anesthetic is absorbed into the subcutaneous tissues. Apply electrocardiographic monitoring, pulse oximetry, and noninvasive blood pressure monitoring to the patient and administer supplemental oxygen. Electrocardiographic monitoring during insertion of a central line is recommended due to the risk of ventricular dysrhythmias should the guidewire or catheter enter the right ventricle. It is preferable to have a designated person—physician or nurse—whose only job is to watch the monitoring equipment. The patient’s face and chest will be draped for the internal jugular or subclavian vein cannulation procedure. The Emergency Physician will be focused on the procedure and unaware of any sudden patient deterioration, ventilator disconnect, or other irregularities. Resuscitation equipment should be immediately available. A postinsertion chest radiograph to verify line placement and the lack of a pneumothorax must be immediately available. Prepare for the procedure. Apply sterile gloves, a sterile gown, and a face mask. Some Emergency Physicians prefer to double-glove. If one glove becomes contaminated, it can be discarded and the procedure continued without interruption. Open the desired venous access kit using aseptic technique on a bedside table. Perform a quick inventory and identify all necessary equipment before beginning the procedure. Set up a sterile field next to the patient and within easy reach. Place the equipment that must be immediately
TABLE 49-5 Comparison of Central Venous Catheterization Methods Seldinger Insertion needle Small Speed Slowest Number of steps 4+ Risk of catheter shear None Catheters and lumens available Single- or multiple-lumen, sheath/introducer Rate of infusion Highest (with sheath)
317
at hand on the sterile field. This includes a sterile drape, syringe, large-bore hollow needle, guidewire, and gauze squares. Any other equipment, including the catheter itself, may be temporarily left in the kit. Never use the patient as a table. If they move, everything can fall onto the floor. A needlestick injury can occur from the falling needles or if the instinct to grab the falling equipment occurs.
INTERNAL JUGULAR VEIN CATHETERIZATION TECHNIQUES CENTRAL APPROACH TO THE INTERNAL JUGULAR VEIN While an internal jugular vein cannula can be inserted using the over-the-needle and through-the-needle techniques, the Seldinger technique is often preferred.37,38 See Chapter 47 and Table 49-5 for a more complete discussion. The Seldinger technique uses a flexible guidewire, inserted through a special thin-walled hollow needle, to guide a catheter of any desired length through the skin and into the central circulation. This technique is described below and summarized in Table 49-6. Clean, prep, and drape the area as described previously. Place the patient in the Trendelenburg position with their head down 15° to 30°. Slightly rotate the patient’s head away from the side that will be cannulated. Excessive rotation will distort the anatomic landmarks and may bring the internal jugular vein closer to the carotid artery. Several cardinal rules for the insertion of the catheter should be observed. Always occlude the open hub of a needle or catheter in a central vein to prevent an air embolism. Never let go of the guidewire, so as to prevent its embolization into the central venous circulation. Never apply excessive force to the guidewire on insertion or removal. Doing so may injure the vessel, break the guidewire, and/or embolize the guidewire. Attach the thin-walled introducer needle to a 5 mL syringe containing 1 mL of sterile saline or local anesthetic solution. The specially designed introducer needle included with the catheter should be used, as it has a relatively thin wall and a larger internal diameter relative to its external diameter. It has a shorter bevel than a conventional hypodermic needle. It also has a tapered hub to guide the guidewire into the needle proper. If there is doubt about the exact location of the vein, it may first be located with a small “finder” needle. Insert a 25 or 27 gauge needle attached to a 5 mL syringe through the skin puncture site previously chosen. Advance the needle at a 30° to 60° angle to the skin while applying negative pressure to the syringe. A flash of blood signifies that the tip of the needle is within the vein. Note the depth and location of the vein. Remove the finder needle. Alternatively, the finder needle may be left in place for reference. Insert the introducer needle at a 30° to 60° angle at the apex of the triangle formed by the sternal and clavicular heads of the sternocleidomastoid muscle and the clavicle (Figure 49-4). This point is just lateral to the carotid artery pulse. Direct the introducer needle
Catheter-over-the-needle Large Fastest 1 Low Single-lumen only Moderate
Catheter-through-the-needle Largest Fast 2 Highest Single-lumen only Low to moderate
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TABLE 49-6 Summary of the Seldinger Method of Central Venous Cannulation* Step Action 1
Prep and drape the skin puncture site.
2 3 4
Anesthetize the puncture site if not already done. Uncap the distal lumen. Locate the vein using the finder needle and aspirating syringe.
5
Remove the finder needle, noting the direction and depth of the internal jugular vein. Or withdraw the needle slightly so it is outside the internal jugular vein and leave it in place as a guide Insert introducer needle on a syringe along the “finder’s” path until venous blood is aspirated. Alternatively, an introducer catheter and needle assembly can be used to cannulate the internal jugular vein; the needle is then withdrawn. Disconnect the syringe from the needle, immediately occluding the open needle hub to prevent air embolism. Insert the guidewire through the introducer needle and into the vein. Advance the guidewire into the vein to the desired depth or until ventricular ectopy is seen on the ECG monitor. Withdraw the introducer needle a few millimeters and use the scalpel to enlarge the puncture site slightly. Remove the introducer needle. Thread the dilator over the guidewire until it can be grasped outside the hub, then insert and withdraw the dilator. Thread the catheter tip over the guidewire and withdraw the guidewire from the skin until it can be grasped at the infusion hub. Insert the catheter to the desired depth; most catheters are marked in centimeters, with larger markings every 5 and 10 cm. Introducer sheaths should be inserted completely. Holding the catheter in place, remove the guidewire. Occlude the open hub with a gloved finger to prevent air embolism.
6
7 8 9 10 11 12 13 14 15 16 17
Attach a syringe to the catheter hub and aspirate blood, taking samples as desired; then flush the lumen with saline and begin the desired venous infusion. Verify intravenous placement before suturing the catheter in place
18 19
Remove the patient from the Trendelenburg position. Suture the catheter to the skin with sutures and tape.
20 21
Apply a dressing to the catheter site. Verify catheter tip position by chest X-ray.
Tips and caveats For internal jugular vein, prepping down to the clavicle and up to the jaw will enable an attempt at the ipsilateral subclavian vein (or vice versa). Anesthetize the suture sites also. Additional lumens may be flushed at this point or after insertion, as desired. Internal jugular vein should be reached within 3 cm. Stop advancing after 4–5 cm if the vein is not located. A few drops or a line of blood may be left on the skin as the finder is withdrawn to show the proper direction. Syringe must have a nonlocking hub. A little saline in the syringe allows any occluding skin plug to be ejected. The vein is often located on withdrawal of the needle, since the friction of the large needle in the tissues can compress the internal jugular vein. Do not move the needle at all! Keep the hand holding the needle in contact with the patient’s skin to prevent movement. Do not move the needle! Do not force the guidewire—it should pass easily! The guidewire must be securely in the vein, not just in the subcutaneous tissue. Keeping the needle in place eliminates any possibility of cutting the guidewire. Never let go of the guidewire! Always keep a firm grip on the guidewire! Never let go of the guidewire. The tip of the catheter should be in the superior vena cava, at the level of the manubriosternal angle. Do not apply excessive force to the guidewire. If it is trapped, withdraw the catheter a few centimeters and try again. Do not break the wire! Other lumens may be aspirated, flushed, and clamped. If the patient’s blood travels up the intravenous tubing, the catheter is in the carotid artery! Take care not to puncture the catheter or to occlude it with a tight suture Catheter tip must be in the superior vena cava, not in the right atrium. Tip should be above the azygos vein and the carina, with the tip parallel to the vessel wall.
* The central approach to the internal jugular vein is used as an example, although the same technique is used for other approaches and central veins.
toward the ipsilateral nipple. Shallower angles make it necessary to traverse a greater amount of subcutaneous tissues and structures before entering the vessel. Steeper angles make insertion of the catheter over the guidewire difficult, as the guidewire tends to kink. Shallower angles are generally necessary in children whose vessels are smaller. Inject a small amount of the fluid in the syringe to remove any skin plug that may block blood return once the vein has been penetrated. Apply negative pressure to the syringe by withdrawing the plunger. Advance the introducer needle into the vein (Figure 49-10A). If the vein is not located within 3 to 5 cm of the skin—this distance will vary depending on the patient’s size and the target vessel’s location—stop advancing the introducer needle. Withdraw the
needle slowly while continuing to aspirate. Often, the vessel will have been completely traversed and no blood will return due to collapse of the vein by the pressure of the skin being forced inward as the introducer needle passes through it. Under normal physiologic conditions, veins have very low pressures within them and are easily collapsed by external pressure. If no blood is aspirated while withdrawing the needle, withdraw the introducer needle to the subcutaneous plane and redirect it slightly medially. Avoid putting continuous pressure on the carotid artery pulse, as even gentle pressure may collapse the internal jugular vein (Figure 49-3B). Stabilize and hold the introducer needle perfectly still with the nondominant hand once blood returns in the syringe. The carotid artery has been entered if the blood is bright red and/or forces
CHAPTER 49: Central Venous Access
319
FIGURE 49-10. The Seldinger technique. A. The vein is punctured by the introducer needle and blood is aspirated. B. The syringe has been removed. The guidewire is inserted through the introducer needle and into the vein. C. The introducer needle and guidewire sleeve are withdrawn over the guidewire. D. The skin puncture site is enlarged. E. The dilator is advanced over the guidewire until the hub is against the skin; then it is removed. F. The catheter is advanced over the guidewire and into the vein. G. The guidewire is withdrawn through the catheter.
the plunger of the syringe back. Remove the syringe. Blood should flow slowly and freely from the hub of the needle. The introducer needle is in the carotid or subclavian artery if blood squirts out the introducer needle hub. If blood dribbles out or does not flow from the hub and the patient has spontaneous circulation, reattach the syringe and reposition the introducer needle until free flow is obtained. Occlude the open hub of the introducer needle with the thumb of the nondominant hand while keeping the small finger of the hand in contact with the patient’s skin. The Emergency Physicians proprioceptive reflexes will prevent movement of the introducer needle by maintaining contact with the patient’s skin.
Even a millimeter of movement may result in failure of the needle tip to stay within the lumen of the vein. Prepare the guidewire (Figure 49-11). Grasp the guidewire and its sleeve with the dominant hand. The tip of the guidewire has a “J” shape when the sleeve is retracted (Figure 49-11A). Slide the sleeve forward to straighten out the “J” of the guidewire (Figure 49-11B). Insert the wire sleeve into the hub of the introducer needle (Figures 49-10B & 49-11C). Advance the guidewire through the sleeve and into the introducer needle. Never let go of the guidewire! One end of the wire must always be held to prevent loss of the wire and embolization into the central circulation.
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SECTION 4: Vascular Procedures
A
A
B
B
C FIGURE 49-11. Guidewire preparation. A. The plastic sleeve is retracted, showing the “J” tip. B. The plastic sleeve is advanced to cover the guidewire tip, allowing the wire to be threaded into the introducer needle. C. The sleeve is inserted into the hub of the introducer needle.
Do not simply reverse the guidewire if the sleeve used to straighten the curved end of the guidewire is lost. The straight end of the guidewire can puncture the wall of the vein. Grasp the guidewire between the fourth and fifth fingers and the palm of the dominant hand (Figure 49-12A). Apply gentle traction on the curved guidewire tip with the thumb and the second and third fingers in order to straighten the guidewire (Figure 49-12B). The guidewire can then be inserted into the introducer needle hub without the use of the sleeve. Advance the guidewire through the introducer needle and into the vein (Figure 49-10B). The guidewire should advance easily into the vein. Never force the guidewire. Guidewire resistance may indicate that the introducer needle is not within the vein, is against the wall of a vessel, or is caught as the vessel bends. Slightly withdraw the guidewire, rotate it slightly, and readvance it. The use of force will kink the guidewire and may cause it to damage the vein and adjoining tissues. Advance the guidewire 5 to 10 cm into the vessel or until ectopic beats are seen on the cardiac monitor. Withdraw the introducer needle and guidewire sheath while securely holding the guidewire (Figure 49-10C). Grasp the guidewire with the
FIGURE 49-12. Straightening the “J” tip. A. Grasp the guidewire between the ring and small fingers and the palm. B. Apply traction using the thumb and index fingers, stretching the outer coil of the wire over the solid core to straighten the “J” tip.
nondominant hand as soon as the guidewire is visible between the tip of the introducer needle and the skin. Finish removing the needle over the guidewire. Make a small incision in the skin adjacent to the guidewire using a #11 scalpel blade (Figure 49-10D). Place the dilator over the straight end of the guidewire (Figure 49-10E). Advance the dilator over the guidewire, through the skin, and into the vein. A slight twisting motion of the dilator as it is advanced may aid in its insertion. Continue to advance the dilator until its hub is against the skin. Do not release hold of the guidewire at any time. Remove the dilator over the guidewire. Place the catheter tip over the guidewire. Advance the catheter over the guidewire and into the vein to the desired depth (Figure 49-10F). Do not release hold of the guidewire. Gently rolling or twisting the catheter between the thumb and the forefinger may aid in its advancement. Hold the catheter securely in place and remove the guidewire (Figure 49-10G). Occlude the open catheter lumen with a sterile-gloved finger to prevent an air embolization and excessive blood loss. Attach a syringe to the catheter hub and aspirate blood to confirm that the catheter is within the vein. Withdraw any necessary blood samples from the catheter. Attach infusion tubing or a heparin lock to the port and flush the catheter to prevent a blood clot from obstructing the lumen. If a multilumen catheter is inserted, flush any other lumens after first withdrawing any air (Figure 49-13).
CHAPTER 49: Central Venous Access
321
TABLE 49-7 Comparison of Subclavian Vein Cannulation Routes Infraclavicular approach Supraclavicular approach Entry site Just inferior to the clavicle 1 cm lateral to the at the midclavicular line clavicular head of the sternocleidomastoid muscle, 1 cm posterior to the clavicle Needle orientation Keep as close to the Tip aimed 10° anterior coronal plane as to the coronal plane possible Needle bevel and Medially and caudally Medially “J” wire directed Aim toward Just posterior to the Contralateral nipple, sternal notch needle bisects angle formed by the clavicle and the clavicular head of the sternocleidomastoid muscle Distance from skin 3–4 cm 2–3 cm to subclavian vein
FIGURE 49-13. Aspiration and flushing of catheters. A. Any air in the lumen of the tubing is aspirated into the syringe of flush solution. The syringe must be held upright, as shown. B. Stop aspirating once all the air is removed from the catheter and blood begins to enter the syringe. C. Flush solution is injected until the lumen is filled and contains no blood. This usually requires 2 to 4 mL of flush solution.
Securely attach the catheter to the skin with nylon or silk sutures. Cover the skin puncture site with a sterile dressing.
ANTERIOR APPROACH TO THE INTERNAL JUGULAR VEIN The skin puncture site is at the anterior border of the sternal head of the sternocleidomastoid muscle, just lateral to the carotid artery and at the level of the cricoid cartilage (Figure 49-5). Enter the skin at a 45° to 60° angle. Direct the introducer needle toward the ipsilateral nipple. The internal jugular vein in an adult should be encountered within 3 to 5 cm. If the vein is not encountered by 5 cm, withdraw the tip of the introducer needle to the subcutaneous space and redirect it slightly medially. The remainder of the procedure is as described for the central approach above and in Table 49-6.
POSTERIOR APPROACH TO THE INTERNAL JUGULAR VEIN Enter the skin at the posterior edge of the sternocleidomastoid muscle, one-third of the way from the clavicle to the mastoid process (Figure 49-6). Alternatively, the point where the external jugular vein crosses the lateral border of the sternocleidomastoid muscle can be used. Direct the introducer needle under the sternocleidomastoid muscle at a 30° to 45° angle to the skin and toward the sternal notch. Place the index finger of the nondominant hand in the sternal notch to provide a landmark with the patient draped. In an adult, the internal jugular vein should be encountered within 5 cm. This approach is not recommended in children. The remainder of the procedure is as described for the central approach above and in Table 49-6.
SUBCLAVIAN VEIN CATHETERIZATION TECHNIQUES The technique is identical to that described above for internal jugular vein cannulation except for the puncture site. Two techniques, infraclavicular and supraclavicular, are described below and summarized in Table 49-7.
INFRACLAVICULAR APPROACH TO THE SUBCLAVIAN VEIN The infraclavicular approach to the subclavian vein is most often used. It is commonly thought to be easier to perform and less likely to result in a pneumothorax than the supraclavicular approach, although data for this belief are lacking.39 Some Emergency Physicians prefer not to use a finder needle for infraclavicular subclavian vein cannulation as there is no danger of penetrating the carotid artery. This also makes as few needle passes near the pleura as possible in order to decrease the risk of an iatrogenic pneumothorax. Estimate the distance from the skin puncture site to the superior vena cava (i.e., the manubriosternal junction). Several different skin entry sites are described in the literature. Some feel that the preferred entry site is 1 cm caudal to the junction of the medial and middle thirds of the clavicle. The subclavian vein lies just posterior to the clavicle at this site (Figure 49-14). The first rib lies between the pleural dome and the subclavian vein. Direct the introducer needle just superior and posterior to the suprasternal notch while staying as close to the frontal (coronal) plane as possible. The needle and syringe should be parallel to the bed (Figure 49-14A). Placing the nondominant index finger in the sternal notch will help to guide placement (Figure 49-14A). Some Emergency Physicians prefer to enter the skin inferior to the clavicle at the deltopectoral groove, or the point just lateral to the midclavicular line along the inferior surface of the clavicle. This is the point where the skin may be maximally depressed. Direct the introducer needle parallel to the bed and toward the sternal notch. This entry site may make it easier to keep the introducer needle in the coronal plane. The distance before entering the subclavian vein is longer than in the preceding approach and the protection offered by the first rib is lost.
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FIGURE 49-14. Infraclavicular approach to subclavian vein cannulation. A. Frontal (oblique) view of the procedure. B. Sagittal section through the medial third of the clavicle. Note the proximity of the pleura and subclavian artery.
One additional landmark can be used to identify the skin puncture site. Palpate the bony tubercle, or protrusion, on the inferior surface of the clavicle and approximately one-third to one-half the length of the clavicle from the sternoclavicular joint. The advantage of this site is that it is a definitive landmark and avoids approximating distances, as described for the other sites above. Insert the introducer needle parallel to the bed and aimed just posterior to the sternal notch. The bevel of the introducer needle should be oriented caudally, as should the “J” in the guidewire (Figure 49-15). This position will allow the guidewire to enter the innominate vein and superior vena cava rather than being directed upward into the internal jugular vein or across to the contralateral subclavian vein (Figure 49-15). Once venous blood is aspirated, the Seldinger technique for catheter insertion is otherwise the same as previously described for internal jugular vein cannulation. Aspiration of bright red blood under pressure indicates subclavian artery puncture, which will be incompressible. Remove the introducer needle and observe the patient for signs of significant hemorrhage over the next several hours. Aspiration of air indicates penetration of the pleura. Observation with serial chest radiographs for at least the next 6 to 24 hours is essential to evaluate the size of the potential resulting pneumothorax.
SUPRACLAVICULAR APPROACH TO THE SUBCLAVIAN VEIN While most Emergency Physicians are more comfortable with the infraclavicular approach to the subclavian vein, the supraclavicular approach offers some distinct advantages. The supraclavicular subclavian vein is closer to the skin. The route from a right-sided skin puncture site to the superior vena cava is more direct. It allows easier access to the superior vena cava while avoiding the hazards of a left-sided puncture (i.e., the thoracic duct). The skin entry site is
FIGURE 49-15. Introducer needle bevel orientation for subclavian vein cannulation. Varying the orientation of the introducer needle bevel for infraclavicular and supraclavicular techniques helps guide the “J” shaped guidewire into the superior vena cava.
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FIGURE 49-16. Supraclavicular approach to subclavian vein cannulation. A. From the insertion point 1 cm superior to the clavicle and 1 cm lateral to the border of the sternocleidomastoid muscle, direct the introducer needle tip at a 45° angle to the transverse and sagittal planes and slightly anterior toward the contralateral nipple. B. Sagittal section through the medial third of the clavicle. Note that the introducer needle track must be directed anteriorly to avoid the subclavian artery and the dome of the pleura.
more accessible during CPR and requires less interruption of external chest compressions.40 With experience, the complication rate for the supraclavicular approach is probably lower than that for the infraclavicular approach.39,41 Estimate the distance from the skin puncture site to the superior vena cava to guide the catheter insertion depth. The skin is entered at a point 1 cm lateral to the lateral border of the clavicular head of the sternocleidomastoid muscle and 1 cm superior to the clavicle (Figure 49-16).42 The introducer needle should bisect the angle formed by the clavicle and the lateral border of the sternocleidomastoid muscle (Figure 49-16A). Direct the introducer needle toward the contralateral nipple or a point just superior and posterior to the sternal notch. Orient the introducer needle bevel medially (Figure 49-15). The subclavian vein should be entered within 2 to 3 cm in an adult. The length of catheter inserted will be 2 to 4 cm less than that for the infraclavicular approach. Alternative skin entry sites and approaches have been described. Enter the skin 1 cm medially and 1 cm superiorly to the midpoint of the clavicle with the introducer needle directed toward the ipsilateral sternoclavicular joint.43 The skin can be entered just posterior to the clavicle, at the junction of the medial and middle third of the clavicle, with the introducer needle directed toward the ipsilateral sternoclavicular joint and parallel to the coronal plane.44 This last approach is probably the simplest, although the study cited was performed on cadavers rather than live patients.
AXILLARY VEIN CATHETERIZATION TECHNIQUE The axillary vein must be accessed using US guidance and not blindly using landmarks. Place the patient supine with their arm abducted in a comfortable position. A recent US study demonstrated no benefit of arm abduction in increasing axillary vein
size or decreasing arteriovenous overlap.16 Locate the axillary vein using a high frequency, 5 to 10 MHz, US probe. Place the US probe, with the marker pointing cephalad, just below the clavicle at approximately its middle third. Identify the axillary artery, axillary vein, and the pleura to obtain proper orientation. Manual compression and color flow Doppler can be used to differentiate between the vein and the artery. Follow the axillary vein laterally on the chest until overlap with the artery is minimized and the pleura is out of the view of the probe. Rotate the US probe into a parallel orientation in respect to the axillary vein with the probe marker toward you to obtain a long axis view of the axillary vein. Gently pivot the US probe in a cephalad and caudal direction to clearly differentiate the axillary vein from the axillary artery. Slight movements of the probe will alter the US image between the vein and artery. It is recommend to stabilize the US probe by resting your distal forearm and wrist against the anterior chest. Note the depth of the vein to ensure that the central venous catheter needle will be able to puncture the vessel. The remaining details of the technique are as described in Chapter 50 (US-Guided Vascular Access).
FEMORAL VEIN CATHETERIZATION TECHNIQUE This technique is often performed blind using landmarks. It can also be performed under US guidance. The use of an ECG monitor is still recommended even though the short guidewire may not reach the heart. Particular care must be taken if the patient has a preexisting left bundle branch block, as complete heart block may result if the guidewire or catheter enters the right ventricle.28 Premeasuring from the insertion site to the xiphoid process will give the maximum depth of catheter insertion. The introducer needle should enter the skin 2 to 4 cm inferior to the midpoint of the inguinal ligament and 1 cm medial to the
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FIGURE 49-17. Femoral vein cannulation. The skin puncture site is 1 cm medial to the femoral artery pulse and 2 to 4 cm inferior to the inguinal ligament. Direct the introducer needle posteriorly at a 45° to 60° angle while aspirating.
femoral artery pulse (Figure 49-17). In an infant or young child, the introducer needle should enter the skin 1 to 2 cm inferior to the inguinal ligament and 0.5 cm medial to the femoral artery pulse. The cannulation technique is as described previously for the internal jugular vein. Two site-specific considerations deserve mention. The use of a finder needle is unnecessary, since there are no vital structures in the area other than the femoral artery that is compressible if it is punctured. The introducer needle is directed at a 45° to 60° angle to the skin and parallel to the long axis of the thigh. Shallower angles may be necessary in very small and thin patients. Use caution to avoid puncturing the posterior wall of the vein above the inguinal ligament, since this can result in a retroperitoneal hemorrhage.
MULTIPLE-LUMEN CATHETERS Prior to skin puncture, remove the cap from the distal port’s injection hub. It is usually marked “distal.” The other lumens may be flushed with saline or heparin solution and recapped or left capped and flushed later (Figure 49-13). Heparin concentrations no higher than 100 U/mL should be used to avoid temporarily anticoagulating the patient.45 The introducer needle and guidewire are inserted as described previously. Place the multiple-lumen catheter tip over the guidewire. Advance the catheter until the guidewire emerges from the distal port hub (Figure 49-18). Insert the catheter to the desired depth. Remove the guidewire. Flush the distal lumen and connect it to the desired infusion. If not done previously, aspirate and flush the other lumens with the desired solution (Figure 49-13).
ALTERNATIVE TECHNIQUES USE OF THE SELDINGER-HUB INTRODUCER CATHETER Some central venous access kits include a catheter-over-the-needle with a tapered hub that can be used in place of the thin-walled introducer needle. This technique has the advantage of allowing the introducer catheter to remain in place while venous placement is verified. It provides less likelihood of the vein being lost as the aspiration syringe is removed and the guidewire advanced. A guidewire advanced through the introducer catheter cannot become sheared off, as when it is inserted through the needle. The vein is entered with the catheter-over-the-needle assembly attached to an aspirating syringe, as described previously. Once the flashback of blood is obtained, advance the catheterover-the-needle 2 mm further into the vein. This will ensure that the tip of the introducer catheter is within the vein. Hold the hub of the needle securely. Advance the catheter into the vein until its hub is against the skin. Withdraw the needle. If necessary, the introducer catheter may be attached to a pressure transducer and the venous waveform verified to confirm venous rather than arterial placement. Blood gas measurements may also be performed. Advance the guidewire through the introducer catheter and into the vein. The remainder of the procedure is as previously described.
PERCUTANEOUS INTRODUCER SHEATH (CORDIS) The insertion technique differs slightly from those described above (Figure 49-19). Locate the vein, insert the needle followed by the guidewire, and remove the needle leaving the guidewire in place as described previously. Insert the plastic dilator into the lumen of the sheath. The entire assembly must be advanced over the guidewire as a unit rather than utilizing separate dilation and insertion steps (Figure 49-19C). A correspondingly larger skin nick must be made with the scalpel, since the sheath is usually of larger diameter than a catheter. Advance the dilator–sheath unit over the guidewire (Figure 49-19C) and into the vein (Figure 49-19D). A twisting motion may aid in its advancement. Continue to advance the unit until the hub of the sheath is against the skin (Figure 49-19E). Remove the guidewire and dilator as a unit (Figure 49-19E). The remainder of the procedure is as described previously.
US-GUIDED CENTRAL VENOUS ACCESS The use of bedside US to guide central venous access is becoming more common. The availability of US, its low cost, portable units, and training during residency are making its use standard procedure for central venous line placement. Please refer to Chapter 50 for the complete details of US-guided vascular access.
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FIGURE 49-18. Inserting a multiple-lumen catheter. The guidewire exits through the uncapped distal port. The proximal port(s) must be clamped or capped to prevent air embolism.
PEDIATRIC CONSIDERATIONS The anterior or central approach to the internal jugular vein is preferred for children. Appropriate catheter sizes and lengths are shown in Table 49-3. The child must be sedated and immobilized prior to attempts at cannulation of the internal jugular or subclavian vein. The femoral vein is the vein of choice if central venous access is needed in a combative child who cannot be completely restrained. The patient need not be in the Trendelenburg position, the consequences of a misdirected needle are less severe, and the procedure is less threatening as the face is not draped. A shallower angle of skin entry than in an adult is necessary to access the femoral vein. Enter the skin 1 to 2 cm inferior to the inguinal ligament and 0.5 mm medial to the femoral artery. Subclavian vein access in the small child can be difficult due to the anatomic relationships of the vessels as previously described. Despite this, the subclavian vein, in addition to the femoral vein, can be safely and effectively accessed in children less than 1 year of age.46
ASSESSMENT
FIGURE 49-19. Inserting an introducer sheath. A. The sheath. B. The dilator. C. The dilator is inserted into the sheath and the unit is threaded over the guidewire. D. Advance the unit over the guidewire and into the vein using a twisting motion (arrow). E. The dilator and guidewire are removed as a unit, leaving the sheath in place.
Examine the patient. Examine the lung fields carefully to exclude a significant iatrogenic pneumothorax. Recheck the patient’s vital signs frequently after the procedure. Obtain a portable anteroposterior chest radiograph to verify line tip placement in the superior vena cava and rule out an iatrogenic pneumothorax. Check the catheter site for hematoma formation or hemorrhage along the dilated catheter track. Control any hemorrhage with direct pressure. US, if immediately available, can be used postinsertion to determine the presence or absence of an iatrogenic pneumothorax. Detection of an anterior pneumothorax in a supine patient has been shown to more sensitive using US than standard plain radiographs.47,48 The use of US does not negate the need to determine catheter location by plain radiographs. US may be a useful tool when postline chest radiographs are delayed or the patient suddenly decompensates during or immediately after central line placement. Check the function of the catheter by aspiration and infusion through all ports, as discussed above. A proximal lumen may be extravascular if it fails to aspirate blood easily. A catheter may be exchanged over a guidewire as long as the distal tip of the catheter is definitely intravascular. Do not attempt to advance the catheter once the guidewire has been removed.
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Check the position of the catheter tip on the chest radiograph. The catheter must not be in the heart due to the risk that erosion through the thin right atrial wall will result in a pericardial hemorrhage and tamponade.49,50 Landmarks for an internal jugular or subclavian vein catheter tip include the following: above the level of the carina, above the azygos vein, and at/above the manubriosternal junction. The tip of the catheter should be parallel to the vein to prevent erosion through the wall of the vein. If the catheter crosses over to the opposite subclavian vein and the patient cannot tolerate an attempt at repositioning, it may be used for intravenous infusion. Lines placed from the subclavian vein into the jugular system must be replaced. Catheters in or below the right atrium must be pulled back immediately to prevent any arrhythmias and perforation of the myocardium. It is important to ensure that the catheter is within a vein and not an artery. This can be accomplished by US as described in Chapter 50. An arterial line monitoring setup can be attached to the catheter to measure intravascular pressures. This is time consuming, expensive, and takes some time to prepare. A device was recently approved by the FDA to assist in this evaluation. The Compass Vascular Access pressure measurement device (Mirador Biomedical, Seattle, WA) is a disposable, single patient use, digital manometer that attaches between the syringe and introducer needle. It provides a digital pressure measurement through the needle when it is within the blood vessel. It also provides pressure measurements while the guidewire is being inserted through the needle. Most femoral vein catheters can be fully inserted. Premeasurement is recommended to make sure that the catheter tip will not reach the right atrium. If there is any doubt about the catheter position, postinsertion abdominal and chest radiographs should be obtained. The tip of the catheter must be at or below the xiphoid process of the sternum. Reassess the distal neurovascular status of the lower extremity after line placement.
AFTERCARE The catheter must be sutured in place to prevent malpositioning of the line. Tie a surgeon’s knot at the skin, then secure the suture to the hole(s) provided in the catheter wings. The straight needle contained within most central venous access kits can be difficult to use and it poses a needlestick risk. One option is to use nylon suture on a curved needle and a laceration repair kit. This requires additional equipment and at an additional cost. Another option is to use a needle cap or syringe contained within the kit to protect against the advancing straight needle puncturing your finger.51,52 Use the cap to apply counter pressure against the skin as the straight needle tip exits the skin. A catheter clamp is often provided in the kit for longer catheters. It too should be sutured in place. The clamp holds the catheter in place by friction. It is not a guarantee that the catheter will not move. The catheter depth should be checked daily by inspection and by frequent chest radiographs. Movement of the patient’s head and neck may move the tip of the internal jugular vein catheter by as much as 4 cm.53 Introducer sheaths have large lumens and present a significant risk of causing an air embolism. Cap the main lumen if it is not being used for an infusion. Any built-in diaphragm is not a reliable means of preventing an air embolism.54 Do not use the dilator as an occluder or infusion port, as the stiff plastic can easily erode through the wall of the vein. An occlusive dressing can be used if no occluder is available. The skin puncture site should be checked regularly for signs of infection. Cellulitis or purulent drainage requires a new central venous line at another site. Remember to restrain any patient who is uncooperative so as to prevent inadvertent removal of the central line.
While the short-term infection rate of femoral lines compares favorably with that in other central lines, some precautions are necessary to prevent soilage of the site.20,55 Consider the judicious use of bladder catheterization in patients who are incontinent of urine and of rectal tubes in patients with loose stools. Patients with percutaneous femoral vein catheters must be confined to bed to prevent catheter dislodgment and hemorrhage around the catheter. Frequent assessment for venous thrombosis in the lower extremity is essential. It is recommended that femoral lines be discontinued when an alternative venous access site is available or within 3 days, whichever is sooner.56
REMOVAL OF THE CENTRAL VENOUS CATHETER It has been, and sometimes still is, routine policy in some institutions to change all central venous lines placed in the Emergency Department when the patient arrives in the Intensive Care Unit. It was believed that these lines placed in the Emergency Department were “dirty” and at a higher risk of infection. This practice results in an additional procedure, the additional time and cost of the procedure, the associated discomfort or pain of the procedure, and the potential for complications. A recent study demonstrated that the infection rate of central venous lines placed in the Emergency Department using aseptic technique was no different than those placed in the Intensive Care Unit.57 When removing a central venous catheter from the internal jugular or subclavian vein, place the patient in the Trendelenburg position. To remove a femoral vein catheter, place the patient supine. Remove the dressing overlying the skin puncture site. Cut the suture securing the catheter to the skin. Ask the patient to exhale and hold their breath. Briskly remove the catheter and cover the puncture site with a gauze dressing. The track from the skin surface to the vein can be a source of a fatal venous air embolism.58 If the catheter had a large diameter or remained in place for more than 2 to 3 days, apply an occlusive dressing to the site for the first 1 to 2 days after the catheter has been removed. The skin puncture site should be observed for signs of infection twice a day for 48 hours.
COMPLICATIONS Mechanical complications can occur. The needle and/or guidewire may puncture the lateral or posterior wall of the vein.59–62 This can result in a hematoma formation, arterial puncture, arterial cannulation, and an arteriovenous fistula. The use of US guidance does not prevent these complications.59–61 The guidewire or catheter can break, fragment, or become knotted intravascularly. The guidewire can become a venous embolus if it completely enters the vein.
INTERNAL JUGULAR VEIN CATHETERIZATION Internal jugular venous access has a myriad of potential complications.49,63–66 Infection can be either at the local site or in a systemic line due to bacteremia and sepsis. A pneumothorax can occur during line placement. A hemothorax may be life-threatening, especially if a venopleural fistula is created. A chylothorax occurs if the thoracic duct is lacerated. Occasionally, carotid artery puncture can result. It may be complicated by a stroke if the blood supply to the brain is interrupted or if a plaque embolizes. Airway compromise can occur due to the formation of a hematoma and compression of the airway. An air embolism can occur if the catheter lumens are left open to the air during insertion or if connections loosen and separate at a later time. Right ventricular irritation from the catheter tip can cause cardiac dysrhythmias. Puncture of the right atrial wall can lead to pericardial tamponade and death. The guidewire can
CHAPTER 50: Ultrasound-Guided Vascular Access
become entrapped, necessitating surgical or interventional radiology removal. Embolization of the guidewire or catheter parts occurs with improper use of the equipment. Anaphylactic reactions to antibiotic-impregnated catheters have been reported. The cardiac monitors should be observed during the procedure to prevent the death of a critically ill patient from being unnoticed while the catheter is being inserted. Thrombosis of the catheter or vein may lead to pulmonary embolism. Many of these complications can be prevented or minimized with the use of US guidance. Karakitsos et al. showed a statistically significant difference between the blind and US-guided techniques with regard to arterial puncture, hematoma formation, hemothorax, pneumothorax, and infection rate.67 All of these were in favor of the US-guided study arm. Multiple smaller studies have shown similar results in favor of the US-guided technique.2,68–72 There is no specific report of complication rates involving the thoracic duct, nerve injury, or thyroid injury. This is likely due to the extremely rare incidence of damage to these structures. Overall, US guidance has been shown to significantly reduce complications and improve patient safety for internal jugular vein access. Complications during catheterization occur in proportion to the operator’s inexperience.64 If the patient is unlikely to survive a mistake, the most experienced person available should perform the procedure!
SUBCLAVIAN VEIN CATHETERIZATION Complications of subclavian vein cannulation are similar to those of internal jugular vein cannulation, as described above. While there is no risk of carotid artery injury if the procedure is performed correctly, the subclavian artery can be lacerated if the needle is advanced too deeply. Malposition of the catheter tip, usually due to overinsertion of the catheter, is common. Lacerations of the thoracic duct can be avoided by performing the procedure on the right side, avoiding overpenetration with the introducer needle, and avoiding directing the needle too superiorly toward the junction of the subclavian vein and internal jugular vein. Other complications, such as injury to the brachial plexus and phrenic nerve, are uncommon but possible.73 They can be prevented by avoiding over-insertion of the needle during the procedure and avoiding needle paths superior and posterior to the subclavian vein. A pneumothorax is a very real risk with subclavian vein catheterization. The procedure should not be performed unless personnel are immediately available who can deal with this complication.74 The risk of a pneumothorax is probably higher in obese patients, who may have distorted anatomic landmarks and in whom a more acute angle is required to enter the subclavian vein. Patients with emphysema and COPD may have higher pleural domes and less pulmonary reserve in the event of a pneumothorax.
arteriovenous overlap. In either situation, correction with reverse Trendelenburg or proper leg positioning under US guidance may allow the Emergency Physician a better target for cannulation and reduce complications. During periods of severe hypotension or cardiac arrest, palpation of the femoral artery may not be feasible. This can lead to failed access or arterial cannulation. Hilty et al. demonstrated a higher rate of success and a decreased rate of arterial cannulation with US guidance during CPR.75 US guidance for femoral vein cannulation may not yet be a standard practice, but it may be a useful technique that can reduce the rates of complication of central venous cannulation.
SUMMARY Central venous access is often necessary in critically ill patients and in those with poor peripheral veins. Mastery of these techniques is essential for anyone who will be caring for acutely ill and unstable patients. While all approaches to the central circulation have acceptably low complication rates (1% to 5%) when performed by experienced providers, they all carry real risks to the patient.39,49 Be certain that there is no safer peripheral access alternative before placing a central venous line. The internal jugular vein is a good choice for central venous access in nonambulatory patients. The right internal jugular vein provides easy access to the superior vena cava for monitoring and for infusion of solutions too concentrated or irritating for peripheral veins. This route poses a slightly lower risk of complications than the subclavian route.64,66 The subclavian vein provides easy access to the central circulation. Subclavian vein catheters are more easily tolerated by awake and ambulatory patients than are internal jugular or femoral catheters. Subclavian vein cannulation does present very real risks to the patient that must be balanced against the need for the procedure and other alternatives. Subclavian vein access is the least preferred route in young children due to their small size, the proximity of the pleura, and the proximity of the subclavian artery. Femoral vein cannulation is an essential emergency skill. It allows the easiest central venous access in most patients with the lowest risk of catastrophic immediate complications compared to jugular and subclavian access procedures. US guidance for central venous access, specifically the internal jugular vein has rapidly become integrated into the practice of Emergency Medicine. Familiarity with US guidance is become a mandatory skill for the Emergency Physician when placing central venous lines. Refer to Chapter 50 regarding the complete details of US-guided central venous access.
FEMORAL VEIN CATHETERIZATION Deep venous thrombosis of the femoral and more distal veins is a recognized complication of femoral venous lines.56 Inadvertent cannulation of the femoral artery may occur. This is particularly true during an episode of severe hypotension or cardiac arrest. If such an episode goes unrecognized, infusion of vasopressors into the artery may result in ischemic injury to the distal limb. Even though US guidance for femoral vein cannulation does not currently have large studies with robust data in the literature, anatomical visualization can be useful in multiple situations. Recent research depicting the anatomical variation and overlap between the femoral artery and the femoral vein in normal patients brings to question the safety of blind or landmark based venous cannulation. In a stable patient with a palpable pulse, US guidance may aid in identifying a very small femoral vein and/or significant
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Ultrasound-Guided Vascular Access Srikar Adhikari
INTRODUCTION Central venous catheterization is essential in the management of critically ill patients seen in the Emergency Department (ED). It allows for fluid resuscitation, central venous pressure monitoring, pacemaker placement, and administration of vasoactive medications. Complications such as arterial puncture, hematoma, pneumothorax, hemothorax, and air embolus have been reported to occur in 5% to 20% of patients.1–3 Unsuccessful cannulation has
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been reported in up to 20% of cases.4,5 Central venous catheterization has traditionally been performed using surface anatomic landmarks as a guide to locate the veins. Catheterization is not always successful using the landmark method due to anatomical variations or obscured landmarks. Other factors such as obesity, shock, dehydration, intravenous drug abuse, congenital deformities, thromboses, and scarring can complicate the procedure. Ultrasound (US)-guided vascular access is widely supported in current medical practice. The use of US guidance for central venous cannulation has been endorsed by several medical societies and supported by numerous trials in the literature. US guidance has been shown to improve cannulation success rates, reduces mean insertion attempts, and reduce placement failure rates.6–11 US guidance allows the Emergency Physician to more precisely locate target vessels and also provide real time visualization of needle placement. Peripheral venous access is more commonly performed in the ED than central venous cannulation. Patients with a history of chronic kidney disease, intravenous drug abuse, vascular disease, organ transplantation, and obesity lack easily located peripheral venous sites. Obtaining peripheral intravenous (IV) access in these patients can be a challenge, even for the most experienced medical personnel. Multiple studies have shown US-guided peripheral IV access is safe and successful in these patients.12–17 US-guided peripheral IV access prevents the need for central venous catheterization and the pain of multiple needle sticks in many “hard-to-stick” patients.
ANATOMY AND PATHOPHYSIOLOGY It is important to recognize the differences in sonographic appearance between arteries and veins when performing US-guided vascular access. Arteries and veins can be distinguished by their size, shape, location, ability to be compressed, Doppler mode signal, and spectral Doppler waveforms. Arteries have relatively thick and hyperechoic (white) walls and anechoic (black) lumens. Veins have relatively thin and hypoechoic (gray) walls and anechoic (black) lumens. The thin-walled veins are usually oval, easily compressible, and have no pulsations on Doppler mode (Figures 50-1 & 50-2). Arteries are typically round in appearance and pulsatile on Doppler mode (Figure 50-1). Arteries and veins are often found adjacent to each other. Veins are usually larger in diameter than arteries in a well-hydrated patient (Figure 50-1). The anatomy relevant to the sonographic evaluation of central and peripheral veins is described in the following sections.
FIGURE 50-2. The US probe is used to apply external pressure to the soft tissues of the neck. The internal jugular vein collapses with gentle compression (CA, carotid artery; IJV, internal jugular vein; SCM, sternocleidomastoid muscle).
CENTRAL VEINS The internal jugular and femoral veins are commonly used for US-guided central venous catheterization. US-guided subclavian vein cannulation is technically more challenging because the vein runs for a significant distance under the clavicle. The clavicle obstructs the US beam and produces a large acoustic shadow, which makes US visualization of this area difficult. The internal jugular vein traverses the neck and is unopposed by bone, making it an ideal vein to visualize with US. The internal jugular vein lies underneath the bifurcation of the sternal and clavicular heads of the sternocleidomastoid muscle. It continues to run vertically downward in the neck, lying at first lateral to the internal carotid artery, and then lateral to the common carotid artery. It eventually enters the subclavian vein (Figure 49-2). The common femoral vein lies medial to the common femoral artery and inferior to the inguinal ligament. In the upper thigh, the superficial femoral and deep femoral veins unite to form the common femoral vein. The greater saphenous vein joins the anteromedial aspect of the common femoral vein below the inguinal ligament (Figure 50-3). The common femoral vein becomes the external iliac vein after it passes under the inguinal ligament.
PERIPHERAL VEINS
FIGURE 50-1. US image of the neck vessels. The internal jugular vein (IJV) is thinwalled and oval. The carotid artery (CA) is thick-walled and round.
The three veins of the upper extremity that are most commonly used for US-guided vascular access are the basilic, cephalic, and brachial veins. The venous drainage of the upper extremity consists of a deep system and a superficial system. The deep system includes radial and ulnar veins in the forearm that unite to form the brachial vein, which is the deep vein in the upper arm. The brachial vein lies next to the pulsatile and noncompressible brachial artery (Figure 50-4). It is not uncommon to find paired superficial and deep brachial veins. The two major superficial veins of the upper arm are basilic and cephalic veins. The cephalic vein arises from the radial aspect of the dorsal hand venous network, ascends proximally along the anterior border of the brachioradialis muscle, runs lateral to biceps muscle and joins axillary vein. The basilic vein begins in the ulnar side of the dorsal hand venous network, ascends along medial aspect of forearm and upper arm, and unites with the brachial veins to form the axillary vein.
CHAPTER 50: Ultrasound-Guided Vascular Access
FIGURE 50-3. US image of the femoral vessels. The common femoral vein (CFV) lies medial to the common femoral artery (CFA). The superficially located greater saphenous vein (GSV) enters the common femoral vein 2 to 3 cm below the inguinal ligament.
STATIC APPROACH TO VASCULAR ACCESS The static approach to vascular access involves confirming the location of the vein prior to performing the cannulation. Place the US transducer perpendicular to the course of the vein to visualize the vein and verify compressibility. Adjust the probe so that the target vein is in the center of the US monitor screen. This places the vein directly under the center of the US probe. Place a mark on the skin at the midpoint of the US probe to mark the vein location. To assess the path of the vein, repeat this process at a point 2 cm away and along the vein. These two points marked on the skin will serve as a guide to direct the needle. Determine how deep the vein is located. Look at the depth markers on the side of the US monitor screen. Remove the probe and prepare the patient as usual. Proceed with the catheterization. Insert the needle approximately 0.5 cm above or below the mark. Advance and direct the needle to the appropriate depth underneath the skin markings. If the patient changes position after marking the skin but before needle puncture, the patient must be re-imaged and the skin markings repeated prior to inserting the needle. The advantages of the static approach are its simplicity and that the US probe does not need to be prepared for the sterile portion of the procedure. The disadvantage of this technique is that the needle is not visualized in real time while performing the procedure.
DYNAMIC APPROACH FOR VASCULAR ACCESS The dynamic approach to vascular access involves inserting the needle into the vein under real time US guidance. Two techniques are used for the dynamic approach and they refer to the orientation of the US probe and target vein during the venipuncture. The short axis approach visualizes the vein in a cross section. The long axis approach visualizes the vein longitudinally. Each approach has its own advantages and disadvantages. The short axis approach provides better medial to lateral orientation of the needle in relation to the target vein and also allows for visualization of adjacent structures in the same image. Novice sonographers can learn the short axis approach more quickly and it can be performed in anatomic locations where space is limited such as the neck or the groin in an obese patient. One potential danger with the short axis approach is unseen penetration of the posterior wall of the target vein and adjacent structures. The long
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FIGURE 50-4. Transverse US view of the upper arm veins (BA, brachial artery; BAV, basilic vein; BV, paired brachial veins).
axis approach allows better depth and needle slope information. The entire needle can be tracked with this approach. The long axis approach provides much better visualization of the tip of the needle and its trajectory, thus avoiding inadvertent puncture of the posterior wall of the vein. The long axis approach requires more hand–eye coordination and is technically more difficult to learn.
INDICATIONS US can be used to mark the site of needle entry or provide real time guidance. Ideally, US guidance should be used for all internal jugular and femoral vein cannulations if the equipment is available. It should also be used for peripheral IV access in all “hard-to-stick” patients or when a peripheral vein is not visible or palpable. The use of US-guided peripheral IV access in the patient with difficult peripheral IV access can prevent the need for central venous access. It is highly recommended in the patient with poor anatomic landmarks, coagulopathies, anticoagulant use, a history of difficult IV access, DIC, thrombocytopenia, prior surgical interventions or radiation in the area, scarring on the skin above veins, intravenous drug abuse, obesity, hypotension, and severe dehydration.
CONTRAINDICATIONS There are no absolute contraindications to the use of US for central or peripheral venous access except lack of US training and experience.
EQUIPMENT • • • • • • • • • •
Ultrasound machine Ultrasound gel High frequency, 5 to 10 MHz linear array US probe Sterile US probe cover (clear plastic cover, US gel, and rubber bands) Povidone iodine or chlorhexidine solution Equipment for peripheral IV access (Chapters 47 and 48) Equipment for central venous access (Chapter 49) Water-soluble lubricant, sterile Translucent dressing (e.g., Tegaderm) 2 to 3 inch (in) long catheter-over-the-needle, various sizes
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PATIENT PREPARATION CENTRAL VENOUS ACCESS Position the patient the same as if performing central venous catheterization using the landmark method (Figure 50-5). Place the US machine across from where you will be standing to minimize the body movement required to view the US image. For internal jugular vein access, stand at the head of the patient with the US machine at the patients hips (Figure 50-5A). Place the
A
patient in the Trendelenburg position with their head turned to the contralateral side or kept in a neutral head position (Figure 50-5A). The relationship of the internal jugular vein to the carotid artery changes with head position. In the neutral position, the internal jugular vein assumes a more lateral position to the carotid artery. This minimizes the risk of arterial puncture while accessing the target vein. For femoral vein access, stand at the bedside adjacent to the patient’s hip with the US machine above the patient’s shoulder (Figure 50-5B). Place the patient in the reverse Trendelenburg position with their hip abducted and externally rotated (Figure 50-5B). This position enhances the success rate of catheterization by increasing the surface area of the femoral vein available for cannulation.18 Perform a preliminary scan prior to preparing the patient for the sterile procedure. Survey the underlying vasculature to confirm the patency of the target vein, determine the optimal site for venipuncture, and adjust the US machine settings to optimize the image. The ability of the vein to be compressed distinguishes artery from vein, confirms the patency of the vein, and reduces the risk of cannulating a thrombosed vein. Do not assess compressibility in the long axis. The US probe may slide off the vein and be seen as the vein lumen disappearing and misinterpreting it as being compressible. Clean and prep the skin at the access site as if performing a traditional central line placement. Follow strict aseptic technique and all barrier precautions during the procedure. The procedure can be performed by either one person (the Emergency Physician) or two people (the Emergency Physician and an assistant). Using the two-person technique, one person stabilizes the US probe over the vein and the other performs the procedure. Prepare the US probe as discussed below.
US PROBE PREPARATION A high frequency, 5 to 10 MHz, linear array US probe is typically used for US-guided vascular access. These US probes produce linear images and are ideal for visualization of superficial structures such as veins. Always use a sterile US probe cover and sterile US gel when performing central venous catheterization. Set up a sterile field on a bedside table. Open the US probe cover set onto the sterile field. Instruct an assistant to hold the US probe upright and place standard or sterile US gel on the footprint of the US probe (Figure 50-6A). Apply the sterile probe cover over the US probe (Figure 50-6B). Smooth all the air bubbles away from the footprint of the US probe to prevent imaging artifacts. Secure the cover with rubber bands to prevent it from sliding off the US probe (Figure 50-6C). Place the US probe on the sterile field (Figure 50-6D). Apply sterile US gel onto the cover over the probe footprint just before scanning.
US PROBE ORIENTATION
B FIGURE 50-5. Patient and US machine positioning for central venous access. A. Internal jugular vein access. B. Femoral vein access.
Orient the US probe. In the short axis approach, the marker on the US probe and the marker on the US machine screen should be aimed in the same direction (Figure 50-7). If the needle moves to the right side of the US probe, the needle also moves to the right on the US machine screen. This helps to accurately move the needle right to left while directing the needle towards the vein. This makes performing the procedure less complicated. In the long axis approach, it is important to know which way the probe marker is directed (cephalad or caudad) so that the Emergency Physician knows which side of the screen the needle will come from (i.e., the right or left of the image).
CHAPTER 50: Ultrasound-Guided Vascular Access
331
B
A
D
C
FIGURE 50-6. Preparing the US probe. A. An assistant holds the US probe upright and US gel has been applied. B. The sterile probe cover is applied. C. The sterile probe cover is secured with sterile rubber bands. D. The prepared US probe on a sterile field.
IDENTIFICATION OF VEINS Identify and verify the vein depth, direction, and patency prior to the procedure. To locate the internal jugular vein, place the US probe in the triangle formed by the two heads of sternocleidomastoid muscle and clavicle (Figure 50-8A). Scan from the apex of the triangle to the clavicle. Visualize the internal jugular vein, carotid artery, and thyroid gland (Figure 50-8B). The internal jugular vein is an irregular and oval-shaped structure lateral to the carotid artery (Figures 50-8B & C). Visualize the internal jugular vein and identify its widest diameter, the depth from the skin surface, and its relationship to the carotid artery. Instruct the patient to perform a Valsalva maneuver to increase venous flow and distend the internal jugular vein while observing the US machine screen to note the changes in the US appearance of the vein. To locate the common femoral vein, scan below the midpoint of inguinal ligament (Figure 50-9A). The common femoral
FIGURE 50-7. The US probe marker and the marker on the US machine screen are aimed in the same direction.
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SECTION 4: Vascular Procedures
A
A
B B FIGURE 50-9. Identification of the common femoral vein. A. Patient and US probe positioning. B. US image of the transverse or short axis view in B-mode (CFA, common femoral artery; CFV, common femoral vein).
C FIGURE 50-8. Identification of the internal jugular vein. A. Patient and US probe positioning. B. US image of the transverse or short axis view in B-mode. C. Short axis view in color Doppler mode. The large blue internal jugular vein is clearly visible adjacent to the red carotid artery (CA, carotid artery; IJV, internal jugular vein; SCM, sternocleidomastoid muscle).
artery should be clearly visible next to the common femoral vein (Figure 50-9B). The greater saphenous vein merges with the common femoral vein on the medial aspect. Visualize the common femoral vein and identify its widest diameter, the most superficial location, the depth from the skin surface, and a location that does not overlap with the common femoral artery.
Do not apply excessive pressure with the US probe when assessing the vein. Excessive pressure can collapse the vein and makes it difficult to identify. Verify that the identified vessel is compressible and truly a vein (Figure 50-2). The ability of the vein to be compressed distinguishes artery from vein, confirms the patency of the vein, and reduces the risk of cannulating a thrombosed vein. Do not assess compressibility in the long axis. The US probe may slide off the vein and be seen as the vein lumen disappearing and misinterpreting it as being compressible. Doppler US can be used to identify vascular structures. Color Doppler ensures the patency of blood vessels (Figure 50-8C). Spectral Doppler distinguishes blood flow patterns. Spectral Doppler demonstrates continuous venous flow in the internal jugular and femoral veins (Figure 50-10A). Triphasic pulsatile flow is seen on spectral Doppler in the carotid and femoral arteries (Figure 50-10B).
TECHNIQUES SHORT AXIS APPROACH TO CENTRAL VENOUS ACCESS The short axis approach allows visualization of the vein in cross section. This view is obtained by placing the US probe
CHAPTER 50: Ultrasound-Guided Vascular Access
A
333
B
FIGURE 50-10. Long axis US images of spectral Doppler waveforms. A. The internal jugular vein. B. The carotid artery.
perpendicular to the long axis of the vein. The vein appears ovalshaped in this view (Figures 50-1, 50-8B, & 50-9B). Place sterile US gel on the skin above the vein and on the footprint of the sterile US probe. Grasp the US probe with the nondominant hand and the needle with the dominant hand. As described previously, reidentify the vein and the optimal site of needle insertion. Adjust the US probe to center the target vein on the US machine screen. The midpoint of the US probe now becomes the reference point for needle insertion. Select the skin entry site to maximize the chances that the tip of the needle punctures the vein as well as intersect the US probe scan plane. The geometry of the Pythagorean Theorem (a2 + b2 = c2) can be used to assess the distance to insert the needle into the skin and away from the US probe (Figure 50-11). Measure the distance from the skin surface to the center of the vein. This distance is equal to the distance from the probe to where the needle punctures the skin at a 45° angle. For example, if the distance from the skin surface to the center of the vein is 1 cm, make the skin puncture 1 cm from the midpoint of the US probe along the trajectory of the vein (Figures 50-11A & B). Insert and advance the needle at a 45° angle. The vein will then be punctured after the
needle is inserted 1.4 cm. It is very useful to assess the distances using this method before venipuncture to avoid complications. If the vein is not punctured within the expected inserted needle length, the needle trajectory is not accurate and should be reassessed. It is important to understand that the US beam is very narrow and only 1 to 2 mm wide despite the US probe being approximately 1 cm wide. The needle will be visualized only when it is within this narrow beam width. The cross section of the needle in the short axis approach will be seen only when it crosses the US scan plane that is oriented perpendicular to the needle. The needle tip or shaft will appear as a hyperechoic dot within the vein (Figure 50-12A). It will be seen in association with either an acoustic shadow (black) or a reverberation or ring down artifact (white echoes) posterior to the needle (Figure 50-12B). Clean, prep, and anesthetize the skin after estimating the distance to the vein. Insert and advance the needle at a 45° angle (Figure 50-13). During the initial portion of the needle path, its location can only be identified by signs of it pushing through the tissue as soft tissue movement. This is because the needle has not yet crossed the US probe scan plane. Small, rapid, and in-line
FIGURE 50-11. The short axis approach needle insertion based on the Pythagorean theorem. A. The depth (a) equals the distance from the US probe (b) to insert the needle at a 45° angle. B. A sample calculation where a2 + b2 = c2.
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A FIGURE 50-14. Short axis US image demonstrating tenting of the anterior wall of the vein as it is penetrated by the needle.
collapse downward as it is being punctured and then return to normal after the wall is punctured. Visualize the hyperechoic needle tip within the lumen of the vein to confirm the needle entered the vein (Figure 50-12). A concurrent flash of blood will be seen in the syringe. Place the US probe back onto the sterile field. The remainder of the procedure is as described for the landmark technique of central venous access (Chapter 49).
B FIGURE 50-12. Short axis US image of a needle within a vein. A. The needle tip is visible as a hyperechoic dot inside the lumen. B. The reverberation or ring down artifact from the needle.
movements of the needle are helpful to locate the needle tip on the US image. Do not mistake the needle shaft for the needle tip. Always try to locate the needle tip by angling or fanning the US probe. As the needle contacts the anterior vein wall, it will tent or buckle the vein wall (Figure 50-14). The wall of the vein will first
FIGURE 50-13. The short axis approach for venous access.
LONG AXIS APPROACH TO CENTRAL VENOUS ACCESS The long axis approach targets the vein along its length in the longitudinal plane. Grasp the US probe in the nondominant hand and the needle with the dominant hand. Locate the target vein using the short axis approach. Verify it is compressible. Slowly rotate the US probe to visualize the vein in the long axis. The US probe should be positioned directly over the vein so that its long axis is parallel to the long axis of the vein (Figure 50-15). Adjust the US probe to visualize the vein at its greatest anteroposterior diameter. Insert the needle through the skin at approximately a 30° angle adjacent to one end of the US probe (Figures 50-15 & 50-16).
FIGURE 50-15. The long axis orientation and needle insertion.
CHAPTER 50: Ultrasound-Guided Vascular Access
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FIGURE 50-18. Patient and US machine positioning for upper extremity peripheral venous access.
Place the patient supine with their upper extremity abducted to expose the anteromedial aspect of the upper arm (Figure 50-18).
Place a tourniquet on the upper arm, just below the axilla, to distend the veins. Sit or stand at the patient’s bedside facing the patient. Position the US machine so that the screen is easily visible (Figure 50-18). To locate the veins and find the ideal venipuncture site, scan the entire upper arm from just below the tourniquet to the elbow. Identify the basilic vein along the medial aspect of the upper arm (Figure 50-19). Move the US probe slightly laterally to visualize the brachial vein adjacent to the brachial artery. Scanning further laterally will identify the cephalic vein. Peripheral veins collapse very easily. Minimize the pressure placed upon the skin surface with the US probe. Too much pressure can collapse these veins and make them difficult to identify. Identify the segment of vein that is widest in diameter, closest to the skin surface, and not adjacent to an artery. Verify that the vein is compressible and patent as described previously. Prepare the skin insertion site similar to peripheral IV placement. There is no need to follow any special precautions such as a sterile US probe cover. Apply a large transparent dressing (e.g., Tegaderm) onto the footprint of the linear array US probe. Make sure that no air bubbles are trapped between the transparent
FIGURE 50-17. Long axis US image of the needle shaft in the subcutaneous tissues and the tip inside the lumen of the vein.
FIGURE 50-19. Short axis US image of the basilic and brachial veins (BA, brachial artery; BAV, basilic vein; BV, brachial vein).
FIGURE 50-16. The long axis approach for venous access.
The needle should be in the plane that is in-line with the long axis of the US probe and in the exact same plane as the US beam. With this approach, it is crucial to keep the US probe steady and over the vein. Advance the needle. The needle tip and shaft will be visualized in real time as it travels through the subcutaneous tissues and into the lumen of the target vein (Figure 50-17). If it is not visualized in the US image, the needle plane and US probe scan plane are not aligned. Do not advance the needle any further. Withdraw the needle toward the skin and redirect it to align it with the US beam and the long axis of the vein.
PERIPHERAL VENOUS ACCESS
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SECTION 4: Vascular Procedures
A
FIGURE 50-21. Long axis US image of a cannulated peripheral vein. The catheter is visible inside the lumen of the vein.
B
ASSESSMENT Scan along the length of the cannulated vein in both the long axis view and the short axis view. Confirm the placement of the catheter within the lumen of the vein (Figure 50-21).
AFTERCARE No specific aftercare is required following the US guidance. The aftercare procedures are related to the central venous line (Chapter 49) and peripheral IV (Chapters 47 & 48) placement.
COMPLICATIONS FIGURE 50-20. US probe and needle insertion for upper extremity venous access. A. Long axis approach. B. Short axis approach.
dressing and the US probe. The transparent dressing keeps the field sterile and prevents contamination of the US probe with blood. Use a water-soluble lubricant (e.g., Surgilube) instead of US gel for scanning. Use a 2.5 to 3.0 in long catheter-over-the-needle for US-guided peripheral IV access. Standard length peripheral IV catheters are too short to reach or stay within the lumen of the vein. Identify the vein in either the long axis (Figure 50-20A) or the short axis (Figure 50-20B) using the methods described previously. Insert the catheter-over-the-needle under US guidance. Once the tip of the needle is within the lumen of the vein, advance the catheter into the vein (Figure 50-21). Put down the US probe. Withdraw the needle, attach IV tubing onto the hub of the catheter, and secure the catheter.
ARTERIAL ACCESS US guidance can be used to assist in obtaining an arterial blood gas and the placement of an arterial catheter. Identify the artery by its round shape, relatively thicket walls, noncompressibility, and pulsatile contractions. The procedure of cannulating an artery is the same as described above for a vein. Refer to Chapter 57 for the complete details regarding arterial puncture and cannulation.
Complications related to using US for vascular access are generally due to a poor technique or misinterpretation of images. An artery can be misinterpreted as a vein. There is no exposure to ionizing radiation. No increased risk of infections has been reported with the use of US when aseptic technique was followed. US guidance can be more time consuming when used for routine peripheral IV access. Its use may actually save time in the patient with difficult venous access. Using too short of a peripheral IV catheter can result in it being pulled out of the vein and the infusion solution extravasating. This can be prevented by using a longer (2 to 3 in) catheter-over-the-needle and/or inserting the catheter at a steeper angle to minimize the distance it travels in the subcutaneous tissues.
SUMMARY US-guided vascular access is widely supported in current clinical practice. It can be used for both central and peripheral IV access. US guidance has been shown to reduce failure rates and many of the complications associated with the traditional landmark technique. The benefits of US guidance include precise localization of the target vein, visualization of adjacent structures, identification of anatomic variations, avoidance of veins with thromboses, and real time visualization of venipuncture. Knowledge of the sonographic anatomy and basic US technology combined with hand–eye coordination are essential to perform this procedure. Understanding the principles discussed in this chapter will enhance the success rate of vascular access.
CHAPTER 51: Troubleshooting Indwelling Central Venous Lines
51
Troubleshooting Indwelling Central Venous Lines
is discouraged. Manipulation of a dialysis line should only be undertaken in a true emergency or if the line is malfunctioning and is needed for hemodialysis.
James J. McCarthy
INTRODUCTION Indwelling central venous lines are an essential part of the care of both the acutely and chronically ill patients. These patients may require implanted venous access devices due to their poor peripheral venous access or for long-term intravenous therapies. When an indwelling central venous line is malfunctioning, the Emergency Physician must act quickly and thoughtfully to diagnose and correct the malfunction without further damaging the device. Understanding the different etiologies and a thorough assessment are critical to the successful management of a central venous catheter malfunction.
ANATOMY AND PATHOPHYSIOLOGY Indwelling central venous catheters allow access to the central venous circulation from a peripheral site. This access to the central circulation is via the end of a partially implanted catheter that protrudes from the body or through the skin into a subcutaneous reservoir of a fully implanted catheter.1,2 The proximal tip of the central venous line will typically reside in either the superior vena cava, the inferior vena cava (less commonly), or the right atrium. Indwelling central venous access devices can malfunction for a variety of reasons. The two most common types of vascular catheter complications are thrombotic occlusions and infections.3 The etiology of the malfunction can be divided into two main categories: external to the catheter and internal to the catheter. External malfunctions are for the most part mechanical malfunctions. Examples include catheter migration, the catheter tip abutting a vessel wall, a mural thrombus, and kinked catheters. Internal malfunctions can be further divided into thrombotic (e.g., intraluminal thrombus, fibrin sheath, and fibrin tail) and nonthrombotic (e.g., drug/ drug precipitate, insoluble salts, lipid precipitate, and drug/solution precipitate).3–5 Phenytoin and diazepam cannot be given through silicone indwelling lines as they can crystallize and permanently obstruct the catheter lumen.4 Calcium and phosphate can form an insoluble precipitate within the catheter lumen. Infused lipids can form waxy casts within the catheter lumen.
INDICATIONS Any catheter that cannot be easily flushed or aspirated requires further investigation. If peripheral venous access is readily available, and the patient is not acutely ill due to catheter sepsis or central venous thrombosis, catheter troubleshooting may be deferred to the Primary Care Provider. It is important to consider that delaying troubleshooting may make management more difficult and therefore necessitate line replacement. However, the Emergency Physician will have to address the problem if emergent or urgent access to the patient’s central vascular system is required.
CONTRAINDICATIONS Any device that is obviously displaced from the central circulation is not salvageable and should not be used. Dislodging a clot or septic thrombus from a catheter tip can lead to a fatal pulmonary embolism. Catheter manipulation should be avoided if signs of sepsis or central venous thrombosis are present.6 The use of indwelling dialysis lines for purposes other than dialysis
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EQUIPMENT • • • • • • • • • • • •
Povidone iodine or chlorhexidine solution Sterile alcohol prep pads Thrombolytic agent Syringes, 5 mL and 10 mL 18 gauge needles Noncoring (Huber) needle 70% ethanol solution 0.1 N hydrochloric acid (HCl) solution Sterile saline Heparinized saline flush solution (100 U/mL) Sterile gauze squares Sterile gloves
Repair kits are available to repair some externally damaged partially implanted catheters. The kits avoid the need to remove the device and implant a new catheter. If the external tubing of the device is damaged, apply a smooth catheter clamp proximal to the damaged area and arrange to have the device repaired. The use of these kits is beyond the scope of this chapter.
THROMBOLYTIC AGENTS The use of a specific thrombolytic agent is institution-specific and physician-specific. Streptokinase, recombinant tissue plasminogen activator (t-PA), Reteplase, and urokinase have all been successfully used to dissolve a clot within a central venous catheter.4,7–12 Volumes and doses of the drugs differ significantly and careful attention should be paid to the medication administration. Urokinase and recombinant tissue plasminogen activator are most commonly used. Streptokinase is more likely to lead to a hypersensitivity reaction, especially if the patient has prior exposure to it, and is therefore not recommended. Urokinase is the thrombolytic agent used by most institutions because it is much less expensive than t-PA. Urokinase may be purchased in concentrations of 5000 U/mL and 250,000 U/5 mL (50,000 U/mL). The concentration of 5000 U/mL is used for dissolving a clot within a catheter. Some institutions prefer to use t-PA for this process. The Pharmacist dilutes a 50 mg vial of t-PA with 50 mL of sterile water to produce 25 syringes containing 2 mg of t-PA in 2 mL (1 mg/mL). The syringes of t-PA are then frozen until needed. It is also available from the manufacturer in 2 mg single use vials. Standard dosing for catheter obstructions is 1 mL of urokinase (5000 U/mL), 2 mL of t-PA (1 mg/ml), or 0.4 units of Reteplase.15
PATIENT PREPARATION Discuss the procedure with the patient and/or their representative. Most patients with indwelling central venous access devices are very familiar with their use and idiosyncrasies. The patient will often be able to tell the Emergency Physician if the line has had problems in the past and the method used to correct the problem. Some patients will be able to suggest postural changes (e.g., raising an arm or lying in the Trendelenburg position) that will help the catheter function better. Obtain a posteroanterior and lateral chest radiograph to confirm that the tip of the catheter is in a proper location.
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SECTION 4: Vascular Procedures Catheter occluded • CXR to verify catheter tip position • May infuse with caution if able to inject but not aspirate
Change patient position • Raise arms • Deep breath • Trendelenburg or recumbent • Cough
No precipitate
Still occluded
Precipitate seen or suspected
Attempt to aspirate clot of large-bore partially implanted catheter with a syringe connected directly to the catheter Luer hub
Waxy • TPN • Intralipids
Particulate or crystalline • Medications • Minerals (calcium & phosphate)
Urokinase, t-PA or reteplase injection ⫻3
EtOH ⫻ 1
HCI ⫻ 3
HCI ⫻ 3
EtOH ⫻ 1
Contrast dye study
No clot or cannot infuse contrast material
HCI ⫻ 3
EtOH ⫻ 1
Clot present Urokinase, t-PA or reteplase injection ⫻3 Urokinase or t-PA infusion, may repeat dye study & infusion once
Contact consultant, catheter will probably need to be replaced
FIGURE 51-1. An algorithmic approach to the occluded central venous catheter. Continue to work down the protocol until the occlusion is resolved (CXR, chest radiograph; EtOH, 70% ethanol in water; HCl, 0.1 normal hydrochloric acid solution; TPN, total parenteral nutrition).
The chest radiograph is a good screening tool that allows the Emergency Physician to often diagnose catheter complications. A malpositioned catheter or one with the tip abutting the vessel wall must be removed and replaced. A catheter whose flow changes with patient arm position may be subject to the “pinch-off ” phenomenon. This may be visible as a kinking of the catheter as it passes between the clavicle and first rib. A series of chest radiographs with the arm at the patient’s side and elevated may reveal the kinking or pinching-off of the catheter. These catheters require removal. A catheter may migrate intravascularly so that it is within the contralateral subclavian vein. An Interventional Radiologist may be able to insert a wire or snare into the femoral vein to grasp and reposition the catheter. Arrhythmias associated with a catheter tip positioned within the heart require the catheter to be removed and a new one inserted. The distal catheter can curve upward so that it lies within the jugular vein. An Interventional Radiologist may be able to reposition it. Otherwise, it must be removed and replaced. Any manipulation, injection, or aspiration of a central venous line must be done using strict aseptic techniques. Clean any dirt
and debris from the distal port of a partially implanted device or the skin overlying the reservoir of a fully implanted device. Apply povidone iodine or chlorhexidine and allow it to dry. Wipe off the iodine (if used) with a sterile alcohol prep pad. This process must be performed every time a needle is inserted into a central venous access device.
TECHNIQUES An algorithmic approach to the occluded indwelling central venous catheter is summarized in Figure 51-1.9,14 The key principle is that forced irrigation of the catheter, especially with a 1 mL syringe, is never performed as the catheter may rupture. A catheter that flushes easily but cannot be aspirated may have a fibrin sheath around the catheter tip forming a one-way valve. The tip may also be lodged against the wall of the superior vena cava or the right atrium. Repositioning the patient may alleviate the problem. The catheter may be cautiously used for an infusion if there are no signs of infection (e.g., new heart murmur, fever, erythema, or discharge at the catheter or subcutaneous reservoir
CHAPTER 51: Troubleshooting Indwelling Central Venous Lines
site) and the catheter tip is in good position. Refer the patient to their Primary Care Provider or a consultant for follow-up of the malfunction. The problem is more serious if the catheter does not easily flush. Attempt to obtain peripheral intravenous access while attempting to correct the problem with the central venous catheter. If there are no signs of infection, and the catheter is not ruptured or malpositioned, the Emergency Physician must decide if a prolonged effort at resolving the occlusion is necessary. If so, proceed as described below and in Figure 51-1.
PARTIALLY IMPLANTED CATHETERS A clot or small amount of precipitate within the partially implanted catheter may be able to be aspirated if the catheter bore is large enough to permit passage. Remove the Luer-lock cap from the catheter. Connect a 10 mL syringe with 2 to 3 mL of sterile saline directly to the occluded port’s Luer adapter. Any clot large enough to occlude the catheter will not pass through a needle. Apply negative pressure to the syringe. The catheter is probably occluded by a clot or a precipitate if the obstruction cannot be aspirated. Remove the syringe and attach a new Luer-lock cap. If a precipitate is seen in the catheter aspirate, determine if it is waxy or solid. Waxy precipitates are due to the lipid component of parenteral nutrition fluids. Waxy precipitates may be dissolved with a solution of 70% ethanol in water. Inject 1 to 2 mL of this alcohol– water solution and allow it to dwell in the catheter for 1 hour. Aspirate the catheter to determine patency. If still occluded, inject 1 to 2 mL of 0.1 N hydrochloric acid solution. Allow the solution to dwell in the catheter for 20 minutes. Aspirate the catheter to determine patency. Attempt to infuse 0.1 N hydrochloric acid solution two more times. The next step is to infuse a thrombolytic agent, as described below, or to replace the catheter. Solid precipitates are due to precipitation of medications or minerals. Dilute 0.1 hydrochloric acid solution may be used to dissolve precipitated calcium and phosphate crystals. Infuse 1 to 2 mL of 0.1 N HCl and allow it to dwell in the catheter 20 minutes. Aspirate the catheter to determine patency. The process may be repeated up to three times. If still occluded, inject 1 to 2 mL of 70% ethanol in water and allow it to dwell in the catheter for 1 hour. Aspirate the catheter to determine patency. The next step is to inject a thrombolytic agent, as described below, or to replace the catheter. If no precipitate is present, or if efforts to clear the precipitate fail, a clot may be present within the catheter lumen. Clots probably form to some extent in the majority of implanted central venous catheters. The clots may obstruct the catheter lumen.13 Thrombosis of the central veins, superior vena cava, or right atrium may also occur. Suspect a major vein thrombosis if there is swelling, pain, or edema of anatomic structures that are drained by the cannulated vein(s). Small clots may be dissolved by a bolus or infusion of a thrombolytic agent. Inject 1 mL of urokinase (5000 U/mL), 2 mL of t-PA (1 mg/mL), or 0.4 units of Reteplase into the catheter. Allow the solution to dwell in the catheter for 30 minutes. Aspirate the catheter to determine patency. This process may be repeated up to three times. For catheters with multiple occluded ports, the medication dosing should remain the same but divided into equal doses between the ports. If still occluded, inject 2 mL of intravenous contrast dye under fluoroscopy or inject the dye and obtain a radiograph. If no clot is present or if the contrast material will not infuse, attempt to clear the catheter with hydrochloric acid solution (up to three times) and 70% ethanol in water. If a clot is present within the catheter, a continuous thrombolytic infusion may be considered. The infusion should occur through
339
an intravenous line equipped with a 0.22 micron or 0.45 micron filter. A urokinase infusion may be begun over a 24-hour period. Administer the urokinase at a dose of 200 U/kg-hr mixed to run at a rate of at least 20 mL/h.8,9 A continuous t-PA infusion may also be started. Use 2 mg/20 mL as a low dose for ports, 4 mg/20 mL as a high dose for ports, or 5 mg/50 mL as a high dose for tunneled catheters. Set the t-PA infusion rate at 10 mL/h for low and high doses for ports or 20 mL/h for high dose tunneled catheters. Thrombolytic infusions should be undertaken in consultation with the patient’s Primary Care Provider as the patient will require hospital admission. Consider consulting an Interventional Radiologist if these methods do not successfully clear the catheter or if a thrombolytic infusion is contraindicated. They can perform percutaneous fibrin sheath stripping, exchange over a wire, or removal and replacement of the malfunctioning catheter. Alternatively, the Emergency Physician may place a new central venous catheter at another site if the patient requires immediate vascular access.
FULLY IMPLANTED CATHETERS The procedure is the same for a fully implanted central venous access device with one exception. The subcutaneous reservoir will not be able to be initially cleared by aspiration. Any clot or precipitates large enough to occlude a catheter will not pass through a noncoring (Huber) needle. Always use a noncoring (Huber) needle when aspirating or injecting through a fully implanted catheter.
AFTERCARE Indwelling central venous lines must be flushed with saline, followed by the appropriate heparin solution if necessary, after clearing the obstruction. Refer to Chapter 49 for the complete details. Patients given thrombolytics must be assessed for bleeding at the catheter site and elsewhere prior to discharge, if they do not require hospital admission. The success rate for thrombolytics restoring catheter patency are greater than 80%.16,17 Patients receiving prolonged thrombolytic infusions should be admitted for the infusion and for monitoring of potential bleeding complications. Patients and their care providers must be made aware of any catheter malfunctions and the attempts made at restoring catheter patency.
COMPLICATIONS The complications associated with attempts to de-occlude a catheter include catheter rupture, disconnection of the catheter from any implanted reservoir, hemorrhage, and contamination of the catheter with subsequent infection. No major bleeding episodes or deaths have been associated with intracatheter thrombolysis.15–17 Assessment for these complications is discussed in Chapter 49.
SUMMARY In the course of their treatment, a number of patients with indwelling central venous access devices will present to the Emergency Department with malfunctioning catheters. Familiarity with the strategies for diagnosing and correcting the catheter dysfunction will enable the Emergency Physician to restore the function of some, but not all, indwelling lines. Early consultation with the patient’s Primary Care Provider, Vascular Surgeon, or Interventional Radiologist is essential if the procedures outlined do not promptly restore the catheter’s function.
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52
Accessing Indwelling Central Venous Lines Lisa Freeman Grossheim
INTRODUCTION Venous access for medication administration, nutritional support, hemodialysis, and blood sampling is essential for the management of many chronic diseases. A variety of indwelling central venous access devices have been developed to avoid repeated venipunctures and permit direct access to the central circulation. These devices may be partially or completely implanted under the patient’s skin. The Emergency Physician must be able to access these devices to administer medications and withdraw blood samples without damaging the device or causing it to clot off. The necessary procedures for successfully accessing indwelling central venous lines are described in this chapter.
ANATOMY AND PATHOPHYSIOLOGY Indwelling central venous lines allow access to the central venous circulation from a peripheral site.1,2 This is accomplished through either the end of a partially implanted catheter or through the skin into a subcutaneous reservoir of a fully implanted catheter (Figure 52-1). The proximal tip of the central venous line may lie in the superior vena cava or in the right atrium. Catheters designed for right atrial placement are made of softer and more pliable material than are catheters used for short-term transcutaneous central
Superior vena cava
venous access. These catheters are unlikely to erode through or perforate the thin right atrial wall. The internal jugular, subclavian, and femoral veins can all be utilized as a route for a central venous line to access the superior vena cava or right atrium. The subclavian veins are most commonly used to maximize patient comfort and mobility. When the line is initially inserted, the vein is punctured transcutaneously, the catheter is inserted into the vein, and its distal end is tunneled under the skin. If the line is partially implanted, the distal end of the catheter is brought external to the skin through a small puncture (Figure 52-1A). If the line is fully implanted, its distal end is connected to a subcutaneous reservoir that is placed in a pocket dissected under the skin of the chest wall (Figure 52-1B).
PARTIALLY IMPLANTED CATHETERS Partially implanted central venous catheters (Figures 52-1A & 52-2) are those whose distal end emerges from the skin via a subcutaneous tunnel.3 This tunnel helps prevent the spread of skin flora along the outside of the catheter and toward the central circulation. Most partially implanted catheters use a subcutaneous Dacron cuff to further insulate the proximal catheter from skin flora and help anchor the catheter in place.4 A variety of models are in use, including the Broviac,5 Hickman,6 and Groshong7 catheters. All are available in single-lumen or multiple-lumen versions. Broviac and Hickman catheters must be flushed with heparin solution twice weekly. The Groshong catheter is unique in that it has a slit valve at its proximal end that prevents blood from reentering the catheter once it has been flushed (Figure 52-3). Groshong catheters need only a weekly saline flush to prevent clot formation.
Subcutaneous reservoir
Right subclavian vein Vein entry site Cephalic vein
B A
Dacron cuff (under skin) Skin exit site
Right atrium FIGURE 52-1. Indwelling central venous lines. A. The partially implanted central venous line. The distal end of the line emerges from the chest wall. Contamination of the implanted portion is prevented by a subcutaneous tunnel and a Dacron cuff around the catheter. B. The fully implanted central venous line. The catheter is connected to a reservoir that is contained in a subcutaneous pocket.
CHAPTER 52: Accessing Indwelling Central Venous Lines
341
Female luer adapter Catheter lumen diameter & volume printed on luer adapter sleeve Clamp Protective clamping sleeve
Dacron cuff Strengthening sheath (Broviac catheters only) FIGURE 52-4. The fully implanted central venous catheter. The reservoir lies in the subcutaneous tissue and is anchored with sutures to keep the diaphragm facing the skin surface.
FIGURE 52-2. The partially implanted central venous catheter. A single-lumen (Hickman or Broviac) line is shown schematically. The Dacron cuff lies in the subcutaneous tissue just proximal to the skin entry site. The catheter tip lies in either the proximal superior vena cava or the right atrium.
The Hemocath or Permacath is the largest bore of the right atrial catheters. It is manufactured by Quinton and is used for hemodialysis, plasmapheresis, long-term nutritional support, and analgesia. These catheters are typically flushed during dialysis, but otherwise should be flushed three times per week with heparinized saline.
FULLY IMPLANTED CATHETERS Fully implanted central venous catheters are those that are entirely embedded and do not exit the skin (Figures 52-4 & 52-5). The
catheter’s distal end is attached to a subcutaneously implanted reservoir.4 Various catheters, including Hickman and Groshong catheters, can be attached to a subcutaneous reservoir. Most fully implanted central venous access systems are known by the brand names Port-A-Cath and Infusaport. Most manufacturers recommend that these catheters must be flushed with a heparin solution monthly when not in use.7 However, there are some data that suggest that flushing of the port system can be done every 3 months without any increase in complications.7 The reservoir’s infusion port is covered with a self-sealing silicone rubber membrane (Figures 52-4 & 52-5). Specially designed noncoring or Huber
Right angle Huber needle
Clamp
Stabilizing suture
FIGURE 52-3. The Groshong central venous catheter tip. Detail of the Groshong three-position slit valve that prevents venous blood from passively entering the catheter when it is not in use. A. The closed or resting position of the slit valve. B. The valve opens outward from positive pressure when the catheter is flushed or infused. C. The valve opens inward from negative pressure when the catheter is aspirated.
Catheter
Self-sealing membrane
Fluid flow FIGURE 52-5. Accessing the fully implanted central venous catheter system. The reservoir is stabilized between the fingers of the Emergency Physician’s nondominant hand as a noncoring (Huber) needle is used to penetrate the skin and reservoir.
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needles must be used when accessing the subcutaneous reservoir to avoid permanently damaging the self-sealing membrane.
PERIPHERALLY INSERTED CENTRAL CATHETERS Peripherally inserted central catheters are also known as PICC lines. They are inserted into the brachial, cephalic, or antecubital vein of the upper extremity and advanced into the subclavian vein. The greatest drawback for the use of PICC lines is the 50% risk of catheter-related thrombosis. PICC lines are made of either silicone or polyurethane. They are 50 to 60 cm long and have an outside diameter of 2 to 7 French, with the 5 French being most commonly used. They are available in both single-lumen and double-lumen versions. Some PICC catheters are equipped with a Dacron cuff similar to the Broviac and Hickman catheters.
PERCUTANEOUS CENTRAL VENOUS CATHETER A device similar to the PICC is known as the percutaneous central venous catheter (PCVC). This catheter is often used in neonates in the neonatal intensive care unit and not in the Emergency Department. It is available in three sizes (1.1, 1.9, and 2.8 French). The 2.8 French size is used more often because the smaller sizes tend to become occluded with a thrombus. This device is only mentioned for completeness.
INDICATIONS PATIENTS REQUIRING INDWELLING CENTRAL VENOUS LINES Patients of all ages and with a variety of diagnoses may present with an indwelling central venous line. Some examples of such presentations are chronic painful conditions requiring parenteral analgesia (e.g., sickle cell disease), chronic infections requiring long-term parenteral antibiotics (e.g., endocarditis, osteomyelitis), the need for prolonged hyperalimentation, patients with difficult peripheral intravenous access, and cancer patients required chemotherapy and blood sampling. Any patient who will require several weeks of repeated intravenous blood sampling and/or drug administration is a candidate for an indwelling central venous line.
infection. An inability to dialyze the patient will lead to significant morbidity and mortality. There are a finite number of veins available for dialysis access.
EQUIPMENT • • • • • • • • • • • • • • • • •
Povidone iodine or chlorhexidine solution Sterile gauze, 4 × 4 squares 10 mL syringes 20 gauge needles Sterile saline, 0.9% Heparinized saline flush (100 and 1000 U/mL) Adhesive tape Luer-lock caps Blood collection tubes Infusion set Any intravenous fluids or medications to be injected Huber needle, noncoring right angle or straight angle Topical anesthetic (EMLA cream, ethynyl chloride spray, or ice) Injectable anesthetic without epinephrine, 1% lidocaine Sterile alcohol prep pads Sterile gloves Sterile drapes
PATIENT PREPARATION Discuss the necessary procedure with the patient and/or their representative. Obtain an informed consent for accessing the device. Patients with indwelling central venous lines are usually very familiar with their care and use. They can often advise the Emergency Physician on the correct procedure, the appropriate flush solution, and any anatomic manipulations necessary to optimize flow through the line (e.g., raising the arms, turning the head, etc.). Aseptic technique is required at all times when accessing indwelling central venous catheters.
TECHNIQUES
ACCESS OF INDWELLING CENTRAL VENOUS LINES
PARTIALLY IMPLANTED CATHETERS
Fully or partially implanted central venous access devices may be accessed routinely when phlebotomy is required, medications must be administered, or intravenous fluids must be administered.
Accessing a partially implanted central venous catheter is simple and similar to accessing a heparin-locked peripheral intravenous catheter.7,10 Remove any adhesive tape and gauze wrapped around the distal end of the lumen to be accessed. Fasten the catheter clamp on the desired lumen (Figure 52-2). Clean the catheter cap and Luer adapter with povidone iodine or chlorhexidine solution and allow it to dry. The technique for accessing the catheter will vary depending on whether blood sampling with or without a subsequent infusion is required. Both techniques are described below.
CONTRAINDICATIONS Do not access an indwelling central venous device if peripheral intravenous access can be obtained. The use of bedside ultrasound may facilitate peripheral intravenous access and avoid accessing the indwelling device. Fully implanted devices should not be accessed through infected skin. Partially implanted catheters known or suspected to be infected should be used cautiously, as they may be a source of septic emboli, although it is sometimes possible to treat catheter sepsis without removing the device.8,9 Phenytoin and diazepam cannot be given via silicone indwelling central venous lines as they can crystallize and permanently obstruct the catheter lumen.10 Devices used for hemodialysis should be accessed only in a true emergency and if no other method of venous access can be readily obtained. This guideline is intended to prevent loss of the patient’s dialysis access due to device damage, clotting, or an
BLOOD SAMPLING FROM PARTIALLY IMPLANTED CATHETERS Blood samples may be withdrawn through the catheter cap using a 20 gauge hypodermic needle attached to a 10 mL syringe if blood is to be sampled without beginning an infusion. Insert the needle through the Luer cap. Open the catheter clamp. Withdraw 5 mL of blood from the catheter. Discard the blood sample, needle, and syringe. This blood sample is diluted by the catheter contents (i.e., saline or heparinized saline) and does not truly represent the circulating blood. This step is essential when accessing dialysis catheters
CHAPTER 52: Accessing Indwelling Central Venous Lines
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as they contain a dose of concentrated heparin (1000 U/mL). If unable to aspirate blood, gently flush the catheter with 2 to 3 mL of sterile saline. Avoid using a syringe smaller than 5 mL to inject as pressure high enough to damage the catheter can be generated. Refer to Chapter 51 for troubleshooting instructions if the catheter does not flush easily. Withdraw the required blood samples using a new needle and syringe. Transfer the blood samples into collection tubes for the laboratory. The catheter must now be flushed to prevent it from clotting off. Flush the catheter with the appropriate solution in a 10 mL syringe armed with a 20 gauge needle. Inject 3 to 5 mL of heparinized saline (100 U/mL) into Broviac and Hickman catheters. Inject 5 mL of normal saline into a Groshong catheter. Inject dialysis catheters with the volume printed on the catheter, usually ≤2 mL, of heparinized saline (1000 U/mL). Wipe off the cap with an alcohol pad. Secure the free end of the catheter. Tape the catheter to the patient’s chest wall to prevent accidental traction on the catheter. Evaluate the skin puncture site. Reapply a dressing over the skin puncture site if necessary.
clamp. Remove and discard the syringe with the original blood sample. Apply a new syringe, open the catheter clamp, and withdraw the blood sample. Close the catheter clamp. Remove the syringe. Continue this sequence of events until all required blood samples are obtained. It is imperative to make sure that the catheter is clamped when the cap or syringe is removed to prevent an air embolism. Securely attach primed intravenous tubing to the hub of the catheter, open the catheter clamp, and begin the infusion. Clamp the catheter lumen when terminating the infusion or if no infusion is to be started. Remove the intravenous tubing or the syringe from the catheter. Attach a syringe containing the appropriate flush solution, open the catheter clamp, and flush the catheter. Close the catheter clamp. Remove the syringe. Apply a new sterile cap onto the hub of the catheter. Never use “needle-less” caps, as they are a potential source of air emboli. Open the catheter clamp to prevent catheter damage from long-term clamping. Secure the catheter to the patient’s chest wall.
BLOOD SAMPLING AND INFUSION THROUGH PARTIALLY IMPLANTED CATHETERS
A noncoring Huber-type needle must be used to access subcutaneous injection ports (Figures 52-5 & 52-6). A small-gauge standard hypodermic needle can be used only in a dire emergency if a noncoring needle is not available. The diaphragm covering the injection reservoir can be damaged by a standard hypodermic needle, leading to subcutaneous hemorrhage and necessitating surgical replacement of the implanted device. Clean and prep the skin overlying the injection port with povidone iodine or chlorhexidine solution and allow it to dry.
The Luer catheter cap can be removed entirely and the catheter lumen accessed directly with a Leur-hub syringe if an infusion is to be subsequently started. Ensure that the catheter clamp is securely closed. Remove the cap from the catheter. Attach a 10 mL syringe to the hub of the catheter. Open the catheter clamp. Withdraw 5 mL of blood into the syringe. Close the catheter
FULLY IMPLANTED CATHETERS
B
A
FIGURE 52-6. The Huber needle. A. Photo of a complete right-angle Huber needle set, including the extension tubing and clamp. B. Photo showing the right-angle Huber needle compared with a standard hypodermic needle. C. Drawing showing the key difference between a standard hypodermic needle and the Huber needle. The hypodermic needle tip can cut a cylindrical core of subcutaneous tissue and the diaphragm sealing the subcutaneous reservoir. The Huber needle pushes the subcutaneous tissue and the diaphragm material aside without removing any of it.
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TABLE 52-1 Volumes and Concentrations of Heparin Flushes for Pediatric Indwelling Devices Children < 6 months old Children > 6 months old Partially implanted 3 mL heparin (10 U/mL) 5 mL heparin (100 U/mL) device PICC line 3 mL heparin (10 U/mL) 5 mL heparin (100 U/mL) Fully implanted 3 mL heparin (10 U/mL) 5 mL heparin (100 U/mL) device
The application of a topical or injectable anesthetic over the reservoir is optional but greatly appreciated by the patient. Remove the iodine solution (if used) with an alcohol swab. Flush the Huber needle and extension tubing with normal saline using a 10 mL syringe. Leave the syringe attached. Locate the center of the selfsealing membrane (diaphragm). Stabilize the reservoir with the nondominant hand (Figure 52-5). Slowly and steadily insert the needle through the skin and into the reservoir (Figure 52-5). Stop advancing the needle when it touches the far wall of the device. Gently flush 2 to 3 mL of saline through the needle. Refer to Chapter 51 for troubleshooting instructions if the catheter does not flush easily. If the catheter can be flushed easily, secure the Huber needle in place by stabilizing it with gauze squares and tape. Withdraw 5 to 10 mL of blood. Close the clamp on the extension tubing (Figure 52-5). Remove and discard the syringe. Attach a new syringe, open the clamp, and withdraw the required blood samples. Clamp the extension tubing and remove the syringe. If an infusion is to be started, attach the primed intravenous tubing and begin the infusion. If no infusion is desired or when discontinuing an infusion, clamp the extension tubing and disconnect the intravenous tubing. Attach a 5 or 10 mL syringe containing heparinized saline (100 to 200 U/mL) to the Huber needle extension tubing. Open the clamp and flush the device with 3 to 5 mL of heparinized saline. Use only saline if a Groshong catheter is attached to the reservoir. Remove the Huber needle from the skin. Control any skin bleeding with direct pressure. Apply a sterile dressing.
PEDIATRIC CONSIDERATIONS The management of pediatric indwelling devices is similar to those in adults with a few noted exceptions. The catheters, reservoirs, and tubing are often smaller than those used in adults or adolescents. The volumes and concentrations of heparin flushes differ in these smaller catheters (Table 52-1). The external portion of partially implanted devices and PICC lines must be secured with a dressing so that the child does not pull it out.
ASSESSMENT Assessment of line function after accessing a central venous access device will not occur until the next access attempt. This procedure is described above. Troubleshooting nonfunctioning indwelling central venous lines is discussed in Chapter 51.
AFTERCARE Secure the partially implanted catheter to the skin with tape so that the tubing will not get caught on the patient’s clothing. The patient should be given a written record of how the access device was used and flushed in the Emergency Department to convey to their Primary Care Physician should problems with the line become evident at a later time. Patients must regularly assess their indwelling access sites for signs of infection (i.e., erythema, pain, purulent
discharge, or serous discharge). Instruct the patient to immediately contact their Primary Care Provider or return to the Emergency Department if they develop a fever or other signs of an infection.
COMPLICATIONS The most important elements after accessing indwelling lines are to not allow the central venous line to clot off and not to contaminate the line. Strict adherence to the procedures described above will minimize the chances of these problems occurring. Complications associated with the catheter include right atrial thromboses, right atrial erosion with pericardial tamponade (rare with implanted lines), catheter-related infections, and pulmonary embolism.7,9,11,12 Fully implanted catheters may become disconnected from the subcutaneous reservoir or may leak into the subcutaneous tissue due to diaphragm failure. Any hematoma formation near the reservoir must be assessed promptly to prevent major hemorrhage. Infection and line sepsis can be prevented using strict sterile technique. An air embolism should be suspected if the patient becomes confused, hypotensive, and/or tachycardic while accessing the central venous access device. This complication is 100% preventable by ensuring that the catheter tubing is clamped closed whenever the end of the tubing is without a cap. Immediately place the patient in the Trendelenburg position and on their left side (i.e., left lateral decubitus position). This will hopefully cause any air emboli to collect in the apex of the right ventricle and not enter the pulmonary artery. Repair kits are available for damaged partially implanted catheters. These can serve to avoid the need to remove the device and implant a new catheter. If the external tubing of the partially implanted catheter is damaged, apply a smooth catheter clamp proximal to the damaged area and arrange to have the device repaired. Instructions for the use of these kits are beyond the scope of this chapter.
SUMMARY The Emergency Physician will encounter many patients with indwelling central venous lines. Careful adherence to sterile technique as well as proper blood sampling and infusion techniques will allow access for phlebotomy, medication administration, and fluid administration while preserving the indwelling line for future use.
53
Pulmonary Artery (Swan-Ganz) Catheterization Pratik Doshi
INTRODUCTION The routine clinical catheterization of the pulmonary artery was made possible by the pioneering work of H.J.C. Swan and William Ganz. Together they developed the soft, balloon-tipped, flowdirected pulmonary artery catheter (PAC) that bears their names.1 Prior to the work of Swan and Ganz, pulmonary artery catheterization was performed using a stiff catheter that required fluoroscopic guidance and was associated with a high complication rate. The Swan-Ganz PAC allows reliable and continuous measurement of hemodynamic parameters to be performed safely, even in critically ill patients.2–4 While complications are uncommon, they can
CHAPTER 53: Pulmonary Artery (Swan-Ganz) Catheterization
occur. The optimal application of the PAC, both its insertion and interpretation of the data, requires appropriate training and skill.5–7 This chapter concentrates on the technique of PAC insertion. Obtaining central venous access is a necessary prerequisite for this technique and is discussed in Chapter 49. A detailed discussion of the interpretation of the abundant variety of data that the PAC may provide is beyond the scope of this chapter.8 The interpretation of data is discussed primarily as it concerns PAC insertion and associated complications.
Right internal jugular vein
Right subclavian vein
ANATOMY AND PATHOPHYSIOLOGY The PAC is advanced into the right atrium from a venous access site in the neck, chest, upper extremity, or lower extremity. The balloon near the tip of the catheter is inflated during its insertion. The balloon follows the flow of blood through the right heart—from the right atrium through the tricuspid valve into the right ventricle, then up the right ventricular outflow tract through the pulmonic valve into the pulmonary artery, and from there into a branch of the pulmonary artery (Figure 53-1). When the PAC is correctly positioned, inflating the balloon near its tip will occlude the forward blood flow to that arterial segment (Figure 53-2). The lumen opening at the tip of the PAC will therefore measure the downstream pressure in that vessel, rather than pulmonary artery pressure. Because the pulmonary circulation has no valves, the pressure that the PAC tip measures beyond the inflated balloon is equal to the pressure in the pulmonary capillaries. This pressure is, in turn, equal to the pressures in the pulmonary veins and the left atrium. During diastole, when the mitral valve is open, this pressure is equal to the left ventricular diastolic pressure. The left ventricular end-diastolic pressure is a very important parameter because it is the best clinical indicator of preload. Thus, measurement of the pulmonary capillary wedge pressure (or pulmonary artery occlusion pressure, as it is sometimes called) provides an excellent assessment of left ventricular filling without the need to catheterize the left side of the heart.
Right pulmonary artery
Superior vena cava
Pulmonary artery
Pulmonary artery catheter FIGURE 53-1. Cardiac anatomy as it pertains to pulmonary artery catheter insertion. The PAC enters the right atrium from the superior vena cava, crosses the tricuspid valve into the right ventricle, and then crosses the pulmonic valve into the pulmonary artery. The catheter tip lies in a branch of the right pulmonary artery.
The PAC may also be used to measure cardiac output using the thermodilution method. The tip of the PAC has a temperaturesensitive probe. When a given volume of cold saline is injected into the right atrial port of the PAC, it cools the temperature of the blood flowing past the catheter tip. If the cardiac output is high, the cold saline is mixed with and carried along by a larger flow of blood so that the temperature change detected at the PAC tip is smaller and
Left pulmonary artery
Branch of right pulmonary artery
Pulmonary capillaries
Main pulmonary artery
Pulmonary artery catheter from right ventricle Pulmonary veins
Left atrium
Mitral valve Left ventricle
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FIGURE 53-2. Diagram of the principle underlying pulmonary capillary wedge pressure. Balloon inflation blocks transmission of the forward pulmonary artery pressure to the tip of the catheter. The catheter tip therefore measures the downstream pressure of the pulmonary circulation. Because the pulmonary circulation has no valves, the pressure measured at the catheter tip is equal to the pressure in the left ventricle when the mitral valve is open (diastole).
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dissipates faster. If cardiac output is low, the cold saline mixes with a smaller volume of blood and the temperature change is more apparent and slower to dissipate.
decision to place a PAC. There is an actual cost and potential complications associated with placement of these catheters.21–28
CONTRAINDICATIONS INDICATIONS The major advantage of the PAC is that it provides accurate measurements of hemodynamic parameters such as pulmonary capillary wedge pressure and cardiac output. This is particularly useful in critically ill patients, as the clinical estimation of these parameters is frequently incorrect.9–13 The PAC may be used for diagnostic or therapeutic purposes. Diagnostically, the PAC is usually used in situations where clinical judgment alone cannot reliably determine the physiologic basis for hemodynamic instability, pulmonary edema, or reduced urine output. Therapeutically, the PAC may help to direct therapy in patients in whom noninvasive clinical parameters are insufficient guides of treatment efficacy. The most common clinical indications for the PAC in medical and surgical patients are listed in Table 53-1. It should be noted that despite the prevalence of PAC use, few prospective studies have documented improved clinical outcomes with the PAC except in perioperative surgical patients. Retrospective studies have suggested that the use of the PAC may be associated with worse outcomes.14–17 Over the last 10 years, this question has been further studied in randomized controlled trials as a result of the retrospective data suggesting worse outcomes with the use of PAC. In all of these trials, PACs do not appear to improve survival or decrease length of stay. However, these trials also do not confirm the suggestion of worse outcomes with the use of PAC. As with any intervention, the Emergency Physician must carefully assess the potential benefits and risks in making the
There are no circumstances in which PAC insertion is absolutely contraindicated. Insertion of a PAC may be relatively contraindicated in cases where the risks of obtaining vascular access (e.g., severe bleeding diathesis) or of passing the catheter (e.g., a mobile thrombus in the right heart or right-sided endocarditis) outweigh the potential benefits of obtaining the data the PAC provides. A PAC is not indicated in situations where it will provide no diagnostic information that cannot be acquired by less invasive means. For example, while a PAC may be helpful in diagnosing or treating patients with mitral regurgitation or ventricular septal defects following myocardial infarction, echocardiography may be sufficiently diagnostic and may obviate the need for a PAC. The same can be true in cases of cardiac tamponade. The PAC may also be superfluous in situations where it will provide little or no therapeutic guidance. The insertion of a PAC is not necessary if a therapeutic trial of fluid administration restores urine output and blood pressure in a hypovolemic patient who has normal cardiac function. Other contraindications include patients with: cardiac dysrhythmias, implanted pacemakers or defibrillators, pulmonary hypertension, right-sided endocarditis, right-sided intracardiac valvular abnormalities, right-sided prosthetic heart valves, rightsided intracardiac thrombi, or severe hypotension. A PAC should not be inserted if the appropriate equipment is unavailable or if personnel experienced with the insertion and interpretation of the PAC data are not present.19,20
EQUIPMENT TABLE 53-1 Common Clinical Indications for Pulmonary Artery Catheter Placement in Medical and Surgical Patients Cardiac A. Complicated myocardial infarction i. Management of refractory hypotension or left ventricular failure ii. In the presence of hemodynamic deterioration due to a mechanical complication, to differentiate mitral regurgitation from acute ventricular septal defect B. Other cardiac conditions i. Diagnose/manage cardiac tamponade ii. Distinguish cardiogenic from noncardiogenic pulmonary edema iii. Management of severe cardiomyopathy iv. Diagnose/manage severe pulmonary hypertension Medical/Surgical In the setting of sepsis, trauma, burns, multiple organ failure, pulmonary embolus, or drug overdose. If any of the following is found to be unresponsive to conventional medical management: A. Hypotension B. Low urine output C. Hypoperfusion (evidenced by cool skin, mental obtundation, and lactic acidosis) D. Severe hypoxemia requiring high levels of PEEP (>10 cm) Preoperative A. High-risk cardiac surgery (e.g., CABG in elderly patients, multiple valve replacement, and ventricular aneurysm resection) B. Complicated vascular surgery (dissecting aneurysm, resection of thoracic or abdominal aneurysm) C. Other surgical patients with multiple risk factors i. Myocardial infarction within 6 months ii. Poor left ventricular function iii. Elevated Goldman or ASA score
• • • • • • • • • • • • • •
Povidone iodine or chlorhexidine solution Sterile gloves and gown Face mask and cap Saline or dextrose solution with or without heparin (1 to 2 U/mL) Pressure bag with manometer Pressure tubing Pressure transducer for distal port (CVP port optional) Stopcocks and occlusive caps for each port of PAC Fluid infusion tubing for sheath sideport and for PAC ports PAC Balloon inflation syringe Catheter sleeve Sterile dressing for site Electrocardiogram (ECG) and pressure monitor
The materials required to place a percutaneous introducer sheath are available in commercially prepared prepackaged kits. Refer to Chapter 49 for the details regarding the placement of the introducer sheath. Note that many PACs require an 8.5 French introducer sheath. In addition, it is desirable to use an introducer sheath that allows the sterile protective sleeve over the PAC to be affixed securely to the sheath. The PAC consists of a balloon lumen that ends in a balloon just proximal to the catheter tip, a distal lumen that opens at the end of the PAC, a lumen that opens approximately 30 cm proximal to the tip, and a thermister (Figure 53-3). Many PACs have one or more additional lumens opening proximal to the tip. Some of these lumens are designed to accommodate a cardiac pacing wire. A 3 mL syringe with a safety stop at 1.5 mL is supplied with each PAC.
CHAPTER 53: Pulmonary Artery (Swan-Ganz) Catheterization Thermister lumen port Distal lumen port
Proximal lumen port
Balloon channel (inflation) port Pressure release valve Extension divided junction
Rounded tip
20 cm
Balloon
10 cm Port FIGURE 53-3. The pulmonary artery catheter.
This syringe is used to inject air into the balloon. Distances from the tip of the PAC are indicated by linear markings on the shaft. By the standard designation, each thin line represents 5 cm increments and each thick line 10 cm increments.
PATIENT PREPARATION Routine laboratory studies are advisable prior to PAC insertion in nonemergent circumstances. Hematologic abnormalities (e.g., severe anemia, thrombocytopenia, and coagulation system deficiencies) can increase the risk or adverse consequences of bleeding. Electrolyte derangements (e.g., hyperkalemia, hypokalemia, and hypomagnesemia) that may predispose to arrhythmias should be identified and corrected when possible. Explain to the patient and/or their representative the risks, benefits, and complications of the procedure. Obtain informed consent for the procedure if possible. The use of mild sedation may be advantageous in some patients. Place the patient supine if possible. Continuous ECG monitoring is essential. Pulse oximetry should be routinely monitored. Arterial pressure monitoring is often desirable in patients receiving a PAC. Apply supplemental oxygen. Equipment and personnel necessary for assisting with the PAC insertion procedure and for managing potential complications should be immediately available. This should include equipment for emergency airway management and emergency cardiac pacing. The choice of which central venous access site to use for PAC insertion must be individualized. The preferred sites are the right internal jugular vein or the left subclavian vein. The PAC tends to
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float into the desired position more easily from these two sites. The left internal jugular vein and the right subclavian vein are acceptable alternatives. The femoral vein may also be used. The femoral approach may be quite difficult without fluoroscopic guidance of the catheter. The external jugular veins, basilic veins, and axillary veins are additional alternatives that carry the same difficulty. It is essential that strict sterile technique be maintained throughout the insertion procedure. The Emergency Physician and their assistant should be wearing sterile gloves, a sterile gown, a face mask, and a cap. A large sterile field is necessary, as is close attention to the long PAC, which can easily become contaminated. It is also very important to take all necessary precautions with syringe needles, scalpel blades, and suture needles to prevent a needlestick injury. Insert a percutaneous introducer sheath into the central venous system. Refer to Chapter 49 for the complete details regarding the insertion of the sheath. If the patient already has a single-lumen or multi-lumen central venous catheter inserted, it may be exchanged for an introducer sheath. Remove any bandages and dressings on the catheter and skin access site. Thoroughly prep the catheter, skin access site, and surrounding skin with povidone iodine or chlorhexidine solution and allow it to dry. Drape a sterile field. Discontinue any infusions through the catheter. Open an introducer sheath kit. Cut any sutures securing the catheter to the skin. Insert a guidewire through the hub of the distal port and into the central venous circulation. Withdraw the catheter over the guidewire. Insert and secure the percutaneous sheath over the guidewire as described in Chapter 49.
TECHNIQUE Set up a bedside sterile table and open the PAC kit. Remove the protective sleeve. It allows later repositioning of the PAC while maintaining sterility. Place the sleeve over the catheter and slide it far back (>60 cm) from the catheter tip. Attach the balloon inflation syringe to the PAC. Inflate the balloon once to confirm the integrity of the balloon. It is a good idea to inflate the balloon in a full bowl of sterile saline and observe for air bubbles to ensure that there are no leaks or gross eccentricities. Allow the balloon to deflate passively. Deflation by aspirating air from the balloon should be avoided as it places undue stress on the balloon. Flush the PAC ports with sterile saline and attach a stopcock to each port. Attach the pressure tubing to the distal port. Flush the entire apparatus, including the PAC and the pressure monitoring system, with sterile saline to ensure that no air remains in any part of the system. Have an assistant set up, calibrate, and level the transducer. Hand the proximal end of the PAC to an assistant to attach to the ECG monitor. Finally, shake the tip of the PAC while observing the pressure waveform on the monitor to confirm that the monitoring system is operative. Insert the PAC through the diaphragm on the introducer sheath, taking care to orient the natural curve of the catheter toward the right ventricular outflow tract. Continue to advance the PAC until it is inserted 10 to 15 cm and exits the sheath. This ensures that the balloon is not inflated within the sheath. Stop advancing the PAC. Inflate air into the balloon and lock the pressure release valve. The PAC should never be advanced through the central venous system with the balloon deflated, as this may provoke ectopy or injure the heart or other vascular structures. Conversely, the PAC should always be withdrawn with the balloon deflated. Pay close attention to the distance markings on the PAC and to the pressure waveform on the monitor when advancing the PAC. Typical pressure waveforms are illustrated in Figure 53-4. The average distances from the different catheter insertion sites
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B. Right ventricle
Pressure
A. Right atrium
(mmHg) 0 20 D. Pulmonary capillary wedge pressure
Pressure
C. Pulmonary artery
(mmHg) 0 FIGURE 53-4. Typical pressure waveforms recorded by the pulmonary artery catheter during insertion.
into each chamber of the heart are listed in Table 53-2. Advance the PAC into the right atrium (Figure 53-4A). Continue to advance the PAC into the right ventricle, which will be apparent by an abrupt change in the pressure waveform (Figure 53-4B). Continue to advance the PAC into the pulmonary artery outflow tract, again confirmed by a change in the pressure waveform (Figure 53-4C). Passing the PAC through the right ventricle may produce some ventricular ectopy, which is generally uncomplicated. Advance the PAC a few centimeters further to produce a wedge tracing (Figure 53-4D). Deflate the balloon. This will result in the reappearance of the pulmonary artery waveform. If the wedge tracing persists, withdraw the PAC with the balloon deflated until the pulmonary artery waveform reappears. Whenever it is unclear where the tip of the PAC is located, deflate the balloon and withdraw the PAC to a spot where the waveform is recognizable. Take notice of the distance marking. Inflate the balloon and advance the PAC until the desired tracing is obtained. Difficulties in passing the PAC into the pulmonary artery may occur in patients with pulmonary hypertension, significant tricuspid regurgitation, or markedly dilated right heart chambers. Instruct the patient to inspire slowly and deeply to increase venous return to the right heart. This may allow the PAC to be advanced successfully. Tilting the patient’s head upward and repositioning the patient on their left side may also be helpful. Fluoroscopic guidance may be necessary if repeated attempts are unsuccessful. Pull up the protective sleeve over the catheter and secure it to the introducer sheath. It is important not to advance the PAC itself during this manipulation. Begin any infusions through the PAC. Secure the PAC, dress the access site, and document correct positioning by obtaining an anteroposterior chest radiograph. The assessment and aftercare of the skin puncture site is described in Chapter 49.
DATA INTERPRETATION As mentioned in the introduction to this chapter, a detailed discussion of PAC data interpretation cannot be undertaken here. However, anyone who places or uses PACs in the management of
critically ill patients should be familiar with the standard information provided by the PAC. The data generated by the PAC can be divided into two categories. The first set of information comprises data that are directly measured and include the right-sided heart pressures, thermodilution cardiac output, and blood gas obtained from a mixed venous sample from the distal pulmonary artery port. These data, including normal values, are listed in Table 53-3. The second set of data comprises the variables that are mathematically derived from the measured data (Tables 53-4 & 53-5). These provide information crucial to understanding cardiac and pulmonary physiology and pathology. Today, this information is routinely available on an instantaneous basis as part of computer software packages that accompany the monitoring equipment. PAC users should become familiar with both sets of information and their application in different clinical situations. The reader is advised to consult a current textbook of cardiology or critical care medicine for a more detailed description of the hemodynamic data provided by the PAC.
COMPLICATIONS In addition to the complications associated with obtaining central venous access and with prolonged use of indwelling catheters (Chapter 49), complications may occur during or after the insertion of the PAC. The complications directly related to the PAC may be divided into those that are associated with catheter insertion and those associated with long-term maintenance (Table 53-6). Both sets of complications can be further divided into those problems where there has been systematic study and the incidence of complications has been published and those that have been observed and published as case reports but the actual incidence of which is unknown. Problems with tracing quality may occur due to problems involving the catheter itself or other parts of the system. Catheter problems include positioning too distal or not distal enough, balloon rupture, or clot formation at the tip. Problems elsewhere in the system include air in the lines, loose connections, failure of the transducer, failure of the wires, or failure of the monitor. The system should be
CHAPTER 53: Pulmonary Artery (Swan-Ganz) Catheterization TABLE 53-2 Average Distances from the Catheter Insertion Site to the Catheter Tip Position* Catheter insertion site Right atrium distance (cm) Right ventricle distance (cm) Subclavian vein 10 20 Right internal jugular vein 15 25 Left internal jugular vein 20 30 Right antecubital vein 45 60 Left antecubital vein 50 65
Pulmonary artery distance (cm) 30–40 35–45 40–50 70–80 75–85
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Wedge distance (cm) 40–45 45–50 50–55 80–85 85–90
* These distances are considered the common estimates for uncomplicated PAC placement in patients with normal-sized hearts. The distances will vary in patients and may be greater, especially in the patient with a dilated right ventricle. Any time there is a gross discrepancy between these distances and the actual observed placement distance, the physician should consider catheter misplacement, catheter looping, or catheter knotting. An immediate portable anteroposterior chest radiograph should be obtained to evaluate the situation.
TABLE 53-3 Variables Obtained from the Pulmonary Artery Catheter Through Direct Measurement Variable Normal values Main utility Cardiac output (CO) 4–6 L/min Diagnosis of shock (high output vs. low output); titration of vasoactive medications Pulmonary capillary wedge 5–15 mmHg Volume status, diuresis, pressure (PCWP) fluid challenges Right atrial pressure (RAP) 0–10 mmHg Status of right ventricle Pulmonary artery pressure (PAP) 15–25 mmHg systolic; Status of right ventricle and 8–15 mmHg diastolic pulmonary circuit 70%–80% Evaluation of oxygen delivery; Mixed venous oxygen pulmonary shunt fraction saturation (SvO2)
Comments Measurement is prone to error; should be indexed to patient’s size Often overinterpreted; must be used with other values Less useful than PCWP Pulmonary artery diastolic can be substituted for PCWP in most patients Best obtained by blood gas from distal pulmonary artery
TABLE 53-4 Derived Variables Obtained from the Pulmonary Artery Catheter Variable Normal values Main utility Systemic vascular resistance (SVR) Pulmonary vascular resistance (PVR) Left ventricular stroke work index (LVSWI) Right ventricular stroke work index (RVSWI) •
Oxygen DO delivery DO2
56 ± 6 g m/m2
Unclear whether value should be indexed to patient’s size Unclear whether value should be indexed to patient’s size Clinical utility uncertain
8.8 ± 0.9 g m/m2
Right ventricular performance
Clinical utility uncertain
900–1100 mL/min
Often amenable to therapy, but controversial Affected by many variables; use is controversial Underused in the evaluation of pulmonary disease
20–200 dynes/s/cm−5
Oxygen consumption VO2
200–250 mL/min
Shock states, anemia, low cardiac output Sepsis, burns, trauma, ventilator patients
Pulmonary shunt fraction (Qs /Qt)
3%–5%
Acute and chronic lung disease
•
Comments
Shock states, vasodilator versus vasopressor therapy (afterload) Pulmonary hypertension; acute and chronic lung disease Left ventricular performance
800–1600 dynes/s/cm
−5
TABLE 53-5 Formulas for the Derivation of Variables SVR = (mean arterial pressure – mean arterial pressure) × 80 cardiac output PVR = (mean pulmonary artery pressure − pulmonary capillary wedge pressure) × 80 cardiac output LVSWI = SV × (mean arterial pressure – pulmonary capillary wedge pressure) 0.0136 body surface area RVSWI = SV × (mean arterial pressure − right atrial pressure) × 0.0136 body surface area (DO2) = [(cardiac output × hemoglobin) × (13.4) × (% O2 saturation)] + (PO2 × 0.0031) (VO2) = (cardiac output × hemoglobin) × (13.4) × (SaO2 − SvO2) Qs /Qt = (pulmonary capillary O2 content − CaO2)/(pulmonary capillary O2 content − CvO2) Key : CaO2, arterial oxygen content; CvO2, mixed venous oxygen content; PO2, partial pressure of oxygen; SaO2, arterial oxygen saturation; SV, stroke volume. Other terms are defined in Tables 53-3 and 53-4.
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TABLE 53-6 Recognized Complications of Pulmonary Artery Catheterization Related to catheter insertion (published incidence) Complete heart block (0%–2.6%) Ventricular arrhythmias requiring treatment (0%–3%) Hematoma (0%–3%) Air embolism (0.1%) Pneumothorax (0.1%–1.5%) Inability to place catheter with multiple attempts (1.7%) Injury to great vessels (0.1%–13%) Ventricular arrhythmias (20%–50%) Related to catheter insertion (reported, but incidence unpublished) Hemothorax Hemomediastinum Lymphatic duct perforation Injury to trachea Injury to phrenic or vagus nerve Guidewire embolism Catheter knotting (requiring surgical removal) Cardiac perforation Related to long-term maintenance (published incidence) Pulmonary artery rupture (0%–0.5%) Pulmonary infarction (0%–0.5%) Catheter infection (1%–5%) Related to long-term maintenance (reported, but incidence unpublished) Catheter shearing with embolization Misreading or misunderstanding of data provided by catheter
zeroed and calibrated again to confirm the accuracy of the pressure values if abnormally high or low values are obtained. Sometimes it is just not possible to obtain a good wedge tracing despite repeated attempts. In such cases, the pulmonary diastolic pressure may be used as a surrogate for the wedge. A right bundle branch block may occur due to impact of the PAC with the right side of the septum during insertion. This is usually transient. Even if it persists for hours, it is well tolerated in most patients. However, superimposition of a right bundle branch block in the presence of a preexisting left bundle branch block leaves the patient with complete heart block. This complication can result in severe bradycardia and hemodynamic embarrassment. It is important to be prepared to institute temporary transcutaneous or transvenous pacing when placing a PAC in patients with a left bundle branch block. Arrhythmias during insertion, most commonly premature ventricular beats, are usually due to irritation of the right ventricle. This is especially true of the outflow tract. Premature ventricular contractions are usually well tolerated unless sustained ventricular tachycardia or ventricular fibrillation occurs. Slight withdrawal and redirection of the PAC is usually adequate. Arrhythmias after insertion may be due to catheter loops in the right heart, which will be apparent on the chest radiograph and can be corrected by careful withdrawal of the PAC until the loop is removed. Arrhythmias may also occur if the PAC tip slips back into the right ventricle. In this case, the pressure tracing will show a typical right ventricular waveform. Readvancement of the PAC into the pulmonary artery should eliminate the arrhythmias. Other potentially serious but rare complications during placement include injuries to the great vessels, trachea, lymphatic duct, vagus nerve, or phrenic nerve as well as a pneumothorax, hemothorax, hemomediastinum, and cardiac perforation. On occasion, the PAC can become knotted intravascularly or within the heart during placement. This requires an Interventional Radiologist to unknot it or surgical removal if this fails.
The most serious complications related to long-term maintenance of the PAC are pulmonary artery rupture, pulmonary artery infarction, and catheter infection. Pulmonary artery rupture is usually the result of the catheter becoming overwedged and/or the balloon over-inflated. Pulmonary infarction has been seen primarily in patients with mitral regurgitation or pulmonary hypertension and may be avoided if the duration of balloon inflation is kept to a minimum. Catheter infection occurs in 1% to 5% of PAC placements and can be minimized by strict sterile maintenance of the PAC as well as continually reevaluating the need for the PAC and keeping the placement time as short as possible. The majority of PACs should be used for 72 hours or less.
SUMMARY Since its introduction four decades ago, the PAC was initially embraced by Emergency Physicians and Critical Care Physicians for its ability to provide real time information regarding variables such as cardiac output and pulmonary capillary wedge pressure at the bedside. PAC use had become common practice. However, over the last 15 years this has come into significant question. At this point, the utility of the PAC is unclear. The PAC has not led to improved outcomes, decreased mortality, or decreased ICU length of stay. Thus, its use as common practice cannot be supported. However, there are still many clinical situations for which the use of the PAC may benefit the Emergency Physician to make crucial decisions. The PAC is a tool in the armamentarium of any clinician taking care of critically ill patients. Therefore, it is important to be well versed in the information that it provides and its application in the clinical context of the disease state that they are managing.
54
Peripheral Venous Cutdown Flavia Nobay
INTRODUCTION Venous access in the critically ill patient is of the utmost importance. The literature regarding peripheral venous cutdowns extends back to 1940 when Keeley introduced this technique as an alternative to venipuncture in patients with shock.1 Interestingly, there has been a noticeable lack of recent investigations regarding venous cutdowns, most likely due to the focus on central venous access via the Seldinger technique with ultrasound guidance and intraosseous access. Recent editions of the ATLS text refer to the saphenous venous cutdown as an optional skill to be taught at the discretion of the instructor.2 However, despite the apparent lack of popularity of the peripheral venous cutdown, the importance of obtaining venous access in critically ill patients supports the need to know a wide variety of techniques in order to be successful in every situation. The steps outlined in 1940 by Keeley to expose and cannulate the saphenous vein remain mostly unchanged.1 Peripheral venous access can be extremely difficult due to vascular collapse from shock, vascular injury, obesity, or scars. Direct visualization of the vein to be cannulated can be more fruitful than indirect visualization with central venous lines without ultrasound guidance in the patient with shock. However, in a study in 1994 comparing venous cutdowns versus percutaneous femoral venous access, all times to completion of the procedure and infusion times were faster in the percutaneous femoral access group versus the cutdown
CHAPTER 54: Peripheral Venous Cutdown
group.3 Despite these statistics, it is not uncommon to be managing a critically ill patient who cannot be cannulated peripherally or centrally and the venous cutdown becomes a procedure of necessity for resuscitation. An additional advantage of the venous cutdown is that it does not interfere with concurrent resuscitative efforts at the head, neck, thorax, and abdomen. Familiarity with this procedure allows for large-bore access and the rapid infusions required in the critically ill trauma or medical patient with difficult access. All Emergency Physicians should be familiar with the peripheral venous cutdown in order to effectively manage resuscitations in the trauma or medical setting. This technique can only be successfully performed if one understands the anatomy and details of venous cannulation. Practicing the cutdown technique before its critical need will help one to perform optimally in the emergent setting.
ANATOMY AND PATHOPHYSIOLOGY There are three critical areas for venous cutdowns (Figure 54-1). All Emergency Physicians should be knowledgeable of the anatomy of the saphenous vein at the ankle, the saphenous vein at the groin, and the basilic vein at the elbow. The potential injury to the patient can be significant if one approaches this procedure without regard to the clinical anatomy.
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GREATER SAPHENOUS VEIN The greater saphenous vein is the longest vein in the body. It is the ideal vein for a peripheral venous cutdown due to its anatomical regularity and superficiality (Figure 54-2). The superficial and consistent position of the saphenous vein, in both adults and children, makes this the ideal vessel for a peripheral venous cutdown. The saphenous vein begins at the medial dorsal venous arch of the foot. It passes upward and 1.5 to 2.5 cm directly anterior to the medial malleolus (Figure 54-2A). At the level of the medial malleolus, the saphenous vein lies just above the periosteum of the tibia.4 It continues to ascend in the leg, along with the saphenous nerve, in the superficial fascia over the medial aspect of the leg. The vein passes posteromedially to the knee. Above the knee, it curves forward onto the anteromedial thigh. It passes over the falciform margin of the deep investing fascia to join the femoral vein approximately 4 cm below and 3 cm lateral to the pubic tubercle (Figure 54-2B). The greater saphenous vein is easily identified at the ankle. It will be found, approximately, 2.5 cm anterior and 2.5 cm superior to the medial malleolus. It may be palpable if the patient is not hypovolemic or obese. The saphenous nerve, a branch of the femoral nerve, travels with the greater saphenous vein. It supplies sensory innervation to the skin of the medial leg and foot as far as the first metatarsal. This nerve is often transected when isolating the greater saphenous vein at the ankle. Fortunately, this nerve is of minimal clinical significance. The saphenous vein in the thigh travels on the anteromedial surface and enters the fossa ovalis to join the femoral vein (Figure 54-2B). The femoral vein is at its largest diameter 3 to 4 cm distal to the inguinal ligament. This is approximately 2 cm distal to the approach for the placement of a femoral central venous line, at the same level where the scrotal or labial fold meets the thigh. The greater saphenous vein is also at its largest diameter in this location. At the level of the scrotal or labial fold meeting the thigh, the greater saphenous vein is easily isolated from the surrounding subcutaneous tissue. If the deep investing fascia of the thigh muscles is visible, the dissection has progressed deeper than the position of the greater saphenous vein.
BASILIC VEIN
FIGURE 54-1. Common sites for peripheral venous cutdowns include the inner arm above the elbow (1), the inner thigh (2), and the inner ankle (3).
The basilic vein is the site of choice for a peripheral venous cutdown in the upper extremity (Figure 54-3). It can be traced starting from the dorsal venous arch of the hand. It ascends on the posteromedial forearm to become anteromedial on the mid-toupper forearm. It continues to ascend to the midportion of the arm where it pierces the deep fascia. The basilic vein runs in the groove between the biceps and triceps muscles in the distal one-third of the arm. The vein can always be found in the groove between the biceps and triceps muscles. A peripheral venous cutdown should be performed in this location. The basilic vein is more consistently found 2 cm cephalad and 1 to 2 cm lateral to the medial epicondyle of the humerus on the volar (anterior) surface of the arm. The brachial artery and median nerve lie deep to the basilic vein in this location and are unlikely to be injured if the dissection remains superficial. Simon et al. recommend the approach to the basilic vein through the groove between the biceps and triceps muscles in the distal one-third of the arm.5,6 These authors feel that locating the vein above and lateral to the medial epicondyle of the humerus will result in difficult cannulation secondary to the surrounding dense venous plexus. There is a significant risk of injury to the medial antebrachial cutaneous nerve and the deep brachial artery if one tries to find and isolate the basilic vein in the middle third
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FIGURE 54-2. Anatomy of the greater saphenous vein. A. The subcutaneous course of the vein in the lower extremity. B. Detail of the greater saphenous vein at the groin.
or proximal third of the arm. Injury to the median antebrachial cutaneous nerve will result in sensory loss to the ulnar aspect of the forearm.
BRACHIAL VEIN Brachial vein cutdowns should not be performed in the Emergency Department. The brachial vein is small in diameter. It is located relatively deep and would require significant and time-consuming steps to locate it. The anatomical structures surrounding the brachial vein include major arteries and nerves that can easily become injured while isolating the vein. Patients in hypovolemic shock will often not have a brachial artery pulse. This can lead to confusion as to which vessel is the artery and which is the vein.4 Inadvertent cannulation of the brachial artery can result in a brachial artery thrombosis and upper extremity ischemia.
AXILLARY VEIN The axillary vein is rarely used as a site for a venous cutdown. The axillary vein, in the axilla, is contained within the axillary sheath. Also contained within the axillary sheath are the axillary artery and brachial plexus. A venous cutdown for the axillary vein can injure these structures and is associated with a high rate of complications. It is not recommended to perform a cutdown for the axillary vein unless the Emergency Physician has specific experience with this particular technique.
INDICATIONS The primary indication for a peripheral venous cutdown is the need for venous access in a patient with no peripheral access and in whom central access is not obtainable or contraindicated. This is the ideal procedure for the intravenous drug user with no peripheral veins and scarred central access sites, the burn patient with peripheral venous collapse and scarring, the patient in cardiorespiratory arrest, or the hypovolemic trauma patient that requires definitive and lifesaving volume resuscitation.7 Hypovolemic shock is well treated with peripheral venous cutdowns because a unit of blood can be infused in less than 3 minutes with intravenous extension tubing inserted directly into the vein.4 This is also an excellent technique for emergent pediatric vascular access. Direct visualization of the vein will aid in cannulation of a vessel that may be collapsed secondary to hemorrhage, hypovolemia, and/or shock. This technique should only be used after other access attempts (i.e., interosseous access, ultrasound-guided central venous access, peripheral venous access—including scalp veins) have failed.8
CONTRAINDICATIONS The absolute contraindications to a peripheral venous cutdown are vascular injury, saphenous vein removal, or long bone fractures proximal to the cutdown site. Relative contraindications include infection overlying the cutdown site, bleeding disorders, or severely
CHAPTER 54: Peripheral Venous Cutdown
Cephalic vein
Basilic vein Median cephalic vein
Cephalic vein
Median basilic vein
Basilic vein
Median vein of forearm
FIGURE 54-3. The superficial veins of the upper extremity.
distorted anatomy from congenital malformations, blunt trauma, or penetrating trauma in the area of the cutdown or the limb. A cutdown should not be performed unless peripheral intravenous access has failed and intraosseous access equipment is not available or has failed.
EQUIPMENT • • • • • • • • • • • • • • •
Povidone iodine or chlorhexidine solution Local anesthetic solution 10 mL syringe 22 gauge needle #10 scalpel blade #11 scalpel blade #3 scalpel handle Curved Kelley hemostat Small mosquito hemostat Vein pick Fine tooth forceps Iris scissors Sharp tissue-cutting scissors Sterile drapes Towel clips
• • • • • • • • • • • • • • •
353
Sterile polyethylene intravenous tubing Sterile intravenous extension tubing Central line kit (for Seldinger method) Catheter-over-the-needle, 16 or 18 gauge Sterile 4 × 4 sponges 5 mL syringe 18 gauge needles Self-retaining skin retractors Small rake, two Needle driver Silk suture, 3-0 and 4-0 Injectable sterile saline Intravenous tubing and solution Wound dressing supplies Antibiotic ointment
PATIENT PREPARATION The patient is usually in extremis and positioned supine if a peripheral venous cutdown is to be performed. They may also be in the Trendelenburg position, although this is not ideal for the procedure. The limb selected for the peripheral venous cutdown should be secured to the bed with a restraint, tape, or by an assistant. Although this is an emergent procedure, time should be taken to perform it in as sterile a manner as possible. Identify the landmarks for the procedure. Clean the skin of any dirt and debris. If the patient is awake and aware of the surroundings, the area of the cutdown should be anesthetized. Infiltrate local anesthetic solution into the subcutaneous tissue where the incision will be made. Prepare the skin with povidone iodine or chlorhexidine solution and allow it to dry. Apply sterile drapes to isolate a surgical field. Collect and set up all the required equipment on a bedside table covered with a sterile drape.
TECHNIQUES TO ISOLATE THE VEINS The technique of cannulation is the same regardless of the vein chosen. The methods to isolate the saphenous vein and the basilic vein will be discussed in this section. A discussion of three different techniques to cannulate the isolated vein will be presented in the following section.
GREATER SAPHENOUS VEIN ISOLATION AT THE ANKLE The saphenous vein is easily found and isolated at the ankle (Figure 54-4). Extend and externally rotate the lower extremity. Identify the medial malleolus of the tibia. Find the location 2.5 cm anterior and 2.5 cm superior to the medial malleolus. The greater saphenous vein will be found at this site. Alternatively, place your index and middle fingers at the level of the malleolus (Figure 54-4A). The vein will be found two finger breadths cephalad and two finger breadths in anterior of the medial malleolus. The vein may be palpable if the patient is not hypovolemic or obese. Alternatively, the vein may be visualized in patients with thin skin, superficial veins, minimal subcutaneous tissue, or dark vessels. Stretch the skin taught over the distal tibia with the nondominant hand (Figure 54-4B). Note the position of the hands in the illustration. The nondominant hand is placed with the fingertips pointing toward the Emergency Physician. This will prevent inadvertent injury while making the skin incision. Transversely
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FIGURE 54-4. Isolation of the greater saphenous vein at the ankle. A. Identifying the vein. B. A transverse skin incision is made from the anterior to the posterior border of the medial tibia. C. The tip of a curved hemostat is scraped along the tibia then rotated 180° (curved arrow). D. The hemostat is spread to separate the tissues. E. A straight hemostat is inserted between the jaws of the curved hemostat to elevate the vein. F. The curved hemostat has been removed.
CHAPTER 54: Peripheral Venous Cutdown
incise the skin overlying the great saphenous vein using a #10 scalpel blade, from the anterior tibial border to the posterior tibial border after appropriate anesthesia (Figure 54-4B). This incision should be superficial so that the subcutaneous tissue is barely exposed. A deep incision may transect the vein causing significant bleeding, difficulty visualizing the surgical field, and difficulty finding the ends of the vein that retract proximally and distally. Apply tension to the skin on either side of the incision to expose the underlying structures. This can be accomplished with the nondominant hand, a self-retaining retractor, or skin rakes held by an assistant. Isolate the greater saphenous vein.5 This may be difficult in some patients in shock or patients in the Trendelenburg position as the vein may be poorly perfused. Grasp and hold a curved hemostat (Kelly clamp) with the tip facing downward. Insert the hemostat along the posterior border of the tibia and scrape the tip anteriorly along the tibia (Figure 54-4C). If done properly, all of the tissue between the skin and the tibia will be above the hemostat. Rotate the hemostat 180° (Figure 54-4C). The tip of the hemostat will be facing upward (Figure 54-4D). Widely open the arms of the hemostat (Figure 54-4D). This will open the jaws of the hemostat and separate the saphenous vein from the saphenous nerve and fibrous strands of connective tissue. The saphenous vein should be visible between the jaws of the hemostat. If there is difficulty identifying the vein, squeeze the foot to backfill the vein with blood. Insert a straight hemostat (Kelly clamp) between the jaws of the curved hemostat and below the greater saphenous vein (Figure 54-4E). Remove the curved hemostat to leave the straight hemostat elevating the greater saphenous vein (Figure 54-4F). This straight hemostat will be useful as a “cutting board” to later transect the vein by allowing more manual control of the vein. An alternative technique to isolate the vein is used by some Physicians. This technique is not recommended by the editor but is briefly described for the sake of completeness. Make the transverse skin incision. Place the jaws of a curved hemostat parallel to the greater saphenous vein. Open the arms of the hemostat to allow the jaws to dissect through the subcutaneous tissue. Continue placing the hemostat and opening the jaws until the vein is isolated. This technique is harder to perform because the vein is less likely to be identified given the white background of the periosteum.1,8,9 Additionally, this technique takes significantly longer to find and isolate the vein.
GREATER SAPHENOUS VEIN ISOLATION AT THE GROIN The groin vasculature offers the potential for massive infusion of blood or fluids in a matter of minutes. These vessels are closer to the central circulation and large enough to easily accommodate intravenous tubing, cut off at a 45° angle, as a catheter. The greater saphenous vein is superficial at the groin and lies in a meshwork of subcutaneous tissue. It is superficial to the femoral artery and vein. The saphenous vein travels on the anteromedial surface of the thigh and enters the fossa ovalis to join the femoral vein (Figure 54-2B). The greater saphenous vein is at its largest diameter 3 to 4 cm distal to the inguinal ligament. This is approximately 2 cm below the site for placement of a femoral central venous line and level with where the scrotal or labial fold meets the thigh. Identify the location where the scrotal or labial fold meets the thigh (Figure 54-5). Identify the lateral edge of the mons pubis. Identify the point where a vertical line from the lateral edge of the mons pubis meets a horizontal line from the scrotal/labial fold. Make a transverse, medial to lateral, incision with a #10 scalpel blade on the patient’s thigh starting where the scrotal or labial fold meets the
Femoral artery
Femoral vein
355
Great saphenous vein
6 cm
Incision line
FIGURE 54-5. Isolation of the greater saphenous vein at the groin. The skin incision should begin where the scrotal or labial fold meets the thigh. Extend the incision laterally until it meets a vertical line from the lateral edge of the mons pubis.
thigh after appropriate anesthesia. Extend the incision laterally until it meets the vertical line from the lateral edge of the mons pubis. Dissect the subcutaneous tissue to locate the greater saphenous vein. Place the jaws of a curved hemostat parallel to the greater saphenous vein. Open the arms of the hemostat to allow the jaws to dissect through the subcutaneous tissue. Continue placing the hemostat and opening the jaws until the vein is isolated. The dissection is too deep if the deep investing fascia or the muscle bellies of the thigh muscles are encountered. Stop, reidentify the landmarks, and adjust the skin incision and dissection as necessary. Alternatively, the subcutaneous tissues can be bluntly dissected using 4 × 4 gauze squares. Grasp two or three gauze squares in each hand. Put the fingertips of both hands, covered with gauze, in the center of the incision. Move the hands in opposite directions, cephalad and caudad, while scraping the subcutaneous tissue with the gauze. Reapply the hands in the incision and repeat the motion until the greater saphenous vein is exposed. This technique applies pressure parallel to the greater saphenous vein and will not injure the vein.
BASILIC VEIN ISOLATION AT THE ELBOW The basilic vein may be used for a peripheral venous cutdown. This is often performed when the greater saphenous vein cannot be accessed due to lower extremity amputation, deformity, injury, or trauma. This site is not ideal as it may interfere with resuscitative efforts while the basilic vein is being exposed. The basilic vein is consistently found 2 cm cephalad and 1 to 2 cm lateral to the medial epicondyle of the humerus on the volar surface of the arm. It may also be found in the groove between the biceps and triceps muscles. There is controversy in the literature as to where the incision for the basilic vein cutdown should be performed. The simple answer is that if one fails in isolating the vein in one location, make an incision in the second location to isolate the vein. Position the patient to allow exposure of the basilic vein. Abduct the patient’s arm 90° with the elbow flexed 90° and the palm facing upward (Figure 54-6). This positioning is required to access the basilic vein at either location.
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Basilic vein Incision line Brachial artery
3 cm Medial epicondyle of humerus FIGURE 54-6. Isolation of the basilic vein.
Identify the point 2 cm cephalad and 2 cm lateral from the medial epicondyle of the humerus. This is the location of the basilic vein. Make a 4 to 6 cm transverse incision with a #10 scalpel blade centered on the reference point after appropriate anesthesia. The incision should only cut through the epidermis. Bluntly dissect the subcutaneous tissue with a curved hemostat or 4 × 4 gauze squares, as described previously, to locate the basilic vein. The dissection is too deep if the brachial artery, median nerve, or muscle fibers are encountered. Stop, reidentify the landmarks, and adjust the skin incision as necessary. Alternatively, the basilic vein can be isolated in the middle of the distal third of the arm. Palpate the groove between the biceps and triceps muscles. This is the location of the basilic vein. Make a 4 to 6 cm horizontal incision centered about the groove after appropriate anesthesia. Bluntly dissect with a curved hemostat until the vein is located. The basilic vein is superficial to the muscle fascia and the brachial artery.
TECHNIQUES FOR CANNULATION OF THE VEIN There are a number of techniques to cannulate a vein after it has been isolated. Either of the following techniques can be used to cannulate the greater saphenous vein or the basilic vein. It is important to realize that this may be a lifesaving procedure in an emergent setting, and the rapid and definitive cannulation of the vessel is the primary goal and not the technique chosen.
SURGICAL TECHNIQUE USING INTRAVENOUS TUBING Isolate the chosen vein as described previously. Place a straight hemostat (Kelly clamp) under the midportion of the vein
(Figure 54-7A). Slightly elevate the hemostat. Pass a silk suture under the vein at its proximal end and a second silk suture at its distal end (Figure 54-7B). Grasp the silk sutures with a hemostat to maintain the position of the tie and to allow for manipulation of the vein. Tie the distal suture to occlude inflow of blood from distal veins (Figure 54-7C). Do not cut either of these two sutures. The proximal suture will be left untied at this time to allow for control and manipulation of the vein. Have an assistant prepare the catheter. Attach sterile intravenous polyethylene tubing to a bag of sterile saline. Cut the angiocatheter attachment hub off the end of the tubing at a 45° angle. Some authors suggest using a feeding tube instead of intravenous tubing.8 This is not recommended. Intravenous tubing is ubiquitously available. With a feeding tube, the rounded tip may be more difficult to advance into the vein. The only advantage to using a feeding tube is that the rounded tip has less chance of puncturing the posterior wall of the vein. Incise the vein. With the nondominant hand, grasp the hemostat holding the proximal suture. Raise the hemostat to flatten the vein and prevent back bleeding. Make an incision through half of the vein with the tip of a #11 scalpel blade (Figure 54-7D). Do not cut the entire vein as this will cause significant bleeding and loss of the proximal end. If the incision is too large, greater than onehalf the vein’s diameter, the vessel may be torn completely and retract from the surgical field.8 The straight hemostat below the vein will act as a “cutting board” and prevent injury to underlying structures from the scalpel blade. As an alternative, the jaws of the straight hemostat can be opened and the vein cut with an iris scissors (Figure 54-7E). Insert the intravenous tubing into the vein. Gently relax the tension on the proximal suture to allow the vein to open. Advance the intravenous tubing 2 to 3 cm into the vein (Figure 54-7F). Often times, there is considerable difficulty advancing the catheter. Do not force the catheter through the vein as it is very delicate. Troubleshoot by removing the catheter and make sure that the lumen of the vein has been cannulated. This is sometimes difficult to accomplish. If so, have an assistant control the proximal suture. Using a mosquito hemostat, grasp the cut edge of the vein and lift upward to expose the vein’s lumen and insert the intravenous tubing (Figure 54-7G). For small veins, a mosquito hemostat may be too large to grasp the cut edge of the vein. Insert a vein pick or an 18 gauge needle with the tip bent into a 90° angle into the lumen of the vein (Figure 54-7H). Lift upward to expose the vein’s lumen and insert the intravenous tubing. After inserting the intravenous tubing, palpate the posterior aspect of the vein for penetration of the catheter. The catheter must be removed if it penetrates through the posterior wall of the vein. Release the proximal suture and allow the intravenous fluid to flow into the vein if the tubing has not penetrated the posterior wall of the vein. Tie the proximal suture to secure the intravenous tubing within the vein if the fluid flow is unobstructed and the fluid is not extravasating into the surrounding tissues (Figure 54-7I). Do not tie the suture too tight to occlude the tubing. Tying the suture too tightly may also result in a thrombosis.10 If the tubing is within the lumen of the vein and the fluid is not flowing, the tubing may be against a venous valve. Gently advance the catheter 2 to 3 mm or withdraw it 2 to 3 mm and observe the fluid for flow. It is not necessary to close the skin incision at this time. Place saline moistened gauze over the incision site. Wrap a sterile dressing (e.g., Kerlix) around the extremity and the skin incision site. If the patient survives the episode for which a venous cutdown was performed, the skin incision must be closed. If the intravenous tubing was inserted as above, the skin incision will be sutured
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FIGURE 54-7. Venous cannulation using intravenous tubing. A. The vein has been isolated. B. A silk suture has been placed proximally and distally around the vein. C. The distal suture is tied. D. An incision is made through half of the vein with a #11 scalpel blade. E. Alternatively, the hemostat is opened and an iris scissors is used to cut half of the vein. F. The catheter is inserted into the vein and advanced. G. A mosquito hemostat can be used to grasp the vein and hold it open while the tubing is inserted. H. For small veins, a vein pick or 18 gauge needle with the tip bent can be used to hold open the vein. I. The proximal suture is tied to secure the tubing.
closed and the tubing will exit the incision. This is not optimal, according to some physicians, as it may allow access of bacteria through the wound and into the underlying vein. An alternative method is available (Figure 54-8). After exposing the vein, grasp and elevate the distal skin edge with a hemostat. Make a stab incision with a #11 scalpel blade approximately 1 cm distal to the
previously made skin incision (Figure 54-8A). Use caution not to cut the underlying vein. Insert the intravenous tubing through the stab incision and pull it through the skin incision. Incise the vein and insert the tubing as described previously. This allows the tubing to be tunneled through the subcutaneous tissue before cannulating the vein (Figure 54-8B).
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FIGURE 54-8. Alternative technique of venous cannulation with intravenous tubing. A. The distal skin edge is elevated. A #11 scalpel blade is used to make a stab incision in the skin and subcutaneous tissues. B. The tubing is fed through the stab incision and into the vein.
SELDINGER TECHNIQUE Another technique of venous cannulation uses the Seldinger method.9,11 This technique will insert the catheter as if cannulating a central vein. Refer to Chapter 49 for complete details. All of the required equipment can be found in a prepackaged central venous line access kit. This includes the guidewire, introducer sheath, dilator, and the venous catheter. This technique can accommodate a large caliber line, such as an 8 or 9 French introducer sheath. This technique may save 1 to 2 minutes on cannulation time by eliminating the ligature and tie off steps. Isolate the chosen vein as described previously. Place a straight hemostat (Kelly clamp) under the midportion of the vein and open the jaws (Figure 54-9A). Insert the catheter-over-the-needle into the vein (Figure 54-9A). Stop advancing the catheter-overthe-needle when a flash of blood is seen in the needle hub. Be cautious not to puncture the posterior wall. Remove the straight clamp. Advance the catheter into the vein while securely holding the needle. Remove the needle. Insert the guidewire through the catheter. Remove the catheter by backing it out over the guidewire which will remain in the vein. Place the dilator through the introducer sheath. Feed the dilator–introducer sheath unit over the guidewire (Figure 54-9B). Advance the unit into the vein with a twisting motion while securely holding the guidewire (Figure 54-9C). Continue to advance the unit until the hub of the introducer sheath is just above the vein (Figure 54-9D). Remove the guidewire and dilator as a unit (Figure 54-9D). Attach intravenous tubing to the hub of the introducer sheath and begin instilling fluids. It is not necessary to close the skin incision at this time. Place saline-moistened gauze over the incision site. Wrap a sterile dressing (e.g., Kerlix) around the extremity and the skin incision site.
MODIFIED SELDINGER TECHNIQUE An alternative and quicker method can be used to insert the introducer sheath into the vein (Figure 54-10). Isolate the chosen vein as described previously. Place a straight hemostat (Kelly clamp) under the midportion of the vein and open the
FIGURE 54-9. The Seldinger technique of venous cannulation. A. The vein has been isolated. The catheter-over-the-needle is inserted into the vein. B. A guidewire has been placed into the vein. The dilator and sheath are fed over the guidewire. C. The dilator and sheath are advanced into the vein with a twisting motion. D. The guidewire and dilator are removed as a unit.
jaws (Figure 54-10A). Assemble the unit by placing the dilator through the sheath and insert the guidewire through the dilator (Figure 54-10B). The guidewire should protrude 3 to 4 mm beyond the tip of the dilator. Make an incision in the lateral half of the vein (Figure 54-10C). While holding the proximal guidewire and sheath, insert the distal guidewire into the vein. Continue to insert the entire unit with a twisting motion into the vein (Figure 54-10D). Continue to advance the unit until the hub of the introducer sheath is just above the vein. Remove the guidewire
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FIGURE 54-11. Intravenous catheter technique of venous cannulation. A. A catheter-over-the-needle is inserted into the vein. B. A catheter-over-the-needle is inserted through the skin and into the vein. FIGURE 54-10. The modified Seldinger technique of venous cannulation. A. The vein has been isolated. B. The dilator, guidewire, and sheath are assembled as a unit. C. An incision has been made in the vein. D. The unit is inserted into the vein, guidewire first. A twisting motion will aid in its insertion. E. The guidewire and dilator are removed as a unit.
and dilator as a unit (Figure 54-10E). Attach intravenous tubing to the hub of the introducer sheath and begin instilling fluids.
INTRAVENOUS CATHETER TECHNIQUE This final technique involves the insertion of a standard, 16 to 18 gauge, intravenous catheter-over-the-needle into the vein (Figure 54-11). This technique is sometimes referred to as the mini-cutdown. The vein is cannulated under direct visualization through a skin incision. This technique will insert the catheter as if cannulating a peripheral vein. Refer to Chapters 47 and 48 for complete details. This method is very quick, provides a more secure cannulation, and potentially decreases the chance of infection.
Isolate the chosen vein as described previously. Place a straight hemostat (Kelly clamp) under the midportion of the vein and open the jaws (Figure 54-11A). Insert the catheter-over-the-needle into the vein under direct visualization (Figure 54-11A). Stop advancing the unit when a flash of blood is seen in the needle hub. Advance the catheter into the vein while removing the straight clamp. Advance the catheter until the hub is just above the vein. Remove the needle. Attach intravenous tubing to the catheter hub and begin instilling fluids. Gently tie the proximal suture to secure the catheter within the vein. It is not necessary to close the skin incision at this time. Place saline-moistened gauze over the incision site. Wrap a sterile dressing (e.g., Kerlix) around the extremity and the skin incision site. Alternatively, insert the catheter-over-the-needle through the skin, 1 cm distal to the distal skin edge, until the tip is visualized in the incision (Figure 54-11B). Insert the catheter-over-the-needle into the vein under direct visualization. Stop advancing the unit when a flash of blood is seen in the needle hub. Advance the catheter into the vein while removing the straight clamp. Advance
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FIGURE 54-12. The skin incision is closed with interrupted 4-0 nylon sutures. The catheter exits a separate skin incision (A) or the original skin incision (B) and is secured with a suture.
the catheter until the hub is against the skin. Remove the needle. Attach intravenous tubing to the catheter hub and begin instilling fluids. The advantage of this method is that the catheter goes through the skin, which will stabilize the catheter and prevent it from becoming dislodged.
AFTERCARE Suture the wound closed with simple interrupted 4-0 nylon sutures (Figure 54-12). Place a suture through the skin, wrap it around the catheter and tie it to secure the catheter to the skin. Apply antibacterial ointment to the incision, the sutures, and the site where the catheter exits the skin. Secure the intravenous tubing (Figure 54-13). The catheter can be looped around the toe, for a cutdown at the ankle, and secured with gauze wrap or an elastic wrap (Figure 54-13A). The catheter can be secured by taping it to the skin (Figure 54-13B). The limb can be immobilized on a board, after the catheter is secured at the ankle or elbow, for added security from inadvertent dislodgement of the catheter (Figure 54-13C).
FIGURE 54-13. Securing the intravenous catheter. A. The catheter is looped around the great toe, for an ankle cutdown, and secured with gauze or elastic wrap. B. The catheter is secured with tape. C. The ankle or elbow can be secured to a board for additional security.
COMPLICATIONS The complications of a peripheral venous cutdown include arterial injury, nerve injury, phlebitis, thromboembolism, wound dehiscence, and wound infection. The incidence of complications ranges from 2% to 15%.12,16 The difficulty in reporting complications is that there is a high mortality rate in patients undergoing this procedure
due to the primary problem (e.g., hypovolemia, sepsis, shock, trauma, etc.). The knowledge of the local anatomy and the technical aspects of the various cutdown techniques may avoid arterial, venous, and nerve injury. The other complications may be reduced by removal of the catheter within 12 hours after placement.16
CHAPTER 55: Intraosseous Infusion
PHLEBITIS It is generally agreed that phlebitis occurs more commonly in the lower extremity than the upper extremity. However, there are little data to support this. Phlebitis usually results from prolonged catheterization. It may be seen within hours of catheter placement and as long as 18 days after the removal of the catheter.16 In 1960, Bogen looked at 234 ankle cutdowns and found a 4% phlebitis rate.14 He felt this was secondary to infection. The strength of the correlation was attributed to a previous nonrelated study that found Staphylococcus aureus on almost all catheter tips in patients with phlebitis as opposed to catheter tips in patients without phlebitis. Interestingly, these cases of phlebitis all resolved without the use of antibiotics. Moran et al. cultured 89 cutdown sites and observed that the pathogenic species causing infection were S. aureus, Enterococcus, and Proteus. These organisms were cultured more frequently in patients that had cutdowns that were left in place for longer periods of time. Moran et al. did not find a correlation between infection and phlebitis and postulated that phlebitis was due to irritation of the vein wall by the catheter.13 Regardless of the rates and species, it is clear from all of these studies that early removal of the intravenous catheter within 12 hours of placement will significantly decrease the incidence of phlebitis.
INFECTION Moran et al. did not find that prophylactic antibiotics reduced infection rates.13 They found that daily topical antibiotic ointment, in particular Neosporin , reduced positive local wound cultures from a rate of 78% to 18%. In 1968, Collins et al. studied polyethylene catheters and found a 2% bacteremia rate and a 1% death rate from Pseudomonas species in debilitated patients.15 Rhee et al. in 1988 found only one case of cellulitis in their study of 78 patients.11 Regardless of the rates and species, it is clear from all of these studies that early removal of the intravenous catheter within 12 hours of placement will significantly decrease the incidence of infection and subsequent complications. Obviously, sterile technique is also encouraged with this procedure in order to minimize complications related to infection.
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ASSOCIATED INJURIES Injury to adjacent arteries, nerves, and veins can be avoided by a detailed understanding of the local anatomy and careful procedural technique. Aggressive and forceful dissection without an understanding of the anatomy or the procedure will increase the incidence of complications. Injury to adjacent cutaneous nerves is unavoidable and inconsequential. Venous spasm, which causes nonuniform acceptance of the intravenous extension tubing, may also occur.16
SUMMARY The peripheral venous cutdown is an excellent technique for rapid fluid or blood product infusion in the emergent setting. This is usually performed when other methods of venous access are unavailable or have failed. It is a relatively simple procedure. If learned properly, it can be lifesaving in the critically ill or injured patient. It is imperative to understand the relevant local anatomy and identify the clinical landmarks before this procedure is performed. Strict adherence to sterile technique and the early removal of the catheter will decrease the rate of infection and complications.
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Intraosseous Infusion Amanda Munk and O. John Ma
INTRODUCTION Obtaining peripheral vascular access in the critically ill patient may be difficult and time-consuming. The vascular collapse that may accompany severe dehydration or a cardiac arrest can be profound and delay administration of essential therapies. Pediatric patients, in particular, may present a challenge due to the small size of their peripheral veins and the increased subcutaneous tissue. Administration of endotracheal medications may not provide rapid and reliable drug absorption during a cardiorespiratory arrest.1,2 Intraosseous (IO) access was first described in 1922 by Dr. Drinker. He referred to the medullary cavity as a “non-collapsible vein” that can be used for obtaining rapid vascular access. IO access for pediatric use was introduced in 1941. The first IO blood transfusion was documented in1942. The IO route of venous access did not become popular for many reasons. The equipment at the time was crude and did not improve until the 1970s. The technique of a saphenous venous cutdown was soon developed as an alternative method for obtaining vascular access. The development of plastic, disposable, and single use intravenous (IV) catheters revolutionized the technique of IV access. IO access is an alternative route for blood, drug, and fluid administration. This previously abandoned technique was reintroduced in the mid-1980s in response to the need for more immediate vascular access during cardiopulmonary resuscitation.3,4 This procedure has focused on pediatric patients due to the increased difficulty and necessity of access in critically ill children. Studies have demonstrated that peripheral venous access during pediatric cardiac arrest constituted the most expeditious manner of obtaining vascular access (mean time of 3.0 minutes). However, it was only successful in 17% of patients. This was in stark contrast to the 83% success rate for IO lines, 81% for peripheral venous cutdowns, and 77% for central venous lines.5,6 The time required to place an IO line was 4.7 minutes compared to 8.4 minutes for a central venous line and 12.7 minutes for a peripheral venous cutdown. The insertion of an IO line was recently studied in the prehospital arena, where it was shown to be safe and effective.7,8 IO infusion is also quick, safe, and effective in compromised neonates.9 IO access has been increasingly used in the resuscitation of adult patients when vascular access is unobtainable.10,11 For prehospital providers, IO access has proved to be an invaluable procedure. One national prehospital study noted success rates for IO placement at 91%, with the majority of patients being adults.12 In adults over the age of 80 years, success rates neared 97%. The newer powered devices make penetrating the adult cortical bone much less difficult.12
ANATOMY AND PATHOPHYSIOLOGY Long bones are composed of a dense outer cortex and inner soft, spongy (cancellous) bone (Figure 55-1). The nutrient artery supplies the bone with a rich vascular network. It pierces the cortex and divides into ascending and descending branches that further divide into arterioles and then capillaries. Venous drainage from the capillaries into the medullary venous sinusoids, located at the proximal and distal portions of the long bone, flows into the central venous channel located in the shaft of the long bone.13 The IO needle is inserted through the cortex and into the bone marrow (medullary) cavity of a long bone. Numerous anatomic sites can be used to access the medullary cavity. The most traditional
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Distal tibia
Epiphysis Growth plate
X
Greater saphenous vein
Medial malleolus
Intraosseous needle
Medullary venous sinusoids
Emissary veins
Central venous canal
Nutrient vein
FIGURE 55-3. The distal tibia is one of the preferred sites for IO access in adult patients. The ⊗ represents the site of IO needle insertion.
FIGURE 55-1. Venous anatomy of a long bone.
INDICATIONS site, which is favored in pediatric patients, is the flat anteromedial surface of the proximal tibia (Figure 55-2). The distal tibia just above the medial malleolus is the preferred site in adult patients (Figure 55-3). In the adult, it is easier to penetrate the cortex of the medial malleolus than the thicker cortex of the proximal tibia. Other sites for IO access include the flat anterior surface of the distal femur (Figure 55-4) and the anterolateral surface of the proximal humerus (Figure 55-5).14 Crystalloid infusion studies through an IO line in animals have demonstrated an infusion rate of approximately 10 to 20 mL/min with gravity and up to 40 mL/min under pressure.15,16 Fluids and medications administered through an IO line are immediately absorbed into the systemic circulation. Sodium bicarbonate infusion, even during a cardiac arrest, was shown to have superior buffering capacity when administered via an IO line than by a peripheral IV line.17 Medications and fluids that may be administered by the IO route are listed in Table 55-1.18,19 The medication concentrations, dosages, and infusion rates through an IO line are the same as those through a peripheral IV line. Succinylcholine has been effectively infused by the IO route for muscle paralysis prior to endotracheal intubation.20
The placement of an IO line is indicated when vascular access is rapidly required for the resuscitation of a patient and standard vascular access is unobtainable or delayed. It may be operationally useful to define a specific time frame or a specified number of peripheral IV attempts before proceeding to IO access. Situations that may require the placement of an IO line are cardiac arrest, shock, sepsis, trauma, severe dehydration, extensive burns, status epilepticus, or any condition that requires urgent administration of fluids, medications, or blood products.18 Current American Heart Association Advanced Cardiac Life Support guidelines recommend IO access if IV access is unobtainable within 90 seconds or two attempts and for the administration of medications over endotracheal medication administration. In addition to resuscitation, IO access can provide blood samples for typing, crossmatching, and laboratory analysis. Electrolytes, creatinine, blood urea nitrogen (BUN), glucose, calcium, and arterial blood gas values from blood samples obtained through an IO needle
Medial condyle Tibial tuberosity 2 cm
X
X
Flat anteromedial surface of proximal tibia
2 cm Lateral condyle
Medial condyle
Patella FIGURE 55-2. The proximal tibia is the traditional site used in pediatrics for IO access. The ⊗ represents the site of IO needle insertion.
FIGURE 55-4. The distal femur is an alternative site for IO access. The ⊗ represents the site of IO needle insertion.
CHAPTER 55: Intraosseous Infusion
FIGURE 55-5. The proximal humerus is an alternative site for IO access in the adult. The ⊗ represents the site of IO needle insertion.
are similar to those from samples taken via traditional routes.21,22 Laboratory values may be less accurate after five or more minutes of active resuscitation, or if drugs or fluid have been infused through the IO site.22
CONTRAINDICATIONS Placement of an IO line is contraindicated in diseased or osteoporotic bone. The placement of an IO line through areas of cellulitis, abscesses, or burns should be avoided.23 Fractures in the ipsilateral bone increase the risk of an extravasation-induced compartment syndrome and nonunion of the fractures.24 Failed placement of an IO line in the same bone is a relative contraindication. Do not use a bone that has had a previous orthopedic procedure, contains hardware, or may contain hardware (i.e., pins, plates, screws, and artificial joints). An IO line should not be inserted if the patient is morbidly obese as the needle is too short to enter the medullary cavity or if the patient is so obese that the bony landmarks cannot be palpated. There are contraindications specific to sternal IO access. Do not attempt sternal IO access in patients who weigh less than 50 kg, are small in stature, have a small sternum, have congenital sternal malformations, or have chest wall malformations. The blunt trauma patient with a suspected sternal fracture or soft tissue injury over the sternum should not be considered for sternal IO access. A history of a sternotomy or osteoporosis is also a contraindication.
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TABLE 55-1 Medications and Fluids that may be Administered Through an IO Line16–19,43,44 Medications Adenosine Diazoxide Lorazepam Amiodarone Digoxin Mannitol Antibiotics Dobutamine Morphine Antitoxins Dopamine Naloxone Anesthetics Ephedrine Norepinephrine Atracurium besylate Epinephrine Pancuronium Atropine Heparin Phenobarbital Calcium gluconate Insulin Phenytoin Calcium chloride Isoproterenol Propranolol Contrast media Ketamine Sodium bicarbonate Dexamethasone Levarterenol Succinylcholine Diazepam Lidocaine Tenecteplase Thiopental Vecuronium Fluids Blood products Dextrose solutions Iodinated contrast agents Lactated Ringer’s solution Packed red blood cells Plasma Sodium chloride solutions
• Plastic protective cup • Leg board for immobilization • IO access device IO needles are available in a number of sizes and styles (Figure 55-6). Only specifically designed IO needles should be used for this procedure. Spinal needles often bend and do not penetrate the cortex of the bone. Their long length causes increased resistance to fluid flow. Standard hypodermic needles also often bend and do not penetrate the cortex of the bone. Both these types of needles may break while being inserted and injure the healthcare provider. Available models of manually inserted IO devices include the hand-driven threaded-needle SurFast and Cook Intraosseous needle (Cook Critical Care, Bloomington, IN), the Jamshidi bone marrow needle (Baxter Healthcare, Valencia, CA), and the MedSurg Industries Illinois sternal/iliac aspiration needle (MedSurg Industries, Rockville, MD). The typical unit consists of a detachable
EQUIPMENT • • • • • •
Sandbag or towels Povidone iodine or chlorhexidine solution Local anesthetic solution, 1% or 2% lidocaine Syringe, 5 to 60 mL Primed intravenous tubing with normal saline Tape
FIGURE 55-6. IO infusion needles. From left to right: the Cook Intraosseous infusion needle, two models of the Illinois sternal/iliac aspiration needle, and the Jamshidi bone marrow needle.
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A FIGURE 55-8. The BIG in adult and pediatric sizes (Photo courtesy of Wais Medical, Houston, TX).
the manual devices. They are easier to use, quicker to establish IO access, require less or no force to insert the IO needle, and do not bend during insertion. Sternal access devices include the MONOJECT I-Type SternalIliac Aspiration Needle (Covidien, Mansfield, MA), the First Access for Shock and Trauma (FAST1 and FASTX , Pyng Medical, Richmond BC), and Life/form® Adult Sternal Intraosseous Infusion System (Nasco, Modesta, CA). The F.A.S.T.1 is a multiple-component kit to be used for sternal IO access in the adult patient. A special introducer limits the depth to which the needle can be inserted. This prevents injury to the underlying great vessels, heart, lung, and mediastinum. This system was evaluated in Special Forces military settings, and found to be equally useful and safe in terms of IO access.27 Sternal IO access devices are used less often than the previously described powered devices due to the possible interference with resuscitation attempts and their incomplete removal on occasion requiring surgical removal.
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PATIENT PREPARATION B FIGURE 55-7. The EZ-IO. A. The driver and three lengths of IO needles. B. The EZ-Stabilizer (Photos courtesy of Vidacare, San Antonio, TX).
handle, an IO needle, an obturator, and a sleeve to prevent the needle from penetrating too deeply. The IO needle ranges in size from 12 to 20 gauge. The IO needles available today are variations of the basic unit and include adjustable-length shafts to decrease the risk of penetrating too deeply, a variety of tips on the obturator (e.g., lancet, pencil point, and trocar), threaded versus nonthreaded shafts, needle side ports to increase flow rates, numerous lengths, and numerous handle types. New powered and spring loaded injection devices have evolved. Two currently available devices are the EZ-IO Intraosseous Driver (Vidacare, San Antonio, TX) and the Bone Injection Gun (BIG, Wais Medical, Kress USA Corporation). The EZ-IO uses a batterypowered driver to insert the needle to a preset depth (Figure 55-7).14 The BIG incorporates a loaded spring to inject the IO needle, and the desired depth of injection may be adjusted (Figure 55-8).25 Both devices are available in adult and pediatric needle sizes. The EZ-IO and the BIG have numerous advantages when compared to
Explain the procedure, its risks, and benefits to the patient and/or their representative if time permits. This procedure is often performed in emergencies; therefore, informed consent can often be waived. Currently, the primary site of choice for IO line placement is the proximal tibia. Alternate sites include the distal tibia, distal femur, proximal humerus, and the sternum. Even with sternal access, it is possible to perform a cricothyroidotomy and cardiopulmonary resuscitation (CPR).25 The proximal humerus allows more central access, while the proximal tibia is often accessible without disrupting airway management and CPR.14 Place the patient supine with the lower extremity supported behind the knee with a towel or sandbag. Identify by palpation the landmarks required to perform the procedure. Palpate the bony landmarks with the nondominant hand. The bony landmarks for the proximal tibia approach are the tibial tuberosity and the flat anteromedial surface of the proximal tibia. The site of IO needle placement is approximately 2 cm below the tuberosity on the flat anteromedial surface of the proximal tibia (Figure 55-2). The bony landmark for the distal tibia approach is the junction of the medial malleolus and the flat anteromedial surface of the distal tibia just posterior to the greater saphenous vein18 (Figure 55-3). This is the preferred site in the adult patient. The bony landmarks for the distal femur approach are the medial and lateral condyles of the femur
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FIGURE 55-9. Placement of an IO line. A. The nondominant hand is used to support the extremity. The IO needle is inserted with a twisting motion to cut through the cortex of the bone. B. The handle and obturator are removed. C. A syringe is attached to the hub of the IO needle and bone marrow is aspirated.
and the patella. The IO needle should be positioned approximately 2 cm above these structures (Figure 55-4). This site is utilized less often due to the abundance of muscle and soft tissue structures. The bony landmarks for the humeral approach are slightly anterior to the lateral midline of the arm, with care to avoid the bicipital groove (Figure 55-5). The arm should be adducted and internally rotated for optimal positioning.14 Prepare the patient. Clean any dirt and debris from the skin. Apply povidone iodine or chlorhexidine solution to the skin and allow it to dry if time permits. This procedure is extremely painful. If time permits, the use of a local anesthetic solution in the conscious or semiconscious patient will be greatly appreciated. Infiltrate local anesthetic solution into the skin, subcutaneous tissues, and periosteum overlying the bone puncture site. Additionally, in the alert patient, consider infusing 3 to 5 mL of 2% lidocaine intravenously both initially and at regular intervals to minimize patient discomfort.11
TECHNIQUE MANUALLY INSERTED IO DEVICES Examine the IO needle to ensure that it appears to have been manufactured properly. Reidentify the landmarks with the nondominant hand. Stabilize the extremity with the nondominant hand (Figure 55-9A). Grasp the IO needle firmly with the dominant hand. The handle of the IO needle should be firmly planted in the palm of the dominant hand. Insert the needle perpendicularly or slightly angulated (at a 10° to 15° angle) to the long axis of the bone (Figure 55-9). The IO needle should always be directed away from the growth plate to avoid injuring it. Direct the needle caudad in the proximal tibial approach and cephalad in the distal tibial and distal femoral approaches.
Advance the IO needle through the skin and subcutaneous tissue until the bone is contacted. Advance the IO needle through the bone. A twisting or rotary motion with the simultaneous application of downward pressure should be used to cut through the cortex of the bone (Figure 55-9A). A significant reduction in the resistance to forward motion will be encountered when the cortex is penetrated and the needle enters the medullary canal. This distance is rarely greater than 1 cm in most patients. An index finger may be placed 1 cm from the bevel of the IO needle prior to advancement. This will help prevent overpenetration into and through the cortex on the opposite side of the bone.28 Alternatively, adjust the sleeve so that only 1 cm of the IO needle is exposed. Stop advancing the IO needle when it enters the medullary canal. Remove the stylet when the medullary canal is entered (Figure 55-9B). Attach a 5 or 10 mL syringe onto the hub of the IO needle (Figure 55-9C). Aspirate blood from the medullary canal to confirm proper placement of the IO needle. Any samples obtained may be sent to the laboratory for subsequent analysis. The aspiration of more than 2 to 3 mL of blood may not be possible in cardiac arrest situations. Attach IV tubing to the hub of the IO needle and begin the infusion of fluids. Medications can be administered through the injection port of the IV tubing. Place a sterile dressing around the skin puncture site and apply pressure for 5 minutes.29
IO ACCESS USING THE EZ-IO The EZ-IO is a reusable, nonsterile, battery powered driver that uses sterile, disposable, single patient use IO needles. The IO needles are available in three lengths (15, 25, and 45 mm). Choose the proper IO needle for the patient, their body habitus, and the insertion site. Assess the tissue depth by palpation. Choose an IO needle so that at least one black line on the IO needle shaft will be
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SECTION 4: Vascular Procedures
A
B
C
D
E
above the patient’s skin when the tip is against the bone. The IO needle tip is designed to cut the bone and create a hole the same size as the needle. Identify the IO insertion site and prepare for the procedure. Clean and prep the skin at the site and surrounding area. The procedure requires aseptic technique. Select the appropriate size IO needle. Open the cover of the case that holds the sterile IO needle. Insert the bit on the EZ-IO driver into the base of the IO needle (Figure 55-10A). Leave the cap on the IO needle until it is ready to be inserted. Open the EZ-Connect tubing and flush it with a
FIGURE 55-10. Using the EZ-IO. A. An IO needle has been applied onto the driver. B. Insert the IO needle at a 90° angle to the skin. C. The driver has been removed. D. The stylet is removed. E. The EZ-Stabilizer and tubing have been applied.
syringe containing 10 mL of sterile normal saline. Leave the syringe attached to the tubing after it is flushed. Reidentify the landmark for the insertion site. Inject local anesthetic solution subcutaneously and down to the periosteum. Remove the cap from the IO needle. Insert the IO needle perpendicular or at a 90° angle to the skin (Figure 55-10B). Advance the IO needle through the skin and subcutaneous tissues until the tip is against bone. At least one black line on the needle shaft should be visible above the patient’s skin. If a black line is not visible on the needle shaft, withdraw the needle and replace it with a longer
CHAPTER 55: Intraosseous Infusion
IO needle. Press the trigger to start the driver shaft and IO needle rotating. Apply gentle and minimal downward pressure to advance the IO needle into the medullary canal. Stop advancing the driver when a loss of resistance is felt. Grasp and firmly hold the hub of the IO needle. Remove the driver (Figure 55-10C). Do not allow the IO needle to move while removing the driver. Twist the stylet counterclockwise and remove it while securely holding the IO needle hub (Figure 55-10D). Attach the EZ-IO stabilizer (Figures 55-7B & 55-10E), if using it, followed by the primed EZ-Connect tubing. Aspirate bone marrow to confirm proper needle placement. Do not attach a syringe directly to the IO needle hub. A syringe attached to the hub can result in a fracture of the hub. Always attach the EZ-Connect tubing then aspirate and inject through it and not directly through the IO needle hub. Begin using the IO access.
IO ACCESS USING THE BIG The BIG is an automatic, spring loaded device that does not require a power source. It is available in two sizes, adult and pediatric. The
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insertion site is different for adults and children. Always start at the tibial tuberosity as the initial landmark. For adults, move 2 cm medially toward the inner leg and then 1 cm proximally toward the patient’s head. For children, move 1 to 2 cm medially toward the inner leg and then 1 to 2 cm distally toward the patient’s foot. Mark this final location as the insertion site. It may also be inserted in the proximal humerus in the adult patient. Prepare for the procedure. This procedure requires aseptic technique. Clean and prep the skin at the insertion site and surrounding area. Open the package and remove the sterile BIG. Rotate the base of the unit to adjust the IO needle penetration depth according to the pediatric patient’s age: 0 to 3 years at 0.5 to 1.0 cm, 3 to 6 years at 1.0 to 1.5 cm, and 6 to 12 years at 1.5 cm (Figure 55-11A). Use the adult BIG for patients over the age of 12 years. Reidentify the landmark for the insertion site. Inject local anesthetic solution subcutaneously and down to the periosteum. Position the BIG at the insertion site with the base perpendicular or at 90° to the skin (Figure 55-11B). Firmly grasp the BIG with the nondominant hand. Squeeze and pull out the red safety latch while firmly holding the BIG against the insertion
A
B
C
D
FIGURE 55-11. Using the BIG. A. Adjust the penetration depth. B. Apply the BIG at a 90° angle to the skin. C. Remove the safety latch. D. Grasping the BIG in preparation of triggering the unit.
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SECTION 4: Vascular Procedures
E
F
G
H
FIGURE 55-11. (continued ) E. Remove the BIG. F. Attach and secure the safety latch. G. Pull the stylet-trocar from the IO cannula. H. Attach IV tubing onto the hub and aspirate bone marrow (Photos courtesy of Wais Medical, Houston, TX).
site (Figure 55-11C). Do not discard the safety latch as it will be used later to secure the IO needle. Grasp the upper part of the BIG with the dominant hand (Figure 55-11D). Place two fingers under the wings and the palm on the top of the BIG (Figure 55-11D). Continue to firmly hold the base against the patient’s skin with the nondominant hand. Insert the IO needle. Trigger the BIG by gently pressing down with the palm. The device will eject the spring loaded IO needle into the bone. The IO needle should be standing upright, firmly in the bone, and stable. If not, it has been placed into muscle or soft tissue. Gently lift and remove the BIG device without catching on the IO needle hub (Figure 55-11E). Attach the safety latch onto the cannula between the patient’s skin and the IO cannula hub (Figure 55-11F). Secure the safety latch to the skin with tape (Figure 55-11F). Gently remove the stylet-trocar, leaving the cannula in place (Figure 55-11G). If the stylet-trocar is “stuck” and not easily removable, do not pull or try to forcefully remove it. The IO needle did not penetrate all the way into the medullary cavity and is embedded in the cortex. Insert the square end of the safety latch into the hub of the IO needle and
gently twist to remove the IO needle. Repeat the procedure at another site. Attach the IV tubing onto the hub of the cannula (Figure 55-11H). Aspirate bone marrow to confirm proper placement (Figure 55-11H). Flush the IV tubing and cannula with 5 to 10 mL of sterile saline. Begin using the IO access.
ASSESSMENT Assess whether the IO needle is correctly positioned within the medullary cavity. First aspirate blood from the marrow cavity. This may not be possible because of poor circulation in patients with a cardiac arrest. A second sign of correct placement is to assess whether the IO needle will stand erect without support. Finally, flush the IO line. The ability of the fluid to flow without inducing soft tissue swelling can also be used to confirm proper placement. Ultrasonic visualization of flow within the medullary cavity using color flow Doppler can also confirm proper placement.45 A reassessment must be performed again at regular intervals to ensure that extravasation does not occur.30 Circumferential pressures of the involved extremity may be used for serial examination.30
CHAPTER 56: Umbilical Vessel Catheterization
A C-arm fluoroscopic imaging device may be used at the bedside to confirm accurate placement of the IO needle.31
AFTERCARE Secure the IO needle. Secure the manually inserted IO needle by taping it in place. It may be easier to apply 4 × 4 gauze squares on two sides of the IO needle to support it and then tape the needle and gauze in place. Secure the EZ-IO needle in the same manner. Tape the safety latch of the BIG to the skin to secure it. Tape the IV tubing securely at several points. This will prevent traction on the tubing from pulling the IO needle out of the bone. Tape a plastic cup over the IO needle to avoid inadvertent disruption during patient resuscitation or positioning. Immobilize the extremity, if necessary, to help secure the IO line. Remove the IO line once the resuscitation is complete and another form of secure vascular access has been obtained. Manually inserted IO devices can be removed by gently twisting it and pull it straight out. Do not rock the device. To remove the EZ-IO, attach a 5 or 10 mL Luer lock syringe onto the IO needle hub. Rotate the syringe clockwise and pull it straight out. It may take several rotations of the syringe before the IO needle can be removed. Do not rock the IO needle or syringe. To remove the BIG cannula, insert the square end of the safety latch into the hub of the cannula and gently twist and pull to remove it. Bleeding at the insertion site can be controlled with a sterile pressure dressing followed by cleansing the skin and a simple bandage.
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The complications specific to the EZ-IO include hub fracture after insertion and separation of the needle from the hub upon removal. Too much downward pressure upon IO needle insertion can result in it penetrating the back of the bone. The other general complications are described above. The complications associated with the BIG are primarily from incorrect use. Never remove the safety latch until the BIG is against the patient’s skin over the insertion site. Removal of the safety latch activates the device. The IO needle can be forcefully ejected and injure someone if the BIG is squeezed after the safety latch is removed. Never place a finger over the distal end of the BIG. Always grasp the BIG properly. Grasping it upside down can result in the IO needle penetrating the Emergency Physician’s hand. Incorrectly adjusting the penetration depth can result in the IO needle penetrating the back of the bone. The other general complications are described above.
SUMMARY The placement of an IO line is a viable option in the resuscitation of a patient when traditional vascular access techniques have failed. The procedure is technically straightforward and has been demonstrated to be successful in the hands of trained healthcare workers, including prehospital personnel. Complications have been related mostly to technical mistakes and can be avoided if care is taken to correctly identify landmarks, avoid the growth plate, regulate the depth of IO needle placement, and ensure the early removal of the IO line.
COMPLICATIONS The most common complication of IO infusions are subcutaneous and subperiosteal extravasation of fluid due to technical difficulty.4 Under ideal circumstances, the type of IO needle used should not affect extravasation rates.30,32 Extravasation is usually due to underor overpenetration of the cortex. There have been cases of tibial fracture due to overpenetration of the cortex.33,34 A compartment syndrome may occur when there is extravasation or when IO lines are placed in fractured bones.26 Necrosis and sloughing of the skin at the insertion site of the IO needle are due to extravasation of fluid or medication.35 Localized infections may occur after IO needle placement. Cellulitis or the formation of subcutaneous abscesses occur in 0.7% of patients.24 Osteomyelitis has been reported in less than 1% of patients with IO needles.25 Risk of osteomyelitis increases with prolonged IO use, administration of hypertonic fluids, and bacteremia.25,36 Injury to the growth plate is a commonly mentioned complication; however, the literature does not support this.37,38 Additionally, in recent animal studies, the rate of the IO infusion and the osmolarity of the infused fluid did not adversely affect the bone marrow or bone development.42 Fat embolism has also been mentioned as a possible complication.41 Consider a fat embolism if the patient becomes hypoxic or experiences respiratory difficulty shortly after beginning an IO fluid infusion or bolus. The use of an IO line for the infusion of emergency drugs and fluids does not increase the magnitude of fat embolization during CPR.39,40 Animal studies have shown no significant increase in fat emboli in lung tissue when IO infusion is used.39 The flow rate of fluid through an IO line is slower than that through a peripheral intravenous line. This may be due to a small marrow cavity, a fibrous marrow cavity, and/or the replacement of red marrow with yellow marrow. Fluid flow rates can be significantly increased by applying a pressure bag onto the intravenous fluid bag or using a level-one infuser. The placement of a second IO line may be required to further increase the amount of fluid that can be infused.
56
Umbilical Vessel Catheterization Eric F. Reichman, Amy Noland, and Antonio E. Muñiz
INTRODUCTION Umbilical vessel catheterization was first described by Diamond in 1947 for an exchange transfusion in a neonate.1 Umbilical vessel catheterization serves many important functions in the ill neonate. Umbilical vessel catheterization can be used as a reliable method of obtaining rapid vascular access in the neonate. Umbilical vessel catheters may be used for fluid resuscitation, blood transfusion, medication administration, frequent blood sampling, and cardiovascular monitoring.2–5 However, the use of these catheters also carries significant risk of permanent morbidity and even death. Either the umbilical artery or vein may be used for vascular access. The artery can usually be accessed within the first 24 hours of life. It is occasionally possible to use the umbilical artery up to 7 days after birth.2 The umbilical vein can be accessed for up to 2 weeks of age.2,6 Umbilical artery catheterization is more desirable than umbilical vein catheterization because it allows frequent arterial blood gas sampling and continuous blood pressure monitoring, in addition to fluid, blood, and medication administration. Unfortunately, umbilical artery catheterization is more difficult and time consuming to perform, especially in unskilled hands. Therefore, umbilical vein catheterization is the preferred procedure for the infant in shock and in need of rapid resuscitation. Arterial access can be obtained later in a more controlled environment, such as in the neonatal intensive care unit. Umbilical vessel catheterization can lead to serious complications and
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SECTION 4: Vascular Procedures
Ductus arteriosus
Foramen ovale
Inferior vena cava Descending aorta Ductus venosus Umbilical cord
Urachus
External iliac artery Internal iliac artery
Umbilical arteries Umbilical vein Placenta
FIGURE 56-1. The fetal circulation.
should be reserved for the patient in whom peripheral venous access attempts have been unsuccessful.5,7
ANATOMY AND PATHOPHYSIOLOGY The fetal circulatory system is quite different from that of the neonate or infant (Figure 56-1). Oxygenated blood from the placenta travels via the umbilical vein, through the ductus venosus in the liver, to the inferior vena cava (IVC), and into the right atrium. Oxygenated blood from the IVC preferentially enters the left atrium through the foramen ovale. It then enters the left ventricle, then the aorta. This oxygen-rich blood supplies the brain prior to mixing with the oxygen-poor blood coming through the ductus arteriosus. Deoxygenated blood from the superior vena cava (SVC) enters
the right ventricle and is pumped to the pulmonary artery. It then passes through the ductus arteriosus to meet the oxygenated blood in the aorta. Pulmonary vascular resistance decreases dramatically as the infant takes its first breaths. The systemic vascular resistance increases when the umbilical cord is clamped. The foramen ovale closes with the combination of decreased pulmonary artery pressure and increased systemic resistance. The ductus arteriosus closes within 24 to 48 hours due to the release of prostaglandins and increased blood oxygen tension. The ductus venosus closes when the umbilical cord is clamped. The umbilical vein and arteries can easily be differentiated by examination of a cross section of the umbilical cord (Figure 56-2). The umbilical vein is a single vessel with thin walls and a large
CHAPTER 56: Umbilical Vessel Catheterization
FIGURE 56-2. Anatomy of the umbilical cord.
lumen. It is usually flattened in one direction. There are two thickwalled umbilical arteries that are significantly smaller in diameter than the umbilical vein. Occasionally, only a single umbilical artery is present.
INDICATIONS Umbilical artery catheterization is indicated when frequent arterial blood gas determinations and continuous monitoring of blood pressure are required in the first few days of life in critically ill neonates.4 Umbilical artery catheters can be used for delivering blood, fluids, total parenteral nutrition, medications, and for exchange transfusions.2,3 It reduces the need for multiple venipunctures and heel prick capillary blood sampling in the critically ill neonate.8 Neonates under 24 hours of age can usually be catheterized without much difficulty. Skilled Emergency Physicians can sometimes perform this in neonates up to 7 days of age.2 Umbilical vein catheterization is easier to perform than umbilical artery catheterization. It is the preferred procedure for the neonate in shock needing rapid administration of intravenous fluids, blood, or medications.1 In critically ill neonates, the umbilical vein can be used to monitor central venous pressure. This procedure is possible in neonates up to 2 weeks of age.2 Recently, the umbilical vein has been used to perform invasive cardiac procedures.9
CONTRAINDICATIONS Umbilical vessel catheterization in the Emergency Department should be performed only on severely ill neonates in whom peripheral vascular access attempts have failed. The contraindications are similar for the umbilical vein and umbilical artery catheterization. These include gastroschisis, an omphalocele, omphalitis, and peritonitis.2,10 Never insert an umbilical catheter if there are any signs of infection on or around the remnant of the umbilical cord. Umbilical vessel catheterization is contraindicated if a neonate is older than the previously stated ages. An alternate route of vascular access is required if the possibility of an abdominal abnormality exists, as manifested by a distended abdomen or visible defects.2 Relative contraindications for placement of an umbilical artery catheter include decrease perfusion to the lower extremities or buttock and suspicion of necrotizing enterocolitis.
EQUIPMENT • • • •
Umbilical vein catheters, 5.0 French and 3.5 French Umbilical artery catheters, 5.0 French and 3.5 French Umbilical tape Povidone iodine or chlorhexidine solution
• • • • • • • • • • • • • • • • • •
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Sterile gauze Sterile drapes Sterile gown and gloves Cap and face mask Adhesive tape Radiant warmer with a light Cardiac monitor Pulse oximeter 3-0 or 4-0 silk suture with a needle Needle driver Smooth-curved iris forceps Iris scissors Two small, smooth-curved hemostats Straight Crile forceps #10 or #11 scalpel blade on a handle Three-way stopcock 10 mL syringe filled with normal saline Heparinized sterile saline solution, 1 unit of heparin/1 mL of saline
Umbilical artery and vein catheters are available in a variety of sizes. Umbilical vein catheters are available as a single-lumen or double-lumen catheter. They should not have side holes unless it is to be used specifically for an exchange transfusion. Use a 5.0 French umbilical venous catheter in neonates weighing >1200 g and a 3.5 French catheter in neonates weighing 3500 g and a 3.5 French catheter in neonates weighing 6 h Wound depth >1 cm Wound type Abrasion, avulsion, crush, irregular, stellate
Non-tetanus-prone wounds Absent Absent Absent Absent Sharp and smooth (knife or glass) 2 cm DPC if 2 cm DPC if 2 cm DPC if 2 cm DPC if 2 cm DPC if 2 cm DPC if 2 cm DPC if 2 cm DPC if 50, diabetes, alcoholism, asplenia, and patients with any other illness associated with an impaired immune status.
Consult the local public health department for guidelines and the incidence of rabies in your community. The discharge instructions are just as important as the Emergency Department management. Provide the patient with a written copy of a wound care sheet, regardless of whether the wound was closed primarily. Instruct the patient to elevate any involved extremity, even with antibiotic treatment.66 Arrange follow-up within 24 to 48 hours for a reevaluation of the wound. Physical therapy following a hand infection may be required and initiated 3 to 5 days after the infection resolves.59
DEBRIDEMENT OF GUNSHOT WOUNDS The lack of primary literature on this subject makes it a controversial area. Wounds created by low-velocity bullets tend to cause damage only along the bullet track. Debridement is unnecessary for wounds created by bullets with muzzle energy of less than 400 foot-pounds, as many consider bullets to be sterile.67 Devitalized and contaminated tissue are more likely to result from shotgun wounds and high-velocity bullets.68 The shock wave created by the bullet damages tissue distant from the track of the bullet.68 Consider these wounds for debridement.68 The debridement of gunshot wounds requires exposure of the entire bullet track and treatment as a delayed closure, followed by referral for skin grafting if needed. Clean, prep, and anesthetize the skin overlying the path of the bullet (or shotgun blast). Incise the wound with a #11 scalpel blade to expose the area. Sharply debride any devitalized and contaminated tissue. Repeated staged exploration should be undertaken at 24 and 48 hours to remove necrotic or devitalized tissues.69 Treat with prophylactic antibiotics; cefazolin, 1 g intravenously every 8 hours, is satisfactory.69 Treat the area with delayed closure techniques, giving priority to reestablishment of bony relationships, followed by soft tissue coverage.69 Consider skin grafting for large areas of tissue destruction for adequate closure.
ABRASIONS An abrasion is a skin wound created by tangential trauma to the epidermis and dermis. The skin is forced against an abrasive surface in a rubbing fashion and the resultant injury resembles a thermal burn. The goals of managing an abrasion include the prevention of infection, promotion of healing, and prevention of “tattooing” with retained foreign bodies. Large and heavily contaminated abrasions are best managed in the operating room, as the volume of local anesthetic required to achieve anesthesia would likely exceed toxic limits. Prepare the wound. Anesthesia may be required prior to wound management. EMLA cream, which contains lidocaine and prilocaine, produces anesthesia of the intact skin but it must be in place for about 60 minutes in order to provide significant benefit.70 Perform a field block or regional nerve block (Chapter 126) as appropriate. Large abrasions may be anesthetized by applying 5% lidocaine gel topically for 5 to 10 minutes. Remove any dirt or debris, using a sterile scrub brush and surgical soap (or saline). Consider imaging (i.e., plain radiographs) to evaluate for potential foreign bodies.28 Use the tip of a #11 scalpel blade to remove deeply embedded and larger particles from the wound. Apply petroleum jelly or antibiotic ointment to remove embedded tar.71 Apply an antibacterial ointment to the wound. Instruct the patient to cleanse the wound three to four times a day. The wound may also be covered with petrolatum gauze and sterile gauze. Instruct the patient on how to properly cleanse the wound and reapply the bandage. Provide the patient with wound care supplies prior to discharge from the Emergency Department.
CHAPTER 97: Subcutaneous Foreign Body Identification and Removal
97
Subcutaneous Foreign Body Identification and Removal Samuel J. Gutman and Michael B. Secter
INTRODUCTION Wounds with retained foreign bodies are a frequent presenting complaint to Emergency Departments. Up to 38% of embedded objects are missed on the initial assessment.1 Identification and removal of debris and foreign bodies promote optimal healing of traumatic wounds. The presence of an unrecognized foreign body can lead to complications that include infection, pain, loss of function, joint injury, tenosynovitis, tendon rupture, and osteomyelitis.2–5 Patients presenting with chronic, recurrent, or delayed skin infections should be assessed for the presence of an unrecognized foreign body. Failure to diagnose and treat a foreign body is a common cause of litigation against Emergency Physicians. The presence of a foreign body may not be obvious. A high index of suspicion and careful methodical examination, including appropriate imaging, must be undertaken to identify a foreign body. It is important to be familiar with the characteristics of different types of foreign bodies and the interactions they may have with a host patient. This information is crucial in determining the urgency or necessity of removal (not all implanted objects require removal), the appropriate imaging techniques, the approach to removal, and whether specialty referral is required. The removal of foreign bodies from subcutaneous tissue can be a frustrating and time-consuming endeavor when it is ill conceived. The successful removal of a foreign body requires a directed history and physical examination, appropriate imaging, adequate light, anesthesia, exposure, hemostasis, patient cooperation, an uninterrupted time period for attempted removal, appropriate wound care, and assured postprocedural follow-up.
ANATOMY AND PATHOPHYSIOLOGY Only a small percentage of wounds actually contain concealed foreign bodies.6 The mechanism of injury may give some idea of the likelihood of a retained object.1 Crush wounds and puncture wounds, especially those involving the sole of the foot, as well as wounds deeper than 5 mm involving adipose tissue are associated with a higher incidence of foreign bodies that are often difficult to find.6 Wounds caused by objects that shatter, splinter, or break in the process of causing injury have a higher risk of having a retained foreign body.7 Lip or facial lacerations associated with dental fractures must be explored for pieces of teeth. Thorns, spines, or slivers tend to penetrate deeply and break. Broken-off needles are common foreign bodies in injection drug users. Objects greater than 4.5 mm in diameter that penetrate the skin may push fragments of epidermis deep into the wound producing an epidermal inclusion cyst, which can act as a foreign body.8 Depending upon the type of material retained and the physical form of the foreign object, excess inflammation may result. This can delay healing or destroy surrounding soft tissues. Retained organic foreign bodies trigger the most severe inflammatory reactions and can lead to chronic granulomatous reactions, periosteal reactions, osteolytic lesions, or severe infections such as necrotizing fasciitis.8–10 The presence of soil in wounds markedly lowers the concentration of bacteria required to cause an infection by its interaction and interference with white blood cells.11 Wounds tend to be resistant to antibiotics when a foreign body is present2,3,12 and
669
it may be impossible to eradicate the infection until the foreign body is removed.2,3,12 Metals that oxidize may cause mild to moderate inflammation. Some retained foreign bodies, like lead, have the potential to produce systemic effects, especially when in contact with pleural, peritoneal, cerebrospinal, or joint fluid.13 Inert objects with smooth, nonporous surfaces like glass or plastic elicit minimal tissue reaction. Retained foreign bodies that are not dissolved or extruded by the body’s defenses become encapsulated, after which the inflammation will subside.13
HISTORICAL AND PHYSICAL ASSESSMENT Patients presenting after an injury require a focused history including the details of the incident, the wounding agent, and the mechanism of injury. This information may suggest the presence of a retained foreign body and direct which imaging study is required.14,15 Historical features that may signal unusual circumstances or difficult wound healing and management include diabetes, renal failure, immunosuppression, lymphedema, or peripheral vascular disease.16 Past anesthetic history and the potential for aspiration should be assessed if procedural sedation is to be considered.17 Medications and allergies should be queried. Assess the patient’s tetanus immunization status. Provide booster doses and tetanus immune globulin as needed (Table 92-2). A directed physical examination should begin with a brief inspection and documentation of the distal neurovascular status and function. An injured extremity must be carefully examined through a full range of motion to ensure the integrity of the tendons. Discoloration of the skin may suggest a foreign body.8 Palpation may reveal superficial foreign bodies. Sharp localized pain with palpation over a puncture wound may suggest a retained foreign body. Adequate anesthesia, lighting, and good hemostasis are required to allow a thorough examination of the wound. The examiner must avoid probing only superficially since the subcutaneous tissue can reapproximate and give the appearance of a superficial wound. The wound edges should be extended with a scalpel to facilitate inspection if there is concern regarding a retained foreign body and direct visualization is difficult. A retained foreign body can be ruled out with a negative predictive value of 96% for wounds less than 5 mm deep if the bottom of the wound is visible.6 Never insert a gloved finger to probe the wound cavity, as this can result in injury from sharp foreign bodies. Gentle blind probing with a hemostat is an acceptable and preferred alternative. A grating sensation that can be appreciated by the examiner is produced if the probe strikes a metallic or glass foreign body. Avoid blind grasping within a wound with a hemostat. Direct visualization is preferable when examining wounds of the face, feet, or hands.
RADIOLOGIC ASSESSMENT Imaging is indicated in most cases where a retained foreign body is suspected but not found during wound exploration, when thorough exploration of the entire wound cavity is not possible, or if the patient feels that there is a retained foreign body.
PLAIN RADIOGRAPHY Most foreign bodies missed during the initial clinical examination can be seen on plain radiographs.14 Plain radiographs are readily available. Some authors suggest radiographic evaluation of nearly any penetrating wound involving an extremity.1,4,18 Standard anteroposterior and lateral radiographs should be performed using an underpenetrated “soft-tissue technique” to increase the contrast between the foreign body and the surrounding tissue.3 Visibility of foreign material in
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SECTION 7: Skin and Soft Tissue Procedures
soft tissues is dependent upon its composition, relative density, configuration, size, and orientation.19,20 Oblique and other views can be added to avoid superimposition of the object over bony structures. Radiopaque foreign bodies may be invisible if they are projected over or impacted within bone.21 Metal, bone, teeth, pencil graphite, certain plastics, gravel, sand, and aluminum are all visible on plain radiographs.3,20,22 Glass fragments have been thought to require lead or heavy metal content to be visible. However, glass fragments as small as 0.5 mm appear on two-view plain radiographs if not obscured by bone fragments; and glass fragments as small as 2 mm appear in the presence of overlying bone regardless of lead content.23,24 Organic materials and plastics are not reliably detected on plain radiographs. They may be indirectly shown as a radiolucent filling defect when the object is less dense than the surrounding tissue, making plain radiography worthwhile even in cases of suspected nonradiopaque foreign bodies.25,26 It is important to examine the entire radiograph for the appearance and location of an unexpected foreign body.27 The evaluation can be terminated after adequate wound exploration and plain radiographs for a known radiopaque foreign body, if nothing is found. Other imaging modalities are required if there is a strong suspicion for a retained foreign body of the type that is not usually demonstrated on plain radiographs. The advantages of plain radiographs include their universal availability, low cost, and familiarity to most Emergency Physicians. The disadvantages include the inability to resolve objects with densities similar to body tissues. Plain films do not demonstrate anatomic structures that may be intervening between the skin and foreign body along the planned surgical approach. It may be difficult to accurately judge the depth of a foreign body using twodimensional radiographs.8 Despite these drawbacks, standard radiographs remain the most clinically practical means of screening for foreign bodies.19
ULTRASOUND Radiography alone is not sufficient to detect nonradiopaque foreign bodies. Bedside ultrasound has become available in many Emergency Departments. The lack of radiation exposure or harm to patients and its ease of use dictates an assessment with bedside ultrasound by the Emergency Physician as a screening tool when foreign bodies are suspected or not found on plain radiography.28 Many recent studies have shown ultrasonography to have a higher sensitivity for nonradiopaque foreign bodies than plain radiography.28,29 High-resolution real-time ultrasound using a 7.5 MHz or greater linear array probe or transducer, in the hands of a skilled and experienced operator, can detect radiolucent superficial foreign bodies with a similar radiographic density as the surrounding tissue.8,30–34 This can include wood, small glass fragments, fish bones, sea urchin spines, and other vegetative material.8,34–38 Wood foreign bodies can act as a source for infection and should be evaluated with ultrasound in patients where radiographs are negative.35 This is especially important in the Emergency Department where wood foreign bodies make up as much as 34% of all foreign bodies and plain radiographs have a sensitivity as low as 7.4% for organic material.36 Patient perception of a retained foreign body and the use of bedside ultrasound can localize a retained object with a sensitivity of 88.9% and a specificity of 76.5%.37 One study showed that the accuracy of detection was above 80% for radiolucent objects by ultrasound technologists, Radiologists, and Emergency Physicians.38 Ultrasound has the ability to localize a foreign body within three dimensions, thus helping to establish its relation to adjacent bone, muscle, tendons, and tendon sheaths.32 Preoperative ultrasound results in less damage to the surrounding tissues, reduced operative time, and reduced postoperative morbidity.32,39
FIGURE 97-1. A sonographic image of a subcutaneous thorn. The foreign body is hyperechoic (white) with an acoustic shadow deep to it.
The procedure for locating a subcutaneous foreign body with ultrasound begins with selecting the highest available transducer frequency.40 Higher frequency transducers have better resolution for superficial structures. The use of a standoff pad or gel filled glove (with the air and talc carefully removed) can act as a dead zone for objects that would normally be too superficial to fall within the focal zone of the transducer.41,42 Adjust the focus to the required depth and proceed to scan the field in two orthogonal planes.40 The scanning beam must be oriented parallel to the long axis of a hemostat, which can be directed toward the long axis of the foreign body.31 Please refer to Chapter 98, Ultrasound-Guided Foreign Body Identification and Removal, for more complete details. The sonographic appearance of foreign bodies is related to the surface characteristics and not its composition.43,44 Metals and needles are often hyperechoic with reverberation artifact or comet tails. Gravel is usually hyperechoic and shows dense posterior acoustic shadowing. Organic materials such as wood have a characteristic appearance and are ideal for ultrasonographic evaluation. Wood is most often hyperechoic with a posterior acoustic shadow (Figure 97-1). Furthermore, the foreign body is often surrounded by a hypoechoic halo37,42,44 (Figure 97-2). This is
FIGURE 97-2. A sonographic image of several shards of glass in the palm. Note the hyperechoic (white) foreign bodies surrounded by an echo-poor (black) signal consistent with either a hematoma or edema.
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frequently a zone of edema, granulation tissue, or abscess.40 While this hypoechoic halo can represent an inflammatory response, it may not be visible within 24 hours of the wound.35 Doppler ultrasound shows a hypoechoic (black) ring around a hyperechoic (white) foreign body. Doppler also shows marked hyperemia around the periphery of a foreign body, something considered to be a reliable secondary sign.45 Once a foreign body has been located on ultrasound, both ends of the object should be marked.46 This is often done by inserting paperclips between the skin and the transducer and connecting both ends with a marked dotted line. Meticulously scan along the entire length of the suspected object and also visualize the foreign body perpendicular to the transducer. There are several disadvantages when using ultrasound, including the level of skill required for its use in diagnosing musculoskeletal foreign bodies.46–49 Studies assessing the accuracy of ultrasound have shown a sensitivity of 30% to 100% and a specificity of 70% to 90%.49 These values have been mostly demonstrated in referred patients studied by Radiologists and certified technicians.50,51 Ultrasound by Emergency Physicians has a specificity of only 59% under conditions that replicate a typical Emergency Department situation.51 Another disadvantage is that false positives can occur with tendons, old scar tissue, calcifications, fresh bleeding, sutures, air in wounds, sesamoid bones, ossified cartilage, or keratin plugs.8,35,42 Ultrasound localization may also be difficult if the object is close to bone or deep to subcutaneous gas.43 As such, Emergency Physicians with a high suspicion for a retained subcutaneous foreign body not identified by bedside ultrasound should request a formal diagnostic imaging study.
COMPUTED TOMOGRAPHY (CT) SCAN CT imaging should be requested in cases where radiography and ultrasonography have failed to demonstrate suspected foreign bodies such as nonradiopaque material or those that cannot technically be located by ultrasound due things like overlying bone or gas.52 CT is valuable because it is more sensitive in differentiating densities and thus is capable of detecting more types of foreign bodies.14,53–56 The modality can also be used in high-risk wounds when there is potential for infection or joint involvement. CT images can be created in multiple planes and can demonstrate the relationship of a foreign body to important anatomic structures.53,57 CT-guided percutaneous placement of a catheter or needle can guide surgical dissection to a foreign body, aiding in the subsequent removal.53,57 The disadvantages of CT scanning include its higher cost, radiation dosage, the need for patient cooperation, and availability. Additionally, organic foreign bodies become less visible over time due to absorption of body fluids.28
MRI MRI appears to be more accurate than any other modality for identifying wood, glass, plastic, spines, and thorns.14,53 It is superior to CT scanning in detecting the presence and extent of edema, hemorrhage, and infection surrounding foreign bodies.14,53 Wood foreign bodies often show linear hypointensity with an associated surrounding inflammatory response.28 MRI’s other advantages include the high resolution and contrast between adjacent tissues. It allows the precise localization of foreign bodies in three dimensions to aid in surgical planning and assessment of the need for advanced exploration, debridement, and irrigation. It does not expose the patient to any radiation.58 The disadvantages of MRI include its lack of availability and high cost. Patients must be assessed to rule out a magnetic foreign body due to the risk of movement of the foreign body during MRI scanning.59 Prior history of an ocular or other metallic
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foreign bodies must also be sought prior to MRI scanning to prevent iatrogenic injury. This requires a thorough screening history and plain radiographs prior to MRI scanning. Gravel and ferromagnetic substances produce significant artifact.14 Differentiating scar tissue, tendons, and calcifications from an actual foreign body can be challenging.60 MRI is better suited to evaluate the complications of foreign bodies and is not used routinely in the Emergency Department.
INDICATIONS Every effort should be made to identify foreign bodies, even if they are not likely to be removed. It must be decided whether a foreign body needs to be removed immediately, electively, or at all once identified. Factors that influence the decision to proceed with attempted removal include the size and reactivity of the foreign body, its proximity to vital structures, and associated injuries. These must be weighed against the potential for further tissue damage and contaminating the wound. A foreign body requires immediate removal if it is likely to provoke significant tissue inflammation or injury.3,61,62 Contaminated objects such as teeth, soil, or foreign bodies located in the presence of an established infection should be immediately removed.3,11 Allergenic foreign bodies, toxic foreign bodies, or those causing hemorrhage or ischemia should be immediately removed.3,62 Foreign bodies interfering with sensory or motor function, or having the potential for migration, should be urgently removed.3 Foreign bodies in the hands and feet usually require removal as they may cause persistent pain and can sever nerves or tendons much later.5 The foreign body may require removal for cosmetic or psychological reasons in some cases.1
CONTRAINDICATIONS The foreign body should be urgently removed under ideal conditions by an appropriate Surgeon when it is associated with a neurovascular injury or is located near tendons, nerves, or blood vessels.1,3 Deep exploration of the hands or feet should be avoided to prevent injuring the intricate structures. Large, deep, and impaled foreign bodies are assumed to be tamponading hemorrhage, should initially be left in place, and urgently removed in the Operating Room.27 Foreign bodies associated with fractures or located within a joint require prompt surgical debridement to prevent osteomyelitis or septic arthritis.62 Urgent surgical intervention is required for all high-pressure injection injuries. These injuries may initially appear innocuous but often cause extensive damage and carry a significantly high risk of complications.62 Consider referral based on one’s own experience, anticipated problems related to the foreign body’s location or depth of penetration, the duration of retention, or other patient factors likely to complicate the procedure or follow-up. A deeply embedded, inert object not near any vital structures can be left in place. The difficulty of removal is usually not worth the potential tissue damage. These patients can be referred for elective removal, if necessary.1,62 If the decision is made not to remove a foreign body, the patient must be informed and the issues discussed including the potential for migration and infection. Document this discussion in the medical record.
EQUIPMENT • • • •
18 gauge needles 27 gauge needles 10 mL syringes Povidone iodine or chlorhexidine solution
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• • • • • • • • • • • • • • • • • • • • • • • • •
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Lidocaine (1%) with and without epinephrine Topical 4% liposomal lidocaine Depilatory wax, rubber cement, or hardening facial gel #11 scalpel blade on a handle #15 scalpel blade on a handle Nylon suture, 1-0 or 2-0 Methylene blue Paper clips Wire grid Eye magnet Hemoclips Hemoclip applier Fluoroscopy unit Hemostats, two sizes Forceps 22 gauge needles for foreign-body localization Magnification eye loupes Normal saline 19 gauge blunt-tip needle or angiocatheter 35 mL syringe Blood pressure cuff or Penrose drains 4 × 4 gauze squares Adhesive tape Bedside ultrasound with high frequency transducer Standoff pad or gel filled glove
PATIENT PREPARATION Foreign body removal can be frustrating and time consuming, even when performed under ideal conditions. It is appropriate to set a time limit that is reasonable based upon the staffing and volume of the Emergency Department. Approximately 10 to 30 minutes is appropriate to find and remove an embedded foreign body. Inform the patient of the planned time limit at the outset. The search should be discontinued and the patient referred to a Surgeon after expiration of the predetermined time. Apply povidone iodine or chlorhexidine to the skin site surrounding the wound. Avoid spilling the solution into the wound cavity as both are toxic to wound defenses and may increase the incidence of a subsequent wound infection.12 Obtain a bloodless field for the examination. Place a blood pressure cuff proximal to the injury. Elevate the extremity for at least 1 minute and then inflate the cuff to a pressure greater than the patient’s systolic blood pressure. Although it will cause some discomfort, this is safe for up to 2 hours.63 A local vasoconstrictor can be used
FIGURE 97-3. Creating an ellipse to remove a contaminated or embedded foreign body. A. An ellipse is made in the skin surrounding the foreign body. B. The epidermis is removed to expose the foreign body. A block of subcutaneous tissue (dotted line) can be removed if the foreign body is difficult to visualize. C. The skin, the subcutaneous tissue, and the foreign body can be removed en bloc.
with the anesthetic to control localized capillary bleeding if no contraindications exist. A 0.25 to 0.50 in. Penrose drain can be wrapped tightly around a finger or toe and secured in place with a hemostat. Adequate anesthesia is crucial to the procedure. A field block or regional nerve block, depending upon the location of the foreign body, best accomplishes anesthesia without distorting the wound further by local infiltration.64 Consider using topical anesthetics in the pediatric population. Liposomal lidocaine (4%), for example, has a very fast onset and is associated with higher success rates, reduced procedure time, and less pain.65,66 The techniques of topical and regional anesthesia are described in Chapters 124 through 127. Procedural sedation (Chapter 129) or general anesthesia may be required, especially in children where cooperation may not be otherwise possible.
TECHNIQUES SUPERFICIAL WOOD OR ORGANIC SPLINTER REMOVAL Very fine foreign bodies can be difficult to visualize. One method to help localize them is to spread soft soap very lightly over the skin.67 Only superficial organic splinters and foreign bodies should be pulled out with forceps as they often come apart leaving a fragment that is more difficult to remove.3,68 Occasionally, cactus spines or wood splinters lie superficial and parallel to the skin surface. Make an incision parallel to the long axis of the foreign body and then lift it out of the wound. Enlarge the skin entrance wound with a scalpel so that the foreign body can be grasped and withdrawn with a hemostat under direct visualization if it is lodged in the subcutaneous tissue. Small cactus spines may be difficult to locate and remove directly. Application of a depilatory wax, rubber cement, or a water-soluble facial gel with a brush can successfully aid in the removal of small fine spines.61 Apply the wax, rubber cement, or facial gel over the skin containing the protruding spines. Apply a layer of gauze over the wet substance. Allow the substance to dry onto the skin and the gauze. Remove the gauze to lift off the dried substance and attached spines. Repeat this process as required to remove the remaining spines.
PUNCTURE WOUNDS Puncture wounds of the foot are commonly seen in Emergency Departments. Punctures frequently, drive pieces of clothing, shoes, or other debris deep into the wound resulting in an infection rate of approximately 10%.69,70 Although technically difficult, puncture wounds in the distal foot may profit from debridement and irrigation. Puncture wounds can be trimmed or ellipsed to remove contaminated and/or embedded foreign bodies (Figure 97-3).3 This
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FIGURE 97-4. Removal of a foreign body embedded perpendicular to the skin. A. The embedded foreign body. The dotted line represents the proposed incision line. B. A linear incision is made 1 mm lateral to the foreign body. C. The incision is spread open to visualize and remove the foreign body.
technique also works well for foreign bodies that are difficult to localize. Make an ellipse in the skin surrounding the foreign body with a #15 scalpel blade (Figure 97-3A). Lift up the ellipse of skin and separate it from the underlying dermis (Figure 97-3B). The foreign body may be visible. Grasp it with a hemostat or forceps and remove it from the tissue. If unable to exactly localize the object, the foreign body and the ellipsed puncture wound can both be extracted in a block of tissue (Figure 97-3B, dotted line).64 First ensure that no nerves, blood vessels, or tendons will be injured. Alternatively, make the skin ellipse and extract the block of tissue containing the foreign body without dissecting the skin from the subcutaneous tissue (Figure 97-3C). Both techniques allow for the removal of foreign bodies and better cleaning of the wound. Puncture wounds of the foot require careful follow-up due to the risk of infection. There are several alternative techniques if removing an ellipse of skin and/or tissue is contraindicated or if the Emergency Physician is not comfortable with this technique (Figures 97-4 & 97-5). A foreign body may be embedded perpendicular to the skin (Figure 97-4A). Make a linear incision that passes 1 mm to the side of the puncture wound with a #15 scalpel blade (Figures 97-4A & B). Spread the incision open. Visualize the foreign body, grasp it with a hemostat, and remove it. The final technique of removing a foreign body from a puncture wound involves making a superficial skin incision and manually expressing the foreign body (Figure 97-5). Make an elliptical incision surrounding the foreign body or a linear incision over the foreign body (Figure 97-5A). Remove the ellipse of skin or spread the linear incision. Undermine the subcutaneous tissues surrounding
FIGURE 97-5. An alternative technique to remove a foreign body from a puncture wound. A. Incise and remove an ellipse of epidermis (1). Alternatively, make a linear incision centered over the foreign body (2). B. Undermine the subcutaneous tissue surrounding the foreign body. Apply digital pressure (arrows) to visualize and express the foreign body.
the foreign body (Figure 97-5B). Apply digital pressure over the undermined areas to displace the foreign body into the center of the wound and upward (Figure 97-5B). Grasp the foreign body with a hemostat and remove it.
NYLON SUTURE LOCALIZATION One technique described for use in fresh wounds involves the localization of a foreign body by marking its entry tract with a nylon suture.71 Grasp a piece of 1-0 or 2-0 nylon suture between the thumb and index finger. Rotate the suture while pushing it into the wound so that it follows the tract made by the foreign body. It is reported that the foreign body is easily felt when the nylon contacts the foreign body.71 Leave the suture in the wound tract. Open the wound tract by cutting alongside the nylon suture until the foreign body is reached, at which time it is removed. A 92% success rate up to 48 hours after the time of injury has been reported with this technique.71
GEOMETRIC APPROACH FOR A NEEDLE IN THE FOOT A technique that is useful for the removal of a needle in the plantar surface of the foot involves the use of standard anterior, posterior, and lateral radiographs to identify the cutaneous site corresponding to the location of the needle.72 The incision site is determined by bisecting the midpoint of the needle, as seen in each projection, by a line drawn at right angles to the long axis of the needle. The ideal plane of dissection is perpendicular to the needle’s midpoint, which is correlated with the surface anatomy of the foot. Prepare and anesthetize the skin after determining the dissection plane. Make a 0.5 to 1.0 cm skin incision in the plane perpendicular to the needle in its midpoint. Advance an iris scissors into the incision and along the dissection plane with the blades slightly open. Advance the scissors 1 to 2 mm and close the blades. Withdraw the scissors slightly. Open the blades of the scissors, advance them 1 to 2 mm, and close the blades. Care must be taken to avoid cutting the flexor tendons, although they are located deep and in close association to the bones of the foot. Continue this process of advancing and closing the blades until the needle prevents closure of the scissors. Advance a hemostat into the wound and over the blades of the scissors. Grasp and secure the needle. Pull the hemostat out of the wound to simply back the needle out of its entry tract. This procedure is reported to have a 100% success rate and takes approximately 10 minutes.72
DYE LOCALIZATION Methylene blue may be used to track the location of a foreign body.73 Identify the presence of a needle or foreign body on plain radiographs. Clean and prepare the skin. Sterilely inject 0.1 to 0.2 mL
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of methylene blue very gently through the entrance wound of the foreign body. The dye will travel along the path of least resistance, that is, the path of the foreign body. Make an A-, U-, V-, or Y-shaped incision from the point of entry and raise a flap of tissue. The blue dot of dye serves as a guide to the location of the foreign body. This procedure is often complicated by seepage of dye and is therefore of limited value.
PAPER CLIP X-RAY LOCALIZATION Simple paper clips may be used to locate a foreign body.74,75 Obtain plain radiographs to demonstrate the presence of a radiopaque foreign body. Bend two or more paperclips into different shapes. Place the ends over the wound entry site. Secure the paper clips in position with tape. Obtain two plain radiographs taken at right angles to each other. Examine the radiographs to determine the cutaneous location of the foreign body in relation to the paper clips and note its depth from the skin surface. Mark the exact cutaneous location of the foreign body on the patient’s skin with a permanent ink pen. Remove the paper clips. Clean, prepare, and anesthetize the skin. Make a stab incision at a 90° angle to the middle of the foreign body, taking the shortest distance between the skin and the foreign body, and following the method discussed for the geometric approach for a needle in the foot. Insert a small hemostat into the incision. Advance the hemostat allowing localization of the object with minimal probing. Grasp and remove the foreign body.
WIRE GRID LOCALIZATION This technique follows a similar approach to the paper clip method.76 Place a wire grid over the skin. Obtain radiographs in two planes to locate the object within the grid system. Mark the skin and remove the grid. Remove the foreign body as discussed for the paper clip technique.
NEEDLE GRID LOCALIZATION The grid principle may also be used to remove superficial and nonlinear radiopaque foreign bodies after they have been identified on plain radiographs. Clean, prep, and anesthetize the skin. Insert three 25 gauge, 1.5 in. needles into the skin near the estimated location of the foreign body and at right angles to each other. Obtain two orthogonal plain radiographs. This process can be repeated, each time moving the needles slightly until one is superimposed on the foreign body. Determine the cutaneous position of the foreign body by noting its position within the needle grid. Mark this position on the skin. It must be remembered that this technique does not provide a true three-dimensional image since divergence and parallax distortion of images occur on the radiographs.3 The Emergency Physician must recall that tendons and other structures may block the planned path to the object.7 Make a 0.5 to 1.0 cm incision in a plane perpendicular to the long axis of the foreign body to an appropriate depth or dissect along the path of the closest needle.27 Identify and remove the foreign body. A drawback of this technique is the potential for dislodging of the needles with attendant repeated trips to the Radiology Department. The use of a portable fluoroscopy unit will prevent this problem. Another similar technique involves the placement of three to four needles of different gauges at 90° to each other in the anesthetized subject.77 Obtain repeat radiographs to identify which needle is closest to the object. Remove all but the closest needle. Make an incision down to the estimated depth where the foreign body is located. Identify and remove the foreign body.
EYE MAGNET Another technique reported to have a good success rate in removing metallic foreign bodies utilizes a hand-held eye magnet.78 Confirm the presence of a radiopaque foreign body with plain radiographs. Prepare, drape, and anesthetize the area. Slightly enlarge the entry wound to permit entrance of the magnet tip. Apply a sterile ultrasound probe cover or glove over the magnet. Gently probe the wound track with the magnet until a “click” is appreciated. Withdraw the magnet with the foreign body attached to the magnet. Perform further and more directed wound exploration with the magnet if resistance is met. This technique is likely of limited value.
TAGGED HEMOCLIPS It can be difficult to find foreign bodies once the dissection actually begins since the tissues may be distorted by retraction, edema, or local anesthesia; even with the most elaborate marking system using grids or needles. The tagged Hemoclip method was developed to address this problem.79 It requires a skin incision and dissection down to where the physician believes the foreign body to be, based as observed on plain radiographs. Prepare two or three Hemoclips with a long silk suture attached to each one. Place them into the Hemoclip applier. Dissect down to where the foreign body is believed to be located. Place two or three Hemoclips into the depths of the wound. Obtain repeat radiographs to show the relationship of the foreign body to the Hemoclips. Remove all but the closest Hemoclip. Dissect towards the Hemoclip and the foreign body. Identify and remove the foreign body. Remove the Hemoclip. If the foreign body is not readily found, repeat the procedure after placing two or three additional Hemoclips. Follow the trail of Hemoclips to the foreign body.
ULTRASONOGRAPHIC REMOVAL There are a multitude of different approaches to the ultrasoundguided removal of subcutaneous foreign bodies.37,40–42,46,80 A detailed working knowledge of the pertinent anatomy is essential. Locate and mark the location of the foreign body. Clean, prep, and anesthetize the skin. Insert a needle under ultrasonographic guidance. The ultrasound monitor screen will display a hyperechoic linear object with posterior reverberation effect. Guide the needle under ultrasound until it touches the foreign body. Make a skin incision down to the foreign body. The addition of a second needle in a perpendicular plane can enhance the objects localization.41 Inset a closed hemostat to approach the foreign body.41,80 Ideally, the hemostat should be inserted along the plane of the foreign body. Open the jaws of the hemostat under sonographic guidance to reveal two echogenic structures, the jaws of the hemostat, with posterior reverberation effect. Once the object is within the hemostat’s grasp, it can be removed under sonographic guidance. Always rescan the area after the foreign body is removed in order to ensure that no additional fragments remain. Patients should be instructed to return if there are any signs of infection.46 A more detailed description of ultrasound-guided foreign body removal is available in Chapter 98.
FLUOROSCOPIC TECHNIQUES Fluoroscopy offers an excellent aid in the removal of radiopaque foreign bodies.81 Make an incision over the foreign body as judged from plain radiographs. Localize the foreign body under fluoroscopy. Guide a curved hemostat to the foreign body with brief intermittent exposures of the fluoroscopy unit.82 Grasp and remove the foreign body. This procedure exposes the operator’s hands to radiation and may risk damaging structures in the wound by blind manipulation of the hemostat.83
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The grid and needle localization techniques described previously can be applied under fluoroscopy. Rotate the site of injury under the fluoroscope to visualize the foreign body between the markers. This may improve the ability to judge the location of the foreign body in three dimensions and aid in its removal. Intermittent exposure with a fluoroscope can allow repositioning of the needles until the foreign body is localized between two needles or at the tip of a single needle. Make a small incision carried down to the foreign body and remove it.83,84 Additional techniques using fluoroscopy and neurosurgical stereotactic devices have been described.3 The cost, availability, and practicality make these approaches unattractive in the Emergency Department and are therefore not discussed further.
AFTERCARE It is often prudent to take postextraction radiographs to ensure complete removal of the foreign body, especially if multiple objects are involved or if there is concern about the object fragmenting.77 Carefully irrigate and debride the wound of all epidermal fragments.3 The most effective form of wound preparation and cleansing is jet lavage irrigation with normal saline to decrease the bacterial load in the wound and the risk of developing infection.85 This can be performed with a commercially available device or a 35 mL syringe armed with a 19 gauge angiocatheter or blunt needle.12 Studies of simple pediatric wounds has found that using drinkable tap water to irrigate wounds is a good alternative to saline, as it shows similarly low infection rates.86 The quality of mechanical cleaning is important to wound prognosis.1 Clean, thoroughly irrigated, and debrided wounds with a good blood supply do not require antibiotics and may be sutured closed after removal of the foreign body. Patients should be followed up in 5 to 7 days for suture removal. If complete cleansing of the wound is not assured or if the wound is at significant risk for infection for other reasons, delayed primary closure or healing by secondary intention should be considered.12,87 Delayed primary closure involves packing the wound open for 4 to 5 days, after which it is reassessed and closed primarily if the edema has resolved, no infection is present, and exudate has been removed. This technique results in minimal tissue damage. It is especially useful in clean contaminated and contaminated wounds, achieving a 90% success rate in appropriate patients. Antibiotic therapy may be considered in those with wounds that are at significant risk for infection. But, antibiotics are not a replacement for proper wound care. Infection rates for traumatic wounds range from 4.5% to 6.3%. Those patients who are immunocompromised, have puncture wounds, crush injuries, open fractures, bites, burns, frostbite, or wounds that involve tendons and cartilage as well as those wounds contaminated with feces, soil, saliva should be considered high risk and should be considered for antibiotic therapy.88,89 Close follow-up is especially important in these patients. Prophylaxis for endocarditis is not recommended unless foreign body removal is undertaken through an area of an established infection.90 Splint the involved extremity if the foreign body is near a joint, a highly mobile region, or a vital structure to prevent injury and/or migration of the foreign body if the patient is referred for delayed removal.8 A more complete discussion on wound cleansing, wound irrigation, and the general principles of wound management can be found in Chapter 92.
TETANUS PROPHYLAXIS Tetanus prophylaxis must be considered for wounds involving foreign bodies. Wounds contaminated with feces, soil, or saliva,
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puncture wounds, avulsions, and wounds resulting from missiles, crushing, burns, and frostbite are considered to be tetanus prone. Recent studies have found that up to 26% of those patients reporting they were up to date with tetanus vaccination were confirmed not to be, while a further 30.2% were indeterminate.91 In the Emergency Department, it is vital to investigate a patient’s tetanus status and vaccinate according to the accepted guidelines.40,92 For patients who have had three or more doses, those who received their previous dose within 5 to 10 years presenting with a nonclean and minor wound should receive the Tdap booster (preferred over the Td booster). Those patients who have gone more than 10 years since their last dose should also receive the booster regardless of wound type. All patients who have fewer than three doses or an uncertain vaccination history should receive the vaccine booster. Of these patients, those with complicated or contaminated wounds (such as those due to a puncture) should receive the tetanus immunoglobulin (TIG) in addition to the vaccine booster.92 Please refer to Chapter 92 for more complete details regarding tetanus prophylaxis.
COMPLICATIONS The removal of embedded foreign bodies is relatively free of complications if properly conceived. Care must be taken to document the functional and neurovascular status prior to and after any significant manipulations. Appropriate referral of complicated cases, including those with foreign bodies located deep in the hands, the feet, or near vital structures will lessen the risk of unfavorable outcomes. Infection remains the most common complication of a retained foreign body, even when the object itself is not contaminated. Aseptic technique and avoidance of excessively prolonged manipulation and searching for embedded foreign bodies are important to prevent introducing infection into a previously sterile area. In cases where the foreign body cannot be found, it may be necessary, although less than ideal, to wait for abscess formation in order to pinpoint the location of an object at a later time.3 Referral for additional imaging and removal may be appropriate. The patient must be advised in detail of the likely course, and follow-up must be assured and documented.
SUMMARY Virtually all embedded subcutaneous foreign bodies should be identified and located with rigorous assessment of each and every traumatic wound and a high index of suspicion. The history and physical examination should guide the search for retained foreign bodies and the approach to locating them. The majority of foreign bodies are visible on plain radiographs. Wounds for which a radiopaque foreign body may be retained should be imaged with standard radiographs utilizing a soft tissue technique. Bedside ultrasound should be utilized to assist in the identification and removal of subcutaneous foreign bodies. Additional diagnostic imaging with CT, ultrasound, or MRI may be indicated if the suspected foreign body is likely to be radiolucent or is not adequately identified. Once identified and located, several techniques are available to aid in localization and removal. A decision must be made regarding the necessity of immediate or urgent removal in the Emergency Department or by referral to a specialist. Inert foreign bodies that are unlikely to cause long-term complications may be left in situ with information provided to the patient explaining the reasoning behind this conservative approach. Appropriate wound care is crucial to satisfactory healing, and postprocedure follow-up must be assured.
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Ultrasound-Guided Foreign Body Identification and Removal Daniel S. Morrison
INTRODUCTION Retained foreign bodies are associated with up to 1.9% of all wounds.1 The presence of a foreign body in a wound increases the incidence of a wound infection.2 Retained foreign bodies are also a major cause of litigation against Emergency Physicians.3,4 A high index of suspicion for a retained foreign body must be maintained whenever there is the potential for a foreign body in a wound.5,6 This chapter focuses on ultrasound-guided identification and removal of subcutaneous foreign bodies. Foreign bodies may be small, leave no skin entry marks, and consist of many different types of material. Almost any object (solid, liquid, or gas) can become a foreign body and present itself in a location where it should not reside. Standard radiographs and fluoroscopy are good at identifying radiopaque objects such as metal, gravel, and glass.7–13 The ability of these techniques to identify a foreign body varies by the size and composition of the foreign body.9 MRI and CT are useful to detect foreign bodies.12,14,15 These are expensive imaging modalities and the images vary depending upon the length of time the foreign body has been present.15 Certain foreign bodies may produce artifacts that diminish the MRI and CT image qualities.12 Plastic, hair, vegetative material, and rubber are not radiopaque and are not routinely identified on radiographs.6–8,10–13,16–18 Ultrasound (US) is able to identify radiopaque foreign bodies. US can also detect foreign bodies that are not radiopaque due to their different echotextures in relation to surrounding structures.6,8,14–30
ANATOMY AND PATHOPHYSIOLOGY Foreign bodies can be present in almost any part of the body. Foreign bodies can be detected with US even when they are found in nontraditional places. They have been identified in the eye,31 esophagus,29 and tongue32 with US. Foreign bodies isolated to small spaces, such as in the web spaces of the hand, may not be identified due to the size of the US probe footprint and the difficult anatomic location to scan.26 Not diagnosing foreign bodies can be dangerous for the patient and lead to an increased risk of complications. Legislation to introduce an aluminum penny into circulation in the United States in 1973 was defeated in part by Pediatricians and Pediatric Radiologists concern that these new coins would not be easily identified on radiographs.33 Patients with retained lead foreign bodies can have statistically significant elevated blood lead levels as compared with matched controls.34 Foreign bodies have specific US characteristics. Smooth and flat surfaces typically produce a dirty shadowing or reverberation artifact.35,36 Irregular surfaces with a small radius or curvature produce a more clean shadow (Figure 98-1). Glass and metal typically produce a ring-down or reverberation artifact11,23,28,29,35,37 (Figure 98-2). A wood foreign body produces a bright echogenic reflection with a strong acoustic shadow6,11,29,38 (Figure 98-3). Foreign bodies residing in soft tissue longer than 24 hours can cause an inflammatory reaction, which creates a hypoechoic rim around the echogenic foreign body (Figure 98-4).35
FIGURE 98-1. US image of a subcutaneous pebble. Notice the hyperechoic short radius and tight curvature. The pebble casts a strong acoustic shadow as it blocks transmission of the US beam.
INDICATIONS Patients with a foreign body sensation or soft tissue mass should be considered to have a foreign body until ruled out.5,16 Foreign bodies can migrate great distances from the original insertion site requiring the Emergency Physician to maintain a high index of suspicion for a foreign body.39 Any patient in which the Emergency Physician has any index of suspicion for a foreign body should have additional investigations. Wood, thorns, spines, vegetative foreign bodies, dirt, clothing, and heavily contaminated foreign bodies should be removed immediately, as should those with potential for migration or entrance into the systemic circulation. It is generally believed that glass, metal, and plastic are inert and can be removed electively as they tend to be encysted by scar tissue. Their removal is dependent on the specific situation, physician preference, and patient characteristics. Patients who have
Hyperechoic upper surface
Reverberation artifact
FIGURE 98-2. US image of a subcutaneous metallic BB. The BB is hyperechoic and produces a reverberation artifact.
CHAPTER 98: Ultrasound-Guided Foreign Body Identification and Removal
A
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B
FIGURE 98-3. US image of a subcutaneous wood foreign body. The wood produces a strong hyperechoic reflection and a hypoechoic acoustic shadow. A. Long axis US view. B. Short axis US view.
persistent pain, neuropraxia, impairment of function, limitation of range of motion of a joint, or psychological distress should have the foreign body removed. Foreign bodies adjacent to bone can cause osteomyelitis and should be removed within 96 hours.40 Any patient in whom a foreign body, especially wood, was removed should have a further investigation to ensure there are no additional foreign bodies or a fragment of the removed foreign body present.18
CONTRAINDICATIONS US is a safe imaging modality without any known ionizing radiation. There are no known contraindications to using US to identify and remove a foreign body.
EQUIPMENT • • • • • • • • • • • • • •
US machine High frequency linear US probe Sterile US probe cover or glove Skin cleansing solution (chlorhexidine or povidone iodine) Sterile US gel (or other type of sterile gel, i.e., Surgilube) #11 scalpel blade Suture kit or individual components (sterile drape, gauze pads, hemostat, and forceps) Local anesthetic solution, usually lidocaine 5 mL syringes 27 gauge needles 18 gauge needle to draw up local anesthetic solution Skin marking pen Paperclips Stand-off pad (or a 50 mL or 100 mL saline bag)
PATIENT PREPARATION
FIGURE 98-4. US image of a subcutaneous wood foreign body that has been in place for over 24 hours. The inflammatory reaction forms an anechoic rim around the foreign body (Courtesy of James W. Tsung, MD, MPH).
Obtain informed consent in which the risks, benefits, and any alternative treatment modalities are discussed. Cleanse the skin of any dirt and debris. Apply a liberal amount of US gel over the area in which the foreign body is suspected. Use a high frequency linear US probe to search for the foreign body. Look for signs of the foreign body such as reverberation artifact, comet-tail artifact, acoustic shadowing, a hypoechoic rim surrounding an echogenic structure, or any other signs associated with foreign bodies. Foreign bodies may be very superficial. It may be necessary to change the focal zone on the US machine. An acoustic interface may assist in locating a superficial foreign body. Apply a stand-off pad over the site of the foreign body. This can be either a commercially available stand-off pad, a small saline bag in which the air is removed, or a glove filled with saline or US gel.17,41 The water bath technique works well for the hands and feet. Place the body part
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A
B
FIGURE 98-5. Paper clip localization of a foreign body. The wood foreign body has a bright echogenic reflection and casts an acoustic shadow. The paper clip casts a ringdown or reverberation artifact that is lined up over the leading edge or most superficial aspect of the foreign body. A. Long axis US view. B. Short axis US view.
in a water-filled container. Place the US probe in the water-filled container without actually contacting the patient’s skin. Identify the presence of a foreign body. Once identified, it must be localized to make removal easier for the patient and the Emergency Physician.
TECHNIQUE PAPER CLIP LOCALIZATION AND REMOVAL Since the foreign body is located under the skin, its location should be marked on the patient’s skin. It is helpful to use a metal foreign body, such as a paper clip, to create a shadow to locate the foreign body. The metal paper clip will cast a distinct shadow. Identify the foreign body on US. Place the US probe on the patient’s skin above the foreign body. Turn the US probe so its long axis is aligned with the long axis of the foreign body. Insert the tip of an unfolded paper clip between the US probe and the skin surface. Slowly advance the paper clip until the shadow it casts aligns with the leading edge (the most superficial aspect) of the foreign body (Figure 98-5). Use a skin marker to mark this location on the patient’s skin. Rotate the US probe 90° to visualize the short axis or cross-sectional view of the foreign body. Insert the tip of the unfolded paper clip between the US probe and the patient’s skin. Mark the location on the patient’s skin where the shadow cast by the paper clip aligns with the leading edge of the foreign body. The intersection of these two lines is where the leading edge of the foreign body resides under the skin. Prepare to remove the foreign body. Prepare a 5 mL syringe with a 27 gauge needle and local anesthetic solution. Cleanse the patient’s skin with chlorhexidine or povidone iodine solution and allow it to dry. Apply sterile drapes to form a sterile field. Inject local anesthetic solution subcutaneously around the skin markings over the leading edge of the foreign body. Prepare the US probe. Apply US gel to the footprint of the US probe. Apply a sterile probe cover or a sterile glove over the US probe. Squeeze any air out of the space between the US probe and the cover. Apply sterile US gel on the probe cover. The Emergency Physician should don sterile gloves. The use of a hat, face mask, and sterile gown is not necessary for this procedure. Grasp the US probe with the nondominant hand. Align the long axis of the US probe along the long axis of the foreign body, and
approximately 3 to 4 mm proximal to the skin markings. Aim the syringe containing the local anesthetic solution downward and in the direction of the foreign body. Slowly insert and advance the needle through the skin mark under US guidance while slowly injecting a small volume of local anesthetic solution. The injection of local anesthetic solution around the foreign body creates a hypoechoic halo that helps with the identification of the foreign body. Stop advancing the needle when the tip reaches the foreign body. Remove the needle without moving the US probe. Use a #11 scalpel blade to make a small skin incision just proximal to the skin mark and in an area that has been previously anesthetized. Insert the jaws of a closed hemostat or the arms of a closed alligator forceps into the skin incision. Advance the instrument under US guidance and bluntly dissect down to the foreign body. Align the tip of the instrument with the leading edge of the foreign body (Figure 98-6). Open the instrument, grasp the foreign body, and remove it.
FIGURE 98-6. Retrieval of the foreign body. US image of the forceps approaching a wood foreign body. Note that the arms of the forceps are open and in line with the foreign body.
CHAPTER 99: Tick Removal
NEEDLE LOCALIZATION AND REMOVAL Identify the foreign body using US. Cleanse the skin, apply sterile drapes, prepare the syringe, and prepare the US probe as described above. Infiltrate local anesthetic solution subcutaneously in the area overlying the foreign body. Align the long axis of the US probe with the long axis of the foreign body. Insert a 27 gauge needle in front of the US probe. Slowly advance the needle under US guidance until its tip is against the foreign body. Release the needle with the dominant hand and grasp a #11 scalpel. Insert the #11 scalpel blade along the needle until the tip of the blade is at the tip of the needle. Remove the scalpel blade and needle without moving the US probe. Insert a forceps, hemostat, or alligator forceps along the incision track under US guidance. Open the instrument, grasp the foreign body, and remove it.
ASSESSMENT It is important to rescan the area after removal of the foreign body to ensure there is no additional foreign body or a retained piece of the original foreign body which needs to be retrieved. Foreign bodies may not be removed in their entirety. A second foreign body may be present in an injury and not visible on the initial US scans.
AFTERCARE Ensure that the foreign body is completely removed. There are many different thoughts on the care of wounds. Copiously irrigate the area. A review of the Cochrane Database indicates that there is no evidence that using tap water to cleanse acute wounds in adults increases infection; while some evidence suggests that it reduces infection rates.42 There is no strong evidence that cleansing wounds per se increases healing or reduces infection.42 Close any lacerations from the wound itself or from the procedure to remove the foreign body. There is no strong evidence to support the use of antibiotics in simple non-bite wounds.43 Wounds associated with foreign bodies are at an increased risk for infection. Instruct the patient to be aware of the signs and symptoms of an infection. In one review, 44.4% of all subjects with a foreign body removed were prescribed antibiotics.44 However, when consultants were utilized in the care of these patients, this number rose to 84.4%.44 A short course of antibiotics may be appropriate to prevent iatrogenic septic complications or sequelae caused by mobilization of the foreign body.45
99
Tick Removal Zach Kassutto
INTRODUCTION Ticks are blood-feeding external parasites (Figure 99-1). Ticks are a significant infectious disease problem in the United States as well as worldwide. They have been implicated as vectors in the transmission of many diseases including Lyme disease, ehrlichiosis, babesiosis, Rocky Mountain spotted fever, tularemia, tick paralysis, and tick-borne relapsing fever. Disease transmission is postulated to occur when stomach contents and saliva from the tick are introduced into the host during the blood-feeding process. There is significance in how long a tick has been attached and how quickly a feeding tick can be removed to the transmission of tick-borne diseases. Early removal is felt to limit the transmission of disease. For example, current entomological thinking suggests that the tick must be attached for at least 24 hours in order to transmit B. burgdorferi, the spirochete responsible for Lyme disease.1
ANATOMY AND PATHOPHYSIOLOGY There are two main families of ticks.2 Hard body ticks belong to the Ixodidae family. Soft body ticks belong to the Argasidae family. Hard body ticks are responsible for the transmission of the majority of human diseases and will be the focus of this chapter. Hard ticks pass through four life cycle stages from birth (egg, larva, nymph, and adult). They require a blood meal in order to progress into the next stage of their development. The bite of a tick is painless and often goes unnoticed unless the tick is found attached to the skin. Ticks are often encountered in the late spring, summer, and early fall. Ticks are more prevalent in rural and wooded areas. They like to feed in dark (covered) and moist areas of the body such as the axilla, groin, or scalp. Ticks have specialized mouthparts that make their removal difficult (Figure 99-2).2 They screw their mouthparts into the skin in a clockwise direction. Mouthparts include the palps, the chelicerae, and the hypostome. The chelicerae are used to cut through the host’s epidermis and allow passage of the tick’s hypostome, through which the feeding takes place. Ticks attach themselves to their host by inserting the rod-like hypostome into the skin. The hypostome
COMPLICATIONS Foreign bodies, as well as the procedures to remove them, have been associated with infections (e.g., flexor synovitis, cellulitis, gas gangrene, abscesses, osteomyelitis, fungal infections, and lymphangitis), laceration of adjacent structures (e.g., nerves and tendons), neuropraxia, inclusion cysts, fractures, arthritis, and even an angiosarcoma.13,23,40,46,47 Even though attempts are made to identify and remove all foreign bodies, some of them may be missed. A retained foreign body can lead to similar symptoms at a later time.48 Therefore, it is important to investigate and remove foreign bodies in a timely manner.
SUMMARY Foreign bodies are a major source of physician litigation. They are often not detected on standard radiographs and can be associated with complications. A high index of suspicion must be maintained when the patient has a laceration, soft tissue mass, or foreign body sensation. US can be used to identify and guide the removal of foreign bodies in the Emergency Department.
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FIGURE 99-1. The tick.
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Hypostome Palp
Cement
Epidermis Dermis
Optional Equipment • Magnifying headlamp • 18 gauge needle • Local anesthetic solution • 3 mL syringe with a 27 gauge needle • Skin biopsy punches • #15 surgical scalpel blade on a handle • 5-0 nylon suture • Specimen container with isopropyl alcohol • Commercial tick removal device10
PATIENT PREPARATION
FIGURE 99-2. The specialized mouthparts of the tick.
has many backward pointing sharp barb-like projections that prevent it from being pulled out. Additionally, some ticks secrete a cement-like material around the hypostome to secure its attachment to the host while it feeds. The longer the tick is attached, the more difficult it becomes to remove it intact. The tick releases its mouthparts from the host after the meal is complete. It can take anywhere from hours to days for an adult tick to finish its blood meal and detach from its host.4
Explain the risks and benefits of the procedure to the patient and/or their representative. Risks include failure to remove all tick parts and infection. Obtain an informed consent for the procedure. Clean any dirt and debris from the skin. Apply povidone iodine or chlorhexidine solution to the skin surrounding the tick and allow it to dry. An alcohol swab can be used as a substitute.
TECHNIQUE
There are no absolute or relative contraindications to the removal of a tick.
Direct mechanical removal of the tick is the only recommended technique.4 Grasp the tick tightly with a fine forceps or mosquito hemostat at the tick’s head or mouthparts, as close to the patient’s skin as possible (Figure 99-3A). Do not crush, puncture, squeeze, or tear the ticks’ abdomen. Apply firm and upward pressure to remove the tick (Figure 99-3B). Carefully examine the skin for any remaining portions of the tick’s mouthparts. Gently grasp and remove any retained parts of the tick with a fine forceps or tease them out with the tip of a sterile needle. Direct traction is the preferred method, although some have suggested that a rotary counterclockwise movement combined with the firm pull may be more effective.4 Another technique that has been described suggests first rotating the tick two complete revolutions around its axis to loosen its attachment prior to pulling it away from the skin.5 The premise is that the twisting action will disengage the tick’s mouthparts. There is not enough information to recommend or refute these methods.
EQUIPMENT
ALTERNATIVE TECHNIQUES
Required Equipment • Povidone iodine solution, chlorhexidine solution, or isopropyl alcohol swabs • Gloves • Fine forceps or mosquito hemostat
Some Emergency Physicians prefer a surgical technique to remove the tick and its attachment to the skin to ensure that no fragments of the tick mouthparts remain within the patient. Clean and prep the skin. Inject 0.25 to 0.50 mL of local anesthetic solution subcutaneously immediately underneath the tick’s mouthparts. Apply povidone iodine or chlorhexidine solution to the skin and allow it to
INDICATIONS Any tick found attached to the skin should be removed. Transmission of bacteria, spirochetes, viruses, or other infectious agents is directly related to length of time of attachment. Ticks attached less than 24 hours are very low risk for transmission of disease.3
CONTRAINDICATIONS
FIGURE 99-3. Removal of the tick. A. The tick is grasped as close to the skin as possible. B. Firm upward pressure is applied to remove the tick.
CHAPTER 100: Fishhook Removal
dry. Stretch the skin on each side of the tick with the nondominant hand. Apply the skin biopsy punch perpendicular to the skin. Make sure that the tick is centered within the skin biopsy punch. Advance the skin biopsy punch downward using a twisting (clockwise– counterclockwise) motion until a loss of resistance is felt. The loss of resistance indicates that the skin biopsy punch is through the epidermis and at the level of the dermis. Remove the skin biopsy punch. Grasp and lift the punched skin plug with a forceps. Cut the plug at the dermal-epidermal junction with an iris scissors or a #15 scalpel blade. Alternatively, remove the tick and skin with a #15 surgical scalpel blade. At the Emergency Physician’s discretion, close the skin site with a single 5-0 nylon suture or leave it open to granulate and heal. Patients or their family members may use variety of folk/home therapies in their efforts to either passively or actively remove ticks. Techniques that involve coating the tick with noxious materials such as kerosene, lidocaine, or nail polish to cause the tick to voluntarily withdraw its attachment have not been shown to be successful.4,6 Techniques that attempt to suffocate the tick with petroleum jelly are also not felt to be useful due to the low respiratory rate of 3 to 10 breaths per hour in a feeding tick.5 The use of a heated object, e.g., a match tip or piece of metal, applied to the abdominal surface of the tick has not been shown to effect rapid tick detachment and presents a risk of burning the patient. Subcutaneous injection of local anesthetic solution at the attachment site was studied and was found to be ineffective in stimulating tick detachment.7 There are specific devices that are commercially available and advertised to aid in manual tick removal. Some of these devices have been tested and are not felt to offer any advantage over forceps removal.8–10
ASSESSMENT After removing the tick, carefully inspect the bite site to ensure no foreign material has been retained. Ticks can usually be discarded as testing of the tick is usually not indicated. If testing is desired, place the tick in a specimen container with isopropyl alcohol until testing can be performed by a laboratory or the local public health department.
AFTERCARE Cleanse the area with a mild disinfectant or soap and water. Administer tetanus prophylaxis if the patient’s immunization history is not up-to-date. The appearance of any rash or the occurrence of any febrile illness 2 to 12 days after a documented tick exposure should prompt further medical follow-up. Provide the patient information regarding the signs and symptoms of Lyme disease and/or other tick-borne diseases seen in your specific geographical area. The patient should inspect the site twice a day for signs of an infection. They should return to the Emergency Department or their Primary Care Physician if they develop redness, tenderness, swelling, a discharge, or a rash at the bite site. A detailed discussion identifying the types of ticks or the indications for prophylactic antibiotic therapy is beyond the scope of this chapter. Consult the current medical literature or an Infectious Disease Specialist regarding these questions. The use of prophylactic oral antibiotics to cover typical skin flora or Lyme disease is not routinely recommended. If antibiotics are prescribed, options include 5 to 7 days of: doxycycline (100 mg bid), tetracycline (500 mg qid), amoxicillin-clavulanate (400 to 875 mg bid), levofloxacin (500 mg qd), or erythromycin (125 to 500 mg qid). Do not prescribe doxycycline, tetracycline, or levofloxacin in children and pregnant women to avoid associated complications. Patients should be educated about ticks and preventative measures to avoid tick bites. Prevention is the best protection. When
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outdoors, patients should be advised to wear clothes to cover their arms, legs, and torso; tuck the cuffs of pants into boots; apply a repellent (chemical or botanical in origin) or an insecticide to clothes and exposed skin; and physically check for the presence of ticks at the end of the activity or the end of the day.
COMPLICATIONS The major complication of the direct removal technique is the separation of the tick body from the embedded head. Leaving foreign material in the wound can serve as a site for subsequent infection.5 Any remaining pieces of the tick should be removed using an 18 gauge needle, a skin biopsy punch, or sharp dissection with a #15 scalpel blade. Inadvertent crushing of the tick may allow stomach contents or saliva from the tick to enter the wound. It is theorized that grasping the tick too distal to its head, across its thorax/abdomen, could induce regurgitation of stomach contents into the wound and increases the risk of disease transmission.5 Local complications include bleeding and infection. The application of direct pressure will control any bleeding. A cellulitis presents a few days after the bite and is often due to the ticks feeding process, skin contamination entering the bite site, or retained mouthparts. Carefully inspect the bite site to ensure there are no retained mouthparts. If unsure, use a skin biopsy punch to remove the bite site. Treat the cellulitis with oral antibiotics that cover typical skin flora.
SUMMARY Ticks are a vector for numerous serious diseases and should be removed from the skin as soon as they are identified. Disease transmission is felt unlikely if the tick has been attached less than 24 hours. The only recommended technique for tick removal is manual detachment using forceps.
100
Fishhook Removal Eric F. Reichman and Renee C. Hamilton
INTRODUCTION Depending on practice location and season of the year, the presentation of a fishhook embedded in the subcutaneous tissue can be common. The patient or a well-meaning bystander will often have already attempted removal that was prevented by the hook’s barb. The ensuing tissue trauma and patient anxiety can complicate the task for the Emergency Physician. Removal can be difficult as a fishhook is designed not to pull out of a fish’s mouth. Several methods of removal have been described.1–9 The method chosen depends on the type and size of the hook, the depth of penetration, and the anatomical location of injury.
ANATOMY AND PATHOPHYSIOLOGY Most fishhooks become embedded in the skin and subcutaneous soft tissue. The anatomy of a fishhook is simple (Figure 100-1). The long, straight section is known as the shaft. The proximal end of the shaft has a closed circle, the eyelet, where the fishing wire attaches. The distal end of the shaft curves in a semicircle known as the belly of the fishhook. The belly tapers into a sharp point with a barb. The
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• • • • • • • •
Wire cutter Needle driver Hemostat 18 gauge needle #11 scalpel blade on a handle String, fishing line, or a strong silk tie, at least 50 cm in length Tongue depressors Safety glasses/goggles or a face mask with an eye shield
PATIENT PREPARATION FIGURE 100-1. Anatomy of a fishhook.
barb is usually located on the inner surface of the hook, pointing away from the tip. The barb, once pierced through the skin, becomes embedded within the tissue and prevents removal of the fishhook. Additional barbs may be located along the shaft of the fishhook.
INDICATIONS Any embedded fishhook must be removed from the body. There is no reason a fishhook should not be removed by the Emergency Physician if no contraindication exists.
CONTRAINDICATIONS There are no absolute contraindications to fishhook removal. Occasionally, the procedure should be referred to a consultant. Globe perforation or laceration requires emergent consultation with an Ophthalmologist. Place the patient supine with a shield, not a patch, over the eye. Please see Chapter 161 for the complete details regarding eye patching and eye shields. Penetration of, or near, vital structures (e.g., the neck, groin, or major neurovascular structures) should be given consideration for the appropriate surgical consultation prior to removal of the fishhook.
EQUIPMENT • Povidone iodine or chlorhexidine solution • Local anesthetic solution without epinephrine • 3 mL syringe armed with a 25 gauge needle
Explain the risks and benefits of the procedure to the patient and/ or their representative. Ask the patient to describe the type of fishhook embedded, especially in regards to the number and location of the barbs. Ask the patient to draw a picture of the fishhook or provide you with a similar one to examine. The number and location of the barbs will help in determining the appropriate removal technique. Obtain a signed consent form prior to beginning the procedure. Cleanse the skin of any dirt and debris. Apply povidone iodine or chlorhexidine solution to the skin surrounding the embedded fishhook and allow it to dry. The Emergency Physician should wear eye protection when removing a fishhook to prevent injuring themself. At minimum, wear safety glasses or goggles. If available, a face mask with an eye shield is preferred.
TECHNIQUES PULL-THROUGH TECHNIQUE This is the traditional method that is used for larger sized hooks embedded in the soft tissue with the barb near the skin surface. This is the preferred technique for fishhooks embedded in the ear, a joint, or in the nasal cartilages. Experienced fishermen often perform this technique in the field, as they would hate to lose prime fishing time to go to the Emergency Department. Identify the barbed end of the fishhook, located under the skin surface. Inject 0.5 to 1.0 mL of local anesthetic solution into the subcutaneous tissue overlying the barbed end of the fishhook to raise a skin wheal (Figure 100-2A). Allow 3 to 4 minutes for the local anesthetic solution to take effect. Grasp the shaft of the fishhook with a needle driver (Figure 100-2B). Advance the fishhook until the barbed end protrudes through the anesthetized skin (Figure 100-2B). Securely clamp a hemostat over the barb. This
FIGURE 100-2. The pull-through technique for fishhook removal. A. Subcutaneous anesthetic is placed over the barb. B. The fishhook is advanced until the barb protrudes from the skin. C. A hemostat is placed over the barb before it is cut off with wire cutters. D. The fishhook is removed.
CHAPTER 100: Fishhook Removal
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FIGURE 100-3. An alternative pull-through technique for the removal of a multibarbed fishhook. A. Subcutaneous anesthetic is placed over the barb. B. The fishhook is advanced until all of the proximal barbs are under the skin. C. The shaft is cut. D. The fishhook is removed.
will prevent it from becoming a projectile when cut and injuring someone. Cut the belly of the fishhook just proximal to the barbed end with a wire cutter (Figure 100-2C). Grasp the shaft of the fishhook with the needle driver and withdraw it along its direction of entry (Figure 100-2D). Occasionally, fishhooks may have additional barbs on the shaft or the belly (Figure 100-3). Inject 0.5 to 1.0 mL of local anesthetic solution into the subcutaneous tissue overlying the barbed end of the fishhook (Figure 100-3A). Allow 3 to 4 minutes for the local anesthetic solution to take effect. Grasp the shaft of the fishhook with a needle driver (Figure 100-3B). Advance the fishhook until the barbed end protrudes through the anesthetized skin (Figure 100-3B). Continue to advance the fishhook until all the barbs on the belly and shaft are below the skin surface (Figure 100-3B). Securely clamp a hemostat over the proximal shaft of the fishhook (Figure 100-3C). Cut the shaft of the fishhook at the level of the skin with a wire cutter (Figure 100-3C). Grasp the fishhook just proximal to the barbed end with the needle driver and pull the remainder of the fishhook out of the tissues (Figure 100-3D).
BARB-SHEATH TECHNIQUE This method is reserved for small fishhooks embedded near the skin surface. This technique should not be used for fishhooks in the ear, nose, or a joint cavity. Inject 0.5 to 1.0 mL of local anesthetic solution to form a wheal subcutaneously around the area where the fishhook enters the skin. Insert an 18 gauge needle along the entrance wound and aimed toward the barb (Figure 100-4A). The bevel of the needle should face the barb with the goal being to engage and cover the barb. Advance the needle and engage the barb in the core of the needle (Figure 100-4B). Gently twist and pull the hook back through the entrance wound while the needle covers the barb (Figure 100-4C).
An alternative method is to insert a #11 scalpel blade parallel to the shaft of the fishhook at the site it enters the skin. Advance the scalpel blade until it is adjacent to the barb. Withdraw the fishhook and scalpel through the tract. The barb will be resting against the scalpel blade and not get embedded in the subcutaneous tissues. This method is not recommended due to the blind insertion of a scalpel blade into the soft tissues and the potential for secondary injury.
STRING-YANK TECHNIQUE This method has been extensively described and is often performed by experienced fishermen in the field. It is rapid, effective, easy to perform, and relatively painless. This technique should not be used for fishhooks in the ear, nose, or a joint cavity. The Emergency Physician should take caution for themselves, the patient, and bystanders. The hook often forcibly flies out of the patient. Ensure the suspected path of the fishhook is clear. Eye protection is recommended with this technique for both the Emergency Physician and the patient. Place the body part that the fishhook entered firmly on a flat surface. Local anesthetic solution can be infiltrated, at the Emergency Physicians discretion, into the area where the fishhook enters the skin. Wrap the midpoint of a long string around the belly of the fishhook at the site it enters the skin (Figure 100-5A). The string ends should be firmly wrapped around and secured to the index and middle fingers of the Emergency Physician’s dominant hand. Use the gloved nondominant thumb or index finger to firmly depress the shaft of the fishhook against the skin, until slight resistance is met (Figure 100-5B). The shaft should be parallel to the skin and touching the skin. This will disengage the barb from the soft tissues. Quickly and firmly jerk the string (Figure 100-5C). This maneuver will release the fishhook from the subcutaneous tissues and pull it out through the entry wound.
FIGURE 100-4. The barb-sheath technique for fishhook removal. A. Insert the needle through the entrance wound and aimed toward the barb. B. Advance the needle through the entry site to catch the barb in the core of the needle. C. The needle and fishhook are removed as a unit.
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FIGURE 100-5. The string-yank technique for fishhook removal. A. A string is wrapped around the belly of the fishhook. B. The shaft of the fishhook is depressed until resistance is encountered. The shaft should be parallel to the skin and touching the skin. C. A quick tug on the string will remove the fishhook.
Alternatively, the Emergency Physician may use two tongue depressors to provide secure traction to the string. Wrap each end of the string around one tongue depressor. Instruct an assistant to gently depress the fishhook shaft against the skin while the Emergency Physician jerks the string.6
AFTERCARE
SUMMARY Fishhook removal can be accomplished by one of several simple techniques. It can be performed in the Emergency Department, the office, or the field with minimal supplies. Almost painless removal is possible in most cases. This procedure is gratifying both for the patient and the Emergency Physician.
The wound should be cleaned of any blood and a dry dressing applied. Administer tetanus prophylaxis if the immunization history is not up-to-date. A radiograph is indicated if there is any suspicion of a retained foreign body. Acetaminophen or nonsteroidal anti-inflammatory drugs will provide any required analgesia. Instruct the patient to clean the area with warm soapy water three times a day and to keep the wound covered until healed. Instruct the patient as to the signs of infection. They should return to the Emergency Department, or their physician, if signs of an infection develop. Routine follow-up is often not required unless the fishhook penetrated the ear, nose, or a joint. Antibiotic prophylaxis remains controversial.1,2 The use of antibiotics is left to the discretion of the Emergency Physician and should include consideration for the anatomic site of injury, depth of penetration, evidence of gross contamination, and factors that may compromise the patient’s immunity (e.g., diabetes mellitus, HIV infection, steroid use, or malignancy). If antibiotic prophylaxis is chosen, prescribe a broad spectrum antibiotic such as trimethoprim-sulfamethoxazole or doxycycline. These will provide good coverage against gram-negative organisms typically associated with water recreation injuries, as well as some coverage against MRSA and other community acquired infections.7 Adding ciprofloxacin for pseudomonas coverage may also be considered, as pseudomonas and its subtypes are commonly found in soil and freshwater.6
The need to remove a ring is not uncommon in the Emergency Department. Patients may present with an initial primary complaint that they can no longer remove a ring or that a ring has become painful. A variety of conditions may necessitate the urgent removal of a ring, including swelling from extremity trauma, infections or burns, increases in total volume status, and allergic reactions. Swelling of the digit can rapidly progress, causing the ring to become a constricting band and compromise blood flow to the digit. Critically ill patients undergoing admission to intensive care settings or emergency surgery may need to have rings removed urgently. The Emergency Physician’s goal is to remove the ring in a timely manner and not cause additional injury. The information in this chapter applies to rings on the fingers and toes.
COMPLICATIONS
ANATOMY AND PATHOPHYSIOLOGY
Complications include infection or damage to the surrounding tissue. Infection is often due to either the contaminated fishhook inoculating the tissues or the fishhook penetrating contaminated skin. Using proper removal techniques will minimize, but not eliminate, any damage to the soft tissues. Use caution when extracting fishhooks to avoid secondary injury to bystanders, the patient, or the Emergency Physician. Protective eyewear should be worn with all three techniques of fishhook extraction. Ocular injury has been reported to occur during this procedure.2 Fishhooks have been surgically extracted from the hypopharynx and the intestine.8,9 A surgical face mask with a face shield is another mode of protection that we recommend. When using the pull-through technique, clamping a hemostat to the exposed portion of the fishhook that is to be cut off will prevent flying shrapnel.
The second through fourth digits receive their blood supply through four vessels: the palmar radial digital arteries, the palmar ulnar digital arteries, the dorsal radial digital arteries, and the dorsal ulnar digital arteries. The thumb receives its blood supply from the dorsalis pollicis and princeps pollicis arteries. Blood returns from the digits via the dorsal digital veins. When the digit is compressed for prolonged periods by a tight-fitting ring, which acts as a tourniquet, venous return is impeded and swelling ensues. The swelling results in greater compression and further propagation of this cycle. In theory, the increased swelling will eventually impede the arterial supply to the digit. The greatest circumference of the finger is at the proximal interphalangeal (PIP) joint. Rings usually become entrapped proximal to the PIP joint. Skin breakdown and tissue necrosis occur if the constricting ring is not removed. Left untreated, the digit is at risk
101
Ring Removal Steven H. Bowman
INTRODUCTION
CHAPTER 101: Ring Removal
for infections such as cellulitis, tenosynovitis, and osteomyelitis. In severe cases, the digit’s viability may be threatened. There are several case reports of rings that have become embedded in the soft tissue of the digits.1–5 Most patients will experience pain and seek medical attention prior to the development of severe complications. Patients with an altered mental status, psychiatric illness, peripheral neuropathies, peripheral vascular disease, or other chronic disability may present later with complications.1,2,4,5
INDICATIONS Rings are usually removed to prevent ischemia of a digit. Remove a ring if the digit shows any signs of neurovascular compromise such as decreased capillary refill, decreased pulse wave on pulse oximetry, mottling, paleness, paresthesias, or diminished sensation. Rings should be removed whenever patients complain that a ring is causing pain. Generally, even a tight-fitting ring will not be painful. Rings must be removed from any injured digit where edema is a possible consequence. Examples include sprains, contusions, fractures, lacerations, crush injuries, and burns. Rings should be removed from all digits on the involved side for any extremity injury above the digits and where edema of the distal extremity is a possible consequence. Other nontraumatic conditions that may necessitate emergent ring removal include infections of the upper or lower extremity, acute increases in volume status, and allergic reactions. A patient may present and request a ring be removed that is tight and can no longer be taken off. Consider the need for urgent ring removal with markedly decreased levels of consciousness and in all critically ill patients, particularly those being admitted to intensive care settings or undergoing emergent surgery.
685
Glove Technique • Rubber gloves • Lubricant (K-Y jelly, Surgilube, petrolatum, mineral oil, or liquid soap) • Mosquito hemostat • Scissors Ring Cutter Technique • Ring cutter, manually operated or battery-powered • Steinman pin cutter if a ring cutter is not available • Two large hemostats or needle drivers • Pliers (optional) Vice-grips Pliers Technique • Medium size vice-grip pliers Miscellaneous Supplies • Ice water • Penrose drain or IV tourniquet • Basin or zip-lock bag for ice water
PATIENT PREPARATION
Metacarpal Block • Povidone iodine or chlorhexidine solution, or an isopropyl alcohol swab • 3 mL syringe • 25 or 27 gauge needle, 1 in. long • 3 to 5 mL local anesthetic solution without epinephrine
Place the patient sitting upright or in a semi-recumbent position. Position their hand on a bedside procedure table. Explain the procedure to the patient and/or their representative. A signed informed consent is not required for the removal of a ring. Analgesia should be provided in the form of a metacarpal block for patients who are complaining of pain. Refer to Chapter 126 for the complete details regarding a metacarpal block. The removal of a tight ring should be considered a two-step process: first reduce the edema in the finger, then remove the ring.6 Instruct the patient to elevate the affected hand or foot to reduce edema prior to any attempts at ring removal. Use a finger trap to elevate the affected extremity if the patient has difficulty or cannot keep the extremity elevated. Consider soaking the hand or foot in ice water for 5 to 10 minutes to reduce edema. A Penrose drain, piece of tape, gauze, or elastic bandage can be wrapped around the finger, from distal to proximal, to further reduce swelling. The simplest and most effective way to remove a ring from a finger is simply to cut the ring using a ring cutter. Reassure the patient that cut rings can be repaired by a jeweler. However, patients may still be reluctant to have expensive rings or rings with sentimental value removed in such a way. The practitioner must consider time, the individual circumstances regarding the entrapment, and which alternative techniques may be effective.
Lubricant and Caterpillar Techniques • Lubricant (K-Y jelly, Surgilube, petrolatum, mineral oil, or liquid soap)
TECHNIQUES
CONTRAINDICATIONS There are no absolute contraindications to removing a ring. It is important to note that certain techniques may be more applicable than others, depending on the individual patient.
EQUIPMENT
String Technique • String (1-0 silk suture, cotton umbilical string, tracheal tape, Penrose drain, or intravenous tourniquet) • Mosquito hemostat Rubber Band Technique • 3 to 4 mm wide rubber band • Lubricant (K-Y jelly, Surgilube, petrolatum, mineral oil, or liquid soap) • Mosquito hemostat
LUBRICANT TECHNIQUE This technique works for mild cases of ring entrapment with minimal swelling and without significant trauma. Many patients will attempt to remove the ring using some type of lubricant at home prior to presenting to the Emergency Department. Despite this, the same technique may also be tried in the Emergency Department prior to attempting other techniques. Liberally apply a lubricant (e.g., K-Y jelly, Surgilube, petrolatum, mineral oil, or liquid soap) to the digit and beneath the ring. Attempt to advance the ring over the PIP joint with steady traction.
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FIGURE 101-2. The string technique. A. A string is passed between the ring and the finger. B. The string distal to the ring is wound tightly around the finger and continued distally to the level just below the PIP joint. C. The string proximal to the ring is slowly unwound and moves the ring distally. D. When the ring passes the PIP joint, it usually comes off without effort.
FIGURE 101-1. The caterpillar technique. A. The entire finger is lubricated. B. The ring has been pushed down the proximal phalanx until it reaches the PIP joint. Push the bottom of the ring up firmly while maintaining pressure. C. Swing the top portion of the ring distally over the joint while maintaining upward pressure. D. Push down firmly while maintaining downward pressure. E. Swing the bottom portion of the ring proximally over the joint and remove the ring.
CATERPILLAR TECHNIQUE This recently described technique is useful in that it requires no additional materials other than lubricant (Figure 101-1).7 Liberally apply a lubricant to the finger (Figure 101-1A). Slide the ring down the proximal phalanx and just proximal to the PIP joint. Apply and maintain upward pressure on the bottom of the ring (Figure 101-1B). Simultaneously swing the upper portion of the ring distally (Figure 101-1C). Pull the top of the ring over the PIP joint. Apply and maintain downward pressure on the top of the ring (Figure 101-1D). Simultaneously swing the lower portion of the ring distally to free it (Figure 101-1E). Remove the ring from the finger. This “caterpillar motion” allows the ring to be slowly advanced distally and ultimately removed.
STRING TECHNIQUE Several authors have extensively described the string technique and its modifications5,6,8,17 (Figure 101-2). This technique consists of using a “string” to compress the edematous tissue, exsanguinate the digit, and then facilitate the passage of the ring over the PIP joint. This technique should be avoided if the patient has an associated finger laceration, finger fracture, or an embedded ring.8,9
Pass a length of 1-0 silk suture or a piece of string underneath the ring (Figure 101-2A). Avoid monofilament sutures and smaller-size sutures as they may break or inadvertently cut the patient if wound too tightly. Passage of the string or suture may be facilitated with the use of a mosquito hemostat.8–10 Wind the distal portion of the suture tightly around the digit in a closed spiral (Figure 101-2B). There should be no interposition of skin between the turns of the suture material so as to ensure even compression of the skin and soft tissue. Continue the spiral distally to just beyond the PIP joint. Grasp the proximal end of the suture. Unwind the suture while maintaining traction in the distal direction (Figure 101-2C). The ring will be pushed distally as the suture unwinds. The ring is easily removed once it clears the PIP joint (Figure 101-2D). Other materials—such as umbilical tape, cotton gauze, rubber intravenous tourniquets, or Penrose drains—have also been used.6,11,12 These materials have certain practical advantages. Since they are wider than sutures, shorter lengths and fewer turns are required to encircle the finger. It is easier to wind these materials around the digit without interposition of the skin between the turns (Figure 101-3). Insert the umbilical tape under the ring, from distal to proximal, with the aid of a mosquito hemostat (Figure 101-3A). Pull 6 to 7 cm of the umbilical tape proximal to the ring (Figure 101-3B). Wind the distal portion of the umbilical tape tightly around the digit in a closed spiral (Figure 101-3C). There should be no interposition of skin between the turns of the umbilical tape. Continue to spiral distally to just beyond the PIP joint (Figure 101-3C). Grasp the proximal end of the umbilical tape. Unwind the proximal end of the umbilical tape while maintaining traction in a distal direction
CHAPTER 101: Ring Removal
687
FIGURE 101-3. The string technique with umbilical tape. A. The umbilical tape is inserted under the ring with a mosquito hemostat. B. The umbilical tape is pulled through to the other side of the ring. C. The umbilical tape distal to the ring is wound tightly around the finger to the level just below the PIP joint. D. The umbilical tape proximal to the ring is slowly unwound and moves the ring distally. E. The ring passes the PIP joint. F. The ring is free and usually comes off without effort.
(Figure 101-3D). Continue to unwind the umbilical tape until the ring passes the PIP joint (Figure 101-3E). The ring is easily removed once it clears the PIP joint (Figure 101-3F).
RUBBER BAND TECHNIQUE This technique utilizes a 3 to 4 mm wide rubber band, which is used to apply traction on the ring to facilitate its passage over the PIP joint10 (Figure 101-4). Though success has been reported using rubber bands, this technique should be reserved for less severe ring entrapments. Avoid this technique if the patient has a laceration, a fracture, or an embedded ring. Lubricate the finger liberally, as described above. Pass the rubber band beneath the ring using a mosquito hemostat (Figures 101-4A & B). Position the rubber band so that equal lengths are on each side of the ring (Figure 101-4C). Insert a finger through both loops of the rubber band (Figure 101-4D). Pull the loops of the rubber band distally while simultaneously moving them circumferentially between the ring and the finger (Figure 101-4D). Continue the motion until the ring is removed (Figure 101-4E).
GLOVE TECHNIQUE This technique has been advocated for use in patients with underlying soft tissue injury to the finger.13,14 Its success is anecdotal. The glove technique uses a finger cut from an appropriately sized rubber glove (Figure 101-5). The glove finger provides mild compression, acts as a barrier to protect damaged soft tissue, and provides a “leading edge” to guide the ring over the damaged tissues. Despite these theoretical advantages, the glove technique may be no more effective than any other in cases of severe finger edema.
Choose a glove that fits the patient snugly. Use the patient’s other hand to aid in choosing the right size glove. Cut the finger from a glove to match the finger of the patient (Figure 101-5A). Cut off the tip of the finger of the glove to create a cylinder (Figure 101-5A). Slide the cylinder onto the patient’s finger. Advance the proximal portion of the cylinder beneath the ring using a mosquito hemostat (Figure 101-5B). Lubricate the cylinder and the ring with K-Y jelly, Surgilube, petrolatum, mineral oil, or liquid soap. Pull the proximal edges of the latex cylinder distally, with your fingers or mosquito hemostats, to advance the ring distally (Figure 101-5C). Continue to pull on the proximal cylinder until the ring moves past the PIP joint and falls off the finger.
RING CUTTER TECHNIQUE The definitive method for ring removal is cutting the ring. The ring should be cut if the patient presents with an underlying injury, severe swelling, an embedded ring, or entrapment with nonjewelry items. Cutting a ring is generally rapid and safe. A ring cutter can be used to cut rings made of gold, plastic, platinum, silver, stainless steel, and titanium. Many devices will cut rings. The standard rotary ring cutter should be available in every Emergency Department (Figure 101-6). The ring cutter’s blade should be periodically inspected and it should be sharp. Battery-powered ring cutters are also available (Figure 101-7) (Mooney & Co., Ashland, OR). The advantage of the powered ring cutters is that they are easy to use, lightweight, fast, powerful, can easily cut nonjewelry items, and do not rely on the strength of the healthcare provider to use them. In the absence of a ring cutter, another medical device that has been used successfully to cut rings is the Steinman pin cutter.15 Our
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SECTION 7: Skin and Soft Tissue Procedures
FIGURE 101-4. The rubber band technique. A. A mosquito hemostat is passed below the ring and grasps the rubber band. B. The rubber band is pulled beneath the ring and out the other side. C. The rubber band is positioned with equal lengths of loop on each side of the ring. D. Both loops of the rubber band are grasped and pulled distally while it is simultaneously rotated circumferentially. E. When the ring passes the PIP joint, it usually comes off without effort.
Emergency Department also maintains a sharp pair of diagonal pliers that can be effective at cutting small rings. Pass the finger guard of the ring cutter between the ring and the digit at the thinnest part of the ring (Figure 101-8). Care should be taken to place the ring cutter correctly and avoid additional injury. The ring may be squeezed using a heavy needle driver, hemostat, or pliers to change its shape from round to oval to facilitate passage of the finger guard (Figure 101-9). This additional distortion of the ring will not further exacerbate the entrapment.15 Lower the cutting blade onto the ring. Turn the turn key to rotate the blade while maintaining pressure on the ring. Continue turning the turn key until the blade completely cuts through the ring. Pry the ring open with two hemostats or needle drivers once it is completely cut through and remove the ring. An alternative to one cut and prying the ring open is to make two cuts on opposite sides of the ring so that it falls apart in two pieces. If an open wound is present, it should be irrigated with normal saline to remove any small metal fragments that may result from the cutting process. There has been a case report of a foreign body granuloma caused by metal particles left in a finger wound in a patient following ring removal.16
VICE-GRIP PLIERS TECHNIQUE
FIGURE 101-5. The latex glove technique. A. The finger matching the one on which the ring is lodged is cut from an examination glove. B. The latex cylinder is put on the finger. The proximal edges of the cylinder are pulled under and proximal to the ring using a mosquito hemostat. C. The proximal edges of the latex cylinder are slowly pulled distally to roll the ring off the finger.
Many rings cannot be removed with the previously described techniques. These rings can be of a material that also cannot be cut with a carbide, diamond, or metal cutting disk on a ring cutter. This includes rings made of ceramics, natural stone (e.g., jade or onyx), and tungsten carbide. These rings can be removed by cracking them into pieces in a controlled fashion using a vice-grip pliers. A medium-sized vice-grip pliers is usually appropriate for most ring sizes. Open the jaws of the vice-grip pliers. Adjust the
CHAPTER 101: Ring Removal
A
689
B
FIGURE 101-6. Manually operated ring cutters. A. Examples of manually operated ring cutters. B. The anatomy of a ring cutter.
tightening screw so that the closed jaws of the vice-grips fit over the ring (Figure 101-10). Close and clamp the vice grip so that the jaws close lightly on the ring. Release the jaws, turn the tightening screw one-quarter of a turn, and reclamp the jaws on the ring. Continue this process of releasing the jaws, turning the tightening screw one-quarter of a turn, and reclamping the jaws on different places of the ring each time until a crack is heard. Keep continuing this process of tightening the jaws and reclamping different areas of the ring until the ring breaks into pieces and falls off.
ALTERNATIVE TECHNIQUES
tools such as heavy-duty saws and bolt cutters may be needed to remove these objects. Battery-powered ring cutters may be ideal in these situations. Power saws and Dremel tools with carbon blades have been used to successfully remove hardened steel rings from a patient’s fingers.5 If it becomes necessary to use a powered metal cutting device, additional care should be taken to protect the patient from secondary injury from the cutting element and the heat these powered devices may generate.
ASSESSMENT
Patients may rarely present with other heavy circular objects on their digits such as steel rings, nuts, or washers that cannot be removed using a manually operated ring cutter. Powered cutting
Thoroughly examine the finger for any injuries after the ring is removed. Reassess perfusion to the digit by noting the capillary refill time, the color, and the pulse oximeter reading on the affected digit compared to adjacent fingers.
FIGURE 101-7. The GEM Ring Cutting System (Mooney & Co., Ashland, OR). A battery-powered and motorized ring cutter.
FIGURE 101-8. Ring removal using a manual ring cutter.
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Check that the proper cutting disk is on the ring cutter and that it is not dull or worn. Install fresh batteries or recharge them to maximize the power of the electric ring cutter. The ring, and the patient’s finger, can become quite hot and burn the patient. Periodically check the progress and make sure that the ring has not been cut and you are now cutting the finger guard. Using a cutting disk that is dull, worn, or incorrect can generate significant heat. Correct these issues. Submerge the finger in ice water for a few minutes then resume cutting the ring.
SUMMARY
FIGURE 101-9. A pair of pliers is used to make the ring “oval” in shape. This may facilitate the use of a ring cutter.
AFTERCARE No specific aftercare is required following the ring removal process. Elevation, nonsteroidal anti-inflammatory agents, and local wound care are all that is necessary. Consultation with a Hand Surgeon, Orthopedic Surgeon, Plastic Surgeon, or Podiatrist is recommended in severe cases that include embedded rings, infections, vascular compromise, and/or neurologic compromise. The aftercare is based on any lacerations and/or fractures of the digit. The patient’s tetanus immune status should be ascertained and, if the skin is broken, the appropriate tetanus prophylaxis administered. Instruct the patient not to place any rings on the digit until the edema has completely resolved. Place the ring, and any pieces, in a specimen container and return it to the patient.
COMPLICATIONS The direct complications of ring removal are minor compared to the complications that may occur from failure to remove a ring. Direct complications include secondary injury to soft tissues, vascular structures, and nerves and granuloma formation. This can be due to passing objects and instruments under an extremely tight ring or from improperly used instruments to remove the ring. Ring cutters have their own specific issues. It may cut too slowly. Ensure that you are using the proper cutting technique. The cutting disk may be worn, dull, or the wrong cutting disk for the material.
FIGURE 101-10. A vice-grip pliers can be used to remove hard or brittle rings.
Ring removal is a relatively straightforward and simple procedure. In situations in which the ring is extremely difficult to remove, a variety of potential approaches may assure success. Use of the ring cutter is the most reliable and quickest technique. The decision to use a ring cutter should be based upon the urgency with which the ring must be removed and not upon the monetary or sentimental value of the ring.
102
Subungual Hematoma Evacuation Steven H. Bowman
INTRODUCTION The fingertips are sensitive, mobile, and prone to injury. Blunt trauma to the tip of the finger or toe may result in a variety of injuries including fractures, avulsions to the nail and nail apparatus, contusions, lacerations, and amputations. The most common injuries to the distal fingers and toes are crush injuries. The most common mechanisms of injury are closure of some type of door (car, house, etc.) on the finger, dropped objects on the fingers or toes, hand tools, and power tools. Subungual hematomas often develop following blunt trauma to the distal finger or toe.1–3 They result from the accumulation of blood between the nail and the nail bed. Treatment of a subungual hematoma is relatively straightforward, yet in some cases it is still controversial. It is important to understand the structure of the distal finger or toe, to determine whether simple drainage will be sufficient management, and to consider how initial management may affect outcome.
ANATOMY AND PATHOPHYSIOLOGY The distal digits of the fingers and toes and the nail apparatus are complex structures (Figure 102-1). The perionychium is composed of the nail bed and the surrounding soft tissue. The hyponychium is the junction of the nail bed at the sterile matrix and the fingertip skin beneath the distal margin of the nail. The eponychium is the distal portion of the nail fold where it attaches to the proximal surface of the nail. The lunule is the white arc seen in the proximal portion of the nail. The nail bed consists of the germinal matrix on the proximal ventral floor of the nail fold and the sterile matrix, which extends from the lunule to the hyponychium. The germinal matrix is primarily responsible for the growth of the nail, with a significant contribution from the sterile matrix.4,5 The nail bed must be smooth for normal nail growth. A nail matrix that has not been well approximated to minimize scar formation may develop a deformed nail.1,3–8 The nail bed receives its blood supply from the two terminal branches of the volar digital artery, which communicate to form
CHAPTER 102: Subungual Hematoma Evacuation A
Lunule
Distal interphalangeal joint
B
Lateral nail fold Eponychium
Body of nail (nail plate)
Root of nail Proximal nail fold Nail matrix
Body of nail (nail plate)
Eponychium Lunule
Nail bed
Extensor digitorum insertion
to the injury itself and the increased pressure from the hematoma. The hematoma appears as a black-and-blue or black-and-purple area under the nail that is extremely tender to palpation. Nail bed injuries may be classified as simple lacerations, stellate lacerations, severe crush injuries, and avulsions.1 It is important to understand that each of these types of nail bed injuries may result in a subungual hematoma. The management of subungual hematomas is still somewhat controversial. The approach to management was initially very aggressive, since subungual hematomas are often seen with fractures of the distal phalanx, damage to the nail, and damage to the nail apparatus.1,2,4–8 The surgical literature generally recommends removal of the nail, inspection of the nail bed, and repair of any nail bed injury if the subungual hematoma involves 25% or more of the nail surface.1,2,4–9 This practice has been questioned recently by newer controlled studies that demonstrated excellent outcomes in patients with large (greater than 25%) subungual hematomas treated by trephination alone, regardless of the presence of fractures.11,12 Larger hematomas involving over 50% of the nail surface may be treated successfully with trephination. Many authors, primarily Hand Surgeons, still advocate the removal of the nail plate to thoroughly inspect the nail bed and effect repair in all patients who present with a subungual hematoma. Although this approach is time-honored, more recent studies have demonstrated that it is not necessary if the patient’s nail is still attached to the matrix, even in the presence of a distal phalanx fracture.11,12
INDICATIONS
Epidermis Flexor digitorum profundus insertion
691
Distal phalanx
FIGURE 102-1. The anatomy of the distal fingertip and nail bed. A. Surface anatomy. B. Midsagittal view.
blood sinuses. Venous drainage begins at the proximal portion of the nail bed and the skin proximal to the nail fold.4 Force applied to the tip of the finger or toe disrupts the vascular structures in the nail bed. Trauma causes the capillaries of the nail bed to be compressed between the nail and the distal phalanx. Blood collects between the nail bed and the nail, forming a subungual hematoma (Figure 102-2). The patient’s pain is directly related
Patients who present to the Emergency Department after sustaining an injury with a resultant subungual hematoma will generally complain of severe pain. Trephination, the process of making a small hole in the nail to allow the collected blood to escape, will provide significant relief for most patients.2,9 The trephination procedures described below should be utilized when patients present with a subungual hematoma and an intact (not fractured or avulsed) nail plate that is still attached to the matrix. If the nail plate is partially or completely avulsed from the matrix, simple evacuation of the hematoma may not constitute adequate therapy.9,10,11,13
CONTRAINDICATIONS Simple trephination is reserved for patients with intact nails. Patients who present with nail plate fractures, avulsions of the nail plate, disruption of the nail margin, or partial amputations may require more extensive therapy with removal of the nail plate and repair of the nail bed. A description of these techniques is provided in Chapters 96 and 104. Trephination using heat-based methods should be avoided in patients wearing artificial nails due to the potential for igniting the nail or nail adhesive.13 Subungual hematomas that extend proximal to the nail bed often represent proximal nail plate avulsions or injuries that require nail plate removal, nail plate repair or reinsertion, and nail bed repair.
EQUIPMENT
FIGURE 102-2. The subungual hematoma. A. Surface view. B. Sagittal view.
Digital/Metacarpal Block • Povidone iodine or chlorhexidine solution, or an isopropyl alcohol pad • 3 mL syringe • 25 or 27 gauge needle, 1 in. long • Local anesthetic solution without epinephrine
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SECTION 7: Skin and Soft Tissue Procedures
Electrocautery • Povidone iodine or chlorhexidine solution, or an isopropyl alcohol pad • Battery-powered electrocautery device Paper Clip Technique • Povidone iodine or chlorhexidine solution, or an isopropyl alcohol pad • Heat source (open flame) • Paper clip • Hemostat Drill Technique • Povidone iodine or chlorhexidine solution, or an isopropyl alcohol pad • 18 gauge needle • Cotton-tipped applicators The PathFormer (Path Scientific, Carlisle, MA) is an FDA approved device for nail plate trephination. It allows for the precise control of the depth of penetration while making a 400 µm diameter hole in the nail plate. The device is a battery-powered drill that automatically retracts the drill bit after the nail plate is penetrated. Thus, the sensitive and vascular nail bed is not contacted or injured. Unfortunately, the PathFormer device is not often available in Emergency Departments.
PATIENT PREPARATION Explain the procedure to the patient and emphasize that pain relief rapidly follows nail trephination. Obtain a consent to perform the procedure. Consider obtaining radiographs for significant traumatic injuries, suspected associated fractures, or any injury where the nail plate is damaged or avulsed. Place the patient in a sitting or semi-recumbent position on a gurney or multipositional procedure chair. Sit facing the patient. Place the hand with the injured digit palm side down on a flat surface such as a procedure table. Cleanse the injured digit of any dirt and debris. Apply povidone iodine or chlorhexidine solution over the nail plate and allow it to dry. An alcohol swab is an alternative to these solutions. Always allow the alcohol to dry before touching the nail plate with a hot object so that the alcohol does not ignite. A digital block is generally not needed if using heat-based methods to penetrate the nail plate.2,5,9,13 The nail plate is not innervated and the hematoma prevents contact with the nail bed. A digital block may be required if the patient is excessively anxious, if additional injury is present, or if a drill technique is to be performed. Refer to Chapter 126 for the complete details regarding digital and metacarpal blocks. An alternative to the digital block is to soak the affected finger in ice water for a few minutes prior to the procedure. The techniques described below may be used on fingernails and toenails.
FIGURE 102-3. The battery-operated electrocautery device.
cool for 1 to 2 seconds. This may prevent penetrating the nail plate too quickly and damaging the underlying nail bed. Place the hot tip on the nail plate, centered over the hematoma (Figure 102-4). Tap the nail plate several times with the cautery pen tip. Do not constantly hold the hot tip against the nail plate. The cautery tip will easily penetrate the nail plate. Do not plunge as the nail bed can be injured in addition to causing additional pain to the patient. Darkened blood will flow out of the hole when the hematoma is entered. The nail will regain its normal color after the hematoma is drained. Apply slight digital pressure to the nail plate to ensure complete drainage of the hematoma. The patient will usually begin to feel pain relief at this point. The tips of some microcautery devices are shaped in such a way that they will not make a hole that is wide enough to allow adequate drainage. Slightly rotate the cautery unit as it traverses the nail plate to ensure an adequate sized drainage hole of 3 to 4 mm. Some Emergency Physicians prefer to make an additional hole in the nail plate to ensure drainage if the first hole should become occluded.
TECHNIQUES ELECTROCAUTERY TECHNIQUE Electrocautery is the preferred technique to drain a subungual hematoma. Battery-operated microcautery devices are generally available in the Emergency Department (Figure 102-3). Assure the patient that they will not be burned. Stabilize the injured digit proximally with the nondominant hand. Grasp the cautery unit like a pencil with the dominant hand. Press the button on the cautery unit to heat the tip. Release the button and allow the tip to
FIGURE 102-4. The electrocautery technique. The hot tip of the unit is centered over the subungual hematoma and allowed to penetrate the nail plate.
CHAPTER 102: Subungual Hematoma Evacuation
693
FIGURE 102-5. The paper clip technique. The hot tip of the paper clip is centered over the subungual hematoma and allowed to penetrate the nail plate.
As an alternative to the single large hole, place three to four smaller drainage holes in the nail plate.
PAPER CLIP TECHNIQUE This technique is similar to that using the electrocautery unit. Unfold and heat the tip of a paper clip with a flame from a lighter or alcohol lamp. Place the heated tip of the paper clip against the nail plate, centered over the subungual hematoma (Figure 102-5). Apply slight downward pressure to allow the paper clip to perforate the nail plate. Do not plunge as the nail bed can be injured in addition to causing additional pain to the patient. A drop of blood will be seen as the paper clip enters the hematoma. Place at least one additional hole in the nail plate to ensure drainage if the first hole should become occluded. The paper clip will not get as hot as a cautery device. More than one attempt may be necessary to penetrate a thick nail. Another disadvantage of this technique is the possibility of introducing carbonaceous material into the hole. The use of an open flame may be potentially dangerous or prohibited in the Emergency Department.
DRILL TECHNIQUE This technique uses a needle as a small drill to penetrate the nail plate (Figure 102-6). Small electric nail drills are available that greatly simplify this procedure, though they may not be readily available in the Emergency Department. Drilling through the nail plate may require a digital block. This is particularly true if there is a fracture, another associated injury, or the nail plate is very thick. Grasp an 18-gauge needle by its hub with the dominant thumb and forefinger (Figure 102-6A). Place the tip of the needle over the nail plate, centered over the subungual hematoma. Spin the needle back and forth while applying gentle downward pressure. Small shavings will appear as the needle begins to drill through the nail plate. A loss of resistance will be felt as the hematoma is entered and darkened blood will flow from the hole. Do not plunge as the nail bed can be injured in addition to causing additional pain to the patient. Place at least one additional hole in the nail plate to ensure drainage if the first hole should become occluded. The editor uses a modified version of this technique (Reichman, personal communication). A cotton-tipped applicator may be wedged into the needle hub to facilitate the drilling (Figure 102-6B). This method makes the drilling more efficient, as the cotton-tipped applicator is easier to hold and offers a mechanical advantage when it is twisted. The drill technique is very useful in the absence of a heat-generating device.
FIGURE 102-6. Drill techniques. A. A twisting motion of the 18 gauge needle is used to penetrate the nail plate. B. A cotton-tipped applicator has been inserted into the hub of the needle. A twisting motion is used to penetrate the nail plate.
ASSESSMENT Gently compress the nail plate to evacuate the hematoma. Any underlying injury should be evaluated and managed.
AFTERCARE The patient should keep the wound clean and monitor drainage. The nail plate may be covered with a nonadherent dressing. The hematoma may continue to drain for several hours or up to 1 to 2 days. If there is a reaccumulation, denoted by the reappearance of darkened blood beneath the nail, the nail can be soaked in warm water and pressure applied to express the hematoma. Inform the patient that the discoloration under the nail plate can persist for several weeks. Also inform them that the nail plate may fall off and it can take up to 3 months for another nail plate to completely form. A splint should be applied if a distal phalanx fracture is present. No studies have demonstrated that prophylactic antibiotics are beneficial in the management of a subungual hematoma.9,14 The patient should immediately return to the Emergency Department or their primary physician for fever, increased pain, purulent drainage from the nail, or any redness or swelling of the digit.
COMPLICATIONS Direct complications from nail trephination are rare.11–13 Complications will more likely result from the original injury and include nail loss, nail deformity, cosmetic changes, and infection. Patients should be warned that as the nail grows out, loss of the nail is a possibility. The hematoma may reaccumulate if the hole in the nail is too small and becomes occluded. Reaccumulation can be
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prevented by making a large hole or multiple holes in the nail plate. Plunging through the nail plate with a cautery unit or needle will cause the patient pain and injury to the nail bed that may be permanent and result in a deformed nail plate.
A
Lunule
Distal interphalangeal joint
Lateral nail fold Body of nail (nail plate)
Eponychium
SUMMARY Fingertip injuries are common. Patients will often present to the Emergency Department with a subungual hematoma and a complaint of pain. Rapid relief of pain and good outcomes can be obtained in the majority of cases by simply performing a nail trephination. It is important to distinguish when trephination alone will not be adequate therapy. Patients presenting with nail plate fractures, avulsions of the nail plate, or partial finger amputations will require removal of the nail plate and repair of the nail bed. B
103
Subungual Foreign Body Removal Steven H. Bowman
INTRODUCTION Subungual foreign bodies are often difficult to treat. Foreign bodies such as wood or metal splinters, pencil lead, thorns, spines, or hair may become lodged beneath the fingernail.1–3 Tradesmen such as carpenters, landscapers, auto mechanics, and individuals who work without hand protection with materials that produce small splinters are at risk for this type of injury. Subungual foreign bodies may also present less commonly under the toenails. Patients generally present for medical intervention with pain after unsuccessfully attempting to remove the foreign body. Prior removal attempts often result in breakage of the foreign body or pushing it further beneath the nail; both of which complicate the next extraction attempt. Left untreated, retained subungual foreign bodies often become infected or cause tissue reactions and granuloma formation. These injuries may be treated rapidly with complete removal of the foreign body and without causing additional patient discomfort.
ANATOMY AND PATHOPHYSIOLOGY The distal fingertip and nail apparatus are complex structures (Figure 103-1). The perionychium is composed of the nail bed and the surrounding soft tissue. The hyponychium is the junction of the nail bed at the sterile matrix and the fingertip skin beneath the distal margin of the nail plate. The eponychium is the distal portion of the nail fold where it attaches to the proximal surface of the nail plate. The lunule is the white arc seen on the proximal portion of the nail plate. The nail bed consists of the germinal matrix on the proximal ventral floor of the nail fold and the sterile matrix that extends from the lunule to the hyponychium. The germinal matrix is primarily responsible for the growth of the nail. The subungual space is the area immediately beneath the nail plate. Foreign bodies may enter the subungual space at the distal fingertip beneath the nail, or may penetrate the nail plate directly (Figure 103-2). In either event, separation of the nail from the nail bed results in severe pain. Patients frequently attempt to remove the foreign body immediately because of this intense pain. An infection or foreign body reaction will often ensue if the foreign body is not removed in its entirety.
Root of nail Proximal nail fold
Body of nail (nail plate)
Eponychium Lunule
Nail matrix
Nail bed
Extensor digitorum insertion
Epidermis Flexor digitorum profundus insertion
Distal phalanx
FIGURE 103-1. The anatomy of the distal fingertip and nail bed. A. Surface anatomy. B. Midsagittal view.
INDICATIONS Subungual foreign bodies should be removed to prevent the complications of infection, foreign body reaction, and possible nail deformity. Deeply embedded foreign bodies, splintered foreign bodies, those that traverse the nail plate, or contaminated foreign bodies may require the removal of the nail plate to extract the foreign body. Refer to Chapter 104 regarding the details of removing the nail plate. Consult a Hand Surgeon if the foreign body cannot be removed, if the site is infected, if the foreign body is “chronic”
FIGURE 103-2. Subungual foreign bodies can enter from under the distal nail plate or through the nail plate.
CHAPTER 103: Subungual Foreign Body Removal
and an osteomyelitis is present on radiographs, or if significant injury to the digit is present.
CONTRAINDICATIONS There are no absolute contraindications to the removal of a subungual foreign body.
EQUIPMENT General Supplies • Povidone iodine or chlorhexidine solution • Alcohol swabs • Sterile saline solution • Topical antibiotic ointment • Nonadherent dressing (e.g., petrolatum gauze) • 4 × 4 gauze squares • Adhesive tape Digital/Metacarpal Block • 3 mL syringe • 25 or 27 gauge needle, 1 in. long • 3 to 5 mL local anesthetic solution without epinephrine Scrape Technique • Splinter forceps • #11 or #15 scalpel blade on a handle Wedge Technique • Splinter forceps • Tissue scissors or nail clippers Needle Technique • Needles, 19 and 25 or 27 gauges • Splinter forceps • Hemostat
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breaking or fragmenting the foreign body, and complete removal. Superficially located subungual foreign bodies may be removed by one of the following techniques.
SCRAPE TECHNIQUE This technique has been described anecdotally.4,5 It appears promising as it does not require the administration of a digital block and causes less trauma to the nail and the nail bed compared to other techniques. This technique works well for subungual foreign bodies that either traverse the nail plate or are lodged beneath the distal or middle portion of the nail. Support the patient’s hand on a procedure table. Sit on a chair facing the patient. Place a #11 or #15 scalpel blade on the nail plate and directly over the foreign body (Figure 103-3A). Hold the blade perpendicular to the surface of the nail plate. Draw the scalpel blade from proximal to distal using short strokes and gentle pressure over the foreign body (Figure 103-3A). A small shaving of the nail plate is removed with each stroke of the scalpel blade. The finger may be soaked in lukewarm water for 15 to 20 minutes to soften the nail plate if it is thick and difficult to shave. Continue to remove successive slivers of the nail plate to eventually create a U-shaped defect and expose the foreign body (Figure 103-3B). Grasp the foreign body with a splinter forceps and remove it once a significant portion protrudes. The defect created in the nail plate will move distally and eventually be replaced as the nail plate continues to grow.
WEDGE TECHNIQUE The wedge technique works well for subungual foreign bodies lodged beneath the distal portion of the nail plate.1,6 Patients will require a digital or metacarpal block prior to attempting this technique since it involves manipulation of the nail bed. Sit on a chair facing the patient. Cut a triangular wedge from the distal portion of the nail plate overlying the foreign body with a small pair of tissue scissors or nail clippers (Figure 103-4A).
PATIENT PREPARATION Explain the risks and benefits of the procedure to the patient and/or their representative. Obtain an informed consent for the procedure. Ascertain the patient’s tetanus immune status and administer the appropriate tetanus prophylaxis. The Emergency Physician should attempt to gain the patient’s cooperation. Place the patient sitting or in a semi-recumbent position with their hand on a bedside procedure table. Clean any dirt and debris from the affected finger. Apply povidone iodine or chlorhexidine solution and allow it to dry. Any manipulation of the nail bed will result in additional patient discomfort. Determine the need for a digital or metacarpal block depending on the type and extent of the foreign body and the removal technique. Please refer to Chapter 126 for the complete details regarding anesthesia of the finger or toe. Radiographs are not required unless a metallic foreign body cannot be visually located or the clinical suspicion exists for an osteomyelitis or a gas forming finger infection.
TECHNIQUES Foreign bodies protruding through or from underneath the nail plate may be grasped with a forceps and removed. A scalpel blade or 18 gauge needle may be used to entrap a small protruding tip of the foreign body against the nail plate and draw it out. Do not attempt to remove the foreign body through a puncture wound or small incision. Enlarging the access site allows for easier removal, not
FIGURE 103-3. The scrape technique. A. With the scalpel blade held 90° to the nail bed, strokes are made in a proximal to distal direction. A U-shaped defect will be created to expose the foreign body. B. The foreign body is grasped and removed with a forceps.
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FIGURE 103-4. The wedge technique. A. A triangular incision is made in the nail plate overlying the foreign body. B. The cut section of the nail plate has been removed. The foreign body is grasped with a forceps and removed.
Prevent iatrogenic injury to the nail bed by ensuring that the tip of the scissors under the nail plate is aimed upward and against the nail plate. Remove the wedge of nail. This will provide enough exposure to grasp and remove the foreign body with splinter forceps (Figure 103-4B).
FIGURE 103-5. Needle techniques. A. A 19 gauge needle is inserted along the tract of the foreign body. The tip is used to tease the foreign body out of the tissues. B. The tip of a 25 or 27 gauge needle has been formed into a hook with the aid of a hemostat. The needle is inserted along the tract of the foreign body. The tip is used to grasp the foreign body and pull it out of the tissues.
NEEDLE TECHNIQUES The needle technique works well for subungual foreign bodies located beneath the distal portion of the nail plate.1 Patients will require a digital or metacarpal block prior to attempting this technique. Insertion of a needle into the nail bed is extremely painful. The major drawback of this technique is the potential for leaving fragments of the foreign body beneath the nail plate. Sit in a chair facing the patient. Introduce a 19-gauge needle beneath the nail plate and along the track of the foreign body (Figure 103-5A).7 Use the tip of the needle to touch the foreign body. Lower the hub of the needle to raise its tip and trap the foreign body between it and the nail plate. Withdraw the needle while dragging the foreign body out along the nail plate. Alternatively, tease out and move the foreign body distally until it can be grasped with a splinter forceps. Two alternate techniques have also been described for the needle extraction of a subungual foreign body.7,8 The first is a modification of the needle technique.7 Place a hook in the distal end of a 25 or 27 gauge needle with a hemostat or needle driver (Figure 103-5B). Pass the bent needle along the foreign body tract. Grasp the foreign body with the tip of the bent needle. Withdraw the needle to move the foreign body distally so that it may be grasped with a splinter forceps. A third technique involves the excision of a small portion of the nail plate overlying the foreign body with an 18 gauge needle.8 This is similar to the shave technique with the exception of an 18 gauge needle being used instead of a scalpel blade.
ASSESSMENT The subungual area should be inspected for any remaining fragments of the foreign body that may have broken off in the nail bed. Any remaining fragments of the foreign body must be removed. Refer the patient to a Hand Surgeon if the foreign body fragments cannot be removed.
AFTERCARE In most cases, local wound care and the application of a topical antibiotic are all that is required. Irrigate the foreign body tract and excision site with sterile saline. Apply topical antibiotic ointment to the area. Apply a nonadherent dressing over the nail. Follow-up with a Hand Surgeon and systemic antibiotics may be necessary in severe cases, such as the presence of a nail deformity or chronic foreign bodies with an infection. Postprocedural pain can be managed with acetaminophen or nonsteroidal anti-inflammatory drugs. The use of prophylactic antibiotics is not recommended unless the foreign body was contaminated or had deeply penetrated into the soft tissue of the digit. Instruct the patient to return immediately to the Emergency Department if they develop any signs of an infection (i.e., purulent drainage, increased tenderness, redness or swelling of the digit, or fever).
COMPLICATIONS There are a few potential complications from subungual foreign body removal. Damage to the nail bed can result in a residual nail deformity. Failure to completely remove a subungual foreign body may result in a nail deformity, an infection, or a foreign body reaction with granuloma formation. An infection can result from a contaminated foreign body, flora on the nail plate or skin driven into the soft tissues by the foreign body, or if aseptic technique is not followed.
SUMMARY Patients with subungual foreign bodies often present in severe pain after prior unsuccessful attempts at removal or after complications develop. Though sometimes challenging, it is important that the
CHAPTER 104: Nail Bed Repair
Emergency Physician completely remove the foreign material in the subungual space to prevent further complications. Providing adequate anesthesia and using the appropriate instruments and techniques allows the successful removal of most subungual foreign bodies in the Emergency Department.
697
Dorsal roof
A
Ventral floor (germinal matrix)
Eponychium Nail plate Hyponychium
104
Nail Bed Repair Raemma Paredes Luck and Eric F. Reichman Nail bed (sterile matrix & germinal matrix)
INTRODUCTION The fingertip, the most sensitive area of the hand, is often our first contact with the environment. It has important functional roles in grasping and pinching, in addition to its sensory and cosmetic functions.1,2 The fingernail protects the fingertip and provides increased sensation to the volar pulp.3 However, it also conceals the true extent of fingertip injuries. Hand injuries, with the fingertips most frequently involved, are second only to back injuries as the most common occupational injuries resulting in loss of work days.4 Hence, it is important for the Emergency Physician to evaluate the full extent of the injury, to assess potential disabilities, and to recognize the need for prompt referral to a Hand Surgeon. The fingernails are frequently injured due to their anatomic location and their functional role. Immediate primary repair is the ideal management when these injuries involve the nail bed and surrounding skin fold structures.3,5 Careful repair is necessary to avoid functional impairment and cosmetic derangement of the nail plate.6 The following discussion will refer primarily to the fingernail. The toenail has less importance, both cosmetically and functionally, as grasp and pinch are not needed. However, all the principles and recommendations made also apply to the toenail.7
ANATOMY AND PATHOPHYSIOLOGY Knowledge of the anatomy of the nail unit enables the Emergency Physician to recognize the types of injuries and provide anticipatory guidance of the consequences of these injuries to the patients. The “perionychium” or the nail unit consists of the nail fold, the nail plate, nail bed, and the hyponychium (Figure 104-1).1,2 The nail plate enhances the sensibility of the fingertip by applying a counterforce to the pulp space nerve endings.3 The digital tip and the nail plate also function in unison to smoothly coordinate normal pinch and grasp, which are important for picking up fine objects such as coins and pins.3,8 The nail plate is comprised of compacted, flattened, and elongated anucleated cells that originate from cornified epithelial cells.9 There are three atomic sites where these cells exist.5,8 The nail bed contains two of the sites: the sterile matrix and the germinal matrix.8 The other location is the dorsal roof matrix (Figure 104-1A). Of these, the germinal matrix is the most important for normal nail growth.5 The germinal matrix is responsible for approximately 90% of the nail plate by volume.8 The sterile matrix is responsible for a small percent of the nail plate by volume and varies from individual to individual. This cell production accounts for the nail plate being thicker at its distal tip compared to its proximal origin.8 The nail cells from the dorsal roof matrix are small in number and form a very thin layer on the surface of the nail plate. These cells are responsible for the shine of the nail. If the dorsal roof is destroyed, the nail will lose its shine and become dull.
Distal phalanx
B
Lateral nail fold (perionychium) Lunule Proximal nail fold (eponychium) FIGURE 104-1. Anatomy of the fingernail. A. Lateral view. B. Top view. The colored area represents the perionychium.
Skin overlies the nail plate proximally and laterally (Figure 104-1B).9 The proximal skin fold is referred to as the eponychium. The eponychium protects the germinal matrix located in the proximal nail bed and is the home of the dorsal roof matrix. The skin immediately over the dorsal roof is called the nail wall.8 The lateral skin folds, the adjacent cutaneous areas, and the adjacent nail bed (germinal matrix and sterile matrix) are collectively referred to as the perionychium (Figure 104-1B).6,8,9 The lunule is the pale arc just distal to the eponychium and roughly corresponds to the location of the germinal matrix.1,2,8,9 The nail bed is comprised of the germinal matrix proximally and the sterile matrix distally. The borders of the nail bed are the proximal nail fold, the lateral nail folds, and the hyponychium distally. The hyponychium is the thick layer of cells at the junction of the distal nail bed (sterile matrix) and the fingertip skin.8 It is located just under the distal free margin of the nail plate (Figure 104-1A). The hyponychium serves as a barrier preventing the delicate nail bed from exposure to bacteria and fungi.8 The rate of nail growth varies from finger to finger, from individual to individual, and varies with age.3,8 Nail growth is fastest between 4 and 30 years of age and after 80 years of age. Fingernails grow four times faster than the toenails.1 A new nail takes a minimum of 4 months to grow, and even longer following an injury. Progression of the distal nail occurs at a rate of 0.1 mm/day or 0.5 to 1 mm/week.3,9 This rate varies and is usually faster in fingers than in toes, and faster in the summer months.3 The pressure of new cells being formed leads to the flattening and elongation of the older cells as well as their progression distally.8
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important to note that significant force is required to break, penetrate, or avulse the nail plate.6 Therefore, the fragile nail bed is most likely disrupted if the nail plate is disrupted.
INDICATIONS Injuries to the fingertip and nail, if not initially managed correctly, have long lasting functional as well as cosmetic consequences. The most important consideration is functional.9 Normal nail growth after injury requires a smooth nail bed. Therefore, nail bed injuries must be meticulously repaired to prevent cosmetic deformities and functional impairment.9–11 Scar tissue may form between the wound edges if the nail bed is not accurately approximated. This scar tissue will not form the intermediate nail cells responsible for nail adherence.8 Furthermore, loss of the germinal matrix alone will result in permanent loss of the nail plate.5,12 The skin folds surrounding the nail margins must also be preserved.5,11 Failure to do so will result in the painful complication of adhesion formation between the skin fold and the nail bed.5,11 Secondary repair of these spaces, or of the nail bed, requires more complex procedures and are usually associated with a poor outcome.4,10 Therefore, every effort should be made to primarily repair all significant nail bed injuries. FIGURE 104-2. A crush injury to the distal fingertip. A. Proximal nail bed avulsion. B. A more severe crush injury can result in a proximal nail bed avulsion and fracture of the distal phalanx. Note that the distal nail plate remains attached to the sterile matrix in both of these injuries.
The sterile matrix is more adherent to the nail plate than to the adjacent germinal matrix. Therefore, avulsions involving nail bed tissue are more likely to occur at the sterile matrix.8,10,11 Conversely, the nail plate is loosely held to the germinal matrix. This accounts for the peculiar injury of avulsions of the proximal nail plate from the proximal nail fold while the distal nail plate remains attached (Figure 104-2). The digital artery supplies the volar radial and ulnar sides of the finger and consistently sends even smaller branches to the proximal nail fold and to the nail bed producing a rich capillary network.1 The small veins of the nail bed, pulp, and lateral nail folds coalesce proximally to form a larger commissural vein that runs lateral to the distal phalanx and a terminal vein that runs dorsal to the distal phalanx. The digital nerve accompanies the digital artery and sends branches beyond the distal interphalangeal joint and into the nail fold, nail bed, and the finger pulp. The extensor tendon attaches itself to the distal phalanx just proximal to the germinal matrix.8,11 The periosteum of the distal phalanx, in turn, closely adheres to the sterile matrix.8 With these anatomic considerations in mind, certain patterns emerge as a result of injury. Avulsions of the nail bed tend to occur in the sterile matrix rather than the less adherent germinal matrix. Another pattern of injury seen is the avulsion of the proximal nail plate from the proximal nail fold while the distal part remains attached to the nail bed (Figure 104-2). Because the sterile matrix closely adheres to the periosteum of the distal phalanx, fractures of the distal phalanx might injure the nail bed producing a subungual hematoma.6 Due to the close proximity of the germinal matrix and the attachment of the extensor tendon, injuries to or repair of these structures might involve the other. A subungual hematoma is a collection of blood between the nail bed and the nail plate. Although a large subungual hematoma may require repair of the underlying nail bed, this is controversial. Emergency Physicians must consider in each case whether there exists enough damage to require surgical nail bed repair. It is
CONTRAINDICATION No absolute contraindications exist for primary nail bed repair. Any life-threatening injuries, limb-threatening injuries, and/or uncontrolled hemorrhage must be addressed prior to nail bed repair.
EQUIPMENT • • • • • • • • • • • • • • • • • • • •
Povidone iodine or chlorhexidine solution Restraining device(s), as necessary 10 mL syringe armed with a 27 gauge needle Local anesthetic solution without epinephrine, 1% lidocaine or 0.25% bupivacaine Digital tourniquet #15 scalpel blade on a handle Magnification device Sterile prefabricated nail, if available Nonadherent petrolatum gauze 5-0, 6-0, and 7-0 chromic gut (or polyglactin 910 or irradiated polyglactin 910) on a p-3 cutting needle 6-0 monofilament nylon sutures Needle driver Curved hemostat Fine scissors or periosteal elevator Forceps Sterile towels or drapes Sterile gloves Dry gauze/tube gauze Splinting material Battery-powered electrocautery device
The use of a digital tourniquet is essential to properly repair a nail bed. Its use provides a bloodless field, which allows for a more meticulous and precise wound approximation. Numerous options are available to use as a tourniquet in the Emergency Department. Home-grown options include the use of a sterile Penrose drain,
CHAPTER 104: Nail Bed Repair
FIGURE 104-3. A sterile Penrose drain or IV tourniquet used as a digital tourniquet.
699
FIGURE 104-5. The Tourni-cot digital tourniquet.
rubber IV tourniquet, or sterile glove. A sterile Penrose drain or IV tourniquet secured with a hemostat is often used as these items are readily available (Figure 104-3). A sterile glove may be used as a tourniquet (Figure 104-4). Apply a sterile glove onto the patient’s hand that is snug or a size one-half smaller than their actual glove size. Cut just the tip off of the glove over the affected finger(s). Roll the cut finger back and onto the proximal phalanx to form the tourniquet (Figure 104-4). Several commercially produced digital tourniquets are often available in the Emergency Department. The Tourni-cot (Mar Med Co., Grand Rapids, MI) is a sterile, single use, disposable, rubber ring that slides over the fingertip and rolled backward until it rests over the proximal phalanx (Figure 104-5). These come in several sizes to fit the appropriate finger size. The advantage of the Tourni-cot is that it exsanguinates the digit as it is applied. The T-Ring (Precision Medical Devices LLC, San Clemente, CA) is a “one size fits all” digital tourniquet (Figure 104-6). It is a sterile, single use, disposable, rubber diaphragm with a central hole. It slides over the fingertip and is pushed backward until it rests over the proximal phalanx. The T-Ring also exsanguinates the digit as it is applied.
The first step in the evaluation of fingertip injuries is obtaining a thorough history. The mechanism of injury can provide some clues to the type and extent of injuries as well as amount of contamination to be expected. Other pertinent information includes age, hand dominance, occupation or hobbies, comorbidities, and tetanus vaccination status. All significant injuries to the fingertip should be evaluated radiographically for fractures. The management of fingertip injuries may differ in the presence of a fracture. Thoroughly evaluate and document a complete neurovascular examination, tendon function and intactness, and ligamentous stability of the joints. Ascertain the patient’s tetanus immune status and administer prophylaxis if required. It is important to explain both the risks of doing the procedure and of not doing the procedure. Document this conversation and obtain an informed consent. Place the patient on a gurney with the hand on a bedside procedure table in a well-lit area. Be prepared to use age-appropriate sedation or to apply appropriate restraints for children.11 Procedural sedation may be necessary in patients who are agitated, uncooperative, or require extensive repair. Apply a type
FIGURE 104-4. A sterile glove used as a digital tourniquet.
FIGURE 104-6. The T-Ring digital tourniquet.
PATIENT PREPARATION
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of magnification device if available. This may consist of a head-strap device, a swing arm device, magnification glasses, or loupe magnification glasses. Anesthetize the injured digit(s). Anesthesia may be achieved with a digital block or a metacarpal block when only a single digit is involved.6 Lidocaine (1% or 2%) can provide pain relief of up to 3 hours. For longer analgesia, use 0.5% bupivacaine. Although recent studies have shown that the practice of using lidocaine with epinephrine for digital blocks is safe, this is still controversial and many do not advocate its use.13–15 Multiple metacarpal blocks or an axillary nerve block may be performed if multiple digits are involved.6 Please refer to Chapter 126 for the details regarding regional nerve blocks. Thoroughly clean the hand of any dirt and debris. Apply povidone iodine or chlorhexidine solution and allow it to dry.16 Irrigate the wound with sterile saline. If the nail plate has been avulsed, irrigate it with a dilute povidone iodine or chlorhexidine solution followed by a gentle rinse with sterile saline. It is important not to scrub the undersurface of the avulsed nail plate because adherent squamous tissue may be destroyed.6 A bloodless field is desired and, in many cases, necessary. Apply a digital tourniquet as described in the “Equipment” section above.6 If available, a pneumatic tourniquet may be placed on the arm instead of using the digital tourniquet. The pneumatic tourniquet is especially helpful when the patient has fractures or lacerations of the proximal digit that preclude the use of a digital tourniquet. Avoid using a blood pressure cuff, as these tend to deflate during use. As with all tourniquets, limit the amount of time in which the tourniquet is in place. Create a sterile field by applying sterile towels.
TECHNIQUES Adhering to certain principles will improve the outcome when repairing nail beds. A smooth and flat nail bed is necessary to the normal growth of the nail and should be the primary goal in any repair. Avoid or severely limit the amount of debridement.5 The germinal matrix must be meticulously repaired and the proximal nail fold, the eponychium, preserved or that space is obliterated within a few days and result in adhesions or abnormal nail growth.5 Thoroughly clean and replace the nail plate whenever possible. This will preserve the nail folds surrounding the nail bed, allow the nail plate to serve as a splint for fractures, and act as a protective cover for the healing nail bed.6 Treatment goals also include preservation of length and sensation of the fingertip, early mobilization, prevention of joint contractures, and attention to cosmesis.4,17 The technique of nail bed repair depends upon the type of injury as well as which structures are involved. Various classification schemes, such as the nature of injury or anatomic location, have been developed to categorize fingertip injuries and guide treatment. Nail bed injuries are classified as simple lacerations, crushing lacerations, avulsion-lacerations, lacerations with associated fractures, lacerations with loss of skin and pulp, and fingertip amputations.2,12
FIGURE 104-7. Removal of the nail plate. Dissect along the plane between the nail plate and the nail bed using a pair of fine scissors or periosteal elevator.
scissors parallel to the long axis of the finger. Slightly angle the tips of the scissors toward the nail plate to prevent any damage to the nail bed.11 Advance the tips of the scissors 1 to 2 mm. Open the blades of the scissors to separate the nail bed from the nail plate. Close the blades of the scissors. Continue to advance the tips of the scissors in 1 to 2 mm increments and separate the nail bed from the nail plate. Stop advancing the scissors when the tips of the blades are at the level of the eponychium. Firmly grasp the nail plate with a hemostat. Pull the nail plate parallel to the long axis of the finger to completely remove it from the finger. Making two linear incisions with a scalpel at 90° from the eponychial edge will allow greater exposure to the germinal matrix for repair (Figure 104-8).7 This allows the eponychium to be folded or sutured back and therefore increase exposure of the germinal matrix.2,17
SIMPLE LACERATIONS Simple lacerations are caused by localized blows to the nail plate. After removing the nail plate and exposing the nail bed, repair the laceration meticulously using 6-0 or 7-0 chromic gut or irradiated polyglactin 910 sutures.2,6,17 Minimize debridement as much as possible to avoid scarring that will result in nonadherence or
NAIL PLATE REMOVAL A significant force is required to break the nail plate. The nail plate should be removed to visualize the underlying nail bed if the nail plate is damaged or avulsed, or the lateral skin folds lacerated as an associated nail bed injury is highly likely. Removal of the nail plate is unnecessary in minor injuries where the nail plate is not damaged and still attached to the nail folds. Remove the nail plate to repair nail bed injuries or to inspect the nail bed for potential injuries (Figure 104-7). Insert the closed tips of a fine scissors between the nail bed and the nail plate. A periosteal elevator, if available, can be substituted for the scissors. Hold the
FIGURE 104-8. Incisions can be made at 90° to the corners of the eponychium for better exposure of the germinal matrix.
CHAPTER 104: Nail Bed Repair
FIGURE 104-9. Crushing lacerations to the nail bed. A. Stellate or complex lacerations of the nail bed can occur after a crush injury. B. Approximation of the nail bed with fine absorbable sutures.
splitting of the nail plate. Repair any skin lacerations adjacent to the nail bed using 6-0 or 5-0 monofilament nylon sutures.5 Nail fold lacerations may require repair in layers in order to preserve these spaces.9
CRUSHING LACERATIONS The second type of injury is a crush injury with resultant lacerations. Crushing injuries may produce stellate lacerations and fragmentation of the nail bed (Figure 104-9A). Attempt to meticulously repair the fragmented nail bed using 6-0 or 7-0 chromic gut or irradiated polyglactin 910 sutures to achieve precise approximation and the smoothest result possible (Figure 104-9B).6
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previously described injuries. Distal nail bed avulsions simply require petrolatum gauze to be placed over the injury followed by sterile gauze. Suture the petrolatum gauze and sterile gauze in place using 5-0 or 6-0 nylon suture for 10 days to allow the wound to heal by second intention (Figure 104-10B).5,17 Avulsion-laceration injuries may require consultation with a Hand Surgeon depending on the amount of tissue involved and whether the germinal matrix is involved.6,11,12 More severely damaged nail beds with a large amount of avulsed tissue usually require dermal grafts or split-thickness matrix grafts.6 Small fragments of avulsed nail bed may remain attached to the nail plate. These may be simply treated by carefully replacing the nail plate in its anatomic position.18 Larger segments of avulsed nail bed that remain attached to the nail plate should be repaired (Figures 104-11A & B). Gently shave away the nail bed from the nail plate with a #15 scalpel blade (Figure 104-11C). Replace the avulsed nail bed and suture it in place with 5-0 or 6-0 chromic gut or irradiated polyglactin 910 sutures (Figure 104-11D).10,18 Apply a petrolatum gauze dressing and replace the nail plate. A special type of avulsion injury occurs when there is a crush injury to the distal fingernail. This results in an avulsion of the proximal nail plate with or without involvement of the germinal matrix (Figure 104-2). The proximal nail plate is less adherent to the nail bed and can be pulled out from under the eponychium (Figure 104-2). Remove the nail plate if the proximal nail plate is avulsed without involvement of the germinal matrix. Clean the nail plate and nail bed with sterile saline. Replace and secure the nail plate.
AVULSION-LACERATIONS The third type of nail bed injury is the avulsion-laceration (Figure 104-10A). These injuries are more complex than the
FIGURE 104-10. Avulsion-laceration of the nail bed. A. The dorsal aspect of the fingertip is avulsed with the nail plate. B. Petrolatum gauze is placed over the injury. This is subsequently covered with sterile gauze and sutured into place for 10 days.
FIGURE 104-11. Large avulsion of the nail bed that is adherent to the nail plate. A. Lateral view of injury. B. Top view of injury. C. Gently shave away the avulsed segment. D. Repair the nail bed using the avulsed segment.
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FIGURE 104-13. Classification of fingertip injuries. Zone I is distal to the bony phalanx. Zone II is distal to the lunule and over the bony phalanx. Zone III is proximal to the distal end of the lunule.
FIGURE 104-12. Repair of the germinal matrix after an avulsion. A. A series of horizontal mattress sutures are placed. B. The nail bed is returned to its proper location and the sutures tied. C. Lateral view of the repair.
bony phalanx. These injuries often have exposed bone. Zone III injuries occur proximal to the distal end of the lunule. Zone II and Zone III injuries should be managed in consultation with a Hand Surgeon. Either type of injury may require reconstruction with a pedicle flap and/or skin grafting.3
More often with these crush injuries the germinal matrix is avulsed as well. In these cases, the germinal matrix should be replaced with a series, usually three, of 6-0 nylon simple interrupted or horizontal mattress sutures (Figure 104-12).5,6,10 Place all three sutures before returning the nail bed to its proper location. Making two linear incisions with a scalpel at 90° from the eponychial edge will allow exposure to the germinal matrix for repair (Figure 104-8).7 This allows the eponychium to be folded or sutured back and therefore increase exposure of the germinal matrix. Place a piece of petrolatum gauze between the eponychium and the germinal matrix after the repair (Figure 104-12B). Larger germinal matrix avulsions require consultation with a Hand Surgeon for grafting.2,6,11,17
TREPHINATION FOR A SUBUNGUAL HEMATOMA
LACERATIONS WITH ASSOCIATED FRACTURES The fourth type of nail bed injury is lacerations associated with fracture(s). Approximately 50% of nail bed injuries have an associated phalangeal tuft fracture.19 The nail bed laceration should be repaired as previously described and the fracture addressed as a separate entity.5 It is important to remember that the sterile matrix is closely adherent to the dorsal periosteum of the distal phalanx. Therefore, fractures require precise anatomic reduction in order for normal nail bed healing and nail plate growth to take place.6,10,12 Replacing the nail plate and splinting the finger after repairing the nail bed laceration is often enough to reduce these fractures. Occasionally, fixation may be employed by a Hand Surgeon using Kirschner wires to prevent rotation of the bony fragments.2,6
LACERATIONS WITH SKIN LOSS AND FINGERTIP AMPUTATIONS The final two types of injury are lacerations with loss of skin and pulp, and fingertip amputations. They can be further classified according to zones based upon the anatomic level of amputation (Figure 104-13).3 Zone I injuries occur distal to the bony phalanx. These do not result in the loss of function and rarely result in a cosmetic deformity. Management consists of cleansing, placing topical antibiotic ointment over the injured area, and then applying a layer of petrolatum gauze. This should be followed by a sterile dressing and a splint. Zone II injuries occur distal to the lunule and over the
A subungual hematoma is a collection of blood under the nail plate caused by blunt trauma to the fingertip. The nail bed is usually crushed or lacerated with resultant extravasation of blood into the plane between the nail plate and the nail bed.11 As pressure builds up, compression of nail bed nerves occurs and often causes significant pain. Usually this pain is what causes the patient to seek medical attention. The management of subungual hematomas is discussed separately because these injuries are typically minor and treated by simple trephination. A complete discussion of the management of subungual hematomas can be found in Chapter 102. It is generally accepted that subungual hematomas 50% of the nail plate. The concern is that a larger hematoma may hide an occult laceration that requires repair in order to avoid the complication of step-off with subsequent ridging as the new nail grows back. Some authors feel that it is impossible to accurately assess the amount of damage beneath a subungual hematoma unless the nail plate is removed to directly inspect the nail bed.6,21 These authors noted that subungual hematomas that have separated greater than 50% usually have lacerations that require repair. Another study found that a subungual hematoma with more than 50% separation had a 60% incidence of having a nail bed laceration that required repair and up to a 95% incidence when there was an associated phalanx fracture.21 In contrast to these studies, a prospective study found no complications at 6 months follow-up for subungual hematomas treated by electrocautery trephination alone.2,20 This was regardless of the size of the subungual hematoma or the presence of a fracture. These authors feel that removing the nail plate and attempting repair may actually cause further trauma to the nail bed.20
CHAPTER 104: Nail Bed Repair
FIGURE 104-14. A hole is placed in the nail plate before it is sutured in place.
It was previously recommended that radiographs be obtained to rule out a fracture for all hematomas larger than 50% of the nail plate. A newer study found no correlation between the size of the hematoma and the presence of fractures.20 If a fracture is suspected, have a low threshold to obtain plain radiographs prior to evacuating the hematoma. In summary, most subungual hematomas may be treated by simple nail trephination using an electrocautery device. This procedure will lead to beneficial drainage only if done before 36 to 48 hours from the time of the injury.11 The clinical benefit of nail bed repair with larger subungual hematomas is controversial. It may be prudent to maintain a lower threshold for nail bed repair with a larger subungual hematoma, particularly if an ideal cosmetic outcome is desired.
AFTERCARE Whenever possible, the nail plate should be replaced after repairing any of the above-mentioned injuries. The nail plate covers the sensitive nail bed and protects it from injury, maintains the proximal nail fold (eponychium) to allow for growth of a new nail, and splints the nail bed. In order to accomplish the best outcome, place a hole in the center of the nail plate to allow for fluid drainage.11 Make one or two holes in the lateral aspects of the nail plate. Suture the nail plate in place using 5-0 nylon sutures through the lateral skin folds (Figure 104-14).6,10,11 These sutures should remain in place for 7 days. An alternative to suturing the nail plate in position is to use tissue adhesive. After replacing the nail plate, apply tissue adhesive along the eponychium and lateral nail folds at the area where they overlap the nail plate. An artificial nail may be used if the original nail plate is not available. The potential problem with sterile prefabricated nails is that there exists an increased risk for infection and a risk of erosion into the nail bed or nail folds.6 The editor recommends petrolatum gauze be used to maintain the nail
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fold structures when the original nail plate is not available or significantly damaged (Figure 104-15). After repair of the nail bed, the digit(s) involved will need to be bandaged in order to protect it from infection, moisture, and trauma. The application of becaplermin, recombinant human platelet-derived growth factor, has shown to improve outcomes.22 This substance is not routinely used in the Emergency Department and should be applied after consultation with a Hand Surgeon. Place petrolatum gauze over the nail bed to avoid adherence from secretions. Apply a tube gauze dressing followed by a digital aluminum splint.3 Movement of the distal interphalangeal joint should be restricted for 7 to 10 days with a splint.6 For infants and young children, the entire hand should be dressed. If petrolatum gauze was used to keep the proximal nail fold (eponychium) open, it should be removed in 5 to 10 days.6 Petrolatum gauze used to keep open the lateral nail folds (perionychium) should remain in place for 10 days.5 Any sutures placed in the skin structures or nail folds should be removed in 7 to 10 days.5 Prophylactic antibiotics are not routinely required. They are recommended for large avulsions, amputations, and associated fractures when there is contamination with organic material.6 Topical antibiotics may be applied to Zone I fingertip amputations. All injuries require a wound check in 24 to 72 hours.3,5,6 The patient’s tetanus immune status should be determined and prophylaxis administered if required. The hand should be elevated whenever possible. Narcotic analgesics may be prescribed as needed for pain control. It is important to explain to the patient that regeneration of a new nail may take up to 6 to 12 months.6 Warn the patient that as the new nail forms, it may look irregular and snag on cloth or string objects.6 The patient should trim and file the leading edge of the new nail once it extends past the hyponychium in order to avoid snagging.
COMPLICATIONS The complications associated with failure to repair or improper repair of a nail bed can be either functional, cosmetic, or both. The more serious complications are those which impair function or cause pain. There are basically seven complications that may arise. These exclude the infectious complications (abscess formation, cellulitis, and lymphangitis) that are inherent to all wounds. The occurrence of osteomyelitis from these injuries is rare, even with open fractures. The seven complications are loss of the nail, a split nail, a nonadherent nail, an ingrown nail, a malaligned nail, wide nails, and narrow nails.12 The complete loss of a nail could result in significant functional impairment to the fingertip as well as an abnormal looking fingertip. Complete nail loss occurs when there is complete disruption of the germinal matrix, either by significant avulsion of the matrix or amputation. Remember that if the germinal or roof matrices are not
FIGURE 104-15. Petrolatum gauze may be placed between the dorsal roof and germinal matrix (A) or between the lateral skin fold and nail bed (B) to preserve the skin fold spaces.
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SECTION 7: Skin and Soft Tissue Procedures
repaired, the pouch deep to the proximal skin fold (eponychium) is obliterated within a few days.20 A split nail occurs when the germinal matrix is improperly approximated.5,6,12 A wide scar will result that will not form a new nail. Subsequently, a split nail develops. This can be avoided by the careful approximation of the nail bed with sutures. A nonadherent nail occurs when the nail bed is not repaired and granulation tissue forms secondarily. The nail plate will not adhere at the site of the granulation tissue as well as distal to the granulation tissue.12 The nail can snag and be exposed to repeated tears once the nail plate loses adhesion to the nail bed. The nail plate may ingrow if the lateral skin folds or sulci are not maintained and kept open.12 Adhesions that form between the skin and nail bed can be very painful when the new nail tries to grow through that space.5 Ingrown nails also have the long-term problem of a higher rate of infections (paronychia). This can be avoided by the replacement of the nail plate or the placement of petrolatum gauze to elevate the lateral nail fold from the nail bed. The nail plate will grow in a malaligned direction if the matrix is displaced or repaired in such a manner that it is improperly aligned.12 Functional impairment and cosmetic deformity may ensue depending upon the degree of this misdirected growth. Wide nails often result from a crush injury with a tuft fracture.12 Separated bony fragments leave the nail bed flatter and wider. Narrow nails occur when a central avulsion-laceration is not repaired. Scar tissue forms in the center and allows the intact lateral portions to contract toward each other.12 The new nail subsequently becomes narrow and thick. Tubular gauze dressings are commonly applied after the repair of a nail bed. When improperly placed, tubular gauze dressings can result in significant injury.23,24 This includes digital ischemia that may be permanent and require an amputation. Tubular gauze dressings should not be placed by healthcare personnel not trained in their proper application.
SUMMARY Nail bed injuries are common and may result in a cosmetically deformed or functionally impaired fingertip. Complications may occur even with precise repair. The treatment of choice is immediate primary repair of the nail bed and surrounding structures. Remember to minimize any debridement and to replace the nail plate whenever possible. Injuries with associated fractures and simple subungual hematomas are managed separately from the nail bed injury. Always be thorough and meticulous when repairing nail bed injuries to provide the best possible outcome. Finally, know when to consult with a Hand Surgeon.
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often give a history of repetitive motion at the site. The mass usually increases in size progressively over time or, occasionally, may grow rapidly over a short period. Patients presenting to the Emergency Department with ganglia may have already attempted one of several popular home remedies, including homeopathic medications or striking the cyst firmly with a large book or hammer. Ganglion cyst aspiration is a relatively simple procedure that may be performed by the Emergency Physician. The practice of cyst aspiration has been challenged because of the high recurrence rate after the procedure.2,3 Recurrence rates of up to and even greater than 50% have been described.4,5 However, the procedure usually alleviates presenting symptoms, is occasionally curative, and is more cost-effective than referring all patients for surgical treatment.6
ANATOMY AND PATHOPHYSIOLOGY Ganglia are synovial cysts that originate from a joint capsule or tendon sheath. They have no malignant potential. It is unclear whether ganglia are formed by herniation of the tendon sheath, myxomatous degeneration of connective tissue, or some other mechanism. Contained within the cyst is a viscous, jelly-like fluid. Ganglia often connect with the underlying synovial cavity or tendon sheath by a stalk. Hyaluronic acid makes up all or part of the mucoid fluid.7 Ganglia are usually encountered on the dorsum of the wrist, in particular over the scapholunate ligament (Figure 105-1). They may also be found on the palmar surface of the wrist, the lateral surface of the wrist, or on the hand itself. Ganglia of the foot and ankle are less commonly seen.8 Ganglia are less commonly encountered in other areas such as the shoulder, hip, elbow, knee (including the anterior cruciate ligament), the lumbar spine, temporomandibular joint, and even the odontoid process of the cervical spine.9–11 Ganglia present as fixed or slightly movable masses that are usually solitary. Frequently characterized as smooth and “rubbery,” cysts may become more noticeable with wrist flexion. They vary in size from barely palpable to 3 cm in diameter (smaller than 1.5 cm being the norm). Tenderness is sometimes but not invariably present. Ganglion cysts will transilluminate, as they are fluid-filled. They may “disappear” over time by spontaneously rupturing or resorption. Diagnosing a ganglion cyst is usually not difficult. However, ganglia of the foot and those occurring in other uncommon locations may be difficult to palpate despite causing significant discomfort. The differential diagnosis of ganglia includes joint capsulitis, neuromas, and other soft tissue neoplasms such as sarcomas and chondrosarcomas. Ultrasonography can be employed to aid in the diagnosis, particularly of occult ganglia or ganglia presenting atypically.12 MRI is frequently used to confirm the diagnosis and plan its
Ganglion Cyst Aspiration and Injection Thomas P. Graham
INTRODUCTION Ganglion cysts, also known as synovial cysts or ganglia, are the most common soft tissue tumors of the wrist and hand.1 They are a common reason for patients to present to the Emergency Department. The chief complaint is usually a mild pain or ache, exacerbated by movement, and localized to a 1 to 2 cm mass on the wrist or hand. Patients may also present with concerns about a painless “lump.” Acute trauma prior to presentation is uncommon, though patients
FIGURE 105-1. Oblique view of the wrist demonstrating a ganglion cyst overlying the scapholunate joint.
CHAPTER 105: Ganglion Cyst Aspiration and Injection
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operative removal. Plain radiographs and laboratory tests are not helpful in the work-up.
INDICATIONS The most common indication for ganglion aspiration is worsening pain and swelling, in particular when normal range of motion is restricted or occupational disability is present. Failure of conservative measures such as rest, splinting, and the use of nonsteroidal anti-inflammatory medications to resolve symptoms may also prompt ganglion aspiration in the Emergency Department.
CONTRAINDICATIONS There are few contraindications to ganglion cyst aspiration. Introducing a needle through an area of cellulitis should be avoided. However, cellulitis overlying a ganglion is uncommon and should raise suspicion for an alternate diagnosis such as a skin abscess. The procedure can be safely deferred, with the patient being given a referral to a Hand Surgeon, if the diagnosis of a ganglion is uncertain. The location of a ganglion is generally not a contraindication to aspiration. However, the procedure should be deferred if there is a concern that the aspirating needle could damage an adjacent structure and cause neurologic or vascular injury. Aspiration of lower extremity ganglia may be performed in a similar fashion to hand and wrist lesions, with similar results.8,13 Some literature suggests that volar wrist ganglion cysts recur at an even higher rate than those of the dorsal wrist and lower extremity; leading some authors to recommend surgical excision, and not aspiration, as the primary therapy for this subset of ganglia.14
EQUIPMENT • • • • • •
Sterile gloves Povidone iodine solution or chlorhexidine solution Local anesthetic solution without epinephrine 25 or 27 gauge needle on a 3 mL syringe for local anesthesia 16 or 18 gauge needle on a 5 or 10 mL syringe for aspiration 10 to 15 mg methylprednisolone acetate (20 mg/mL) or prednisolone tebutate (20 mg/mL)
PATIENT PREPARATION Explain the risks and benefits of the procedure to the patient and/or their representative. Obtain an informed consent, either signed or verbal, with adequate documentation to support the latter method. If available, ultrasonography can be used to confirm the diagnosis and to facilitate needle entry into the cyst. When ganglia are located near neurovascular structures, ultrasound can help to avoid these structures.15 Place the patient on a gurney with the hand on a bedside procedure table. Clean the skin of any dirt and debris. Apply povidone iodine or chlorhexidine solution and allow it to dry. It is recommended to provide local anesthesia for patient comfort, although the cyst can be aspirated and/or injected without anesthesia. Place a subcutaneous wheal of local anesthetic solution immediately over or adjacent to the periphery of the ganglion.
TECHNIQUE GANGLION ASPIRATION Manipulate the wrist (or other affected extremity) to expose more of the cyst and facilitate needle entry into the cavity. Insert a 16 or 18 gauge needle on a 5 or 10 mL syringe through the anesthetized tissue and into the ganglion cyst cavity (Figure 105-2). Apply negative
FIGURE 105-2. Cross section through the scapholunate joint demonstrating a ganglion cyst. The needle is inserted into the cyst cavity to aspirate its contents.
pressure to the syringe to aspirate the cyst contents once the tip of the needle is within the cyst cavity. The contents may be difficult to aspirate, as the mucinous contents of the cyst are quite viscous. The cyst can be manipulated and compressed to express more of the contents into the syringe once the very viscous, clear or yellow material begins to flow into the syringe. Generally, 1 to 2 mL of fluid can be aspirated from a typical ganglion. Withdraw the needle when fluid can no longer be aspirated. Apply a simple dressing. A pressure dressing may also be temporarily applied, taking care not to compromise neurologic or vascular function.
GLUCOCORTICOID INJECTION The injection of glucocorticoids into a ganglion cyst immediately after aspiration is commonly recommended. One small study showed glucocorticoid injections decreased recurrence rates compared to aspiration alone.16 The literature has not yet shown a clear benefit.17 If a steroid injection is desired, securely hold the aspirating needle in place after the cyst contents have been aspirated into the syringe. Remove the syringe. Without moving the needle, attach a second syringe containing 10 to 15 mg of the glucocorticoid solution onto the needle. Aspirate to confirm the tip of the needle is not within a vascular structure. Inject the glucocorticoid solution into the cyst cavity. Withdraw the needle and apply a simple dressing.
ALTERNATIVE TECHNIQUES Other variations of ganglion cyst aspiration and injection have been described in the literature. The injection of hyaluronidase into the cyst, with or without corticosteroids, has shown favorable results.18,19 Puncturing the ganglion wall at multiple separate locations has not been proven to decrease the recurrence rate when compared to aspiration at a single point alone.20 Injection of hypertonic saline and other sclerosants (e.g., 1 mL of 3% sodium tetradecyl sulfate) has been suggested. Further study is necessary before these techniques can be recommended for widespread use in the Emergency Department.
ASSESSMENT Patients usually report total or near-total relief of their symptoms immediately after aspiration. Obtaining highly viscous, clear or yellow fluid from the cyst virtually confirms the diagnosis.
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Obtaining purulent fluid suggests a skin abscess and not a ganglion cyst. Failure to obtain fluid does not rule out the diagnosis of a ganglion, but should prompt an evaluation for alternative diagnoses.
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Subcutaneous Abscess Incision and Drainage Samuel J. Gutman and Michael B. Secter
AFTERCARE Patients should be reassured that ganglia are not malignant tumors. Immobilization of the affected limb may be performed temporarily for patient comfort. However, splinting limits the ability of patients to function normally and does not appear to affect recurrence rates.21 Aftercare instructions should direct patients to return to the Emergency Department for any significant increase in pain, erythema at the site or up the extremity, swelling beyond the ganglion’s original size, purulent discharge, continued bleeding, or the development of a fever. Patients should also be directed to elevate the extremity, avoid strenuous activity of the affected limb, and rewrap the pressure dressing (if one is applied) to make it snug but not uncomfortable. Acetaminophen or nonsteroidal anti-inflammatory medications may be recommended for relief of mild postprocedure pain. Narcotic analgesics are not required nor recommended. Oral corticosteroids have not been demonstrated to play a role in ganglion therapy. All patients with ganglion cysts aspirated in the Emergency Department should be informed of the potential for recurrence and the possibility of definitive ganglion treatment by surgical excision. Referral to a Hand Surgeon should be provided, if desired by the patient. Although reports of postsurgical recurrence rates vary widely, currently the most effective therapy for ganglion cysts is believed to be open excision. During this procedure, a Hand Surgeon removes the cyst and, if possible, the stalk or pedicle that connects it to the normal synovium. Arthroscopic removal of wrist ganglia has also been described and performed successfully.22
COMPLICATIONS Complications of ganglion cyst aspiration are uncommon. They include bleeding and infection. Bleeding is self-limited and easily controlled with manual pressure. The use of sterile technique will minimize any infectious complications (abscess, cellulitis, or septic arthritis). Rare complications of corticosteroid injection include localized depigmentation that is due to injection outside of the cyst capsule or leakage out of the cyst capsule through the needle tract.23 Subcutaneous infiltration of glucocorticoids can also result in fat atrophy, skin atrophy, and skin dimpling from fat atrophy.
SUMMARY Ganglion cysts are common growths of the wrist and hand. They frequently enlarge to cause pain, sometimes to the point of disability. Contraindications to the aspiration of a ganglion cyst in the Emergency Department are few. The procedure is often warranted due to debilitating pain, deformity, or inability on the patient’s part to promptly seek the care of a surgical specialist. The procedure is simple, quick, and only slightly uncomfortable if performed correctly. Although the injection of steroids into the cyst is commonly advocated to prevent recurrence, the efficacy of this procedure has not been conclusively demonstrated. Ganglia recurrence is very common after aspiration and may occur even after surgical excision. This fact must be clearly relayed to the patient. All patients should be offered referral to a Hand Surgeon on a nonemergent basis to discuss further intervention.
INTRODUCTION Subcutaneous abscesses are commonly seen in the Emergency Department. Approximately 1% to 2.5% of patients present with this chief complaint.1–3 Abscesses occur in numerous anatomical areas with varied etiology and bacteriology. An abscess is a tender and fluctuant mass located in the dermal or subdermal tissue. It usually demonstrates the classic inflammatory responses of rubor, tumor, dolor, and calor. Although the abscess is usually tender, the surrounding and underlying tissue should not be tender.4,5 There is usually minimal surrounding erythema in a mature abscess. Incision and drainage is the definitive treatment of a soft tissue abscess.6 This procedure results in significant improvement in symptoms and a rapid resolution of the infection in uncomplicated cases.7 However, premature incision before localization of pus will not be curative and may be deleterious. In cases of immature abscesses or cellulitis, oral antibiotics and warm compresses may be of value in helping the infection to coalesce. These methods are not a substitute for incision and drainage and should not be continued for more than 24 to 36 hours without a reassessment of the patient. With the emergence of methicillin-resistant Staphylococcus aureus (MRSA), the role for ancillary antibiotic use has come into question.
ANATOMY AND PATHOPHYSIOLOGY PATHOGENESIS An abscess is a localized collection of pus caused by suppuration buried in a tissue, organ, or confined space.8 Intact skin is very resistant to bacterial invasion. Localized pyogenic infections are usually initiated by a breakdown in the normal epithelial defense mechanisms in the normal host. Plugging of the ducts of a superficial exocrine gland, such as apocrine and sebaceous glands or a congenital cyst or sinus, may initiate the process. Occlusion prevents desquamation and provides a moist environment for organisms to proliferate. The combination of a high concentration of organisms, the presence of nutrients, and sufficient damage to the corneal skin layer to allow organisms to penetrate the skin defenses results in abscess formation.1,9 Subcutaneous abscesses typically begin as a cellulitis with organisms that cause necrosis, liquefaction, and accumulation of leukocytes and debris. Early stages appear as an area of hyperemia and tender inflammation that later becomes fluctuant as an exudate of leukocytes, necrotic material, and cellular debris accumulates. This is followed by loculation and walling off of the pus. This progresses and the area of liquefaction increases until it “points” and eventually ruptures through the area of least resistance.5 The body area involved depends upon host factors such as drug use, employment-related exposures, or minor trauma.9,10 Areas with a compromised blood supply are more prone to infection as normal host cell-mediated immunity is not as available.9 The frequency of abscess occurrence in different body areas includes the buttocks and perirectal area in 25% of cases, the head and neck in 20%, the extremities in 18%, the axilla in 16%, and the inguinal area in 15%.1
BACTERIOLOGY The majority of abscesses are polymicrobial with the isolated organisms usually representing the normal resident flora associated with
CHAPTER 106: Subcutaneous Abscess Incision and Drainage
the body area on which the abscess is found.1,11 Nonresident bacteria are found in abscesses that occur as a result of direct inoculation of extraneous organisms such as those following human bite wounds, intravenous drug use, or bacterial seeding of embedded foreign bodies.12 In normal hosts, aerobic Staphylococcus and group A Streptococcus are the most common organisms isolated from abscesses of the head, neck, extremities, and trunk.11,13 Anaerobes are found in all areas of the body but predominate in abscesses of the buttocks and perirectal regions.11,13 Staphylococcus aureus occurs in 24% to 60% of abscesses and in pure cultures is the only organism in 21% to 72% of cases.1,13–16 Community-acquired MRSA (CA-MRSA) is presently considered to be the most common identifiable pathogen causing abscess at major centers.17 CA-MRSA is defined as infection with MRSA acquired in the community lacking the traditional risk factors of hospital-acquired MRSA including a recent stay in a long-term care facility or in a day care setting, recent healthcare contacts or surgery, an indwelling device, dialysis, immunosuppression, chronic illness, or recent antibiotic use.18,19 Many cohorts of patients who are at a higher risk of acquiring MRSA infections include those with recent household or daycare contacts, children, men who have sex with men, those in the military, incarcerated patients, athletes (especially those in contact sports or who share equipment), Native Americans, Pacific Islanders, patients with previous MRSA infections, and intravenous drug users.18–21 While it is important to consider MRSA in patients with aforementioned risk factors it is essential not to exclude MRSA in the absence of them.17 Patients presenting with a complaint of a “spider bite” should be investigated for MRSA.18,19,22 In a recent observational study of urban patients, MRSA was isolated from abscesses in 51% of patients.23 An American study of 11 academic centers found MRSA incidence rates as high as 74% in patients presenting with abscesses.17 As much as 77% of MRSA-related illness, especially presenting in the Emergency Department, are skin and soft tissue infections (SSTI).24 CA-MRSA carries the mecA gene, which is thought to impart the antimicrobial resistance. This is carried on the Staphylococcal Cassette Chromosome Type-IV, which is distinct from other forms of MRSA.18,19 CA-MRSA also produces an exotoxin called PantonValentine Leukocidin (PVL) that predisposes patients to cutaneous infections.18,19 PVL has been identified in up to 98% of CA-MRSA cases.17 Up to 17% of abscesses are sterile.1,7,13 Nearly 40% of these are secondary to intravenous drug use and most likely result from injection of necrotizing chemical irritants.3 Viruses (e.g., herpes), autoimmune mechanisms, or systemic illnesses including metastatic tumors, benign tumors, and granulomatous disease may also cause sterile abscesses.4,25 These atypical etiologies may present with the absence of local inflammatory signs and symptoms and only with an exacerbation of the underlying disease process.
SPECIFIC CLINICAL ENTITIES Furuncles, or boils, are acute circumscribed abscesses of the skin and subcutaneous tissue that most commonly occur on the face, neck, buttocks, thigh, perineum, breast, or axilla. Carbuncles are aggregates of interconnected furuncles that frequently occur on the back of the neck where the thick skin causes lateral extension of the infection rather than pointing toward the skin surface. These occur with a higher frequency in diabetics. They can be large and cause systemic signs, symptoms, and complications. Carbuncles often require surgical consultation and treatment in the Operating Room. Hidradenitis suppurativa is a chronic relapsing inflammatory disease process affecting the apocrine glands primarily in the
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axilla, the inguinal region, or both.26 Initially, this process will appear like a typical abscess and is only identifiable in its chronic scarring phase when there are multiple lesions with tender areas of induration and inflammation in various stages of healing. The chronic process leads to draining fistulous tracts that require ongoing surgical management. Emergency Department management involves the usual incision and drainage procedure of any area of fluctuance. Patients should be informed that the intervention is not curative and that the problem is chronic. Arrange a referral to a General Surgeon, Dermatologist, or Plastic Surgeon for long-term follow-up. Up to 80% of breast abscesses occur in nonlactating women.4 Peripheral and superficial lesions are similar to abscesses elsewhere on the body and respond to conservative incision and drainage with an incision that radiates out (centripetally) from the nipple.27 Deeper and periareolar abscesses are often complex and require surgical referral and general anesthesia to properly treat. Postpartum mastitis is common and precipitated by milk stasis and bacterial invasion through a cracked nipple. The offending organism is commonly Staphylococcus aureus or Streptococcus species. Treatment includes the application of heat, oral antibiotics, and continued breast emptying with a breast pump or feeding of the baby. The mastitis may evolve into an abscess and is often associated with systemic symptoms. Appropriate antibiotic therapy and follow-up in 24 to 48 hours is required. Sebaceous cysts are a common cause of a subcutaneous abscess. They can persist for long periods as nontender subcutaneous swellings before becoming infected. They appear like most other abscesses. Sebaceous cysts can be identified by a small punctate sinus tract near the center of the fluctuant area. The initial treatment is incision and drainage. The contents are usually thick cheesy material that needs to be manually expressed. A sebaceous cyst has a definite shiny white capsule that must be excised, preferably at the time of incision and drainage or at the first follow-up visit, to prevent recurrence. The area is then treated as any other healing abscess cavity. The recurrence of an abscess that has been previously drained should suggest the possibility of underlying osteomyelitis, a retained foreign body, or the presence of unusual organisms such as mycobacteria or fungi. Recurrent abscesses should prompt further investigation including an assessment of the patient’s immune status.
SPECIAL CONSIDERATIONS The precise risk for endocarditis associated with subcutaneous abscesses is unknown. Up to 5% of patients with abscesses have bacteremia at the time of presentation.4,16 Incision and drainage of cutaneous abscesses can result in transient bacteremia with the organism causing the abscess.7,14,28 More recently, the clinical relevance of this bacteremia has become controversial.16 At this time, only patients considered to be at high risk for endocarditis are recommended to receive antimicrobial prophylaxis before incision and drainage (Table 106-1).29 Bacterial endocarditis prophylaxis should be directed at the most likely pathogen causing the infection. An antistaphylococcal penicillin or a first-generation cephalosporin is an appropriate choice for most soft tissue infections (Table 106-2). Clindamycin is an acceptable alternative for patients allergic to penicillin. Patients with immunodeficiency and localized soft tissue abscesses may be at higher risk for developing septicemia secondary to bacteremia induced by incision and drainage, but it is unclear if they are at higher risk of complications and death.30,31 These patients may benefit from prophylactic antibiotics prior to incision and drainage, but only indirect evidence and no controlled studies are available.32 High-risk patients with known
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TABLE 106-1 Cardiac Conditions at Risk for Endocarditis that Require Antibiotic Prophylaxis for Incision and Drainage29 Prosthetic cardiac valves—including bioprosthetic and homograft valves Previous bacterial endocarditis Unrepaired cyanotic congenital heart disease (CHD)—including palliative shunts and conduits Repaired CHD with prosthetic material or device—within 6 months after the procedure (regardless of method of placement) Repaired CHD with residual defects at or adjacent to site of prosthetic patch or device Cardiac transplant with cardiac valvulopathy Except for the conditions listed above antibiotic prophylaxis is no longer recommended for any other form of CHD
or suspected MRSA infection should receive IV Vancomycin or Clindamycin when undergoing incision and drainage.29
PATIENT ASSESSMENT Prior to the treatment of an abscess, a focused history should be taken assessing for trauma, intravenous drug use, history of fever, and past medical history. Specifically inquire about diabetes, renal failure, steroid use or other immune suppression, peripheral vascular disease, and valvular heart disease. It is important to note any of the aforementioned risk factors for CA-MRSA as this may alter management of certain patient populations. Past anesthetic history and the potential for aspiration should be assessed if procedural sedation is to be considered.33 Medications and allergies should be queried. The patient’s tetanus status must be confirmed and booster doses provided as required. A brief physical examination documenting function and intact distal neurovascular status of extremities involved is required. Evidence of pain on passive or active movement of fingers may suggest a deep space infection.4 A high index of suspicion is required, especially in injection drug users (IDU), to identify those seemingly simple cutaneous infections that unpredictably
TABLE 106-2 Prophylactic Antibiotic Regimens for Procedures29 Clinical situation Agent Standard general prophylaxis Amoxicillin Unable to take oral medications
Ampicillin
Unable to take oral medications
Cefazolin or Ceftriaxone**
Allergic to penicillin or ampicillin
Cephalexin**
Allergic to penicillin or ampicillin
Clindamycin
Allergic to penicillin or ampicillin
Azithromycin or Clarithromycin
Allergic to penicillin and unable to take oral medications Allergic to penicillin and unable to take oral medications Known or suspected MRSA
Cefazolin or Ceftriaxone** Clindamycin Vancomycin
evolve into extensive necrotizing soft tissue infections.34 General assessment of the airway and cardiopulmonary system, vital signs, and mental status is indicated if procedural sedation is to be employed.33 Routine laboratory studies are not indicated in otherwise healthy individuals. In immunocompromised patients, a CBC looking for leukopenia or toxic granulations should be considered. Diabetics should have electrolytes, BUN, creatinine, and glucose assessed. Elevated potassium in diabetics may indicate myonecrosis.35 Consider a urinalysis for myoglobinuria. Culturing the purulent material from a drained abscess was previously considered to be of little value. Controversy exists today as to the value of culture in abscess management. While many experts suggest that it is of little value because it has no bearing on acute management (curative I & D), others suggest that it is vital to help determine antimicrobial susceptibility and outbreak patterns.22 Cultures should be obtained as they may alter later management in cases with recurrent or refractory infections, those patients who are seriously ill or immunocompromised, patients on an antimicrobial with variable activity, those who have failed surgical treatment, and any patient being admitted to the hospital.22,36 Gram stain and cultures for both aerobic and anaerobic bacteria may be helpful in those patients who are febrile, systemically unwell, immunocompromised, or who present atypically. Consider obtaining radiographs of the affected areas if there is a history of trauma, drug use, or concern regarding deep infection. Foreign bodies and fractures may not be easily identifiable because of the edema and tenderness caused by the infection. Gas or osteolytic lesions on plain radiographs may indicate severe deeper infection, the need for urgent surgical consultation, and prompt antibiotic therapy.37
ULTRASONOGRAPHIC EVALUATION Bedside ultrasound use in the Emergency Department is of great value to the Emergency Physician in evaluating skin and soft tissue infections. This modality can be used to differentiate a cellulitis from an abscess in difficult cases. Ultrasound is portable, inexpensive, comfortable for patients, and provides no radiation
Dose* Adults: 2.0 g Child: 50 mg/kg Adults: 2.0 g Child: 50 mg/kg Adults: 1.0 g Child 50 mg/kg Adults: 2.0 g Child: 50 mg/kg Adults: 600 mg Child: 20 mg/kg Adults: 500 mg Child: 15 mg/kg Adults: 1.0 g Child: 25 mg/kg Adults: 600 mg Child: 20 mg/kg Adults: 1 g Child 20 mg/kg
Timing PO, 30–60 min prior to the procedure IV or IM, 30 min prior to the procedure IV or IM, 30–60 min before procedure PO, 30–60 min prior to procedure PO, 30–60 min prior to procedure PO, 30–60 min prior to procedure IV or IM, 30–60 min prior to procedure IV or IM, 30-60 min prior to procedure IV, 30 min prior to procedure
* Total child dose should not exceed adult dose. ** Cephalosporins should not be used in patients with immediate-type hypersensitivity reactions (urticaria, angioedema, or anaphylaxis) to penicillin.
CHAPTER 106: Subcutaneous Abscess Incision and Drainage
exposure. It is fast and easy to gain proficiency for specific applications.38 Ultrasound is indicated for ambiguous physical findings such as widespread cellulitis, localizing an incision site, and for ruling out dangerous masses such as a pseudoaneurysm that masquerade as an abscess.39 Ultrasonography is helpful in identifying small or early abscesses, deep abscesses, abscesses under previous scars, and for localizing adjacent major vessels or nerves.39 Recent studies have found that ultrasound has a sensitivity of 98% and specificity of 88% in detecting an abscess.38 One study of presumed cellulitis in the Emergency Department found that ultrasound changed the case management in 71 of 126 patients (56%), as swelling thought to be due to cellulitis can hide an abscess.40 In the pediatric population, ultrasound is useful in evaluating a cellulitis and determining if an incision and drainage is necessary.41 Finally, ultrasound can be used to guide an aspiration to confirm the presence of an abscess and to obtain material for culture and gram stain.42 Before ultrasonographic examination, it is important that the Emergency Physician has an appreciation of the anatomical structures of the area. The location and sonographic appearance of arteries, veins, nerves, and tendons should be known before the incision and drainage procedure. Generally, a 5 to 7.5 MHz linear array transducer is used. Some find a standoff pad or gel-filled glove to be useful for superficial structures.39 Once the probe has been electronically focused to an ideal depth, scan the area of infection in two orthogonal planes.39,40 Lower frequency transducers are useful for deeper abscesses, while higher frequency probes are more effective for superficial abscesses. It is important to use probe covers as well as proper cleaning and disinfecting supplies in order to avoid cross contamination. Differentiation between a cellulitis and an abscess on ultrasound is based on several findings. Cellulitis shows diffuse hyperechogenicity and thickening of the skin and subcutaneous fat. The presence of echo-poor strands between hyperechoic fatty lobules in the subcutaneous tissue is known as cobblestoning and is indicative of cellulitis.38,39,42 (Figure 106-1). An abscess has a wider array of presentations on ultrasound. Most frequently, an abscess is a spherical
709
FIGURE 106-2. Ultrasound image showing a large hypoechoic area representing a large superficial abscess.
or elliptical shaped anechoic or echo-poor region with sharper echogenic borders.39,43 (Figure 106-2). Within the echo-poor area there may be gas, lobulations, septations, and echogenic debris. There are some cases where the abscess can appear to be isoechoic and even hyperechoic. In these cases, there may be a role for ultrasoundguided aspiration.43 If unsure if an abscess is present on ultrasound, gentle digital palpation or pressure may induce motion of the purulent material within the abscess.43 Posterior acoustic enhancement can be seen in the presence of an abscess.39 This technique can help rule out similarly presenting hematomas, necrotic tumors, vascular lesions, or schwannomas.42 There is an emerging role for Doppler ultrasound in abscess evaluation. The findings of increased vasculature, peripheral blushing and hyperemia, and increased large vessel flow around the abscess are common (Figure 106-3).44
INDICATIONS The presence of a fluctuant mass in an area of induration, erythema, and tenderness is clinical evidence that an abscess requires incision and drainage. Antimicrobial treatment without incision and
FIGURE 106-1. Ultrasound image of a breast showing cobblestoning of the subcutaneous tissue indicative of edema secondary to cellulitis with echogenic material surrounded by echo-poor areas consistent with early abscess formation.
FIGURE 106-3. Color Doppler ultrasound image showing peripheral hyperemia around a large abscess cavity.
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drainage can lead to treatment failures in patients with abscesses.45 Examination alone may not definitively indicate an abscess, especially if it is deep. This can be further confirmed by bedside ultrasound, with or without needle aspiration.4 Obtaining purulent material on aspiration identifies an abscess and is an indication for incision and drainage.4 If no pus is aspirated, oral antibiotics, warm compresses, and follow-up in 24 hours must be arranged for a reassessment.
CONTRAINDICATIONS The only absolute contraindication to the incision and drainage of an abscess in the Emergency Department is the possible association with a mycotic aneurysm.10,35 Commonly, abscesses overlie large vessels including those in the anterior triangle of the neck, the supraclavicular fossa, the deep space of the axilla, the antecubital fossa, the groin, and the popliteal space.46 In these locations, or if the abscess is pulsatile, fine needle aspiration for blood, diagnostic imaging, and/or angiography is indicated prior to incision and drainage. Relative contraindications to incision and drainage include an inability to achieve adequate anesthesia. An abscess associated with a deep foreign body that requires additional real-time imaging such as a fluoroscopy or ultrasound may require surgical referral.47 Proximity of an abscess to important neurologic, tendinous, or vascular structures may require specialty consultation and magnification in the operating room. Deep space infections or involvement of any joint requires admission for parenteral antibiotic therapy and possible operative debridement. Patients presenting with soft tissue infections exhibiting pain out of proportion to physical examination findings or deep anesthesia of the involved or distal area should raise the possibility of deeper infections such as necrotizing fasciitis or myonecrosis.37 Perirectal and periurethral abscesses are often larger and deeper than they appear and may be complicated by sinus tracts that require exploration under general anesthesia. Manipulation of abscesses in the “danger triangle” of the face (corners of the mouth to glabella) can lead to septic thrombosis of the cavernous sinus. Periorbital or orbital abscesses require ophthalmologic assessment and treatment.
EQUIPMENT Anesthesia • 18 and 27 gauge needles, 1½ in. long • 10 mL syringes • Povidone iodine or chlorhexidine solution • Local anesthetic solution with epinephrine • Local anesthetic solution without epinephrine if abscess is near an end arteriolar system • Ethyl chloride spray • Ice pack Procedure • #11 and #15 scalpel blades on a handle • Two hemostats, in two sizes for breaking up loculations and probing the cavity • Scissors • Normal saline • 10 or 20 mL syringe with a 20 or 22 gauge angiocatheter • Suction source, tubing, and catheter for larger abscesses
• • • • • • • • •
4 × 4 gauze squares Iodoform gauze packing Adhesive tape Culture swabs and vials Ultrasound machine with a 5 to 7.5 MHz probe Ultrasound probe covers Ultrasound gel Standoff pad Ultrasound probe cleaning and disinfecting solutions
PATIENT PREPARATION Explain the procedure, its risks, and benefits to the patient and/ or their representative. Patients should be warned of potential cosmetic complications prior to proceeding. Obtain an informed consent to perform the procedure. If endocarditis prophylaxis is indicated, oral regimens should be given 1 hour prior to the procedure and parenteral regimens within 30 minutes of the procedure (Table 106-1). Clean the skin of any dirt and debris. Apply povidone iodine or chlorhexidine solution to the skin and allow it to dry. Apply drapes to delineate a sterile field. Many Emergency Physicians regard this last step optional. The procedure of cutting into a contaminated abscess is considered to be clean and not sterile.
ANESTHESIA It is usually possible to achieve adequate anesthesia for the skin incision but any additional manipulation may be painful. Local anesthetic infiltration is often less effective than in other procedures. The pH of infected tissue is often low and retards the diffusion of the local anesthetic solution into nerve axons.48 A regional field block can be instituted by injecting a ring of 1% lidocaine or 0.5% bupivacaine subcutaneously approximately 1 cm away from the perimeter of the erythematous border of the abscess. The onset of anesthesia occurs after about 5 minutes. A small amount of local anesthetic solution can be injected intradermally into the roof of the abscess in a linear fashion along the line of the planned incision (Figure 106-4A).4 Be careful during this portion of the procedure as the abscess may be under pressure. The inadvertent injection of local anesthetic solution into the abscess cavity may cause fluid to be forcibly ejected toward the Emergency Physician. Appropriate universal precautions should be employed including a face mask and eye protection. In superficial abscesses or furuncles, which are unlikely to require significant exploration, topical ethyl chloride spray can be used to provide anesthesia. Invert the bottle and compress the spray nozzle to begin the flow of fluid. Direct the spray toward the planned site of incision. The pain relief from ethyl chloride is variable and fleeting. It is also highly flammable.5 The application of an ice pack over the planned incision site secured with an elastic bandage for 15 minutes can also be effective. This may be especially useful for children, those with severe needle phobias, or in cases of a true anesthetic allergy. Nitrous oxide is safe and was previously thought to be effective as an adjunct to the incision and drainage of abscesses.49 More recently, it has been shown to cause no significant reduction in pain and to only be marginally effective as an anxiolytic.50 Procedural sedation with agents such as ketofol (ketamine and propofol in a 50:50 mixture in a dose of approximately 1 mL/kg IV in adults) can be useful in deep abscesses that require extensive probing.51 It is difficult to obtain adequate pain control in these cases, even with a wellperformed field block.
CHAPTER 106: Subcutaneous Abscess Incision and Drainage
711
FIGURE 106-4. Incision and drainage of a subcutaneous abscess. A. Infiltration of local anesthetic solution over the abscess. B. A straight incision to drain the abscess. C. An elliptical incision to drain the abscess. D. The wound is irrigated with sterile saline. Any pockets of pus are opened by blunt dissection with the hemostat. E. The wound is packed open.
TECHNIQUES ASPIRATION Aspiration is performed as a diagnostic procedure in cases of soft tissue infections where the presence of an abscess is unclear, a mycotic aneurysm must be ruled out, or samples for Gram stain and culture are required. Aspiration is not a therapeutic procedure in and of itself. Anesthetize the skin. If ultrasound is available, locate the abscess cavity and try to determine the shortest needle path. Insert an 18 gauge needle attached to a 10 mL syringe into the skin. On ultrasound, the needle should appear as a bright, hyperechoic line with posterior reverberation artifact.42 As the needle penetrates deeper, it should become increasingly oblique. Apply negative pressure to the syringe. Advance the needle into the area where pus or blood is presumed to be loculated. The procedure should be terminated and incision and drainage should be performed immediately if pus is obtained on aspiration. Anaerobic and aerobic culture bottles should be inoculated directly from the syringe if cultures are indicated. Simple swabbing of the purulent material after incision and drainage is inadequate for growth of anaerobic organisms. If blood is aspirated, terminate the procedure and apply firm pressure to the area to prevent a hematoma from forming. Angiography with surgical consultation should immediately follow. If no pus or blood is aspirated, redirect the needle in several directions to confirm the absence of an abscess. Discharge the patient with oral antibiotics, warm compresses, and follow-up in 24 hours for a reassessment.
INCISION AND DRAINAGE Make an incision spanning the entire area of fluctuance and parallel to the relaxed skin tension lines to reduce scarring.35 A
straight incision with a #11 scalpel blade is usually performed (Figure 106-4B). An elliptical incision with a #15 scalpel blade is an alternative and often results in a similar appearing final scar (Figure 106-4C). The purpose of the elliptical incision is to remove a full thickness wedge of tissue so that the wound will remain open. This type of incision should not be made in cosmetically sensitive areas (e.g., face, neck, or breasts) or in areas with minimal subcutaneous tissue (e.g., hands and feet). It is important to ensure a large enough incision to promote adequate drainage with the exception of cosmetically sensitive areas where a stab incision may be initially attempted to limit scar formation.5 Debride any necrotic or devitalized tissue. Probe the cavity by inserting a hemostat. Gently spread the jaws open to break up any loculations and to release any further pockets of purulent material (Figure 106-4D).6 Rotate the hemostat around the entire abscess to break any loculations. A scalpel should not be used for the blunt dissection of an abscess cavity as it may cause additional tissue damage and bacteremia.14 Remove the tough shiny capsule by grasping the edges with a hemostat and applying firm traction if the abscess is due to an infected sebaceous cyst. The capsule can often be removed intact. Irrigate the abscess cavity with an 18 gauge angiocatheter attached to a 10 mL syringe containing sterile saline (Figure 1064D). This will flush away all loosened purulent and necrotic material. Loosely pack iodoform gauze into the abscess cavity (Figure 106-4E). Leave 1 to 2 cm of gauze exiting from the cavity to prevent the incision from sealing over and ensure an adequate drainage tract for the cavity. The value of antiseptic impregnated gauze over plain gauze is uncertain. Do not over pack the abscess cavity as this may interfere with the inflammatory hyperemia necessary for healing or retard drainage and reproduce “abscess-like” conditions.6 Apply an absorbent dressing of 4 × 4 gauze over the
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wound. Splinting and elevation of the affected area may be beneficial in select patients (e.g., young patients and confused patients).
AFTERCARE The majority of available evidence suggests that incision and drainage of subcutaneous abscesses alone is adequate treatment and additional antimicrobial therapy is unnecessary in healthy patients with no major comorbidities. Many recent studies involving abscesses, including those caused by MRSA, have demonstrated that patients have similar outcomes regardless of whether or not appropriate antibiotics were used after an abscess incision and drainage.17,24,52–54 A pediatric study demonstrated 94% resolution with incision and drainage alone in patients with abscesses smaller than 5 cm in diameter.52 Some conflicting evidence from a retrospective cohort found ancillary antimicrobial treatment active against MRSA had a resolution of 95% while those patients not receiving antimicrobial treatment had a resolution of only 87%.55 Consider empiric antimicrobial therapy active against MRSA in cases involving multiple lesions, cutaneous gangrene, immunocompromised patients, extensive surrounding cellulitis, systemic toxicity, unusual pathogens, and in patients requiring hospitalization.36,56 Further, recommendations from the Center for Disease Control suggest antibiotics after incision and drainage in those with rapid progression, comorbidities such as diabetes mellitus, HIV, neoplastic disease, those patients at extremes of age, abscesses in locations that are difficult to drain or have a risk of septic phlebitis associated with it, and lack of response to incision and drainage alone.19 Pediatric patients with abscesses greater than 5 cm should also receive empiric antimicrobial therapy.52 An oral antibiotic such as cephalexin can be a good first choice for healthy individuals in areas where the prevalence of MRSA is extremely low.19 Knowledge of local MRSA prevalence and antimicrobial susceptibility patterns are paramount when selecting the appropriate antibiotic.19,36 If more than 10% to 15% of community Staphylococcus aureus isolates are MRSA, empiric treatment with agents that show activity against MRSA is warranted.57 Current guidelines for outpatient therapy suggest using trimethoprimsulfamethoxazole, Clindamycin, Doxycycline, Minocycline, or Linezolid. Rifampin can be added to many of these antimicrobials, but should not be used alone. IV therapy for patients with significant comorbidities and signs of systemic infection should include either Vancomycin, Daptomycin, Linezolid, or Tigecycline.22,56 Trimethoprim-sulfamethoxazole, Clindamycin, and Doxycycline (if over the age of 7 years) are recommended in healthy children.58 More serious infections should be approached with IV Vancomycin or Clindamycin, with the addition of nafcillin or gentamicin, and admission to the hospital.58 The addition of an agent active against Group A Streptococcus is also recommended in cases with a severe surrounding cellulitis.19 Current literature and consideration of the local antibiotic resistance patterns should guide antimicrobial selection.19,56,59 Follow-up in 24 to 48 hours to remove the packing and assess the response to therapy should be arranged. Pain can be adequately controlled with the use of acetaminophen or nonsteroidal anti-inflammatory drugs. Narcotic analgesics are rarely required. Instruct the patient to immediately return to the Emergency Department if they develop fever, chills, increased pain, increased swelling, or increased redness to the surrounding skin. Repack the cavity approximately every 48 hours until granulation tissue is developing throughout the wound and the drainage tract is well established if a large amount of drainage continues.15,60 At that time, the remaining packing is removed and the patient is instructed to soak the area in warm water three to four times per day.3 Healing
occurs in 5 to 9 days in most cases.4,6,15 The patient may be discharged from medical care when all signs of infection (i.e., erythema, drainage, pain, and induration) have resolved.
FUTURE ADVANCES IN ABSCESS MANAGEMENT It is currently standard practice to pack an abscess cavity after an incision and drainage. Packing is used for hemostasis, to keep the abscess cavity from closing prematurely, and to debride the abscess cavity. Packing an abscess cavity can be painful and requires multiple follow-up visits. These visits are at an additional cost to the patient. A small, prospective study of noncomplicated abscesses found not packing an abscess cavity resulted in less pain, less analgesic use, and no increased morbidity.62 Further studies are required before any definitive recommendation can be made regarding to pack or not to pack an abscess cavity. Abscesses are currently allowed to heal by granulation. This process can take weeks and results in large scars. Primary suture closure after incision and drainage has been used around the world except in the United States.63,64 This treatment can reduce scarring, reduce pain, and promote faster healing. Most of the studies involve a small number of patients, administered preprocedural antibiotics, and were performed in the Operating Room. Further studies are required before this change in practice can be recommended for the Emergency Department management of abscesses.
DECOLONIZATION AND PREVENTION The role of decolonization regimes after incision and drainage does not have established effectiveness.19 However, a decolonization regimen may play a role in those patients with recurrent infections, those not responding to therapy, or in patients with a closely associated cohort at risk (e.g., infirmed family, sports teams, or the institutionalized).36 A recent randomized controlled trial of 2% chlorhexidine gluconate wash, 2% mupirocin intranasal ointment and oral rifampin, and doxycycline for 7 days found that after 3 months, 74% of patients were free of MRSA colonization.61 This number dropped to 54% at 8 months post-treatment.61 Colonization rates vary by geography and colonization is considered a risk factor for MRSA infection. However, decolonization is not routinely recommended due to limited supporting evidence, poor patient compliance, and the risk of increasing antibiotic resistance.22 Patient education is the most effective way to reduce the spread of infection and recurrent infections from MRSA.19,22 Maintaining a clean and dry wound, frequent handwashing and bathing, avoiding sharing any personal items at all (athletic or otherwise), laundering clothing that has come into contact with the wound, avoiding skin to skin contact and disinfecting equipment and other surfaces are essential recommendations that should be made to outpatients with MRSA skin and soft tissue infections.19
COMPLICATIONS Complications resulting from the incision and drainage of an abscess are uncommon. In most cases, some scarring will result from deliberate open packing and secondary intention granulation of the wound. Infectious complications, including inciting bacterial endocarditis as discussed earlier, are possible. Endocarditis can be avoided with appropriate screening of patients and the administration of prophylactic antibiotic therapy in patients at risk. Precipitation of septicemia because of transient bacteremia in an immunodeficient patient must be considered prior to the procedure. Incision and drainage of a mycotic aneurysm should not occur if an appropriate assessment is completed prior to making the incision.
CHAPTER 107: Paronychia or Eponychia Incision and Drainage
SUMMARY Simple incision and drainage under local or regional anesthesia in the Emergency Department can effectively treat most subcutaneous abscesses. Adjunctive procedural sedation may be required to adequately probe a deep cavity. A directed history and physical examination will identify those who may require additional lab work, imaging, specialty consultation, and follow-up. The majority of patients will not require antibiotics, although there may be a role for ancillary treatment in selected patients with MRSA infections. Attention must be paid to requirements for endocarditis prophylaxis and consideration given to the possibility of inducing bacteremia in any given patient.
Paronychia or Eponychia Incision and Drainage
107
Lisa R. Palivos
INTRODUCTION A paronychia is an infection or abscess of the tissues around the base and along the sides of the nail plate. It is the most common infection in the hand.1 A paronychia can be located on the fingers or the toes. It occurs in all age groups. It can cause significant pain and discomfort leading to a visit to the Emergency Department. A paronychia initially presents with redness, swelling, and tenderness along the edges of the nail plate. This can progress to an abscess that requires drainage. An infection that extends to the overlying proximal cuticle is termed an eponychia. This chapter discusses the treatments, which vary with the extent and the location of the infection.
ANATOMY AND PATHOPHYSIOLOGY The dorsal aspect of the distal digit consists of the nail plate, the nail bed (matrix), and the perionychium (Figure 107-1). The nail bed is situated beneath the nail plate and is responsible for growth of the nail. The perionychium consists of the soft tissue surrounding the nail plate (eponychium and lateral nail folds). A paronychia is usually the result of frequent trauma, tight fitting apparel (e.g., gloves, pantyhose, and shoes), aggressive manicures,
Distal interphalangeal joint Eponychium (proximal nail fold)
the use of artificial nails, hangnails or ingrown nails, or nail biting.2 A disruption of the seal between the nail plate and nail fold allows bacteria to enter, leading to pus formation in the eponychial space (Figure 107-1). It begins as a swelling and erythema in the dorsolateral corner of the nail fold that can progress to an abscess. A paronychia can grow and spread to adjacent structures and result in a felon, an osteomyelitis, or a tenosynovitis. Many paronychias are polymicrobial, containing both aerobic and anaerobic organisms.14 The most common organism to cause a paronychia is Staphylococcus aureus.3 In children and nail biters, paronychias are often caused by anaerobes secondary to finger sucking or nail biting.4 Gramnegative organisms should be considered in immunocompromised hosts. Chronic paronychias are the result of separation of the nail from the nail plate, which leaves a space for bacteria and fungi to collect.12 These infections are usually caused by Candida albicans.5
INDICATIONS An early paronychia with signs of cellulitis may be treated nonsurgically. This requires frequent warm soaks (e.g., water, vinegar, or Burow’s solution), immobilization, elevation, topical antibiotics (e.g., bacitracin or Mupirocin) with or without topical corticosteroids, and follow-up in 24 hours.2,6,11,12 Paronychia resistant to these measures should be treated with oral antibiotics to cover Staphylococcus, plus anaerobic coverage if nail biting or finger sucking were causative agents.12 Amoxicillin/clavulanate, clindamycin, and trimethoprimsulfamethoxazole are commonly used antibiotics. Take into account the prevalence of methicillin-resistant Staphylococcus aureus in your community when deciding upon the choice of antibiotic. A progression of the infection results in fluctuance and the formation of an abscess. The digital pressure test may be used to diagnose the presence of an abscess when the exam is otherwise equivocal. Instruct the patient to oppose the thumb and affected finger and apply light pressure to the distal volar aspect of the affected digit. If an abscess is present, the skin under the nail plate will blanch.10 The presence of an abscess, fluctuance, or pus beneath the nail plate requires an incision and drainage procedure. This procedure will relieve the patient’s pain, promote healing, and prevent complications from local extension into surrounding bone and soft tissues.
CONTRAINDICATIONS A herpetic whitlow is a herpes simplex virus infection of the distal phalanx that can be confused with an early paronychia or felon. The presence of multiple clear vesicles that coalesce suggests a herpetic whitlow. The herpetic whitlow is a nonsurgical and self-limited infection. Treatment consists of a dry dressing to the affected finger in order to prevent autoinoculation and transmission of the infection, oral antiviral agents, and analgesics. Incision and drainage is not recommended, will prolong the recovery, and lead to secondary bacterial infection.7 A chronic paronychia should be referred to a Hand Surgeon or Dermatologist for treatment.
EQUIPMENT Perionychium
Lateral nail fold Nail plate Paronychia Hyponychium FIGURE 107-1. The distal finger illustrating a paronychia and the surface anatomy.
713
• • • • • • • •
Povidone iodine or chlorhexidine solution Sterile gloves #11 scalpel blade or an 18 gauge needle Local anesthetic solution without epinephrine 18 and 27gauge needles 5 to 10 mL syringe Ethyl chloride spray Forceps
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SECTION 7: Skin and Soft Tissue Procedures
Mosquito hemostat Ribbon-gauze packing, ½ in. wide Petrolatum gauze, ½ in. wide Scissors 4 × 4 gauze squares 18 gauge angiocatheter 20 mL syringe Sterile saline Adhesive tape
PATIENT PREPARATION Explain the procedure, its risks, and benefits to the patient and/or their representative. Obtain an informed consent for the procedure. Assess and update the patient’s tetanus immune status if indicated. Place the patient on a gurney with the extremity on a bedside procedure table in a well-lit room. Soak the digit in warm water for 5 minutes to soften the skin. Perform a digital nerve block if the patient is apprehensive, has significant tenderness, or if it is not a simple paronychia or eponychia. Refer to Chapter 126 for the complete details regarding digital anesthesia techniques. Alternatively, apply ethyl chloride spray to the area until the skin turns frosty and pale. Apply povidone iodine or chlorhexidine solution circumferentially to the distal digit and allow it to dry. The digit can be secured to a sterile tongue depressor for better control, especially in uncooperative children.
Portion of nail to be removed
A Small incision may be necessary
B Petrolatum gauze FIGURE 107-3. Removal of the lateral nail plate is required when pus extends laterally below the nail plate. A. The dotted line over the nail represents the incision required to remove the nail plate. An additional incision may be required on the eponychium. B. The lateral portion of the nail plate has been removed and petrolatum-gauze packing has been inserted to keep the nail fold elevated from the nail bed.
TECHNIQUES SIMPLE PARONYCHIA OR EPONYCHIA There is no need for a skin incision in an uncomplicated paronychia or eponychia. Simply lifting the eponychium off the nail plate at the point of maximal tenderness and/or fluctuance is usually curative. Slide the tip of a #11 scalpel blade (or an 18 gauge needle) under the paronychia, or eponychia, at the site of maximal fluctuance (Figure 107-2). Advance the scalpel blade to lift the soft tissue from the nail plate until there is an efflux of purulent fluid. Apply digital pressure to the area to express the pus. Gently place a hemostat under the soft tissue to break any loculations. Irrigate the pocket with an angiocatheter on a syringe containing sterile saline. Packing a paronychia is controversial and physician-dependent. Place a small piece of ribbon gauze or petrolatum gauze under
the elevated soft tissue followed by a simple dressing. If packing is not performed, apply an antibiotic ointment followed by a simple dressing or bandage. Oral antibiotics are not recommended for an uncomplicated paronychia or eponychia.
PARONYCHIA WITH EXTENSION UNDER THE LATERAL NAIL PLATE A more extensive incision and drainage is required when pus accumulates laterally and beneath the nail plate. Remove the lateral nail plate to allow adequate drainage (Figure 107-3A). Use scissors to cut the nail plate longitudinally. Aim the point of the scissors upward and against the undersurface of the nail plate to prevent injuring the nail bed. Remove the lateral nail plate with a hemostat. A small (2 to 3 mm) incision may be required in the corner of the nail fold to remove the nail plate (Figure 107-3A). This will result in the egress of pus. Irrigate the area with saline. Insert a small piece of petrolatum gauze under the nail fold (Figure 107-3B). This will prevent the nail fold from fusing to the nail bed.
PARONYCHIA WITH EXTENSION UNDER THE PROXIMAL NAIL PLATE
FIGURE 107-2. Drainage of a simple paronychia or eponychia. The eponychial fold is elevated from the nail plate with a #11 scalpel blade. Note that the blade is parallel to the nail plate, thereby avoiding injury to the nail matrix and not incising the skin.
A paronychia with extension under the proximal nail plate also requires the removal of a portion of the nail plate (Figure 107-4). Make two 3 to 4 mm long incisions at the corners of the nail folds (Figure 107-4A). Cut the proximal one-third of the nail plate with scissors (Figure 107-4B). Aim the point of the scissors upward and against the undersurface of the nail plate to prevent injuring the nail bed. Grasp and remove the proximal segment of the nail plate with a hemostat. This will result in the egress of pus. Irrigate the area with saline. Insert a piece of petrolatum gauze under the nail fold to prevent it from fusing to the nail bed (Figure 107-4C). Removal of the entire nail is rarely necessary except in the case of an extensive subungual abscess. An alternative to nail removal
CHAPTER 107: Paronychia or Eponychia Incision and Drainage
715
coexists with S. aureus.5,6 Initial treatment typically includes avoiding the noxious exposure, topical emollients, and antifungals.13 Definitive treatment for a chronic paronychia is eponychial marsupialization. This involves removal of a crescent-shaped piece of skin proximal to the nail fold and parallel to the eponychium, extending from the radial to ulnar borders. In addition to marsupialization, complete or partial nail removal may be necessary if nail ridging is present.9 A chronic paronychia may be confused with another condition that looks similar and mimics a chronic paronychia such as cysts, foreign body reactions, malignancies, psoriasis, and verrucae. Refer all chronic paronychia to a Hand Surgeon due to the higher rate of recurrence, the complexity in management, and where follow-up care can be more consistent.
AFTERCARE
FIGURE 107-4. Removal of the proximal nail plate is required when pus extends proximally below the nail plate. A. Two incisions are required through the eponychium, represented by dotted lines. B. The dotted line over the nail plate represents the incision required to remove the nail plate. C. The proximal portion of the nail plate has been removed and petrolatum-gauze packing has been inserted to keep the nail fold elevated from the nail bed.
Immobilize and elevate the digit. Instruct the patient to avoid nail biting or sucking. Any discomfort can be treated with acetaminophen or nonsteroidal anti-inflammatory medications. Follow-up care in 24 hours is important as complications can occur despite proper Emergency Department management. Packing of a simple paronychia should be removed in 24 hours. Warm soaks can begin immediately if packing is not placed. Otherwise, warm soaks should be delayed until the packing is removed in 24 hours. There is no evidence that oral antibiotics improve outcome after the incision and drainage of a simple and uncomplicated paronychia. Oral antibiotics are not necessary unless the nail bed is involved, there is apparent cellulitis of the surrounding tissue, or if there are systemic signs of infections such as lymphangitis and fever.6 Patients should return to the Emergency Department if they develop a fever, reaccumulation of pus, redness extending up the finger and hand, or increased tenderness to the digit. Most simple paronychias resolve within a few days. If they persist longer or recur, consult a Hand Surgeon for more aggressive management, such as eponychial marsupialization and nail plate removal. Paronychia or eponychia that extend under the nail plate require follow-up in 24 hours. The packing must be maintained between the nail fold and the nail bed for at least 5 to 7 days. The nail fold will fuse to the nail bed if the packing is removed too soon and a new nail plate will not form. These infections require a 5 to 7 day course of oral antistaphylococcal antibiotics. Nonsteroidal anti-inflammatory medications supplemented with occasional narcotic analgesics will provide adequate pain control for these patients.
COMPLICATIONS is trephination with a heated paper clip or a microcautery unit.8 A large opening or multiple holes are required with this technique in order to eliminate the pus. Refer to Chapter 102 for the complete details regarding trephination.
CHRONIC PARONYCHIA A chronic paronychia occurs from recurrent episodes of inflammation or from neglected infections. It is much more difficult to treat and eradicate than an acute infection. A chronic paronychia is seen frequently in immunosuppressed patients, such as those with diabetes or cancer. These effects are due to the disease process, such as in diabetes, or due to effects of treatment, as seen with certain HIV drugs and chemotherapeutic agents.12 A chronic paronychia is also common in people who wash their hands often, such as dishwashers and healthcare providers. It can also be due to frequent contact with chemicals, finger biting or sucking, and cuticle trimming. The most frequently isolated organism is C. albicans, which commonly
Complications, even in a properly drained paronychia, include a felon, osteomyelitis of the distal phalanx, and a tenosynovitis. Superinfection with C. albicans or other fungi can also occur. These complications can be due to the paronychia itself or from an inadequate incision and drainage procedure. Complications from the incision and drainage procedure are rare if it is properly performed. Care must be taken if the lateral or proximal nail plate is removed to avoid damaging the underlying matrix so that a nail deformity does not result. Fusion of the nail fold to the nail bed will result in a new nail not being formed. Inadequate drainage can result in the infection spreading to adjacent bone and soft tissues. Incision of the skin instead of elevating it off the nail plate can result in prolonged healing.
SUMMARY A paronychia is one of the most common hand infections. The treatment depends on the extent and location of the infection. The incision and drainage procedure is quick, simple, and easy to perform.
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Simple paronychias require elevation of the nail fold with no incision. A more extensive incision and drainage is required along with nail excision when pus accumulates below the nail plate. Follow-up is critical as complications may occur, even when the Emergency Department treatment is optimal.
108
Felon Incision and Drainage
INDICATIONS
Lisa R. Palivos
INTRODUCTION A felon is a subcutaneous infection or abscess in the pulp space on the volar surface of the distal phalanx. It is usually caused by penetrating trauma, an abrasion, spread from adjacent tissues (e.g., eponychium, osteomyelitis, or paronychia), or a minor cut with invasion of bacteria. A felon can also develop in the presence of a foreign body, such as a wood splinter or a thorn.1 It can be iatrogenic from multiple fingersticks for glucose determination.2 The offending organism is usually Staphylococcus aureus. Mixed infections and gram-negative infections may occur in the immunocompromised patient. A felon can less commonly occur on the toes. The information in this chapter can be applied to a felon of the finger or the toe.
ANATOMY AND PATHOPHYSIOLOGY Felons initially present with a gradual onset of pain and erythema of the distal volar finger. Intense throbbing pain, warmth, and swelling develop with the formation of an abscess as the infection progresses. The proper treatment for a felon is incision and drainage. There are multiple techniques to incise and drain a felon. The patient requires digital elevation, immobilization, oral antistaphylococcal antibiotics, oral analgesics, and close follow-up to prevent complications following the incision and drainage.3–7 The distal finger consists of a closed compartment that is bound by the nail plate dorsally, by the skin ventrally and distally, and by the flexion crease proximally (Figure 108-1). This pulp region is divided by multiple (up to 15 or 20) vertical fibrous septa.8 These
Nail plate Nail bed matrix
Extensor digitorum Cuticle tendon (eponychium) Middle phalanx
Distal phalanx Nerves
Septa
Arteries Distal anterior closed space (pulp)
septa extend from the volar surface of the fat pad to the periosteum of the distal phalanx. They divide and compartmentalize the pulp area. When an abscess occurs, it is confined by the septa. They also limit the proximal spread of an infection. Unfortunately, they also inhibit the abscess from reaching the surface and inhibit drainage after the incision and drainage procedure. Blood is supplied by branches of the digital arteries that run parallel and lateral to the phalanx and terminate in the pulp region. The terminal branches of the digital nerves lie palmer and superficial to the arteries. The flexor digitorum profundus tendon inserts on the volar surface of the proximal distal phalanx.
Flexor digitorum profundus tendon
FIGURE 108-1. Midsagittal section demonstrating the anatomy of the distal finger.
All felons that are fluctuant should be incised and drained. Volar digital pads that are tense, tender, painful, and suspected of containing a felon should be incised and drained regardless if fluctuance is palpated or not.
CONTRAINDICATIONS Felons that are not yet fluctuant, as in an early infection, may be treated with warm soaks, elevation, oral antibiotics, and follow-up in 24 hours.6,7 A herpetic whitlow can sometimes be confused with a felon.5,9 A herpetic whitlow can be clinically distinguished by the presence of multiple vesicles and a history of recurrence or simultaneous genital or oral lesions. Treatment of a herpetic whitlow is nonsurgical and consists of a protective dry dressing, oral antiviral agents, and analgesics. Incision and drainage of a herpetic whitlow may spread the virus and predispose the patient to secondary bacterial infection.9 Consult a Hand Surgeon for complicated felons. This includes a felon that is associated with lymphangitis, osteomyelitis, a tenosynovitis, an infection that has spread proximal to the distal interphalangeal joint, or if the patient is immunocompromised. These patients require hospital admission, intravenous antibiotics, and possible incision and drainage in the Operating Room.
EQUIPMENT • • • • • • • • • • • • • • • • •
Povidone iodine or chlorhexidine solution Sterile gloves #11 scalpel blade on a handle Local anesthetic solution without epinephrine 18 and 27 gauge needles 5 or 10 mL syringe 20 mL syringe Ethyl chloride spray Sterile saline 18 gauge angiocatheter Mosquito hemostat Ribbon gauze, ½ in. wide Bandage material Digital splint (plaster, preformed, or tongue depressor) Sling Digital tourniquet, optional Aerobic and anaerobic culture bottles, optional
PATIENT PREPARATION Explain the procedure, its risks, and benefits to the patient and/or their representative. Obtain an informed consent for the procedure. Assess and update the patient’s tetanus immune status if indicated.
CHAPTER 108: Felon Incision and Drainage A
717
Gently probe the loculations with a mosquito hemostat. Irrigate the wound with an 18 gauge angiocatheter on a 5 or 10 mL syringe containing sterile saline. Place a piece of ribbon gauze into the wound. Apply a dry bulky dressing.
B
ALTERNATIVE TECHNIQUES Avoid distal digital nerves
FIGURE 108-2. Recommended incisions for the incision and drainage of a felon. A felon should be incised and drained in the area of maximal fluctuance. A. The longitudinal fat pad incision over the area of maximum fluctuance. B. The unilateral longitudinal incision is high, lateral, and just below the level of the nail.
Some physicians prefer to obtain anteroposterior and lateral radiographs of the digit to rule out an osteomyelitis or foreign body prior to performing the procedure. A positive radiograph for osteomyelitis will alter the time course for antibiotic therapy and require follow-up with a Hand Surgeon. Place the patient on a gurney with the extremity on a bedside procedure table in a well-lit room. Soak the digit in warm water for 5 minutes to soften the skin. Perform a digital nerve block if the patient is apprehensive, has significant tenderness, or if it is not a simple felon. Refer to Chapter 126 for the complete details regarding digital anesthesia techniques. Alternatively, apply ethyl chloride spray to the area until the skin turns frosty and pale. Apply povidone iodine or chlorhexidine solution circumferentially to the distal digit and allow it to dry. Apply sterile drapes to delineate a sterile field. The digit can be secured to a sterile tongue depressor for better control, especially in uncooperative children. The application of a digital tourniquet to create a bloodless field is optional.
TECHNIQUES Multiple incisions can be employed. Make an incision in the area of greatest fluctuance or tenderness with a #11 scalpel blade.3–6 Make a longitudinal incision if the maximal tenderness is in the center of the pulp of the distal fingertip (Figure 108-2A). The incision should not come within 4 mm of or cross the crease of the distal interphalangeal joint as this can lead to injury of the flexor digitorum longus tendon or the joint, flexor tenosynovitis, and flexion contractures.7 Make the incision along the lateral surface of the finger if the felon has maximal tenderness on the radial or ulnar aspect of the finger (Figure 108-2B). Purulent and/or bloody pink fluid will exit from the incision. While not required, consider obtaining aerobic and anaerobic cultures of the purulent material.
A
B
C
Alternative incisions have been advocated but are not recommended because they have higher complication rates (Figure 108-3). These incisions can result in neurovascular injury, painful scars, and altered fingertip sensation. The hockey stick incision can result in digital nerve injury and produce numbness to the fingertip (Figure 108-3A).5 The through-and-through or bilateral longitudinal incision can result in bilateral digital nerve injury and complete anesthesia of the fingertip (Figure 108-3B).6 The transverse palmar incision may transect the digital neurovascular bundles (Figure 108-3C). The fishmouth or horseshoe incision is very extensive, can take a long time to heal, produces a large scar, and an unstable pulp (Figure 108-3D).5
AFTERCARE Splint the involved digit. Provide the patient a sling to keep the hand elevated. Since the incidence of community-acquired methicillinresistant Staphylococcus aureus (CA-MRSA) skin and soft tissue infections presenting to the Emergency Department are increasing, an oral antibiotic effective against CA-MRSA is recommended.10,11 Depending on local resistance patterns, sulfamethoxazole-trimethoprim, doxycycline, or clindamycin are appropriate choices for a 7 to 10 day course. Nonsteroidal anti-inflammatory medications supplemented with narcotic analgesics will control any postprocedural pain. Instruct the patient to soak the digit in warm water several times a day to speed healing. Patients should immediately return to the Emergency Department if they experience fever, increased pain, difficulty using the finger, redness of the finger or hand or arm, or a discharge from the wound. The patient should be reevaluated in 24 to 48 hours for removal of the gauze and inspection of the digit. Remove the gauze during the follow-up visit. Perform a digital or metacarpal block for patient comfort. Irrigate the wound with sterile saline and break up any further loculations, if needed. Replace the gauze for another 24 to 48 hours if there is continued drainage.
COMPLICATIONS Untreated or mistreated felons may cause skin necrosis, osteitis or osteomyelitis of the distal phalanx, septic arthritis of the distal interphalangeal joint, extension of the infection into the palm and adjacent fingers, suppurative tenosynovitis, and lymphangitis.12 Flexor tenosynovitis can occur if the incision is extended too far proximally and too deep. Improperly placed incisions can result in injury
D
FIGURE 108-3. Incisions not recommended for the drainage of a felon. A. The hockey stick incision. B. The through-andthrough or bilateral longitudinal incision. C. The transverse palmar incision. D. The fishmouth incision.
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to the flexor digitorum profundus tendon or the distal interphalangeal joint, mobility of the pad of the finger, neurologic compromise, and/or vascular compromise. The lack of improvement within 24 to 48 hours requires consultation with a Hand Surgeon.
SUMMARY Felons require incision and drainage. The procedure is quick, simple, and easy to perform. The incision should be made at the point of maximal fluctuance while avoiding injury to the digital arteries, digital nerves, the flexor digitorum profundus tendon, and the distal interphalangeal joint. Close follow-up is mandatory to prevent any complications. Consult a Hand Surgeon for any complications associated with the felon.
109
Pilonidal Abscess or Cyst Incision and Drainage Lauren M. Smith
FIGURE 109-1. Pilonidal sinuses occur in the midline, approximately 4 to 5 cm above the anus and in the natal cleft.
INTRODUCTION Controversy surrounds pilonidal disease, from who first described it, to the etiology, and how to manage it surgically. Some believe that pilonidal disease was first described in 1880 by Hodges.1 However, others say it was first described in 1833 by Mayo.2 Hodges used the term “pilonidal sinus” to describe a chronic infection that contained hair and was usually found between the buttocks. The word “pilonidal” comes from “pilus” or hair and “nidus” or nest. It literally means “nest of hair.” The condition did not receive much attention until it became a significant problem in the armed services around the time of World War II. In 1940, in the United States Navy, the number of sick days caused by pilonidal disease and its complications exceeded those of either syphilis or hernias.3 This condition was coined as “jeep disease” by Buie in 1944 because of the high occurrence rate in those that drove or were frequent passengers in military vehicles.4 Pilonidal sinus disease primarily affects Caucasian males. Blacks are infrequently affected and the condition is rare in Asians and Indians. Males are affected three to four times more frequently than females. The affected females tend to be younger than males.19 The condition is prevalent from the onset of puberty to young adulthood and is rare after the age of 40. The peak age of incidence is 21 years. The increased incidence in adolescents and young adults is attributed to hormonal effects of increased hair on the torso, increased activity of sebaceous and sweat glands, fat deposition on the buttocks, and deepening of the gluteal cleft. Other risk factors may include hirsutism, obesity, and poor personal hygiene. Repeated trauma to the area may also contribute to the formation of pilonidal disease. There is an increased prevalence in drivers and others with occupations requiring long periods of sitting.6,7 Patients with pilonidal sinus disease may present with three different clinical pictures: asymptomatic disease, an acute abscess, or chronic disease. Asymptomatic disease patients have a painless sinus pit at the top of the natal cleft. Patients with chronic disease may have mild discomfort and a chronically draining sinus in the upper gluteal region. Approximately 50% of patients with symptomatic pilonidal disease will present acutely with severe pain and frequently swelling that is indicative of a pilonidal abscess that necessitates incision and drainage.8,9 Inspection will reveal one or more midline sinus tract openings, often with protruding tufts of hair. The area will be tender, erythematous, and indurated when an abscess is present. Fluctuance and swelling may not be readily
appreciated. The sinuses may be quite extensive depending upon the chronicity of the disease process prior to presentation.
ANATOMY AND PATHOPHYSIOLOGY A pilonidal sinus consists of a characteristic midline opening, or series of openings, in the upper aspect of the gluteal cleft and approximately 4 to 5 cm from the anus (Figure 109-1). The skin enters the sinus giving the opening a smooth edge. This primary tract leads into a subcutaneous cavity that contains granulation tissue and often a nest of hairs (Figure 109-2). The hairs may be seen projecting through the skin opening. Many sinuses have lateral or secondary openings (fistulas) extending from the pilonidal abscess (Figure 109-2). There have been various opinions as to the etiology of the condition since the first description of the disease. In the first half of the twentieth century, it was generally attributed to a congenital lesion. Some authors believed that the pilonidal sinus originated from a remnant of the medullary canal that subsequently became infected. However, pilonidal disease can form in other areas of the body that lack hair, as some barbers have experienced in interdigital spaces.10,11 Currently, it is widely accepted that pilonidal disease is acquired.5 Some of the contributing factors to this belief are the
FIGURE 109-2. Cross section through a pilonidal abscess and sinus. A primary tract and skin pit leads to the subcutaneous abscess. There may be secondary or lateral openings (fistulas).
CHAPTER 109: Pilonidal Abscess or Cyst Incision and Drainage
rate of recurrence after excision, occurrence at other sites than the gluteal cleft, and the frequency seen among certain populations (i.e., barbers, armed forces, etc.).10,11 Loose hairs from the adjacent gluteal region are thought to form a bristly tuft and penetrate into the skin, perhaps in an area of skin irregularity. This process may be aided by pressure on the region in persons with occupations that require long hours of driving or sitting. The hairs may also be pulled in by a suction effect between the moving buttocks. The hair penetrates the skin and causes a foreign body reaction and secondary inflammation with the potential for infection and abscess formation. The sinuses spread cranially and laterally. They rarely approach the anus and generally remain superficial to the presacral fascia.9,10,12
• • • • • • • • • •
719
Skin razor 10 mL syringe 25 or 27 gauge needle, 2 in. long Local anesthetic solution with epinephrine, lidocaine, or bupivacaine #11 scalpel blade on a handle #15 scalpel blade on a handle Curved hemostat 4 × 4 gauze squares Ribbon gauze, plain or iodoform Adhesive tape
INDICATIONS
PATIENT PREPARATION
Incision and drainage is indicated whenever a patient presents with a pilonidal abscess. Antibiotics alone are ineffective in treating a pilonidal abscess. Rarely, systemic signs and symptoms may ensue. There are reported cases of necrotizing fasciitis from neglected pilonidal sinus disease. Thus, it is preferable to treat pilonidal abscesses expeditiously with an incision and drainage procedure.
Explain the risks, benefits, and potential complications of the procedure to the patient and/or their representative. The postprocedure care should be explained as well. Document the discussion of the risks and benefits of the procedure. Obtain a signed informed consent for the procedure. The best visualization of the sacral region, particularly in obese patients, occurs with the use of a proctoscopic examination table, if available (Figure 109-3A). Place the patient prone on a gurney or on the proctoscopy table. Alternatively, place the patient in the lateral knee-chest position to expose the affected area (Figure 109-3B). Apply benzoin solution to the buttocks and allow it to dry. Apply adhesive tape to the buttocks and tape them open (Figure 109-4). Clean any dirt and debris from the skin overlying the abscess or cyst. Apply povidone iodine or chlorhexidine solution and allow it to dry. Shave the surrounding area, if the patient is hirsute, to aid in the application of the dressing after the procedure. Some authors advocate shaving the sacral region to prevent recurrence as well, although this has not been proven to be effective. A gown, face mask, and gloves (nonsterile) are recommended to be worn for this procedure.
CONTRAINDICATIONS The great majority of pilonidal abscesses may be drained in the Emergency Department. Patients occasionally present with fever, systemic signs and symptoms, and/or toxicity. They should be admitted to the hospital for parenteral antibiotics, incision and drainage, and observation. This is particularly true if the patient has diabetes or is immunocompromised. Consult a Surgeon to manage these patients. Extensive abscesses should be incised and drained in the Operating Room under general anesthesia. Patients who are asymptomatic do not require an incision and drainage and can be referred to a Surgeon for removal. The procedure should be conducted under general anesthesia in the Operating Room if adequate anesthesia cannot be obtained and pain limits the procedure.
EQUIPMENT • Gown, face mask, and gloves • Benzoin solution • Povidone iodine or chlorhexidine solution
ANESTHESIA Local anesthesia should be administered, recognizing that it is often difficult to obtain complete anesthesia by direct infiltration of an abscess. Local anesthetics are weak acids and are less effective in the acidic environment of an abscess. The skin over the abscess
FIGURE 109-3. Patient placement. A. Prone on a proctoscopy table. The patient may also be placed prone on a gurney. B. The lateral knee-chest position.
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FIGURE 109-4. Exposure of the abscess.
cavity usually becomes insensate, but anesthesia of the abscess cavity itself is not possible. The pain caused by injection of the local anesthetic solution is related to the rate that it is injected and the force necessary to inject it. Inject the local anesthetic solution slowly through a small-bore needle (25 or 27 gauge) as the needle is withdrawn through the dermis. The needle bore will create a passage through the subcutaneous tissue as it is inserted that enables the local anesthetic solution to be infiltrated slowly and with less discomfort. Hold the syringe horizontal in reference to the skin surface. Inject 3 to 4 mL of local anesthetic solution intradermally over the dome of the abscess (Figure 109-5). The skin will blanch if the injection is given properly. Do not inject the local anesthetic solution into the abscess cavity. The increased pressure within the cavity will cause more discomfort to the patient and may cause the local anesthetic solution or the abscess contents to be forcefully expelled if there is an opening in the skin. Additional anesthesia is accomplished by performing a field block (Figure 109-6).13 Inject local anesthetic solution subcutaneously around the periphery of the abscess (Figure 109-6A). Inject local anesthetic solution deep to the abscess in a fan-like pattern (Figure 109-6B). Systemic analgesia (i.e., procedural sedation) is usually required since it is quite difficult to obtain adequate anesthesia of an abscess locally. Refer to Chapter 129 for the complete details of procedural
FIGURE 109-5. Subcutaneous infiltration of local anesthetic solution. The needle and syringe are held parallel to the skin. The needle is inserted into the subcutaneous tissue overlying the pilonidal abscess. Infiltrate the local anesthetic solution as the needle is withdrawn. The skin should blanch (shaded area) if injected properly.
FIGURE 109-6. Field block anesthesia for a pilonidal abscess. A. Local anesthetic solution is infiltrated subcutaneously on all four sides of the abscess. B. The local anesthetic solution is infiltrated deep to the abscess cavity in a fan-like pattern.
sedation. Patient-administered nitrous oxide, with or without supplemental narcotic analgesics, is an alternative to procedural sedation. Refer to Chapter 128 for the complete details of nitrous oxide anesthesia. Obtain an additional signed informed consent for the procedural sedation or the nitrous oxide administration. The procedure should be conducted under general anesthesia in the Operating Room if adequate anesthesia cannot be obtained and pain limits the procedure.
TECHNIQUE Incise the skin over the area of maximum fluctuance with a scalpel blade. A 10% recurrence rate after drainage of chronic abscesses through a vertical incision lateral to the midline has been reported.14 This may be due to better healing of wounds that are off the midline. Thus, some authors and Colorectal Surgeons recommend that the incision for an acute abscess be off the midline if the abscess can be drained adequately through the incision (Figure 109-7A). Extend the incision the length of the abscess to allow for proper drainage. A full-thickness, thin ellipse of skin can be removed to prevent premature closure of the skin edges. Approximately 40% of pilonidal abscesses will be cured from simple incision and drainage alone.15 It is not necessary to perform more radical excision procedures in the Emergency Department. It is important that loculations be lysed and the area thoroughly drained to minimize recurrence. Several methods can be used to lyse adhesions within the cavity. A gloved finger may be used to bluntly break up the adhesions. Hemostats can be inserted and spread within the abscess cavity. A useful technique employs a 4 × 4 gauze square clamped in a hemostat and swirled inside the abscess cavity to break adhesions and remove debris (Figure 109-7B). This technique aids in removing hair and the infected lining of the cyst. Irrigate the abscess cavity with normal saline. Loosely pack the cavity with ribbon gauze. Packing the cavity too tightly may cause ischemia to the surrounding tissue, delays healing, and is uncomfortable for the patient. The purpose of the packing is to keep the skin edges from adhering before the cavity closes. Cover the incision with a simple bandage composed of gauze and adhesive tape. A thick layer of absorbent gauze will soak up any continued drainage.
CHAPTER 109: Pilonidal Abscess or Cyst Incision and Drainage
721
FIGURE 109-7. Incision and drainage of a pilonidal abscess. A. An incision is made lateral to the midline and overlying the abscess cavity. B. A hemostat with gauze clamped in the jaws is inserted into the abscess cavity and rotated to break loculations and remove debris.
AFTERCARE Antibiotics are generally unnecessary to treat a simple abscess when there is no cellulitis surrounding the wound.16 No data could be found on the optimal duration of antibiotic treatment if the overlying skin is cellulitic. The conventional 7 to 10 day course of antibiotics is probably adequate. Likewise, no studies could be found regarding treating patients with diabetes, cardiac valve disease, those who have hardware in their body, or those who are immunocompromised and have a pilonidal abscess. These patients are at risk for infectious complications and it is advised that they be treated with oral antibiotics. There is a disparity in the literature regarding the bacteriology of pilonidal abscesses. Staphylococcus aureus is the most commonly found bacteria and, surprisingly, Escherichia coli is rarely found.17 A report in children recovered primarily anaerobes from pilonidal cysts.18 Escherichia coli was the most common aerobe cultured from this series. In light of these conflicting results, and in the event that antibiotics are deemed necessary, coverage for skin flora as well as aerobes and gram-negative organisms would be advised. A combination of a first-generation cephalosporin or penicillinase-resistant penicillin along with metronidazole or clindamycin is recommended. Keep in mind the ever increasing rates of community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) infections. Consider prescribing clindamycin, doxycycline, or trimethoprim-sulfamethoxazole if CA-MRSA is a potential pathogen.19 Instruct the patient to change the gauze dressing as often as necessary to keep the outside of the dressing dry. The patient should return for follow-up in 48 hours for a wound check and removal of the packing. If the wound is large, or there is not a clear open tract for continued drainage, reinsert new packing upon follow-up. Incisions that remain open do not require repacking. Advise the patient to have the packing changed every 24 to 48 hours, depending upon the amount of drainage. Decrease the amount of packing each time to allow the wound to heal from the base outward. The patient should thoroughly wash the wound with soap and water in the shower or take a sitz bath each time the packing is removed. It is helpful to let the stream of shower water run inside the wound to aid in wound irrigation. After showering, the patient should dry the area thoroughly. Discontinue the packing once the wound is well granulated and there is no concern that the skin edges will adhere to each other. The patient must continue to clean the wound thoroughly every day until it is fully healed. Healing may take several weeks depending upon the size of the abscess cavity. Instruct the patient that they must return to the Emergency Department if they develop a fever, increased pain, or increased redness of the
skin surrounding the abscess. Patients often have pain in the first 2 to 3 days after the incision and drainage. This can be controlled with nonsteroidal anti-inflammatory drugs and supplemented with occasional narcotic analgesics. Inform the patient that incision and drainage in the acute care setting is not definitive treatment and that the condition may recur. Arrange for follow-up with a Surgeon who can provide wound care as well as definitive therapy if surgery is required. Definitive treatment of a chronic pilonidal abscess or sinus still remains controversial among Colorectal Surgeons. Options include wide excision with primary closure, wide excision with secondary closure, or marsupialization.2 Educate the patient about their role in the prevention of a recurrence. Recurrence may be prevented with meticulous hygiene and periodic shaving of the area.10,13 Instruct the patient on the methods for meticulous hygiene in the area, even after the wound has healed. Repeated trauma to the area should be avoided. This includes exercises such as sit-ups and leg lifts, and prolonged periods of sitting.
COMPLICATIONS Pilonidal disease may return, even with radical and extensive surgical excision procedures. Thus, recurrence is to be expected and the patient alerted of this possibility. Rarely, pilonidal lesions progress to necrotizing fasciitis. Proceed cautiously with patients who are diabetic or otherwise immunocompromised as they are at risk for widespread infections. Those with systemic signs and symptoms are best admitted for treatment. Necrotizing fasciitis is a surgical emergency and requires extensive operative debridement, systemic antibiotics, and intensive supportive care. Rarely, a nonhealing pilonidal infection may be a pilonidal sinus malignancy.20 Squamous cell carcinoma has been described to arise from chronic sinus tracts. This emphasizes the importance of follow-up for all patients with pilonidal sinus disease. Other complications include infection and tissue injury. The incision and drainage procedure can result in a subsequent cellulitis, endocarditis, fasciitis, meningitis, myositis, sacrococcygeal osteomyelitis, or septicemia. The sharp and blunt dissection can injure underlying or adjacent structures including blood vessels, the coccyx, muscles, nerves, and tendons.
SUMMARY Pilonidal disease is common in the young adult population and more prevalent in males. It is now widely accepted as being an acquired condition caused by hair that penetrates an irregular area of skin in
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the sacral area. Pits occur in the skin that in turn lead to cysts in the subcutaneous tissue. Patients may present with asymptomatic pits noted incidentally, as chronically draining sinuses, or an acute painful abscess. No treatment is necessary for asymptomatic patients. Nontender sinuses may be referred for surgical treatment. Abscesses should be drained expeditiously under adequate analgesia and anesthesia. Antibiotics are not indicated unless the patient has surrounding cellulitis or is immunocompromised. Recurrences are common and patients must be referred for follow-up with a Surgeon who can provide wound care as well as surgical treatment for chronic cases.
110
Perianal Abscess Incision and Drainage Maggie Ferng and Ryan C. Headley
INTRODUCTION Anorectal infections are common problems presenting to the Emergency Department. Understanding anorectal anatomy is essential to make a diagnosis, institute proper treatment, and anticipate complications. Failure to diagnose and treat an extensive abscess may be life threatening. It is imperative to obtain a surgical consultation if one is unsure of the extent of an abscess. Anorectal infections occur mostly in the third or fourth decade of life. Perianal abscesses are two to three times more common in men than women.1 Male predominance is even more pronounced in the pediatric population.2 In one series, all patients under 2 years of age were males, while 60% of the children greater than 2 years were males.2 The increased incidence of perianal infection in males may be related to androgen conversion in the anal glands.3 In infants, deep anal crypts are associated with perianal abscesses.4 Abscesses may completely resolve after a proper incision and drainage procedure. However, 50% recur or develop a chronic
epithelialized tract or fistula-in-ano. Abscesses and fistulas are different sequelae of the same process.5
ANATOMY AND PATHOPHYSIOLOGY Knowledge of the anatomy of the region is important to understand the pathophysiology of anorectal infections (Figures 110-1 & 110-2). Columnar epithelium transitions to squamous epithelium at the columns of Morgagni at the level of the dentate line. Semilunar folds of epithelium called anal valves connect the inferior borders of the anal columns. At the base of each anal valve is an anal crypt, into which opens the ducts of the anal glands. The anal glands secrete mucous to aid in the evacuation of feces. The anal glands are located in the space between the internal and external anal sphincter muscles. Most anorectal infections begin in this intersphincteric space due to blockage and resultant infection of the anal glands.6 The spread of an infection is determined by the anatomy of the anorectal region. There are five anatomic spaces into which an infection can spread (Figure 110-3).5 The perianal space is located at the area of the anal verge. The ischiorectal space, which is continuous with the perianal space, extends from the levator ani muscle to the perineum. The intersphincteric space lies between the internal and external anal sphincter muscles. It connects inferiorly with the perianal space and superiorly with the rectal wall. The supralevator (or pelvirectal) space is located superior to the levator ani muscle and is bounded superiorly by the peritoneum. The rectum forms its medial border and the pelvic wall forms the lateral boundary. The deep postanal space is located between the tip of the coccyx and the anus. It courses through the superficial external anal sphincter and the levator ani. The superficial postanal space lies posterior to the anal verge and is subcutaneous. The retrorectal space is high in the pelvis. It occupies the area between the distal rectum and the sacrum. Most anorectal infections begin in the intersphincteric space. Natural barriers are broken down by formation of an abscess and the infection can spread to contiguous spaces. Abscesses are classified according to their location. Perianal abscesses are common,
Column of Morgagni Dentate line Anal gland Anal crypt Anoderm
FIGURE 110-1. The anatomy of the anal canal.
Transitional zone
Anal canal
CHAPTER 110: Perianal Abscess Incision and Drainage
723
Longitudinal muscle Levator ani muscle
Valve of Houston
Circular muscle
Puborectalis muscle
Conjoined longitudinal muscle Internal anal sphincter muscle Column of Morgagni
Deep
Anal gland Superficial
External anal sphincter muscles
Subcutaneous
Corrugator cutis ani muscle
External hemorrhoidal plexus
FIGURE 110-2. The major supporting structures of the anal canal.
FIGURE 110-3. The anorectal spaces. A. Coronal section through the pelvis. B. Sagittal section through the pelvis.
ischiorectal abscesses occur less frequently, and supralevator abscesses are least common.7 Bilateral involvement may occur when an infection spreads circumferentially via the deep postanal space, resulting in a horseshoe abscess. Patients with anorectal abscesses present with buttock pain and swelling. There is, occasionally, spontaneous drainage from the abscess site. Symptoms depend upon the location of the abscess. Patients with perianal infections have anal pain that increases with defecation or sitting. Pain associated with deeper infections may be atypical. Patients with supralevator abscesses may have deep rectal pain, gluteal pain, dysuria, or other urinary symptoms. Erythema, swelling, and fluctuance are often present at the abscess site. The location of the swelling and fluctuance of a perianal abscess is at the anal verge. Ischiorectal space infections track farther from the anus onto the buttock. Supralevator and intersphincteric abscesses may have minimal or no external signs.8 The diagnosis of perianal cellulitis is highly suspect. These patients have either an anorectal abscess or Fournier’s Gangrene until proven otherwise. Patients with gluteal pain and a small amount of erythema in the perianal area have a deep-seated abscess until proven otherwise. A digital rectal examination is necessary as intersphincteric, deep postanal, and submucosal abscesses may be palpated but often cannot be appreciated on external examination. A superficial digital examination of the anal canal alone is inadequate for detection of some abscesses. The gloved finger must extend into the rectum seeking tenderness and a mass. Unfortunately, digital rectal exam may fail to detect some deep abscesses due to patient discomfort. If unable to obtain an adequate exam due to pain or if a deep abscess is suspected, obtain a CT scan of the pelvis with rectal and intravenous contrast. A fistula-in-ano represents the chronic phase of an unhealed perianal abscess. Fistulas may form due to persistent obstruction of the anal gland or inadequate drainage of an abscess. The tract eventually becomes epithelialized with glandular tissue. Fistulas may also form
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Posterior (curvilinear tract)
may safely undergo standard surgical drainage. Small perianal abscesses may be drained in the Emergency Department. Consult a General or Colorectal Surgeon for those patients with late-stage HIV disease. Infections are more likely to be extensive and anorectal sepsis is more common because these patients have poor wound healing.10
CONTRAINDICATIONS
Transverse anal line
Anterior (straight tract) FIGURE 110-4. Goodsall’s rule.
as a result of epithelialization by cells derived from the transitional zone of the anal canal and thus may be unrelated to persistent anal gland disease.9 Patients with a fistula-in-ano will often give a history of a previous abscess in the same area that was either drained surgically or spontaneously. Patients may complain of chronic drainage from the site or subacute pain. Physical examination of a fistula-in-ano reveals an external opening with scant drainage and visible surrounding granulation tissue. Digital rectal examination may reveal an indurated cordlike structure beneath the skin within the anal canal. The internal opening may be palpable along the dentate line. Pus may be expressed externally or from within the anus upon palpation of the fistulous tract. The greater the distance from the anus that the external opening is located, the more complex is the fistulous tract. Goodsall’s rule describes the likelihood of the location of fistulous tracts and the internal opening based upon the location of the external opening (Figure 110-4). Anterior external openings tend to communicate in a linear fashion with the internal opening in the anal canal. Fistulas with posterior external openings tend to communicate in a curvilinear fashion with the internal opening. Patients with multiple or recurrent fistulas require evaluation of the bowel for Crohn’s disease. This is particularly true if associated with chronic diarrhea or cramping, both of which suggests inflammatory bowel disease. Recurrent fistulas may be indicative of tuberculosis or a sexually transmitted disease such as lymphogranuloma venereum. It is imperative that these patients be referred to a Surgeon who is experienced in managing anorectal disease.
INDICATIONS Incision and drainage is the treatment for an anorectal abscess. Uncomplicated perianal abscesses and submucosal abscesses may be drained in the Emergency Department. Management of deeper or more extensive abscesses should be in consultation with a Surgeon. Use caution in draining abscesses. The ischiorectal space is quite large, particularly in the obese patient, and adequacy of drainage is not assured except under general anesthesia. It is not uncommon for an abscess to have a small erythematous and swollen area on the buttock overlying an extensive and deep abscess. Attempts at drainage in the Emergency Department may be inadequate. Perianal disease is commonly encountered in the HIV-infected patient. Complication rates were noted to be high in the past and a hands-off approach was espoused. However, more recent data suggest that those patients with a relatively preserved immune system
Most small, uncomplicated perianal and submucosal abscesses can be drained in the Emergency Department. A General or Colorectal Surgeon should drain all other types of anorectal abscesses. Caution is urged when an abscess is on the buttock for it may manifest an ischiorectal abscess. Patients with bleeding disorders, taking anticoagulants, or thrombocytopenia should be managed by a Surgeon. Consult a Surgeon if the infection is extensive or if the extent of the abscess cannot be determined. Surgical consultation is also necessary for patients with purulent drainage from inside the anus. Internal findings may indicate that the patient has an intersphincteric or a supralevator abscess; the full extent of which can be determined only under general anesthesia. The procedure should be conducted by a surgeon under general anesthesia in the Operating Room if adequate anesthesia cannot be obtained and pain limits the procedure. Patients with fever or toxicity should be admitted to the hospital for parenteral antibiotics, incision and drainage in the Operating Room, and observation. Anorectal infections occasionally progress to necrotizing fasciitis, a true surgical emergency. Physical examination findings in such cases may initially be minimal except for systemic signs or symptoms. Patients who are immunocompromised or with late-stage HIV infection should be referred to an experienced Surgeon due to the higher complication rate and increased risk of extensive infection. Chronically draining fistulas without an acute infection should be referred to a General or Colorectal Surgeon for care. Patients with purulent drainage from the anus, even if there is no significant tenderness, should be examined under general anesthesia as they may still have an internal abscess along with a fistulous tract.
EQUIPMENT • • • • • • • • • • • • • • • • • •
Gown, face mask, and gloves Povidone iodine or chlorhexidine solution 10 mL syringe 25 or 27 gauge needle, 2 in. long Local anesthetic solution with epinephrine, lidocaine, or bupivacaine #11 scalpel blade on a handle #15 scalpel blade on a handle Curved hemostat 4 × 4 gauze squares 10 to 16 French mushroom (de Pezzer) catheter, optional Adhesive tape Feminine napkin, optional Normal saline 18 gauge angiocatheter 20 mL syringe 2-0 nylon suture Needle driver Scissors
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725
FIGURE 110-5. Patient placement. A. Prone on a proctoscopy table. The patient may also be placed prone on a gurney. B. The lateral knee-chest position.
PATIENT PREPARATION Explain the risks, benefits, and potential complications of the procedure to the patient and/or their representative. The postprocedure care should be explained as well. Document the discussion of the risks and benefits of the procedure. Obtain an informed consent for the procedure. Wear a face mask, gown, and gloves for the entire procedure. The injection of local anesthetic solution can force abscess contents to shoot out. Incision of a tense abscess can also result in contamination. The best visualization of the sacral region, particularly in obese patients, occurs with the use of a proctoscopic examination table, if available (Figure 110-5A). Place the patient prone on a gurney or on the proctoscopy table. Alternatively, place the patient in the prone or lateral knee-chest position on a gurney or examination table to expose the affected area (Figure 110-5B). Apply benzoin solution to the buttocks and allow it to dry. Apply adhesive tape to the buttocks and tape them open (Figure 110-6). Clean any dirt and debris from the skin overlying the abscess or cyst. Apply povidone iodine or chlorhexidine solution and allow it to dry. Shave
FIGURE 110-6. Exposing the abscess.
the surrounding area, if the patient is hirsute, to aid in the application of the dressing after the procedure.
ANESTHESIA Local anesthesia should be administered, recognizing that it is often difficult to obtain complete anesthesia by direct infiltration of an abscess. Local anesthetics are weak acids and are less effective in the acidic environment of an abscess. The skin over the abscess cavity usually becomes insensate, but anesthesia of the abscess cavity itself is not possible. The pain caused by injection of the local anesthetic solution is related to the rate that the anesthetic is injected and the force necessary to inject it. Inject the local anesthetic solution slowly through a small-bore needle (25 or 27 gauge) as the needle is withdrawn through the dermis. The needle bore will create a passage through the subcutaneous tissue as it is inserted that enables the local anesthetic solution to be infiltrated slowly and with less discomfort. Hold the syringe horizontal in reference to the skin surface. Inject 3 to 4 mL of local anesthetic solution intradermally over the dome of the abscess (Figure 110-7). The skin will blanch if the injection is given properly. Do not inject the local anesthetic solution into the abscess cavity. The increased pressure within the cavity will cause more discomfort to the patient and may cause the solution to be forcefully expelled if there is an opening in the skin.
FIGURE 110-7. Subcutaneous infiltration of local anesthetic solution. The needle and syringe are held parallel to the skin. The needle is inserted into the subcutaneous tissue overlying the abscess. Infiltrate the local anesthetic solution as the needle is withdrawn. The skin should blanch (shaded area) if injected properly.
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A
B
Sebaceous cyst
FIGURE 110-8. Field block anesthesia. A. Local anesthetic solution is infiltrated subcutaneously on all four sides of the abscess. B. The local anesthetic solution is infiltrated deep to the abscess cavity in a fan-like pattern.
Additional anesthesia is accomplished by performing a field block (Figure 110-8). Inject local anesthetic solution subcutaneously around the periphery of the abscess (Figure 110-8A).11 Inject local anesthetic solution deep to the abscess in a fan-like pattern (Figure 110-8B). Systemic analgesia (i.e., procedural sedation) is usually required since it is difficult to obtain adequate anesthesia of an abscess locally. Refer to Chapter 129 regarding the details of procedural sedation. Self-administered nitrous oxide, with or without opioid supplementation, is an alternative. Refer to Chapter 128 regarding the details of nitrous oxide anesthesia. Obtain an additional informed consent for the procedural sedation or nitrous oxide procedure. The procedure should be conducted by a surgeon under general anesthesia in the Operating Room if adequate anesthesia cannot be obtained and pain limits the procedure.
TECHNIQUES INCISION AND DRAINAGE OF PERIANAL ABSCESSES Make a stab incision with a #11 scalpel blade in the skin overlying the area of fluctuance to decompress the abscess. Make the incision as close to the anus as possible so that if a fistula forms, its size will be limited. This maneuver will minimize the length of a fistulotomy, should it become necessary, in the future. Extend the incision with the #11 scalpel blade or a #15 scalpel blade in a full-thickness elliptical pattern along the length of the abscess cavity or the area of fluctuance (Figure 110-9A). Remove the ellipse
FIGURE 110-10. Drainage of perianal abscess employing a cruciate incision. A. The cruciate incision is made over the abscess. B. Excision of the skin flap edges. C. The final appearance.
FIGURE 110-9. Drainage of a perianal abscess. A. An elliptical incision is made in the skin. B. The ellipse of skin is removed to prevent premature closure of the skin edges.
of skin (Figure 110-9B). A full-thickness ellipse of skin is excised to prevent premature closure of the skin edges. Some prefer to make a cruciate incision over the abscess and excise the edges (Figure 110-10).5 Both of these techniques delay cutaneous healing while the abscess is decompressing and allow it to drain freely without the need for packing. A linear incision is acceptable instead of the above incisions, but is not recommended for a perianal abscess. The body location and excessive skin often result in premature closure before the cavity has healed. A linear incision requires repeated packing at 24 to 48 hour intervals to prevent premature closure. The area is difficult to access by the patient to pack the cavity. The pain of repeated packing often results in noncompliance. It is also difficult for the patient to wash out the cavity in the shower or bathtub. It is important that loculations be lysed and the area thoroughly drained to minimize recurrence. Several methods can be used to lyse adhesions within the abscess cavity. A gloved finger may be used to bluntly break up the adhesions. Hemostats can be inserted and spread within the cavity. A useful technique employs a gauze 4 × 4 square clamped in a hemostat and swirled inside the abscess cavity to break adhesions and remove debris. Irrigate the cavity with normal saline. It is not necessary to pack an incised and drained perianal abscess that has been incised by removing a full-thickness skin ellipse or a cruciate incision. Consider temporarily packing the abscess cavity in the Emergency Department to control any hemorrhage. Remove the packing before discharging the patient to reassess the need for further hemorrhage control. Cover the wound with a thick layer of absorbent gauze to soak up continued drainage. A feminine napkin may also be used to absorb drainage and obviates the need for taping the dressing in place.
CATHETER DRAINAGE OF PERIANAL ABSCESSES Another method used to drain perianal abscesses, and preferred by some Colorectal Surgeons, is catheter drainage. The mushroom or
CHAPTER 110: Perianal Abscess Incision and Drainage
727
FIGURE 110-11. Catheter drainage of an abscess. A. The mushroom (de Pezzer) catheter. B. A stab incision is made over the area of maximal fluctuance. C. Place the tip of the hemostat through the side hole to stretch the tip of the catheter. Insert the stretched catheter through the stab incision. D. Remove the hemostat to expand the head of the catheter so that it remains within the abscess cavity. E. The catheter is cut so that it protrudes 2 to 3 cm from the skin incision.
de Pezzer catheter has a tunnel through a solid mushroom-shaped tip (Figure 110-11A).12 Make a stab incision with a #11 scalpel blade over the anal side of the area of fluctuance (Figure 110-11B). Insert a hemostat into the abscess cavity. Open and close the jaws of the hemostat to lyse any adhesions and express the pus. Flush the abscess cavity with normal saline using an 18 gauge angiocatheter on a 20 mL syringe. Insert a 10 to 16 French latex mushroom catheter using a hemostat to stretch the tip so that it will fit through the incision. Place the tip of the hemostat through the hole in the mushroom catheter. With one hand holding the hemostat, use the other hand to pull on the tubing to stretch the mushroom tip and enable it to fit into the abscess cavity (Figure 110-11C). Insert the stretched mushroom tip into the abscess cavity (Figure 110-11C). Release the traction on the hemostat once the catheter tip is within the abscess cavity and the mushroom shape will be restored (Figure 110-11D). Remove the hemostat from the abscess cavity. Suture the catheter in place. Place a single simple interrupted stitch using 2-0 nylon adjacent to the stab incision. Leave both ends long, tie the suture knots, and do not cut the suture. Pass the needle through the catheter as it exits the skin incision. Tie the needle end of the suture to the tail end of the suture to secure the catheter. Cut off the excess suture. Cut the catheter so that it protrudes only 2 to 3 cm from the incision (Figure 110-11E). Apply a dressing of gauze squares or a feminine napkin. Many Colorectal Surgeons prefer the catheter method. On subsequent visits they can assess the wound for the presence of a fistula without removing the catheter. Hydrogen peroxide can be infused through the catheter. Bubbles seen escaping from an opening within the anal canal are diagnostic for a fistula. Hydrogen peroxide is also used to produce an ultrasound interface that facilitates the definition of a fistulous tract and the internal opening.5 The smaller stab incision takes less time to heal than the larger incision and drainage wound.
SUBMUCOSAL ABSCESSES The majority of submucosal abscesses may be drained in the Emergency Department. The procedure requires the use of an anoscope to visualize the abscess. Refer to Chapter 70 for the complete details regarding the use of an anoscope. Make a superficial stab incision in the abscess with a #11 scalpel blade. Gently insert a hemostat and lyse any adhesions. Remove a small ellipse of the mucosa to allow the abscess to drain. Arrange follow-up with a Colorectal Surgeon within 24 hours.
AFTERCARE Antibiotics are generally unnecessary to treat a simple abscess when there is no cellulitis surrounding the wound.13 No data could be found on the optimal duration of antibiotic treatment if the overlying skin is cellulitic. The conventional 7 to 10 day course of antibiotics is likely adequate. Likewise, there is no data in the literature regarding the treatment of patients with diabetes, cardiac valve disease, those who have hardware in their body, or those who are immunocompromised with antibiotics for a perianal abscess. These patients are at risk for infectious complications. It is advised that they be treated with antibiotics. Bacteriology of anorectal abscesses is polymicrobial, with coliforms and anaerobes predominating.14 Recommended antibiotics include an extended spectrum β-lactams, a second- or third-generation cephalosporin with metronidazole or clindamycin, or a newer fluoroquinolone with metronidazole or clindamycin. The patient may change the gauze dressing as often as necessary to keep the outside of the dressing dry. Instruct the patient to return for follow-up in 48 hours for removal of packing if placed and a wound check. The patient may begin sitz baths or showers 24 hours after the procedure. They should thoroughly clean the wound with soap and water at least once a day until the wound is fully healed. It
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is helpful to let the stream of shower water run inside the wound to aid in irrigation. Healing may take several weeks depending upon the size of the abscess. Additional measures to aid in healing and comfort include stool bulking agents and stool softeners. Pain can be controlled with nonsteroidal anti-inflammatory drugs supplemented with occasional narcotics analgesics. Advise the patient that the condition is likely to recur. They must be referred to a General or Colorectal Surgeon who is experienced in the management of anorectal infections. Inform the patient that they may require an operation to prevent future recurrences. Instruct the patient to immediately return to the Emergency Department if they develop a fever, increased pain or redness to the area, or a foul-smelling discharge.
COMPLICATIONS Perianal abscesses may recur or a fistula may form. Recurrence is more likely if the patient has had abscesses in the same location in the past. Occasionally, anorectal infections progress to necrotizing fasciitis. Patients with any systemic signs and symptoms require surgical consultation, hospital admission, parenteral antibiotics, and a drainage procedure. Complications associated with the incision and drainage procedure are rare. A linear incision or too small of an incision can result in premature skin closure, incomplete healing of the cavity, and recurrence. Too large of an incision can result in delayed healing. An overly aggressive incision can damage adjacent structures. Postprocedural bleeding is rare.
SUMMARY Anorectal infections are commonly seen in the Emergency Department. They are thought to be due to obstruction and subsequent infection of the anal glands that in turn form an abscess. Small perianal abscesses and submucosal abscesses can safely be drained in the Emergency Department. A digital rectal examination may aid in determining the extent of an abscess. A General or Colorectal Surgeon should manage patients with fever, signs of toxicity, evidence of a deep or extensive infection beyond the perianal area, or who are immunocompromised. Be alert that abscesses with maximum fluctuance on the buttock are more likely to have ischiorectal extension, are more complex, and greater in size. Perianal abscesses must be drained expeditiously to prevent their spread. Approximately 50% of anorectal abscesses will develop a fistulous tract. Patients require referral for follow-up with a General or Colorectal Surgeon who can provide wound care as well as manage chronic cases.
111
Sebaceous Cyst Incision and Drainage Carlos J. Roldan
INTRODUCTION Sebaceous cysts are common, present with a very benign evolution, may be located anywhere on the body, and frequently become infected. They are most commonly found on the face, neck, and trunk. Sebaceous cysts are usually asymptomatic unless they become infected. The Emergency Physician must be acquainted with the principles involved in treating infected sebaceous cysts, particularly if they are located on cosmetically important areas such as the face.
ANATOMY AND PATHOPHYSIOLOGY Sebaceous cysts are the result of obstruction of sebaceous gland ducts. They are freely mobile, slow growing, round shaped, painless, and located in the subcutaneous tissues. The cysts are made of a thin white capsule filled with a thick, cheesy, and keratinous material. Their size is variable and ranges from less than a quarter of an inch to more than 2 inches. These keratin-containing lesions are usually seen in young and middle-aged adults in relation to a pilosebaceous follicle.1 Sebaceous cysts may be present for many years before infection occurs. Physical examination often reveals a subcutaneous mass that is fluctuant and tender. The overlying skin may appear normal or erythematous. The initial treatment of choice of an infected sebaceous cyst is incision and drainage. The sebaceous material is too thick to allow for spontaneous drainage and it must be expressed. The sebaceous cyst will likely recur, however, unless the capsule of the cyst is removed. Patients may have the initial incision and drainage performed in the Emergency Department with follow-up at some later date to remove the cyst capsule. Alternatively, the cyst capsule may be removed at the time of the initial incision and drainage.
INDICATIONS Incision and drainage in the Emergency Department is indicated whenever a patient presents with a tender sebaceous cyst consistent with an abscess. The procedure will relieve the patient’s pain. Antibiotics without drainage are ineffective in treating abscesses.2 The vast majority of infected sebaceous cysts may be drained in the Emergency Department, clinic, or office setting. A noninfected sebaceous cyst may be removed electively and for cosmetic purposes in the clinic or office setting by a Primary Care Provider or a Surgeon.
CONTRAINDICATIONS There are no absolute contraindications to the incision and drainage or removal of an infected sebaceous cyst. Caution is advised in those patients with bleeding disorders, taking anticoagulants, or with thrombocytopenia. Incision and drainage is preferred if the overlying skin is cellulitic. The capsule can be removed at a later time. Extremely large abscesses or those in which adequate anesthesia is not possible should be managed in the Operating Room by a General Surgeon or Plastic Surgeon. The procedure should be conducted under general anesthesia in the Operating Room if adequate anesthesia cannot be obtained and pain limits the procedure. Refer patients with noninfected sebaceous cysts to their Primary Care Physician, a General Surgeon, or a Plastic Surgeon for removal.
EQUIPMENT • • • • • • • • • •
Gown, face mask, and gloves Povidone iodine or chlorhexidine solution 10 mL syringe 25 or 27 gauge needle, 2 in. long Local anesthetic solution, with or without epinephrine #11 scalpel blade on a handle #15 scalpel blade on a handle Curved hemostat Iris scissors Ribbon gauze, plain or iodinated
CHAPTER 111: Sebaceous Cyst Incision and Drainage
• • • • • •
2 × 2 gauze squares Adhesive tape Sterile saline Nylon sutures for skin closure, various sizes 3-0 Vicryl suture Needle driver
A
729
B
PATIENT PREPARATION Explain and document the risks, benefits, and potential complications of the procedure to the patient and/or their representative. The postprocedure care should be explained as well. Obtain an informed consent for the procedure. Obtain an additional informed consent for the procedural sedation or nitrous oxide procedure if it applies. Wear a face mask, gown, and gloves for the entire procedure. The injection of local anesthetic solution can force abscess contents to shoot out. Incision of a tense abscess can also result in contamination. Antibiotic resistance is a growing concern. The incision and drainage of a simple and noncomplicated skin abscess does not require antibiotic therapy.3,4 The incision and drainage procedure may release bacteria into the circulation. Consider the use of preprocedural intravenous antibiotics in those patients suspected or known to be immunocompromised, a history of prosthetic heart valve replacement, a history of artificial joint replacement, or signs of systemic toxicity. Clean any dirt and debris from the skin overlying the abscess or cyst. Apply povidone iodine or chlorhexidine solution and allow it to dry. Apply drapes to delineate a procedural field and absorb any material or blood that escapes from the abscess cavity.
ANESTHESIA Recognizing that it is often difficult to obtain, local anesthesia should be considered the first choice. Direct infiltration of the skin and soft tissues in a fan-like pattern surrounding an abscess or “field block” provides sufficient anesthesia to tolerate the procedure (Figures 111-1A & B).5 Local anesthetics are weak acids and less effective in the acidic environment of an abscess and should not be directly injected in the abscess cavity. The pain caused by injection of the local anesthetic solution is related to the rate that the anesthetic is injected and the force necessary to inject it. Inject the local anesthetic solution slowly through a small-bore needle (25 to 30 gauge) as the needle is withdrawn through the dermis. The needle bore will create a passage through the subcutaneous tissue as it is inserted that enables the local anesthetic solution to be infiltrated slowly and with less discomfort.
Sebaceous cyst
FIGURE 111-1. Field block anesthesia. A. Local anesthetic solution is infiltrated subcutaneously on all four sides of the infected sebaceous cyst. B. Local anesthetic solution is infiltrated deep to the infected sebaceous cyst in a fan-like pattern.
Hold the syringe horizontally in reference to the skin surface. Inject 3 to 4 mL of local anesthetic solution intradermally over the dome of the abscess (Figure 111-2). The skin will blanch if the injection is given properly. The increased pressure within the cavity will cause more discomfort to the patient and may cause the solution to be forcefully expelled if there is an opening in the skin therefore some practitioners prefer to skip this step. Alternative anesthesia could be accomplished with regional or individual nerve blocks when the abscess is located in an anatomical area of innervation. Systemic analgesia (i.e., procedural sedation) is strongly recommended in the pediatric population, it may occasionally be required as well in adults when a field anesthesia has suboptimal results. In rare occasions, the procedure should be conducted under general anesthesia in the Operating Room if adequate anesthesia cannot be obtained and pain limits the procedure.
TECHNIQUES INCISION AND DRAINAGE Make a stab incision with a #11 scalpel blade in the skin overlying the area of fluctuance (Figure 111-3A). The incision should be
FIGURE 111-2. Subcutaneous infiltration of local anesthetic solution. The needle and syringe are held parallel to the skin. The needle is inserted into the subcutaneous tissue overlying the infected sebaceous cyst. Infiltrate the local anesthetic solution as the needle is withdrawn. The skin should blanch (shaded area) if injected properly. A. Superior view. B. Lateral view.
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FIGURE 111-3. Incision and drainage of an infected sebaceous cyst. A. A straight incision to drain the abscess. B. An elliptical incision to drain the abscess. C. The wound is irrigated with sterile saline. Pockets of purulent material are opened with the hemostat. D. The wound is packed open.
parallel to any lines of tension to produce the least conspicuous scar, particularly in cosmetically important areas such as the face. Extend the incision the length of the fluctuant area with a #11 or #15 scalpel blade unless the abscess is in a cosmetically important area. A linear incision is adequate, although some advocate a cruciate incision (Figure 110-10). The cruciate incision results in greater scarring, however, and probably is not necessary. An elliptical incision can be performed in noncosmetically important areas (Figure 111-3B). The purpose of the elliptical incision is to remove a full thickness wedge of tissue so that the wound will remain open. Limit the length of the incision on cosmetically important areas to 3 to 4 mm. This is just large enough to drain the abscess. Express the pus and the sebaceous material. It is too thick to drain spontaneously. It is important that loculations be lysed and the area be thoroughly drained to minimize recurrence. Insert a hemostat and spread the jaws within the cavity (Figure 111-3C). Useful technique employs gauze clamped in the jaws of a hemostat and swirled inside the abscess cavity to break adhesions and remove debris. Irrigate the cavity with normal saline (Figure 111-3C). Loosely pack the wound cavity with ribbon gauze or gauze squares to prevent the skin edges from closing prematurely if a linear incision was made (Figure 111-3D). Cruciate and elliptical incisions do not require packing of the wound. Cover the wound with a bulky gauze dressing to soak up continued drainage.
INCISION AND DRAINAGE WITH PRIMARY CYST REMOVAL The entire sebaceous cyst, including the capsule, can be removed at the time of the incision and drainage with a simplified technique.6 Make an incision in the skin overlying the center of the sebaceous cyst. Extend the incision to be slightly longer than the diameter of the sebaceous cyst. Do not cut into the dermis or subcutaneous tissues. Sharply dissect the sebaceous cyst free of the surrounding
subcutaneous tissues with an iris scissors. The delineation between the thin, shiny, white capsule and the surrounding tissues is very obvious. Do not puncture the capsule of the sebaceous cyst. Doing so and spilling some of the contents sets up a nidus for subsequent infection or reformation of the sebaceous cyst. Start at both ends of the incision and free the cyst circumferentially. Once the sides of the cyst are free from the surrounding adipose tissue, gently grasp the top of the cyst with a hemostat or forceps and gently elevate it. Dissect the inferior border of the cyst free until it can be removed. Irrigate the wound with at least 200 mL of normal saline solution. Allow the cavity to heal by granulation. Alternatively, close the pocket with 3-0 Vicryl deep sutures and approximate the skin edges with nylon sutures. The cyst capsule can often rupture when attempting to remove it intact. If this occurs, express the contents as if incising and draining an abscess. Gently flush the cyst cavity with normal saline. Grasp the shiny, cut edges of the capsule with a hemostat. Gently elevate the cyst capsule edges and dissect the complete cyst capsule free from the surrounding adipose tissue. Irrigate the wound with at least 200 mL of normal saline solution. Allow the cavity to heal by granulation. Alternatively, close the pocket with 3-0 Vicryl deep sutures and approximate the skin edges with nylon sutures. Submit the complete cyst and capsule or the ruptured capsule for pathologic diagnosis in a sterile container. Several pathologic conditions can mimic a sebaceous cyst. This includes adenomas, adenocarcinomas, dermoids in children, and melanomas. Preauricular tender masses can be parotid gland tumors. This technique results in fewer days to heal, less pain for the patient, and less scarring than with incision and drainage alone.6 This was not a blinded study and no other studies could be found to verify their results. The researchers noted that primary resection (average of 50 minutes) takes longer than simple incision and drainage (average of 10 minutes). This may limit its use in the Emergency Department.
CHAPTER 112: Hemorrhage Control
AFTERCARE Antibiotics are generally unnecessary to treat a simple abscess unless there is cellulitis of the skin surrounding the wound.2 No data could be found regarding patients with an abscess who are diabetic, have cardiac valve disease, who have hardware in their body, or who are immunocompromised. These patients are at risk for infectious complications. It is advised to cover these patients with antibiotics. Likewise, there is no data on the optimal duration of antibiotic treatment. The conventional 7 to 10 day course of antibiotic coverage is probably adequate. Bacteriology of cutaneous abscesses remote from the rectum usually show aerobic skin flora, with Staphylococcus and Streptococcus being the most common etiologies.4 Antibiotics recommended are a first-generation cephalosporin, a penicillinase-resistant penicillin, or a newer fluoroquinolone. Prescribe clindamycin, doxycycline, or trimethoprim-sulfamethoxazole if methicillin-resistant Staphylococcus aureus is suspected as the etiology.7 Instruct the patient to change the gauze dressing as often as necessary to keep the outside of the dressing dry. Patients should have scheduled follow-up in 48 hours for a wound check and removal of the packing. The packing should be removed in 24 hours if the wound is on the face. If the wound is large, reinsert the packing upon follow-up. Incisions that remain open or that have an elliptical or cruciate incision do not require packing. Advise the patient to change the packing every 24 to 48 hours, depending on the amount of drainage. Decrease the amount of packing each time to allow the wound to heal from the base outward. The patient should thoroughly wash the wound with soap and water in the shower each time the packing is removed. It is helpful to let the stream of shower water run inside the wound to aid in wound irrigation. Discontinue the packing once the wound is well granulated and there is no concern that the skin edges will adhere to each other. The patient must continue to clean the wound thoroughly every day until it is fully healed. Healing may take one to several weeks depending upon the size of the abscess cavity, the patient’s age, and any comorbidities. Instruct the patient to return to the Emergency Department immediately if they develop a fever, increased pain, or worsening redness of the skin surrounding the abscess. Pain relief can be provided with nonsteroidal anti-inflammatory drugs. Occasionally, narcotic analgesics may be required in the first 24 hours after the procedure. Inform the patient that incision and drainage in the acute care setting is not definitive treatment and that the condition is likely to recur unless the cyst is removed. Refer the patient to a physician who can provide wound care as well as remove the cyst capsule.
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abscess. Most cutaneous abscesses can be drained in the Emergency Department. Consult a Surgeon for those patients with large abscesses who require drainage in the Operating Room. Patients with signs of fever or toxicity should be admitted for parenteral antibiotics, incision and drainage, and observation. Refer patients to a physician who can provide wound care as well as definitive excision of the sebaceous cyst.
112
Hemorrhage Control Christopher Freeman and Eric F. Reichman
INTRODUCTION Control of external hemorrhage from an injury is a priority of basic first aid, beginning with the first responder in the prehospital setting and continuing with Emergency and Trauma Physicians in the resuscitation suite. Bleeding from extremity wounds is common. Most extremity bleeding is a minor inconvenience for the busy Emergency Physician in the crowded Emergency Department, prolonging wound closure and complicating wound healing. However, major exsanguinating extremity hemorrhage can be a life threat. Hemorrhage from extremity injuries was a leading cause of death in the Vietnam War and Operation Desert Storm.1,2 Hemorrhage remained the leading cause of death in Operation Iraqi Freedom and Operation Enduring Freedom; however, torso hemorrhage was the leading cause of death.3 Methods for rapid and effective control of bleeding are essential in managing traumatic injuries and optimizing wound management.
ANATOMY AND PATHOPHYSIOLOGY
Sebaceous cyst infections may spread if the wound is inadequately drained. Attention must be paid to underlying anatomical structures, such as cranial nerve VII, when draining facial abscesses to avoid complications caused by inadvertently incising these structures. Incomplete removal of the cyst wall or spillage of the cyst contents sets up a nidus for future infection and/or recurrence of the sebaceous cyst. A linear incision or too small of an incision can result in premature skin closure, incomplete healing of the cavity, and recurrence. Too large of an incision can result in delayed healing and significant scarring. Postprocedural bleeding is rare.
Hemostasis is the first biological response to injury.4–6 Hemostatic platelet plugs form at the ends of transected vessels within seconds of traumatic disruption of the skin. Fibrin fibers gather about the platelet plug within minutes. This fibrin mesh becomes part of an early matrix that initiates wound healing.4 Hemostasis is also the first priority in wound management for the Emergency Physician caring for traumatic wounds. Control of bleeding is necessary to establish hemodynamic stability and prevent further blood loss. Hemostasis is the first step in preparing for wound closure. Inadequate hemostasis with hematoma formation impairs wound healing, increases the risk of wound infection, leads to tissue ischemia, and results in hypertrophic scars.7,8 Large hematomas may cause delayed wound dehiscence. Bleeding from wounds may be superficial or deep. Superficial wounds, such as abrasions, avulsions, or simple lacerations involve damage to the epidermis, dermis, and subcutaneous tissue. Bleeding from most superficial wounds is predominantly from capillaries, small veins, or arterioles. Wounds deep to the fascia involve larger vessels and are typical of deep puncture or stab wounds, gunshot wounds, or major crush injuries. The approach to the bleeding wound will depend upon the nature of bleeding (e.g., large vessel vs. small, discrete source vs. diffuse), the site of injury, and its association with other major organ injury.
SUMMARY
INDICATIONS
Infected sebaceous cysts are commonly seen in the Emergency Department. They are thought to be due to blockage of the ducts of sebaceous glands that subsequently become infected and form an
The immediate control of excessive bleeding is always a priority and should occur during the first contact with the patient. All bleeding must be controlled. Exsanguinating hemorrhage must be
COMPLICATIONS
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immediately controlled. All other bleeding can wait until the ABC’s and life-threats are addressed. The timing and selection of specific measures to isolate and treat the bleeding source will depend upon the management priorities of each patient. A simple compressive dressing or tourniquet may be used as a first-line measure to control bleeding in a multiple trauma patient. Measures that are more definitive may be taken early to identify and treat the specific injury if it is isolated.
CONTRAINDICATIONS There are no absolute contraindications to any particular technique to control bleeding. The Emergency Physician should choose the technique best suited to the individual situation. An impressive wound should not distract or divert attention away from other injuries that may be less dramatic but more immediate life threats. The simplest and most effective techniques should be used to control hemorrhage when faced with multiple injuries.
EQUIPMENT Pressure Control • Blood pressure cuff • Sterile 4 × 4 gauze pads • Elastic bandage Wound Manipulation • Hemostats • Needle driver • Assorted suture • Scissors • Sterile saline • 20 mL syringes • 10 mL syringes • 18 gauge needles • 27 gauge needles Anesthetics • Lidocaine, with and without epinephrine • Bupivacaine, with and without epinephrine • 18 gauge needles • 27 gauge needles • 10 mL syringes Wound Cautery • Silver nitrate (AgNO3) • Electrocautery unit • Monsel’s solution (20% ferric subsulfate solution) • Drysol (30% aluminum chloride solution) Vasoconstrictors • Epinephrine, 1:1000 • Cocaine, 1% to 4% • Tetracaine, epinephrine, and cocaine (TEC) solution Topical Hemostatic Agents • Gelfoam • Surgicel • Cellulose
• • • • •
Dry gelatin Thrombin Microfibrillar collagen Cyanoacrylate Various agents as listed in the techniques section
Miscellaneous Supplies • Povidone iodine or chlorhexidine solution • Penrose drain • Finger tourniquet • Hemoclips • Hemoclip applicator • Bone wax • Raney scalp clips and applier
PATIENT PREPARATION Control of hemorrhage is the priority. Attention to wound preparation should not delay definitive action to control bleeding. Obtain intravenous access and a type and crossmatch for blood products in any patient with active bleeding and hemodynamic compromise while applying direct pressure to the bleeding site. Explain the procedures to the patient while preparing for and performing the procedures. A local anesthetic can be administered prior to significant wound manipulation if the injury is minor and the patient is stable. Contaminated wounds should be irrigated free of foreign bodies and debris and the surrounding area cleaned with an antiseptic solution (i.e., povidone iodine or chlorhexidine). Refer to Chapter 92 for the complete details of wound cleansing and preparation.
TECHNIQUES DIRECT PRESSURE The quickest and easiest method to stop bleeding is the application of direct pressure to the bleeding site.9–11 Poor lighting may prevent the exposure and visualization necessary to identify discrete bleeding sites in the prehospital setting. A compressive dressing may be the best option to control bleeding. Unfortunately, most compressive bandages apply too little pressure over too wide an area and act more like a sponge than a pressure dressing. Significant blood loss can be hidden within a bulky dressing. Explore a bleeding wound as soon as lighting is sufficient and circumstances allow. Even brisk bleeding frequently has a few discrete sources that can be easily managed once identified. Direct pressure over bleeding vessels allows time for a platelet plug to form and gives a chance for the body’s natural mechanisms of hemostasis to take place. Apply pressure over arterial wounds for 10 to 15 minutes to control most bleeding. Apply pressure to a proximal artery to impede arterial inflow and control, or slow, the bleeding when wound exploration is not practical.12,13
TOURNIQUETS The use of tourniquets for extremity hemorrhage has received a great deal of attention throughout history. In reality, tourniquets are seldom necessary to control hemorrhage, even in major crush wounds, amputations, and in wilderness settings.14 Direct pressure is more effective and causes less tissue ischemia. Tourniquets may be required to control bleeding and free rescue personnel to attend to other concerns if there is significant bleeding in a mass
CHAPTER 112: Hemorrhage Control
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FIGURE 112-1. Control of the bleeding vessel that is visualized. A. Clamp the cut end of the vessel with a hemostat. B. Wrap a suture ligature about the base of the vessel. C. Tie and secure the suture around the base of the bleeding vessel.
casualty disaster. Tourniquets should be used as a last resort when other methods fail and the patient’s life is in jeopardy.12,14 Some of the currently available tourniquets include the Combat Application Tourniquet (Composite Resources, Rock Hill, SC), the Special Operations Forces Tactical Tourniquet (Tactical Medical Solutions, Anderson, SC), and the Emergency and Military Tourniquet (Delfi Medical, Vancouver, Canada). There is no definitive time period to safely apply a tourniquet. There is a risk of limb ischemia and eventual limb loss any time a tourniquet is used. It is generally accepted that 2 hours is a safe time period.38–40 Beyond this time, it is believed that permanent muscular or neurologic injury may occur. However, a tourniquet has been safely applied for up to 6 hours without permanent complications.40–42 Use the minimal tourniquet pressure necessary to maintain hemostasis. Release the tourniquet periodically and reassess the extremity. It is best to limit the use of a tourniquet for the minimum time required to temporarily be lifesaving and until definitive care can be received.
BALLOON CATHETERS
Familiarity with the vascular supply to the extremities will help the Emergency Physician anticipate major arterial injuries and look for likely bleeding sources. Whenever a transected vessel is seen, the other end should be searched for. A retracted artery in spasm will likely bleed later and should be actively sought and ligated. Bleeding vessels that can be visualized should be ligated with suture (Figure 112-1). Grasp the cut end of the bleeding vessel with a hemostat (Figure 112-1A). Pass an appropriate sized suture around the vessel (Figure 112-1B). Use absorbable sutures that do not lose their tensile strength too soon (e.g., Vicryl, Monocryl, and PDS). Tie and secure the suture around the base of the bleeding vessel (Figure 112-1C). Gently release the hemostat from the blood vessel. Cut blood vessels, especially arteries and arterioles, often retract into the tissue and are difficult to visualize. A suture can be used to control the bleeding (Figure 112-2). Place a figure-of-eight stitch (Figure 112-2A) or a pursestring stitch (Figure 112-2B) to encompass the blood vessel. These sutures are simple, quick, and easy to place.
Physicians have been using balloon catheters to tamponade exsanguinating bleeding from deep wounds or wound tracks. These devices were not specifically designed for this purpose, but used as an improvised technique to temporarily tamponade the hemorrhage. Devices used have included Fogarty catheters, Foley catheters, and Sengstaken–Blakemore tubes. These devices are blindly placed in the wound and inflated to tamponade bleeding from vascular and solid organ injuries. Tourniquets specific for deep wound hemorrhage are being developed. These devices may be used when conventional external methods (e.g., clotting agents, direct pressure, and tourniquets) do not control the hemorrhage. This group of devices are inserted into the wound or wound track and inflated to tamponade the bleeding. One of these devices is the Tournicath (CardioCommand, Tampa, FL). These devices have not yet been fully evaluated for use in the prehospital setting or in the Emergency Department.
SUTURE LIGATION Thoroughly inspect briskly bleeding wounds. Place a blood pressure cuff proximally and inflate it until a dry bloodless field is obtained. Large vessel bleeding will first become apparent as the cuff pressure is slowly dropped. Large and intermediate-sized vessels will need to be ligated or oversewn for effective control.
FIGURE 112-2. Control of a bleeding vessel deep or embedded in tissue. A. The figure-of-eight stitch. B. The pursestring stitch. Note that both of these stitches are not tied tightly for the sake of clarity. In real use, both of these stitches will be tied tightly to seal the bleeding vessel.
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FIGURE 112-3. The battery-powered electrocautery device.
CAUTERY Place a blood pressure cuff proximally and inflate it until a dry bloodless field is obtained. Small bleeding vessels will be identified as the inflated blood pressure cuff pressure is gradually reduced. The most likely source of significant bleeding from small vessels are from veins and dermal arterioles. Venous bleeding usually stops with direct pressure alone. Dermal arterioles tend to resist direct pressure and cause persistent oozing from the wound edges. Blood vessels are best identified by picking up the wound edge and inspecting the dermis. These bleeding vessels can be effectively treated with electrocautery or chemical cauterization. Electrocautery is surprisingly easy and effective against aggressive bleeding from small vessels less than 2 mm in diameter.9 Handheld battery-driven electrocautery units use a heated electrode to deliver a thermal burn to the tissue and char the ends of vessels (Figure 112-3). They are simple to use, inexpensive, and stocked in most Emergency Departments. More versatile electrosurgical units, such as the Bovie and Hyfrecator, are extremely effective coagulators.15 Unfortunately, they are not routinely available in most Emergency Departments. Chemical cauterization with silver nitrate (AgNO3) is an effective alternative. The silver nitrate is a dark material that is provided on the end of a wooden applicator stick, resembling a large matchstick (Figure 112-4). Rub the silver nitrate over the cut end of the vessel.
FIGURE 112-4. The silver nitrate (AgNO3) applicator.
It forms an insoluble precipitate with tissue protein to form an artificial clot or an eschar that occludes the vessel lumen. Silver nitrate cannot be used on briskly bleeding vessels as it will coagulate the blood and not the vessel. The cut vessel must not be bleeding or just oozing for silver nitrate to coagulate the tissue. The reduced silver nitrate salts stain the tissue it contacts black. Most of the black silver salts are resorbed by the body over several weeks. There is the possibility of permanent staining or tattooing of the skin. Thus, do not use silver nitrate on light skin individuals or close to the skin surface in cosmetically sensitive areas. Minimize tissue contact with silver nitrate to prevent damage to the underlying tissue. Two topical solutions can be used for chemical cauterization. Monsel’s solution is a 20% ferric subsulfate solution that is thick and dark brown to black in color. Like silver nitrate, it can permanently stain or tattoo the skin. Drysol solution is a 30% aluminum chloride solution that is colorless. It will not stain or tattoo the skin. Drysol solution may not be as effective as Monsol’s solution for cauterization. Both of these solutions are applied to a relatively dry or slightly moist area with a cotton-tipped applicator. Briefly apply the electrocautery or chemical cautery directly to the bleeding source. Neither technique will work well unless the field is dry. This can be achieved with the use of suction, the wound can be dabbed dry with gauze or cotton-tipped applicators, or external pressure. More liberal use to the surrounding tissue will leave unnecessary damage and impair wound healing. Overzealous use of electrocautery and chemical cautery can cause unnecessary tissue necrosis and increase the risk of infection.
VASOCONSTRICTORS Smaller bleeding vessels will usually constrict and eventually stop on their own once major vessels have been treated. If not, the use of local vasoconstrictors and topical hemostatic agents is effective.16 Epinephrine is a convenient and effective vasoconstrictor.17 It can be injected into the wound edges with local anesthetic or placed directly into the wound. Epinephrine and other vasoconstrictors should not be used in a finger, toe, ear, nose, or penis where ischemia may cause tissue loss. Topical vasoconstrictors should be used with diligent attention to the total dose administered to avoid systemic side effects such as hypertension, tachycardia, and seizures. Commonly available local anesthetic solutions containing epinephrine that are available in the Emergency Department include lidocaine and bupivacaine. Inject 1 to 2 mL of local anesthetic solution containing epinephrine into the tissue surrounding the bleeding vessel, cover the wound with saline-moistened gauze, and apply external pressure for 2 to 4 minutes. Use caution and aspirate prior to the injection to ensure that the solution is not being injected intravascularly. Alternatively, spray 1 to 2 mL of 1:1000 epinephrine or epinephrine containing local anesthetic solution over the wound surface with a 25 gauge needle, cover the wound with a sterile saline-moistened gauze, and apply external pressure for 2 to 4 minutes.18 A more dilute epinephrine solution can be used in larger wounds to minimize potential side effects. Solutions as dilute as 1:100,000 to 1:1,000,000 are used to control the brisk bleeding that accompanies tangential burn wound excision and graft donor sites.19 Topical cocaine (1% to 4%) is a potent vasoconstrictor commonly used on mucous membranes. Combinations of 0.5% tetracaine, 1:2000 epinephrine (adrenalin), and 11.8% cocaine (TEC) are used for topical anesthesia and hemostasis in pediatric wounds.20 Apply 1 to 2 mL of these solutions directly into the wound followed by an occlusive dressing.
CHAPTER 112: Hemorrhage Control
TOPICAL HEMOSTATIC AGENTS This group of agents has seen most of the recent innovation in hemorrhage control. Most of these agents were originally developed for operative hemostasis. There use has expanded into the Emergency Department. More and more hemostatic agents are being developed for hemorrhage control outside the operating room or for lifethreatening hemorrhage when other standard agents have failed. Topical hemostatic agents used in the Emergency Department include cellulose, dry gelatin, thrombin, microfibrillar collagen, cyanoacrylate, inorganic, and polysaccharide-based agents. Injudicious reliance on hemostatic agents should not replace a methodical approach to wound care and a meticulous search for bleeding vessels. Oxidized cellulose (i.e., Surgicel) or dry gelatin (e.g., Gelfoam, Surgifoam) based agents can be used to provide hemostasis in wounds when there is diffuse oozing, especially where a small amount of blood impedes wound closure and jeopardizes a cosmetic outcome. These agents provide a matrix for platelet deposition and aid hemostasis.7,16 Troublesome wounds can be treated with these agents and covered with a pressure dressing. After a few minutes, the dry field can be approximated with sutures. Another option is to simply leave the hemostatic agent in the wound, close the wound, and apply a pressure dressing. These techniques will be effective for many wounds. These substances are not free of complications. Absorbable gelatin in a wound can produce excessive granulation tissue and fibrosis. Cellulose can cause a foreign body reaction. In cases where the bleeding persists, topical thrombin or microfibrillar collagen (e.g., Avitene, Instat, Helistat) may be useful hemostatic agents in these problematic cases.16 Apply topical thrombin in powder form, or diluted with saline and sprayed on the wound. Concentrations of 100 units/mL are usually effective. Concentrations of 1000 to 2000 units/mL can be used if the bleeding is severe. Alternatively, microfibrillar collagen can be used to encourage platelet aggregation. Both thrombin and microfibrillar collagen are expensive and are not usually supplied outside the Operating Room. Their use should be restricted to the unusual patient with a coagulopathy or severe bleeding unresponsive to other measures. Cyanoacrylate tissue adhesives are commonly used in the Emergency Department for wound closure. It is also a helpful adjuvant for hemostasis. In simple wounds where cyanoacrylate is used for wound closure, it forms an occlusive dressing that provides hemostasis. There is little human data demonstrating the hemostatic activity of cyanoacrylate. It has been shown to promote clot formation, decrease bleeding time, and decrease rebleeding in porcine models for epistaxis and femoral arterial injury.21,22 It is important to note that cyanoacrylate works best in a dry, bloodless field that can be obtained by a combination of direct pressure, irrigation, and temporary tourniquet use. Hemostasis was achieved in a porcine arterial hemorrhage model in 90% of the animals after temporary tourniquet placement, irrigation, and cyanoacrylate application via spray.22 Given the occlusive nature of cyanoacrylate, the wound can remain uncovered after its application, allowing for easier recognition of rebleeding if it occurs. A relatively new area in topical hemostasis is the management of life-threatening bleeding in the nonoperative setting. This has focused on hemostatic dressing and agents, which when applied, lead to rapid hemorrhage control. These products are placed in the wound, covered with gauze, and pressure is then applied. More definitive management can be planned after hemostasis is achieved. These agents fit into two broad categories, inorganic and polysaccharide-based hemostatic agents. The inorganic hemostatic agents include Quickclot (Z-Medica, Wallingford, CT) and Woundstat (TraumaCure, Bethesda, MD).
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Quickclot is a zeolite powder that adsorbs water and produces an exothermic reaction, releasing heat into the surrounding tissue.23 The exact composition is proprietary, but the company states that it contains no biological or botanical substances. It is available as a loose powder and granular beads in a meshwork fabric. While zeolite provided hemostasis in some animal models, there were mixed outcomes and the exothermic reaction can cause temperatures in excess of 212°F or 100°C, leading to thermal tissue injury.24,25 A new formulation now produces heat of approximately 105°F or 40.5°C to reduce the potential for thermal injury. This may limit Quickclot’s clinical use. Woundstat is a smectite nonmetallic mineral that is composed of sodium, calcium, and aluminum silicates. It adsorbs water without producing an exothermic reaction, concentrates blood products, and promotes hemostasis. It is available as granular powder that is packed into wounds. Woundstat use demonstrated decreased blood loss and improved survival compared to Quickclot in animal studies.26,27 The polysaccharide-based agents are classified as N-acetylglucosamines containing glycosaminoglycans and microporous polysaccharide hemispheres. The data supporting the use of these agents are limited, mostly derived from animal studies with multiple differing models making direct comparison between the products difficult. N-Acetylglucosamine glycosaminoglycans are a complex polysaccharide derived from marine microalgae or crustacean shells in the form of chitin or chitosan.24 These agents are thought to provide hemostasis through multiple mechanisms including tissue adhesion, attraction of circulating red blood cells, and vasospasm.28 N-Acetylglucosamine-based agents include Hemcon and ChitoFlex (Hemcon Medical Technologies, Portland OR), Celox (SAM Medical Products, Portland OR), and Modified Rapid deployment Hemostat (Marine Polymer Technologies, Danvers, MA). Hemcon is available as a coated bandage. Celox is available as granules, granules in a disposable bag, coated flexible gauze, and in a plunger for deep application. Modified Rapid deployment Hemostat is available as a coated gauze. Hemcon, one of the best studied agents, has demonstrated mixed results in animal studies but has favorable reports from its limited use with the United States military.29 A limited study of 10 trauma patients with intraabdominal injuries achieved hemostasis in 90% of the patients with Modified Rapid deployment Hemostat.30 Microporous polysaccharide hemispheres are derived from potato starch. The agent in this class is Traumadex (Medafor, Minneapolis, MN). Traumadex functions as a sponge, dehydrating the blood, concentrating the blood constituents, and promoting clot formation.24 It is available as a powder and an impregnated bandage. Similar products are available as a spray and plunger for deep application. It performed better than a standard dressing in a swine model of lethal hemorrhage, but worse than both Hemcon and Quickclot.31 Dry Fibrin Sealant Dressing (DFSD) is composed of clotting proteins purified from donated blood and plasma. The DFSD is a multilayered dressing composed of fibrin, calcium chloride, thrombin, and an absorbable mesh. The dressing combines with blood to become activated and adhere to the tissues. These DFSD’s require special handling and are very expensive, both of which will limit its use in the Emergency Department. The limited human evidence, case reports, and small studies make comparison of the various hemostatic agents difficult. The application of these agents is simple. Determining which of these agents to use is difficult. It is likely that one or more of these products will become a useful adjunct in topical hemostasis in the early phase of trauma management in the Emergency Department. The Defense Advance Research Projects Agency (DARPA) is looking into novel methods of hemorrhage control for the battlefield.
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They are in the process of developing a wound dressing with an embedded ultrasound device that would be tuned at the resonant frequency of blood. The ultrasound would emit and focus highpower energy toward the bleeding site and stimulate coagulation. If practical and effective, its use can be expanded to the prehospital environment and the Emergency Department.
WOUND CLOSURE VERSUS PACKING The wound can be approximated, a pressure dressing applied, and the limb elevated when oozing cannot be controlled by any other method. Alternatively, the wound can be packed with salinemoistened gauze until better hemostasis is achieved. Obtain a coagulation profile in anyone with persistent diffuse bleeding. If a correctable coagulopathy is identified, the wound can be approximated after the coagulopathy is corrected.
ALTERNATIVE TECHNIQUES The general techniques discussed above apply to bleeding from most sites. There are a number of techniques applicable to specific anatomic sites.
THE HAND Hand injuries pose special problems. Strict hemostasis is necessary to examine the wound and identify any associated damage to tendons, nerves, and joint capsules. A tourniquet can be placed to exsanguinate the extremity and facilitate wound inspection. Elevate the limb and wrap it with an elastic bandage to “milk” the venous return toward the heart. Apply a blood pressure cuff to the forearm or arm and inflate it above the systolic blood pressure. This prevents arterial inflow while minimizing the backflow from venous engorgement to reliably provide a bloodless field. A digital tourniquet may expedite the examination if the injury is confined to a single digit.32,33 A number of methods are effective. A Penrose drain can be wrapped about the base of the finger and secured with a hemostat (Figures 104-3 & 112-5A). Mark a 0.25 in. Penrose drain with two lines placed 26 mm apart. Stretch the Penrose drain about the base of an average adult finger until the lines meet. Clamp the Penrose drain with a hemostat to generate a sufficient but safe pressure.32 An alternative is to use a surgical glove with the fingertip cut off and rolled down to leave a tight band at the base of the digit (Figures 104-4 & 112-5B). Use a glove size larger than what would typically fit the patient for general use to avoid generating excessive pressure.32 Disposable, preformed, rubber digital tourniquets are commercially available (Figures 104-5, 104-6, and 112-5C).34 Refer to Chapter 104 for a more complete discussion of digital tourniquets. These tourniquets exsanguinate the digit and prevent arterial inflow. Tourniquets should be applied for no more than 20 to 30 minutes to avoid injury to the digital nerves. Hemostasis is important but should not be pursued without regard to the surrounding tissues. Hand wounds should not be explored or probed deep to surface structures. Blind exploration or clamping is never advised. Probing and clamping can damage small nerves and other structures. Vasoconstrictors, such as epinephrine, should not be used on the digits. Consult a Hand Surgeon if wounds require deep exploration, a digital artery is injured, or hemostasis is difficult to achieve.
THE SCALP Scalp wounds frequently occur in association with other major intracranial, spinal, thoracic, and intraabdominal injuries. Control of scalp bleeding is frequently not the first priority in the multiple
FIGURE 112-5. Finger tourniquets. A. A Penrose drain wrapped about the base of the finger provides effective hemostasis. B. A finger of a surgical glove has been cut and rolled down the finger. C. A commercial finger tourniquet.
trauma patient, although continued brisk bleeding from the scalp can contribute to hemorrhagic shock.35 Techniques for vascular control of the damaged scalp should be simple, fast, and not interfere with the ongoing assessment and treatment of other injuries. A few techniques can help gain rapid control of scalp bleeding with a minimal investment of time or personnel (Figure 112-6). The fastest and most effective method is the application of Raney scalp clips (Figure 112-6A). These have been used for years by Neurosurgeons performing craniotomies.36 Scalp clips should only be used on the thick skin of the scalp. Use elsewhere can crush and devitalize thin skin or damage subcutaneous structures. If these are not available, apply hemostats at the wound edges where the bleeding is brisk (Figure 112-6B). Inject local anesthetic solution with epinephrine into the wound edges to constrict smaller vessels. A Penrose drain can be wrapped about the head as a temporary tourniquet (Figure 112-6C).12 A last method is to place a figure-ofeight suture, simple running sutures, mattress sutures, or surgical staples to temporarily close the wounds and achieve hemostasis. A more definitive closure can be performed after the patient has been stabilized. The use of Raney clips can be cumbersome. This is especially true if the Emergency Physician has little or no experience with the system. It requires a special applier, individually loading the clips on the applier, and manipulating the clips. A much simpler system is a Raney clip gun (Figure 112-7). The clips are preloaded in a magazine that snaps into the clip gun. A clip is applied by touching the tip of the gun to the scalp edge and squeezing the handle. The clip gun then ejects and applies a clip, loads the next clip, and is set to apply the next clip. The process and technique of applying a clip is similar to using a skin stapler. The clip gun is much easier, quicker, and simpler to use than the traditional method.
CHAPTER 112: Hemorrhage Control
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FIGURE 112-6. Hemorrhage from scalp wounds can easily be controlled. A. Hemostatic Raney scalp clips seal the wound edge. B. Hemostats applied about the edge of the wound. C. A Penrose drain wrapped about the head.
MAJOR EXTREMITY INJURY Amputations, major crush wounds, soft tissue avulsions, and fractures of the extremity may present with active bleeding. Diffuse bleeding from muscle and soft tissue may be difficult to localize and treat. Immobilize the extremity and apply direct pressure if discrete bleeding sites cannot be identified. Reduction of long bone fractures and immobilization of soft tissue injuries can stabilize the damaged tissue and minimize blood loss. The application of a MAST suit or air splint may stabilize bony fragments and
tamponade active bleeding.37 Consider the application of a topical hemostatic agent such as Hemcon, QuickClot, or Traumadex. These conservative and simple measures can dramatically reduce ongoing blood loss.
EXPOSED BONE Exposed bone will tend to ooze. This can be especially troublesome in amputations and crush wounds. Bone wax can tamponade these sites and temporarily halt the bleeding until more definitive action can be taken. Open a sterile package of bone wax and hold it in a sterile-gloved hand to warm it up and make it more pliable. Remove a piece of the bone wax and mold it over the end of the broken bone. Firmly push the bone wax into the bone to seal the edges. Use care to prevent lacerating your glove and finger, resulting in a potentially significant bloodborne pathogen exposure. Possible complications associated with the use of bone wax include granulomatous reactions, infection, and interference with osteogenesis. An alternative to bone wax is Ostene (Ceremed Inc., Los Angeles, CA), a water-soluble alkylene oxide copolymer that dissolves within 24 hours.
ARTERIAL INJURIES
FIGURE 112-7. The Medtronic Clip Gun Kit (Medtronic Neurosurgery, Goleta, CA). It contains the clip gun, three magazines preloaded with Raney-type clips, a clip remover tool, and an instruction manual.
Puncture wounds, open fractures, amputations, and deep lacerations may be complicated by arterial injuries. These may be obvious if they present with dramatic pulsatile bleeding. However, the elastic recoil of arteries frequently causes the damaged vessel to retract deep within the wound, only to rebleed after wound closure. Recurrent pulsatile bleeding and deep hematoma formation are characteristics of unrecognized arterial injuries. This is particularly true of puncture wounds where the damage may be deep and not visible to the examiner’s eye. These wounds may require angiography, embolization, or wound exploration to identify the source if they rebleed despite local measures.
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ASSESSMENT The ideal goal in wound care is to achieve a dry bloodless field without compromising the vitality of the tissue. Simply controlling the hemorrhage and preserving life is the goal in major trauma victims. Expediting wound closure and preventing hematoma formation is a more modest goal for minor injuries.
AFTERCARE A healthy wound is proof of adequate hemostasis. Routine wound care should verify a healthy incision line and the absence of a hematoma or an infection. Refer to Chapters 92 through 96 regarding the details of wound care and repair.
COMPLICATIONS The techniques in this chapter are all safe and effective when used as described. Complications occur when the described techniques are used in excess or in the wrong setting. The specific complications of each technique are discussed under each specific section in this chapter.
SUMMARY There are a number of techniques available for the control of hemorrhage. A methodical approach to the bleeding wound will optimize the outcome. Simple measures should be used first and progressive systematic steps taken until hemostasis is achieved. All bleeding eventually stops! The goal is to halt the bleeding before irreparable harm occurs.
113
Trigger Point Injections Danielle Campagne
INTRODUCTION Musculoskeletal pain is a significant health problem for the North American population.1–9 Such pain affects between 10% and 20% of the population and is a major cause of morbidity.1 It is estimated that approximately half of the chronic pain complaints result from a musculoskeletal origin.2 It is hypothesized that myofascial trigger point (MTrP) injections may alleviate much of this pain. It is imperative
that the Emergency Physician perform a thorough history and physical examination, with an emphasis on the neurological and orthopedic examination to exclude other causes of musculoskeletal pain.3
ANATOMY AND PATHOPHYSIOLOGY The etiology and pathogenesis of MTrPs have yet to be elucidated. Likewise, the precise mechanism by which MTrP injections inactivate the trigger point is unknown. Researchers do agree that acute trauma or repetitive microtrauma appears to lead to the development of a MTrP.6 The risk for a MTrP is increased when other factors are present, including poor physical conditioning, poor posture, and prolonged bending.7 MTrPs mostly affect the muscle groups used to maintain posture (i.e., muscles of the neck, shoulders, and back). When the head and neck region is affected, the patient may present with a tension headache or temporomandibular joint pain.6 MTrPs are hyperirritable points located within a taut band of skeletal muscle or fascia.2 When these points are compressed, they may cause referred pain, local tenderness, and autonomic changes.2 Pain may be localized or diffuse. It can be described as burning, dull, sharp, or some combination of these. Autonomic changes associated with a MTrP include dizziness, edema at the site, lacrimation, piloerection, salivation, and tinnitus. The compression of a MTrP can further lead to muscle spasm, stiffness, shortening, and fatigue.1 This may progress to impaired muscle coordination, reduced muscle strength, and decreased range of motion.1
DIAGNOSIS OF MTrPs The diagnosis of a MTrP relies on the following criteria: a tender spot with an underlying taught band, pain on palpation of the tender spot, and a local twitch response (i.e., a transient local contraction of skeletal muscle fibers in response to palpation or needling).3 While the data on clinical outcomes provide no definitive answer, the best outcomes appear to occur in patients who exhibit a local twitch response with palpation.4 The current literature provides no pathophysiologic explanation for this result. There are no laboratory, pathology, or radiology studies to identify or verify a MTrP. Identifying the palpable, taut band is critical in locating the MTrP. The MTrP can be identified by flat palpation, snapping palpation, pincer palpation, and/or deep palpation. Flat palpation uses a fingertip to slide across the skin over the affected muscle to find the MTrP (Figure 113-1). The taut band may be felt under the sliding fingertip. Snapping palpation uses the tip of the index finger to pluck the skin in an attempt to feel the underlying taut band. This motion is similar to plucking a guitar string. Pincer palpation uses the dominant thumb and index finger to firmly grasp the skin and
FIGURE 113-1. Flat palpation to identify a MTrP or taut band. A. The index finger pushes down over the MTrP or taut band. B. The index finger rolls off the tender spot and pushes the skin to one side. C. The index finger pushes the skin back to the tender spot to feel the taut band. D. The index finger rolls off the tender spot and pushes the skin to the opposite side.
CHAPTER 113: Trigger Point Injections
FIGURE 113-2. Pincer palpation to identify a MTrP or taut band. A. The skin, subcutaneous tissue, and muscle are grasped between the thumb and index finger. B. The fingers are moved back and forth (arrows) to feel the taut band as it is rolled between the fingertips.
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TABLE 113-1 Determining Isolated MTrPs Versus MTrPs Associated with Fibromyalgia Characteristic Isolated MTrPs Fibromyalgia Sexual predilection None Female Pain and tenderness Local or regional Generalized and widespread Muscle tissue Taut bands palpable Soft, no taut bands palpable Muscle range of motion Stiff and decreased Normal MTrPs Few, discrete, and Many and widespread localized Immediate response to Resolution of symptoms Poor or none injection therapy Source: Data from Simmons et al.2
CONTRAINDICATIONS muscle as a unit and roll it to identify the taut band (Figure 113-2). Deep palpation can be used to identify a deep MTrP or a superficial MTrP in an obese patient. Use the tip of the index finger to press slowly and deeply to reproduce the patient’s symptoms and identify the MTrP. Studies have utilized a variety of injectant fluids and solutions during injections of MTrPs including sterile water, sterile saline, local anesthetic solutions, corticosteroid suspensions, ketorolac, and botulinum toxin.1 No specific fluid or solution has demonstrated a clearly superior clinical outcome. Rather, it appears that the optimal injectant fluid or solution varies by Physician preference. The duration of pain relief has been found to last longer than the duration of action of the injectant. A recent meta-analysis of eight randomized and controlled clinical trials examined the type of injectant used and the resulting effect on symptom relief.1 The authors concluded that the injection of either lidocaine or botulinum toxin provided greater symptom relief than placebo (i.e., dry needling alone). No particular injectant was more efficacious than any other injectant. This finding is consistent with the general medical literature on the topic, which is still in its infancy, and provides no clear indication of effectiveness. More research is required in this area.
NONINVASIVE MTrP MANAGEMENT Numerous noninvasive techniques have been used to treat a MTrP.2,5,8 One of the more common techniques uses spray vapocoolant (e.g., ethyl chloride) in combination with passive muscle stretch to relax the taut band. Ischemic compression therapy is the application of pressure to the MTrP to produce ischemia and ablate the MTrP. Digital pressure is applied and increased until the taut band relaxes. A deep pressure or stroking massage can be used to stretch the affected muscle and relax the taut band. Physical therapy can stretch and relax the affected muscles. Transcutaneous electrical stimulation units with the electrodes placed over the MTrP can be used to stimulate and relax the underlying muscle. Ultrasound can transmit heat and vibration to a superficial MTrP with the goal of muscle relaxation.
INDICATIONS MTrP injections have been advocated for points of muscle pain that are not assisted by noninvasive therapy such as ischemic compression therapy, massage, physical therapy, spray vapocoolant, transcutaneous electrical stimulation (TENS), and ultrasound.8 There is no emergent indication for a MTrP injection in the Emergency Department.
Contraindications to MTrP injections are similar to other injection procedures. This includes the presence of a local or systemic infection, malignancy, anticoagulation therapy, a bleeding disorder, or a dermatologic condition over the injection site.5 Relative contraindications include allergies to local anesthetic agents, patients with needle phobias, and uncooperative patients. It is important to differentiate between a patient with one or more isolated MTrPs and fibromyalgia (Table 113-1). A patient with fibromyalgia can have multiple MTrPs. Do not perform MTrP injections in a patient with fibromyalgia. The injection may worsen their pain.
EQUIPMENT • • • • • • • • •
Sterile gloves Povidone iodine or chlorhexidine solution Alcohol swabs Sterile gloves Gauze 4 × 4 squares 25 or 27 gauge, 1.5 in. needle for superficial trigger points 25 or 27 gauge, 2 in. needle for deeper trigger points 3 or 5 mL syringe Injection solutions: ▶ Lidocaine without epinephrine ▶ Bupivacaine without epinephrine ▶ Sterile water ▶ Sterile normal saline ▶ Botulinum toxin A, 20 units or 0.4 mL (50 U/mL) (Botox, Allergan, Irvine, CA) diluted to 1 mL with normal saline • Ultrasound machine with a 5 to 7.5 MHz probe • Ultrasound gel
PATIENT PREPARATION Explain the risks and benefits of the procedure to the patient and/or their representative. Obtain an informed consent, either signed or verbal, with adequate documentation to support the latter method. Place the patient in a comfortable position on a gurney with the MTrP(s) exposed. Ideally, the muscle with the MTrP(s) positioned so that it is relaxed. Identify the MTrP site(s). Clean the skin of any dirt and debris. Use ultrasound to ensure there are no neurologic, tendinous, or vascular structures in the area that can be injured
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FIGURE 113-3. Identifying and securing the MTrP or taut band. A. Push with the index finger and middle finger, alternating between the fingers, to identify and isolate the MTrP or taut band. B. Compress the skin with both fingers to secure the MTrP or taut band and inject it.
by the MTrP injection. Mark the MTrP skin site with a pen. Apply povidone iodine or chlorhexidine solution over the injection site(s) and surrounding skin and allow it to dry. Follow aseptic technique for the injection procedure. Prepare multiple 3 or 5 mL syringes armed with a 25 or 27 gauge needle and containing the injection solution. The editor recommends local anesthetic solution as the injectant in the Emergency Department. The number of syringes to prepare depends upon the number of MTrP sites to be injected and the volume injected at each site.
longer palpable.7 Completely withdraw the needle. Apply pressure over the injection site to prevent bleeding and hematoma formation. Instruct the patient to slowly and fully stretch the affected muscle group.8
ASSESSMENT The patient should experience relief of their symptoms after the injection. Passively and actively stretch the affected muscle in a slow manner to stretch it out. Apply digital compression to the injection site, the MTrP, and the taut band. If symptoms are still
TECHNIQUES INJECTION TECHNIQUE Reidentify the MTrP site. Use the nondominant index and middle fingers to locate and isolate the MTrP or taught band (Figures 113-3A & B). Insert the needle into the skin approximately 1 cm away from the MTrP or taught band, at a 30° angle to the skin, and aimed at the MTrP or taut band. Advance the needle into the MTrP or taut band. Insert the needle briskly, but also in a controlled manner. Use a “fast in, fast out” approach to elicit a local twitch response when the tip of the needle hits the MTrP or taut band.8 Aspirate to ensure that the tip of the needle is not within a blood vessel. Inject the solution within the syringe. Common practice is to inject between 0.5 and 2.0 mL total per MTrP.5 This volume can be injected into the one location of maximal tenderness or numerous sites in a fanlike pattern within the MTrP (Figure 113-4).9 Once the injection is completed, withdraw the needle to the skin surface but do not completely remove it from the skin. Allow the injection solution to work for up to a minute. Reinsert the needle into the MTrP in a fanlike pattern until the local twitch response is no longer elicited or resisting muscle tautness is no longer palpable.7 Completely withdraw the needle. Apply pressure over the injection site to prevent bleeding and hematoma formation. Instruct the patient to slowly and fully stretch the affected muscle group.8
DRY NEEDLING The technique of dry needling involves inserting a needle into multiple sites within the MTrP or taut band without injecting any fluid or solution. This is similar to acupuncture. Insert the needle as described above. Withdraw the needle until the tip is just below the skin surface. Redirect and reinsert the needle in a fanlike pattern into a different location within the MTrP or taut band. Continue this process several times until the local twitch response is no longer elicited or resisting muscle tautness is no
FIGURE 113-4. Injection of the MTrP or taut band. The needle is inserted through a single skin puncture and into multiple places within the MTrP or taut band in a fanlike pattern.
CHAPTER 114: Escharotomy
present, repeat the procedure with local anesthetic solution or by dry needling. Observe the injection site and apply pressure to control any bleeding.
AFTERCARE Apply a simple adhesive bandage over the injection site. Postinjection soreness is expected and can be managed with acetaminophen or nonsteroidal anti-inflammatory drugs. Encourage the patient to use the affected muscle through its full range of motion, but avoid strenuous activity for 1 to 3 days after the injection. Instruct the patient to return to the Emergency Department immediately if they develop fever, chills, swelling at the injection site, redness at the injection site, or any drainage from the injection site.
COMPLICATIONS The complications are the same as any injection procedure, including infections and needle breakage. An allergic reaction to the injection fluid or solution is possible. Treat this as any other allergic reaction. A thorough history may prevent an allergic reaction to the injectate. Never aim the needle at an intercostal space to prevent an iatrogenic pneumothorax.7 Hematoma formation following injection can be minimized with proper technique and the application of pressure over the soft tissue after the needle is withdrawn.2 Never inject the patient when they are standing or sitting in a chair. Ensure that the patient is always on a gurney and the side rails are upright to prevent injury if the patient becomes vasovagal or experiences syncope. Injury and inadvertent injection to adjacent structures can be avoided by knowing the local anatomy and using ultrasonography before the injection to identify adjacent structures.
SUMMARY MTrP injections can be performed in the Emergency Department. They are simple, quick, and effective to manage a patient’s pain. The efficacy of MTrP injections has not yet been established. However, MTrP injections may serve as part of a treatment plan to offer quick relief of myofascial pain when other noninvasive therapies have been unsuccessful.
114
Escharotomy Michael A. Schindlbeck
INTRODUCTION Few injuries have the same capacity for physical destruction and emotional devastation as do thermal burns. They are relatively common presentations that often require resource-intensive management. The preceding decade saw nearly 500,000 burn injuries per year receiving medical care in the United States. Over 40,000 of these patients required inpatient treatment for their injuries, and up to 25% of these injuries were work related. The associated expenses are staggering. The mean hospital stay was in excess of 1 week and at an average cost over 50,000 dollars per admission. Over this same 10-year period, an average of over 4000 individuals per year died as a result of burn-related injuries. Fires and burns now represent the fifth leading cause of unintentional
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injury deaths in the United States.1 Conversely, less than 6% of the above patients who were admitted to a recognized burn center subsequently died as a result of their injuries.2–4 These data underscore the need for rapid and effective emergency care focused on facilitating the successful transfer of these patients to specialized burn centers. The initial management of these patients invariably falls upon the Emergency Department. The Emergency Physician needs to be well versed in the recognition of acute thermal injuries, their associated complications, and their appropriate treatment. Thermal injuries have the potential to affect any body surface, both internally and externally, that a heated medium comes into contact. The overall depth and degree of injury is multifactorial. It is also typically proportional to the temperature of the source medium, its unique specific heat, the actual rate of energy transfer, and the overall duration of tissue exposure. This chapter focuses on the skin and its response to burn injuries.
ANATOMY AND PATHOPHYSIOLOGY Skin exposure to any significant heat source results in a spectrum of pathophysiological responses. An initial coagulation necrosis occurs as thermal energy is transmitted directly into living tissue. These cells subsequently die and lyse, spilling their intracellular contents and increasing the surrounding interstitial oncotic pressure. These processes serve to trigger a secondary edematous reaction in the surrounding tissues. Cellular breakdown releases a host of generalized inflammatory markers including histamines, prostaglandins, cytokines, and interleukins. These agents further exacerbate the localized edematous reaction via vasodilation and increased capillary permeability.5 Burns involving over 20% of a patient’s total body surface area (TBSA) can result in secondary injury extending beyond the locally involved tissues. The previously described inflammatory outburst can become significantly large enough to produce a systemic pathophysiologic response of internal fluid shifts and external fluid losses. Inadequate fluid resuscitation can result in tissue hypoperfusion and multisystem organ dysfunction. Moreover, a secondary systemic inflammatory response syndrome (SIRS) can further complicate the clinical course of patients whose burns involve greater than 30% TBSA. This frequently results in widespread intravascular hemolysis, acute renal failure, and acute lung injury.6,7 A global hypermetabolic state tends to accompany these injures. When greater than 30% to 40% of a patient’s TBSA is involved, secondary catecholamine release can raise the resting metabolic rate approximately two to three times above baseline. The consequent catabolic tissue breakdown further exacerbates the emerging multisystem organ dysfunction.5,8 These burns are associated with significant morbidity and mortality. Survivability rates are indirectly proportional to the TBSA involved. Of special note is the loss of a protective functioning epidermis as severe and overwhelming infection becomes a significant potential complication in those who survive beyond the initial resuscitative period.9 Systemic organ failure from the “burn sepsis” continues to be a leading cause of death in these individuals. Burns are classified based upon the overall depth of injury sustained. First-degree burns are limited solely to the epidermal layer. They typically present as a tender erythematous region of skin. This redness arises as the underlying dermal capillaries dilate in response to the overlying injury. Deeper tissues are not directly involved and the capillary walls remain intact. This explains the blanchable nature of these burns on physical examination. Blistering of the skin, indicating involvement of the underlying dermis, is not seen with first-degree burns. Classic examples include flash burns and sunburns. Despite extensive surface area involvement, these burns
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do not generally illicit the systemic pathophysiologic response described above. Do not include first-degree burns when calculating the overall TBSA affected. Second-degree burns are the partial thickness injuries. These burns extend into but not through the dermis. They are subdivided into superficial second-degree and deep second-degree burns. Superficial second-degree burns are typically moist to the touch, pink to reddish in color, blanchable with gentle pressure, and covered with tensely distended blisters. Cutaneous nerves, located in the uninvolved underlying deeper dermal layer, remain viable bestowing an exquisitely painful character to these burns. Conversely, deep second-degree burns involve the deeper reticular dermis and differ noticeably in appearance. They tend to be drier in texture and have a more blanched whitish complexion. These injuries tend to be less painful than their superficial counterparts due to destruction of the cutaneous nerves. Full thickness burns involve the destruction of the entire epidermal and dermal tissues and are classified as third-degree burns. Coagulation necrosis imparts a dry leathery appearance to these burns. The overlying tissue is insensate secondary to the obliteration of the cutaneous nerves. The dermal proteins in third-degree burns are heated and tend to contract, facilitating the formation of a constrictive eschar of scar tissue. Rare scenarios where the tissue destruction extends through the dermis and into the underlying tissues (e.g., muscle, bone, and fascia) are categorized as fourth-degree burns. These injuries are catastrophic in appearance and tend to result in extensive tissue loss.10 Burn injuries can generate an extensive redistribution of fluids into the interstitial spaces. Aggressive fluid resuscitation will help to limit the consequent invariable hypoperfusion but does nothing to limit further leakage of fluids into the interstitium. This third spacing can lead to significant elevations in the localized hydrostatic pressures in tissues already constricted by an extensive overlying eschar. Impairment in regional lymphatic and venous drainage further exacerbates this adulteration of the local pressure gradient. Eventually, the normal arteriolar perfusion pressure will be overwhelmed and result in distal tissue hypoperfusion. Distal tissue necrosis can progress to limb loss if the burn occurs on an extremity. Swelling and scarring can result in the loss of a functional airway if the burn occurs over the neck. Burns occurring across the torso can produce an abdominal compartment syndrome, progressing to intra-abdominal organ ischemia, impaired diaphragmatic excursion, and reduced cardiac output secondary to diminished venous return.11–13 Significant thoracic burns can also impede the dynamic chest wall motions of respiration producing a further restrictive ventilation that can progress to respiratory failure.14
Any signs and symptoms of limb hypoperfusion should be taken seriously. A restrictive etiology should be considered only if hypoperfusion persists despite adequate volume resuscitation as hypovolemia is the most likely etiology of impaired tissue perfusion immediately after the burn injury. Perform and document frequent and repeat physical examinations including an assessment of overall skin appearance, distal capillary refill, peripheral pulse checks, any motor deficits, and any sensory deficits. Depending upon the presence of palpable pulses as the sole means to approximate compartmental pressures will grossly underestimate the need for decompression.15 Several methods are available to aid the Emergency Physician in frequently assessing for tissue hypoperfusion. Bedside arterial Doppler provides an easy means to gauge peripheral perfusion. It is concerning if any signs of a progressive reduction in arterial flow occurs. The absence of arterial flow on a bedside Doppler is an indication for emergent escharotomy. Keep in mind that the presence of Doppler pulses does not necessarily indicate adequate perfusion. Pulse oximetry provides another useful adjunct. A distal oxygen saturation of less than 95% in a circumferentially burned extremity has been shown to be an indicator for an emergent escharotomy.16 Compartmental pressures can usually be measured quickly at the bedside. An intracompartmental pressure of ≥40 mmHg is an indication for an escharotomy. Consider an escharotomy for intracompartmental pressures between 25 and 40 mmHg. Refer to Chapter 74 regarding the complete details of compartment pressure measurement. Significant burns to both the chest and abdomen can result in restricting ventilation. Respiratory distress is generally multifactorial in burn patients. A concurrent inhalation injury or secondary ARDS should be entertained in the differential diagnosis. Early intubation and mechanical ventilation is essential in any burn patient exhibiting respiratory distress. Mechanically ventilated patients with severe truncal burns, persistent arterial hypercapnia, and elevated peak inspiratory pressures (although often confounded by concurrent airway edema and secondary bronchospasm) are objective signs suggesting a significant restrictive respiratory physiology. An emergent escharotomy in these patients could be a lifesaving procedure. Facial burns can result in eschar formation around the eyes and mouth. Measure intraocular pressure if an eschar surrounds the eye. Elevated intraocular pressure should be decompressed with a lateral canthotomy. Refer to Chapters 156 and 162 regarding the complete details of intraocular pressure measurement and a lateral canthotomy, respectively.
INDICATIONS
No specific contraindications exist for performing an escharotomy provided the above indications are satisfied. Concern for possible medical futility should arise in those patients with no chance of salvageability, although this is very difficult to determine within the Emergency Department.
The general indication to perform an escharotomy is to limit the circulatory or respiratory insult caused by an overlying circumferential burn. These indications can also be present with a significant noncircumferential burn. The development of a significant restrictive physiology often requires several hours after the initial burn. Most patients could be successfully transported to a specialized burn center within this time span. Invasive means to assess compartmental pressures (Chapter 74) should not be undertaken at the expense of proper fluid resuscitation and preparation for transport. The Emergency Physician must maintain a high index of suspicion to limit any further injury to viable tissues. Once the decision to perform an escharotomy is made, it should be performed without delay. If possible and time permits, perform the escharotomy in consultation with the accepting burn center and/or Burn Surgeon.
CONTRAINDICATIONS
EQUIPMENT • • • • • • •
Glove, gown, and face mask Povidone iodine or chlorhexidine solution #10 scalpel blade on a handle Electrocautery unit, optional Gauze 4 × 4 squares Local anesthetic solution Needles and syringes
CHAPTER 114: Escharotomy
PATIENT PREPARATION This procedure is considered life and/or limb sparing. Inform the patient for the need to perform an escharotomy, its risks and benefits, and the outcome if not performed. Document the discussion in the medical record. The patient’s medical condition often precludes them from signing a consent form. Despite the fact that escharotomies are performed upon tissues previously destroyed by full thickness burns, some intermittent nerve function can persist. This may necessitate the use of local anesthesia and/or procedural sedation. If not contraindicated, administer some form of procedural sedation (Chapter 129) in the conscious patient for pain control as well as to limit the profound anxiety elicited by this procedure. Strict aseptic technique should be followed. Clean the skin of any dirt or debris. Apply dilute povidone iodine or chlorhexidine solution to the skin and allow it to dry. This procedure has the potential to introduce a devastating infection.
TECHNIQUES Make the skin incisions along the proper plane with a #10 scalpel blade or an electrocautery unit. Electrocautery has the added ability to coagulate the potential bleeding encountered from inadvertently incised superficial subcutaneous vessels. Limit the depth of the incision to the dermis. Use extreme caution to avoid overaggressively extending these incisions too deeply and injuring the underlying deep investing fascia, muscles, and/or tendons. There is a pressure buildup underlying the constricting tissue. A properly placed incision should elicit a rapid separation of the eschar exposing the underlying subcutaneous fat. Carefully run a gloved fingertip along the incision lines to detect any residual connecting bands of tissue requiring further incision. To ensure an adequate release, continue the incision across the entire eschar and extending 1 to 2 cm into the unscarred tissue on either end. Cosmetic concerns are not a concern as the incised tissue will often require eventual skin grafting, provided the patient survives.
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FACE ESCHAROTOMY The face is commonly involved in burn injuries. Eschars can form on the face just as they can form on other areas of the body. A patient complaint of any visual disturbance or burns around the eye requires a thorough investigation. This includes measuring visual acuity, a topical fluorescein examination, a fundoscopic examination, and measurement of intraocular pressure. Refer to Chapters 153 and 156 regarding the complete details of these examinations. Elevated intraocular pressure may require a decompressive lateral canthotomy and cantholysis. Refer to Chapter 162 regarding the complete details of this procedure. Perioral burns can form eschars. These eschars may limit or prevent mouth opening. An escharotomy may be required to aid in oropharyngeal suctioning and orotracheal intubation. Make the escharotomy incisions at the bilateral corners of the mouth and extending directly posterior (in the supine patient) and approximately 4 to 5 cm long (Figure 114-1A). Make the incisions very superficial to prevent injury to the underlying facial artery, cranial nerves, superficial facial structures, and the parotid gland.
NECK ESCHAROTOMY Significant burns to the neck can result in the formation of a constrictive eschar that can compromise the airway. Make paired vertical incisions on the posterolateral surfaces of the neck from the mastoid process to the clavicle (Figure 114-1A). Meticulous care and attention should be given to always remain posterior to the clavicular border of the sternocleidomastoid muscle. This will avoid injury to the internal jugular vein, carotid artery, thyroid gland, trachea, and vagus nerve.
TORSO ESCHAROTOMY Perform a thoracic escharotomy by extending bilateral vertical incisions from the lateral clavicle to the costal margins along
FIGURE 114-1. The location of incisions for escharotomies. A. The head and neck. B. The extremities and torso. C. The hand and fingers.
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the anterior axillary lines (Figure 114-1B). Use caution in female patients to avoid incising directly through the breast tissue. Instruct an assistant to grasp the breast and move it medially to avoid the escharotomy incision line. In those patients whose burns also involve a significant portion of the abdominal wall, extend the thoracic incision inferiorly beyond the costal margins and across the entire eschar to ensure adequate decompression (Figure 114-1B). Make a horizontal bridging incision along the inferior costal margin in those patients whose burns extend from the thorax and onto the abdomen to support proper respiratory mechanics (Figure 114-1B). Circumferential burns of the penis require an escharotomy to decompress the area and prevent ischemia. Distal ischemia can rapidly progress and produce significant tissue loss. Make bilateral incisions along the lateral margins of the body of the penis. Meticulous care and attention should be given to avoid injuring the dorsally located neurovascular structures that lie between the 10 o’clock and the 2 o’clock position.
UPPER EXTREMITY ESCHAROTOMY Perform an upper extremity escharotomy on the medial and lateral aspects of the involved limb, extended along the line dividing the flexor and extensor surfaces (Figure 114-1B). Place the upper extremity supine to ensure adequate landmark identification. The areas surrounding joints are sites of severe potential restriction due to relatively tight tissue adherence. Use caution when extending the incisions across these locations. Meticulous care and attention should be given to avoid the ulnar nerve along the medial surface of the elbow as it courses posterior to the median epicondyle and the superficial branch of the radial nerve along the lateral surface of the wrist as it courses superficially above the radius. If the hand is involved, extend the forearm incisions to include the thenar and hypothenar eminences (Figure 114-1C). Further hand decompression can be accomplished by making vertical incisions down the four intermetacarpal grooves on the dorsum of the hand (Figure 114-1C). The fingers can be decompressed with linear incisions along the middle of the radial and ulnar surfaces, between the flexor and extensor surfaces (Figure 114-1C). In an attempt to limit the potential damage to a patient’s grasping surfaces, incise the ulnar finger surfaces (radial surface on the thumb) and assess if this unilateral incision is sufficiently adequate to restore perfusion prior to automatically incising the corresponding opposing surface.17
LOWER EXTREMITY ESCHAROTOMY The lower extremity should be approached in a similar manner, with incisions extending along the groove between the flexor and extensor surfaces (Figure 114-1B). Meticulous care and attention should be given to avoid damaging the common peroneal nerve along the lateral knee as it courses superficial to the fibular head and the posterior tibial artery along the medial ankle as it courses posterior to the medial malleolus. If the foot is involved, extend the incisions along the medial and lateral borders of the foot to the great toe and the fifth toe, respectively (Figure 114-1B). Decompress the toes in a manner similar to the fingers.
TECHNIQUE FOR PEDIATRIC PATIENTS Pediatric patients have a higher surface area to volume ratio than does an adult. Consequently, burns pose a greater risk for significant external fluid losses and the rate of fluid resuscitation needs to be adjusted accordingly. More aggressive fluid resuscitation, however, increases the likelihood for pathologically significant elevations in
the perfusion pressures of affected tissues. Infants and younger children depend to a greater extent upon diaphragmatic excursion and abdominal wall mobility for normal respiratory function. They are therefore more susceptible to significant respiratory compromise from extensive truncal burns. This necessitates that the treating Emergency Physician possesses both a high index of suspicion and the technical ability to intervene surgically. The patient preparation and escharotomy techniques are the same as in an adult.
ASSESSMENT The response to an escharotomy should be almost immediate with the signs of improving distal perfusion of the extremities or improved ventilation. The distal extremity should demonstrate decreased pallor and return of a natural skin color, return of sensation, appropriate Doppler arterial flow, and appropriate pulse oximetry. Provided adequate respiratory mechanics, distal pulse oximetry readings should rapidly climb into a normal range.18 Lack of improvement in distal perfusion should alert the Emergency Physician to either an inadequate surgical decompression or an insufficient fluid resuscitation. If there is no improvement in perfusion despite appropriately addressing these two concerns, consider an underlying intrafascial compartment syndrome that would require an emergent fasciotomy. Please refer to Chapter 74 regarding compartment pressure measurements and Chapter 75 for the details of performing a fasciotomy.
AFTERCARE Continue routine burn care and fluid resuscitation as necessary. Manage any continued bleeding from the escharotomy incisions with the application of pressure or electrocautery. Cover the escharotomy incisions with sterile saline-soaked gauze and an outer dressing. Frequently reassess the patient to rule out the development of additional tissue ischemia or respiratory compromise that would indicate the need for further extension of the initial escharotomy incisions. Transfer the patient to a specialized burn center or an intensive care unit to continuously monitor and manage the patient.
COMPLICATIONS As with any invasive procedure, bleeding can be a significant complication. This is rare when the escharotomy incisions are properly limited to the dermis. Bleeding can be extensive when an underlying subcutaneous vessel is incised. This is often complicated by the consumptive coagulopathy that frequently accompanies these burns. Electrocautery is an attractive option to limit such bleeding if encountered. Otherwise, direct pressure should generally suffice. Some blood vessels may require ligature for definitive hemostasis. The burn-damaged epidermis can no longer function to protect deeper tissues from the external environment. Furthermore, the overlying eschar of necrotic tissue provides an ideal environment for uncontrolled bacterial colonization. Escharotomy incisions provide a direct route for bacterial penetration into susceptible subcutaneous tissues if sterile precautions are not properly maintained. This can result in catastrophic infection and burn sepsis. Inadvertent injury of deeper structures such as blood vessels, nerves, and tendons can occur. This is preventable by controlling the depth of the incisions and not extending into and through the subcutaneous tissues. This is especially true when incising over high-risk areas as previously described. Making an escharotomy incision on the fingers is controversial. There is little to no muscle at risk of ischemia in the fingers. The fingers primarily consist of bone, ligaments, subcutaneous fat, and
CHAPTER 114: Escharotomy
tendons. These structures are quite resistant to ischemia. A finger escharotomy can expose the metacarpophalangeal and interphalangeal joints, make them prone to infection, and require a subsequent fusion or amputation. A final complication is the inadequate release of the overlying restrictive eschar. Ongoing tissue ischemia can lead to permanent disability from disfiguring muscle contractures, irreparable neurologic damage, or limb loss. Rhabdomyolysis can lead to lifethreatening electrolyte abnormalities and acute renal failure. Several authors advocate extending the escharotomy incisions 1 to 2 cm beyond the eschar border into viable tissue. A secondary reperfusion injury can follow the primary decompression as blood once again streams into previously hypoperfused tissue. The consequent swelling can cause the formation of a secondary underlying intrafascial compartment syndrome.
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SUMMARY Thermal burns are frequently encountered injuries prompting patients to seek medical care. Their associated morbidity, mortality, and costs of treatment can be astronomical. Emergency Physicians often provide an essential role in the acute resuscitation and stabilization of these patients prior to their ideal transfer to a specialized burn center. Severe burns can destroy the natural elastic properties of skin and result in the formation of constrictive overlying eschars. If not recognized and treated, these eschars can result in catastrophic limb loss, airway compromise, or respiratory failure. When performed properly, an escharotomy can be a limb and life-saving procedure that, at the least, grants the patient a significant chance to undergo more specialized and definitive burn care.
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Neurologic and Neurosurgical Procedures
115
Lumbar Puncture Eric F. Reichman, Kevin Polglaze, and Brian Euerle
INTRODUCTION Meningitis and subarachnoid hemorrhage (SAH) are serious life-threatening conditions. They require prompt and accurate diagnosis in the Emergency Department due to their significant morbidity and mortality. There are many diagnostic modalities available to the Emergency Physician to assist in the diagnosis. However, the lumbar puncture (LP) is still considered the gold standard. The LP is a procedure that is often performed in the Emergency Department to obtain information about the cerebrospinal fluid (CSF) to aid in the diagnosis of a variety of medical conditions. Knowledge about the proper indications, contraindications, various techniques, equipment, and recognition and treatment of its complications is vital to any Emergency Physician who performs this procedure. An LP should be performed after a thorough neurological exam. Significant morbidity and mortality can result if the procedure is performed on the wrong patient.
8
ANATOMY AND PATHOPHYSIOLOGY While the entire cavity of the brain and spinal cord has a volume of approximately 1650 mL, CSF occupies approximately 150 mL of this volume. The brain literally floats in the CSF because the specific gravity of the CSF and brain are approximately the same. Approximately 500 mL (0.35 mL/min) of CSF is produced each day. Most (over two-thirds) of the CSF is produced by the choroid plexus within the lateral ventricles. Small amounts of choroid plexus can also be found in the third and fourth ventricles. Small amounts of CSF are secreted by the ependymal surfaces of the ventricles. A minimal volume of CSF is produced by the brain through the small perivascular spaces that surround the blood vessels entering the brain substance. The flow of CSF through the ventricular system is rather simple (Figure 115-1). CSF produced in the lateral ventricles flows through the foramina of Monro into the midline third ventricle. It then passes through the Aqueduct of Sylvius into the fourth ventricle. From the fourth ventricle, the CSF flows into the cisterna magna via two lateral openings (foramina of Luschka) and one midline opening (foramen of Magendie). The cisterna magna is located beneath the medulla and cerebellum and is continuous with the subarachnoid space that surrounds the brain and spinal cord. The CSF then flows through the subarachnoid space to
Arachnoid villi
Dura Sagittal sinus
Arachnoid
Lateral ventricle
Choroid plexus
Tentorium cerebelli Foramen of Monro Third ventricle
Aqueduct of Sylvius Foramen of Luschka Fourth ventricle
Foramen of Magendie
FIGURE 115-1. CSF circulation around the brain and upper spinal cord. 747
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bathe the brain and spinal cord. The CSF is absorbed back into the venous system by way of arachnoid villi. CSF pressure should average 130 mmH2O when measured in the lateral decubitus position. It can range from 70 to 180 mmH2O in a normal person. Since the CSF production rate is constant, the pressure is regulated by the rate of CSF absorption by the arachnoid villi that act as one-way valves into the venous blood of the dural sinuses. Certain disease states may impede reabsorption and lead to increased intracranial pressure (ICP).1 Familiarity with the anatomy of the spinal column is important when performing an LP. The anatomy will be briefly reviewed from superficial to deep as the spinal needle traverses the midline structures. The skin and subcutaneous tissue are the first layers encountered. These are followed by the supraspinous and intraspinous ligaments, located between the spinous processes of adjacent vertebrae. Deep to these ligaments is the thick ligamentum flavum that accounts for the characteristic “pop” that is described when performing an LP. The next layers encountered are the epidural fat, in the epidural space, followed by the dura mater, and finally the subarachnoid space. When considering the lateral approach, there are subtle anatomic differences. The layers include skin and subcutaneous tissue followed by the paraspinal ligaments. The intraspinous ligament is less likely to be encountered with an extreme lateral approach, as this is a midline structure. The ligamentum flavum and deeper structures should be encountered in the same fashion regardless of the approach.
FIGURE 115-2. Physical examination of meningeal signs. A. Brudzinski’s sign. Upon passive elevation of the head by the examiner, the patient complains of neck and low back pain, and may have involuntary flexion of the knees and hips suggesting meningeal irritation. B. Kernig’s sign. Begin with the patient starting in a supine position with their hips and knees flexed 90°. Gradually extending the knee causes the patient to complain of neck or lower back pain.
INDICATIONS There are many indications for performing an LP. The primary indications to perform an LP are the suspicion for a central nervous system infection, such as meningitis, or for a SAH. It may also be performed for the evaluation of new-onset seizures, to obtain CSF biomarkers, to relieve CSF pressure, and confirm the diagnosis of pseudotumor cerebri. Other indications include CSF evaluation for central nervous system diseases (e.g., Guillain–Barré, multiple sclerosis, and systemic lupus erythematosus), to confirm demyelinating or inflammatory diseases, to administer antibiotics or chemotherapeutic agents, to aid in radiologic imaging procedures (e.g., cysternography or myelography), and to diagnose meningeal carcinomatosis.
SUSPICION OF MENINGITIS IN ADULTS An LP should be performed in adults when there is a clinical suspicion of a central nervous system (CNS) infection. While a fever is often present (most sources consider a fever >100.4°F or >38°C), it is not a dependable sign. Meningeal signs include nuchal rigidity, Kernig’s sign, and Brudzinski’s sign. Other signs of a possible CNS infection include a severe headache, photophobia, or a petechial rash. Unfortunately, these signs may or may not be present. This is especially true in the elderly, the young, or the immunocompromised patient. An LP should be a routine procedure in febrile adults with an altered mental status and no source of fever. The most commonly looked-for signs of meningitis include the Kernig’s sign and the Brudzinski’s sign (Figure 115-2). Place the patient supine to test for these physical examination signs. Passively flex the patient’s head until their chin touches the sternum. Flexion of the patient’s hips and knees in response to the head flexion is known as the Brudzinski’s sign (Figure 115-2A). The patient may also experience neck pain and resistance to flexion if meningitis is present. Passively flex one of the patient’s legs to 90° at the hip and to 90° at the knee (Figure 115-2B). Passively extend the knee. Pain in the lower back or resistance to knee extension is known as the Kernig’s sign.2
SUSPICION OF MENINGITIS IN CHILDREN When evaluating the febrile infant, the decision of whether to perform an LP will be based on the clinical suspicion of meningitis, the age and appearance of the child, and whether an identifiable source of fever is present. The Emergency Physician will often be faced with a well-appearing febrile infant with no obvious source of fever. Until recently, many institutions managed all febrile infants less than 3 months old with a full sepsis workup (including LP) and admission to the hospital. Guidelines based on an extensive literature review and a metaanalysis by an expert panel identify patients at low risk for serious bacterial infection (SBI), where LP and hospitalization may or may not be indicated.3 Examples of serious bacterial infections include meningitis, sepsis, osteomyelitis, septic arthritis, urinary tract infections, pneumonia, and enteritis. Since clinical evaluation alone is inadequate to exclude serious bacterial infections in infants, it must be combined with laboratory studies that can define low-risk criteria. These criteria apply to nontoxic-appearing infants with reliable parents and prearranged follow-up. A more detailed discussion regarding the evaluation of the child with a fever is beyond the scope of this chapter. It should be noted that any febrile child, regardless of age, who appears “toxic” should have an LP as an integral part of the sepsis workup. Certain bacterial infections have a high propensity for dissemination and systemic bacteremia. Examples include epiglottitis, buccal cellulitis, periorbital cellulitis, and septic arthritis. These children should also be considered for a LP in their evaluation and work-up.
IS AN LP INDICATED FOR THE FIRST FEBRILE SEIZURE? The Emergency Physician will be faced with the decision of whether to perform an LP when evaluating infants and children with a first
CHAPTER 115: Lumbar Puncture
febrile seizure. The American Academy of Pediatrics recommends that a LP be “strongly considered in infants less than 12 months of age” and “considered in children 12 to 18 months of age.”4 This is based on the lack of clinical signs and symptoms often associated with meningitis in this age group. For children over 18 months of age, an LP should only be performed if there is a clinical suggestion of meningitis. Clinical signs and symptoms that have been shown to correlate with the presence of meningitis include petechiae, nuchal rigidity, coma, persistent drowsiness, Kernig’s or Brudzinski’s sign, status epilepticus, and paralysis.5 Benign febrile seizures are those that occur in children 3 months to 5 years of age, are associated with a fever at the onset of an illness, have a single generalized seizure lasting less than 15 minutes in a child with normal psychomotor development, have no history of prior febrile seizures with this current illness, and have no evidence of an intracranial infection or acute neurological illness. These children generally appear well except for the fever and generally do not require a LP. This is based upon the level of Emergency Physician comfort in a nontoxic-appearing child. Complex febrile seizures are those that do not meet the criteria of a benign febrile seizure. These children require a complete septic work-up including an LP. Criteria include seizures that begin focally, seizures lasting over 15 minutes, children with a prolonged postictal period, suspicious findings on physical examination, children less than 12 months of age, children already receiving antibiotics, children who have seen a Physician for an illness in the preceding 24 hours, or those who have had multiple seizures during a single period of illness. Seizures not associated with the onset of an illness have an increased risk of being due to meningitis or bacteremia. Children seizing upon presentation to the Emergency Department are considered to be seizing over 15 minutes or to have recurrent seizures. Suspicious findings on physical examination that suggest a complex seizure include rashes, petechiae, cyanosis, hypotension, abnormal respirations, increased or floppy tone, stiff neck, difficult to console, deviated eyes, doll’s eyes, nystagmus, ataxia, photophobia, bulging or tense fontanelles, unable to fix and follow, or children that do not respond to voice or painful stimuli.
SUBARACHNOID HEMORRHAGE A suspected SAH is the other common indication for an LP. The classic description of a SAH is the sudden onset of an excruciating headache (“thunderclap”) during exertion that may or may not be associated with syncope, nausea, vomiting, diaphoresis, or meningeal signs. Physical examination findings may include nuchal rigidity, an altered level of consciousness, papilledema, retinal hemorrhage, third-nerve palsy, sixth-nerve palsy, bilateral lower leg weakness, nystagmus, ataxia, aphasia, or hemiparesis. Additional risk factors for a SAH include cigarette smoking, hypertension, alcohol abuse, a family history of SAH, polycystic kidney disease, connective tissue disorders, or sickle cell anemia. It is estimated that 20% to 50% of patients with a SAH may have sentinel bleeds or small leaks that precede the major bleeding event. It is important to diagnose a sentinel bleed because early management and intervention can improve the overall outcome for the patient. A sentinel bleed may precede a major SAH by hours, days, weeks, or months.6,7 A CT scan of the head is often the first study used to investigate a patient complaining of the sudden-onset headache. The sensitivity of CT scan for SAH can range from 92% to 98% when performed within 24 hours of the onset of symptoms.8–10 The sensitivity decreases markedly (about 76%) when performed 48 to 72 hours after onset of symptoms.11–12 The head CT scan can be negative in the patient with a sentinel bleed.
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An LP must be performed if the CT scan is negative and a SAH is still suspected.10 The presence of xanthochromia or red blood cells in the CSF will confirm the presence of bleeding. While the CSF will usually confirm a SAH, it is possible that the LP may be negative despite a recent SAH if there has not been sufficient time for the red blood cells to migrate to the lumbar spine area. In this case, despite a negative head CT scan or a negative LP, a cerebral angiogram or follow-up LP in 12 to 18 hours should be performed.
CONTRAINDICATIONS Knowledge of the contraindications to performing an LP is important. The Emergency Physician will often have to weigh the potential risks of performing the procedure with the benefits of obtaining the CSF. The decision must be made whether the procedure should be performed immediately or can be delayed until further studies are completed. Absolute contraindications to performing an LP include a cellulitis or abscess at the skin puncture site or signs and symptoms of increased ICP except for idiopathic intracranial hypertension (IIH, previously known as pseudotumor cerebri). The LP should be delayed in patients with an unstable airway, hypotension, shock, or status epilepticus until the patient has been stabilized. Hypoxemia, clinical deterioration, apnea, and cardiopulmonary arrest are reported complications of LP in unstable patients. Relative contraindications to performing an LP include the presence of a brain abscess, epidural or subdural fluid collection, brain tumors, and spinal cord tumors. Note that antibiotics should not be delayed if meningitis is suspected and the LP must be delayed. If meningitis is highly suspected but the patient is unstable, treatment should be initiated with parenteral antibiotics and the LP delayed until the patient’s condition is stabilized.
INCREASED ICP An LP is relatively contraindicated in the presence of increased ICP.13–15 This includes patients with space-occupying lesions (e.g., tumor or abscess), lateralizing signs such as hemiparesis on the physical examination, or when signs of uncal herniation are present (unilateral third-nerve palsy). Brain herniation or coning has also been reported in patients with meningitis and increased ICP. The sudden drop in ICP induced by an LP may precipitate a pressure cone or herniation. Pseudotumor cerebri, now known as IIH, has been treated with a combination of medicines and repeated LPs to decrease ICP. Removal of CSF for IIH is a common diagnostic and therapeutic procedure in the Emergency Department. The use of LP in IIH is sometimes questioned. Many of these patients are obese, making an LP more difficult to perform, often requiring multiple attempts, and painful for the patient. The CSF removed reforms within a few hours, thus the LP provides only temporary relief of the patient’s symptoms. Consult a Neurologist before performing an LP in the patient with IIH. An LP may be required to make the initial diagnosis of IIH, but may be unnecessary in the patient when the diagnosis has been made previously.
BRAIN ABSCESS Patients with brain abscesses are at high risk for herniation.16,17 Brain abscesses may present with a progressively worsening headache, low-grade fever, and the development of focal neurological signs (e.g., hemiparesis, papilledema, visual field deficits, and mild obtundation). Suspect a brain abscess in patients with a history of otic or paranasal sinus infection, orbital cellulitis, chronic pulmonary or
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abdominal infection, endocarditis, congenital heart disease, recent dental procedures, dental abscesses, recent neurosurgery, craniofacial trauma, open skull fractures, or recent meningitis.
WHEN IS A CT SCAN INDICATED BEFORE AN LP? It should be emphasized that increased ICP by itself is not necessarily a contraindication to an LP. ICP is usually mildly elevated in patients with IIH or meningitis.18–20 A CT scan does not need to be routinely performed in straightforward cases of suspected meningitis in the patient with a normal neurological examination.21–25 The inability to visualize the optic discs does not constitute a focal finding and, by itself, is not an indication for a head CT scan prior to an LP.23 Despite this, there are occasional cases of herniation in patients with a normal CT scan.13,14,19 Most literature suggests that CT scans be performed prior to LP when patients are comatose or altered, have focal neurological signs, are HIV positive, have a progressively worsening headache, or have papilledema.23–25 The lack of papilledema is not always a reliable sign of normal ICP, as it often takes greater than 48 hours to develop papilledema.21 Papilledema may be absent in up to 15% of adults and up to 50% of children with early increased ICP. The CT scan should be evaluated for mass lesions, shift of midline structures, or hydrocephalus due to obstructing masses, cisternal obstruction, and cerebral edema.25 There are three findings that may predispose a patient to herniation if an LP is performed.26 The first finding is midline shift. This suggests unequal pressures across the midline. The second finding is a loss of the suprachiasmatic and basilar cisterns. This suggests unequal pressures between the supratentorial and infratentorial compartments. The third finding is any evidence of a posterior fossa mass, obliteration of the superior cerebellar cistern, or obliteration of the quadrigeminal plate cistern caudal to the midbrain. These findings all suggest the presence of increased infratentorial pressure. Do not delay the initiation of antibiotics if meningitis is suspected and a CT scan is indicated before performing an LP. Administer the antibiotics before the patient undergoes CT scanning. Several studies have shown that delays in the initiation of antibiotics are common in the Emergency Department. These delays are often Emergency Physician generated and result from the need for a CT scan prior to LP, waiting for LP results before administering antibiotics, and not giving antibiotics before a patient is transferred to the ward.27–30
COAGULATION DEFECTS An LP is relatively contraindicated in patients with a coagulopathy. This includes hemophiliacs, those on anticoagulants, and patients with thrombocytopenia. An LP can result in a spinal epidural or subdural hematoma with subsequent spinal cord compression. Appropriate replacement of platelets and/or clotting factors should be undertaken prior to attempting an LP if the procedure can be delayed.31 The most experienced Emergency Physician should perform the procedure with a small gauge needle when an immediate LP is indicated in these patients.
FIGURE 115-3. A commercially available LP kit.
EQUIPMENT • • • • • • •
Sterile gloves and gown Face mask and cap 1% lidocaine solution Povidone iodine or chlorhexidine solution LP needles, various gauges and lengths Topical anesthetic agent (e.g., EMLA), optional LP kit
Most of the equipment necessary for performing an LP is available in prepackaged, sterile, disposable, and single-patient use commercial kits (Figure 115-3). These kits usually contain a 20 gauge Quincke spinal needle, syringes, needles (25 gauge and 22 gauge) for local anesthesia, a manometer with a stopcock, sterile drapes, specimen tubes, 1% lidocaine, gauze, brushes for prepping the skin, and bandages. Some kits provide povidone iodine or chlorhexidine swab sticks whereas other kits have a small basin that needs to be filled. The Emergency Physician should become familiar with the kit used at their institution. Additional supplies may be needed to perform the procedure without interruption. For example, some Emergency Physicians prefer a smaller gauge Quincke needle or a nontraumatic needle such as a Sprotte or Whitacre that are not often provided in the commercial kits (Figure 115-4). The use of a 25 gauge spinal needle is
BACTEREMIA Some sources list bacteremia as a contraindication to an LP, especially in children. While there is some suggestion that there may be an association between performing an LP in a bacteremic patient and the later development of meningitis, the risk of this is low. An LP should not be withheld for fear of inducing meningitis. The risk of delaying the diagnosis of meningitis clearly outweighs the small chance of causing meningitis with an LP.32
FIGURE 115-4. The three types of spinal needle tips. The standard Quincke needle has a sharp, beveled end. The Whitacre and Sprotte needles are designed to spread atraumatically, rather than cut dural fibers.
CHAPTER 115: Lumbar Puncture
recommended as it causes a smaller puncture hole and less postprocedural headaches.33–37 It has been suggested that atraumatic needles should be the standard when performing an LP.38,39 In general, it is a good idea to have extra spinal needles, lidocaine, gauze, and skin antiseptic (e.g., povidone iodine or chlorhexidine solution) when performing an LP. There are numerous formulae to determine the LP depth and the length of the spinal needle required.40,41 A reliable formula for estimating the required LP needle length is LP depth (cm) = 1 + [17 × (weight (kg)/height (cm))].41 There are subtle differences among the spinal needles commonly available (Figure 115-4). The standard Quincke needle has a sharp tip with a broad bevel at the end. The Whitaker and Sprotte needles have smaller tips with smaller diameter bevels. The bevel of the Sprotte needle is broader with a rounded tip so as to separate fibers of the dura as opposed to cutting through them. Always remember to keep the bevel oriented parallel to the fibers of the dura when performing an LP regardless of needle style.
PATIENT PREPARATION Explain the risks, benefits, and complications of the procedure to the patient and/or their representative. Obtain a signed informed consent for the procedure. If the patient is a child or minor, ask the
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parents or caregivers whether or not they would like to be present for the LP. There are a variety of different patient positions that can be used to perform the LP (Figure 115-5).33,42,43 Knowledge and proficiency in more than one approach will be useful for the Emergency Physician, especially when encountering a difficult tap. The position of the patient will be chosen based upon the patient’s body habitus, their ability to assume a position, their level of cooperativeness, and Emergency Physician preference. The sitting position is more commonly used in adults than the lateral decubitus position. It is easier to identify the midline and palpate the spinous processes with the patient sitting (Figure 115-5A). The sitting position is particularly useful when patients are obese. While the LP can still be performed in the lateral decubitus position for obese patients, palpating the spinous processes and identifying the midline can be difficult. The measurement of hydrostatic pressure in the CSF is not accurate with the patient sitting. It gives a falsely elevated pressure reading. The lateral decubitus position is often the most comfortable position for the patient (Figure 115-5B). Place the patient with their knees flexed, the upper back arched to spread the interlaminar spaces, and the neck slightly flexed. Ensure that the patient’s shoulders, back, and hips are exactly perpendicular to the stretcher and
FIGURE 115-5. Patient positioning for an LP. A. An adult in the sitting position. B. An adult in the lateral decubitus position. C. An infant restrained in the sitting position. D. A child restrained in the sitting position. E. A child restrained in the lateral decubitus position.
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floor. This will increase the chances of keeping the needle in the midline as it is introduced parallel to the surface of the stretcher. This is particularly important in infants and children where an assistant may be called upon to hold the patient in position. Severe neck flexion is not necessary and can lead to airway obstruction or lack of CSF flow. Children can be placed in the sitting or lateral decubitus position. An assistant can easily maintain neonates and infants in the sitting position (Figure 115-5C). Toddlers and school-aged children can also often be maintained in the sitting position (Figure 115-5D). The lateral decubitus position can be used for any child (Figure 115-5E). It is important to assess the child visually and with pulse oximetry during the procedure. These positions may cause improper neck flexion that can result in respiratory compromise, oxygen desaturation, hypoxemia, and anoxic encephalopathy.44,45 The largest interspinous space is achieved with the patient sitting upright with their hips flexed, leaning forward, and with slight neck flexion based on ultrasonographic studies.45–48 The subarachnoid space must be entered below the termination of the spinal cord that is situated at the lower level of L1 or the body of L2 (Figure 115-6). Identify by palpation the vertebral spinous processes in the midline and the posterior superior iliac spines. The patient can help to determine the midline.179,180 Just ask them if the needle is in the midline. Another option is to draw a line between the spinous process of C7 and the gluteal cleft.49 An imaginary line connecting the posterior superior iliac spines should
Spinal cord L1
Vertebral spine Interspinous ligament
L2
Supraspinous ligament
L3
Needle in subarachnoid space
L4
Ligamentum flavum
Filum terminale
L5 Vertebral body S1
Sacrococcygeal ligament FIGURE 115-6. Midsagittal section of the lumbosacral region with a spinal needle in the L3-L4 interspace. The needle has penetrated the supraspinal ligament, the interspinous ligament, the ligamentum flavum, the dura mater, and the arachnoid mater.
intersect the midline at approximately the L4 spinous process or the L3-L4 interspace. One can select any of the spaces between L2-L3 and L5-S1 to perform an LP. Palpate the intended interspace before prepping the area. Some Emergency Physicians mark the site lightly with a pen or make a small indentation with the hub of a needle. Adjust the bed height so that you can sit in a comfortable position while performing the procedure. Prepare the LP kit. Open the kit using sterile technique and place it on a bedside table. Place povidone iodine or chlorhexidine solution into the basin provided with the kit. Place any additional needles or supplies onto the sterile field. This procedure requires strict aseptic technique. The Emergency Physician should don full sterile and personal protective equipment at this point.50–52 This should include sterile gloves, a sterile gown, a face mask, and a cap. Prepare the stopcock and manometer. The manometer is usually in two pieces that slide together. Insert the manometer into the vertical port of the stopcock. Turn the handle toward the outflow side of the stopcock. In general, the stopcock handle will occlude the port that it points to. Prepare the patient’s back. Clean the skin of any dirt and debris. Apply povidone iodine or chlorhexidine solution using a circular motion from the intended site of entry outward. Allow the solution to completely dry prior to inserting the spinal needle.53 Chlorhexidine solution introduced into the spinal canal can result in arachnoiditis and neurotoxicity. Prepare an area of at least 10 cm in diameter. Most kits include a solid drape and a fenestrated drape. Place the solid drape between the patient’s hips and the bed. Place the fenestrated drape with the adhesive side toward the patient’s back and the opening centered at the desired level for the procedure. Reidentify the anatomic landmarks. Place a finger over the desired interspace to use for the procedure. Place a skin wheal of local anesthetic solution subcutaneously over the desired interspace using a 25 gauge needle. Infiltrate and anesthetize the deeper tissue of the interspace along the projected needle track using the 22 gauge needle. The infiltration of local anesthetic solution, unless contraindicated, should be used in all patients, including neonates and young children. Local anesthetic makes it more likely the LP will be successful.46,47,54 Alternatively, a field block can easily be performed to produce anesthesia of the skin, interspinous ligaments and muscles, and the periosteum. The interspinous ligament and the periosteum are supplied by the recurrent spinal nerves branching off the nerve roots exiting the spinal canal at the same level. Inject local anesthetic solution into the interspinous ligaments, between the spinous processes superior and inferior to the intended puncture site, and on either side of the interspinous space (Figure 115-7).33 A topical anesthetic (e.g., EMLA cream) may be applied over the interspace for 30 to 60 minutes prior to performing the LP if the patient is awaiting a CT scan of the head and antibiotics have been administered. Unfortunately, this only anesthetizes the skin and superficial subcutaneous structures. The patient will still require a local anesthetic injection. It may occasionally be difficult for some patients to remain still and cooperative with the procedure. This can include anxious patients, those with an altered mental status, and small children. These patients may require an intravenous anxiolytic, nitrous oxide administration, or procedural sedation.
TECHNIQUES LATERAL DECUBITUS POSITION AND MIDLINE APPROACH Palpate the intended interspace. Introduce the needle in the middle of the interspace and parallel to the bed. Orient the bevel of
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FIGURE 115-7. Field block for LP anesthesia.
the spinal needle parallel to the longitudinal dural fibers to increase the chances that the fibers will be separated rather than cut by the tip of the needle.55 This has been shown to decrease the incidence of postdural puncture headache.56–58 The bevel should point up or down with the patient in the lateral decubitus position. Angle the needle 10° cephalad, or toward the umbilicus, and advance it slowly. The needle can be held between both index fingers and advanced with the thumbs (Figure 115-8A). Alternatively, it can be guided with a thumb and forefinger near the puncture site while the other hand holds the hub of the needle and advances it (Figure 115-8B). Resistance will usually be felt as the needle penetrates the interspinous ligaments. Stop advancing the needle and remove the stylet frequently to check for the presence of CSF.59 Many describe a characteristic “pop” that is felt when the needle enters the subarachnoid space. The commonly used Quincke needles often decrease or eliminate this sensation. It may also not be felt using atraumatic needles.59 If bone is encountered, withdraw the needle to the subcutaneous tissue, confirm your landmarks, and readvance the needle in the midline. If bone is still encountered, redirect the needle slightly more cephalad and readvance it. Perform the procedure at a different level if still unsuccessful. CSF should flow freely once the subarachnoid space is entered. The rate of CSF flow from the hub of the spinal needle may be slow. The flow rate can be increased by one of the following: ask the patient to Valsalva by gently coughing or bearing down, rotate the spinal needle 90°, or repeat the procedure with a larger bore spinal needle. Attach the stopcock and manometer directly to the needle. Alternatively, use the short extension tubing provided in most kits to connect the needle to the manometer. Hold the hub of the needle firmly between the thumb and index finger and brace your hand against the patient’s back when attaching or removing anything from the spinal needle. This will prevent the needle from advancing or withdrawing. The stopcock handle should point posteriorly and CSF will begin to fill the manometer.
FIGURE 115-8. Two-handed techniques for spinal needle insertion. A. The index fingers guide the tip while the thumbs advance the needle. B. An alternative technique. One hand is placed at the needle tip and the other is at the base of the needle.
Ensure that the manometer hub remains at the level of the needle in order to get an accurate reading if using the extension tubing. Phasic changes with respirations should be noted as the manometer fills. Instruct the patient, or an assistant, to gently extend the patient’s legs to decrease intraabdominal pressure and lower the reading. Normal opening pressure is 70 to 180 mmH2O. Obtain the pressure reading once the CSF flow stops. Turn the stopcock handle toward the needle hub (or patient) to empty the contents of the manometer into the first tube for collection. To continue collection, remove the stopcock or simply remove the manometer and continue collection through the stopcock by pointing the handle toward the manometer port. In general, 1.0 mL of CSF in each of the four tubes should be adequate to perform the CSF analysis. Collect 2 mL in each tube if cytology or antigen testing is necessary. When the samples have been collected, carefully replace the stylet and remove the needle. There is disagreement regarding the use of the spinal needle stylet.181 The literature notes an increased incidence of intraspinal epidermoid tumors after an LP if a stylet is not used. This led to the habit of leaving the stylet in place while inserting the spinal needle
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B
Supraspinous ligament Interspinous ligament
20º
Ligamentum flavum
Erector spinae Subarachnoid space containing cauda equina
Articular process
Body of L3 Epidural space
Dura/arachnoid
FIGURE 115-9. The lateral approach. A. If the patient is in the lateral decubitus position, insert the spinal needle approximately 2 cm below the midline and directed approximately 20° toward the midline, and 10° cephalad. B. Cross section of the spinal column showing the path of the spinal needle during the lateral approach. Notice that it avoids the calcified supraspinal and interspinal ligaments.
to prevent transferring epidermal cells into the spinal canal. Some now recommend removing the stylet after the tip of the spinal needle has been inserted past the epidermis.46,60 This method has shown to result in a greater success rate when performing an LP. Reinserting the stylet into the spinal needle is potentially problematic. Many will hold and stabilize the spinal needle with one hand and reinsert the stylet with the other hand. This risks a potential needlestick injury. The author inserts the stylet with one hand without using the other hand to stabilize the spinal needle. Reinserting the stylet prior to removal of the spinal needle has been shown to decrease the incidence of the post-LP symptoms of dizziness, headache, nausea, and tinnitus.61 The method of using the stylet is left to Emergency Physician preference.
SITTING POSITION AND MIDLINE APPROACH Place the patient sitting on the edge of the bed. Ask the patient to flex their lower back and lean forward onto some support, such as an assistant or bedside stand, in order to open the interlaminar spaces in the lumbar area. Orient the bevel of the needle laterally (to the left or right). The remainder of the procedure is the same as previously described.
LATERAL APPROACH The lateral approach may be useful in avoiding the calcified supraspinous and interspinous ligaments often encountered in elderly patients. This approach may be performed with the patient in the lateral decubitus position or the sitting position. Though it is less commonly used than the midline approach, it is a good idea for the Emergency Physician to become familiar with this technique as an alternate approach if the midline approach has failed. This may prove easier in the patient who has had multiple previous midline LPs.
Position the patient and select an appropriate interspace. Cleanse, drape, and anesthetize the area as previously described. Insert the spinal needle 1.5 to 2.0 cm lateral to the midline. The needle can approach from either side (left or right) if the procedure is being performed in the sitting position. Approach from the inferior side if performing the LP in the lateral decubitus position (Figure 115-9A). Direct the needle 10° cephalad and approximately 20° to the midline. This angle will direct the needle through the erector spinae muscles and lateral to the supraspinous and interspinous ligaments. The needle will penetrate the ligamentum flavum, the dura, and then the subarachnoid space (Figure 115-9B). If bone is encountered, partially withdraw the needle and redirect it at the same angle toward the midline but slightly more cephalad. The remainder of the procedure is as described previously.
LP IN INFANTS AND CHILDREN Performing an LP in an infant or child is similar to that of an adult. Place the patient in the lateral decubitus position or the sitting position. Place the neck in midflexion in the lateral decubitus position. Severe flexion of the neck does not facilitate the procedure and can result in the lack of CSF flow or airway obstruction. Hypoxemia has been reported during LP in infants. The increased intraabdominal pressure caused by flexing the knees into the abdomen may lead to compression of the diaphragm, ventilation-perfusion mismatch, and hypoxemia.62 For this reason, the sitting position or modified lateral decubitus position (hips only flexed to 90°) is preferred.63 Preoxygenation with 100% oxygen via face mask for 2 to 5 minutes may prevent hypoxemia.64 Consider the use of continuous pulse oximetry in infants and young children undergoing an LP. Some authors advocate the use of a butterfly needle and using the tubing as a manometer to get a general idea of the opening pressure.
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The use of nonstyletted needles, however, may occasionally result in the implantation of cells and a subsequent epidermoid tumor. In some low ICP syndromes, CSF may fail to flow during the procedure and gentle suction with a 1 mL syringe can be used. Local anesthesia should be used in all patients, even in neonates. There is evidence that pain perception is present even in premature neonates.65 The use of local anesthetic is often omitted in the neonate and young infant, possibly in fear of obscuring anatomical landmarks. Pinheiro et al. studied the success rate of LP in neonates given local anesthetic, the amount of struggling during lidocaine injection, and the amount of struggling during spinal needle insertion.66 They found that local anesthesia did not alter the success rate of the procedure and led to a decreased amount of struggling during spinal needle insertion. The use of a eutectic mixture of local anesthetics (EMLA) cream or similar topical anesthetic is common and effective for venipuncture in children. It also can be used successfully before LP in children and adults.67,68 EMLA has been shown in some studies on adults to be more effective than lidocaine infiltration.69,70 The major disadvantage of EMLA cream is that it requires application for a minimum of 30 minutes before the procedure is performed. In general, it is more effective if it stays on longer. It also does not anesthetize the deeper tissues and local infiltration is still required. Procedural sedation is usually reserved for those children getting routine LPs for intrathecal chemotherapy. If absolutely necessary, procedural sedation can be used while performing a diagnostic LP. Procedural sedation should not be used unless the child has a normal mental status and is hemodynamically stable. The decision regarding procedural sedation must be considered on a case-bycase basis.
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of overweight (BMI = 25 to 29.9) and obese (BMI ≥ 30) patients.71 Under this approach, patients in whom an LP is not predicted to be difficult would have it attempted initially with the landmark palpation method, reserving US guidance for failures. The final approach uses US guidance initially for all patients, regardless of their BMI or the predicted ease of an LP. US can be used to visualize structures and mark the point of needle insertion. It can also be used to visualize the deep soft tissue structures, allowing the Emergency Physician to estimate the depth that the needle needs to be inserted to enter the subarachnoid space.79 A high-frequency linear US probe is the transducer of choice. In patients with a higher BMI, the linear probe may not allow visualization to the depth required. In these cases, use a lower-frequency US probe, generally a curvilinear array. A pen or surgical skin marker is needed to mark the skin at the point of needle insertion. Surgical skin markers have the advantage of using scrub-resistant, non-smearing ink. Both transverse and longitudinal midline images centered over the lumbar spine are utilized.71,72 Ferre and Sweeney indicated a preference for the paramedian longitudinal view.72 This view was felt to allow better visualization of deep soft tissue structures such as the ligamentum flavum and dura mater. In the transverse view, the spinous process causes a shadow that extends from near the top to the bottom on the monitor screen (Figure 115-10).73,77 In the longitudinal view, the distal tips of the spinous processes are seen as a series of echogenic convexities (Figure 115-11).
ULTRASOUND-GUIDED LP For the past several decades, Anesthesiologists have been using ultrasound (US) to assist in various spinal procedures. More recently, Emergency Physicians have reported on the use of US to assist in performing an LP or to evaluate spinal anatomy.71–75 Peterson and Abele described two patients in whom multiple attempts at landmarkguided LP were unsuccessful. US-guided LP was performed easily and was successful in each patient. The authors concluded that the technique has great potential as a time-saving tool.73 Nomura and colleagues performed a randomized, double-blind study comparing LP using landmarks identified by palpation versus those identified by US.75 The use of US significantly reduced the number of failures in all patients and improved the perceived ease of the procedure in obese patients. A group of Radiologists studied US guidance for LPs in children.76 They found US superior to fluoroscopy as it allows three-dimensional guidance in real time and provides visualization of soft-tissue structures. With the increasing availability of US machines in Emergency Departments, ultrasonography is more readily available to assist the Emergency Physician in performing many procedures including an LP.71,72 US can visualize both superficial and deep tissue structures. Emergency Physicians who consider using US in assisting with an LP should be properly trained in the use and theory behind US before attempting to use it in the clinical setting. There are three possible approaches to establishing the indications for the use of US to guide an LP. US guidance can be used for an LP when the traditional landmark-guided approach has failed. This approach may result in more patients having multiple attempts at an LP. US guidance can be used as the initial method in patients predicted to have a higher failure rate with landmarkguided LP. This includes patients with spinal landmarks that are difficult or impossible to palpate.72,77,78 The landmarks are increasingly difficult to palpate in the body mass index (BMI) categories
FIGURE 115-10. US image of the lumbar spine in the transverse view. The spinous process (arrow) causes a shadow that extends from the top to the bottom of the monitor screen.
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FIGURE 115-12. The US probe is oriented transversely across the lumbar spine. A mark is placed on each side of the US probe’s midpoint.
FIGURE 115-11. US image of the lumbar spine in the longitudinal view. The distal tips of the spinous processes are seen as a series of echogenic convexities (arrows).
Place the patient into the position they will be in during the LP, whether the lateral decubitus position or sitting upright. It is important that the patient be in the exact position, such as with spinal flexion and their knees drawn up, that will be used during the LP. Any change in patient position between the time of the US and the LP could change the location of the landmarks and decrease the likelihood of success. Use US to locate the entry site of the spinal needle. Using the transverse view at the level of the iliac crests, move the US probe until the shadow caused by the spinous process is centered on the monitor screen (Figure 115-10). Use the skin marker to place a mark on each side of the US probe, exactly at its midpoint (Figure 115-12). When these two lines are connected, they will form a single line that marks the midline of the spine. Rotate the US probe 90° to a midline longitudinal view. Move the US probe until the tops of two adjacent spinous processes are seen, with the gap between them located in the center of the screen (Figure 115-11). Again, make two marks on the patient’s skin, one on each side of the US probe at its midpoint (Figure 115-13). These two marks, when connected, will form a single transverse line that indicates the center of the gap between adjacent spinous processes. Set aside the US probe. Connect the two pairs of skin marks to form two lines that intersect at a right angle (Figure 115-14). Their intersection marks the site of needle entry (Figure 115-14). Clean and prep the patient’s skin and perform the LP as described previously.
FIGURE 115-13. The US probe is oriented longitudinally along lumbar spine. A mark is placed on each side of the US probe’s midpoint.
FIGURE 115-14. Two pairs of marks are obtained. Their intersection (purple dot) marks the spot for the spinal needle entry.
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RISK FACTORS FOR TRAUMATIC OR UNSUCCESSFUL LP There are numerous risk factors for obtaining a traumatic or unsuccessful LP.60,80 It is important to recognize these, as traumatic or unsuccessful attempts may cause diagnostic ambiguity and lead to unnecessary antibiotic use, hospitalization, and patient discomfort. In the setting of a high likelihood of a difficult LP, steps may be taken to minimize patient discomfort and maximize the chance of a successful LP. Have the most experienced Emergency Physician perform the procedure. If there is a high likelihood of a traumatic LP and there is a high suspicion of a SAH, consider the use of US or fluoroscopic guidance. Emergency Physicians should never delay administering antibiotics, or other potentially lifesaving treatment, because an LP may appear difficult. In adults, the inability to either visualize or palpate the spinous processes is predictive of a difficult LP. The inability to visualize the spinous processes is associated with an increased risk of a traumatic LP.80 As described previously, the use of bedside US can assist in the identification of the spinous processes. There are several risk factors in children associated with an unsuccessful or traumatic LP.60 These include patient-related factors such as young age and inability to visualize the spinous processes, physician factors such as less experience performing LP, and procedural factors such as no local anesthetic use, patient movement, and advancement of the spinal needle with the stylet in place.60 Physicians have traditionally been taught to keep the stylet in place as the spinal needle is advanced into the subarachnoid space as this will avoid the introduction of epidermal cells into the subarachnoid space and the subsequent development of an epidermoid spinal canal tumor. However, the stylet-out technique has not been linked to this complication as long as the stylet is used as the needle penetrates the skin.60 The greatest benefit of stylet removal appears to occur in young infants when the Emergency Physician is less likely to feel the spinal needle penetrate the dura. The stylet-out technique allows for continuous monitoring of penetration into the subarachnoid space by direct visualization for CSF return.
AFTERCARE Clean the excess povidone iodine or chlorhexidine from the patient’s back and apply a dressing or bandage to the puncture site. Immediately place the patient supine to decrease the potential for a postdural puncture headache (PDPH) and decrease the risk of local bleeding. Recumbent positioning will decrease the postural headache that sometimes follows LP, but it has not been shown to decrease the incidence of PDPH.
COMPLICATIONS The use of proper technique is essential when performing an LP. It is also important that the Emergency Physician is aware of potential complications, how to recognize them, and how to manage the complications that can result from an LP. Refer to the article by Evans for a complete review of LP complications.81 The PDPH is the most common complication and cerebral herniation is the most immediately life-threatening complication. Localized cellulitis, dural abscesses, discitis, and localized bleeding are also potential complications.
CEREBRAL HERNIATION The most serious complication that may result from an LP is brain herniation or coning.14 Theoretically, if a large pressure gradient exists between the cranial and lumbar compartments, herniation
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across the tentorial incisura or foramen magnum may occur after removal of CSF from the lumbar area. Patients with increased ICP secondary to intracranial mass lesions, cerebral edema, and acute hydrocephalus are at greater risk for cerebral herniation or coning. Herniation has also been known to occur in patients with meningitis. For many years, the role of LP in precipitating brain herniation has been the subject of debate. Several studies suggest that an LP is relatively safe in the patient with increased ICP.82–84 However, each individual patient’s risks and benefits must be considered before proceeding. Herniation has resulted from an LP in patients with meningitis and SAH.85–87 The actual role that an LP has in precipitating or facilitating the process of herniation is not known.85 Patients with decorticate or decerebrate posture, focal neurologic signs, or no response to pain should receive antibiotics but not a LP; this is true even in the face of a normal CT in suspected cases of meningitis.85,87 Deterioration after an LP has been reported in patients with a SAH. Fortunately, it is a rare outcome as a result of an LP. A CT scan should be obtained before performing an LP if there is a suspicion for a SAH.88,89
POSTDURAL PUNCTURE HEADACHE The PDPH is the most common complication of an LP. It is thought to be the result of continued CSF leakage at the puncture site. The reason why this causes a headache is unclear.90 It is thought that the lower CSF pressure induced by the leakage causes the brain to “sag.” This leads to traction on pain-sensitive structures in the brain such as the dura, nerves, and bridging veins. Intracranial venous dilation and increased brain volume may lead to a neurohumoral response identified as pain. The headache begins within 24 hours of the procedure in 65% of cases and within 48 hours in 90% of cases.91 Delayed development of a PDPH 5 to 14 days after the procedure has been reported. The headache typically resolves within 7 days. It has been reported to last several months in rare individuals. The headache is usually located in the frontal or occipital area. It may vary in intensity. The PDPH is usually described as bilateral pressure that is throbbing or achy and improves with supine positioning. Associated symptoms may include nausea, vomiting, neck stiffness, auditory symptoms, and vestibular symptoms.91 The incidence of PDPH has been reported to be anywhere from 1% to 70%. The wide range is most likely due to the fact there are several identifiable risk factors that influence its development. Age and gender play a significant role.91–93 The highest incidence occurs in 18 to 30 year olds. There seems to be a decreased incidence after the age of 60, the reason for which is unknown. The type of needle and its diameter also influence the development of a PDPH.34–38 This is based upon the amount of trauma and the size of the rent it makes in the dura. Smaller diameter needles and atraumatic needles lower the incidence of PDPH. However, a 22 or larger gauge needle must be used to determine the opening pressure and to collect samples in a timely fashion when performing a diagnostic LP.94 The bevel orientation should be parallel to the longitudinal dural fibers when using a Quincke needle. This significantly reduces the incidence of PDPH.58,95–97 The use of an atraumatic needle may also decrease the incidence of PDPH.98,99 These needles are designed to separate rather than shear the dural fibers. Replacement of the stylet before removing the spinal needle has been shown to decrease the incidence of PDPH.100 Repeated dural punctures have been associated with an increase in the incidence of PDPH.101 Other nonproven risk factors for a PDPH include psychogenic factors, the rapidity of CSF withdrawal, race, patient positioning, and hydration status. Bed rest for 24 hours was often widely
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recommended. However, it has not been shown to decrease the incidence of PDPH.102–104 Other studies have shown bed rest to increase the risk of PDPH.105,106 Early ambulation does not increase the incidence of PDPH.107 Dehydration was once felt to impair the patient’s ability to produce CSF to compensate for the leaking CSF. Dieterich and Brandt found that the incidence of PDPH was independent of daily fluid intake.108 They postulated that it is the closure of the dural defect and not the CSF loss that is the critical factor in the termination of the PDPH. Supine positioning can provide some symptomatic relief for initial or mild PDPHs. A single 300 mg dose of oral caffeine may provide transient relief.109 While offering no advantage over caffeine, an oral dose of theophylline can also be given. Administer 500 mg of intravenous caffeine, or 5 to 6 mg/kg of intravenous aminophylline, for more severe headaches. In the only study to date describing the use of intravenous caffeine, Sechzer and Abel reported an approximately 70% success rate in treating PDPH.110 A more recent study suggests that intravenous caffeine administered prophylactically may minimize the incidence of PDPH.111 There is some promise in the use of triptans.112,113 The use of cosyntropin, an ACTH analog, has shown promise in the treatment of PDPH.114,115 An occipital nerve block may resolve a PDPH.116,117 A more definitive but invasive treatment for the PDPH is the epidural blood patch.118 This procedure is to be performed by an Anesthesiologist. It involves injecting 10 to 20 mL of autologous blood into the epidural space at the level of the previous LP. The blood acts to tamponade any further CSF leakage and allows healing of the dural rent. Epidural blood patching is successful in 85% of patients after one injection and about 98% of patients if a second blood patch is required.119–121 Epidural blood patching should be performed no sooner than 24 hours after the LP. Complications of the blood patch include back pain, paresthesias, radiculopathies, and weakness; all of which are transient. A rare
complication is the spinal subdural hematoma.122 Other modalities for PDPH relief that have been used but not widely studied are epidural saline injections, dextrose injections, gelatin injections, and epidural morphine.
INFECTIONS Local infections including cellulitis, abscesses (lumbar epidural or spinal cord), and discitis can result from an LP. Performing an LP through an area with a local infection, such as a cellulitis or an abscess, can introduce bacteria into the CSF and lead to meningitis. Contamination of the needle by airborne pathogens can also occur. Always wear a sterile gown and gloves, a mask, and a cap while performing an LP.50 It is possible for the Physician’s oral flora to contaminate the field and equipment, resulting in an iatrogenic meningitis.50–52 It was once thought that an LP could induce meningitis in a bacteremic patient. Further studies have shown this idea to be unfounded.123–125 Bacteremia is not a contraindication to performing an LP. Proper cleaning and disinfecting of the skin, avoiding infected areas with the spinal needle, and using aseptic technique will minimize but not eliminate any risk of infection.
HEMORRHAGE A traumatic LP is a common occurrence. Up to 72% of LPs have anywhere from 1 to over 50 red blood cells.126 This is a common and usually uncomplicated occurrence in patients with a normal coagulation profile. Traumatic LPs can result in a spinal epidural or spinal subdural hematoma in patients with or without coagulation abnormalities.127–131 Epidural hematomas most likely result from needle trauma to the internal vertebral plexus or radicular vessels (Figure 115-15).126 The radicular vessels course down the length of each nerve root. It has been suggested that the bevel of the spinal
External vertebral venous plexus Nerve roots forming cauda equina
Internal vertebral venous plexus
Rediculomedullary vein Dura L4 Spinal needle
Arachnoid
Lumbar vein
Internal vertebral venous plexus FIGURE 115-15. Illustration of the spinal cord and the potential sources of spinal needle-induced bleeding. Note, however, that the correct path of the spinal needle should usually avoid the internal vertebral venous plexus.
L5
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needle can induce trauma and bleeding to these vessels much like they produce paresthesias when touching the nerve roots. Spinal epidural hematomas, if large enough, can result in a cauda equina syndrome.132 Subdural or SAH is a rare but catastrophic complication in patients with or without a coagulopathy.130 Edelson et al. recommend that the procedure be performed only if absolutely necessary in patients with a thrombocytopenia.133 Platelets should be transfused prior to an LP in patients with platelet counts less than 20,000 or if platelet counts are dropping rapidly. The most skilled Emergency Physician should perform the LP using a 22 gauge (or smaller) needle.133 Patients should be observed after the procedure for the development of neurological signs suggesting a hematoma. Such signs include paraplegia, lower extremity weakness, sensory deficits, or incontinence. Another rare bleeding complication is an intracranial subdural hematoma.134,135 This may result from the same mechanism causing a PDPH, namely the downward displacement of the brain from decreased CSF volume and persistent leakage after an LP. This may occasionally cause tearing of the bridging veins and lead to a unilateral or bilateral subdural hematoma. Suspect this diagnosis when a headache sounding like a PDPH lasts for more than a week, is no longer postural in nature, or returns after initially improving.136
Prevent secondary injury by always inserting the stylet into the spinal needle before removing it.61 Withdrawing the spinal needle without the stylet can result in the aspiration of a lumbar nerve root or arachnoid tissue into the epidural space. If this occurs, the patient may require a laminectomy to replace the nerve root or arachnoid tissue. The reinsertion of the stylet will also decrease the incidence of post-LP symptoms (e.g., dizziness, headache, nausea, and tinnitus).61 It is now common for adolescents and adults to have tattoos on their lower back. It is recommended to perform an LP in an area void of tattoo ink, at a higher or lower interspace, or nicking the skin with a needle or scalpel prior to inserting the spinal needle.144,145 All these techniques avoid the spinal needle penetrating through the tattoo ink. The tattoo ink may contain substances that can be irritating or toxic if introduced into the spinal canal.
MISCELLANEOUS COMPLICATIONS
Normal CSF pressure ranges from 70 to 180 mmH2O in adults and from 50 to 80 mmH2O in infants and children. Note that many manometer kits use cmH2O on the demarcations whereas results are commonly interpreted in mmH2O. Elevated CSF pressure may be seen in bacterial meningitis, viral meningitis, brain abscesses, tuberculous meningitis, fungal meningitis, encephalitis, meningeal carcinomatosis, SAH, pseudotumor cerebri, and Guillain–Barré syndrome. It may be falsely elevated when the patient is tense or creating a lot of intraabdominal pressure by flexing their knees into the abdomen. The pressure will also be falsely elevated if the patient is in a sitting position. Although CSF pressure is not routinely recorded in infants and children (most likely because they are often crying, struggling, or difficult to hold), it should be recorded whenever possible. Low CSF pressure may be the result of a spinal root obstructing the flow of CSF into the needle or obstruction of flow from a spinal mass. A novel device to measure pressure is the Compass LP (Mirador Biomed, Seattle, WA). This device is a single patient use and disposable unit that attaches to the spinal needle. It provides a digital readout of the CSF pressure. Further research is required before this device replaces the standard manometer.
Neuropathies involving cranial nerves III, IV, V, VI, VII, and VIII have been reported. They most likely result from traction on the nerves caused by low ICP after the LP. Typical complaints may include visual and auditory symptoms. Epidural fluid collections of CSF after an LP can be significant.137 They usually resolve spontaneously with time but can compromise the thecal sac if large enough. Mild low back pain is a common complaint that results from the local trauma of the needle tract. Transient dysesthesias are fairly common, resulting from spinal needle contact with the nerve roots. A spinal needle that passes beyond the subarachnoid space into the annulus fibrosis can cause disc herniation. This can also result in a discitis and vertebral collapse.138 Intraspinal epidermoid tumors are composed of welldifferentiated stratified squamous epithelium surrounding a mass of caseous substance formed by the desquamation of epidermal tissue. They are often congenital but may result from the introduction of epidermal fragments into the spinal canal. This may occur if the stylet of the needle is not used. Spinal epidermoid tumors may present months to years after an LP.139–142 A dry tap is often the result of lateral displacement of the spinal needle. Maintain the spinal needle in the midline while it is being advanced. Not penetrating deep enough with the spinal needle can also result in a dry tap. This is especially true in obese patients that may require long, 7 to 10 in., spinal needles to gain access to the subarachnoid space. It has been suggested that the standard 3.5 in. spinal needle is adequate for 97% of patients.143
CSF INTERPRETATION Proper interpretation of the CSF is an important skill for the Emergency Physician who performs the LP. Tables 115-1 and 115-2 list the normal CSF values and the CSF values in a variety of different medical conditions.146,147
CSF PRESSURE
CELL COUNTS AND DIFFERENTIAL A variable amount of white blood cells (WBCs) may be normally present in the CSF depending upon the age of the patient.148 Neonates may have up to 32 WBCs/mm3 with 60% polymorphonuclear leukocytes (PMNs). Infants 4 to 8 weeks of age may
TABLE 115-1 Normal CSF Values White blood cell count (WBC/mm3) Glucose (mg/dL) CSF/blood glucose ratio Normal ratio Abnormal ratio Protein (mg/dL)
Preterm infant 9 (range 0–32) 57% PMNs 24–63 (mean 50)
Term infant 8 (range 0–22) 61% PMNs 34–119 (mean 52)
Child 0–7 0% PMNs 40–80
Adult 0–5 0% PMNs 50–80
55%–105% 6 mm in length is over 120 beats/min. FHR serves as an important prognostic indicator. Rates less than 90 beats/min are associated with a high risk of spontaneous abortion.
■ CROWN RUMP LENGTH The crown rump length (CRL) is the most accurate sonographic measurement for gestational dating between 6 and 12 weeks. It is accurate within ±4.7 days for gestational dating. At 6 weeks of gestational age it is not possible to differentiate the crown from the rump. The embryonic pole length is used for the CRL measurement. By 8 weeks a true CRL measurement can be determined. Obtain the longest measurement of an unflexed fetus and do not include the yolk sac (Figure 130-21). The gestational age is calculated by the following equation: gestational age (weeks) = CRL (mm) + 6.5.
■ CORPUS LUTEUM CYST The corpus luteum is a normal physiologic structure found within one of the ovaries during pregnancy. It is unilocular and thinwalled. The sonographic appearance of a corpus luteum is highly variable. It can appear as a hypoechoic, hyperechoic, or isoechoic structure. Power Doppler mode shows the corpus luteum has increased blood flow at the periphery that is described as a “ring of fire” (Figure 130-22). The ring of fire is also visible with an ectopic pregnancy.
FIGURE 130-22. Corpus luteum cyst with the ring of fire visualized on Power Doppler mode.
B FIGURE 130-23. Sagittal view of an early pregnancy failure by TVS. A. The gestational sac is 13 mm in diameter (dotted line) without a visible yolk sac. B. An irregular gestational sac.
■ EMBRYONIC DEMISE OR EARLY PREGNANCY FAILURE Definitive diagnosis of an early pregnancy failure requires serial US examinations. A blighted ovum is a failed pregnancy in which the embryo failed to develop within a gestational sac of sufficient size that an embryo should be visible. There are several sonographic findings that can suggest early pregnancy failure. The earliest sign of early pregnancy failure is a gestational sac without a yolk sac or embryo (Figure 130-23A). An empty gestational sac with a MSD ≥20 mm and no evidence of an embryo or yolk sac by TVS is highly suggestive of an embryonic demise. Other predictors of embryonic demise are: a gestational sac >10 mm in diameter by TVS without a yolk sac, a gestational sac >20 mm in diameter by TAS without a yolk sac, a gestational sac >18 mm in diameter by TVS without a fetal pole, or a gestational sac >25 mm in diameter by TAS without a fetal pole. Other signs suggestive of early pregnancy failure include a gestational sac that is irregular in shape, distorted, or collapsed (Figure 130-23B). A gestational sac positioned low in the uterine cavity or surrounded by a thin (6 mm in diameter) is predictive of embryonic demise. A calcified yolk sac is associated with an adverse pregnancy outcome. The absence of fetal cardiac activity in an embryo
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A
FIGURE 130-24. Embryonic demise. Note the absence of fetal cardiac activity on M-Mode (Courtesy of Sam Hsu, MD).
with a crown rump length >6 mm is an indicator of embryonic demise (Figure 130-24). Embryonic bradycardia is associated with a poor prognosis. Fetal heart rates 5 mm are associated with an 80% rate of eventual fetal demise.
■ SPONTANEOUS ABORTION A spontaneous abortion is the most common complication of first trimester pregnancy and occurs in approximately 20% of clinically apparent pregnancies.15 An empty uterus with a clear midline echo occurs on US after a complete spontaneous abortion. An incomplete abortion is visible on US as irregular echogenic material within the uterine cavity (Figure 130-25A) or a thickened midline stripe (≥10 mm wide) within the uterine cavity (Figure 130-25B). These both represent retained products of conception.
■ SUBCHORIONIC HEMORRHAGE A subchorionic hemorrhage is bleeding between the chorion and the uterine endometrium. It can cause sudden pelvic pain or vaginal bleeding. The overall incidence in pregnancy is 1.3%. It results in the chorionic membrane separating and elevating from the decidua vera (endometrium) by a hematoma or clot. The acute hemorrhage appears hyperechoic or isoechoic. The hematoma becomes hypoechoic or anechoic as it undergoes liquefaction during the subsequent 1 to 2 weeks (Figure 130-26). There is an increased risk of miscarriage, stillbirth, and preterm labor in patients with a subchorionic hemorrhage. In a retrospective study done by Bennett et al., the overall pregnancy loss rate was 9.3%.16 This was found to increase with increasing maternal age and decreasing gestational age. The prognosis depends upon the size of the subchorionic hemorrhage. Small and medium sized hemorrhages, up to approximately 50% of the gestational sac circumference, have a spontaneous abortion rate of 9%. Hemorrhages larger than 50% of the gestational sac circumference have a spontaneous abortion rate of 18.8%. Hemorrhages >40% of the volume of the gestational sac are associated with spontaneous abortion rates of 50%.
B FIGURE 130-25. Sagittal view of an incomplete spontaneous abortion by TVS. A. Irregular echogenic material in the endometrial canal without evidence of a fetus. B. Thickened endometrial stripe (dotted line) without evidence of a fetus.
general population, accounting for approximately 8% of all pregnant patients seen in the ED.18,19 Approximately 40% of ectopic pregnancies are missed or not diagnosed during the initial ED evaluation. Ectopic pregnancy is still the leading cause of pregnancy-related deaths during first trimester of pregnancy.20 Clinical
■ ECTOPIC PREGNANCY It is estimated that approximately 2% of all pregnancies are ectopic pregnancies in the United States.17 The prevalence of ectopic pregnancy in the ED is much higher compared with the
FIGURE 130-26. Sagittal (left) and coronal (right) views of a pregnant uterus by TAS showing a subchorionic hemorrhage (SCH) (Courtesy of Sam Hsu, MD).
CHAPTER 130: Ultrasound in Pregnancy
criteria alone are not sufficient to distinguish between a patient having a spontaneous abortion and an ectopic pregnancy. Pelvic US is the diagnostic test of choice in the evaluation of a patient with a possible ectopic pregnancy. The risk of heterotopic pregnancy in the general population is 1 in every 30,000 pregnancies. The risk increases in women undergoing fertility treatments to 1 in every 5000 pregnancies or greater. The discriminatory zone is the β-hCG level at which an IUP should be seen by pelvic US. This level generally is between 1000 and 2000 mIU/mL by TVS and between 4000 and 6500 mIU/mL by TAS. Approximately 38% of patients with a confirmed ectopic pregnancy had a β-hCG level 70% isopropyl alcohol solution/swabs • 3% hydrogen peroxide solution
PATIENT PREPARATION Inform the patient of the need to measure the pressure in their eye. Explain that an instrument will contact their tear film directly over the cornea. Reassure the patient that tonometry is not painful. It is not necessary to have the patient sign a consent form, as tonometry is part of a routine eye examination. One may choose to document the discussion with the patient for completeness. Remove all contact lenses before the instillation of any topical ocular anesthetic agent or fluorescein. Measuring IOP through a contact lens is unreliable. The fluorescein dye will permanently stain contact lenses and clothing. Instill one drop of a topical ophthalmic anesthetic agent in both of the patient’s eyes. The contralateral eye is used as the control, even if only one eye is of concern. Topical ophthalmic anesthetic
DIGITAL PALPATION Digital palpation is not as accurate as applanation tonometry. Digital palpation has been an informal means of judging IOP, as there is a built-in comparison with the contralateral eye. Studies examining this technique have shown inexperienced examiners can improve their accuracy with a short training session to within 5 mmHg of the actual IOP 88% of the time.6 Digital palpation should not be attempted if there is any potential for a ruptured globe. Place the patient supine or in a reclined position. Ask the patient to close their eyes and look straight ahead through the closed eyelids. Stand next to the patient’s torso and facing them. Place the right thumb over the patient’s left eye and left thumb over the patient’s right eye. Place the remaining fingers of both hands on the patients’ temples for stability. Apply gentle alternating pressure to each globe. The Emergency Physician should be able to ascertain any difference in pressure between the two eyes using the patient’s contralateral eye as a control. The Emergency Physician may also gently palpate their own globe as a normal control. This qualitative measurement is often sufficient to determine a significantly elevated IOP.
SCHIØTZ TONOMETRY The Schiøtz tonometer estimates IOP by measuring the indentation of the globe caused by a known weight.7 The Schiøtz tonometer is a sturdy, low maintenance, and affordable instrument. It is gravity dependent and requires the patient to be supine or have their head fully extended to get an accurate reading. The Schiøtz tonometer case contains the Schiøtz tonometer, a calibration scale, weights, and a calibration platform (Figure 156-4). The tonometer consists of a plunger and a hammer device connected to a needle (Figure 156-5). The needle is calibrated to a scale, with each unit measuring 0.05 mm on the scale. The plunger, the hammer, and the needle weigh 5.5 g. This can be increased to 7.5, 10, or 15 g by adding known weights to the tonometer. The weighted plunger is heavy and has a large contact area that causes significant indentation of the cornea with each measurement. The
CHAPTER 156: Intraocular Pressure Measurement (Tonometry)
FIGURE 156-4. The contents of the Schiøtz tonometer case.
more weight it takes to move the needle on the scale or indent the cornea, the higher the IOP. The scale reading is converted to IOP in mmHg by a conversion chart supplied with each Schiøtz tonometer (Figure 156-4). Place the patient supine or sitting with their head fully extended. Ensure that the patient is comfortable. A tight collar, flexed neck, breath-holding, squeezed eyelids, looking toward the nose, or accommodation results in a falsely elevated reading. Place two drops of a topical ophthalmic anesthetic agent onto each eye.
A
1035
Calibrate the tonometer by placing the footplate of the plunger on the platform provided in the case (Figures 156-4 & 156-5). The scale reading must be “0” while the footplate is on the platform. The instrument requires repair if it does not read zero while on the platform. Instruct the patient to look at a fixation target directly overhead and to open both eyes as wide as possible. Spread the eyelids with the nondominant index finger and thumb if necessary. Grasp the Schiøtz tonometer by its handle. Ensure that the fingers holding the eyelids open are pushing on the orbital rim and not the globe, falsely elevating the IOP. Place the footplate of the Schiøtz tonometer directly over the pupil and gently lower it onto the tear film (Figure 156-6). Note the reading on the scale. Add more weight if the scale reading is less than three units. Do not push down on the cornea with the Schiøtz tonometer. This will cause a false elevation in the IOP reading. Repeat the measurement several times or until three readings are within 0.5 scale units. Convert the scale reading to IOP with the conversion chart (Table 156-1).8 Clean the tonometer immediately after each use. Clean the barrel with two pipe cleaners, the first soaked in 70% isopropyl alcohol and the second one dry. Clean the plunger with an alcohol swab. Allow the instrument to air dry 1 to 2 minutes before being used in the contralateral eye so that the alcohol evaporates and is not transferred to the corneal surface.10
GOLDMANN (APPLANATION) TONOMETRY The Goldmann tonometer is considered the clinical standard for measuring IOP. This method of tonometry is based on the ImbertFick principle.4 It states that the pressure inside an ideal dry, thinwalled sphere equals the force necessary to flatten its surface divided by the area of the flattening (P = F/A; where P = pressure, F = force,
B Scale
Weight
Plunger Indicator dial or needle
Accessory weight
Handle
Footplate
Sleeve
Plunger assembly
Footplate
Test block or platform Test block or platform
FIGURE 156-5. The Schiøtz tonometer. A. Schematic of the tonometer. B. Schematic of the plunger assembly.
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SECTION 12: Ophthalmologic Procedures TABLE 156-1 The Schiøtz Tonometer Scale Tonometer reading 5.5 g load 7.5 g load 0.0 41.5 59.1 0.5 37.8 54.2 1.0 34.5 49.8 1.5 31.6 45.8 2.0 29.0 42.1 2.5 26.6 38.8 3.0 24.4 35.8 3.5 22.4 33.0 4.0 20.6 30.4 4.5 18.9 28.0 5.0 17.3 25.8 5.5 15.9 23.8 6.0 14.6 21.9 6.5 13.4 20.1 7.0 12.2 18.5 7.5 11.2 17.0 8.0 10.2 15.6 8.5 9.4 14.3 9.0 8.5 13.1 9.5 7.8 12.0 10.0 7.1 10.9 10.5 6.5 10.9 11.0 5.9 9.0 11.5 5.3 8.3 12.0 4.9 7.5 12.5 4.4 6.8 13.0 4.0 6.2 13.5 5.6 14.0 5.0 14.5 4.5 15.0 4.0 15.5 16.0 16.5 17.0 17.5 18.0 18.5 19.0 19.5 20.0
10 g load 81.7 75.1 69.3 64.0 59.1 54.7 50.6 46.9 43.4 40.2 37.2 34.4 31.8 29.4 27.2 25.1 23.1 21.3 19.6 18.0 16.5 15.1 13.8 12.6 11.5 10.5 9.5 8.6 7.8 7.1 6.4 5.8 5.2 4.7 4.2
15 g load 127.5 117.9 109.3 101.4 94.3 88.0 81.8 76.2 71.0 66.2 61.8 57.6 53.6 49.9 46.5 43.2 40.2 38.1 34.6 32.0 29.6 27.4 25.3 23.3 21.4 19.7 18.1 16.5 15.1 13.7 12.6 11.4 10.4 9.4 8.5 7.7 6.9 6.2 5.6 4.9 4.5
FIGURE 156-6. The Schiøtz tonometer positioned on the cornea.
Use the tonometer scale reading and the weight applied to the plunger (gram load) to determine the IOP reading in mmHg.
and A = area). The Goldmann tonometer determines the force necessary to flatten or applanate an area of the cornea 3.06 mm in diameter. The degree of flattening is determined while viewing the cornea through a split prism device in the tonometer head. Fluorescein is used to stain the tear film in order to distinguish the cornea from the tear film. The eye is viewed through the cobalt blue filter causing the fluorescein-stained tear film to appear yellow-green. The technique is described below.5 The Goldmann tonometer is not portable. It requires the patient to be cooperative, the patient to sit upright, and a working knowledge of the slit lamp. The Goldmann tonometer in combination with a slit lamp examination provides the clinician with the most detailed information about the patient’s ocular condition. Place two drops of a topical ophthalmic anesthetic agent onto each eye. Place fluorescein dye in the eye. Position the tonometer head and cobalt filter on the slit lamp. Set the tension knob at 10 mmHg. It is more accurate to measure IOP by increasing rather than decreasing the force of applanation. Seat the patient in front of the slit lamp. Support the patient’s chin in the chin rest and place their forehead firmly against the strap (Figure 156-7).
FIGURE 156-7. A patient positioned in the slit lamp with a Goldmann tonometer in position to be advanced onto the cornea.
CHAPTER 156: Intraocular Pressure Measurement (Tonometry)
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FIGURE 156-8. Semicircles as seen through the Goldmann tonometer. A. The inner edges of the semicircles are touching signifying the correct IOP reading. B. Semicircles are not touching because the pressure reading on the tension knob is too low. C. Semicircles are overlapping because the pressure reading is too high.
Instruct the patient to look straight ahead and open both eyes as wide as possible. Spread their eyelids with a thumb and forefinger if necessary. Do not put pressure on the globe while holding the eyelids open. Move the tonometer head within one-half inch of the cornea. Use the control stick on the slit lamp to center the applanation head directly over the pupil. Look for two semicircles on the ocular surface as the tonometer head is advanced onto the corneal tear film (Figure 156-8). Ensure that the tension knob is set at 10 mmHg. The semicircles will not be touching if the patient’s pressure is above 10 mmHg (Figure 156-8B). Turn the tension knob clockwise to raise the reading and counterclockwise to lower the reading. Turn the tension knob up until the inside borders of the fluorescein rings are touching (Figure 156-8A). Read the IOP on the tension knob. The semicircles will overlap if the pressure is below 10 mmHg (Figure 156-8C). Turn the tension knob down until the inside borders of the fluorescein rings are touching (Figure 156-8A). Read the IOP on the tension knob. Clean the tonometer head with an alcohol swab immediately after use. Let it air dry 1 to 2 minutes so that the alcohol evaporates and is not transferred to the corneal surface. Repeat the procedure on the contralateral eye.
HANDHELD TONOMETRY The Tono-Pen XL and the Tono-Pen Avia (Figure 156-9) are lightweight, simple to operate, and can record IOP with the patient in any position. The small contact area is useful in patients with eyelid swelling and corneal surface irregularities. The Tono-Pen calculates IOP using a strain gauge that creates an electronic signal as the 1.5 mm footplate flattens the cornea.10 A single microprocessor chip analyzes each application of the footplate and averages 4 to 10 valid measurements to form one reading. The instrument should be stored in its case when not in use. An Ocu-Film cover should remain over the tip when it is stored and changed with each new patient (Figure 156-9). The Ocu-Film covers are made of latex. Ask the patient about latex allergies prior to using this device. The tip of the Tono-Pen is very sensitive, is easily damaged, and should never be touched. The Tono-Pen XL unit is internally calibrated, thus the instrument calibration should be checked before the first use each day or in the event of unanticipated readings. Calibration should also be performed whenever it is indicated by the LCD display, when batteries are replaced, or after unsuccessful calibration. If the word “bAd” appears in the LCD window, it needs to be calibrated. The Tono-Pen is not used or calibrated daily in the Emergency Department. Thus, it is necessary to check the calibration prior to each use. The display of “Good” in the LCD window indicates that the Tono-Pen is functioning properly. Press the operation button once. The Tono-Pen will display [8.8.8.8] in the LCD window,
FIGURE 156-9. The Reichert Tono-Pen XL and Reichert Tono-Pen Avia. The Tonopen XL has an Ocu-Film cover in place.
followed by a single row of dashes [----], and then a double row of dashes [= = = =]. This indicates that the Tono-Pen is ready to measure IOP. To calibrate the Tono-Pen aim the transducer end straight down. Depress the operation button twice within 1.5 seconds. The TonoPen will beep and display “CAL” in the LCD window. Wait for the Tono-Pen to beep and display “UP” in the LCD window. This can take as long as 15 seconds. Immediately and quickly invert the Tono-Pen so that the transducer end is pointing straight up. The Tono-Pen will beep and display “Good” in the LCD window if it is functioning properly. Repeat the calibration procedure if “bAd” is displayed in the LCD window. Place the patient in a seated or supine position. Instruct the patient to look straight ahead. Place two drops of a topical ophthalmic anesthetic agent onto each eye. Fluorescein is not necessary when using the Tono-Pen. Grasp the Tono-Pen like a pencil and hold it perpendicular to the corneal surface (Figure 156-10). Gently contact the cornea directly over the pupil or central cornea (Figure 156-10). Make contact with the cornea in a series of light taps. The Tono-Pen should not indent the cornea if used properly, reducing the risk if there is an unidentified ruptured globe or a hyphema. The Tono-Pen chirps each time a valid IOP measurement is obtained. The microprocessor sounds a final beep after it receives four valid readings. The mean IOP will be displayed in the LCD window. A single row of dashes [----] indicates that an insufficient number of valid readings were collected. Obtain additional measurements after pressing the operation button.
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pressing on the underlying globe. Measurement during eye movements, blinking, or eyelid movements will elevate IOP. Maneuvers that increase intracranial pressure (e.g., valsalva or breath holding) also increase IOP. Corneal abrasions can occur while using contact tonometers. It is very important to have a cohesive tear film to avoid cornea abrasions. Instruct the patient to blink several times just prior to tonometry to spread the tear film. Apply artificial tears in patients with extremely dry eyes. The Schiøtz tonometer puts significant weight on the cornea and must be applied very gently. Warn the patient that their eye may be uncomfortable when the anesthetic wears off if a small abrasion is suspected after measuring the IOP. Instruct the patient to instill artificial tears every 4 to 6 hours. Treat larger abrasions with a topical ocular antibiotic of choice and schedule a follow-up visit. FIGURE 156-10. The Tono-Pen positioned in front of the cornea.
ALTERNATIVE DEVICES There are many additional handheld tonometers of varying cost, ease of use, and availability. The Perkins MK-2 (Haag-Streit, Essex, UK) and the Kowa HA-2 (Kowa Optimed, Inc., Torrance, CA) are two handheld tonometers utilizing the Goldmann prism technique (i.e., aligning the semicircular images). They are portable, but require a familiarity with Goldmann applanation. The Accupen (Accutome, Malvern, PA) is similar to the Tono-Pen with a few differences. These include ease of use, longer battery life, and not requiring calibration before every use. The Diaton transpalpebral handheld tonometer (Bicom Inc., Long Beach, NY) is designed to measure IOP through a patient’s closed eyelids.11 The Pulsair IntelliPuff (Keeler, Brownhill, PA) is the only portable, handheld, noncontact tonometer. The iCare Rebound (Tiolat Oy, Helsinki, Finland) uses a smaller zone to indent the cornea and claims not to require topical anesthesia.12 This would be particularly useful for the Emergency Department should it prove to be reliable.
SUMMARY The practice of tonometry is essential in guiding appropriate eye care. The Goldmann, Tono-Pen, or Schiøtz contact tonometers are readily available in most Emergency Departments. The literature frequently debates the comparative accuracy of each instrument. The Goldmann applanation tonometer is generally considered the clinical standard.11,12 However, all three instruments are useful for screening IOP in the Emergency Department. Factors such as the patient’s ability to ambulate and the presence of periorbital swelling will influence the choice of an instrument. The Emergency Physician should select a tonometer that feels comfortable and use it routinely. The Emergency Physician will be able to measure IOP rapidly and reliably with repeated use of the tonometer.
157
Digital Globe Massage Carlos J. Roldan and Eric F. Reichman
ASSESSMENT
INTRODUCTION
The normal range for IOP is 10 to 22 mmHg. A baseline IOP is specific to each patient and the patient’s contralateral eye can serve as a control. We can make general assumptions about certain ranges of IOP in order to make rapid clinical assessments and facilitate patient care. Readings of 0 to 9 mmHg should be discussed with an Ophthalmologist, especially if there is a history of recent eye surgery or recent eye trauma. Readings of 10 to 21 mmHg are normal. Readings of 22 to 25 mmHg should be followed up with an Ophthalmologist within 2 to 3 days. IOP readings greater than 26 mmHg require an emergent consultation with an Ophthalmologist.
Digital globe massage has been considered a heroic measure to salvage vision in cases of central retinal artery occlusion (CRAO), an ophthalmologic emergency.1–8 CRAO is one of several diagnoses to consider in the patient with acute painless loss of vision or a visual field. The typical patient is older, between the ages of 50 and 80 years of age, and with significant systemic illnesses. The CRAO is most likely an embolic event secondary to atherosclerotic disease. The vision loss is sudden, monocular, and painless. The outcome for CRAO is poor if treatment is delayed more than 2 hours. Spontaneous remission and recovery of visual function is rare. This condition requires an emergent consultation with an Ophthalmologist for medical management and the consideration of an anterior chamber paracentesis (Chapter 158). Digital globe massage can be used in an attempt to relieve the obstruction or break up the embolus so it moves distally to restore some blood flow to the retina.
COMPLICATIONS Infectious agents can be transferred via tonometer heads.9 It is essential to properly clean each instrument before use, before using it on the contralateral eye, and after use. The use of a 70% isopropyl alcohol swab is an effective disinfectant for the Goldmann and the Schiøtz tonometers. The Tono-Pen has single-use disposable latex covers. Incorrect IOP measurements can occur for a variety of reasons. An improperly working plunger on the Schiøtz tonometer can result in falsely low measurements. IOP will be elevated if measured while the examiner’s hand is holding the eyelids open and inadvertently
ANATOMY AND PATHOPHYSIOLOGY The ophthalmic artery is a branch of the carotid artery (Figure 157-1). The first branch of the ophthalmic artery is the central retinal artery. This vessel runs along the optic nerve and enters the optic nerve. The central retinal artery is the main blood supply to the retina. The macula has an independent blood supply from
CHAPTER 157: Digital Globe Massage
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Cornea
Pupil
Iris
Canal of Schlemm Conjunctiva
Anterior chamber angle Episcleral veins
Ciliary body
Posterior chamber
Pars plicata Pars plana
Lens
Zonule Lens capsule Medial rectus muscle Ora serrata
Lateral rectus muscle
Retina
Choroid
Choroid Retina
Sclera
Sclera
Vitreous Retinal pigment epithelium
Vortex vein
Retinal arterioles and veins Lamina cribrosa
Macula
Arachnoid Optic nerve
Long posterior ciliary artery and long ciliary nerve Pia Optic disk Dura
Central retinal artery and vein
FIGURE 157-1. The anatomy of the eye. (Used with permission from: Riordan-Eva P, Whitcher JP (eds): Vaughan & Asbury’s General Ophthalmology, 17th ed. New York: McGraw-Hill, 2008.)
other branches of the ophthalmic artery. An area between the macula and the optic nerve receives collateral circulation from the central retinal artery and the ciliary arteries in a small percentage of the population. This explains why a patient with a complete CRAO may have a normal appearing macula and occasionally an area of perfusing retina adjacent to the optic nerve area. The individual etiology remains unclear in many cases. The main cause of retinal arterial occlusions is an embolic event lodging in the central retinal artery where it narrows to pass through the lamina cribrosa, or in a smaller distal branch arteriole. The embolism may be comprised of aggregated fibrin and platelets arising from an ulcerated vessel wall thrombus, cholesterol from an ulcerated carotid artery plaque, material from cardiac valvular disease, or thrombus formation from giant cell arteritis. The embolus may also result from an invasive procedure such as cardiac angioplasty, carotid angioplasty and stenting, or a carotid endarterectomy. Abnormal cardiac rhythms are considered an etiology for intracardiac blood clot formation. These may embolize and lodge in the ophthalmic artery or distally in one of the branch arteries. Retrobulbar masses (e.g., a hematoma, neoplasm, or retrobulbar injection) may also lead to an optic nerve and central retinal artery compression.1
PHYSICAL EXAMINATION FINDINGS The patient may display vision compromise ranging from a small visual defect to a decreased ability to finger count or perceive light, and to complete blindness. Grossly, the eye appears normal.
However, an afferent pupillary defect may be evident with little or no reaction to direct light and a normal reaction to consensual light. The initial fundoscopic examination may show a near-normal retinal appearance (Figure 157-2A). This soon progresses to a pale retina, bloodless or attenuated arterioles, and “boxcar” segmentation of the retinal veins (Figure 157-2B). The fundoscopic exam will then reveal a milky and edematous retina with a cherry-red macula if the entire central retinal artery is occluded. If the cilioretinal artery flow is not occluded, there will be an area of perfusion between the optic disc and the macula (Figure 157-2B). An embolus may be visible in the vasculature of the optic disc in rare cases. If a branch retinal artery is occluded, an embolus may be visible in the vessel with ischemia and infarction distal to the occlusion. It has been shown experimentally that the retinal damage is irreversible after 100 minutes of nonperfusion.3 There is anecdotal evidence that heroic measures to salvage vision after a CRAO have sporadically resulted in the return of vision. A large study showed that the average final visual acuity in patients with a CRAO treated with heroic measures compared to those untreated was only a one-quarter line improvement in Snellen chart visual acuity. If the underlying cause of the CRAO is giant cell arteritis, up to 10% of the cases progress rapidly to bilateral vision loss if the arteritis is left untreated.
MEDICAL MANAGEMENT Various methods have been employed to reduce intraocular pressure or to dilate the artery in an attempt to facilitate dislodgement
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the patient if they present to the Emergency Department within 24 hours of symptom onset.7 It should be performed ideally within 90 minutes of the CRAO.
CONTRAINDICATIONS Digital globe massage is contraindicated if the patient has had ocular surgery. Consult an Ophthalmologist in these cases before performing the procedure. Digital globe massage is contraindicated if there is the possibility of a perforated globe. There are otherwise no contraindications to digital globe massage in a nontraumatic CRAO.
EQUIPMENT
A
No special equipment is required to perform a digital globe massage.
PATIENT PREPARATION Perform a fundoscopic examination and visual acuity testing. Document these results in the medical record. Explain the procedure, its risks, and benefits to the patient and/or their representative. This potentially vision-saving procedure should not be delayed. Verbal consent is adequate and the conversation documented in the medical record. Place the patient supine or in a reclining position.
TECHNIQUE
B FIGURE 157-2. Fundoscopic images of the eye. A. Normal examination. B. CRAO with cilioretinal vessel sparing. (Used with permission from: Knoop KJ, Stack LB, Storrow AB, et al: The Atlas of Emergency Medicine, 3rd ed. New York: McGraw-Hill, 2010.)
of the embolus.1–8 None of these have been proven to be of benefit in the management of a CRAO.6 On the other hand, none of these have been proven to be harmful. Thus, they may prove to be useful in saving the patients vision. The following interventions should be considered as coadjuvants to digital globe masses. Oral nitrates (0.5 or 0.4 mg nitroglycerin pills or spray) may vasodilate the retinal artery. Instruct the patient to breathe into a paper bag to increase blood carbon dioxide levels and induce vasodilation. If available, administer carbogen (95% oxygen and 5% carbon dioxide) by face mask instead of using the paper bag. Oral and intravenous carbonic anhydrase inhibitors (500 mg Diamox or acetazolamide) will reduce intraocular pressure and decrease ophthalmic arterial vascular resistance to forward flow. Intravenous mannitol (1 g/kg of a 20% solution) may cause intraocular fluid to exit the eye and decrease intraocular pressure. Hyperbaric oxygenation treatment can compensate to prevent retinal hypoxemia and ischemia in some cases while awaiting the restoration of arterial flow.3 Intra-arterial fibrinolysis with urokinase or recombinant tissue plasminogen activator (rTPA) can be successful in improving vision and shows promise.1,5
INDICATIONS Digital globe massage can be performed in cases of CRAO where medical management is contraindicated or not successful. It can also be performed simultaneously with medical management. Treat
Stand next to the patient’s torso and facing them. Instruct the patient to tightly close the eyelids of the affected eye. Place the dominant thumb over the patient’s eyelids. Apply firm and steady pressure with the thumb for approximately 5 seconds. Abruptly release pressure by quickly lifting the thumb of the eyelids. Repeat the procedure several more times.2
ASSESSMENT Immediately perform a repeat fundoscopic examination and visual acuity testing. Document and compare these to the preprocedural evaluations. It should be noted that the fundoscopic examination may show improvement while the visual acuity has changed very little or not at all. Depending on the ischemic time, visual acuity may never improve. Repeat the digital globe massage if there is little or no improvement in the fundoscopic examination. If significant improvement is noted, the procedure may be repeated in the hope of further improvement.
AFTERCARE All patients must be evaluated by an Ophthalmologist in the Emergency Department. If one is not available, consider transferring the patient to another facility to be evaluated by an Ophthalmologist. These patients require inpatient admission for further evaluation and management. Patients with a CRAO usually have significant comorbidities such as hypertension, atherosclerosis, or diabetes. These patients are at risk for additional morbidity and require prompt medical referral to determine the etiology of the CRAO. Medical testing should include blood pressure evaluation, electrocardiography, echocardiography, blood glucose management, lipid and cholesterol testing, and hyperviscosity studies. Any irregularities or abnormal studies will require further evaluation. Patients over the age of 60 need an immediate erythrocyte sedimentation rate (ESR) test in consideration of the possibility of giant cell arteritis.
CHAPTER 158: Anterior Chamber Paracentesis
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If properly performed, digital globe massage has few immediate complications. Over vigorous digital globe massage can result in a lens dislocation or a ruptured globe.4 Mechanical trauma can result in injury to the cornea, retinal detachments, and intraocular hemorrhage (e.g., hyphema and intravitreal hemorrhage).
may benefit from an anterior chamber paracentesis in combination with digital ocular massage (Chapter 157) and medical management.4 Decreasing intraocular pressure increases retinal perfusion in an attempt to propagate the embolus distally and minimize the amount of visual loss. Traumatic retrobulbar hemorrhages and other extraocular causes of elevated intraocular pressure do not benefit from an anterior chamber paracentesis.
SUMMARY
INDICATIONS
A central retinal artery occlusion is a true ophthalmologic emergency. The patient will present with sudden, painless, and unilateral loss of vision. Immediate management is required in an attempt to restore the patient’s vision. This includes medical management, anterior chamber paracentesis, and digital globe massage. These techniques attempt to reduce intraocular pressure or break up the embolus in order to allow the embolus to move downstream and restore at least partial blood flow to the retina. Despite these interventions, the patient’s vision may not recover.
An anterior chamber paracentesis will immediately reduce intraocular pressure but is not a treatment that resolves the underlying cause of the elevated intraocular pressure. Medical management is usually initiated first to lower intraocular pressure before attempting an anterior chamber paracentesis. An anterior chamber paracentesis is indicated whenever elevated intraocular pressure threatens visual loss and medical management is not successful in lowering intraocular pressure. Reducing the intraocular pressure acutely with an anterior chamber paracentesis in disease states such as acute angle closure glaucoma, uveitis, hyphema, central retinal artery occlusion, and suppurative endophthalmitis will help prevent further irreversible vision loss, especially if used in conjunction with other medical modalities.5–7 There are numerous nonemergent indications for an Ophthalmologist to perform an anterior chamber paracentesis. Diagnostically, an anterior chamber paracentesis can be used for aqueous humor sampling for a suspected infection, lymphoma, and intravitreal drug level monitoring.8,9 It is also performed for isotonic saline injection for flattened anterior chamber reformation and numerous ophthalmologic surgical procedures.
COMPLICATIONS
158
Anterior Chamber Paracentesis Rene Pineda Carizey
INTRODUCTION Anterior chamber paracentesis is the removal of fluid from the anterior chamber, the area just anterior to the iris and lens, and immediately posterior to the cornea. Although not often formally taught nor performed in the Emergency Department, an anterior chamber paracentesis is a fairly quick, simple, and safe procedure with important diagnostic and therapeutic roles.1–20 The long-term prognosis is directly related to the duration of symptoms for disease states that present with increased intraocular pressure, such as acute closure glaucoma and central retinal artery occlusion. In a sense, “Time is Eye.” The Emergency Physician should become familiar with this technique. Its use can potentially prevent irreversible vision loss, especially when medical management is not sufficient in lowering intraocular pressure.
ANATOMY AND PATHOPHYSIOLOGY The eye is a fluid-filled, closed system with a one-way valve. Aqueous humor is produced by the ciliary body and flows from the posterior chamber to the anterior chamber. Once in the anterior chamber, the aqueous humor then travels through a fine trabecular meshwork at the anterior chamber angle (the one-way valve) and leaves via the canal of Schlemm. Intraocular pressure normally measures between 10 and 22 mmHg. This represents the balance between the production and outflow of aqueous humor.3 Tonometry is used to measure intraocular pressure (Chapter 156). An increase in aqueous humor production, resistance to the outflow of aqueous humor, or additional fluid (e.g., pus or blood) in the vitreous body can severely increase intraocular pressure, potentially causing permanent visual loss due to ischemia. In addition to medical therapies, removing fluid via an anterior chamber paracentesis will reduce intraocular pressure to help prevent further ischemia. Central retinal artery occlusion (CRAO), usually from an atherosclerotic embolic event, is another potential cause of visual loss that
CONTRAINDICATIONS There are no absolute contraindications to performing an anterior chamber paracentesis since the patient’s vision is at risk. Consult an Ophthalmologist prior to the procedure if a ruptured globe is suspected. Relative contraindications include uncooperative patients, patients with allergies to topical ocular anesthetics, and if the Emergency Physician is not comfortable performing the procedure. The patient’s airway, breathing, hemodynamic status, and other life-threatening events should always be addressed prior to the procedure.
EQUIPMENT • Sterile povidone iodine solution • Topical ophthalmic anesthetic drops, e.g., 0.5% proparacaine or tetracaine • Broad-spectrum topical antibiotic eye drops, e.g., fluoroquinolone • Sterile saline minim • 15° super sharp micro blade • 1 mL tuberculin syringe • 27 to 30 gauge, 5/8 inch needle1,8,11,12 • Slit lamp
PATIENT PREPARATION Inform the patient of the reasons for performing an anterior chamber paracentesis, including its risks and benefits. Obtain a signed procedural consent and place it in the medical record. Reassure the patient that a “pressure sensation” might be felt during the procedure but they should not experience pain.
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FIGURE 158-1. The hypodermic needle technique. A. The needle is inserted obliquely at the limbus. B. Transverse view of the eye. The needle enters the cornea at the limbus and is directed anteriorly into the anterior chamber.
Remove all contact lenses prior to placing any topical ocular medications or using fluorescein. Perform a visual acuity assessment and an intraocular pressure measurement prior to any intervention to document the patient’s baseline status and for serial comparisons after the procedure. If the patient’s tetanus status is unknown or their last tetanus booster has been greater than 10 years, administer a tetanus booster intramuscularly. Administer antiemetic and pain medication if the patient is symptomatic. Retching and vomiting increases intraocular pressure and complicates the procedure. Instill one to two drops each of the topical ophthalmic anesthetic and the broad-spectrum ophthalmic antibiotic onto the affected eye. Some Ophthalmologists instill two drops of sterile povidone iodine solution onto the cornea followed by topical ophthalmic anesthetic drops to dilute it.17,18,20 Place the patient comfortably in a chair. Position their chin on the slit lamp chin rest. Attempt to comfortably immobilize the patient’s head. Use an assistant if needed. Check for proper anesthesia by softly brushing the cornea with cotton-tipped swab or rechecking intraocular pressure.
TECHNIQUES Numerous techniques have been described to perform an anterior chamber paracentesis. The quickest, simplest, and easiest to perform are the hypodermic needle and saline minim techniques. The surgical technique is often performed by an Ophthalmologist.
HYPODERMIC NEEDLE TECHNIQUE Anesthetize the cornea and position the patient in the slit lamp as described above. Arm a tuberculin syringe with a 27 to 30 gauge needle. Slightly withdraw the plunger to break the bead on the syringe. Position the tip of the needle at the limbus, somewhere between the 4 o’clock and 8 o’clock position (Figure 158-1A). Gently insert the needle through the cornea and angled anteriorly. This will ensure that the tip of the needle will enter the anterior chamber and not injure the ciliary body, iris, or lens (Figure 158-1B). The anterior chamber holds approximately 0.3 mL of fluid. Slowly withdraw the plunger and aspirate 0.1 mL of fluid from the anterior chamber. Withdraw the needle. Apply topical ophthalmic antibiotic drops immediately after the procedure.
Anesthetize the cornea and position the patient in the slit lamp as described above. Prepare the minim. Twist off and discard the tip of the minim. Firmly apply a 27 to 30 gauge needle to the open end of the minim. Grasp the needle-minim unit with the thumb and index finger of the dominant hand. Gently squeeze the minim until one drop of sterile saline is expressed from the tip of the needle. Do not release pressure on the sides of the minim. Position the tip of the needle at the limbus, somewhere between the 4 o’clock and 8 o’clock position (Figure 158-2). Gently insert the needle through the cornea and angled anteriorly. This will ensure that the tip of the needle will enter the anterior chamber and not injure the ciliary body, iris, or lens. Slowly open the thumb and index finger to release the compression on the minim. The aqueous humor will flow from the anterior chamber into the minim. Do not withdraw enough fluid to dimple the cornea. Withdraw the minim until the needle exits the eye. Apply topical ophthalmic antibiotic drops immediately after the procedure.
SURGICAL TECHNIQUE Anesthetize the cornea and position the patient in the slit lamp as described above. Position the tip of the 15° super sharp micro blade at the limbus, somewhere between the 4 o’clock and 8 o’clock position. Gently insert the blade through the cornea and angled anteriorly. This will ensure that the tip of the blade will enter the anterior chamber and not injure the ciliary body, iris, or lens. Withdraw the blade. Carefully and gently insert a 27 to 30 gauge needle on a tuberculin syringe through the incision. Aspirate 0.1 mL of fluid from the anterior chamber and withdraw the needle. As an
SALINE MINIM TECHNIQUE A saline minim attached to a hypodermic needle is an alternative to using a syringe (Figure 158-2). This technique is simpler to perform when compared to using a hypodermic needle.11,12,15 A saline minim is a single use, soft sided, disposable container containing 0.5 mL of sterile saline.
FIGURE 158-2. The saline minim technique.
CHAPTER 159: Corneal Foreign Body Removal
alternative, a 27 to 30 gauge needle on a saline minim can be used. Apply topical ophthalmic antibiotic drops immediately after the procedure.
ASSESSMENT After the procedure, immediately perform an intraocular pressure measurement with the same device used before the procedure to measure intraocular pressure. The intraocular pressure and symptomatic complaints should significantly decrease after the anterior chamber paracentesis procedure. Perform serial intraocular pressure measurements in 30-minute intervals for 2 hours to assess for any recurrence of elevated intraocular pressure. Perform and document a postprocedure visual acuity. Readdress any symptomatic complaints of eye pain, nausea, and headache. Significant decreases in intraocular pressure have been shown immediately, 2 hours, 2 days, and up to 2 weeks after an anterior chamber paracentesis with near resolution of symptoms.5,6,19
AFTERCARE An Ophthalmologist should evaluate the patient in the Emergency Department. Immediate surgical intervention may be indicated if there is no improvement in the patient’s symptoms or the intraocular pressure is persistently elevated despite medical management and an anterior chamber paracentesis. Patients can usually be safely discharged home once symptoms resolve and the intraocular pressure has normalized. Arrange close follow-up with an Ophthalmologist within the next 24 to 48 hours. Patients are typically discharged with broad-spectrum topical ophthalmic antibiotics, oral pain medications, oral antiemetics, and other antiglaucoma medications including oral acetazolamide, topical ophthalmic beta blockers, ophthalmic pilocarpine, and/or ophthalmic steroids.10,15 The consulting Ophthalmologist will determine the proper medical management including the medications, their strength, and the frequency of administration. The patient should immediately return to the Emergency Department if they develop increased eye pain, severe nausea and/or vomiting, or any visual disturbances (e.g., decreased vision, photophobia, and halos around lights).
COMPLICATIONS Mechanical injury to ocular structures (e.g., ciliary body, corneal abrasions, iris, or lens), infection, and bleeding comprise the most serious complications after an anterior chamber paracentesis.13,14 Inadvertent injection of air into the anterior chamber occurs, but is typically a small amount and resolves spontaneously.12 Allergic reactions to any of the medications used can also occur.
SUMMARY Many types of disease pathologies can acutely elevate intraocular pressure and result in potential irreversible vision loss. Immediate reduction of the intraocular pressure by using medical treatments in conjunction with an anterior chamber paracentesis will reduce the amount of ischemic time, thereby reducing the amount of possible permanent visual impairment. Multiple studies have repeatedly demonstrated the efficacy and safety of an anterior chamber paracentesis when used acutely to reduce intraocular pressure.11,12 Although performing an anterior chamber paracentesis is often met with apprehension by the Emergency Physician, it is a procedure routinely performed in the office setting. Emergency Physicians should become familiar with an anterior chamber paracentesis because it is safe, simple, effective, relatively quick, and also has the potential to save a patient’s vision.
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Corneal Foreign Body Removal Eric F. Reichman
INTRODUCTION Corneal foreign bodies are a common complaint confronting Emergency Physicians and account for approximately 35% of all eye injuries seen.1 Many objects have been implicated as a source of corneal foreign bodies including, but not limited to glass, metal, wood, dirt, dust, insects, and plant particles.1 The majority of ocular foreign bodies require prompt removal. More than 75% of retained foreign bodies present on the eye surface are corneal in nature, and if left in place for more than 3 days will result in a keratitis.2 The prevailing symptom that forces patients to seek treatment is the sensation of an ocular foreign body or simply the pain associated with the foreign body. A variety of techniques exist for removal of ocular foreign bodies. A discussion of each of these techniques is necessary to determine the proper technique for a given situation.
ANATOMY AND PATHOPHYSIOLOGY Many foreign bodies are diverted from the surface of the eye by the rapid blinking action of the eyelids and the eyelashes. A foreign body may not necessarily lodge itself into the cornea or the surrounding scleral surface if it is able to get past the eyelids and eyelashes. It may be washed to the inner canthus by a combination of blinking and tear flow. The foreign body may occasionally be carried away via drainage through the lacrimal ducts.2 Objects that resist these means of diversion may be found in the upper or lower fornices, the channels created by the fold of the inner surfaces of the eyelids in communication with the conjunctival surface of the eye. The foreign body in the upper fornix is typically found lodged in the subtarsal groove on the inner surface of the upper eyelid, inferior to the tarsal plate.2 Foreign bodies may also travel deeper into the respected fornices where they may be difficult to find. Foreign bodies may lodge themselves into the surface of the conjunctiva overlying the sclera or into the cornea itself, which obviously carries the most risk of serious injury or permanent scarring. The cornea is 40 mmHg), an afferent papillary defect, chemosis, mydriasis, diminished retropulsion of the affected globe to direct manual pressure, ophthalmoplegia, and fundoscopic signs of retinal ischemia (rare).1–28 Orbital compartment syndromes have been described in multiple clinical settings. The presentation that Emergency Physicians will most likely encounter is an acute posttraumatic retrobulbar hemorrhage leading to an orbital compartment syndrome, with subsequent rapid loss of vision.1,2 Orbital compartment syndromes have been documented following blepharoplasty, retrobulbar anesthesia, orbital and sinus surgery, orbital fractures with intraorbital emphysema, spontaneous subperiosteal hemorrhages, and spontaneous retrobulbar hemorrhages.3–9 Orbital compartment syndromes may also occur as the result of chronic and progressive disease processes (e.g., neoplasms, infections, and inflammations).10 Acute orbital compartment syndromes demand prompt recognition because irreversible loss of vision and even permanent blindness occurs without rapid treatment.11 Once the diagnosis of an acute orbital compartment syndrome is made, emergent surgical intervention is indicated. An immediate lateral canthotomy and cantholysis are indicated within 1 hour of injury and ocular dysfunction. Medical interventions aimed at reducing intraocular pressure (e.g., mannitol, acetazolamide, topical beta-blockers, etc.) should be considered adjunctive therapy and not a substitute for surgical intervention.
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is formed by the maxillary bone. The globe is enclosed in a fascial envelope within the bony orbit. The medial and lateral canthal tendons provide structural fixation of the eyelids to the orbital rim. The lateral canthal tendon (LCT) is located posterior and inferior to the lateral canthal fold (Figure 162-1). The LCT originates from the superior and inferior lateral tarsal plates (Figure 162-1) and attaches to the lateral orbital tubercle of the zygoma (Figures 162-1 & 162-2). The LCT consists of a superior crus from the superior tarsal plate and a inferior crus from the inferior tarsal plate. The LCT measures 10.6 mm (SD ± 0.9 mm) in length from its attachment site to the lateral canthal angle. It is 10.2 mm (SD ± 0.8 mm) in width at its origin at the lateral ends of the tarsal plates. It attaches 1.5 mm (SD ± 0.3 mm) behind the orbital margin and approximately 9.7 mm (SD ± 0.8 mm) below the frontozygomatic suture at the lateral orbital tubercle.12 Immediately anterior to the LCT is Eisler’s pocket, a collection of adipose tissue. Posterior to the LCT, at its attachment site to the lateral orbital tubercle is the check ligament of the lateral rectus muscle (Figure 162-2). Any increase in intraorbital contents (e.g., retrobulbar hematoma, intraorbital emphysema, and retrobulbar abscess) will result in an elevation of intraorbital pressure because the orbit is a closed space. The globe itself may partially accommodate some of the elevation in intraorbital pressure by prolapsing forward (Figure 162-3). This will result in ocular pain and proptosis. The intraorbital pressure rises dramatically as the orbit approaches maximal distention. This rise in intraorbital pressure leads to a chemosis, elevated intraocular pressures, and compression of the intraorbital cranial nerves. If the compression is severe enough, the patient develops an ophthalmoplegia and an afferent papillary defect. The exact mechanisms by which orbital compartment syndromes result in blindness remain speculative.13–24 A common theory is that as the intraorbital pressure increases, orbital venous outflow is impeded and leads to diminished retinal and optic nerve arterial perfusion pressures. This results in an afferent pupillary defect, diminished visual acuity, and, rarely, fundoscopic signs of retinal ischemia. Over time, the elevated intraorbital pressure leads to irreversible optic nerve and/or retinal ischemia. Experimental studies have demonstrated that irreversible ischemic injury to the retina may occur within 90 minutes of vascular insufficiency.18–21 Additional theories suggest that direct mechanical compression or
Lateral canthal tendon
Levator aponeurosis
B A
C
Tarsal plates
ANATOMY AND PATHOPHYSIOLOGY The orbit of the eye is a closed space posterior to the orbital septum and contained within the bony orbit. The lateral wall of the orbit is formed by the zygomatic bone. The posterior wall is formed by the sphenoid bone. The medial wall is formed by the ethmoid bone. The roof is formed by the frontal bone. The floor
FIGURE 162-1. The lateral canthal tendon, or LCT (A = the vertical height of the LCT, B = the distance from the frontozygomatic suture to the midpoint of the LCT origin, and C = the length of the LCT as measured from the canthal margin to its origin).
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Orbicularis oculi muscle Orbital septum Eisler's pocket Lateral canthal tendon Lateral orbital tubercle Check ligament
FIGURE 162-2. An axial view of the orbital contents. Identification of the LCT will require dissection of the conjunctiva and fascial tissues with a hemostat and iris scissors. A pocket of adipose tissue (Eisler’s pocket) will be encountered beneath the superficial tissue layers. The LCT lies just posterior to this adipose tissue collection.
longitudinal traction on the optic nerve may contribute to the loss of vision in orbital compartment syndromes.22,24 Elevated intraorbital pressure may also occur from large volume fluid resuscitation in patients without ocular trauma.29 A history of progressive loss of vision following orbital trauma suggests a reversible disease process (e.g., retrobulbar hemorrhage). If loss of vision is immediate and complete following orbital trauma, the chance of recovery of vision is poor.25 This is because the loss of vision in the latter case is due to direct optic nerve, retinal, or vascular injury rather than an orbital compartment syndrome.
CONTRAINDICATIONS There are no definite contraindications to performing this procedure, as permanent loss of vision may result from untreated acute orbital compartment syndromes. The patient’s airway, breathing, circulation, and any life-threatening injuries must be addressed prior to performing this procedure. If the patient is very young, confused, or uncooperative, sedation and restraint or procedural sedation (Chapter 129) will be required to prevent iatrogenic injury to the globe.
INDICATIONS
EQUIPMENT
An acute orbital compartment syndrome is an indication for immediate orbital decompression.23 Multiple case series have documented the efficacy of immediate orbital decompression in restoring visual acuity to affected patients.24–28
• Povidone iodine or chlorhexidine solution • Topical ocular anesthetic solution, proparacaine or tetracaine • Lidocaine 2% with epinephrine
Periorbita
Levator palpebrae muscle Superior rectus muscle Orbital fat
Optic nerve Dura
Tarsus Septum FIGURE 162-3. A sagittal view of the orbital contents. Note the location of the retrobulbar hemorrhage.
Retrobulbar hemorrhage Inferior rectus muscle Inferior oblique muscle
CHAPTER 162: Lateral Canthotomy and Cantholysis or Acute Orbital Compartment Syndrome Management
• • • • • • • •
30 gauge 0.5 inch needle on a 3 cc Luer Lock syringe Ocular tonometer (applanation, Schiøtz, or Tono-Pen) Sterile saline or sterile water Straight mosquito hemostat Iris scissors Tissue forceps 2 × 2 gauze squares Topical ocular antibiotic ointment (e.g., bacitracin, ciprofloxacin, erythromycin, gentamicin, neosporin, polysporin, or sulfacetamide) • #10 disposable scalpel (optional) • Disposable hot tip cautery pen (optional)
PATIENT PREPARATION Explain the procedure to the patient and/or their representative, including the risks, benefits, and outcome if it is not performed. This is a painful procedure for the awake and alert patient, so lucid patients will require parenteral medications for analgesia and sedation in addition to local anesthetics. Consider the use of procedural sedation (Chapter 129) if not contraindicated. Measure and record the visual acuity. Perform a brief ophthalmologic examination. Apply topical ocular anesthetic solution to the conjunctiva of the affected eye. Measure and record the intraocular pressure.
TECHNIQUE Place the patient supine. Clean the eyelids and surrounding skin of any blood, dirt, and debris. Apply povidone iodine or chlorhexidine solution to the eyelids and allow it to dry. Do not let these solutions drip into the eye. Irrigate the lateral canthal fold region with sterile saline or sterile water. Using aseptic technique, identify the lateral canthal fold (Figure 162-4). Inject 1 mL of local anesthetic solution with epinephrine subcutaneously using a 30 gauge, 0.5 inch needle on a 3 mL syringe along the lateral canthal fold. The goal is to anesthetize the tissue extending laterally from the canthal fold to the orbital rim. Caution must be exercised to avoid inadvertent needle puncture of the globe. Insert a straight mosquito hemostat at the lateral canthal fold. Place one jaw of the hemostat anterior and one jaw posterior to the
FIGURE 162-4. Illustration of lateral canthotomy. Iris scissors are used to cut all tissue layers along the lateral canthal fold up to the orbital rim.
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lateral canthal fold. Advance the tips of the hemostat laterally until the orbital rim is encountered. Clamp and compress the intervening tissue for approximately 1 minute. This will minimize any bleeding precipitated by the lateral canthotomy. Remove the hemostat. Cut all the tissue layers along the lateral canthal fold up to the orbital rim (lateral canthotomy) with an iris scissors (Figure 162-4). All tissue layers, from the skin to conjunctiva, must be incised down to the orbital rim. Use a #10 scalpel blade to cut the tissues in cases of severe distortion of the anatomy due to edema or if iris scissors are not readily available. A disposable hot cautery pen, if available, can be used to achieve hemostasis. Gently grasp the lower eyelid with a hemostat or forceps and retract it outward. Identify the LCT located just posterior and inferior to the lateral canthal fold (Figures 162-1 & 162-2). Dissect the conjunctiva and fascial tissues with a hemostat or iris scissors. A pocket of adipose tissue (Eisler’s pocket) will be encountered beneath the superficial fascial planes (Figure 162-2). The LCT lies just posterior to this adipose tissue collection (Figure 162-2). Completely divide the LCT vertically at its midportion with an iris scissors or #10 scalpel (lateral cantholysis) to transect the inferior crus of the tendon.
ASSESSMENT A successful lateral canthotomy and cantholysis will cause an immediate decrease in intraocular pressure to less than 40 mmHg. Recheck the intraocular pressure. If the intraocular pressure remains elevated, reexplore the lateral canthal tendon region to make sure that the inferior crus has been completely transected. If transected, cut the superior crus of the tendon to transect it. Occasionally, the intraorbital and intraocular pressures will remain elevated despite successful cantholysis. These refractory cases necessitate emergent decompression of the deep orbital wall.7 Such decompressions call for operative techniques that are to be performed by Ophthalmologists and Otolaryngologists. The resolution of proptosis, afferent pupillary defects, and restoration of visual acuity will usually not occur immediately. Patients who respond to surgical intervention will gradually regain their visual acuity over a period of hours to days.
AFTERCARE Apply a topical antibiotic ointment along the canthotomy site. In orbital compartment syndromes, elevated intraocular pressures merely reflect elevated intraorbital pressures. Therefore, any attempts to decrease intraocular pressures will not reliably reduce retrobulbar optic nerve compression. Medical interventions decreasing intraocular pressure may be used following, or in conjunction with, a lateral canthotomy and cantholysis. These interventions are similar to those employed for the management of elevated intraocular pressures in patients with acute angle-closure glaucoma. This includes the use of topical beta-blockers, central acting alpha agonists, intravenous mannitol, and carbonic anhydrase inhibitors. These medications are not a substitute for surgical orbital decompression. Many patients with an orbital compartment syndrome have other injuries requiring hospital admission following their Emergency Department evaluation and treatment. Ensure a timely Ophthalmologic consultation for a complete eye exam and possible repair of the canthotomy and cantholysis sites once the orbital compartment syndrome resolves. Repair of the lateral canthal fold and lateral canthal tendon is controversial. Many Ophthalmologists do not advocate suture repair, as a majority of wounds heal without complication by secondary intention. Patients with no other acute medical or surgical conditions,
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restored vision, a normal ophthalmologic examination, and normal postprocedural intraocular pressures may be discharged after evaluation by an Ophthalmologist.
COMPLICATIONS Time constraints, abnormal anatomy (resulting from traumatized tissue), and lack of familiarity with the lateral canthotomy and cantholysis techniques can make this a challenging procedure. Hemorrhage is often minimal and can be controlled with direct pressure. The use of a disposable cautery pen can be helpful. Mechanical injuries can include globe perforation, injury of the lateral rectus muscle, scleral lacerations, and secondary ectropion. Most of these complications can be prevented by knowing and identifying the anatomic landmarks, reviewing the procedure before it is performed, and using extreme care in performing the canthotomy and cantholysis. Despite the use of aseptic technique, infections at the canthotomy and cantholysis sites can occur. They should be treated with parenteral antibiotics that cover typical skin flora.
SUMMARY Emergency Physicians must be able to promptly recognize and be prepared to manage an acute orbital compartment syndrome, defined by an acute elevation of intraorbital and intraocular pressure with resultant ocular dysfunction. Patients will present with ocular pain, proptosis, an afferent pupillary defect, and diminished visual acuity. An acute orbital compartment syndrome requires emergent treatment to preserve vision. An immediate lateral canthotomy and cantholysis are indicated, preferably within 1 hour of injury and ocular dysfunction. Medical management should be considered an adjunctive therapy. Many patients will regain their visual function if the procedure is performed soon after the injury and before permanent ischemic changes occur.
nerve and retinal vasculature are subjected to an abnormal amount of traction, resulting in possible damage to these structures or the retina.1 The end result is partial or full blindness in the affected eye if it is not reduced before irreversible ischemic changes occur.
ANATOMY AND PATHOPHYSIOLOGY There are three major causes of globe luxation: spontaneous, voluntary, and traumatic. Spontaneous luxation tends to occur in individuals with shallow orbits.2 Structural abnormalities—such as laxity of the supporting muscles and fascia as well as anomalous extraocular muscles—can predispose to spontaneous luxation.2–4 Pathologic processes that cause proptosis can predispose to luxation. The literature documents cases of luxation associated with orbital tumors, Graves’ disease, cerebral gummas, histiocytosis X, and craniofacial dysostosis.1,5,6 Voluntary luxation occurs in individuals who learn to cause globe propulsion by using a digit or use of their extraocular muscles. Some patients use a Valsalva maneuver to luxate their globe(s) voluntarily. Traumatic luxation results from trauma to the globe or the surrounding bony orbit. It can occur from motor vehicle accidents or even relatively minor trauma to the face.7,8 Traumatic luxation can also occur from intentional eye gouging or even during the forceps-assisted delivery of a neonate.9,10 The normal anatomic relationship of the globe to the surrounding structures is seen in Figure 163-2. The midcoronal plane of the eye is a transverse section through the eye in the coronal plane. It is through the widest portion of the eye and divides the eye into anterior and posterior halves. When the eyelids get behind the midcoronal plane, the orbicularis oculi muscle is pulled taut and begins to go into spasm. This spasm prevents spontaneous reduction of the globe.
INDICATIONS
163
Globe Luxation Reduction Jeffrey S. Schlab
INTRODUCTION Luxation of the globe is a rare event whereby the eyelids slip behind the midcoronal plane of the eye in an extremely proptosed eyeball (Figure 163-1). The orbicularis oculi muscle then goes into spasm, which maintains the luxation of the globe. Extraocular eye movements become severely limited. The optic
Globe reduction is indicated to relieve traction on the optic nerve and retinal vessels. The patient’s visual acuity has the potential of being compromised without prompt reduction. Sustained globe luxation is physically and psychologically uncomfortable for the patient, may result in permanent loss of vision, and is difficult to reduce without general anesthesia.
CONTRAINDICATIONS Obvious rupture of the globe and extensive orbital fractures that require immediate surgical intervention are relative contraindications to globe reduction. Edema and retrobulbar hemorrhage can make reduction outside the Operating Room impossible.1,6
FIGURE 163-1. The luxated globe. A. Superior view. B. Lateral view.
CHAPTER 163: Globe Luxation Reduction
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Levator palpebrae superiorus muscle Orbicularis oculi muscle
Superior rectus muscle
Superior tarsal muscle Superior fornix Bulbus oculi Midcoronal plane of the eye
Optic nerve
Inferior tarsal muscle
Inferior rectus muscle
Inferior oblique muscle FIGURE 163-2. Anatomy of the eye and orbit.
EQUIPMENT • Topical ocular anesthetic agent (e.g., 0.5% proparacaine or tetracaine) • Sterile gauze and gloves • Sutures or eyelid retractors • Local anesthetic solution (1% lidocaine), if eyelid retaining sutures need to be placed • 3 mL syringe • 27 gauge needle
action of the levator palpebrae superioris muscle and simultaneously relaxes the superior rectus muscle.12 While traction is being applied to the eyelids, apply steady and gentle pressure with a gloved thumb to the exposed superior sclera of the globe in a simultaneously downward and posterior direction. Physical contact over the sclera minimizes discomfort and avoids possible
PATIENT PREPARATION Prior to any attempt at reduction, a directed eye exam addressing the integrity of the globe, visual acuity, pupillary reactivity, and range of ocular motion should be performed. Describe the procedure to the patient and/or their representative. Answer any questions about the procedure and obtain an informed consent for the procedure. Relaxation of the patient and the orbicularis muscles are essential for procedural success. The use of a parenteral anxiolytic and analgesic or procedural sedation (Chapter 129) is recommended if not contraindicated.11 Place the patient supine. Instill a topical ocular anesthetic agent onto the affected eye. Allow 1 to 2 minutes for the anesthetic to take full effect.
TECHNIQUE Reduction of a globe luxation ideally requires two people (Figure 163-3).11,12 Instruct an assistant to apply steady upward and outward traction on the upper eyelid and downward and outward traction on the lower eyelid by grasping and pulling on the eyelashes. Instruct the patient to maintain a constant downward gaze. The downward gaze posture negates the retracting
FIGURE 163-3. Reduction of a globe luxation.
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corneal abrasions.12 Continue to apply constant and gentle pressure until the globe is manipulated back into the orbit.1,6
ALTERNATIVE TECHNIQUE
164
Hordeolum (Stye) Incision and Drainage Sami H. Uwaydat and Jamil D. Bayram
Occasionally the patient’s eyelashes are small or not accessible, or an assistant is not available. In these cases, an eyelid retractor may be placed behind the eyelids to provide countertraction. Other authorities have recommended the placement of a suture through the anesthetized skin of the eyelids to help retract them.1,4,6 Extreme care must be taken to prevent penetration of the globe by the anesthetic needle or the suture needle if retaining stitches are placed in the eyelids. If either of these techniques are used, the globe is then reduced in the same manner as described previously.
A hordeolum is a suppurative infection of one of the eyelid glands. The nomenclature that describes infectious and inflammatory conditions of the eyelid glands is at times confusing. A brief description of the eyelid margin anatomy may help resolve some of the confusion. The patient usually presents with an acutely painful, erythematous, localized, and tender mass on either the upper or lower eyelid. A hordeolum may be associated with a blepharitis.
ASSESSMENT
ANATOMY AND PATHOPHYSIOLOGY
A repeat and complete eye examination must be performed after the procedure and documented in the medical record. Pay special attention to visual acuity, pupillary reflexes, and range of extraocular muscle movement.1,6,10 Full visual acuity may not return to baseline for several days or longer.4 A search for the possible causes of a nontraumatic luxation should be initiated in the Emergency Department.1 This includes but is not limited to thyroid function testing and orbital imaging to rule out a tumor. This evaluation should be performed after consultation with an Ophthalmologist. Conduct a search for associated injuries such as a bony periorbital fracture, globe rupture, retroorbital hematoma, or intracranial injury in the cases of traumatic luxation.
The eyelid is composed of numerous structures (Figure 164-1). The eyelid skin is thin and vascular. The orbicularis oculi muscle encircles the eyelids and controls their movements. The hair follicles which form the eyelashes are fine and delicate in comparison to hair on other body areas. Numerous glands are contained within the eyelids. The glands of Zeis are modified sebaceous glands associated with the hair follicles. The glands of Moll are modified sweat glands that open into the base of the hair follicles. The tarsus is a rigid fibrous plate containing the sebaceous Meibomian glands. The orifice of the elongated Meibomian glands can be seen posterior to the eyelashes at the eyelid margin. The inner aspect of the eyelids is lined by the thin and delicate conjunctiva. A hordeolum can be located internally or externally in relation to the eyelid and tarsal plate. They are essentially an abscess of the eyelid. An internal hordeolum is a bacterial infection of the Meibomian gland and usually points to the inside or conjunctiva (Figure 164-2). An internal hordeolum is usually larger than an external hordeolum. If the infection blocks the neck of the Meibomian gland, the infection points toward the conjunctival surface of the eyelid. If the neck of the Meibomian gland is not blocked, the infection often points to the eyelid margin. An external hordeolum, also known as a stye, is a bacterial infection of the glands of Zeis or Moll. These tend to be small, superficial, and point to the eyelid skin or, more commonly, the eyelid margin. The most common causative agent in both internal and external hordeola is Staphylococcus aureus.1 Patients with a hordeolum almost always present with localized pain, redness, and swelling of the eyelid margin. It is usually a benign process but can progress to a preseptal or septal cellulitis. It may rarely result in a corneal epithelial defect,2 periorbital necrotizing fasciitis,3 and bacteremia.4 A chalazion is a chronic, more than 2 weeks, granulomatous inflammation of a sebaceous Meibomian gland. Acute chalazion lesions, those less than 2 weeks old, are often difficult to distinguish from an acute hordeolum. Clinically, the management of an acute chalazion and an acute hordeolum are the same and it is not necessary to differentiate the two processes. A chalazion may persist for many months and slowly enlarge over time. A chronic chalazion is characterized by a painless localized swelling of the eyelid margin with no inflammatory signs and feels rubbery upon palpation. A chronic chalazion does not require an urgent intervention and should be managed by an Ophthalmologist. A chalazion that is acute, large, or causes local irritation may require an incision and drainage. Recurrent chalazia require an evaluation by an Ophthalmologist to rule out a malignancy.
AFTERCARE Patients with spontaneous luxations that reduce without difficulty and who are without visual impairment may be discharged home after consultation with an Ophthalmologist. These patients require follow-up with the Ophthalmologist within 24 hours.1,6 They should be instructed to avoid Valsalva maneuvers.1 All patients with traumatic luxation require emergent Ophthalmologic consultation and imaging of the orbits.1,6
COMPLICATIONS It is not uncommon for eyelashes to be retained in the conjunctival fornices after this procedure.10 A thorough evaluation and removal of any free eyelashes is warranted to prevent corneal abrasions or injury.1,6,10 If one or two attempts at reduction are not successful, instill saline drops to the eye and apply an eye shield to prevent further injury while an emergent Ophthalmologic consult is obtained.1,6 Refer to Chapter 161 for the complete details regarding the application of an eye shield.
SUMMARY Globe luxation is a rare entity that can be effectively dealt with in the Emergency Department. Prompt intervention by an Emergency Physician can result in the preservation of visual acuity. After a brief initial eye examination, uncomplicated cases can be reduced by the Emergency Physician. Complicating factors—such as the presence of trauma, an open globe injury, or the inability to reduce the globe—warrant emergent Ophthalmologic consultation. Predisposing factors for a spontaneous luxation should be investigated.
INTRODUCTION
CHAPTER 164: Hordeolum (Stye) Incision and Drainage
Levator palpebrae superioris muscle
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Eyebrow hair
Skin
Orbital septum
Superior tarsal muscle (of Müller) Palpebral conjunctiva
Orbicularis oculi muscle Tarsal plate
Palpebral conjunctiva Cornea
Meibomian glands Zeis' glands Eyelashes (cilia) Meibomian orifice
FIGURE 164-1. Eyelid margin anatomy. The type and location of the infected gland determine whether it is an internal hordeolum or an external hordeolum (stye).
MANAGEMENT Hordeola are initially managed conservatively. Warm compresses should be applied over the eyelid for 10 to 15 minutes at a time, and three to six times per day. An alternative and portable solution to warm compresses would be to place 8 to 10 ounces of dry rice in a sock and heat it in a microwave (typically for 30 seconds). The rice tends to maintain the heat for a longer period compared to the warm compresses. Apply diluted baby shampoo to the eyelid margins with a washcloth or cotton-tipped applicator for daily eyelid scrubs. Topical antibiotic ointments
(e.g., erythromycin) can be placed in the conjunctiva or on the eyelid margin three times per day. The purpose of topical antibiotics is to prevent the infection spreading to adjacent hair follicles. Oral antibiotics are indicated only if the signs and symptoms of a cellulitis develop. Most hordeola will spontaneously drain and resolve within 5 to 7 days with conservative management. Treat any accompanying blepharitis to prevent the formation of additional hordeola.
INDICATION Surgical excision is warranted if the hordeolum does not resolve with conservative management and the patient has significant discomfort. A hordeolum can be excised if it causes a cosmetic deformity, blocks the visual axis, or is of a significant size.
CONTRAINDICATIONS
FIGURE 164-2. An internal hordeolum with redness and swelling.
Not all hordeola should be incised and drained in the Emergency Department. Hordeola close to the lacrimal puncti or the medial canthus are best managed conservatively until surgery can be coordinated with an Oculoplastic surgeon. Drainage in patients on blood thinners and in those who are unable to follow commands is contraindicated. Sedation is required for children, the confused patient, and the uncooperative patient. Consult an Ophthalmologist prior to sedating a patient to incise and drain a hordeolum. A recurrent hordeolum should be referred to an Ophthalmologist for biopsy and evaluation of the lesion for a malignancy. Consult an Ophthalmologist prior to the procedure if the hordeolum affects visual acuity or ocular movements.
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SECTION 12: Ophthalmologic Procedures
EQUIPMENT • Buffered local anesthetic solution (e.g., lidocaine with epinephrine and NaHCO3) • 30 gauge, 0.5 inch needle on a 3 mL syringe • 0.5% proparacaine drops • Povidone iodine or chlorhexidine swabs • Small drape with central opening • Sterile 4 × 4 gauze squares • Sterile cotton-tipped applicators • Sterile marking pen • Corneal eye shield • #11 or #15 scalpel blade on a handle • Wescott scissors • Desmarres chalazion clamps, multiple sizes • Meyerhoefer chalazion curettes, multiple sizes • Castro-Viejo forceps • Topical ophthalmic antibiotic ointment without steroids, e.g., erythromycin • Eye pad • Culture swabs • 1-inch tape A chalazion clamp is a device specifically designed to aid in the incision and drainage of a chalazion or hordeolum (Figure 164-3). It is similar to a forceps, except the distal ends are expanded and has a clamp mechanism. One of the distal ends is an open circle used to surround the hordeolum. The other distal end is flat, solid, and acts to prevent injury to underlying structures. Just proximal to the distal expanded ends is a screw mechanism that allows the distal ends to be closed and clamped securely in place.
PATIENT PREPARATION Perform a brief ophthalmic examination including visual acuity, motility, and an anterior segment assessment. Document the size and location of the hordeolum. Explain the procedure, its risks, and benefits to the patient and/or their representative. Place a signed informed consent in the medical record. Many patients are apprehensive when a surgical procedure is performed close to their eye. It is imperative that the patient remains still during this procedure, given that sharp instruments will be exchanged over the globe. A thorough explanation of the surgical steps should alleviate some of the patient’s fears. Consider the use of parenteral sedation or procedural sedation (Chapter 129). Place the patient supine. Support their head with a headrest or a foam doughnut. Place one drop of proparacaine in the cul-de-sac of the affected eye. Mark the circumference of the hordeolum with a sterile skin marker (Figure 164-4A). This is important as the injection of local anesthetic solution will obscure the margins of the hordeolum. Gently wipe the eyelid skin with an alcohol swab. Do not allow the alcohol to get onto the eye. Clean the skin of the eyelid with povidone iodine or chlorhexidine solution. Do not allow these solutions to get onto the eye. If they do get onto the eye, irrigate the eye copiously with normal saline. Arm a 30 gauge needle onto a 3 mL syringe. Draw up 1 mL of buffered local anesthetic solution with epinephrine. Inject the solution around and into the hordeolum (Figures 164-4A & B). Direct the syringe tangential to the skin (for an external hordeolum) or conjunctive (for an internal hordeolum) so as to avoid inadvertent penetration of the globe. Place a corneal shield, if available, over the cornea.
FIGURE 164-3. The chalazion clamp.
TECHNIQUES INTERNAL HORDEOLUM Cleanse and anesthetize the area as described above. Apply a chalazion clamp to the eyelid. Place the loop of the clamp on the conjunctival surface of the eyelid and encompassing the marked edges of the hordeolum (Figure 164-4C). Place the plate of the clamp on the skin surface of the eyelid. Gently close the clamp by turning the screw mechanism. Gently flip the clamp to expose the hordeolum. Make a superficial cruciate incision in the hordeolum with a #11 or #15 scalpel blade (Figures 164-4C & D). Gently insert the chalazion curette to scoop out the purulent material (Figure 164-4D). Alternatively, use a sterile cotton-tipped applicator. Grasp the edge of the inflammatory tissue with the Castro-Viejo forceps. Carefully use Wescott scissors to dissect the planes between the hordeolum and the tarsus (Figure 164-4E). Release the chalazion clamp gently
CHAPTER 164: Hordeolum (Stye) Incision and Drainage
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FIGURE 164-4. Incision and drainage of a hordeolum. A. The hordeolum is identified and a circle is drawn around its margins. A needle is inserted to inject local anesthetic solution. B. Local anesthetic solution is injected into and around the hordeolum. C. A chalazion clamp is applied and an incision is made over the hordeolum. D. Purulent material is expressed for the incision using a chalazion curette. E. Inflammatory tissue is removed.
and remove it from the eyelid. Apply gentle pressure with a gauze square to the incision to control any bleeding. Be careful to not touch the eye with the gauze and cause a corneal abrasion. Culture the expressed purulence. Place ophthalmic erythromycin ointment in the cul-de-sac. Apply a pressure patch over the eye (Chapter 161).
EXTERNAL HORDEOLUM Cleanse and anesthetize the area as described above. Make an incision over the hordeolum with a #11 or #15 scalpel blade. Do not cut the eyelid margin and the underlying tarsus. Gently roll a sterile cotton-tipped applicator over the eyelid skin and toward the incision to express the purulent material. Apply gentle pressure with a gauze square to the incision to control any bleeding. Be careful to not touch the eye with the gauze and cause a corneal abrasion. Culture the expressed purulence. Place ophthalmic erythromycin ointment on the eyelid skin. Apply a pressure patch over the eye (Chapter 161).
ASSESSMENT Palpate the eyelid at the end of the procedure. If a residual pus collection is detected, attempt to express the pus with a cotton-tipped applicator. If this fails, a second incision parallel to the first one is required to completely drain the hordeolum. Do not undermine the delicate eyelid tissues to express the purulent material. While not required, some physicians may perform a repeat fluorescein examination to ensure that they did not cause a corneal abrasion during the procedure.
AFTERCARE The follow-up instructions are simple and straightforward. Instruct the patient to remove the pressure patch in 1 to 2 hours. It was placed to minimize any edema and bleeding from the procedure. If significant bleeding is noted when the patch is removed, the patient should immediately return to the Emergency Department. They should apply a warm compress (or warm rice in a sock) to the eyelid every 3 to 4 hours for the first 24 hours. An eyelid skin incision should remain clean and dry for 24 hours. Prescribe topical ophthalmic antibiotic ointment (e.g., erythromycin if no contraindications exist) to be applied on the skin incision or in the cul-de-sac three times a day for 3 to 4 days. Someone must follow up on the culture results in 12 to 24 hours. If MRSA is detected, the patient must be notified and they require follow-up with an Ophthalmologist within 24 hours or return to the Emergency Department for the consideration of oral antibiotics. Treat any associated blepharitis to prevent the formation of a new hordeolum. The patient should follow up with an Ophthalmologist within 5 to 7 days for an evaluation of the eyelid. They need to be evaluated sooner if the cultures are positive for MRSA. They should immediately be seen by an Ophthalmologist or return to the Emergency Department if any of the following develop: uncontrollable bleeding, increase in eyelid pain and/or swelling, the appearance of yellow or green pus in the eye or on the eyelid, and fever. Oculoplasty referral is warranted to evaluate a recurrent hordeolum or chalazion to rule out malignancy.5 Recurrent bilateral hordeolum may indicate an underlying immunodeficiency (e.g., IgM).6
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COMPLICATIONS Numerous complications are possible both during and as a result of the incision and drainage procedure. Inadvertent injury to the globe (e.g., corneal abrasion or corneoscleral perforation) or eyelid structures (e.g., lacrimal duct or punctum) may occur.7 Early complications include infections such as a cellulitis or conjunctivitis. Most bleeding can be controlled with gentle pressure or tying off of the offending vessel with fine absorbable sutures. Never use a portable hot cautery unit on the eyelid to control bleeding. Uncontrolled bleeding is rare but can occur and will require an Ophthalmologist to control. Late complications occur from excessive scarring at the incision site. If an external incision was made,
the contracting scar can lead to an ectropion, eyelid retraction, uneven eyelid margins, and trichiasis. If an internal incision was made, conjunctival scarring can lead to an entropion and chronic conjunctivitis.
SUMMARY Patients with an acute hordeolum often present to the Emergency Department with a painful, localized, red, and swollen eyelid margin. They should be initially managed conservatively. Subsequent incision and drainage may be required to alleviate patient’s discomfort. The incision and drainage procedure is simple to perform and can be done by the Emergency Physician.
SECTION
Otolaryngologic Procedures
165
External Auditory Canal Foreign Body Removal Rebecca R. Roberts
INTRODUCTION Foreign bodies are commonly found in the external auditory canal (EAC) of children and sometimes in adults.1 Children commonly place small objects such as food (e.g., beans, peas, corn, and seeds) or small round objects (e.g., beads, rocks, and toys) in the EAC.2–5 Adults are more likely to suffer from items used to clean or scratch the ear (e.g., cotton swab, paper, paper clips, and pencil lead) and insects that crawl into the ear.4 The EAC and tympanic membrane (TM) are exquisitely sensitive and delicate.3,6 Foreign bodies in the EAC are extremely irritating to patients; especially live insects that will scratch the TM in an effort to escape. Injuries can occur unless proper care is taken in the removal of EAC foreign bodies.
ANATOMY The EAC is S-shaped and 2.5 cm long in adults.7 The lateral or distal third is cartilaginous, with thick skin. It has more hair follicles, glands, and subcutaneous tissue than the medial or proximal twothirds of the EAC. The medial EAC is bony, with a thinner and more fragile layer of skin.7,8 The narrowed isthmus is located between the cartilaginous and bony portions.2,7 The canal ends medially at the TM, which is situated obliquely to increase the surface area for carrying sound energy to the middle ear.8 The anteroinferior EAC is 0.6 mm longer than the posterosuperior portion.7 Auriculotemporal branches of cranial nerves V, VII, IX, and X and the greater auricular nerve of the cervical plexus supply sensation to the EAC.7
INDICATIONS All EAC foreign bodies must be removed. The only question is how quickly this must be done, who should do it, and which is the safest of available techniques. The method used is individualized to the patient, type of foreign body, Emergency Physician preference and experience, and the availability of an Otolaryngologist. Some foreign bodies are very easily and safely removed with the equipment available in any Emergency Department. Others—due to impaction, large size, sharp edges, location in the canal, involvement of the TM or middle ear structures, or patient age—will require removal under general anesthesia or even an approach to removal from outside the canal.2,6,9 The most urgent indication for immediate removal is an alkaline button battery because of the extensive and severe damage it may cause in a very short time.1 These are most commonly found in the EAC of a young child. There are two mechanisms for the rapid destruction of surrounding tissues by the batteries. The moisture and cerumen in the EAC have a high conductivity, which causes conduction of electric current from the battery and results in localized electrical burns. Local inflammation from those burns will
13
cause fluid exudation into the EAC. This increases the electrical conduction injury and causes the battery to begin leaking alkaline electrolyte solution, which can penetrate deeply into underlying tissues, with resultant liquefaction necrosis.3,10 Therefore, irrigation with water or saline is contraindicated in button battery removal and another technique must be used.1
CONTRAINDICATIONS Rather than contraindications to removal, these can also be thought of as indications for referral to an Otolaryngologist for removal of the foreign body. The major contraindication to removal in the Emergency Department is probable injury with direct removal. Examples are foreign bodies that have perforated or impaled the TM. Removal will cause further damage to the TM as well as potential disruption of the middle ear ossicles and loss of hearing. These foreign bodies require removal under general anesthesia with the aid of an operating microscope.2,3,5,9 Another contraindication is a large object that has impaled itself in the wall of the EAC. Direct removal will require anesthesia and possibly an approach from outside the EAC to avoid denuding the skin of the EAC.3 Finally, objects that are difficult to remove and a patient (usually a young child) who cannot hold still or be held still for the procedure should be referred to an Otolaryngologist.2,5,9 These cases are likely to result in injury if the foreign body is removed in the Emergency Department. Irrigation is almost always safe to attempt.11 The most important contraindication for irrigating the EAC is an acute or chronically ruptured TM.9,11–14 Water forced into the middle ear can lead to otitis media, labyrinthitis, mastoiditis, disruption of the ossicles, and loss of balance or hearing. Some authors recommend alternate methods for any patient who has never had an ear exam to document the integrity of the TM.9,11,12 Completely impacted foreign bodies that leave no space for the irrigant fluid to flow behind it will only be driven deeper into the EAC, making subsequent removal even more difficult.1,15 A relative contraindication for irrigation with water is an organic object, such as a dry bean, seed, or rice.15 Organic foreign bodies will absorb water and swell, making removal more difficult. Irrigation can be attempted if the object is very small and irrigation is expected to rapidly succeed in removal before swelling occurs. Otherwise, irrigate the object with alcohol, remove it with instruments, or extract it with suction. Directly grasping the foreign body with forceps is contraindicated for large or spherical objects that will not allow clear passage of the forceps jaws along its sides. Attempts to grab this type of object will only drive it deeper into the EAC.15
EQUIPMENT Anesthesia • 1%, 2%, or 4% lidocaine solution or gel • 1 mL syringe • 5 mL syringe • 27 or 30 gauge needle • EAC speculum 1063
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FIGURE 165-2. Examples of plastic disposable curettes. Note the variety of head shapes. (Photo courtesy of Bionix Medical Technologies, Toledo, OH.)
FIGURE 165-1. Instruments used for removal of foreign bodies from the external auditory canal. A. Cerumen loop. B. Right-angle ball hook. C. Alligator forceps. D. Hartman forceps. E. Frazier suction catheter.
Irrigation • 10 or 20 mL syringe • Butterfly catheter with any size needle (after needle and most of tubing is cut off) • Kidney basin • One Chux or other water barrier • Tap water or saline at or slightly above body temperature6,8,11,13,14 Alternate Irrigation Equipment8 • Plastic portion of 18 gauge angiocatheter • Dental jet-irrigation device (e.g., Water-Pik) • DeVilbiss irrigator and a compressed air source • Metal ear syringe
FIGURE 165-3. Lighted, disposable, and single patient use devices to aid in cerumen removal. From left to right: articulating curette, open loop curette, and grasping forceps. (Photo courtesy of Bionix Medical Technologies, Toledo, OH.)
Instruments to Pass Behind Object and Pull It Out (Figures 165-1 to 165-4) • Ear curettes or cerumen spoon, metal or disposable plastic • Wire loop • Blunt or ball right-angle hook Instruments Used to Grasp Object Directly (Figures 165-1 & 165-3) • Alligator forceps • Hartman forceps • Lighted forceps (Bionix Medical Technologies, Toledo, OH)
FIGURE 165-4. The EasiEar metal curette (Splash Medical Devices LLC, Atlanta, GA).
CHAPTER 165: External Auditory Canal Foreign Body Removal
Suction • Frazier suction tips • Intravenous tubing with flange created at tip using a heat source • Vacuum or suction source • Connection tubing • Hemostat Cyanoacrylate Glue16 • Ear speculum • Cyanoacrylate wound/tissue glue or Superglue • Paper clip or cotton-tipped applicator • Superglue removal equipment Cyanoacrylate Glue Removal17 • Acetone to debond glue from skin • Cotton balls • Cotton-tipped applicators • Irrigation or instruments for final removal Commercially Available Devices • Hognose otoscope tip • Katz extractor Pediatric Immobilization • Sheets • Commercial immobilization device (e.g., Papoose board)
PATIENT PREPARATION Explain the procedure and potential complications to the patient and/or their representative. The discussion should include discomfort, dizziness, minor bleeding, postprocedural otitis externa, and TM perforation. Discuss the importance of remaining still during the procedure. Warn the patient that they may experience an occasional loud noise, especially if suction is used. The most convenient position for adult patients is to remain seated with the affected ear facing the Emergency Physician. Children can sit on the lap of a parent or attendant with the affected ear facing the Emergency Physician. The parent or attendant should wrap one arm around the child’s arms and body while stabilizing the head with their other arm.3 Smaller children can be swaddled in a papoose made from a sheet and tape or a commercial immobilization device.3 Place the patient supine with their face toward the ceiling. Do not place the patient with the affected ear facing up, as this may cause the foreign body to move farther into the EAC. All removal techniques require the EAC to be straightened before inserting any device. In the adult, this is accomplished by pulling the pinna up and back while simultaneously pulling it straight out from the head.8 In the small child, pull the pinna down, back, and slightly out from the head.6,8 The patient may require anesthesia of the EAC. Fill the EAC with 5 to 10 mL of 1% lidocaine using the syringe tip, an angiocatheter without the needle, or a butterfly catheter with the needle cut off. This will result in substantial but short-lived topical anesthesia for the procedure.15 If the effect wears off before the procedure is complete, the topical application of lidocaine can be repeated as needed or longer-acting agents may be used. Although usually not necessary, local anesthetic solution may be injected to provide analgesia. Fill a 1 mL syringe with local anesthetic solution and apply a 2-inch long, 27 or 30 gauge needle. Position a plastic or metal ear speculum into the EAC. Insert the needle
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through the speculum. Inject 0.25 mL subcutaneously in the superior and inferior quadrants of the EAC distal to the isthmus. If needed, all four quadrants can be injected.15 Refer to Chapter 168 for a complete discussion of EAC anesthesia. A final option is to use procedural sedation and analgesia (Chapter 129) to control the patient and remove the foreign body.24
TECHNIQUES PRECAUTIONS FOR USING INSTRUMENTS IN THE EAC There are two major precautions the Emergency Physician must take to avoid pushing the foreign body further into the EAC or causing damage to the EAC and TM. First, the procedures must be performed under direct vision. Second, the hand holding the instruments must remain firmly in contact with the patient’s head at all times to stabilize the hand and avoid abrading or lacerating the EAC wall or damaging the TM should the patient abruptly move.2,8 Even a very cooperative patient may move due to an involuntary reflex cough.6
IRRIGATION Irrigation is the safest method of foreign body removal.2,8,9,18 It is most successful for nonimpacted and smaller foreign bodies. Tuck a water barrier into the patient’s gown or collar. Place a kidney basin under the ear and against the cheek to catch the irrigation solution and the foreign body. Instruct the patient or an assistant to hold the basin in place. Attach a butterfly needle to a 10 or 20 mL syringe. Cut the needle and most of the tubing, leaving only 1 to 2 cm of the tubing (Figure 165-5). This remaining tubing will usually be curved, which is optimal for precisely directing the irrigation stream. Others use a 14 or 16 gauge plastic angiocatheter.19 It is important to remember that wider diameter instruments deliver fewer pounds per square inch of pressure with a reduced chance of injury.19 Draw up body temperature or slightly warmer tap water or saline into the syringe. Be sure to use only body temperature or slightly warmer fluid to avoid complications from caloric stimulation.8,11 Straighten the EAC by manipulating the pinna. Insert the butterfly tubing or angiocatheter 1 cm into the EAC with the tip aimed upward and away from the foreign body (Figure 165-5).13 Rapidly inject the irrigating solution. This will cause the fluid to shoot past the foreign body, bounce off the TM, and carry the foreign body out of the EAC along with the irrigating solution.2,9 Care must be taken to make sure that the irrigation stream and foreign body can easily exit the EAC, to prevent an increase in hydrostatic pressure, which could damage the TM.12 Sometimes irrigation will not completely remove the foreign body but move it more laterally, where an instrument can be safely used to grasp and remove it. All water or saline should be removed from the EAC to prevent an otitis externa.8,11 Many physicians have used mechanical dental irrigation devices (e.g., Water-Pik) to irrigate the EAC and remove either cerumen or a foreign body. These devices shoot a stream of fluid from its tip. While they will often remove the cerumen or foreign body, the direct fluid stream can rupture a TM.11,19,22 The OtoClear Ear Irrigation Tip (Bionix Medical Technologies, Toledo, OH) is an improvement for EAC irrigation (Figure 166-6). This device is designed as disposable and single patient use. It attaches to the Luer hub of a syringe. The OtoClear tip can also be attached to a spray bottle or dental irrigating device, allowing these devices to be safely used. When inserted into the EAC, its flared base fits snugly and prevents it from being inserted too far. Holes in the base allow for the egress of irrigation fluid into the kidney basin
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FIGURE 165-5. Irrigation with butterfly catheter tubing attached to a syringe. The stream of fluid is aimed toward the top of the external auditory canal and above the foreign body.
held against the skin. The OtoClear tip directs fluid toward the walls of the EAC (Figure 166-6). While this prevents damage to the TM, in some cases it may not provide enough flow or pressure to remove a foreign body.
SLIDING A FOREIGN BODY OUT WITH AN INSTRUMENT FROM BEHIND This technique requires either a cerumen spoon or wire loop for small objects or a right-angle hook for larger ones (Figures 165-1A, B, & 165-4). Straighten the EAC by manipulating the pinna. Pass the tip of the instrument over and behind the foreign body with the spoon, loop, or hook in the same plane as the EAC wall. Rotate the instrument 90° to bring the loop or hook behind and directly in contact with the back (medial) side of the foreign body. Gently pull the instrument out of the EAC, pulling the foreign body out with it.2,8 Take extra care so that the EAC and TM are not injured during the instrument insertion or removal. The EasiEar Disposable Comfort Curette (Splash Medical Devices LLC, Atlanta, GA) is an improvement to the standard disposable plastic curette (Figure 165-4). It is a stainless steel, single patient use, and disposable curette. The rounded wire head is smooth. It lacks the jagged and sharp plastic edges that are often found on molded plastic curettes. The EasiEar has no abrasive edges, seams, or surfaces to potentially abrade the EAC. This design may prevent EAC abrasions and lacerations, and procedure-related bleeding. The spring wire shaft provides some flexibility and enhanced maneuverability when compared to molded plastic curettes, making the foreign body removal process easier. The angled head and flexible shaft allow it to be manipulated within the EAC to remove a foreign body.
GRASPING FOREIGN BODIES WITH FORCEPS If this maneuver is to be successful, there must be sufficient space between the EAC wall and the foreign body, or a projecting edge that can be grasped, so as to avoid pushing it further into the EAC.2,4,9 This technique is contraindicated if the object is spherical
and located against the TM, which can be injured during the procedure.4 The most commonly used instruments include the alligator forceps (Figure 165-1C) and the Hartman forceps (Figure 165-1D). A lighted forceps (Bionix Medical Technologies, Toledo, OH) may also be used (Figure 165-3). Straighten the EAC by manipulating the pinna. Insert the forceps into the EAC and grasp the foreign body (Figure 165-6). Gently withdraw the instrument and the foreign body, taking care not to abrade the EAC wall. If the foreign body is located too far medially or instrumentation would cause pain or damage to the TM, irrigation may be able to move the foreign body laterally for subsequent grasping.
SUCTION REMOVAL Frazier suction catheters (Figure 165-1E) are most useful with small foreign bodies. Otherwise, this technique will be unsuccessful or will push the object farther into the EAC. Attach the Frazier suction catheter to the suction tubing. Turn on the suction source. Straighten the EAC by manipulating the pinna. Gently insert the catheter into the EAC. Place a thumb over the hole in the catheter handle to direct the suction through the tip of the catheter. Gently advance the suction catheter until the tip is in contact with the foreign body. Withdraw the Frazier suction catheter and foreign body from the EAC. For impacted smooth, spherical objects, suction with plastic intravenous tubing can be used.1,20 Cut a short length of plastic intravenous tubing and attach one end to the suction source. Fashion the other end into a small flange shape using a heat source and any metal object with a rounded end, such as the tip of a hemostat or larger clamp. Heat the jaws of the hemostat and insert them into the plastic tubing just enough to create a flange. Turn on the suction source. Place a hemostat onto the tubing to temporarily clamp the suction tubing. Straighten the EAC by manipulating the pinna. Gently advance the flange tip into the EAC until it contacts the foreign body, taking care not to push it inward (Figure 165-7). Remove the hemostat from the tubing to activate the suction. Gently but quickly remove the tubing and attached foreign body from the EAC.
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FIGURE 165-6. Forceps removal of a foreign body. A. Hartman forceps. B. Alligator forceps.
CYANOACRYLATE GLUE—ASSISTED REMOVAL Cyanoacrylate glue can be used to extract impacted spherical objects that allow no space for irrigation or instrument removal and are located laterally or distally in the EAC.1,16 However, this technique can be fraught with complication.17 Always use an ear speculum to decrease the chance of gluing the foreign body to the EAC or TM and to prevent creating a glue foreign body. Insert an ear speculum into the EAC with the tip near the foreign body. Do not touch the foreign body with the speculum so as to prevent it from being impacted. The ear speculum will prevent the Emergency Physician from touching the EAC with glue. Obtain a long, thin object (e.g., straightened paper clip or the stick end of a cotton-tipped applicator). Moisten the tip of the paper clip or applicator stick with a very tiny amount of cyanoacrylate glue. A larger amount can drop off into the EAC. Insert the ear speculum. Straighten the EAC by manipulating the pinna.
Quickly insert the paper clip or applicator stick through the ear speculum, before the glue dries, until it just touches the foreign body. Maintain this position for 30 to 60 seconds to allow bonding of the glue to the foreign body. Remove the paper clip or applicator stick with the foreign body attached and the speculum all together.
REMOVAL OF CYANOACRYLATE GLUE For either iatrogenic or patient-introduced cyanoacrylate glue, debonding from the patient’s tissues by acetone must precede the removal.1,17 Failure to do this will result in tearing of the skin or TM. Do not apply acetone if the TM cannot be visualized or is not intact.11 Infuse acetone into the EAC using cotton balls or swabs. Allow it to remain in the EAC for 5 minutes. Since acetone evaporates rapidly, several applications may be necessary. Once the glue mass is free, it can be removed by irrigation, instruments, or suction.
HOGNOSE OTOSCOPE TIP
FIGURE 165-7. Suction removal of a foreign body.
The Hognose (IQDr. Incorporated, Manitou Springs, CO) is a disposable, latex free, and single-use device that attaches to a standard otoscope (Figure 165-8). It comes in three sizes (3, 4, and 5 mm), each with a color-coded tip. The size represents the cup size at the tip of the device. The tip is soft, self-molding, and looks like the nose of a hog. It has an insufflation port and suction tubing attached to its side. The adapter on the suction tubing attaches to standard wall suction tubing. Attach the Hognose to the otoscope similar to attaching a disposable speculum to an otoscope. Turn on the otoscope light source. Attach the hognose tubing to suction tubing and a suction source. Turn the suction source on to low or medium. Grasp the otoscope with your dominant hand. Straighten the EAC by manipulating the pinna. Insert the Hognose into the EAC while visualizing the foreign body through the otoscope head. When the tip of the Hognose is just next to the foreign body, place an index finger over the insufflation port to engage the suction at the device tip. Gently advance the otoscope until the tip of the Hognose is against and attached to the foreign body. If you suddenly see black through the otoscope, the soft tip has collapsed on itself. Remove the finger over
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FIGURE 165-10. The Katz Extractor. The balloon at the tip inflates and deflates by pushing and releasing the plunger, respectively. (Photo courtesy of InHealth Technologies, Carpinteria, CA.)
FIGURE 165-8. The Hognose otoscope tip attached to an otoscope. (Photo courtesy of IQDr. Incorporated, Manitou Springs, Co.)
the insufflation port and re-approach the object. While maintaining suction, withdraw the Hognose with the foreign body attached.
GATORNOSE OTOSCOPE TIP The Gatornose (IQDr. Incorporated, Manitou Springs, CO) is a disposable, latex free, and single-use device that attaches to a standard otoscope (Figure 165-9). It twists onto an otoscope like a speculum. It comes with three different jaw types that attach to the body
of the device. These jaws are small flat jaws, large flat jaws, and open loop jaws. A trigger on the body of the device controls jaw opening and closing. Attach the Gatornose to the otoscope similar to attaching a disposable speculum to an otoscope. Turn on the otoscope light source. Grasp the otoscope with your dominant hand. Insert the ring finger into the trigger. Pull the trigger to close the Gatornose jaws. Straighten the EAC by manipulating the pinna. Gently insert the Gatornose jaws just into the EAC. Push the trigger to open the Gatornose jaws and be able to view through the otoscope. Gently advance the otoscope while visualizing the foreign body through the otoscope head. Position the jaws above and below or anterior and posterior to the foreign body. Pull the trigger to close the jaws onto the foreign body. Withdraw the otoscope with the foreign body in the jaws of the Gatornose.
KATZ EXTRACTOR The Katz Extractor Oto-Rhino Foreign Body Remover (InHealth Technologies, Carpinteria, CA) is a device designed to extract foreign bodies from the nasal and auditory passages (Figure 165-10). It is a disposable single-use device consisting of a balloon-tipped catheter attached to a syringe. Always test the device before using it. Push the plunger to inflate the balloon and inspect it for any air leaks. Release the plunger to deflate the balloon. Grasp the device with the dominant hand (Figure 165-11). Gently insert the catheter along the wall of the EAC until the balloon is just past the foreign body (Figure 165-11A). Inflate the balloon by depressing the plunger on the syringe (Figure 165-11B). Withdraw the catheter and foreign body from the EAC while maintaining the balloon in the inflated state (Figure 165-11C). If the foreign body has a central hole (e.g., candy or bead), insert the catheter through the hole rather than behind it.
LIVE INSECT REMOVAL
FIGURE 165-9. The Gatornose otoscope tip attached to an otoscope. Note the three types of jaws that are available to snap onto the base of the device. (Photo courtesy of IQDr. Incorporated, Manitou Springs, Co.)
A live insect in the EAC is one of the most painful and upsetting foreign bodies. The patient suffers as the insect moves, vibrates, tries to flap its wings, or pushes against the sensitive TM in an effort to escape.3 In the past, mineral oil was infused to smother and kill the insect prior to removal.4,15,21 However, this method has several disadvantages. A significant time passes while the patient is still suffering and the insect dies. Due to being stuck in the viscous oil, the insect is more difficult to remove and frequently breaks into multiple pieces. The EAC is also now impossible to anesthetize with a local infusion of lidocaine, which is repelled by the oil. A preferred technique is to immobilize the insect with an infusion of 1% lidocaine into the EAC.21 A topical anesthetic composed of benzocaine and antipyrine (e.g., Auralgan) may also be used. The
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can be used to move the dead insect more distally in the EAC, followed by instrument removal. It is recommended that the EAC be inspected and irrigated after the insect is removed to make sure that no tiny parts of the insect remain in the EAC, as they can cause an otitis externa.3
ASSESSMENT After the foreign body has been removed, it is crucial to reexamine the patient to confirm that the EAC, TM, and hearing are all normal and have not been damaged.3,4,18 In children, but also adults with mental or psychiatric problems, it is prudent to examine the other ear, the nostrils, and any other orifice that may be harboring an unsuspected foreign body.3–5 Any remaining irrigation fluid in the EAC should be removed to prevent an otitis externa.8
AFTERCARE Most authors recommend prescribing several days of topical otic drops to prevent or treat subclinical otitis externa, which is often precipitated by abrasion of the EAC or inflammation due to foreign body impaction.3 Often recommended are topical combinations of antibiotics and steroids in solution or suspensions. Commonly prescribed agents include otic quinolones, Corticosporin Otic, Otic Domeboro, Otobiotic, Pediotic suspension, and VoSol to name a few. Consult an Otolaryngologist for patients with injuries, hearing deficits, severe otitis externa, or in whom removal was unsuccessful. Otherwise, the patient can receive follow-up with their Primary Care Physician in 48 to 72 hours. Instruct the patient in the proper application of ear drops. They should return to the Emergency Department if they develop ear pain, ear discharge, fever, decreased hearing, vertigo, headache, or a stiff neck.
COMPLICATIONS
FIGURE 165-11. The Katz Extractor removing an EAC foreign body. A. The device is inserted until the balloon is just past the foreign body. B. The balloon is inflated. C. The Katz extractor is removed with the balloon inflated and the foreign body is removed.
local anesthetic results in the insect becoming inert much more quickly than with oil. The EAC and TM are thus anesthetized for patient comfort and the immobilized insect is more likely to be removed in a single piece than with mineral oil. The insect can now be easily removed by irrigation or instrument removal. Sometimes both techniques are used. Irrigation
Numerous complications can result from the removal of a foreign body from the EAC.3–5,8,11,12,14,15,18 The complication rate for irrigation is reported as 1 per 1000 cases.14,18 It is higher for all other techniques.8,11 Irrigation can push a foreign body further into the EAC. If the irrigating solution is cold, caloric stimulation can result in vomiting, vertigo, bradycardia, and syncope.1,11 Middle ear debris can be forced through a preexisting or iatrogenic TM defect, resulting in an otitis media, damage to the ossicles, labyrinthitis, mastoiditis, loss of hearing and balance, or a central nervous system infection.9,11–14 Otitis externa can result from abrasions to the EAC or water left behind after irrigating. Butterfly tubing is less likely than an angiocatheter to damage the EAC or TM because of its more pliable nature, larger diameter, and curved tip. It is known that mechanical dental irrigation devices, even at low pressures, can rupture the TM.11,19,22 For this reason, they are not recommended for the removal of foreign bodies from the EAC. Instrumentation and suction should be used with caution to prevent secondary injury. This includes EAC lacerations or abrasions, TM rupture, pushing of foreign bodies further into the EAC, and disruption or removal of the ossicles. Abrasions or lacerations to the EAC can result in an otitis externa. Cyanoacrylate glue can cause complications and is the least favorite technique of this author. The Emergency Physician may glue their fingers together or to the instruments. The foreign body may be glued to the pinna, EAC, or the TM. Removal of the glue can abrade and irritate the skin and/or TM.
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SUMMARY
INDICATIONS
Foreign bodies in the EAC are common. With adequate anesthesia, careful planning, and gentle handling, most foreign bodies can be successfully removed in the Emergency Department from the EAC.23 The removal techniques require equipment that is readily available in the Emergency Department. The removal techniques are easy to perform, quick, and simple to learn. An impacted button battery is a true emergency and requires immediate removal. An emergent consultation with an Otolaryngologist is required if the button battery cannot be removed or if any evidence of injury is present after the button battery has been removed.
Recently, the term “impaction” has been defined more clearly as cerumen that causes patient symptoms or prevents a necessary examination of the EAC or TM.4 The primary indication for removal of cerumen is symptomology of impaction.2,4 The most common complaint is hearing loss, which is often abrupt and expressed as a “blocked ear.” Hearing remains normal or nearly so as long as there is a small space in the EAC through which sound can pass and cause vibration of the TM. The hearing loss becomes subjectively significant when the canal is completely obstructed or when the TM is compressed by cerumen and cannot freely move.4,6,8 Other typical symptoms of cerumen impaction include fullness, itching, odor, pain, tinnitus, vertigo, unsteady gait, or reflex cough due to vagus nerve stimulation.4,6,7 Other indications for removing cerumen include the need to examine the ear canal and TM or to test hearing.4,8,9 Cerumen can cause feedback sound loops in those with hearing aids or damage the appliance.4
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Cerumen Impaction Removal Rebecca R. Roberts
INTRODUCTION Removal of impacted cerumen is one of the most common otolaryngologic procedures performed by nonotolaryngologists.1 This procedure is also believed to be the most common cause of iatrogenic otolaryngologic complications referred to specialists.2 Approximately 8 million ears are irrigated annually in the United States to remove cerumen.3,4
ANATOMY AND PATHOPHYSIOLOGY The S-shaped external auditory canal (EAC) is 2.5 cm long in adults.5 The lateral or distal third is cartilaginous, with thicker skin, more hair follicles, glands, and subcutaneous tissue than the medial or proximal two-thirds, which is bony and has a thinner, more fragile layer of skin.5,6 The narrowed isthmus is located between the cartilaginous and bony portions.5 The canal ends medially at the tympanic membrane (TM), which is situated obliquely to increase the surface area for carrying sound energy to the middle ear.6 The anteroinferior EAC is 0.6 mm longer than the posterosuperior portion.5 Auriculotemporal branches of cranial nerves V, VII, IX, and X and the greater auricular nerve of the cervical plexus supply sensation to the EAC.5 Cerumen is a mixture comprising secretions of the ceruminous glands of the lateral two-thirds of the EAC, the pilosebaceous glands located at the roots of EAC hairs, and sloughed squamous epithelial cells.5,7 Cerumen forms a barrier against infection, has antimicrobial activity, and protects the skin of the EAC as it is water repellant. It is expelled naturally by migration assisted by chewing movements.7,8 There are many reasons for cerumen to become impacted.4,6,7 The most common is self-cleaning with cotton-tipped applicator swabs that can push cerumen further into the EAC. The abundant hairs in the EAC, more common in males than females, can obstruct cerumen migration. A small (especially in children), tortuous, or scarred EAC will obstruct cerumen migration. Some people produce large quantities of cerumen. Diseases such as Parkinson’s can alter the consistency of the cerumen and inhibit its migration. Hearing aids, stethoscope earpieces, or any other object in the EAC may compact the cerumen. Deficits in the substances that cause sloughed squamous epithelial cells to separate will inhibit the movement of cerumen. Nonimpacted cerumen exposed to water can swell and obstruct the EAC.
CONTRAINDICATIONS There are several general contraindications to cerumen removal. An uncooperative patient or young patient that cannot follow instructions or be safely restrained can suffer an iatrogenic injury. Previous ear surgery with scarring of the EAC or TM risks iatrogenic injury. A known or suspected cholesteatoma is a contraindication to cerumen removal. Do not attempt removal if the anatomy of the EAC or TM cannot be clearly defined or is distorted. The remaining contraindications to cerumen removal are specific to each removal technique. Nearly all cerumen can be safely removed by using one of the techniques listed. Often, two or more techniques can be used together with increased success.6,9 The most important contraindication for EAC irrigation is an acute or chronically ruptured TM.4,7–12 Fluid forced into the middle ear can lead to otitis media, labyrinthitis, mastoiditis, disruption of the ossicles, and loss of balance or hearing.4,10,12 Some authors recommend alternate methods for any patient who has never had an ear exam to document the integrity of the TM.9,10 Most patients can provide the information of having a history of a ruptured TM. A relative contraindication is moderate to severe otitis externa.4,7,8 The major contraindication to instrument removal is a patient, usually pediatric, who is so uncooperative that injury to the EAC or TM is likely to occur with movement.6,12,13 The second contraindication is cerumen pushed directly against the TM. In these circumstances, the TM can be abraded or perforated during cerumen removal with instruments. The major contraindication to suction removal is a single, hard, irregular, and impacted cerumen plug. Suction will be unsuccessful. Suction works best if there are multiple tiny cerumen fragments or very soft cerumen.9 Cerumen softening or cerumenolytic agents should not be used if the patient has a ruptured TM. Other contraindications to softening agents are an allergy to the agent or an otitis externa.4,7,14,15
EQUIPMENT Anesthesia • Local anesthetic solution or suspension (e.g., viscous lidocaine, lidocaine solution, or Auralgan) • 3 mL syringe Irrigation • 10 to 20 mL syringe • Butterfly catheter with any size needle
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• Kidney basins • Chux or other water barrier • Tap water or saline at or slightly above body temperature5,6 Alternate Irrigation Equipment4 • Plastic portion of 18 gauge angiocatheter • Oral jet irrigation (Water-Pik); no longer recommended (see “Complications,” below) • DeVilbiss irrigator and a compressed air source • Metal ear syringe Instruments to Separate and Loosen Cerumen (Figures 166-1 to 166-4) • Ear curettes or cerumen spoon, metal or disposable plastic • Wire loop • Blunt or ball right-angle hook
FIGURE 166-2. Examples of plastic disposable curettes. Note the variety of head shapes. (Photo courtesy of Bionix Medical Technologies, Toledo, OH.)
Instruments to Grasp Cerumen Directly (Figures 166-1 & 166-3) • Alligator forceps • Hartman forceps • Lighted forceps (Bionix Medical Technologies, Toledo, OH) Suction • Frazier suction catheters • Suction source • Connection tubing • Hemostat
FIGURE 166-3. Lighted, disposable, and single patient use devices to aid in cerumen removal. From left to right: articulating curette, open loop curette, and grasping forceps. (Photo courtesy of Bionix Medical Technologies, Toledo, OH.)
FIGURE 166-1. Instruments used for removal of cerumen from the external auditory canal. A. Cerumen loop. B. Right-angle ball hook. C. Alligator forceps. D. Hartman forceps. E. Frazier suction catheter.
FIGURE 166-4. The EasiEar metal curette (Splash Medical Devices LLC, Atlanta, GA).
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Cerumen Softening Agents • Warm tap water • Hydrogen peroxide • Olive, mineral, vegetable, or almond oil • 5%, 10%, or 15% sodium bicarbonate solution • Commercial agents (e.g., Cerumenex, Cerumol, Auralgan, and Waxsol) • Colace • Glycerine • Alcohol • Propylene glycol Pediatric Immobilization • Sheets • Commercial immobilization device (e.g., Papoose board)
PATIENT PREPARATION Explain the procedure and potential complications to the patient and/or their representative. The discussion should include discomfort, dizziness, minor bleeding, postprocedural otitis externa, and TM perforation. Discuss the importance of remaining still during the procedure. Warn the patient that they may experience an occasional loud noise, especially if suction is used. The most convenient position for adult patients is to remain seated with the ear facing the Emergency Physician. Children can sit on the lap of a parent or attendant with the affected ear facing the Emergency Physician. The parent or attendant should wrap one arm around the child’s arms and body while the stabilizing the head with their other arm.16 Smaller children can be swaddled in a papoose made from sheets and tape or a commercial immobilization device.16 Turn the affected ear toward the ceiling and fill the EAC with 5 to 10 mL of local anesthetic solution or suspension using the syringe tip, an angiocatheter, or a butterfly catheter with the needle cut off. This will result in substantial but short-lived topical anesthesia for the procedure.17 If the effect wears off before the procedure is
complete, the topical application of local anesthetic can be repeated as needed or longer-acting agents may be used. All cerumen removal techniques require the EAC to be straightened. In the adult, this is accomplished by pulling the pinna slightly up and back while simultaneously pulling it straight out from the head.6 In the small child, pull the pinna down, back, and slightly out from the head.6,18
TECHNIQUES PRECAUTIONS FOR USING INSTRUMENTS IN THE EAC There are two major precautions the Emergency Physician must take to avoid pushing cerumen further into the EAC or causing damage to the EAC and TM. First, the procedures must be performed under direct vision.6 Second, the hand holding the instrument must remain firmly in contact with the patient’s head at all times to stabilize the hand and avoid scrapping the canal wall or puncturing the TM should the patient move.6,15 Even a very cooperative patient may move due to an involuntary reflex cough.18
IRRIGATION Irrigation is the safest and easiest method of removing cerumen, and is usually successful.2,4,6,10,15 It is less likely to lacerate or damage the EAC or TM than other techniques. It is also the technique most commonly used by nonotolaryngologists. Place a kidney basin under the affected ear and against the patient’s cheek to catch the exiting irrigation solution and cerumen. Instruct the patient or an assistant to hold the basin in place. This author’s favorite device for irrigating is to cut the needle and most of the tubing off a butterfly needle, leaving only 1 to 2 cm of tubing (Figure 166-5).13 This remaining tubing will usually be curved, which is optimal for precisely directing the irrigation stream. Others use a 14 or 16 gauge plastic angiocatheter.12 It is important to remember that wider diameter instruments deliver fewer pounds per square inch of pressure with reduced chance of injury.12 Attach the irrigation tubing or angiocatheter onto a 10 or 20 mL syringe. Draw up body temperature normal saline or tap water into the
FIGURE 166-5. Irrigation with butterfly catheter tubing attached to a syringe. The stream of fluid is aimed toward the top of the external auditory canal and above the cerumen.
CHAPTER 166: Cerumen Impaction Removal
FIGURE 166-6. The OtoClear Ear Irrigation Tip. (Photo courtesy of Bionix Medical Technologies, Toledo, OH.)
syringe. Insert the butterfly tubing or angiocatheter 1 cm into the EAC with the tip aimed in a direction opposite to the location of the cerumen8 (Figure 166-5). This will cause the water to shoot past the cerumen, bounce off the TM, and force the cerumen out of the EAC along with the irrigating solution.10 If there is no obvious break in the cerumen, direct the stream superiorly or slightly anterior and superiorly.4,10 Care must be taken to make sure that the irrigation stream can easily exit the EAC, to prevent an increase in hydrostatic pressure, which could damage the TM.9 Use only body temperature, or slightly warmer, fluid to avoid caloric stimulation symptoms.4 Irrigation will often have to be repeated numerous times, but persistence is usually rewarded with success.6 Irrigation will sometimes have to be combined with either cerumen softening agents, manual separation of cerumen from the EAC wall, or direct grasping of a partially dislodged cerumen plug.4,6 Many physicians have used mechanical dental irrigation devices (e.g., Water-Pik) to irrigate the EAC and remove cerumen. These devices shoot a stream of fluid from its tip. While they will often remove the cerumen, the direct fluid stream can rupture a TM.3,4,12,20 The OtoClear Ear Irrigation Tip (Bionix Medical Technologies, Toledo, OH) is an improvement for EAC irrigation (Figure 166-6). This device is designed as disposable and single patient use. It attaches to the Luer hub of a syringe. The OtoClear tip can also be attached to a spray bottle or dental irrigating device, allowing these devices to be safely used. When inserted into the EAC, its flared base fits snugly and prevents it from being inserted too far. Holes in the base allow for the egress of irrigation fluid and cerumen into the kidney basin held against the skin. The OtoClear tip directs fluid toward the walls of the EAC (Figure 166-6). This prevents damage to the TM.
INSTRUMENT REMOVAL: SEPARATION OF CERUMEN FROM THE EAC WALL This technique is a useful adjunct to irrigation and/or instrument removal.15 Sometimes the cerumen is firmly pressed against the EAC wall in all visible directions. Irrigation will not work or may
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even worsen the situation by pushing the cerumen further into the EAC. Use either cerumen curettes (Figures 166-2 to 4), loops (Figure 166-1A), right-angle hooks (Figure 166-1B), or wires to gently separate the cerumen from the EAC wall and compress it into the center of the lumen.9 The EasiEar Disposable Comfort Curette (Splash Medical Devices LLC, Atlanta, GA) is an improvement to the standard disposable plastic curette (Figure 166-4). It is a stainless steel, single patient use, and disposable curette. The rounded wire head is smooth. It lacks the jagged and sharp plastic edges that are often found on molded plastic curettes. The EasiEar has no abrasive edges, seams, or surfaces to potentially abrade the EAC. This design may prevent painful cerumen removal, EAC abrasions and lacerations, and procedure-related bleeding. The spring wire shaft provides some flexibility and enhanced maneuverability when compared to molded plastic curettes, making the cerumen removal process easier. The best place to start is superiorly. The cerumen should not be pulled out with the same movement, as this can abrade the EAC.15 Once there is a visible passage to the TM, irrigation as described above is highly successful and safe. Alternatively, separation of the cerumen from the EAC wall can be performed circumferentially, all the way around the cerumen plug. This results in a cerumen plug freely suspended in the EAC, which can easily be removed by irrigation, pulled out with a right-angle hook, or grasped with forceps.15
INSTRUMENT REMOVAL: SLIDING CERUMEN OUT WITH INSTRUMENTS FROM BEHIND This technique requires either a cerumen spoon (Figure 166-1A), a wire loop for small cerumen particles, a right-angle hook (Figure 166-1B) for larger quantities, or an EasiEar curette (Figure 166-4). Separate the cerumen from the EAC wall as described above. Position the instrument with the loop or hook in the same plane as the EAC wall. Insert the tip of the instrument into the EAC above and just beyond the cerumen to be removed. Rotate the instrument 90° to bring the loop or hook behind and directly in contact with the back (medial) side of the cerumen. Gently pull the instrument out of the EAC, pulling the cerumen out with it.6 Take care not to abrade the EAC wall with the instrument.
INSTRUMENT REMOVAL: GRASPING CERUMEN WITH FORCEPS FOR REMOVAL To be successful, there must be sufficient space for the jaws of the forceps on both sides between the EAC wall and the cerumen, or a lateral leading edge that can be grasped. Separate the cerumen from the EAC wall as described above. Insert the forceps into the EAC. Grasp the cerumen with the jaws of the Hartman (Figure 166-7A) or alligator forceps (Figure 166-7B). Gently withdraw the forceps, taking care not to abrade the EAC wall. If the cerumen is located too far medially or instrumentation would cause pain or damage to the TM, irrigation can move the cerumen plug laterally for subsequent grasping with a forceps. For an optimal outcome, one may need to alternate irrigation and instrument removal to remove all of the cerumen plug safely and completely.4,6 For example, irrigation may gently soften or loosen the plug. A cerumen loop or curette can then be used to separate it from the EAC wall. Irrigation can be used again to move it more laterally. Finally, a forceps or hook can be used to remove the cerumen plug from the EAC.
SUCTION REMOVAL This technique requires soft cerumen or multiple small flakes.9 Use the same preparations and precautions described above. Attach the
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FIGURE 166-7. Forceps removal of cerumen. A. Hartman forceps. B. Alligator forceps.
Frazier suction catheter or suction tubing to the suction source. Turn on the suction source. Insert the suction catheter into the EAC. Gently advance the suction catheter until the tip is in contact with the cerumen (Figure 166-8). If using a Frazier suction catheter, place the thumb over the hole on the catheter shaft to direct the suction through the tip of the Frazier catheter. Gently advance the Frazier catheter until its tip is in contact with the cerumen. Withdraw the suction catheter or Frazier catheter and cerumen from the EAC. Usually the tip must be withdrawn and cleaned continuously, because most cerumen will plug the suction tip. For additional safety, insert the suction catheter through a plastic otoscope speculum and withdraw both together.
CERUMEN SOFTENING AGENTS If the cerumen is so impacted and hard that the above techniques are likely to cause pain and/or injury or if the cerumen cannot be removed, apply a “cerumenolytic” or cerumen softening agent. After
the cerumen has softened, it can be removed using the techniques described above. Many studies have compared different agents and most are surprisingly comparable in their effectiveness.1,4,7,14 In fact, even water or saline is effective for cerumen softening and disintegration.1,4,7,14 This may explain why persistent irrigation is so frequently successful. The more commonly available agents in the Emergency Department are listed in the “Equipment” section. Fill the EAC with one of the cerumen softening agents. Insert a cotton ball into the opening of the EAC to prevent the agent from leaking out. Apply the agent to the contralateral EAC if indicated. An alternative is to place the patient lying on their side with the affected ear facing upward. Insert the agent into the EAC. The agent will not leak out if the patient remains in this position. The disadvantage of placing the patient on their side is that only one ear can be worked on at a time. Most authors recommend waiting 15 to 30 minutes after the application of the cerumen softening agent before attempting to remove the cerumen.8 Some recommend using the agents at home for up to a week before further removal attempts.8,9 Prolonged exposure to these agents can precipitate an otitis externa, allergic reactions, or a contact dermatitis in the EAC. These agents must be removed and the canal thoroughly dried after their use.4,6
ASSESSMENT After cerumen has been removed, it is critical to reexamine the ear to confirm that the EAC, TM, and hearing are all normal.2,4 Remove all remaining water and softening agents to prevent an otitis externa.4,6
AFTERCARE
FIGURE 166-8. Suction removal of cerumen.
Many authors recommend prescribing several days of topical otic drops to prevent or treat subclinical otitis externa, which is frequently present in these patients. Often recommended are topical combinations of antibiotics and steroids in solution or suspensions. Commonly prescribed agents include otic quinolones, Corticosporin Otic, Otic Domeboro, Otobiotic, Pediotic suspension, and VoSol to name a few. Consult an Otolaryngologist for patients with injuries, hearing deficits, severe otitis externa, or in whom cerumen removal was unsuccessful. Otherwise, the patient
CHAPTER 167: Tympanocentesis
can receive follow-up with their Primary Care Physician in 48 to 72 hours. Instruct the patient in the proper application of ear drops. They should return to the Emergency Department if they develop ear pain, ear discharge, fever, decreased hearing, vertigo, headache, or a stiff neck. They should also be cautioned against future use of cotton swabs or other instruments in the EAC.
COMPLICATIONS Numerous complications can result from the removal of cerumen from the EAC.2,3,4,7,9,12,13,19,20 The complication rate for irrigation is 1 per 1000 cases.2,4,7 It is higher for all other techniques. Irrigation can push cerumen further into the EAC. Irrigation fluid must be body temperature or slightly warmer. Cold fluid can cause caloric stimulation resulting in vertigo, vomiting, bradycardia, or syncope. Middle ear debris can be forced through a preexisting or iatrogenic TM defect, resulting in an otitis media, ossicle damage, labyrinthitis, mastoiditis, loss of hearing and balance, or a central nervous system infection. Otitis externa can result from abrasions to the EAC or retained fluids. Butterfly tubing is less likely than an angiocatheter to damage the EAC or TM because of its more pliable nature, larger diameter, and curved tip. It is known that mechanical dental irrigation devices, even at low pressures, can rupture the TM. For this reason, they are not recommended for cerumen removal.3,4,12,20 Instrumentation and suction should be used with caution to prevent secondary injury. This includes lacerations or abrasions of the EAC, rupture of the TM, pushing foreign bodies further into the EAC, and disruption or removal of the ossicles. Abrasions or lacerations to the EAC can result in an otitis externa. Cerumen softening agents can cause a contact dermatitis in the EAC, which may lead to an otitis externa. If the TM is not intact, these agents may cause permanent middle ear damage. Do not use these agents if the TM is ruptured acutely or the history suggests a potential defect.
SUMMARY Successful cerumen removal will often require using multiple techniques in sequence, adapted to the individual patient’s situation. With adequate anesthesia, careful planning of the procedural sequence, and gentle handling, those who have been relieved of cerumen impaction will be among your most grateful patients.
167
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Tympanocentesis Paul J. Jones
INTRODUCTION Tympanocentesis, first described in 1768, is a diagnostic and therapeutic procedure in which a needle is inserted through the tympanic membrane to aspirate fluid from the middle ear space (Figure 167-1). The procedure is considered diagnostic when the material obtained is sent for laboratory and/or microbiological analysis. It is considered therapeutic in most instances because it relieves pressure, thereby reducing pain and many times shortens the course of an acute otitis media (AOM). The procedure is quick, simple, and not as frequently performed as it should be. In the preantibiotic era, general practitioners and pediatricians would frequently perform the procedure for the relief of pain. Tympanocentesis is making a resurgence. It should be considered when a patient presents to the Emergency Department seeking treatment for a painful AOM. The American Academy of Family Physicians, American Academy of Pediatrics, and the Centers for Disease Control all include tympanocentesis in their practice guidelines for AOM. Many authors are calling for culturedirected antibiotic therapy for otitis media to reduce the need for broad-spectrum antibiotics and prevent, as much as possible, the emergence of multiresistant organisms.1–6
ANATOMY AND PATHOPHYSIOLOGY The ear is divided into the external, middle, and inner parts. The external ear is comprised of the auricle, the external auditory canal, and the external auditory meatus. The middle ear contains an air space and mastoid cells ventilated by the eustachian tube, the tympanic membrane, and the three ossicles. The inner ear is comprised of the cochlea, semicircular canals, fluids, and cranial verve VIII. The facial nerve courses through the middle ear space and mastoid process. It can be affected by a severe infection in these areas. Facial asymmetry during an acute ear infection is an indication of an unusually severe infection. Inspection of the tympanic membrane will usually show it to be bulging during an acute infection with loss of mobility on
FIGURE 167-1. Tympanocentesis of the right ear. The patient is lying supine with their head directed to the left. A. An ear speculum is inserted into the external auditory canal. A needle is inserted through the posterior inferior quadrant of the tympanic membrane to aspirate middle ear fluid. B. Magnified view of the tympanic membrane.
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pneumatic otoscopy. Conditions that are more chronic may show color changes of the tympanic membrane, with or without associated scarring and distortion.
INDICATIONS Tympanocentesis is performed to obtain fluid for microbiological culture and antibiotic sensitivity testing to determine the infectious cause of a middle ear effusion. Tympanocentesis is warranted for patients with AOM that is severe, unresponsive to 48 to 72 hours of conventional antimicrobial therapy, or in a child less than 8 weeks of age to rule out gram-negative organisms. Tympanocentesis is warranted for patients with an AOM and either an acquired or congenital immunodeficiency as they will often require directed therapy. Patients who develop AOM while taking appropriate antimicrobial therapy should undergo tympanocentesis to be evaluated for the organism responsible and its sensitivity to antibiotics. Tympanocentesis is also performed when the patient has an AOM associated with unusually severe pain, signs of toxicity, or bullous myringitis. Tympanocentesis will provide immediate relief of pain, pressure, and/or hearing loss associated with AOM or a middle ear effusion. It may be performed in a patient with AOM and multiple antibiotic allergies to determine appropriate antibiotic selection and sensitivity. Finally, it can be performed in the patient with AOM prior to the 48 hour “watchful waiting” period to allow accurate antibiotic selection if the patient is still symptomatic after 48 hours.
CONTRAINDICATIONS There are no absolute contraindications to tympanocentesis. It should not be performed in a patient who is uncooperative and cannot be restrained and/or sedated, as secondary injury may result. Uncooperative patients will require sedation to perform this procedure. Tympanocentesis should be performed by an Otolaryngologist if the landmarks on the tympanic membrane are unable to be absolutely identified or are obscured. Consult an Otolaryngologist prior to performing a tympanocentesis if an AOM is associated with a facial nerve palsy, mastoiditis, meningitis, encephalitis, brain abscess, or dural sinus thrombosis. Do not perform a tympanocentesis if the patient has an otitis externa.
EQUIPMENT • • • • • • • • • • • • • •
Topical otic anesthetic solution 21 gauge spinal needle, 2.5 or 3 inches long 3 mL aspirating syringe Ear speculum Ear wax curette Culture swabs and media Laboratory tubes for fluid cell count and differential Intravenous extension tubing Otoscope Headlamp or overhead surgical light source Frazier suction catheters Suction tubing Suction source CDT Speculum, optional
The Channel Directed Tympanocentesis or CDT Speculum (Walls Precision Instruments LLC, Baker City, OR) is a single
FIGURE 167-2. The CDT Speculum attached to an otoscope. (Photo courtesy of Walls Precision Instruments LLC.)
patient use, disposable, easy to use, and sterile device with built-in safety features. It was designed for use by Primary Care Physicians in the outpatient setting. The CDT Speculum attaches to most commonly available otoscopes (Figure 167-2). The device allows tympanocentesis and the aspiration of middle ear effusions. There are several advantages to this device over the traditional spinal needle on a syringe. The ensheathed needle protects the Emergency Physician as well as the patient from accidental needle sticks. The needle is incorporated into a speculum to prevent it from contacting the external auditory canal. The needle is automatically retracted by a spring into a protected position when not being used. A safety latch prevents accidental needle extension. Needle extension is limited and prevents it from being inserted too far into the middle ear cavity.
PATIENT PREPARATION Explain the risks, benefits, and potential complications of the procedure to the patient and/or their representative. The postprocedural care should also be discussed. Obtain a signed consent for the procedure. Place the patient supine on a locked gurney. View the tympanic membrane with an otoscope. Remove any cerumen from the external auditory canal using a curette. The cerumen may also be flushed from the external auditory canal. Refer to Chapter 166 for the complete details regarding cerumen removal. Again, view the tympanic membrane with an otoscope. Administer analgesic medicine in advance of the procedure. Topical anesthetic solutions include benzocaine–antipyrine (e.g., Auralgan), viscous 4% lidocaine, 8% tetracaine, and cocaine. The administration of topical or local anesthesia is often not helpful in the presence of an acute infection. Topical anesthetics can potentially affect culture results due to their antimicrobial activity. If culture results are not a concern, apply a topical anesthetic solution into the external auditory canal followed by a cotton ball. Allow the solution to remain for 5 to 10 minutes. Use a wick to absorb the topical anesthetic solution and dry the external auditory canal. Refer to Chapters 126 and 168 for the details regarding regional anesthesia of the ear. Children and uncooperative patients must be restrained and/ or sedated so that the head is immobile. A papoose is effective for young children. Some practitioners use intravenous sedation. Only rarely is procedural sedation or general anesthesia required.
CHAPTER 167: Tympanocentesis
TECHNIQUES TRADITIONAL NEEDLE-BASED TECHNIQUE Bend a 21 gauge spinal needle at the hub to approximately 60°. Attach the spinal needle to a 3 mL aspirating syringe. Insert the ear speculum into the external auditory canal (Figure 167-1A). View the tympanic membrane through the ear speculum using a headlight or overhead surgical light source for illumination or an operating otoscope. Insert the spinal needle through the speculum. Advance the needle and penetrate just into the inferior half of the tympanic membrane (Figures 167-1A & B). Avoid inserting the needle through the posterior superior quadrant of the tympanic membrane. This location is near the ossicles. Any movement of the needle near the ossicles could result in disarticulation of the ossicles requiring surgical repair. Aspirate the middle ear fluid into the syringe (Figure 167-1A). Simultaneously withdraw the syringe and ear speculum.
CHANNEL DIRECTED TYMPANOCENTESIS (CDT) SPECULUM Remove the sterile CDT Speculum from the package. Attach the aspirator bulb and tubing to the CDT Speculum. Attach the CDT Speculum to the otoscope. Align the arm of the CDT Speculum with the insufflator port of the side of the otoscope head. Firmly attach the CDT Speculum onto the otoscope. Rotate the CDT Speculum 90° clockwise so that the arm is aligned with the seam on the top of the otoscope head. Disengage the safety latch. Grasp the CDT Speculum with the dominant hand while simultaneously holding the otoscope and aspiration bulb with the nondominant hand (Figure 167-3). Compress the aspirator bulb. Insert the CDT Speculum into the external auditory canal. Visualize the tympanic membrane through the CDT Speculum. While looking through the CDT Speculum, press the actuator with the dominant thumb to extend the needle toward the inferior portion of the tympanic membrane (Figure 167-3). Continue to press the actuator to keep advancing the needle through the tympanic membrane and no more than 1 to 2 mm into the middle ear cavity. Release the compression on the aspirator bulb to aspirate the middle ear fluid. Release the pressure on the actuator to retract the needle. Withdraw the CDT Speculum from the external auditory canal.
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Place the tip of the CDT Speculum over the culture swab or medium. Compress the aspirator bulb to expel the middle ear fluid sample. Discard the CDT Speculum.
ALTERNATIVE TECHNIQUE An alternative method involves attaching intravenous extension tubing between the spinal needle and the syringe. The Emergency Physician can observe the tympanic membrane, insert the spinal needle, leaving a hand available for manipulation of the ear speculum or a suction catheter. An assistant is required to hold the syringe and aspirate the middle ear fluid. The remainder of the technique is as described previously.
ASSESSMENT Tympanocentesis will decompress the middle ear pressure and provide the patient significant symptom relief. Transfer the fluid into appropriate laboratory medium and containers as quickly as possible. Label the containers and have them transported to the laboratory for a Gram’s stain, culture and sensitivities, cell count, and differential of the cells present.
AFTERCARE Since most of the distress associated with the procedure in small children is due to immobilization, immediately release the child from the papoose or restraining device. Most patients will have immediate improvement in their pain and, in many cases, their hearing. Some Otolaryngologists will rinse the external auditory canal after a tympanocentesis with a 3% peroxide solution then absorb the solution with a wick. This is optional and at the discretion of the treating Emergency Physician. Because there is a small opening in the tympanic membrane, further drainage including bleeding may occur and should be expected for 48 to 72 hours. Instruct the patient and/or their caregivers to keep the ear dry for 2 to 3 days. This is especially true during bathing or hair washing. A cotton earplug coated with a thin film of petrolatum jelly (e.g., Vaseline) works well. The tympanic membrane usually spontaneously heals within 48 to 72 hours, but can take up to 10 days. Follow-up for laboratory results and documentation of antimicrobial change or appropriateness is necessary in 48 to 72 hours.
COMPLICATIONS Complications are uncommon. The most frequently cited complications include laceration of the ear canal, persistent perforation with or without otorrhea, development of a scar on the tympanic membrane, and an otitis externa. Pain and bleeding are usually minimal and self-limited. One of the most significant (but rare) complications is the disruption of the ossicles of the middle ear. Disruption of the ossicles can be avoided by inserting the needles into the inferior half of the tympanic membrane and preventing patient movement during the procedure. Injury to the chorda tympani, facial nerve, or internal carotid artery is theoretically possible, but virtually unheard of with this procedure.
SUMMARY
FIGURE 167-3. Proper grasping of the CDT Speculum attached to an otoscope. Note that the dominant thumb is placed on the actuator. (Photo courtesy of Walls Precision Instruments LLC.)
Acute otitis media is a common infection of childhood, but is also seen in adults. Most episodes respond quickly, with or without antimicrobial therapy. Tympanocentesis can be used to direct antimicrobial therapy in patients when a clinical response is delayed, host immunosuppression exists, or unusual organisms are suspected. Tympanocentesis can be used to provide immediate
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pain relief from a severe middle earache. The procedure is quick and simple to perform in the Emergency Department.
168
Auricular Hematoma Evacuation Eric F. Reichman
INTRODUCTION Blunt trauma to the auricle can cause abrasions, ecchymosis, hematoma formation, and lacerations. Abrasions and ecchymosis of the auricle require no therapy other than oral analgesics and observation for infection.1 Some authors recommend the application of topical antibiotics to all abrasions as prophylaxis for infection.2 Lacerations to the auricle are addressed in Chapter 96. This chapter addresses the management of an auricular hematoma. Injuries to the auricle are common due to its exposed position and lack of protection from surrounding structures.3 The most common cause for an auricular hematoma formation is blunt trauma while participating in the contact sports of wrestling or boxing.1,2,4–6 Such trauma may occur in other situations, including assaults, falls, fights, and motor vehicle crashes. Auricular trauma and hematomas are common in children due to the high incidence of head injuries during playtime.2,4 Blood dyscrasias may also cause an auricular hematoma. An auricular hematoma presents as a firm and painful swelling that obscures the normal convolutions on the lateral aspect of the auricle. It can develop within minutes to hours of the blunt trauma. An auricular hematoma must be evacuated to prevent the cosmetic disfigurement known as cauliflower ear. The sooner it is evacuated, the less chance of permanent disfigurement.4,5 After evacuation, the patient requires a pressure dressing to the auricle, oral antibiotics, and close follow-up to prevent complications.2,5,7,8
FIGURE 168-1. Cross section of the auricle. The skin on the medial surface has a layer of loose connective tissue that is lacking on the lateral surface.
of the perichondrium from the underlying cartilage. Auricular hematomas can be painful due to the rich sensory innervation to the area and the accumulation of blood in this relatively closed space.11 Failure to adequately evacuate a hematoma may lead to cartilage necrosis and a deformed ear. The necrosis is due to a combination of separating the cartilage from its blood supply and direct pressure effects from the hematoma. The cauliflower ear is a purely cosmetic deformity that results from an auricular hematoma not being evacuated and allowing the auricle to spontaneously heal. The hematoma is invaded by fibroblasts and slowly replaced by fibrous tissue. This organization of the hematoma causes irregular thickening of the auricle. The perichondrium, elevated from the cartilage by the hematoma, senses the
ANATOMY AND PATHOPHYSIOLOGY The auricle is that portion of the external ear that projects from the side of the head. It functions to augment sound delivery to the tympanic membrane and assist in sound localization. It is fixed in position by both ligaments and muscles.9 It has an underlying cartilaginous framework that is 0.5 to 1.0 mm thick and provides the auricle with its unique shape. The cartilage is a single, thin sheet of flexible yellow elastic cartilage with many convolutions on the lateral surface.10 The only portion of the auricle without cartilage is the lobule in which fibrofatty tissue replaces the cartilage.9 The cartilage is avascular and derives its blood supply and nutrients from the adjacent perichondrium.11 The skin covering the auricle is similar to that elsewhere on the body.12 It contains sebaceous glands and a varying number of hair follicles. The skin on the lateral surface of the auricle is tightly adherent to the perichondrium and lacks a subcutaneous layer (Figure 168-1). The skin on the medial surface of the auricle is loosely attached and has a layer of subcuticular tissue between the skin and perichondrium. Trauma may cause the perichondrium to be torn off the underlying cartilage due to the tight attachment of the skin to the perichondrium on the lateral surface of the auricle. This traumatic avulsion of the perichondrium causes hemorrhage into the space between it and the cartilage, allowing a hematoma to form (Figure 168-2). Bleeding into this potential subperichondral space causes dissection
FIGURE 168-2. An auricular hematoma. The blood collects between the perichondrium and the cartilage.
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FIGURE 168-3. The sensory innervation of the auricle. A. The distribution of cutaneous nerves surrounding the auricle. B. An enlarged view of the auricle demonstrating the cutaneous innervation.
lack of adjacent cartilage and activates chondroblasts. New cartilage is deposited on the surface of the hematoma causing further thickening and deformity of the auricle.
INNERVATION OF THE AURICLE A brief review of the innervation of the auricle will later aid in understanding the technique of regional anesthesia. Three nerves contribute to the sensory enervation of the auricle (Figure 168-3).8,11–15 The auriculotemporal branch of the mandibular division of the trigeminal nerve supplies sensation to the upper, lateral surface of the auricle. This nerve emerges subcutaneously just anterior to the auricle at the level of the external auditory canal. Two branches of the cervical plexus become subcutaneous at the posterior border of the midportion of the sternocleidomastoid muscle and ascend to the auricle. The lesser occipital nerve provides sensory innervation to the upper medial surface of the auricle. The great auricular nerve provides sensory innervation to most of the medial surface and the lower half of the lateral auricular surface.
INDICATIONS An auricular hematoma must be evacuated. The indication for evacuation is to prevent the cosmetic deformity known as the cauliflower ear.7 It is preferable to evacuate the hematoma within 12 to 24 hours after its occurrence. Although there is no urgency to immediately evacuate the hematoma, the longer it remains the higher the chance of clot organization and new cartilage deposition.7,16
CONTRAINDICATIONS There are no absolute contraindications to the evacuation of an auricular hematoma. If the skin overlying the hematoma is cellulitic, or if purulent material is drained from the hematoma, the patient will require hospital admission and intravenous antibiotics.1,8 An
Otolaryngologist or Plastic Surgeon should be immediately consulted on these patients. The auricular hematoma should be evacuated by a consultant if it has been present for more than 5 to 7 days. These hematomas have already begun organization and new cartilage has developed requiring curettage associated with the evacuation.7,16,21,23 An uncooperative patient (e.g., young child or due to altered mental status) may require evacuation under procedural sedation or in the operating room.
EQUIPMENT Auricular Anesthesia • Povidone iodine or chlorhexidine solution • 1 mL syringe • 10 mL syringe • 25 to 30 gauge needles, 2 inches long • 10 to 20 mL of local anesthetic solution without epinephrine Auricular Hematoma Aspiration • Povidone iodine or chlorhexidine solution • Tuberculin or insulin syringe • 0.25 mL of local anesthetic solution without epinephrine • 10 mL syringe • 18 gauge needle • Topical antibiotic ointment Auricular Hematoma Incision and Drainage • Auricular anesthesia as above • #15 surgical scalpel blade on a handle • Curved hemostat • Sterile drain (optional)
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10 mL syringe 18 gauge angiocatheter without the needle Sterile saline Topical antibiotic ointment Forceps
Mastoid Pressure Dressing • Petrolatum gauze • Cotton balls soaked in sterile saline • Dry cotton balls • 4 × 4 gauze squares • 4 inch elastic bandage • Scissors Surgical Pressure Dressing • Cotton bolsters or dental rolls • Needle driver • 4-0 monofilament nylon suture
PATIENT PREPARATION Explain the risks, benefits, and potential complications of the procedure to the patient and/or their representative. The postprocedural care should also be discussed. Obtain a signed consent for the procedure. Some Emergency Physicians omit the signed consent and place the following statement in the procedure note: “The risks, benefits, and complications were described and discussed with the patient. They understood this and gave verbal consent for the procedure.” This decision must be based on physician preference, hospital guidelines, and state guidelines for documentation requirements. Remove any dirt and debris from the auricle and surrounding skin. Apply povidone iodine or chlorhexidine solution to the same areas. Follow aseptic technique for the remainder of the procedure.4 In patients who are anxious and without other associated injuries, the administration of intramuscular, intravenous, or oral benzodiazepines may be beneficial.15
The methods of anesthesia for evacuation of an auricular hematoma range from none to a superficial skin wheal to a regional block. Some authors advocate using no anesthesia if needle aspiration of a small and fresh hematoma is performed.2 This is not generally recommended as the pain from an 18 gauge needle aspiration is more uncomfortable than local anesthesia infiltration. If using the aspiration technique to evacuate the hematoma, local anesthetic solution can be infiltrated directly over the hematoma. Apply a 25 to 30 gauge needle on a 1 mL syringe. Place a skin wheal, using 0.25 mL of local anesthetic solution without epinephrine, over the hematoma in the area of maximum fluctuance. When placing the skin wheal, be careful not to inject the local anesthetic solution into the hematoma. This will cause expansion of the hematoma and increase the separation of the perichondrium from the underlying cartilage.17 It may also cause new bleeding, which can increase the possibility of hematoma reaccumulation. A regional auricular block is the preferred method to obtain anesthesia.13 It prevents distortion of the auricle from direct injection and further separation of the perichondrium from the underlying auricular cartilage.17 Subcutaneous infiltration of the surrounding skin is less painful than injection directly into the sensitive auricular skin.15 The landmarks for regional anesthesia are simple to locate, consistent, and predictable. The greatest reason for failure of an auricular block is incorrect needle placement.14 A regional auricular block can be done prior to using the aspiration technique or the incision and drainage technique to evacuate the hematoma. If the aspiration technique fails (i.e., hematoma reaccumulates), then there is no need to reprep and perform an auricular block prior to performing the incision and drainage. There are three methods to perform a regional auricular block (Figures 168-4 & 168-5). Each method blocks the lesser occipital, great auricular, and auriculotemporal nerves. Some Emergency Physicians prefer to subcutaneously inject local anesthetic solution circumferentially around the attachment of the auricle to the head (Figure 168-4).2,11,13,17 An alternative method is based on blocking the sensory supply to the ear in a more anatomic distribution (Figure 168-5).8,14 This latter method uses half the anesthetic
AURICULAR ANESTHESIA The local anesthetic solution used for auricular anesthesia should contain no epinephrine.2,13,14,17 Epinephrine is not used for fear of intense vasoconstriction of end arterioles resulting in decreased perfusion with possible ischemia and necrosis of the auricle. Some authors recommend the use of 1/100,000 epinephrine mixed with the local anesthetic solution.1,15,16 The epinephrine may decrease bleeding by its vasoconstrictive action. It may also prevent reaccumulation of the hematoma after it has been evacuated. Authors who advocate using epinephrine state that the auricle has a rich blood supply and that, based on anecdotal evidence, there is no danger of ischemia or necrosis from the use of epinephrine in healthy patients without evidence of traumatized vascularity. Although many physicians will use epinephrine, it has not been proven safe to use or proven to prevent reaccumulation of the hematoma. It may be wiser to be conservative and not use epinephrine than to use it and have to deal with the complications to the patient and potential litigation. The choice of which local anesthetic to use is physiciandependent. Lidocaine (1%) is the most commonly used local anesthetic. Long-acting local anesthetic solutions, such as bupivacaine (Marcaine) or etidocaine (Duranest), may be used to provide analgesia for several hours after the procedure is completed.14
FIGURE 168-4. Regional anesthesia of the auricle. The technique of circumferential application of local anesthetic solution. Shaded areas represent subcutaneous infiltration of local anesthetic solution.
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FIGURE 168-5. Regional anesthesia of the auricle. A. A more anatomical auricular block. B. An alternative regional block that anesthetizes the auriculotemporal nerve at its origin. Local anesthetic solution is injected at the ⊗ symbol. Shaded areas represent subcutaneous infiltration of local anesthetic solution.
and half the number of subcutaneous injections than the former method. For these reasons, this author prefers the second method, which is described in the following paragraph. To perform a regional auricular block, first cleanse the auricle and surrounding skin of any dirt and debris. Apply povidone iodine or chlorhexidine solution. Place a skin wheal of local anesthetic solution 0.5 cm below the pinna of the auricle (Figure 168-5A). Insert a 2 inch, 25 or 27 gauge needle through the skin wheal, aimed just posterior to the attachment of the auricle to the head. Infiltrate subcutaneously, in a superior direction, always remaining 0.5 to 1.0 cm posterior to the auricular attachment to the head. Stop infiltrating at the level of the superior attachment of the auricle to the head. This infiltration requires 4 to 7 mL of local anesthetic solution. Withdraw the needle almost completely. Redirect the needle through the skin wheal and aimed just anterior to the attachment of the auricle to the head. Infiltrate subcutaneously, in a superior direction, always remaining 0.5 to 1.0 cm anterior to the auricular attachment to the head. Stop infiltrating at the level of the superior attachment of the auricle to the head. This infiltration also requires 4 to 7 mL of local anesthetic solution. Care must be taken not to inject too deeply anterior to the auricle as it can cause temporary paralysis of the facial nerve. An alternative to the anterior infiltration is the injection of 3 to 4 mL of local anesthetic solution just superior and anterior to the tragus (Figure 168-5B).1,18 This injection blocks the auriculotemporal nerve at its origin. Allow 10 to 15 minutes for the full anesthetic effect prior to beginning the procedure.17
Clean and prep the skin. Anesthesia is achieved by performing a regional auricular block or by placing a skin wheal of local anesthetic over the hematoma. Attach an 18 gauge needle onto a 10 mL syringe. Insert the needle into the area of maximum fluctuance (Figure 168-6). Apply negative pressure to the syringe, by withdrawing the plunger, to evacuate the hematoma. Express or “milk” the hematoma between the thumb and index finger of the nondominant hand while applying negative pressure with the syringe to ensure complete evacuation of the hematoma (Figure 168-6). Remove the needle and apply manual pressure to the area of the former hematoma for 3 to 5 minutes. If the hematoma recurs or if complete aspiration is not possible, perform the incision and drainage technique. If the hematoma is completely evacuated and does not recur, apply topical antibiotic ointment and a pressure dressing. There are several disadvantages to this technique. First, the hematoma frequently recurs.1,3,6,19 This means that the patient often needs a second drainage procedure. Even if the hematoma is adequately evacuated, the elimination of the dead space is problematic.19 The dead space may fill with blood or serous fluid requiring a second procedure. A surgically applied pressure dressing may alleviate the dead space and make the aspiration technique more successful. Finally, the aspiration technique may not remove all of the hematoma.1 Again, the patient will need a second procedure.
TECHNIQUES The methods for treating and managing an auricular hematoma require the evacuation of the hematoma and replacing the perichondrium onto the underlying cartilage. The techniques include aspiration, incision and drainage, and closed suction drainage. The first two techniques will be described in detail. The closed suction technique requires inpatient admission and is not a procedure to be performed in the Emergency Department. It will therefore not be described here.
ASPIRATION Some consider the aspiration technique to be the primary method to evacuate an auricular hematoma.2,3,5,6 They reserve the incision and drainage technique for incomplete aspiration or recurrence of the hematoma. Unfortunately, the hematoma frequently recurs after using the aspiration technique and the patient requires a second procedure to evacuate the hematoma.1,3,6,19 Because of the high rate of recurrence, this author and others prefer to use the incision and drainage technique as the primary procedure.16
FIGURE 168-6. The aspiration of an auricular hematoma. The hematoma is expressed with the thumb and index finger as negative pressure is applied to the syringe.
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FIGURE 168-7. Incision and drainage of an auricular hematoma. A. An incision is made along the helical rim. B. The hematoma is evacuated with the aid of a hemostat. The thumb and index finger express the hematoma from the subperichondral space. C. The subperichondral pocket is flushed with normal saline to remove any residual blood and clot.
For these above stated reasons, the aspiration technique is not the preferred method to drain an auricular hematoma.
INCISION AND DRAINAGE This is the preferred technique to evacuate an auricular hematoma.16 It requires a regional auricular block for anesthesia. This technique takes more time to perform than the aspiration technique. As noted previously, the skin should be cleaned and prepped in the usual manner. Perform a regional auricular block to provide adequate analgesia. Allow the block 10 to 15 minutes to achieve maximal effect.17 Incise the auricular skin with a #15 surgical scalpel blade at the edge of the hematoma (Figure 168-7A). When making the incision, it should follow the curvature of the pinna and be no longer than 1 cm. Gently peel this skin and attached perichondrium off the hematoma using forceps. Express or “milk” the hematoma with the thumb and index finger of the nondominant hand. Insert a curved hemostat and gently loosen any remaining blood clot (Figure 168-7B). Fill a 10 mL syringe with sterile saline and attach a plastic 18 gauge angiocatheter. Gently flush out the area of the hematoma (Figure 168-7C). Reapproximate the skin and perichondrium on the cartilage. Compress the tissue to eliminate any fluid and dead space. Some authors apply a small rubber drain through the incision to prevent accumulation of blood or serous fluid.4,8 The use of a drain is
optional. A drain can be made by cutting a small strip from a sterile Penrose drain. Apply manual pressure to the area of the former hematoma for 3 to 5 minutes. If the hematoma or serous fluid does not reaccumulate, apply topical antibiotic ointment and a pressure dressing as described below. If the hematoma or serous fluid does reaccumulate, consider inserting a rubber drain or applying a surgical pressure dressing.
PRESSURE DRESSINGS A pressure dressing must be applied to the auricle after the successful drainage of an auricular hematoma. It prevents reaccumulation of the hematoma or serous fluid, and supports the auricle while the perichondrium reattaches to the cartilage.3,6,10 The pressure dressing must be applied for at least 48 hours.4 The pressure dressing can be the traditional mastoid dressing or a surgically applied dressing.16,17,19,20 These pressure dressings apply even pressure over the entire auricle without compromising the blood flow while simultaneously eliminating the dead space within the wound.17
MASTOID PRESSURE DRESSING The most commonly applied dressing is the mastoid pressure dressing (Figure 168-8). Although simple to place, it has many
FIGURE 168-8. The traditional mastoid dressing. The convolutions are covered with a layer of petrolatum gauze. A. Saline-soaked cotton balls are packed over the convolutions, level with the helical rim. B. Trimmed gauze squares are placed between the auricle and the head. C. Fluffed gauze is placed over the auricle. D. The circumferential application of an elastic gauze bandage to the head. The bandage should cover the injured auricle and not the contralateral auricle.
CHAPTER 168: Auricular Hematoma Evacuation
disadvantages when compared to the surgically applied pressure dressing. It is bulky and hard to keep in place. It is very conspicuous. Patients must keep it dry and remain relatively inactive to prevent it from coming off. Place a piece of sterile dry cotton in the external auditory canal and level with the base of the auricular cartilage. Mold a sterile material that conforms easily onto all the convolutions of the auricle until it is level with the lateral helical rim (Figure 168-8A). The choices of material include cotton balls soaked in mineral oil, cotton balls soaked in saline, or petrolatum gauze. The material chosen is left to Emergency Physician preference and what is available in the Emergency Department. This author prefers to use petrolatum gauze. The petrolatum gauze allows the dressing to be removed with minimal trauma to the ear. Pack the auricle with saline-soaked cotton balls. All the convolutions of the auricle must be thoroughly packed. The packing of the auricular convolutions assures even application of pressure to all portions of the auricle. Cut out and discard a semicircle or a V-shaped section from a pile of gauze squares. Place the remaining C-shaped gauze pads behind the auricle (Figure 168-8B). The gauze pads should be built up until they completely fill the area between the auricle and the head. This padding is used to support the auricle as well as prevent undue contortion or uneven pressure from the compression dressing.2 Unfold and fluff several gauze squares or open a roll of gauze. Place the fluffed gauze over the lateral surface of the auricle (Figure 168-8C). Wrap an elastic bandage snugly over the auricle and around the head to hold the dressing in place (Figure 168-8D). The circumferential head dressing should not encompass the opposite auricle. The elastic bandage is used to compress the auricle between the two layers of gauze padding.
SURGICAL PRESSURE DRESSING A surgically applied pressure dressing may be used instead of the traditional mastoid dressing (Figure 168-9).1,7,16,19 This dressing applies even pressure over the former hematoma site to prevent reaccumulation. It takes more skill to apply than the traditional mastoid dressing. Aseptic technique is mandatory to prevent infection and perichondritis. This dressing requires a skin prep of a much wider area to include the entire medial and lateral surface of the ear, and the surrounding skin.
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The surgically applied pressure dressing has many advantages over the traditional mastoid dressing. It produces pressure exactly where it is needed. The wound is not obscured with a bulky dressing. This allows the patient to easily observe and monitor the site for reaccumulation of fluid and possible infection. This dressing is comfortable and well tolerated by the patient. It is unlike the bulky and conspicuous mastoid dressing that is difficult to keep in place, especially when sleeping. The dressing can remain in place while monitoring the auricle, unlike the mastoid dressing that must be removed and replaced daily. The patient can remain active, including taking a shower, without fear of the dressing coming undone. The surgical pressure dressing is adaptable to any location or a variety of hematomas. Trim a cotton dental bolster or cotton roll to fit the convolution of the auricle over the site of the drained hematoma. Place the cotton roll over the site of the former hematoma (Figure 168-9A). Place a second dental roll on the medial surface of the auricle opposite the first dental roll (Figures 168-9A & B). Place the needle of a 4-0 monofilament nylon suture immediately adjacent to the first cotton bolster. Pass the suture through the entire thickness of the auricle and out the medial surface. Pass the needle over the second cotton bolster and back through the auricle. Snugly tie the suture over the anterior cotton bolster (Figure 168-9B). The suture should be snug enough to allow the cotton bolsters to firmly hold the perichondrium to the cartilage without causing vascular compromise. Apply additional sutures using the same technique until the cotton bolsters are firmly attached and any dead space is eliminated. Depending upon the location of the hematoma, it may require a minimum of two to a maximum of four bolsters to reapproximate the skin and perichondrium and to eliminate all of the dead space. Monofilament nylon is the preferred suture material for this procedure.7 It causes less tissue reaction than silk, cotton, gut, or absorbable sutures. It has less of a tendency to cut the ear tissues when tied over the cotton bolsters. Monofilament nylon is less likely to wick bacteria into the auricle and cause an infection than multifilament nylon. The suture may be safely left in place for up to 3 weeks without any complications.
ALTERNATIVE TECHNIQUES An alternative to packing the pinna with petrolatum gauze is to use either ENT silicone putty or dental impression material.22,25
FIGURE 168-9. A surgically applied pressure bandage. A. A cotton roll is applied to the lateral surface of the auricle, over the site of the evacuated hematoma. A second cotton roll is applied on the medial surface of the auricle directly beneath the first cotton roll. The cotton rolls are secured with 4-0 monofilament nylon suture. B. Cross-sectional illustration of the surgical pressure dressing. The position of the cotton rolls and suture is seen in relation to the incision site. Note that the perichondrium is apposed to the cartilage and the dead space is eliminated.
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Evacuate the hematoma as described previously. Mix the chosen material to form a uniform composite and activate it. Mold it to fill the pinna, wrapping over the pinna and filling the space between the medial surface of the ear and the head. The putty or impression material will solidify in a few minutes after mixing it and the application. Apply an elastic bandage as described previously. Unfortunately, ENT silicone putty and dental impression material is not often available in the Emergency Department. The placement of cotton bolsters is often cumbersome and difficult if the Emergency Physician has little experience with this technique. An alternative is to use thermoplastic splinting material.24 Trim a sheet of thermoplastic splinting material to form a lateral and medial splint of an appropriate size to conform to the lateral and medial surfaces of the ear, respectively. Place the splints in warm water to soften them. Apply the splints to the surfaces of the ear, mold them to the contours of the ear, and apply pressure until they cool and become rigid again. Suture the rigid splints through the ear as described previously. A second surgical alternative to the use of bolsters is to apply running mattress sutures through the ear to reapproximate the skin and perichondrium.26–28 Begin posteriorly and weave 4-0 Vicryl or chromic gut suture through-and-through the ear in a running pattern to reapproximate the soft tissues and repair the ear contours. The main advantages of this technique include eliminating bolsters, eliminating the bulky dressing, and the comparable success rates while minimizing the reaccumulation of blood or fluid.
AFTERCARE The postprocedural care of the auricle is as important as the initial hematoma evacuation. Proper follow-up and care can minimize or prevent any cosmetic deformities. All patients should be seen within 12 to 24 hours to reevaluate the auricle for infection or reaccumulation of the hematoma or serous fluid. Analgesia can be provided by the use of nonsteroidal anti-inflammatory agents. Determine the patient’s tetanus immune status and provide prophylaxis as required. Provide all patients with oral and written instructions regarding the signs and symptoms of cellulitis and perichondritis. This includes the immediate return to the Emergency Department for increasing pain, progressive swelling, redness, tenderness, and warmth. Prophylaxis with oral antibiotics is indicated with any laceration, incision, or puncture of the auricular skin.4 Prescribe antibiotics for 5 days.4,5,16 Recommendations include a range of firstgeneration cephalosporins, antistaphylococcal antibiotics, or antipseudomonal antibiotics.4,5,16 Apply the pressure dressing for a minimum of 48 hours.4 A pressure dressing is recommended for a total of 4 to 5 days. A mastoid dressing must be removed daily to evaluate the auricle, then reapplied. A surgically applied dressing will avoid daily visits to the physician. Drain any residual clot or serous fluid at the follow-up visit. This can easily be accomplished by needle aspiration and replacement of the pressure dressing.6,20 If necessary, a sterile drain can be inserted.8 All drains must be removed within 48 hours of placement to decrease the risk of infection.
COMPLICATIONS The complications are primarily related to incomplete evacuation of the hematoma or reaccumulation of the hematoma. Incomplete evacuation of the hematoma, if by the aspiration technique, requires an incision and drainage of the hematoma. If necessary, gentle
curettage of the cartilage with a hemostat should dislodge the clot. Reaccumulation of the hematoma, or serous fluid, must be evacuated. Consider placing a sterile drain into the incision.8 Another option is to place a surgical pressure dressing.7 A hematoma located within the cartilage will result in a treatment failure and require operative management.29 Infection may complicate any surgical procedure. This may be due to reaccumulation or incomplete evacuation of the hematoma, which then becomes infected. Strict adherence to aseptic technique will usually prevent infection. Since patients are prophylactically placed on antibiotics, any cellulitis of the auricle at the follow-up visits requires hospital admission and intravenous antibiotics. Perichondritis is the most feared complication. It is an aggressive and rapidly progressive infection. The auricle will become red, hot, and exquisitely tender if perichondritis develops. This is followed by diffuse swelling and abscess formation. This infection can lead to significant cartilage necrosis and a deformed ear if not promptly treated. Pseudomonas aeruginosa is isolated in 95% of patients with perichondritis.1 Over 50% of cases are polymicrobial with Staphylococcus aureus associated with P. aeruginosa. These patients require Otolaryngology or Plastic Surgery consults for surgical debridement, broad spectrum intravenous antibiotics, and hospital admission.1,8
SUMMARY An auricular hematoma forms in minutes to hours after blunt trauma to the ear. It presents as a firm and painful swelling that obscures the normal convolutions on the lateral aspect of the auricle. It requires drainage to restore the normal convolutions of the auricle and prevent future deformity. Complete evacuation can be accomplished by needle aspiration or by incision and drainage. After the procedure, prescribe oral antibiotics prophylactically to prevent infection. Follow-up is required within 12 to 24 hours of the procedure to evaluate the patient for reaccumulation of the hematoma and infection. Patients should be educated about the signs and symptoms of perichondritis. Frequent wound evaluation is required until the auricle is healed.
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Nasal Foreign Body Removal Raemma Paredes Luck
INTRODUCTION Nasal foreign bodies are commonly seen in children, particularly those between 1 and 4 years of age. Adult patients with mental retardation or psychiatric illness can also present to the Emergency Department with a nasal foreign body. Young children are naturally curious and spend a great deal of time investigating themselves and the world around them. This involves handling, tasting, and smelling whatever they get their hands on. When these investigations go too far, the Emergency Physician is faced with a foreign body in a youngster’s nose. The most common foreign bodies found are beads, food (e.g., corn, nuts, peas, and popcorn), paper, rocks, and toy parts.1,2 Nasal foreign bodies also result from attempts to clean the nose and to control bleeding. In these cases, most of the foreign bodies retrieved consist of cotton swabs, paper, or sponge material.
CHAPTER 169: Nasal Foreign Body Removal
Children may present with a known nasal foreign body. However, other presentations are common and may be subtle. This includes body odor, halitosis, persistent unilateral nasal discharge, or recurrent epistaxis. Foreign bodies can be found during a routine examination or as an incidental finding on radiographs in the asymptomatic child.1,3,4 The task of the Emergency Physician in these cases is fourfold. First is to suspect the presence of a nasal foreign body. Second is to perform a thorough physical examination, including a search for the foreign body. Next is to visualize the foreign body. Finally, remove the foreign body efficiently and with minimal trauma.
ANATOMY AND PATHOPHYSIOLOGY The nasal cavity consists of two passages on either side of the nasal septum. The superior, middle, and inferior bony turbinates project medially into each passage and are covered by a mucous membrane overlying a venous plexus. Although foreign bodies can be located anywhere in the nose, most foreign bodies are found on the floor of the inferior turbinate or anterior to the middle turbinate.5 The cartilaginous septum is covered by a thin mucosa and receives its blood supply from the mucoperichondrium. Sensory nerves of the nasal cavity are branches of the greater palatine nerve and sphenopalatine ganglion.6 These nerves are easily anesthetized with topical anesthetics. The nasal cavity is separated from the orbit by the thin lamina papyracea and from the anterior cranial fossa by the cribriform plate of the ethmoid bone. A foreign body in the nasal cavity sets off an inflammatory response and the venous plexus becomes congested. This swelling may eventually obscure the foreign body from view. The longer the foreign body remains in the nasal cavity, the more likely the patient is to develop pressure necrosis, granulation tissue, infection, and a purulent discharge. The foreign body can erode into the surrounding areas over time if it is not removed. A unilateral malodorous discharge and/or epistaxis from a child’s nose is the hallmark of a foreign body. The presence of a disk or button battery in the nasal cavity requires urgent removal. These batteries contain a strong alkali, usually potassium hydroxide or sodium hydroxide. The moisture in the nasal cavity may cause corrosion of the battery, leakage of the battery contents, and a low-voltage direct current between the anode and cathode. This may cause liquefaction necrosis, tissue electrolysis, and tissue destruction (mucosa, cartilage, and bone) within hours.6 These patients need to be seen and followed by an Otolaryngologist after the battery is removed. An electrical thermal burn may cause damage to the nasal tissues that is more extensive than is visible initially in the Emergency Department.7,8 Patients may develop a delayed septal perforation and alar collapse from extensive tissue damage.9 Small magnets can produce pressure necrosis in the tissues, particularly when they span either side of the cartilaginous septum or a turbinate. These magnets are commonly used as beads, clasps for necklaces and bracelets, and in faux piercings.10,11
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CONTRAINDICATIONS There are a few contraindications to the removal of a nasal foreign body in the Emergency Department. One contraindication is if the airway is in danger. Do not attempt to retrieve a nasal foreign body if the patient is in distress or unstable. This might be due to a posteriorly placed foreign body or an uncooperative patient. Management of the airway in the Emergency Department or in the Operating Room must take priority to foreign body removal. An Otolaryngologist should be consulted in patients with nasal foreign bodies that are impacted, cause excessive bleeding, or have resulted in nasal perforation or penetration. Foreign bodies located posterior and superior to the middle turbinate pose a risk of being pushed back during retrieval and may perforate the cribriform plate. If a larger foreign body has entered the nose traumatically, it should be removed by an Otolaryngologist as it may have penetrated the cranial cavity, the orbit, or a sinus cavity.12,13 Other indications to consult an Otolaryngologist include failure of the Emergency Physician to remove the foreign body after repeated attempts, failure to properly sedate the patient, or the inability to sedate the patient. All of these contraindications may require foreign body removal in the Operating Room under more controlled circumstances and with equipment not available in the Emergency Department.
EQUIPMENT Nasal Anesthesia and Vasoconstriction • 1% or 2% lidocaine solution • 4% lidocaine solution with 0.25% phenylephrine • 4% cocaine • 0.25% phenylephrine (Neosynephrine) • 5 mL syringe or cotton pledgets • Atomizer device if available Manual Removal of Foreign Body (Figure 169-1) • Head light or head mirror, surgical lamp, or overhead light • Nasal speculum • Alligator forceps
INDICATIONS All nasal foreign bodies must be removed to prevent complications. The direct observation of a foreign body in one or both nostrils is an indication for its removal. The presence of signs or symptoms such as unilateral persistent nasal discharge, recurrent unilateral epistaxis, halitosis, or an unusual body odor should prompt a search for a nasal foreign body. More than 90% of nasal foreign bodies can be removed by the Emergency Physician with readily available equipment.1,3
FIGURE 169-1. Instruments used for the manual extraction of a nasal foreign body. Top row (from left to right): disposable medicine cup, pledgets, nasal decongestant spray. Bottom row (from left to right): zero-degree telescope, bayonet forceps, nasal speculum, 90° blunt-tipped ear pick or mastoid probe, small alligator (ear) forceps, and large alligator or Blakesley forceps.
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Hartman forceps Bayonet forceps Frazier suction catheter Ear curette Blunt mastoid hook Wire loop
Catheter Removal of a Foreign Body • Fogarty vascular catheter, size #4 or #5 • Foley catheter, 5 to 6 French • 5 mL syringe • Katz Oto-Rhino Extractor (InHealth Technologies, Carpinteria, CA) Positive Pressure • Cooperative parent • Bag-valve device • Face mask, various sizes • Male-male tube adapter Cyanoacrylate Glue • Cyanoacrylate tissue/wound glue or “superglue” • Paper clip or cotton-tipped applicator • Superglue removal equipment (Chapter 165)
decongestion of the nasal mucosa. If lidocaine is used, a vasoconstrictive agent such as epinephrine or phenylephrine should be added. A syringe can be used as a dropper to apply the medication intranasally. This is best done by administering several drops at a time and then reassessing visibility before adding more. If the entire dose is added at one time, the child is more apt to blow the medication out their nose before it can take effect. An atomizer device may also be used. Commonly available are devices that attach to a syringe (e.g., Mucosal Atomizer Device, Wolfe-Tory Medical Inc., Salt Lake City, UT) or a nasal decongestant container. Allow 5 to 10 minutes for the medication to take effect. If the patient is cooperative, it would be appropriate to have them attempt to blow the foreign body out of their nostril. Have the patient sit up and lean forward. Have the patient blow forcefully through their nose while covering the uninvolved nostril with a finger. Even if this has failed at home, it may work with the nasal mucosa swelling alleviated by the decongestants.9 Most children will need to be restrained while the foreign body is being removed. Even the child who appears cooperative and is adequately anesthetized may move suddenly while instruments are in the nasal cavity. One method is for the child to sit on their parent’s lap (Figure 169-2). The adult should cross their legs over the child’s
Nasal Wash • Bulb syringe • Normal saline Pediatric Immobilization • Sheets • Commercial immobilization device (e.g., Papoose board)
PATIENT PREPARATION Discuss the risks, benefits, complications, and different techniques available with the patient and/or their representative. Include the possibility of using procedural sedation initially or if initial attempts at removal are unsuccessful. Obtain consent for the removal procedure and the procedural sedation. The type, shape, size, and location of the foreign body are important factors to consider in choosing the most appropriate technique. The patient’s age, ability to cooperate during the examination and removal, and the experience and skill of the Emergency Physician can influence the choice of techniques. The Emergency Physician should observe universal precautions, especially eye protection, while working in close proximity to the mucous secretions in the airway. It is recommended to wear a gown, gloves, and a face mask with an eye shield or goggles. Both nasal cavities should be carefully inspected for foreign bodies before and after the mucosa is decongested. A child will sometimes insert foreign bodies up both nostrils. A good light source is indispensable for examining the nasal cavity and removing the foreign body. Preparation is important to ensure that the first attempt at retrieval is successful. A variety of equipment should be readily available at the bedside in the event that additional attempts and techniques are required. A Frasier suction catheter should be available to clear the nasal passages of blood and/or mucous. A good light source, particularly a hands-free device (i.e., overhead light source or a head lamp) is important in directly visualizing the foreign body and facilitating its removal. Anesthesia of the nasal mucosa is obtained by the topical application of lidocaine (maximum 4 mg/kg) or cocaine (maximum 3 mg/kg). Cocaine has the added benefit of vasoconstriction and
FIGURE 169-2. Method to properly restrain a child.
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legs, using one arm to restrain the child’s arms and trunk and the other arm to hold the child’s forehead (Figure 169-2). Alternatively, instruct an assistant to hold the patient’s head while the parent controls the body and limbs. Another alternative is to wrap the child in a sheet or use a commercial restrain device (e.g., papoose board).9 Severely uncooperative patients may require sedation, procedural sedation, or general anesthesia prior to removal of the foreign body. Procedural sedation may be used to facilitate removal, especially in the uncooperative or fearful patient. In one study, approximately 21% of pediatric patients with nasal foreign bodies required procedural sedation.4 The nasal foreign body was successfully removed in 95% of these cases. Ketamine was the most commonly used agent.
TECHNIQUES
FIGURE 169-4. The EasiEar Metal Curette (Splash Medical Devices LLC, Atlanta, GA).
DIRECT INSTRUMENTATION OR MANUAL REMOVAL The most straightforward and common method is to remove the anteriorly located nasal foreign body under direct vision. Instrument removal should not be attempted if the foreign body is located posteriorly. The instruments most often used include alligator forceps, bayonet forceps, straight forceps, or mosquito forceps. Hooked probes, such as right angles or curved hooks, ear curettes, wire loops, or mastoid hooks can also be utilized. In the absence of these, a paper clip can be fashioned into a hook. A novel device is the Lighted Forceps for Foreign Body Removal (Bionix Medical Technologies, Toledo, OH). It is a single patient use and disposable device that contains a light source and acts like a forceps (Figure 169-3).
FIGURE 169-3. The Lighted Forceps for foreign body removal. (Photo courtesy of Bionix Medical Technologies, Toledo, OH.)
The EasiEar Disposable Comfort Curette (Splash Medical Devices LLC, Atlanta, GA) is an improvement to the standard disposable plastic curette (Figure 169-4). It is a stainless steel, single patient use, and disposable curette. The rounded wire head is smooth. It lacks the jagged and sharp plastic edges that are often found on molded plastic curettes. The EasiEar has no abrasive edges, seams, or surfaces to potentially abrade the nasal mucosa. This design may prevent abrasions, lacerations, and procedurerelated bleeding. The spring wire shaft provides some flexibility and enhanced maneuverability when compared to molded plastic curettes, making the foreign body removal process easier. The angled head and flexible shaft allow it to be manipulated within the nasal cavity to remove a foreign body. These instruments enable the Emergency Physician to grasp the foreign body directly or pull it out from behind. Anterior located foreign bodies are often easily removed with instrumentation. Forceps are better suited for soft and irregularly shaped foreign bodies (Figure 169-5).5,14 Curettes and hooks are more effective
FIGURE 169-5. Using forceps to remove a thumb tack lodged in the nostril.
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BALLOON CATHETER EXTRACTION
FIGURE 169-6. Removing a round, smooth foreign body from the nasal cavity. The curette, mastoid hook, or wire loop is passed through the nares and behind the foreign body. The hook is used to pull the foreign body out.
for hard and spherical foreign bodies.5,14 Relative contraindications to instrumentation include posterior located foreign bodies, friable foreign bodies, and smooth or round foreign bodies. Potential complications include posterior displacement of the foreign body leading to nasal obstruction or even aspiration, mucosal abrasions and lacerations, and epistaxis. Insert the nasal speculum to hold the nostril open. Adjust the headlight or head mirror to illuminate the nasal cavity. It cannot be overemphasized how crucial adequate light and visibility are to successfully remove the foreign body. Remove any mucus or blood with the Frazier suction catheter. Grasp an irregularly shaped foreign body with a type of forceps. Forceps may cause a round or smooth foreign body to slip farther posteriorly when the jaws close. In these cases, pass a curette, wire loop, or mastoid hook behind the foreign body and pull it out (Figure 169-6).9 If the foreign body is a bead and the opening is facing outward, the jaws of a small alligator forceps can be passed through the opening (Figure 169-7). Open the jaws when they are beyond the lumen of the bead and pull the bead from the nasal cavity.
Some Emergency Physicians prefer to use a catheter with a balloon to pull foreign bodies from the nasal cavity. This technique has a reported success rate of 90%, and is used most successfully for foreign bodies that are round, smooth, and cannot be grasped readily.15 A balloon catheter does not work if the foreign body fully obstructs the nasal passage. Authors describe using a variety of catheters. This includes a #4 to 8 Fogarty vascular catheter, a #6 Fogarty biliary catheter, and a 5 to 6 French Foley balloon catheter.3,9,16 Suction is relatively contraindicated if the foreign body is shaped so that the suction device cannot form a seal or if the foreign body is friable. Inflate the balloon to ensure it has no leaks. Deflate the balloon. Lubricate the catheter. Insert the catheter until the balloon is beyond the foreign body. The catheter may be placed either above or below the foreign body.9 Inflate the balloon with 2 to 3 mL of air. Gently pull the catheter. The balloon will push the foreign body out of the nostril. A balloon catheter can also be used to stabilize a foreign body from behind while it is removed with a forceps. The disadvantage to this method is that it is more traumatic and epistaxis is more common.2 If the catheter is not passed under direct vision or if it is too large to pass around the foreign body, the Emergency Physician risks pushing the foreign body posteriorly and impacting it, obstructing the nasal passage, or dislodging it into the airway.
KATZ EXTRACTOR The Katz Extractor Oto-Rhino Foreign Body Remover (InHealth Technologies, Carpinteria, CA) is a device designed to extract foreign bodies from the nasal and auditory passages (Figure 169-8). It is a disposable single-use device consisting of a balloon-tipped catheter attached to a syringe. Always test the device before using it. Push the plunger to inflate the balloon and inspect it for any air leaks. Release the plunger to deflate the balloon. Grasp the device with the dominant hand (Figure 169-9). Gently insert the catheter along the wall of the nasal activity until the balloon is just past the foreign body (Figure 169-9A). Inflate the balloon by depressing the plunger on the syringe (Figure 169-9B). Withdraw the catheter and foreign body from the nasal cavity while maintaining the balloon in the inflated state (Figure 169-9C). If the foreign body has a central hole (e.g., candy or bead), insert the catheter through the hole, rather than behind it, and inflate the balloon.
HOGNOSE OTOSCOPE TIP The Hognose (IQDr. Incorporated, Manitou Springs, CO) is a disposable, latex free, and single-use device that attaches to a standard otoscope (Figure 169-10). It comes in three sizes (3, 4, and 5 mm), each with a color-coded tip. The size represents the cup size at the
FIGURE 169-7. An alligator forceps is used to remove a bead or other foreign body with a hollow center.
FIGURE 169-8. The Katz Extractor. The balloon at the tip inflates and deflates by pushing and releasing the plunger, respectively. (Photo courtesy of InHealth Technologies, Carpinteria, CA.)
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FIGURE 169-9. The Katz Extractor removing a nasal foreign body. A. The device is inserted until the balloon is just past the foreign body. B. The balloon is inflated. C. The Katz Extractor is removed with the balloon inflated and the foreign body is removed.
tip of the device. The tip is soft, self-molding, and looks like the nose of a hog. It has an insufflation port and suction tubing attached to its side. The adapter on the suction tubing attaches to standard wall suction tubing. Attach the Hognose to the otoscope similar to attaching a disposable speculum to an otoscope. Turn on the otoscope light source. Attach the hognose tubing to suction tubing and a suction source. Turn the suction source on to low or medium. Grasp the otoscope with the dominant hand. Insert the Hognose into the nasal cavity while visualizing the foreign body through the otoscope head. When the tip of the Hognose is just next to the foreign body, place an index finger over the insufflation port to engage the suction at the device tip. Gently advance the otoscope until the tip of the Hognose is against and attached to the foreign body. If you suddenly see black through the otoscope, the soft tip has collapsed on itself. Remove the finger over the insufflation port and reapproach the object. While maintaining suction, withdraw the Hognose with the foreign body attached.
GATORNOSE OTOSCOPE TIP FIGURE 169-10. The Hognose otoscope tip attached to an otoscope. (Photo courtesy of IQDr. Incorporated, Manitou Springs, CO.)
The Gatornose (IQDr. Incorporated, Manitou Springs, CO) is a disposable, latex free, and single-use device that attaches to a standard
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the plastic tubing just enough to create a flange. Turn on the suction source. Place a hemostat onto the tubing to temporarily clamp the suction tubing. Gently advance the flange tip into the nasal cavity until it contacts the foreign body, taking care not to push it inward. Remove the hemostat from the tubing to activate the suction. Gently but quickly remove the tubing and attached foreign body from the nasal cavity.
POSITIVE PRESSURE
FIGURE 169-11. The Gatornose otoscope tip attached to an otoscope. Note the three types of jaws that are available to snap onto the base of the device. (Photo courtesy of IQDr. Incorporated, Manitou Springs, CO.)
otoscope (Figure 169-11). It twists onto an otoscope like a speculum. It comes with three different jaw types that attach to the body of the device. These jaws are small flat jaws, large flat jaws, and open loop jaws. A trigger on the body of the device controls jaw opening and closing. Attach the Gatornose to the otoscope similar to attaching a disposable speculum to an otoscope. Turn on the otoscope light source. Grasp the otoscope with your dominant hand. Insert the ring finger into the trigger. Pull the trigger to close the Gatornose jaws. Gently insert the Gatornose jaws just into the nasal cavity. Push the trigger to open the Gatornose jaws and be able to view through the otoscope. Gently advance the otoscope while visualizing the foreign body through the otoscope head. Position the jaws above and below or anterior and posterior to the foreign body. Pull the trigger to close the jaws onto the foreign body. Withdraw the otoscope with the foreign body in the jaws of the Gatornose.
SUCTION TECHNIQUE Frazier suction catheters are most useful with small or round foreign bodies. Otherwise, this technique will be unsuccessful or will push the object farther into the nasal cavity. This technique is best reserved for large, round foreign bodies where suction can be maintained between the device and the foreign body. Complications include trauma to the surrounding tissues and epistaxis.17 Attach the Frazier suction catheter to the suction tubing. Turn on the suction source to at least 100 mmHg. Gently insert the catheter into the nasal cavity. Place a thumb over the hole in the catheter handle to direct the suction through the tip of the catheter. Gently advance the suction catheter until the tip is in contact with the foreign body. Withdraw the Frazier suction catheter and foreign body from the nasal cavity. For impacted smooth, spherical objects, suction with plastic intravenous tubing can be used.18,19 Cut a short length of plastic intravenous tubing and attach one end to the suction source. Fashion the other end into a small flange shape using a heat source and any metal object with a rounded end, such as the tip of a hemostat or larger clamp. Heat the jaws of the hemostat and insert them into
This technique is best utilized for foreign bodies that are large, posteriorly located, or occlude the nasal passage. It involves the generation of positive pressure in the nasopharynx behind the foreign body to force it out of the nostril. There are several ways to generate positive pressure within the nasal cavity. One is to simply ask the patient to occlude the unaffected nostril, take a deep breath through their mouth, close their mouth, and then forcefully exhale the air out through the nostril with the foreign body while keeping their mouth closed. This technique is most successful in older children and adults who are cooperative and can coordinate the movements. The advantage to this technique, if it is successful, is that no instruments are placed into the nose. The disadvantage is that the foreign body becomes a flying body. Eye protection is advised. Other variants of this technique have been developed. The “big kiss,” also known as the “parent’s kiss” or “mouth-to-mouth” technique, involves asking the parent to blow into the child’s mouth.20 This is similar to rescue breaths during cardiopulmonary resuscitation (CPR). Explain the procedure to the child and the parent. Instruct the parent to open the child’s mouth with one hand and stabilize the chin while occluding the unaffected nostril with a finger from their other hand. Instruct the parent to open their mouth, take a big breath, and then place their mouth over the child’s open mouth. The child’s mouth must be completely covered by their parents and a good seal formed. Instruct the parent to deliver a sudden and forceful breath into the child’s mouth. This entire sequence of events should only take 3 to 4 seconds to complete. This maneuver causes the child’s glottis to close. If enough pressure is generated, the foreign body will be expelled from the affected nostril. This technique may be less traumatic to the child and involves no instrumentation or restraint.20 High success rates have been reported.21 However, this technique may be difficult for some parents to perform. A modified version of this technique involves using a drinking straw or small tube between the child’s mouth and parent’s mouths. The parent then gives a big puff of air through the straw while the child tries to make a tight seal between their mouth and the straw. This technique can also be performed by the Emergency Physician without placing their mouth on the child’s mouth. A bag-valve-mask device (i.e., the Ambu-bag) can also be used to blow the foreign body out the nostril.22 Choose a face mask that is small enough so that it only covers the patient’s open mouth. Cover the patient’s mouth tightly with the mask. Close the unobstructed nostril with a finger (Figure 169-12). Squeeze the bag to force air into the mouth, lungs, and out the nose.22 A variant of this method uses an anesthesia bag connected to high-flow oxygen (10 to 15 L/min). Cover the mouth with the mask, close the thumb hole, and allow the bag to expand and gradually increase the airway pressure. If this does not expel the foreign body, compress the bag.3 The “Beamsley Blaster” technique makes use of the positive pressure generated from the application of high flow (10 to 15 L/min) oxygen from tubing attached to an oxygen wall outlet.23 The other end of the tubing is attached to a male-male
CHAPTER 169: Nasal Foreign Body Removal
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The main disadvantages of this technique are potential bonding of the nasal mucosa and the time it takes for the glue to bond to the foreign body.
ALTERNATIVE TECHNIQUES NASAL WASH The nasal wash technique involves the introduction at high pressure normal saline through a bulb syringe into the unaffected nasal cavity. Place approximately 7 mL of normal saline into a bulb syringe. Insert the bulb syringe into the unaffected nostril. Advance it into the nostril until a seal is created. Forcefully squeeze the bulb syringe. The pressure generated is believed to expel the saline and the foreign body from the other nostril. The use of this technique carries a high risk of aspiration of saline and the foreign body, as well as concerns about reflux of the saline into the sinuses or eustachian tubes.26 This technique should not be used in patients with a button battery or organic matter in their nasal passages. The increased moisture will hasten corrosion of the battery and cause swelling of the organic matter, making additional attempts at removal more difficult. This technique should also not be used in young infants and those with airway or neurologic abnormalities. FIGURE 169-12. Bag-valve-mask method of removal. The child is restrained and the contralateral nostril is occluded. Bag-valve-mask is applied on the mouth to create a seal and a few breaths are delivered until foreign body is expelled.
adapter, which is then inserted into the unaffected nostril. The set-up generates enough pressure in the posterior nasopharynx to dislodge the foreign body from the nostril. The patient’s mouth must be closed during the procedure to create a seal. Although there were no complications noted in the initial study, a subsequent case of barotrauma (subcutaneous orbital emphysema) was recently reported.24 If an SMR cabinet or other blower with a nasal tip is available, place the nasal tip in the unobstructed nasal cavity. This method is contraindicated if there are foreign bodies in both nasal passages. It is important to be sure that the nasal tip is placed in the open nasal cavity or the foreign body could be blown into the trachea or esophagus. Blow short puffs of air during the child’s cries. The soft palate will close when the child is vocalizing and direct both the air and the foreign body out the other nostril.2
CYANOACRYLATE GLUE—ASSISTED REMOVAL Cyanoacrylate glue can be used to extract spherical and other solid foreign bodies that are visible.25 However, this technique can be fraught with complication. There is a chance of gluing the foreign body to the nasal mucosa as well as creating a glue foreign body. The foreign body can be further impacted if pushed posteriorly or fall into the oropharynx and aspirated. Obtain a long, thin object (e.g., straightened paper clip or the stick end of a cotton-tipped applicator). Moisten the tip of the paper clip or applicator stick with a very tiny amount of cyanoacrylate glue. A larger amount can drop off into the nasal cavity. Insert the paper clip or applicator stick before the glue dries and until it just touches the foreign body. Maintain this position for 30 to 60 seconds to allow bonding of the glue to the foreign body. Do not allow the drop of glue to fall from the stick, as it will bond to the nasal mucosa. Do not touch the tip of the wooden applicator stick to the nasal mucosa, as it will bond to the mucosa. Remove the paper clip or applicator stick with the foreign body attached.
MAGNET REMOVAL An occasional patient will present with a mini-magnet adhered to the nasal mucosa. The source of the magnets can be from their insertion in young children or nasal jewelry in older children, adolescents, and adults.10 Adherence of magnets across the nasal septum creates the potential for septal necrosis and perforation.11,27,28 They may be difficult to remove because of the attractive force they create across the nasal septum. Numerous methods can be used to facilitate magnet removal. They may be grasped with a variety of forceps or hemostats. A hook can be made from nonferromagnetic blunt probe.10 A magnet can be used to facilitate nasal magnet removal.11,29,30 A pacemaker magnet is readily available in most Emergency Departments. A small and strong pocket magnet may also be available from the hospital maintenance department.
ASSESSMENT Inspect the nasal cavity for any remaining fragments of the foreign body, ulcerations, bleeding, or a second foreign body. A gray precipitate may be noted if a disk battery has been removed. After a battery is removed, the nasal cavity should be irrigated with saline to remove any electrolyte solution or precipitate to prevent further damage.12 Bleeding can be controlled with topical phenylephrine or epinephrine, pressure, or any of the methods described to control epistaxis (Chapter 172).
AFTERCARE The patient can be discharged home with nasal saline spray to the affected nostril until secretions are clear of blood or pus. Oral antibiotics may be prescribed if the patient has developed sinusitis from a retained foreign body. Patients with ulcerations on opposing sides of the nasal cavity must be followed up to prevent obstructive synechiae or adhesions from forming. Patients with button batteries, mini-magnets in their nasal passages, or other injuries or complications should follow up with an Otolaryngologist. The caretakers should be educated to remove any small objects from the child’s reach, supervise children when they have access to small objects, and childproof the house.
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COMPLICATIONS Complications can arise from the nasal foreign body itself or the removal technique. Foreign bodies can cause nasal obstruction, epistaxis, pressure on surrounding tissues, infection, ulceration, perforation, or aspiration.5 The risk of complications increases the longer the foreign body is present. Otitis media, sinusitis, facial and orbital cellulitis, epiglottitis, and meningitis have been associated with retained nasal foreign bodies.5,8 The most significant complication would be to dislodge the foreign body into the airway. This is most likely to occur in an uncontrolled situation. Placing the patient supine and in the Trendelenburg position may prevent accidental aspiration of the foreign body.31 Consider the use of sedation, procedural sedation, or general anesthesia if the patient is uncooperative. Potential complications associated with each technique were described with each specific technique. Aspiration from posterior dislodgment of a nasal foreign body remains a serious potential complication for all the techniques described. Positive pressure techniques can result in barotrauma. Periorbital emphysema has been described in the “Beamsley Blaster” method.24 Secondary infection may also result from the procedure. In most cases, once the foreign body has been removed antibiotics are generally not indicated. Complications related to manipulation within the nasal cavity include bleeding or subsequent infection. In rare instances, an anterior nasal pack may be required to tamponade bleeding. Toxic doses of cocaine and/or lidocaine may result in cardiac arrhythmias and seizures.
SUMMARY The vast majority of nasal foreign bodies can be safely removed by the Emergency Physician with instruments that are readily available in the Emergency Department. There are multiple techniques for removing foreign bodies from the nasal cavity. Each has its own advantages and disadvantages. These methods include the use of forceps, balloon catheters, and positive pressure. The Emergency Physician should choose a method according to the shape and location of the foreign body, the tools available, the cooperativeness of the patient, and their experience with the different removal techniques.
170
Suspect a nasal fracture in the blunt trauma patient with a history of epistaxis, new onset nasal blockage, or a change in nasal appearance. Determine whether the patient has a prior history of a nasal bone fracture, as repeat nasal bone fractures will be more difficult to reduce. An old photograph of the patient may aid this determination. One study revealed that 30% of injured noses had a preexisting nasal deformity.7 At least 48% of the general population has a deviated nasal septum.8 Physical examination may demonstrate skin lacerations, nasal tenderness and mobility, internal mucoperichondrial tears, ecchymosis, or a septal hematoma. A septal hematoma must be drained to avoid cartilage necrosis and the subsequent saddle nose deformity. Refer to Chapter 171 regarding the complete details of managing a nasal septal hematoma.
ANATOMY AND PATHOPHYSIOLOGY The mechanism of injury, force of impact, direction of impact, and the history of any prior nasal deformity must be ascertained from the patient in order to understand the potential magnitude of the fracture. If possible, obtain photographic documentation before any attempts at nasal manipulation. The Waters and lateral nasal radiographs will often support the physical findings of a nasal fracture (Figure 170-1). Many Surgeons recommend radiographs as part of the medical legal documentation, although many do not agree. Plain radiographs can have a high false-negative rate due to the lack of fine resolution or a high false-positive rate from the misinterpretation of the normal bony sutures.9,10 A CT scan is more sensitive and specific to identify a nasal bone fracture. Unfortunately, its cost and the radiation exposure are significant. A nasal fracture can often be diagnosed based upon the history and the physical examination. Reserve the CT scan for those patients with suspected nasal fractures that may have additional injuries requiring a CT scan. The direction of the force to fracture the nasal bone is variable. There are several lateral and frontal force injury classifications, but no consensus exists.5,11,12 One study demonstrated that 66% of nasal fractures were due to lateral forces, 13% from frontal forces, and 21% from mixed forces.3 This predominance of lateral force fractures is due to several factors.13 It takes more than twice the force, in cadavers, to cause a frontal impact fracture than to cause a lateral impact fracture. Always rule out any associated maxillofacial injuries, especially when the patient presents with ocular hypertelorism and
Nasal Fracture Reduction Eric F. Reichman
INTRODUCTION Nasal fractures due to blunt trauma are a common occurrence. Fights, auto accidents, and sports accidents account for most fractures in an urban setting. Work, farm, sports, or leisure activity accidents account for most of these injuries in rural areas.1 The majority of nasal fractures occur in males aged 15 to 25 years old, with fights being the major etiology.2–5 Nasal fractures are often missed on initial evaluation, especially when there are many more urgent trauma concerns. It is best to perform closed or open reduction of a nasal fracture within the first 2 weeks, when it is easiest to avoid more elaborate operations later to correct the disfigurement and nasal airway obstruction. Perform the reduction in children within 3 to 7 days, as fracture fixation occurs faster than in adults.6
FIGURE 170-1. Radiograph demonstrating a Waters view of a deviated nasal septum and right nasal bone fracture.
CHAPTER 170: Nasal Fracture Reduction A
Frontal process of maxilla
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B Nasal bone
Nasofrontal angle
Bifid portion of septal cartilage Edge of piriform aperture Lateral crus of alar cartilage Sesamoid cartilages Dome of alar cartilages Medial crus
Nasolabial angle
FIGURE 170-2. Anatomy of the external nasal cartilages. A. Frontal view. B. Lateral view.
lid lateral-pull laxity.14 Thoroughly evaluate the patient for the presence of other head or neck injuries if they have a nasal fracture. Associated head and neck injuries take priority for management and evaluation as they can result in significant morbidity. Subcutaneous emphysema may be found in nasal trauma cases, as well as with simple lamina papyracea fractures, and nose blowing. Scleral chemosis, subconjunctival hemorrhage, eyelid edema, periorbital ecchymosis, or subconjunctival hemorrhage may all be associated with a complex facial fracture or an isolated nasal fracture. A history of anosmia indicates a possible cribriform plate fracture. Evaluate the patient for cerebrospinal fluid rhinorrhea and the presence of beta2-transferrin.1 Consider obtaining axial and coronal computed tomography scans of the paranasal sinuses with possible cisternography. The nose consists of the external nose and the septum. The external nose consists of the bony upper third, the cartilaginous lower third, and the surrounding soft tissue and skin (Figure 170-2). The bony part consists of the paired nasal bones, the frontal processes of the maxillary bones, and the nasal processes of the frontal
bones. The inferior nasal bones are thinner than the superior nasal bones. Thus, the lower bony portion is the most common area of the external nose to be fractured. The cartilaginous components consist of the arched paired upper lateral cartilages and the horseshoe-shaped paired lower lateral cartilages. The former articulates with the cartilaginous septum and nasal bones, while the latter has ligamentous attachments to each other in front of the cartilaginous septum. The lower and upper lateral cartilages articulate with each other and form a crucial part of the nasal valve, the critical control point of nasal resistance, and obstruction. Any of these relationships can become dislocated from a traumatic impact and will require repair for an optimal functional and aesthetic outcome. The more lateral sesamoid cartilages are relatively unimportant in these regards.15 The bony nasal septum consists of the perpendicular plate of the ethmoid bone, the vomer, the anterior nasal spine, the maxillary crest, and the palatine bone (Figure 170-3). The perpendicular plate of the ethmoid bone is thin, except at its articulation with the vomer and cartilaginous septum. The perpendicular plate of the
perpendicular plate of ethmoid bone Vomer Quadrangular cartilage Sphenoid sinus
Anterior nasal spine
Transverse palatine suture
Pterygoid hamulus
Vomeromaxillary suture (maxillary crest location) Palatine bone
Palatine process of maxilla
FIGURE 170-3. Anatomy of the nasal septum.
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FIGURE 170-6. An “open book” nasal fracture resulting from a frontal impact.
FIGURE 170-4. Schematic illustration of a common nasal septal fracture pattern. The fracture proceeds from the area of the maxillary crest, through the vomer, and up into the perpendicular plate of the ethmoid like a backward “C” going up into a “T”.
ethmoid bone is the most common location for a septal fracture. The quadrangular cartilage of the septum is anteriorly located on the maxillary crest. It can be dislocated into either nostril with a significant force, especially from an inferior direction, and result in nasal airway obstruction.5 The bony nasal septal fracture is often similar, regardless of whether the etiology is a frontal or lateral impact (Figure 170-4). It usually begins just posterior to the nasal spine, at or just above the maxillary crest. The fracture can progress through this area and straight into the vomer where it curves like a “C,” vertically upward and into the perpendicular plate of the ethmoid bone.16 Nasal fractures increase in severity from a unilateral depression without a septal fracture, to a nasal twist or deviation, to a significantly comminuted nasal fracture as the frontal or lateral force of impact increases (Figure 170-5). Between these extremes are the moderately severe bilateral fractures with the contralateral side being driven outward and more significantly impacted traumas, such as the previously described C-shaped septal fracture with overriding and interlocked fragments. This latter condition often appears as the classically shortened and twisted nose with tip ptosis from columellar retraction. There is often significant nasal airway obstruction as the quadrangular cartilage telescopes over the perpendicular plate of the ethmoid, causing thickening at this point and the appearance of a bilaterally deviated nasal septum.17
The more common lateral force shifts the bony pyramid laterally (Figure 170-5), while a frontal impact broadens the nose. “Open book fractures” may occur in pediatric patients due to the open, midline suture of the nasal bones. This results in each of the nasal bones being shifted laterally (Figure 170-6). Children have fewer nasal fractures because of their smaller and more cartilaginous (i.e., more elastic) noses.18,19 Greenstick fractures are more likely in children because of their resilient noses and can be present when it is not apparent externally.20,21
INDICATIONS Attempt to reduce nasal fractures within the first 3 hours after the trauma, before significant edema develops. Otherwise, perform the reduction 3 to 10 days after the injury when the edema subsides. The indications for a closed nasal reduction include unilateral or bilateral nasal bone fractures, with or without a nasal septal fracture. Interestingly, one study found that 30% of nasal fractures that underwent closed nasal reduction were still malaligned postoperatively.17 Strongly consider reduction under procedural sedation or general anesthesia for pediatric nasal fractures.
CONTRAINDICATIONS There are no absolute contraindications to nasal fracture reduction as long as the timing, the patient’s health status, and associated injuries are considered. The proper approach varies by the extensiveness of the fracture. Open nasal reduction is required for more severe nasal fractures, especially those with C-shaped septal fractures and cartilage telescoping over the perpendicular plate of the ethmoid bone.3 Some authors have defined the indications for this more aggressive approach as being a nasal pyramid deviation exceeding one-half of the width of the nasal bridge.17 Consider using an open approach, either during the same setting or within a few days, if deformities persist after closed reduction. Relative indications for the open approach include fracture-dislocations of the caudal septum, open septal fractures, septal hematomas, displaced fractures of the anterior nasal spine, associated alar cartilage deformities, or recent intranasal surgery. An open approach may be required if an extensive septal deformity exists.2 Otherwise, the nasal deformity will be difficult to reduce against the interlocked forces.2
EQUIPMENT
FIGURE 170-5. Nasal fractures resulting from lateral forces. A. Unilateral nasal fracture. B. Bilateral nasal fracture. The arrows depict the direction of the force of impact.
• • • • •
Headlight with light source, or overhead light 5 mL syringe 27 gauge needle, 1.5 inches long 25 gauge spinal needle Local anesthetic solution containing 1:100,000 epinephrine
CHAPTER 170: Nasal Fracture Reduction
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interpupillary line and extending downward to the base of the nasal columella. A point one-third of the way down from the cephalic end is the reference point for any deviation.22 Consider the administration of parenteral analgesics, sedatives, or procedural sedation. Refer to Chapter 129 regarding the details of procedural sedation and analgesia. Obtain a prereduction photograph of the patient’s face and nose, if possible.
NASAL ANESTHESIA Anesthetize the nasal mucosa. Insert a nasal speculum. Apply oxymetazoline nasal spray bilaterally to decongest the nasal mucosa. Place 4 mL of 4% cocaine onto cotton pledgets. Cocaine is a vasoconstrictor, a decongestant, and an anesthetic. Insert the nasal speculum and pack the cocaine-soaked pledgets into the nose using a bayonet forceps (Figures 170-8A, 9, & 10). Ideally, place four
A FIGURE 170-7. Nasal fracture reduction instruments. From left to right: an elevator, a Walsham forceps, and an Asch forceps (with rubber tubing on one tong).
• Oxymetazoline nasal spray • 4% cocaine, 4 mL • Other nasal decongestants and anesthetics (Chapter 172 and Table 172-1) • Surgical cotton paddies, 0.5 × 2 inches • Bayonet forceps • Walsham forceps (Figure 170-7) • Asch forceps (Figure 170-7) • Rubber tubing • Boies nasal fracture elevator (Figure 170-7) • Killian nasal speculum • Silastic nasal splints or Goldsmith splints • Antibiotic impregnated strip gauze or nasal tampon • Plaster of Paris splinting/casting material • 5-0 plain gut suture • Paper tape, 1 inch wide • Benzoin solution
PATIENT PREPARATION Explain the procedure, its risks, and benefits to the patient and/or their representative. Significant complications include patient dissatisfaction, the possible need for open reduction within 2 weeks, and formal nasal reconstruction months later. Other potential complications (all of much lower probability) include adverse reactions to the local anesthetics, excessive bleeding, infection, saddle nose deformity, septal perforation, CSF rhinorrhea, and/or visual disturbances. Almost all of these complications can result from the reduction procedure, but also from the nasal fracture without and reduction attempts. Obtain an informed consent for the procedure. Place the patient sitting upright in a multiposition procedure chair, or on a stretcher, with the head elevated to decrease blood flow and bleeding. Obtain an objective measure of the degree of lateral displacement. Draw a perpendicular line from the midpoint of the
FIGURE 170-8. Topical anesthesia of the nasal mucosa. A. Surgical cotton pledgets soaked with cocaine placed in the nares. B. Typical sites for placement of the pledgets: (1) nasal floor, (2) posterior aspect of middle and inferior turbinate, (3) intranasal dorsum, and (4) along the nasal septum.
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B Nasopalatine nerve
Olfactory nerves
Sphenopalatine ganglion
Anterior ethmoidal nerve
Greater palatine nerve
Middle palatine nerve
Lesser palatine nerve
FIGURE 170-9. Nerve supply of the nasal mucosa. A. The nasal septum. B. The lateral nasal wall.
pledgets in each nostril at the strategic points of the neurovascular supply (Figure 170-8B). These areas include the posterior edge of the middle turbinate (sphenopalatine ganglion and artery), the anterior to middle turbinate and opposing septum (anterior ethmoid nerve and artery), the nasal floor (branches of both nerves and arteries), and the midseptum (branches of both nerves and arteries).6,15 Allow the cocaine pledgets to remain in the nasal cavity for 10 minutes. Other anesthetics, decongestants, and anesthetic– decongestant combinations can be used depending upon availability. Refer to Chapter 172 for a more complete discussion of topical nasal anesthesia and decongestion. Inject local anesthetic solution to anesthetize the remainder of the nose. The most commonly used agent is 1% or 2% lidocaine containing 1:100,000 epinephrine.23 Acidosis from the injured tissues can make local anesthesia less effective. The addition of sodium
A
bicarbonate, at a 1:10 dilution, will counteract the acidosis and lessen the discomfort from the injection.24 Perform the local anesthetic injections intranasally to avoid the added pain of puncturing through the skin (Figures 170-11 & 12). Infiltrate subcutaneously to anesthetize the external, nasal, infratrochlear, and infraorbital branches of the trigeminal nerve.3,4 Insert the needle into the nasal cavity. Infiltrate along the nasal floor to anesthetize the superior alveolar nerve and ganglion. Infiltrate posterior to the inferior and middle turbinates to block the sphenopalatine nerve and ganglion. Allow 10 to 15 minutes for the local anesthetic agent to take effect. Assess the adequacy of the anesthesia using pinprick of the nasal mucosa. If intranasal injections are performed properly in a patient who is under procedural sedation and analgesia, the rare but potentially serious complications of using topical cocaine may be avoided. One
Posterior ethmoidal artery
Sphenopalatine artery
B Anterior ethmoidal artery
Greater palatine artery FIGURE 170-10. Blood supply of the nasal mucosa. A. The nasal septum. B. The lateral nasal wall.
Posterior ethmoidal artery Sphenopalatine artery
Nasal branch of greater palatine artery
CHAPTER 170: Nasal Fracture Reduction
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during outward reduction (Figure 170-14).6 Repeat the procedure on the contralateral side if there is a bilateral nasal bone fracture.
NASAL SEPTAL REDUCTION A nasal septal fracture is often present if bilateral pyramidal fractures exist. Always reduce the nasal bone fracture(s) before manipulating the septum. Insert a nasal speculum and determine whether the reduction of the nasal bones results in a straightening of the septum. If not, withdraw the nasal speculum and reduce the septum with the Asch or Walsham forceps (Figure 170-15). Insert the forceps with one blade in each nostril. Gently close the blades of the forceps to grasp the septum. Elevate the septum upward and anteriorly to disimpact any interlocked fragments. Reinsert the nasal speculum and visualize the nasal septum. Insert a Boies or Freer elevator under direct visualization and straighten the septum more precisely. FIGURE 170-11. Intranasal injection with speculum exposure and a fine needle.
paper proposed using EMLA (eutectic mixture of local anesthetics) cream externally and cocaine intranasally.25 This has yet to become a broadly accepted technique. The Emergency Physician may not feel comfortable with the technique of intranasal injection and the nerves may be anesthetized percutaneously as described in Chapter 126.
TECHNIQUES NASAL BONE REDUCTION Several studies have demonstrated that closed nasal reduction is 80% to 95% successful.8,26 Measure the distance from the nostril rim to the nasofrontal angle in order to avoid putting the blade in too far (Figure 170-13A). Insert one blade of the Asch forceps, one blade of the Walsham forceps, or a Boies nasal fracture elevator into the nostril to the measured distance. Place the instrument against the depressed nasal bone. Apply a gentle upward and outward force while simultaneously applying digital counterpressure to guide the bone into reduction (Figure 170-13B). Alternatively, cover the other blade of the Asch or Walsham forceps with rubber tubing so that it can provide counterpressure to the intranasal blade
ASSESSMENT Thoroughly evaluate the nasal cavity and nose. Determine the adequacy of the reduction procedure. Determine visually whether the nasal bones and the nasal septum are reduced. Consult an Otolaryngologist if the manipulations fail to provide a satisfactory reduction, if the fracture appears too comminuted, or if the nose or septum is too deviated for a closed approach. The patient may require open reduction 2 weeks from the day of the trauma. Perform a thorough examination to rule out an associated septal hematoma. This must be evacuated and managed to prevent complications. Refer to Chapter 171 regarding the details of managing a nasal septal hematoma. Attempt to suture any nasal septal mucosal tears that exist from the fracture or the reduction procedure using 5-0 plain gut suture. Warn the patient of the potential for a septal perforation that can lead to chronic crusting, bleeding, or an audible whistling. Obtain postreduction photographs of the nose, if possible. Place the prereduction and postreduction photographs in the patient’s medical record.
AFTERCARE Brace the septum for stability with bilateral Silastic splints for 5 to 10 days. This also helps to prevent the formation of a nasal septal hematoma. Doyle or Goldsmith septal splints have lumens that
FIGURE 170-12. Intranasal injection of local anesthetic solution: (1) the nasal spine, (2) the nasal tip, (3) the nasal dorsum along the outside of the nasal bones, and (4) the infraorbital nerve.
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FIGURE 170-13. Closed reduction of a nasal fracture. A. Measure the nostril to nasofrontal angle (N-NFA) distance with the Boies elevator or another instrument. B. Place the elevator or forceps intranasally, just less than the N-NFA distance, and elevate the depressed bone. Simultaneously reduce the contralateral nasal bone downward.
allow the patient to nasally breathe in the postoperative period. These splints must be kept open by the patient applying six drops of hydrogen peroxide to each nostril three times a day, while avoiding swallowing this solution. A simpler and more convenient alternative is bilateral anterior nasal packing. The equipment is readily available in every Emergency Department. This is especially useful in cases of epistaxis. Apply bilateral petrolatum impregnated gauze ribbon, iodinated gauze ribbon, nasal sponges/tampons, or balloon catheters. Avoid overpacking the nasal cavity as this can splay out the fractured nasal bones.6 All patients with nasal packing must be placed on oral antibiotics with gram-positive and gram-negative coverage, such as cefazolin (Keflex), for the duration of the packing. This will aid in the prevention of a sinusitis or toxic shock syndrome. Leave the nasal packing in place for 1 to 7 days depending upon the amount of manipulation, the amount of bleeding, and Emergency Physician preference. Avoid nasal splinting and packing in patients with nasal fractures requiring a minor degree of manipulation,
especially when patients are assessed to have a low probability of follow-up and compliance. Consider applying an external splint in addition to the internal splint or nasal packing. Some authors do not advocate external splinting and its use is based on Emergency Physician preference. The splint serves to support the healing fracture and to remind the patient to keep their nose protected. Cleanse the skin of the nose and the surrounding area with alcohol. Apply benzoin solution to the nose and surrounding area. Allow the benzoin to dry and become tacky. Apply 1 inch wide paper tape in horizontal strips,
FIGURE 170-14. Placement of nasal reduction forceps. Note the rubber tubing over the outer tong to protect the skin.
FIGURE 170-15. The Asch forceps to elevate a frontal/inferior force fracture and straighten the associated deviated nasal septum.
CHAPTER 171: Nasal Septal Hematoma Evacuation
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septal or nasal dorsal hematomas. Internal and external splinting is useful to help insure good postoperative healing. Antibiotics are essential if nasal packing is applied.
171
Nasal Septal Hematoma Evacuation Michael Friedman, Meghan Wilson, and George Chiampas
INTRODUCTION FIGURE 170-16. Postreduction Denver splint applied after appropriate taping and midline vertical foam rubber placement.
layered downward from the nasofrontal angle to the tip of the nose. Apply benzoin solution over the tape. Allow the benzoin to dry and become tacky. Apply three to five layers of 2 inch wide orthopedic plaster of Paris over the tape. Alternatively, apply an appropriately sized Denver aluminum or Thermoplast splint over the tape (Figure 170-16). Ensure that the foam rubber strut is placed vertically over the midline length of the nose to prevent any skin necrosis. Place tape over the splint to secure it. Instruct the patient to return to the Emergency Department for excessive bleeding, increased pain, a purulent or foul nasal discharge, or a fever. Prescribe acetaminophen supplemented with narcotic analgesics as needed. Instruct the patient to avoid aspirin containing products and nonsteroidal anti-inflammatory drugs as they can increase the risk of bleeding. Arrange follow-up with an Otolaryngologist or Plastic Surgeon within 24 to 48 hours to assess the reduction and the need for further management.
COMPLICATIONS Pack (or repack) the nasal cavity, after providing adequate local anesthesia, if bleeding occurs. A septal hematoma is likely if a patient complains of persistent or excessive pain, has noticeable nasal widening, and has an ecchymotic septum. This must be evacuated as described in Chapter 171. Infection, cartilage necrosis, and disfiguring nasal dorsal saddling may occur if the septal hematoma is not evacuated. A nasal dorsal hematoma can occur as well and must be recognized and evacuated. Cerebrospinal fluid rhinorrhea and visual impairment are rare complications of the nasal manipulation, but more likely complications of the original trauma. Cerebrospinal fluid rhinorrhea can be delayed from the initial trauma until the edema has subsided. The reduction may be inadequate and require further closed or open reduction.
Soft tissue and bony injuries of the nose are common because the nose is centrally located and the most anteriorly protruding structure of the face.1 Suspect a nasal septal hematoma, although an uncommon complication of nasal trauma, in any individual who has sustained a nasal injury.2,3 All individuals who have sustained nasal trauma must undergo a careful examination of the septum and nasal passages, regardless of the mechanism of injury or the findings on external examination.2 Blunt trauma, either intentional or unintentional, is the most common cause of a nasal septal hematoma. Consider a bleeding diathesis if the hematoma develops after a seemingly trivial injury.2,4,5 Other etiologies include sports injuries and child abuse.5,6 Iatrogenic nasal septal hematomas following nasal septal surgery are probably more common than reported in the literature. Evaluate patients who have had recent nasal surgery and present with complaints of pain and nasal obstruction for a possible nasal septal hematoma. Nasal septal hematomas are characterized by severe localized nasal pain, tenderness on palpation of the nasal tip, and a cherrylike swelling or bluish discoloration of the nasal mucosa emanating from the septum that obstructs all or a portion of the nasal passage1–3,7 (Figures 171-1 & 2). Evacuation must be performed to prevent complications.1,2,4,5 Patients require bilateral nasal packing, oral antibiotics, and close follow-up with an Otolaryngologist to prevent complications following the evacuation of the hematoma.2,4,8 Distinguishing an uncomplicated nasal septal hematoma from one that has become infected is difficult, particularly if there has been a delay of several days in seeking medical attention following the injury.2 Nasal septal abscesses are a rare complication of nasal septal hematomas that occur following nasal trauma. Nasal septal abscesses generally are larger and more painful than uncomplicated nasal septal hematomas. The overlying nasal mucosa is inflamed and occasionally has an inflammatory exudate.2 Local extension of the infection, if left untreated, into the cavernous sinus with subsequent intracranial infection is the most important potential
SUMMARY Nasal fractures may be reduced and repaired in the Emergency Department using a closed technique. Perform the reduction, ideally within 3 hours of the injury, before significant edema occurs. It is otherwise best to wait until the swelling subsides in approximately 1 week. Repair nasal septal fractures at the same time as the nasal reduction. Severe fractures sometimes require an open reduction. Photographic and radiographic documentation can be important medicolegally as part of the preoperative evaluation. Drain any
FIGURE 171-1. Bilateral nasal septal hematomas creating a partial obstruction.
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SECTION 13: Otolaryngologic Procedures
FIGURE 171-2. A small left-sided nasal septal hematoma.
complication.5,8 The most common complication of a nasal septal abscess is cartilage necrosis that results in nasal structural collapse and a saddle nose deformity (Figure 171-3).
ANATOMY AND PATHOPHYSIOLOGY The nose is both a sensory organ and a respiratory organ. It performs an important function for the entire body by providing both physical and immunologic protection from the environment.9 The nose aids in the formation of basic speech sounds.9 The supporting structure of the nose consists of bone, cartilage, and connective tissue. The nose, on frontal view, is in the shape of a pyramid of which approximately the upper two-fifths comprise the bony vault and the lower three-fifths comprise the cartilaginous vault. The upper narrow end joins the forehead at the glabella and is referred to as the root of the nose. The two nares are separated from each other by a skin-cartilage septum known as the columella.9,10 The cartilaginous framework of the nose provides both its structure and function. The septal cartilage is avascular and receives its blood supply from the adherent mucoperichondrium. The skin covering the external nose is thin and contains an areolar type of subcutaneous tissue. The skin is loosely attached over the upper half. The skin over the lower half of the nose is intimately bound to the lower lateral cartilage and may sometimes be thick, fatty, and contain sebaceous glands.9,10 The precise mechanism for a nasal septal hematoma formation following nasal trauma is not known. Nasal septal hematomas are thought to occur when a mechanical force to the nasal cartilage results in rupture or leakage from the perichondrial blood vessels of the nasal septum. In instances where the nasal cartilage is fractured, blood may dissect through the fracture line and form bilateral septal hematomas. Most nasal septal hematomas are secondary to a fracture or surgery. Thus, they almost always distend the mucoperichondrium on both sides of the nose. Accumulation of the extravasated blood strips the perichondrium from the cartilage, forming a closed space in which the blood accumulates (Figure 171-2). The nasal septal hematoma, when not recognized initially and evacuated promptly, can expand and mechanically obstruct the blood vessels that supply the nasal cartilage. Pressure-induced avascular necrosis of the nasal septal cartilage can develop rapidly because there is no alternative blood supply to the cartilage.1–3,7 The accumulated blood and necrotic tissue can form a nidus for infection from bacteria that colonize the nasal mucosa.1–3,7 Cartilage necrosis subsequently leads to the saddle nose deformity. The term “saddle nose deformity” is a nonspecific description of a nose with a depression over its dorsal surface9 (Figure 171-3). The saddle nose deformity is a result of the nasal septal cartilage becoming ischemic from loss of its blood supply, subsequent nasal septal cartilage resorption and collapse, and the lack of support for the nasal bridge. The deformity is the ultimate result of a nasal septal hematoma or abscess not being evacuated. Necrosis with subsequent fibrosis may develop causing a permanent thickening
FIGURE 171-3. The saddle nose deformity.
or absorption of the nasal septum with partial obstruction of the nasal airway.7–9 The sphenopalatine branches of the internal maxillary artery and the ethmoidal arteries from the ophthalmic artery supply the internal nose. The veins terminate in the anterior facial and ophthalmic veins.10 Venous drainage is clinically important in understanding the complications of a septal abscess. Branches of the trigeminal nerve provide sensory innervation to the nose.9,10
INDICATIONS Any significant nasal septal hematoma requires evacuation. A nasal septal hematoma may progress to form an abscess with associated complications of avascular necrosis of the nasal septum, meningitis, or cavernous sinus thrombosis in as little as 3 to 4 days.7,8 It is not urgent to evacuate a simple nasal septal hematoma in the Emergency Department as complications occur over a period of days. It is essential, however, to identify a nasal septal hematoma so that a treatment plan is initiated and to rule out a septal abscess that does require immediate evacuation.5
CONTRAINDICATIONS There are no absolute contraindications to the evacuation of a nasal septal hematoma. Address any life-threatening or serious injuries or conditions prior to drainage of the nasal septal hematoma. This procedure requires a cooperative patient to prevent secondary iatrogenic injury. Any patient that is uncooperative, unable to follow instructions, very young, or that has an altered mental status may require evacuation under procedural sedation or general anesthesia.
EQUIPMENT • Headlight • Nasal speculum • Nasal vasoconstrictor (e.g., 2% ephedrine. 0.25% oxymetazoline or phenylephrine) • Nasal anesthetic (e.g., 4% cocaine, 2% pontocaine, and 4% lidocaine)
CHAPTER 171: Nasal Septal Hematoma Evacuation
• • • • • • • • • • • • • •
Nasal atomizer device, optional Alcohol swabs Povidone iodine or chlorhexidine solution Cotton-tipped applicators 1 mL and 10 mL syringes 25 or 27 gauge needle, 1½ inches long Local anesthetic solution containing epinephrine, lidocaine, or bupivacaine #15 surgical blade on a handle Frazier suction catheter Suction source and tubing Nasal speculum Bayonet forceps Nasal tampon or sponge Iodoform gauze
PATIENT PREPARATION Explain the risks, benefits, complications, and aftercare of the procedure to the patient and/or their representative. Obtain a signed consent for the procedure. Aseptic technique should be followed and maintained throughout the procedure. The procedure is considered clean, but not sterile, as the nasal mucosa can never be sterilized. It is crucial, however, that the instruments are sterile. Administer anesthesia for the evacuation of a nasal septal hematoma by one of two routes: topical application with supplemental infiltration or a regional block. Some authors recommend using both techniques. However, most nasal septal hematomas can be adequately evacuated with topical anesthesia supplemented by local infiltration.7 Dampen the swabs of four cotton-tipped applicators with either a solution of 2% pontocaine with ephedrine or cocaine. Insert a nasal speculum to expose one nostril. Gently insert the applicator beneath the roof of the nose so that it reaches the branches of the anterior ethmoidal nerve. Pause until some vasoconstriction and anesthesia takes place, if it meets resistance on insertion, and advance the applicator further (Figure 171-4). Pass
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an applicator into the nasal fossa and move it from the floor of the nasal vestibule, across the midportion of the inferior turbinate, and reaching the posterior aspect of the middle turbinate in the region of the sphenopalatine foramen.11 Infiltrate a maximum of 0.5 mL of local anesthetic solution containing epinephrine, if additional anesthesia is desired, through the mucoperichondrium and circumferentially around the hematoma. An atomizer or nasal spray bottle can provide an alternative and commonly used method for nasal septal anesthesia. While an actual atomizer is not often available in the Emergency Department, its use is less painful to the patient than the application of cottontipped applicators into the nasal cavity. Alternatives to an atomizer are devices to attach to a syringe to atomize the contents or using a commercially available nasal spray container after emptying its contents. Mix equal amounts of 2% pontocaine or 4% lidocaine with ephedrine and place this in the atomizer or nasal spray bottle. Insert the nasal speculum to gain access to the entire nasal cavity. Open the nasal speculum vertically to expose as much of the nasal septum as possible. Insert the atomizer or nasal spray bottle into the nostril. Instill two puffs of solution into the nostril. Allow 5 to 10 minutes for the anesthetic to take effect. Infiltrate a maximum of 0.5 mL of local anesthetic solution containing epinephrine, if additional anesthesia is desired, through the mucoperichondrium and circumferentially around the hematoma. Confirm the presence of a septal hematoma. Compress the area with a cotton-tipped applicator. The bulge from the hematoma is compressible with the applicator. It should not shrink with the application of a topical vasoconstrictor.2,6
TECHNIQUES ASPIRATION Some authors feel that simple aspiration with an 18 gauge needle may be adequate for a small, early hematoma. Most patients require a more extensive evacuation as clotted blood cannot be removed with aspiration. Since blood clots form within minutes and remain in clotted form for days, needle aspiration is generally not effective. Simple aspiration may, however, be used to diagnosis a septal hematoma.6–8 Insert the nasal speculum. Open the nasal speculum vertically so that the nasal septum is maximally visible. Instruct an assistant to hold the nasal speculum in position and open, allowing the Emergency Physician to have both hands free to perform the procedure. Insert an 18 gauge needle, attached to a 10 mL syringe, into the nasal septal hematoma. Aspirate the contents of the hematoma. No additional procedure is necessary if the hematoma can be completely evacuated by aspiration. Simple clinical assessment of the septum is the guide to determine if the hematoma has been evacuated. Apply a nasal pack as described below.
INCISION AND DRAINAGE
FIGURE 171-4. Cotton swab technique for nasal septal anesthesia.
The incision and drainage technique is the primary procedure to drain a nasal septal hematoma. Cleanse the skin surrounding the nares of any dirt and debris. Apply an alcohol swab, povidone iodine, or chlorhexidine to the area and allow it to dry. Insert the nasal speculum. Open the nasal speculum vertically so that the nasal septum is maximally visible. Instruct an assistant to hold the nasal speculum in position and open, allowing the Emergency Physician to have both hands free to perform the procedure. Make a 1.0 to 2.0 cm long vertical incision, with a #15 scalpel blade, in the septal mucoperichondrium overlying the hematoma (Figure 171-5). Be cautious to not cut into the cartilaginous septum. The length of the incision depends upon the size of the nasal septal hematoma. Some authors prefer to use an L-shaped incision in the mucoperichondrium.12–16
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FIGURE 171-5. Nasal septal hematoma with markings for a vertical incision through the mucoperichondrium.
FIGURE 171-6. Iodoform gauze is placed between the separated mucoperichondrium and the cartilaginous septum.
These authors feel that this incision allows the mucoperichondrium to reposition flat against the cartilaginous septum. The choice of incision type is left to the preference of the Emergency Physician. Use the Frazier suction catheter to gently evacuate any clot or necrotic debris from the hematoma cavity. Clots are difficult to evacuate by suction and may require mechanical removal. Always send a sample of the fluid or hematoma to the laboratory for Gram’s stain, anaerobic cultures, and aerobic cultures.2,7,8 Apply topical antibiotic ointment over the incision, a wick, and nasal packing as described below. A bilateral septal hematoma can, almost always, be evacuated from one side. Apply gentle pressure to the contralateral hematoma to express it out the incision. Make a second vertical incision contralaterally, either anterior or posterior to the first incision to prevent septal perforation, if complete evacuation is not achieved unilaterally.
report such devices to be significantly more comfortable than traditional gauze packing. This, coupled with the ease of insertion when compared to gauze packing, has made such devices very popular. Place the patient’s head in the sniffing position. Coat a nasal tampon with a water-soluble antibiotic ointment. Insert the nasal speculum to obtain adequate visualization of the nasal septum. Grasp the nasal tampon with a bayonet forceps. Introduce the forceps with the nasal tampon in a horizontal position through the speculum. Be careful to not tear the incision in the mucoperichondrium open or to dislodge the wick. Place the nasal tampon on the floor of the nasal cavity and against the nasal septum.8 Withdraw the bayonet forceps and the nasal speculum. Repeat the nasal packing procedure on the contralateral side. Both nasal cavities must be packed to maintain the septum in the midline, prevent bowing of the septum into the contralateral nasal cavity, and the reaccumulation of the hematoma. Refer to Chapter 172 regarding the complete details of nasal packing.
WICK INSERTION Insert a wick of 1/8 inch iodoform gauze through the incision (Figure 171-6). Allow 1 inch of the wick to extend into the nasal cavity for easy removal. Be careful to ensure that the wick is flat between the mucoperichondrium and the cartilaginous septum. Do not pack the cavity with the wick. Some authors recommend inserting a Penrose drain, or a piece of one, instead of the iodoform gauze.6 This has not been found to be beneficial when compared to iodoform gauze.6 The Penrose drain can be a substitute if iodoform gauze is not available or the patient is allergic to iodine.
NASAL PACKING Apply bilateral nasal packs following the successful drainage of a septal hematoma. Packing inhibits the reaccumulation of the hematoma, or serous fluid, thereby preventing the severe complications associated with a septal hematoma. The use of commercially available nasal packing devices, such as nasal tampons or sponges, provides adequate protection against reaccumulation. Patients
PEDIATRIC CONSIDERATIONS Nasal septal hematomas can occur at any age. The diagnosis and treatment are the same for adult and pediatric patients. Generally, however, any treatment for children would be done under procedural sedation in the Emergency Department or general anesthesia in the operating room.
AFTERCARE Proper follow-up is vital to prevent any infectious process or cosmetic deformity. All patients must be reevaluated within 24 hours and again in 48 hours for removal of the nasal packs. Prescribe acetaminophen and narcotic analgesics for pain control. Prescribe broad-spectrum antibiotics, specifically those with staphylococcal coverage, as prophylaxis against infection and the development of a septal abscess.6 Instruct the patient to avoid nonsteroidal antiinflammatory drugs as they increase the risk of bleeding. Provide all patients with proper discharge instructions. They should
CHAPTER 172: Epistaxis Management
return to the Emergency Department immediately if they experience increased pain, bleeding, or a fever. Refer all patients to an Otolaryngologist within 24 hours.
COMPLICATIONS The most common acute complication of a nasal septal hematoma is an abscess or cosmetic deformity. Complications are primarily related to incomplete evacuation or reaccumulation of the hematoma. This may be avoided by adequate removal of the hematoma with suction, placement of an iodoform gauze wick, and bilateral nasal packing. An abscess may result in ascending infections including meningitis and cavernous sinus thrombosis. Staphylococcus aureus is the primary pathogen isolated from the majority of reported cases, regardless of patient age. Prescribe appropriate prophylactic antibiotics.2,5,6 Many patients cannot tolerate complete hematoma evacuation under local anesthesia. When complete evacuation is not performed, consult an Otolaryngologist and schedule the patient for evacuation under anesthesia within 24 hours. Early and/or appropriate treatment may not prevent complications if the nasal septal cartilage is already ischemic at the time of the procedure. Other complications of nasal septal hematoma drainage are rare and include nasal bleeding, inadequate evacuation, and septal perforation. Nasal bleeding can usually be controlled with the prescribed packing. Incomplete removal of the hematoma is not a serious problem if identified. A nasal septal hematoma may reoccur if the incision is made on opposite sides of the septum. Limit the incision to one side if possible. The second incision, if required, on the contralateral side must not oppose the first incision.
SUMMARY A nasal septal hematoma is a rare but potentially serious complication of nasal trauma. Proper management consists primarily of early recognition, prompt evacuation, wick insertion, and bilateral nasal cavity packing. Administration of antimicrobial therapy is necessary to prevent or treat a secondary nasal abscess. Follow-up with an Otolaryngologist is required within 24 hours of the procedure to evaluate for the reaccumulation of the hematoma and/or an abscess. These patients require continual follow-up until the nasal septum is healed.
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Epistaxis Management Stephen M. Kelanic, David D. Caldarelli, and Eric F. Reichman
INTRODUCTION Epistaxis is an extremely common condition in the United States with an incidence estimated at 10 per 10,000 people per year.1 It is a common reason for patient visits to the Emergency Department. There is an early peak in those less than 10 years of age.2 The frequency of epistaxis decreases in the teens and begins to progressively increase after 20 years of age, with the highest frequency in the elderly.2 Epistaxis usually is the result of well-localized intranasal trauma. However, it may be the initial sign of a more serious underlying systemic illness. Epistaxis is often self-limited and can be managed conservatively. Epistaxis can also manifest itself as a profuse spontaneous hemorrhage that is extremely difficult to control and result in aspiration, hypotension, cardiovascular collapse, syncope, and airway compromise.
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The proper management of epistaxis and the prevention of adverse consequences depend on a timely and thorough evaluation of the patient as well as the appropriate intervention. The Emergency Physician must be familiar with a variety of techniques to control intranasal hemorrhage.
ANATOMY AND PATHOPHYSIOLOGY An understanding of the vascular anatomy of the nasal cavity is essential to efficient and immediate control of nasal bleeding. The blood supply to the sinonasal cavity arises from both the internal and external carotid artery system (Figure 172-1). The sphenopalatine artery arises as one of the terminal branches of the internal maxillary artery, a branch of the external carotid system, and is the primary blood supply to the sinonasal cavities. The anterior and posterior ethmoid arteries, terminal branches of the internal carotid system, supply blood to the superior straits of the nose. The superior labial branch of the facial artery supplies the anterior nasal cavity and anastomoses with branches from the anterior ethmoid artery and the sphenopalatine artery in an area of the anterior nasal septum known as Kiesselbach’s plexus or Little’s area (Figure 172-2). It has been estimated that 90% of all nasal bleeding occurs in the area of Kiesselbach’s plexus.3 This is particularly true for children and young adults. Older adults tend to bleed from the posterior nasal cavity, from branches of the sphenopalatine and posterior ethmoidal arteries. This has been attributed to arteriosclerosis.3 Epistaxis may result from numerous local and/or systemic factors that damage the delicate mucosal lining of the nasal cavity and expose the underlying vasculature. The most common cause of epistaxis is accidental or self-inflicted trauma, often from digital manipulation of the nasal mucosa (i.e., nose picking). This eventually heals and crusts over but is subject to repeated irritation and bleeding when the patient sneezes or blows their nose. The anterior source of this bleeding makes it very easy to treat. High-velocity trauma to the region of the midface and skull base may be manifest as a severe, life-threatening hemorrhage that may be extremely difficult to control. Local inflammatory reactions due to acute upper respiratory infections, allergic rhinitis, and chronic sinusitis may cause epistaxis.4 The mucosa becomes inflamed, hypervascular, and is easily disrupted with forceful nose blowing. The presence of an intranasal foreign body may inflame the nasal mucosa, with consequent granulation tissue and bleeding. This should be expected if the bleeding is unilateral and associated with nasal obstruction and foul rhinorrhea. Epistaxis may be attributed to a nasal septal deformity.5 The deflected nasal septum creates turbulent airflow that desiccates the mucosa and leads to crusting and bleeding. Epistaxis attributed to nasal septal deviation presents just posterior to the deflection and may be difficult to control. Nasal septal perforations bleed frequently and easily from mucosal irritation and granulation tissue. Postoperative bleeding as the result of sinonasal surgery—such as septoplasty, rhinoplasty, turbinectomy, and endoscopic sinus surgery—may also be encountered. Blood-tinged nasal secretions are to be expected for the first 2 weeks after surgery. Severe epistaxis may occur during the first postoperative week, with an estimated incidence ranging from 0.9% to 8.9%.6 The bleeding is usually posterior, brisk, and may be difficult to control. Consult the Otolaryngologist who performed the procedure in all cases of postoperative bleeding. Nasal bleeding may be the first sign of a sinonasal neoplasm. The bleeding is usually intermittent and often accompanied by nasal obstruction and pain. Severe bleeding is unusual except in
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Supraorbital artery
Ophthalmic artery
Supratrochlear artery Infratrochlear artery
Frontal artery
Superior peripheral arcade
Superficial temporal artery
Superior marginal arcade
Zygomaticoorbital artery
Inferior marginal arcade
Transverse facial artery
Maxillary artery Infraorbital artery Internal carotid artery Zygomaticofacial artery External carotid artery
Facial artery
FIGURE 172-1. The blood supply of the nasal cavity arises from the internal and external carotid artery systems.
Anterior ethmoid artery Posterior ethmoid artery Sphenopalatine artery
Kiesselbach's plexus
the case of juvenile nasal angiofibromas, which should be suspected in adolescent males. Patients without identifiable local causes for epistaxis most likely suffer from an underlying systemic process. Consider the possibility of a defect in the coagulation cascade. Hypertension is often cited as a significant factor for epistaxis. Studies have been unable to demonstrate a significant difference in the prevalence of epistaxis in patients with hypertension versus patients without hypertension.7,8 Nonsteroidal anti-inflammatory drugs and aspirin containing products have been associated with epistaxis.9,10 Osler-Weber-Rendu disease is an autosomal dominant inherited condition in which the blood vessel walls lack contractile elements. Consequently, prolonged heavy bleeding occurs from relatively minor insults, as the vessels are unable to contract and allow clotting to take place. The patient’s coagulation profile is normal and the diagnosis is made by the family history. Other systemic etiologies include alcoholism, blood dyscrasias, liver disease, malnutrition, and pregnancy.
INDICATIONS Superior labial artery
Greater palatine artery
FIGURE 172-2. Arterial supply to the nasal septum and Kiesselbach’s plexus.
A patient with epistaxis must be evaluated expediently. All patients with epistaxis require a thorough examination and control of the bleeding. Epistaxis that has resolved still requires management to prevent rebleeding.
CHAPTER 172: Epistaxis Management
CONTRAINDICATIONS There are no contraindications to the management of epistaxis. Manage any unstable vital signs, unstable airway, life- or limbthreatening injuries, or any complications related to blood loss (e.g., hypotension, chest pain, syncope, etc.) before managing the epistaxis. In the interim, apply a nose clip or a nasal sponge/tampon to control the bleeding. A thorough examination and more definitive means of control can be performed after the patient has been stabilized.
EQUIPMENT • • • • • • • • • • • • • • • • • • • • • • • • •
Nose clip Headlight or overhead light source Yankauer suction catheter Frazier suction catheters, #5 and #7 Nasal speculum, short and medium lengths Bayonet forceps Kidney basin Weeder metal tongue blade or wooden tongue depressors Gown, gloves, face mask with an eye shield or goggles Cotton balls Topical anesthetics and vasoconstrictors (Table 172-1) Silver nitrate applicator sticks Petrolatum (e.g., Vaseline) impregnated gauze ribbon, 0.5 inches wide Synthetic nasal sponges/tampons, various lengths Nasal balloons (anterior, posterior, anterior and posterior) 14 French Foley catheter with a 30 mL balloon Umbilical clamp Gelfoam 4 × 4 gauze squares Surgicel ENTaxis nasal packing 3 inch long dental rolls or tonsil packs, or 3 × 36 inch Vaseline gauze Umbilical tape or 0 silk suture Red rubber catheters Lubricant
TABLE 172-1 Anesthetics and Vasoconstrictors of the Nasal Mucosa Anesthetics 4% cocaine 4% lidocaine 2% pontocaine Topical anesthetic spray (e.g., Cetacaine) Vasoconstrictors 4% cocaine 3% ephedrine 1:1000 epinephrine 0.5% oxymetazoline 0.5% to 1.0% phenylephrine 0.05% to 0.10% xylometazoline Anesthetic and vasoconstrictor combinations 4% cocaine 0.25 mL of 1:1000 epinephrine and 20 mL lidocaine mixture 4% lidocaine and 0.05% oxymetazoline, 50:50 mixture 4% lidocaine and 0.5% to 1.0% phenylephrine, 50:50 mixture
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The list of equipment required to manage a patient with epistaxis is quite long. Most Emergency Departments keep all the required equipment, except medication, in a rolling cart or tackle box. This system allows for more efficient stocking and restocking. It is also more efficient to have all the required equipment readily available in one convenient and portable location. Single patient use and disposable nosebleed trays are commercially available (e.g., Centurion ENT/Nosebleed Tray, Tri-State Hospital Supply Corp., Howell, MI). They contain all the required instruments but lack the medications and other supplies.
PATIENT PREPARATION Explain the procedure, its risks, and its benefits to the patient and/or their representative. Obtain a signed informed consent for the procedure. Ensure that the patient has a thorough understanding of the postprocedural care instructions and follow-up requirements. Position the patient sitting in an upright multipositional procedure chair. Alternatively, place the patient sitting upright on a gurney with the back elevated. Prepare the wall suction unit to make sure that it is working. Apply suction tubing and a suction catheter to the suction source. The importance of good lighting cannot be overemphasized. Apply a headlamp if one is available. An alternative is an overhead adjustable light source. Position the light so that it is aimed in the patient’s mouth. The overhead light often hits the examiner in the head, casts shadows, and is too bright for the patient’s eyes. It is also difficult to position properly as both of the examiner’s hands must be used for the procedure. Instruct the patient to blow their nose firmly, one nostril at a time, in order to evacuate the nasal cavities before the examination. This allows the anterior nasal septum, Kiesselbach’s plexus, the nasal vestibule, the inferior turbinate, and the floor of the nasal cavity to be examined. Inspect the posterior oropharynx for active bleeding using the Weeder tongue blade or a wooden tongue blade. Insert a short nasal speculum to evaluate each side of the anterior nasal cavity. Open the speculum vertically. Suction out any blood and blood clots with the Frazier suction catheter. Consider a posterior site of bleeding if the source is difficult to localize. A patient will occasionally present with bilateral epistaxis. It is sometimes difficult to determine from which side the bleeding is originating. Ask the patient which side started bleeding first. This is usually the side where the bleeding point can be found. Vasoconstrict and anesthetize the nasal mucosa (Table 172-1). Decongest the nasal mucosa with an aerosolized agent. Instruct the patient to sniff in deeply after the spray is applied. Allow 3 to 5 minutes to pass for the vasoconstriction to occur. Apply a topical anesthetic spray to the nasal passageway. Spraying achieves excellent vasoconstriction and anesthesia as the agents diffuse through the entire nasal cavity and pharynx. It is possible to anesthetize and vasoconstrict the nasal mucosa in one step by using cocaine or a combination of an anesthetic and vasoconstrictor agent (Table 172-1). Alternatively, place cocaine-soaked pledgets into the nasal cavity. Direct the pledgets along the floor of the nose, against the nasal septum, and toward the superior straits of the nose. Monitor the patient’s vital signs when vasoconstrictors are applied. There are numerous techniques to manage epistaxis. These include the use of absorbable packs, electrocautery, Foley catheters, gauze rolls, intranasal balloon catheters, petrolatum impregnated ribbon gauze, nasal tampons or sponges, and silver nitrate. The technique and material of choice depend upon the location of the bleeding (anterior vs. posterior) and Emergency Physician preference. Different techniques and equipment are required to control anterior versus posterior bleeding.
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RADIOLOGIC STUDIES Imaging is not routinely indicated for the initial evaluation and management of epistaxis in the majority of cases. Damrose and Maddalozzo reviewed CT scans of pediatric patients who were referred for evaluation of epistaxis.11 While 79% of the studies demonstrated some abnormality, none of the patients were found to have a neoplasm. They concluded that routine imaging of the sinuses is not recommended. CT imaging of the paranasal sinuses and facial bones should be considered when there is a history of facial trauma or when there is a high index of suspicion for a neoplasm.
ANTERIOR EPISTAXIS MANAGEMENT TECHNIQUES Anterior nasal packing is required when local measures fail to control epistaxis. This may be due in part to anterior or structural problems in which the bleeding source cannot be identified. It may also be due to heavy or profuse bleeding. The premise behind placing nasal packing is that it provides mechanical pressure and tamponades the bleeding site.12 Note that this is an uncomfortable procedure; therefore, the previously described steps for applying topical anesthesia should be undertaken.
ABSORBABLE PACKING Diffuse bleeding is frequently encountered in patients with coagulopathies and blood dyscrasias. The trauma of inserting the nasal packing (e.g., a tampon or petrolatum gauze) can lead to more serious bleeding. A piece of Gelfoam sponge or oxidized cellulose (e.g., Surgicel) is often effective. These substances, coated with an antibiotic ointment (e.g., Bacitracin), provide adequate pressure and hemostasis without extreme trauma to the nasal mucosa. This packing does not need to be removed and will slowly dissolve with the use of a topical saline spray, which may be started within 24 hours of the packing being placed. The two most commonly used absorbable dressings are Gelfoam and Surgicel. Gelfoam is an absorbable gelatin sponge that is readily available and inexpensive. It forms a scaffold for the formation of a blood clot. Surgicel is composed of oxidized and regenerated cellulose. It promotes coagulation better than Gelfoam. Unfortunately, Surgicel results in delayed healing and its use should be reserved for persistent bleeding or when Gelfoam is not available. Absorbable packs may be used for primary and secondary hemostasis. Apply a piece of Gelfoam or Surgicel directly over the site of discrete bleeding or diffuse oozing. The material may be used for secondary hemostasis and be placed over an area that has clotted and stopped bleeding. This can serve as a “Band-Aid” to help prevent the clot from dislodging prematurely and the bleeding to restart. It can be placed over areas that have been chemically or electrically cauterized. An absorbable pack can be placed prior to packing the nasal cavity with a sponge/tampon or gauze. The absorbable pack will prevent the clot from becoming dislodged when the sponge/ tampon or gauze is removed. Insert the nasal speculum and identify the scabbed or bleeding site. Apply a piece of Gelfoam or Surgicel over the site. Allow a clot to form onto the absorbable packing. The nasal cavity may then be packed with a sponge/tampon, petrolatum gauze, or a balloon catheter if the Emergency Physician chooses. Two additional absorbable dressings are topical thrombin and collagen. They are expensive, not usually available in the Emergency Department, and should be limited to circumstances where other hemostasis methods have failed. Topical thrombin is made from bovine thrombin. Place a piece of Gelfoam saturated
with thrombin over the bleeding site. Thrombin converts fibrinogen to fibrin, bypassing the coagulation cascade, to form a clot. Collagen is available in multiple forms from a variety of sources. It promotes platelet aggregation and forms a scaffold for the formation of a clot. Cover the bleeding site with collagen followed by a piece of Gelfoam.
CHEMICAL CAUTERIZATION The location of the bleeding is usually within the anterior nasal cavity, specifically on the anterior nasal septum. Sometimes no active bleeding is found at the time of the evaluation. Suctioning of the nasal cavity will remove clots and may allow the site to bleed and be visualized. A scabbed excoriation or an exposed blood vessel may be found along the nasal septum. Chemically cauterize these areas using silver nitrate applicators. Insert the nasal speculum and identify the scabbed site or the exposed vessel. Apply the silver nitrate under direct vision by rubbing the applicator on the area immediately surrounding the scab or blood vessel. Apply the silver nitrate for 3 to 10 seconds. Do not apply the applicator in any one spot for more than 10 seconds. This may cause mucosal necrosis and damage to the underlying cartilaginous septum. Do not apply the silver nitrate too excessively or in the same spot on both sides of the septum, as this may result in a septal perforation. Apply a topical antibiotic ointment to the area. Consider placing a piece of Gelfoam or Surgicel over the site to help stabilize the clot. A relatively dry field is required to use the silver nitrate applicator. Moderate-to-severe bleeding results in the silver nitrate coagulating the blood. It will not contact the mucosal tissue and bleeding will continue. Attempt to simultaneously suction the blood while using the silver nitrate applicator. Unfortunately, the suction often pulls off the coagulum and the bleeding continues. A final technique is to apply the silver nitrate centripetally around the bleeding site. This will cauterize the feeder vessels and may stop the bleeding. Do not cauterize an area over 0.75 cm in diameter, as this can result in damage to the underlying cartilaginous septum. Pack the nasal cavity with a sponge/tampon, petrolatum gauze, or a balloon catheter if these techniques fail.
ELECTRICAL CAUTERIZATION Electrocautery can effectively control bleeding if the site is identified. This technique is reserved for the experienced Otolaryngologist. It can cause significant damage to the mucosa and cartilage in inexperienced hands. The technique of electrocautery is not discussed for these reasons.
RIBBON GAUZE PACKING The traditional technique of anterior nasal packing consists of using 0.5 inch wide petrolatum impregnated gauze ribbon (Figure 172-3). This technique is extremely effective but not often used as it is cumbersome, time-consuming, and simpler methods exist (e.g., silver nitrate cautery, sponges/tampons, and balloon catheters). Insert the nasal speculum. Grasp one end of the petrolatum gauze with a bayonet forceps. Insert the petrolatum gauze into the nasal cavity and along the nasal floor (Figure 172-3A). Tightly pack the nasal cavity in a layered fashion from bottom to top, extending as far back as possible toward the choanal arch (Figure 172-3B). Be careful to avoid injuring the mucosa overlying the septum and the turbinates. Cut the petrolatum gauze so that it protrudes approximately 2 cm from the nostril. Tape this loose end to the patient’s cheek so that it does not accidentally pull the packing out. The
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FIGURE 172-3. Anterior nasal packing using petrolatum (e.g., Vaseline) impregnated gauze ribbon. A. Insert a nasal speculum and begin packing inferiorly to superiorly. B. The gauze-packed anterior nasal cavity.
packing is later removed by gently pulling on this free end of gauze ribbon protruding from the nostril. The pressure of one-sided anterior nasal packing can bow the septum contralaterally, allowing the packing to “loosen” and the bleeding to restart. Consider packing the contralateral anterior nasal cavity to maintain the septum in the midline and exert pressure on the bleeding site.
EXPANDABLE NASAL SPONGES/TAMPONS One of the easiest, quickest, and most effective techniques to control anterior epistaxis is to insert an expandable sponge or tampon (e.g., Merocel packing). These packs are particularly useful when the bleeding is diffuse, a specific site cannot be clearly identified, or the bleeding is heavy. The packs come in various sizes (4.5, 6, 8, and 10 cm), shapes, and styles (Figure 172-4). Initially quite rigid, they soften and expand with the absorption of saline or surrounding blood. A 4.5 or 6 cm sponge is generally adequate for anterior epistaxis. Prepare the sponge/tampon. Cut the string from the sponge/ tampon as it is not necessary to remove the packing. The sponge/ tampon is barely visible when properly inserted. The string hanging from the nostril is irritating to the patient and not cosmetically appealing. Lightly coat two-thirds of the sponge/tampon with a
FIGURE 172-4. Various sizes, shapes, and styles of nasal sponges/tampons.
non-water-soluble lubricant (e.g., Vaseline) or antibiotic ointment (e.g., Neosporin). This will prevent premature expansion of the tampon from a water-soluble lubricant or antibiotic ointment, nasal secretions, or blood. Insert and open the nasal speculum within the affected nasal cavity. Grasp the unlubricated end of the sponge/tampon with a bayonet forceps or the dominant thumb and index finger. Insert and advance the sponge/tampon just lateral to the nasal septum, in a vertical position, with the length of the pack directed along the floor of the nose (Figure 172-5A). Advance the sponge/tampon until it is completely within the nasal cavity. The sponge/tampon will expand from the blood and secretions within the nasal cavity (Figure 172-5B). Slowly drip 1 to 3 mL of tap water or saline onto the unlubricated tip of the sponge/tampon to help it expand more rapidly. Inspect the oropharynx for bleeding. Persistent bleeding may be due to the septum bowing contralaterally. Pack the contralateral anterior nasal cavity with a sponge/tampon of equal length and size. Observe the patient for oozing or bleeding anteriorly or posteriorly. Continued bleeding requires removal of the sponge/tampon from the bleeding nasal cavity and insertion of a larger one, two small ones, or Vaseline gauze packing. Keep several helpful hints in mind when using the nasal sponges/tampons. Trim large sponges/tampons to 5 to 6 cm in length. The extra length is not required for anterior epistaxis, is uncomfortable for the patient, and is more difficult to remove. The Rhino Rocket is a sponge/tampon within a plastic syringe-like device. Remove the sponge/tampon from the syringe-like device before inserting it. The device can generate significant force and result in mucosal tears, septal injuries, and turbinate injuries. Insert and advance the sponge/tampon rapidly to prevent premature expansion. There is no advantage to using a non-water-soluble antibiotic ointment versus a lubricant. The antibiotic ointment is more expensive and its antibacterial activity lasts only 2 to 4 hours. Insert two sponges/tampons side by side if the patient has a large nasal cavity. Removal of the sponge/tampon is simple and quick. Apply 1 to 2 mL of tap water, saline, or a vasoconstrictor in a dropwise fashion to the tip of the sponge/tampon in the nostril. This will thoroughly hydrate the packing and ensure that it can be withdrawn atraumatically. Allow 5 to 10 minutes to ensure that the packing is completely hydrated. Grasp the end of the sponge/tampon with a hemostat. Place a kidney basin under the patient’s nose. Pull quickly and parallel to the floor of the nasal cavity to remove the packing. Epistaxis after removal is often due to dislodgement of the clot. Use an absorbable pack or silver nitrate to stop the bleeding.
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FIGURE 172-5. The expandable nasal sponge/tampon. A. Insertion along the floor of the nasal cavity. B. The expanded state.
Look at the sponge/tampon to identify the blood spot and the location of the bleeding.
INFLATABLE NASAL BALLOON CATHETERS The development of plastic inflatable balloon catheters has simplified the management of epistaxis. The nasal balloons are easy to use and quick to place. They are available in a variety of sizes and shapes (Figure 172-6). They are available with anterior balloons, posterior balloons, or dual balloons. The anterior balloon fills the nasal cavity and acts as an anterior pack. The posterior balloon occludes the nasopharynx and acts as a posterior pack. The inflatable balloons are more expensive than other methods used to manage epistaxis. The increased cost is offset by decreased Emergency Physician contact time as compared with that required for petrolatum (e.g., Vaseline) gauze packing. The balloons have a maximal inflatable volume that is manufacturer-specific, noted on the packaging, and noted on the balloon’s inflation hub. Prepare the equipment. Select an anterior balloon catheter. A dual-balloon catheter may be used if an anterior balloon catheter is not available. Inflate the balloon with air to just below its maximum capacity. Observe and palpate the balloon for leaks. It may also be inflated in a cup of water to look for leaks. Completely deflate the balloon. Apply a lubricant over the catheter and balloon. Insert the nasal speculum. Insert the catheter with the distal bevel toward the nasal septum. This prevents the distal end of the catheter from getting caught on the turbinates, damaging the mucosa overlying the turbinates, and causing a second source of
FIGURE 172-6. Examples of some inflatable nasal balloon catheters.
epistaxis. Advance the catheter along the floor of the nasal cavity until just the inflation hub is protruding from the nostril (Figure 172-7). Inflate the balloon with air and 10 mL less than the maximum volume of the balloon (Figure 172-7). Do not use saline or water to inflate the balloon. Rupture of the balloon can result in aspiration if it is filled with liquid. Do not inflate the balloon with more than the manufacturer’s recommended volume. If the patient complains of pain, the balloon may have been inflated larger than the nasal cavity. Slowly deflate the balloon in 2 mL increments until the pain subsides. Observe the patient for continued bleeding. Increase the volume of the balloon to the maximum volume if the patient does not complain of pain. The balloon may cause a bowing of the septum to the contralateral side. If the bleeding continues, pack the contralateral anterior nasal cavity to keep the septum in the midline. Observe the patient for further bleeding from the nostril or into the nasopharynx. Continued bleeding suggests that the source is high in the nasal cavity or posterior. The inflatable balloons do not always fill the upper portion of the nasal cavity. Deflate the balloon, pack the high anterior nasal cavity with petrolatum gauze, and reinflate the balloon. Observe the patient for continued bleeding that would require a posterior pack, as described in the following sections.
RAPID RHINO The Rapid Rhino Nasal Pac (Applied Therapeutics Inc., Tampa, FL) is a form of balloon catheter. The balloon is covered with a
FIGURE 172-7. Inflation of an anterior balloon catheter to control anterior epistaxis.
CHAPTER 172: Epistaxis Management
FIGURE 172-8. The ENTaxis nasal packing (Boston Medical Products, Westborough, MA).
hydrocolloid fabric that is self-lubricating, easy to insert, and promotes platelet aggregation. It is available in different lengths to accommodate children, anterior epistaxis, and posterior epistaxis. It is also available in a variety of sizes in both a unilateral balloon design and a bilateral balloon design with a single inflation port. The bilateral model allows for bilateral nasal packing with a single inflation port, maintaining equal pressure on both sides of the nasal septum. Dip the fabric covered balloon in sterile water for approximately 30 seconds to prelubricate it before insertion. Insert the balloon and inflate it as described previously. The advantage to this product is the ease of insertion, minimal bleeding upon removal, and patient comfort.13
ENTaxis NASAL PACKING A relatively new anterior nasal packing is the ENTaxis (Figure 172-8). It is a natural polymer derived from seaweed and contains calcium alginate.14 The packing provides hemostasis, has healing properties, and is atraumatically inserted and removed. Hydration with normal saline activates the calcium alginate and makes it pliable. The packing expands 300% and conforms to the anterior nasal cavity. It activates platelet aggregation to provide hemostasis, keeps the nasal mucosa moist, and gels into a smooth surface that allows easy removal. Prepare the packing. The ENTaxis is packaged in a plastic tray with a tear-off paper lid. Peel the lid completely off the tray. Fill the tray with normal saline to saturate the packing. Remove the hydrated packing from the tray. Squeeze out the excess saline from the packing. Insert a nasal speculum. Grasp the packing on the end opposite the string with a bayonet forceps. Insert the packing along the floor of the nasal cavity. Continue to insert the packing in an accordionlike fashion until the entire packing is within the nasal cavity. The packing will expand and gel to fill the nasal cavity. Secure the string to the patient’s cheek or nose with a piece of tape. Removal of the packing is simple and quick. The packing remains hydrated and in a gelled state while within the nasal cavity. Place a kidney basin under the patient’s nose. Untape the string from the patient’s face. Grasp the packing with a bayonet forceps. Gently withdraw the packing from the nasal cavity.
THROMBIN-JMI THROMBIN-JMI Epistaxis Kit (Pfizer Pharmaceuticals, New York, NY) is a topical bovine thrombin approved for the management of epistaxis. It works on sites of minor bleeding and oozing. The thrombin causes fibrinogen in the blood to clot without the requirement of
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platelet activation. The kit contains one vial of thrombin, one vial of diluent, a needle and syringe, and a nasal delivery device. Open the outer packaging to reveal a sterile inner tray with the kit components. Use the syringe with the needle to draw up the saline diluent. Inject the saline diluent into the THROMBIN-JMI vial. Gently swirl the vial to mix the components and reconstitute the thrombin powder. When completely dissolved, draw the thrombin solution into the syringe. Remove the needle from the syringe and attach the nasal delivery device. Insert the nasal delivery device into the nares. Depress the plunger to spray the thrombin solution onto the nasal mucosa. Remove the device. Allow the solution to form a clot. Apply additional thrombin solution if the bleeding continues. Consider applying a piece of Gelfoam to the newly formed clot to support it.
FLOSEAL The Floseal Hemostatic Matrix (Baxter Healthcare Corporation, Hayward, CA) is composed of human-derived thrombin and bovine-derived gelatin. It stops bleeding fast and in up to 97% of cases.15 The thrombin–gelatin matrix begins to break down in 3 to 5 days and is gone by 7 days. Floseal does not require platelet activation, allowing it to function in patients taking aspirin and other antiplatelet medications. Floseal is provided in components that must be mixed. The process is more complicated than other thrombin products and can take several minutes. The kit contains all of the required components and supplies. Use the 5 mL syringe and attached needle to draw up the calcium chloride solution. Inject the calcium chloride solution into the lyophilized thrombin vial. Gently swirl the vial to mix the components and reconstitute the thrombin. Draw up the thrombin solution into the syringe. Gently transfer it into the bowl in the kit. Use the empty 5 mL syringe with a female Luer lock to aspirate the thrombin solution from the bowl into the syringe. Connect this syringe to the syringe containing the gelatin matrix granules. Push the plunger to fully transfer the thrombin solution into the gelatin containing syringe. This is considered “one pass.” Transfer the gelatin–thrombin solution back and forth between the syringes for at least 20 passes. Disconnect the syringes. Attach one of the two applicator tips to the syringe containing the gelatin–thrombin solution. Apply a small mound of the Floseal to the bleeding source. The Floseal must remain at the site for 2 minutes. Place a sterile salinemoistened gauze sponge over the Floseal mound to ensure it maintains a seal against the bleeding site. After 2 minutes, remove the gauze and inspect the site. If the gauze adheres to the clot or the Floseal, moisten it with sterile normal saline. If bleeding persists, insert the applicator tip through the Floseal mound and deliver fresh Floseal to the bleeding site. Remove any excess Floseal by gentle irrigation after the bleeding is controlled. Consider applying a piece of Gelfoam to the newly formed clot to support it.
WOUNDSEAL WoundSeal for Nosebleeds (Biolife LLC, Sarasota, FL) was previously marketed as NoseBleed QR. It is an over-the-counter product that comes in a variety of applications to control bleeding. It is marketed to control epistaxis and external wounds of all types. It consists of a powder containing a hydrophilic polymer and potassium ferrate. When the powder comes in contact with blood, the polymer absorbs liquid and concentrates the red blood cells and plasma proteins under the powder to form a clot. The potassium ferrate releases iron to bind the blood proteins into a clot. The WoundSeal powder is simple to apply. Open the blister pack. Roll the tip of the applicator stick in the powder to completely coat
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it. Roll the powder coated applicator onto the nasal mucosa. Remove the applicator stick from the nasal cavity. Pinch the nostrils closed for 30 seconds. Reassess the nasal cavity for continued bleeding and the need for additional applications of the powder. Consider applying a piece of Gelfoam to the newly formed clot to support it.
ANKAFERD BLOOD STOPPER Ankaferd Blood Stopper (ABS, Ankaferd Health Products LTD, Istanbul, Turkey) is a medicinal plant extract. It is approved in Turkey for the management of postsurgical dental bleeding and external hemorrhage.16 ABS is not currently available in the United States and most other countries. It induces the rapid formation of a hemostatic protein network to control hemorrhage that is not dependent upon coagulation factors and platelets.16 It has been successfully used to control epistaxis.17 ABS may provide a new method to control epistaxis in the future.
POSTERIOR EPISTAXIS MANAGEMENT TECHNIQUES A posterior source of the bleeding must be sought when epistaxis is bilateral, brisk, and not controlled with anterior nasal packing. It is estimated that 5% of all cases of epistaxis originate from a posterior source.18 The placement of a posterior nasal pack is
extremely uncomfortable. The patient may require, on some occasions, intravenous sedation and analgesia in addition to the topical anesthesia previously described. Consider spraying the patient’s soft palate, uvula, and oropharynx with a topical anesthetic spray (e.g., Cetacaine). This will minimize their gag reflex during the placement of the posterior pack. The rationale behind placing a posterior pack is that the occlusion of the choanal arch provides a semirigid buttress against which anterior nasal packing may be placed, allowing adequate hemostasis to be achieved. This buttress may be formed from either a gauze pack, a 30 mL Foley catheter, an expandable nasal sponge/tampon, or an inflatable nasal balloon catheter. From a practical standpoint, the Foley catheter and inflatable nasal balloon catheter are most easily tolerated by the patient. The inflatable nasal balloon catheter is definitely the easiest to place, as it has two balloons that serve as both anterior and posterior packs. An anterior nasal pack is always required on the side of a posterior pack. Strongly consider inserting a contralateral anterior nasal pack to maintain the septum in the midline.
TRADITIONAL (GAUZE ROLL) PACKING The traditional technique of posterior nasal packing involves using rolled gauze, dental rolls, or tonsil packs placed through the oropharynx (Figure 172-9). This technique is difficult, time-consuming,
FIGURE 172-9. The traditional technique of placing a posterior nasal pack. A. Preparation of the pack. B. A red rubber catheter inserted through the nostril and pulled out the mouth. C. The pack is attached to the two red rubber catheters. D. The pack is pulled into place. Use a finger to pass the pack around the soft palate and uvula. E. An anterior nasal pack has been placed. F. The ties of the posterior pack are secured.
CHAPTER 172: Epistaxis Management
messy, requires many supplies, and is not well tolerated by the patient. Easier and quicker techniques exist. For these reasons, this technique is not often performed. Prepare the equipment. Gather the required equipment on a bedside procedure table. Use 3 inch long dental rolls or tonsil packs. An alternative is to use 3 inch wide and 36 inch long petrolatum gauze. Form a tight cylindrical roll with the gauze (Figure 172-9A). Tie two pieces of umbilical tape or 0 silk suture around the pack to divide it into thirds (Figure 172-9A). Anesthetize and vasoconstrict both nasal cavities. Apply a topical anesthetic spray to the soft palate, uvula, and oropharynx. Lubricate a red rubber catheter. Pass the red rubber catheter through one nostril and along the floor of the nasal cavity. Advance the catheter so that the tip is visible in the patient’s oropharynx. Grasp the tip of the catheter with a hemostat or forceps and pull it out the patient’s mouth (Figure 172-9B). Clamp the free ends of the catheter together. Pass a second red rubber catheter through the other nostril and out the patient’s mouth. Insert the posterior pack. Tie the free end of one piece of the umbilical tape or silk surrounding the packing to the distal end of one red rubber catheter exiting the patient’s mouth (Figure 172-9C). Tie the knots tightly. Tie the second piece of umbilical tape or silk to the second red rubber catheter. Pull the proximal ends (i.e., the portion exiting the nostrils) of both red rubber catheters until the packing is against the choanae (Figure 172-9D). It may be necessary to place a finger into the patient’s mouth and push the pack behind the soft palate and uvula if it gets caught (Figure 172-9D). Place a hemostat on both pieces of umbilical tape exiting the nostrils. Apply slight traction with the hemostat to maintain the posterior pack against the choanae. Instruct an assistant or the patient to hold the hemostat. Untie or cut the red rubber catheters from the umbilical tape or silk sutures. Place an anterior pack and secure the posterior pack. An anterior nasal pack is always required when placing a posterior nasal pack. The anterior pack may be an expandable sponge/tampon, petrolatum gauze, or a balloon catheter (Figure 172-9E). Tie the umbilical tape or silk exiting each nostril together (Figure 172-9F). Always place a piece of cotton or gauze between the knot and the columella to prevent pressure necrosis (Figure 172-9F). Tie the umbilical tape or silk snugly but not too tight to hold the posterior pack in place and not apply pressure to the choanae or the columella. Tape the umbilical tape or silk exiting the patient’s nostril and mouth to their face (Figure 172-9F).
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Removal of this packing is simple and requires several stages. Remove the anterior packing. Thoroughly examine the mucosa to make sure that the epistaxis has not restarted. Suction any clots and blood from the nasal cavity. Rebleeding requires the placement of a new anterior pack if it cannot be controlled with an absorbable dressing or silver nitrate. Cut the knot, securing the umbilical tape or silk around the columella. Pull the pieces of umbilical tape or silk exiting the patient’s mouth to remove the posterior pack completely.
FOLEY CATHETER TECHNIQUE A Foley catheter may be used to provide a posterior buttress. Using a Foley catheter is easy, quick, and simple. Select a 14 French Foley catheter with a 30 mL balloon. Inflate the balloon with air. Ensure the integrity of the balloon. Some Emergency Physicians cut off the portion of the Foley catheter distal to the balloon. They believe that the distal tip is irritating to the patient and may stimulate their gag reflex. The practice of cutting off the distal tip is based purely on Emergency Physician preference. Be careful to not cut the balloon or its attachment to the catheter. Lubricate the distal third of the Foley catheter. Insert the Foley catheter into the nostril and along the floor of the nasal cavity. Advance the catheter until the tip is visible in the patient’s oropharynx. Inflate the balloon with 7 to 10 mL of air. Do not use saline, as the fluid can result in aspiration if the balloon ruptures. Withdraw the catheter to lodge the balloon against the choanal arch (Figure 172-10A). If the balloon withdraws into the nasal cavity, advance it back into the nasopharynx. Add an additional 3 to 5 mL of air and withdraw the catheter. Continue the process by adding 3 to 5 mL aliquots of air until the balloon lodges against the choanal arch. Inflate the balloon with an additional 3 to 5 mL of air and the soft palate just begins to bulge. The balloon is overinflated if the soft palate bulges or the patient experiences pain. Place an anterior pack and secure the Foley catheter. Apply slight traction to maintain the balloon against the choanal arch. Instruct an assistant or the patient to hold the Foley catheter. Place the anterior pack using an expandable sponge/tampon, petrolatum gauze, or a balloon catheter. Place a piece of cotton or gauze against the columella and nasal ala to prevent pressure necrosis.19 Place an umbilical clamp on the Foley catheter and over the protective padding (Figure 172-10B). The clamp must hold the
FIGURE 172-10. The Foley catheter technique. Insert a Foley catheter along the floor of the nasal cavity until the tip is visible in the patient’s oropharynx. A. Inflate the balloon and withdraw the catheter to lodge the balloon against the choanal arch. B. Secure the Foley catheter.
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balloon against the choanal arch without applying pressure to the choana or columella. Removal of this packing is simple and requires several stages. Cut the open loop of the umbilical clamp with a scissors. Open the jaws of the clamp and remove them from the Foley catheter. Always maintain a grasp of the catheter and apply slight traction to keep the balloon in place. Remove the anterior packing. Thoroughly examine the mucosa to make sure that the epistaxis has not restarted. Suction any clots and blood from the nasal cavity. Rebleeding requires the placement of a new anterior pack if it cannot be controlled with an absorbable dressing or silver nitrate. Deflate the balloon and pull the catheter out the patient’s nostril.
EXPANDABLE NASAL SPONGES/TAMPONS Many Emergency Physicians prefer to use an 8 or 10 cm sponge/ tampon rather than the other techniques of posterior packing. This technique is easy, quick, simple, and inexpensive. The technique for insertion and removal is exactly the same as for the anterior packing technique described previously. The Epistat II (Medtronic Xomed Inc., Jacksonville, FL) is a combination device with an anterior nasal sponge/tampon and a posterior balloon. It provides better posterior hemostasis than a sponge/tampon alone.
INFLATABLE NASAL BALLOON CATHETERS A dual-balloon catheter can be used when a posterior pack is required. These catheters come in many types and styles (Figure 172-6). They are expensive but easy to use and quickly placed. The smaller distal balloon obstructs the choanal arch and acts as a posterior pack (Figure 172-11). The larger proximal balloon fills the nasal cavity and acts as an anterior pack (Figure 172-11). The distal balloon holds 10 mL and the anterior balloon holds 30 mL in most dual-balloon systems. Note the manufacturer’s maximum volume recommendations on the package and on the inflation ports of the balloons. Prepare the equipment. Fully inflate both balloons with air. Observe and palpate the balloons for leaks. They may also be inflated in a cup of water to look for leaks. Completely deflate both balloons. Apply a lubricant over the catheter and balloons. Insert the catheter with the distal bevel toward the nasal septum. This prevents the distal end of the catheter from getting
caught on the turbinates, damaging the mucosa overlying the turbinates, and causing a second source of epistaxis. Advance the catheter along the floor of the nasal cavity until the distal tip is visible in the patient’s oropharynx. Inflate the distal balloon with 4 to 5 mL of air. Do not use saline or water to inflate the balloon. Rupture of the balloon can result in aspiration if it is filled with liquid. Withdraw the catheter to lodge the balloon against the choanal arch (Figure 172-11). If the balloon withdraws into the nasal cavity, advance it back into the nasopharynx. Add an additional 2 to 3 mL of air and withdraw the catheter. Continue this process until the balloon lodges or the maximum balloon volume is reached. Inflate the anterior balloon with 20 to 25 mL of air. Observe the patient for bleeding. Inflate both balloons with additional aliquots of air until the bleeding stops or the maximum balloon volume is reached. The balloon does not always fill the high anterior nasal cavity. Deflate the anterior balloon, pack the high anterior nasal cavity with Vaseline gauze, and reinflate the anterior balloon. Place an anterior pack contralaterally if the bleeding continues to maintain the septum in the midline and apply pressure to the ipsilateral nasal cavity.
SPHENOPALATINE ARTERY BLOCK This technique is a last resort when an Otolaryngologist is not available, the hemorrhage is unremitting, and other methods to control the hemorrhage have failed. Local anesthetic solution is injected into the pterygopalatine canal to occlude the sphenopalatine artery. The local anesthetic solution can cause pressure necrosis of the adjacent nerves within the bony canal. Place the patient supine with their mouth open. Apply a topical anesthetic spray to the hard palate. Identify the greater palatine foramen. Insert a 27 gauge needle into the mucosa of the hard palate, 1 cm medial to the gum line between the junction of the second and third maxillary molars. Probe this area with the needle until it falls into the greater palatine foramen. Inject 0.25 mL of local anesthetic solution containing epinephrine into the mucosa overlying the greater palatine foramen. Arm a 3 or 5 mL syringe containing local anesthetic solution with epinephrine with a 22 or 25 gauge needle. Insert the needle approximately 25 to 28 mm into the greater palatine foramen. Inject 3 mL of the local anesthetic solution.
SURGICAL INTERVENTION Consult an Otolaryngologist when the epistaxis is difficult to control by the described methods, as surgical intervention is then indicated. Surgical therapy may include septoplasty, endoscopic cauterization, arterial ligation (internal maxillary artery, sphenopalatine artery, anterior and posterior ethmoid arteries, external carotid artery), or embolization.20
PEDIATRIC CONSIDERATIONS
FIGURE 172-11. Placement of a dual-balloon catheter.
Epistaxis is a common childhood symptom that may prompt an evaluation in the Emergency Department. Generally, the management of a child with acute epistaxis is straightforward. The source of bleeding is from the anterior one-third of the nasal septum, just posterior to the squamous-mucosal junction in the majority of children. The etiology is often due to digital manipulation, infection, allergic rhinitis, a coagulopathy, a foreign body, trauma, medications, a neoplasm, and surgery. The principles of management in the pediatric population are similar to those of adult patients. Active bleeding requires immediate attention. The child needs to be assessed for any hemodynamic instability or airway compromise. A brief history should be
CHAPTER 173: Laryngoscopy
obtained during the initial stages of treatment. The minimal equipment required for initial evaluation includes a headlight, Yankauer suction, Frazier tip suction, a small nasal speculum, and a tongue depressor. Additional supplies may be required, as well. A more comprehensive list of equipment and medications has been outlined earlier in this chapter. After managing any life-threatening injuries and ensuring hemodynamic stability, the goal is to identify the bleeding source. Apply an anesthetic and vasoconstrictor. Evacuate any remaining clot from the nasal airway and inspect the mucosa. If the bleeding source is identified, the vessel should be cauterized with silver nitrate. Once the mucosa has been cauterized, apply a thin piece of oxidized cellulose (i.e., Surgicel) or Gelfoam that has been impregnated with an antibiotic ointment over the site to help stabilize the clot. Place an anterior nasal pack if chemical cauterization fails to control the bleeding. Expandable nasal sponges/tampons are readily available and are relatively easy to place. Trim the sponge/tampon to an appropriate length prior to insertion. Consult an Otolaryngologist if the bleeding cannot be controlled, if there are concerns that the bleeding source is from a posterior location, and for any postsurgical patient. Once the presenting symptoms have been addressed, the underlying cause should be identified and treated. For patients with epistaxis secondary to digital manipulation, antibiotics ointment and nasal saline should be used to minimize crusting and to hydrate the mucosa. Antibiotic therapy is indicated in cases of acute sinusitis and adenoiditis. Coagulopathy must be considered when a patient presents with recurrent epistaxis. Sandoval et al found that 30% of children who presented with recurrent epistaxis had a diagnosable coagulopathy.21 Von Willebrand’s disease was noted to be the most common disorder identified. Serology should include a CBC, PT, PTT, and INR in patients whose history suggests heavy bleeding, recurrent bleeding, or a personal or family history of bleeding abnormalities.
AFTERCARE The postprocedural care of patients with anterior epistaxis is just as important as the initial control of bleeding. All patients with nasal packing require prophylactic oral antibiotic therapy with adequate coverage for Staphylococcus aureus, Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis. This is due to the significant risk of developing sinusitis and toxic shock syndrome. Arrange follow-up with an Otolaryngologist within 24 to 48 hours. Remove the packing in 48 to 72 hours if the patient experienced only minimal blood loss and was hemodynamically stable. Inform the patient that the anterior pack is “uncomfortable.” Acetaminophen will provide any required analgesia. Avoid aspirin containing compounds and nonsteroidal anti-inflammatory drugs, as they can contribute to further bleeding. Instruct the patient to apply saline nasal spray to the packing or each nostril three or four times per hour while awake. The use of a humidifier at home will aid in preventing drying of the packing or the nasal mucosa. The patient must avoid nose picking and nose blowing. Instruct the patient on the proper technique to apply pressure on the nose if bleeding restarts. Such pressure should be maintained for 20 minutes. Continued bleeding calls for a return to the Emergency Department. The patient should also return for increased nasal pain, fever, or any symptoms related to blood loss (e.g., chest pain, dyspnea on exertion, dizziness, light-headedness, presyncope, shortness of breath, and syncope). Patients with unstable vital signs, uncontrollable bleeding, posterior packing, or serious concomitant medical problems will require hospitalization. Patients with posterior nasal packs require consultation with an Otolaryngologist and admission to a telemetry or
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intensive care unit. They must be monitored for respiratory distress, hypoxia, hypotension, anemia, and cardiac sequelae. It has been estimated that 40% of patients with posterior nasal packing eventually require intubation.18 The nasal ala and columella must be evaluated continually in order to prevent pressure necrosis. Patients with a posterior nasal pack may experience hypoxemia and hypercarbia. The etiology of these phenomena, called the nasopulmonary reflex, is unknown. The PaO2 may decrease 7.5 to 15 mmHg. The PaCO2 may increase 7 to 15 mmHg. The nasopulmonary reflex is more worrisome in patients with underlying lung disease or comorbid conditions.
COMPLICATIONS The complications associated with epistaxis are variable, wideranging, and estimated to be from 2% to 69%.22 Epistaxis may be complicated by hemorrhage, hypoxemia, hypovolemia, circulatory collapse, and airway compromise. Complications resulting from the treatment of epistaxis include nasal septal perforation, sinusitis, otitis media, toxic shock syndrome, aspiration, alar necrosis, and hypoxia from intrapulmonary shunting due to the stimulation of the nasopulmonary reflex.23 The majority of complications can be prevented by using proper technique, providing supplemental oxygen when not contraindicated, ordering appropriate prophylactic antibiotics, arranging appropriate hospitalization if indicated, obtaining an Otolaryngology consultation, and arranging for adequate follow-up.
SUMMARY Epistaxis is a common condition that affects 10% to 13% of the general population. The key to successful management includes a prompt and thorough evaluation of the patient, an accurate diagnosis of the problem, and rapid control of the bleeding. Ninety percent of cases of epistaxis stem from an anterior source and can be controlled with either chemical cautery or nasal packing. Posterior bleeding requires the use of both a posterior pack and anterior packing. All patients with nasal packing require prophylactic antibiotics to prevent sinusitis and toxic shock syndrome. Follow-up is required in 24 to 72 hours with an Otolaryngologist or the Emergency Department to remove the nasal packing.
173
Laryngoscopy Steven Charous
INTRODUCTION Evaluation of the larynx can be crucial in the diagnosis and management of common and life-threatening disorders. The approach to the patient with laryngeal dysfunction begins with obtaining a complete history. Symptoms may be related to any of the three primary functions of the larynx. These are protection of the lower airway from aspiration, a conduit of the airway, and phonation. Symptoms may include aspiration, cough, dysphagia, odynophagia, dyspnea, or hoarseness. Otalgia may be a referred symptom from the larynx and transmitted by a branch of the vagus nerve. Information regarding patient age, onset, duration, severity, and progressive nature of the process is necessary. Determine the patient’s past medical history including prior intubations, neck trauma, reflux esophagitis, similar previous episodes, and other
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TABLE 173-1 Summary of the Advantages and Disadvantages of the Different Techniques used to Perform Indirect Laryngoscopy Handheld mirror Per-oral flexible endoscopy Per-oral rigid endoscopy Nasal flexible endoscopy Gag reflex Moderate Moderate Moderate Minimal Visual clarity Good Good–distorted Superior Good–distorted Anesthesia required Occasionally Yes Occasionally Yes Observe larynx during speech No No No Yes Patient cooperation Necessary Necessary Necessary Not necessary Approximate equipment cost Minimal $4500 $4500 $4500 Photodocumentation possible No Yes Yes Yes
systemic diseases. The social history, including smoking and alcohol usage, needs to be investigated. Medications, allergies, and over-the-counter drugs should be reviewed. Perform a physical examination, including a complete head and neck examination, once the history has been obtained.1 Listen for stridor and watch for accessory muscle breathing. Consciously and critically evaluate the patient’s voice to hear breathiness, clarity, and volume. Inspect the ears, nose, oral cavity, oropharynx, and nasopharynx. Careful palpation of the neck is extremely important. Note any lymphadenopathy and neck masses. This must include their size, location, tenderness, and mobility. Palpate the larynx and note any crepitus (the lack of crepitus on lateral movement of the larynx over the vertebral bodies can be indicative of a laryngeal or hypopharyngeal mass), movement with swallowing, and asymmetry. This can help in determining the extent of a disease process. Visualize the larynx after performing a complete history and physical examination, with the exception of true airway emergencies. This allows the Emergency Physician to examine the larynx in context to the patient’s symptoms and other physical findings. It also allows a rapport to develop between the patient and Emergency Physician prior to undergoing a mildly invasive procedure. There are four methods of performing indirect laryngoscopy: mirror laryngoscopy, nasal flexible fiberoptic laryngoscopy, oral flexible fiberoptic laryngoscopy, and rigid telescopic laryngoscopy. The following is a complete description of the procedure involved in performing each of these techniques. An excellent pictorial source for viewing normal and pathological conditions of the larynx may be found in Bruce Benjamin’s Diagnostic Laryngoscopy: Adults and Children.2 Table 173-1 reviews the advantages and disadvantages of each procedure. Each method allows visualization of the larynx with different degrees of distortion (Figure 173-1).
A
B
ANATOMY AND PATHOPHYSIOLOGY The larynx occupies the central neck and is located within the hypopharynx3,4 (Figures 173-2 & 173-3). Lateral to the larynx are the pyriform sinuses, the pharyngeal recesses that are the primary route for food to pass into the esophagus. The basic framework of the larynx consists of the thyroid cartilage, cricoid cartilage, epiglottic cartilage, arytenoid cartilage, and the hyoid bone. The shield-like thyroid cartilage supports the soft tissues of the larynx. It is connected to the hyoid bone via the thyrohyoid membrane and is attached to the cricoid cartilage via the cricothyroid membrane and at the cricothyroid joint. The signet ring-shaped cricoid cartilage is the only complete cartilaginous ring in the larynx. On top of its posterior portion sits the paired arytenoid cartilages. The arytenoid cartilages are somewhat shaped like an inverted “T.” Each has a body, a muscular process, and a vocal process. The aryepiglottic folds connect the epiglottis to the top portion of the arytenoid body. The vocal ligament attaches the vocal process to the thyroid cartilage. The cricoarytenoid muscles attach to the
C FIGURE 173-1. Visualization through the endoscopes. A. Endoscopic view through the 90° rigid telescope. Note the magnification, clarity, and breadth of view. B. Endoscopic view through flexible fiberoptic scope. Note the distortion and limited view as compared to the view through the rigid scope. C. Endoscopic view through the “chip-in-tip” scope. Note the larger field of vision with minimal distortion.
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A Hyoid bone Thyrohyoid membrane Epiglottis Vocal ligament
Arytenoid cartilage
Cricothyroid ligament or membrane Cricoid cartilage
A
B Hyoid bone
Epiglottis Thyrohyoid membrane
Vocal ligament
Thyroid cartilage
Arytenoid cartilage
Cricoid cartilage
FIGURE 173-2. The laryngeal framework. A. Lateral view. B. Superior view.
muscular process. The epiglottic cartilage is leaf-shaped and forms the anterior wall of the laryngeal entranceway. Its main portion projects posterior to the tongue base. It folds downward over the larynx during swallowing to aid in protecting the laryngeal opening from aspiration. The muscles associated with the larynx may be divided into extrinsic muscles and intrinsic muscles. The extrinsic muscles move the larynx as a unit and can be further subdivided into those muscles that elevate the larynx (stylohyoid, digastric, geniohyoid, and stylopharyngeus) and those that depress the larynx (omohyoid, sternohyoid, and sternothyroid). The intrinsic muscles are involved with vocal cord mobility and all cause adduction with the exception of the cricoarytenoid muscle that causes abduction. Innervation to the intrinsic laryngeal muscles is via the recurrent laryngeal nerve, a branch of the vagus nerve (cranial nerve X). The cricothyroid muscle is the only muscle innervated by the external branch of the superior laryngeal nerve, a branch of the vagus nerve. All of the laryngeal muscles and cartilages are covered with respiratory epithelium. Just superior to the vocal cords is a recess called the laryngeal ventricle. Just superior to the ventricle are the false vocal folds. These are rounded protrusions rich in mucous secreting glands. The supraglottic larynx is defined as that portion of the larynx extending from the tip of the epiglottis to the laryngeal ventricle. The glottic larynx contains the true vocal cords and extends approximately 5 to 7 mm inferiorly. The subglottis extends from the inferior glottis to the inferior edge of the cricoid cartilage.
B FIGURE 173-3. Endoscopic view of the laryngeal anatomy. A. Vocal cords open. B. Vocal cords closed.
The primary function of the larynx is to protect the airway from the aspiration of food particles. A complex reflex arc, with the glossopharyngeal nerve (cranial nerve IX) mediating the sensory arm and the vagus nerve (cranial nerve X) mediating the motor arm, occurs with swallowing. With each swallow the larynx elevates, the aryepiglottic folds squeeze medially, the epiglottis folds posteriorly over the larynx, and the true and false vocal folds close tightly. This allows the food bolus to pass around the larynx, into the pyriform sinuses, and subsequently into the esophagus. Any alteration or disturbance in the reflex arc may predispose a patient to aspiration. Phonation occurs with adduction of the vocal cords as air passes from the trachea through the vocal cords. The mucosa overlying the muscles of the vocal cords undulates and the two vibrating vocal cords produce sound. Anything that alters the mucosal wave of the vocal cords, impairs adduction, or changes the configuration of vocal cord alignment will result in decreased phonatory performance. Note that mucosal wave abnormalities can only be observed with videostroboscopy of the larynx. Many things can change a person’s voice. This includes inflammation, thick mucous, vocal cord
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paralysis, and tumors. Be careful and define hoarseness as a change in the patient’s vocal quality. What may be normal for one patient may not be for another. The larynx is crucial in respiratory activity. Inspiration signals the recurrent laryngeal nerve to stimulate vocal cord abduction. Impairment in abduction, unilaterally or bilaterally, can lead to respiratory compromise.
INDICATIONS Have a very low threshold for examining the larynx. The diagnostic value of laryngoscopy greatly outweighs the minimal discomfort associated with the quick procedure. Any patient presenting with an allergic reaction, angioedema, acute hoarseness or voice changes, symptoms of aspiration, shortness of breath, a foreign body sensation, hemoptysis, stridor, exposure to ingested caustic agents, exposure to hot fumes or gasses, exposure to caustic fumes or gasses, or any other symptom that may be related to the larynx should have laryngoscopy performed as part of a complete physical examination.
CONTRAINDICATIONS There are no absolute contraindications for laryngoscopy. Patients with severe respiratory compromise, such as a child with suspected epiglottitis, should have laryngoscopy performed in the Operating Room (or in a controlled area) with an Anesthesiologist, intubation equipment, and tracheotomy instrumentation ready for use. Performing laryngoscopy in the respiratory distressed patient can lead to increased distress and ventilatory collapse if laryngospasm ensues. Use caution when performing laryngoscopy in a patient with a high-grade airway obstruction, a supraglottic expanding hematoma, or significant laryngeal trauma. In general, the patient must be able to follow instructions and cooperate with the examination.
EQUIPMENT Anesthesia and Vasoconstriction • 10% lidocaine spray • 20% benzocaine spray • 2% tetracaine spray • 4% cocaine • 3% ephedrine or Neo-Synephrine spray • Cotton pledgets Scopes • #4 or #5 dental mirror, with or without magnification • 3 to 5 mm diameter flexible fiberoptic laryngoscope; 3 mm is better for children • 90° rigid laryngoscope Light Sources • Headlight for mirror examinations • 125 to 250 watt halogen or xenon light sources for fiberoptic laryngoscopes Miscellaneous • Alcohol lamp, heated beads, or glass of warm water for mirror examination • 4 × 4 gauze squares • Water-soluble lubricant • Antifog solution • Video camera and equipment for teaching and photodocumentation, optional
FIGURE 173-4. Basic equipment required for examination of the larynx in the ambulatory setting. Included are the rigid 90° telescope, dental mirror, flexible fiberoptic scope, gauze, oral anesthetic, antifog solution, and a light source. Not included is topical spray for nasal decongestion and anesthesia.
Set up all of the required equipment on a bedside procedure table (Figure 173-4). Prepare several different endoscopes, if available. If one fails, or is inadequate, another will be immediately available. The availability of multiple endoscopes allows the Emergency Physician to choose the scope and technique of their choice. The flexible fiberoptic scopes are comprised of fiberoptic strands and lenses along its length. Do not manipulate or bend it into acute angles. Do not place objects onto the scope. Do not use abrasive materials (i.e., gauze, paper towels) to wipe the lens at the end of the fiberoptic cord.
PATIENT PREPARATION Explain the risks, benefits, and potential complications of the procedure to the patient and/or their representative. Patient reassurance and relaxation is of the utmost importance in obtaining excellent visualization of the larynx. This can be achieved by reviewing what can be expected from the patient’s perspective, by reassuring them of the minimal discomfort, and by reassuring them of the short duration of the procedure. Patient positioning is crucial in obtaining laryngeal visualization in any per-oral technique. Place the patient sitting upright in a multipositional procedure chair or on a gurney with their legs together. Instruct the patient to lean slightly forward and to draw their chin forward. This aligns the larynx and the oropharynx in a vertical plane to allow visualization of the anterior portion of the larynx. Raise or lower the multipositional chair, or the gurney, so that the patient’s mouth is at the examiner’s eye level. Patient cooperation and positioning is not crucial for flexible fiberoptic examination of the larynx performed through the nose. Place the patient, optimally, sitting upright with their head against a headrest. The headrest will prevent the common occurrence of the patient’s head backing away during the examination. The examination with the patient in the supine position is technically more challenging as gravity pushes the tongue posteriorly and the scope falls against the posterior pharyngeal wall; both of which make visualization of the anteriorly placed larynx more difficult. However, in most instances, it can still be performed without significant problems.
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The use of good lighting cannot be overemphasized when performing a mirror examination. Apply a headlamp if one is available. An alternative is an overhead adjustable light source. Position the light so that it is aimed in the patient’s mouth. The overhead light often hits the examiner in the head, casts shadows, and is too bright for the patient’s eyes. It is also difficult to properly position as both of the examiner’s hands must be used for the procedure.
TECHNIQUES THE MIRROR EXAMINATION
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Introduce the mirror into the oral cavity with the glass surface parallel to the tongue (Figure 173-5). Instruct the patient to say a high-pitched “e-e-e” and hold it for 5 seconds just before the mirror touches and elevates the uvula and soft palate. The high-pitched “e-e-e” tilts the epiglottis forward and brings the vocal cords into view and apposition. Inform the patient that the “e-e-e” may sound like “ahhhhhh” while their tongue is held. This is helpful to them as they try to cooperate fully with the instructions. The Emergency Physician should simultaneously demonstrate the high-pitched sound as patients invariably will phonate in too low of a pitch for too short of a time period. Prevent gagging by asking the patient to phonate before the mirror actually touches the soft palate, avoiding touching the base of the tongue, and avoid touching the anterior tonsillar pillars. Focus the headlight (or overhead light), as the patient phonates, on the mirror. Gently and slightly maneuver the mirror until the larynx is visualized. Remember the orientation through the mirror. Left and right are the same but anterior and posterior have reversed orientation. Perform a quick and systematic evaluation of the larynx and hypopharynx. Assess the airway structures including the base of the tongue, vallecula, epiglottis, aryepiglottic folds, true and false vocal cords, arytenoids, posterior pharyngeal wall, and pyriform sinuses. Visualize adduction and abduction of the vocal cords during phonations and inspirations. Several reinsertions of the mirror are often required to obtain a complete examination.
Determine whether the patient has a significant gag reflex. If so, apply topical anesthesia. Spray a topical local anesthetic agent (e.g., benzocaine, lidocaine, or tetracaine) onto the patient’s palate, tonsillar pillars, posterior pharyngeal wall, and base of the tongue. The application of a topical anesthetic agent is optional if the patient does not have a significant gag reflex. Instruct the patient to keep their eyes open and focus on a distant object to diminish the gag reflex. Practicing the entire procedure once with the patient, without inserting the mirror, is often a more reassuring and efficient manner of performing indirect laryngoscopy. Instruct the patient to protrude their tongue. Grasp the tongue firmly, between the nondominant thumb and index finger, with a neatly folded gauze square (Figure 173-5). Do not apply excessive traction on the tongue. This is counterproductive as it elevates the tongue and makes the patient uncomfortable. Place the nondominant middle finger against the upper teeth as a brace. It may also be used to elevate the upper lip if needed. Instruct the patient to breathe through their mouth in a slow “panting-like” manner and to try to relax their tongue. This maneuver diminishes the gag reflex, elevates the palate, and lowers the tongue giving better access and visualization of the oropharynx. Warm the mirror over an alcohol lamp, in heated beads, or in a cup of warm water to prevent fogging during the examination. Test the mirror back, if any type of heat is used, on the examiner’s wrist for excessive heat that can injure the patient. An alternative is to use a mirror that has antifog solution placed on it to prevent fogging during the examination. Grasp the mirror with the dominant hand midway down the shaft like a pen (Figure 173-5). Brace the dominant fifth finger against the patient’s face.
The examiner will often have a more leisurely view of the larynx with this technique, as compared to the mirror exam. Patients usually gag less and can tolerate this examination for longer periods of time. Position the patient the same as for the mirror examination. All patients undergoing this procedure, in contrast to the mirror examination, must be topically anesthetized with an aerosolized local anesthetic agent as described above. Connect the light source to the fiberoptic scope and turn it on. Turn off the overhead room lights, if possible, to provide better contrast. Instruct the patient to protrude their tongue and to grasp it with a gauze square (Figure 173-6). Hold the eyepiece of the scope in the dominant hand. Use the dominant thumb to manipulate the
FIGURE 173-5. Proper positioning for an indirect mirror examination of the larynx. Both of the examiner’s hands should be braced against the patient for stability once the mirror is positioned in the oropharynx.
FIGURE 173-6. Positioning for an oral flexible fiberoptic examination of the larynx. The patient grasps their tongue with a gauze square. The examiner’s left hand is braced against the patient’s face.
PER-ORAL FLEXIBLE FIBEROPTIC LARYNGOSCOPY
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tip controller. Grasp and hold the middle portion of the fiberoptic scope with the thumb and index finger of the nondominant hand. Brace the remaining fingers of the nondominant hand against the patient’s face (Figure 173-6). Instruct the patient to breathe slowly through their mouth in a “panting-like” manner. Advance the scope with both hands until the tip is situated within the middle of the mouth and over the base of the tongue. Use the hand control to direct the tip of the scope downward. Look through the scope and visualize the base of the tongue, the vallecula, and the tip of the epiglottis. Direct the scope posteriorly over the epiglottis. The larynx and hypopharynx will come into view (Figure 173-3). Adjust the eyepiece, if necessary, to focus the scope. Avoid touching the epiglottis as this may induce gagging. Entry into the laryngeal vestibule will allow a more detailed examination, but may also induce laryngospasm if the vocal cords are touched. Perform a systematic examination of the laryngeal and hypopharyngeal anatomy. Instruct the patient to say “e-e-e” while viewing abduction and adduction of the vocal cords.
PER-ORAL RIGID FIBEROPTIC LARYNGOSCOPY Position the patient the same as for the mirror examination. All patients undergoing this procedure, in contrast to the mirror examination, must be topically anesthetized with an aerosolized local anesthetic agent as described above. Connect the light source to the fiberoptic scope and turn it on. Turn off the overhead room lights, if possible, or dim them to provide better contrast. Apply antifog solution onto the laryngoscope lens. Instruct the patient to protrude their tongue. Either the patient or the examiner may grasp the patient’s tongue with gauze as it protrudes (Figure 173-7). Hold the scope with both hands while stabilizing the nondominant hand against the patient’s face if the patient holds their own tongue. Hold the scope with the dominant index finger and thumb if the examiner is grasping the patient’s tongue (Figure 173-7). Stabilize the scope with the dominant fifth finger against the patient’s face. Instruct the patient to breathe slowly through their mouth in a “panting-like” manner. Insert the laryngoscope into the center of the mouth. Advance it straight backward and over the tongue. Stop advancing the scope when the circumvallate papillae are reached. Instruct the patient to phonate as described above. Advance the scope until the larynx is visualized (Figures 173-2 & 173-8). Tilt and
FIGURE 173-7. Positioning for a rigid telescopic examination of the larynx. Note that the telescope is stabilized on the left thumb and the left fifth finger is braced against the patient’s face.
FIGURE 173-8. Endoscopic view of the larynx through a rigid 90° telescope.
gently rotate the scope to visualize the entire larynx and hypopharynx during phonation and quiet breathing.
FLEXIBLE NASOPHARYNGOSCOPY OR NASOLARYNGOSCOPY A relatively new technology for laryngeal visualization is the “chipin-tip” laryngoscopes. Rather than fiberoptic cables, these flexible scopes have the video and lens apparatus at the tip of the scope and transmits the data to a processor. The processor converts the data into video images onto a screen. This scope produces a picture that is significantly brighter and less distorted (Figure 173-1C). It is an excellent tool for teaching. However, the cost for a complete digital unit is three to four times the cost of a traditional fiberoptic laryngoscope. Patient positioning is not crucial with this technique. Anesthetize the nasal passage so that the procedure is best tolerated. Visualize both nasal cavities with a nasal speculum to determine which nasal passageway will be easier to pass the scope through. Decongest the nasal mucosa with aerosolized oxymetazoline, 3% ephedrine, or cocaine. Instruct the patient to sniff in deeply after the spray is applied. Allow 3 to 5 minutes to pass for the vasoconstriction to occur. Apply a topical anesthetic spray to the nasal passageway. Spraying achieves excellent vasoconstriction and anesthesia as the agents diffuse through the entire nasal cavity and pharynx. Alternatively, place cocaine-soaked pledgets into the nasal cavity inferior and superior to the inferior turbinate for 10 minutes to achieve excellent anesthesia and vasoconstriction. Connect the light source to the fiberoptic scope and turn it on. Turn off the overhead room lights, if possible, to provide better contrast. Apply water-soluble lubricant onto the fiberoptic cord. Do not get the lubricant on the lens or it will blur visualization. Hold the eyepiece of the scope in the dominant hand (Figure 173-9). Use the dominant thumb to manipulate the tip controller. Grasp and hold the middle portion of the fiberoptic scope with the thumb and index finger of the nondominant hand. Brace the remaining fingers of the nondominant hand against the patient’s cheek (Figure 173-9). Insert the tip of the scope into the nose. Advance the scope with both hands and directed either along the floor of the nose or along the superomedial aspect of the inferior turbinate, depending
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FIGURE 173-9. Positioning for a nasal flexible fiberoptic examination of the larynx. Note that the left, nondominant, hand is stabilized against the patient’s face.
FIGURE 173-11. Nasopharyngoscopy using an external monitor for visualization of endoscopic images.
upon the nasal anatomy (Figure 173-10). Instruct the patient to breathe through their nose as the nasopharynx is encountered. This lowers the soft palate and opens the nasopharynx. Direct the tip of the endoscope downward and advance it past the oropharynx. Slide the tip of the scope behind the epiglottis, along the posterior pharyngeal wall, and into the hypopharynx and larynx. Avoid touching the epiglottis to prevent gagging and the vocal cords to prevent laryngospasm. Almost all patients can tolerate this procedure. Gagging is unusual. Apply a topical anesthetic agent to the oral cavity and oropharynx if the patient gags. Perform a leisurely and thorough examination of the airway. This is the only laryngoscopy technique in which normal speech can be observed.
much experience with this technique. An alternative, if available, is to connect the scope to a portable monitor (Figure 173-11). This makes the procedure less cumbersome and easier to perform. This type of setup is especially helpful in training situations (e.g., medical students, residents, and midlevel providers) as well as educating the patient and their family to the examination findings.
ALTERNATIVE TECHNIQUES The Emergency Physician must be looking through the rigid or flexible scope during the procedure. This in combination with holding, stabilizing, and advancing the scope makes fiberoptic laryngoscopy awkward if the Emergency Physician does not have
Sphenoid sinus
Auditory tube opening
Superior turbinate Middle turbinate Inferior turbinate
Routes for flexible scope
Hard palate
Choana
Soft palate
FIGURE 173-10. Anatomy of the lateral nasal wall and the two routes that the flexible scope can follow to gain access to the nasopharynx and subsequently the larynx.
AFTERCARE Inform the patient that the effects of the topical anesthetic persist an average of 30 to 45 minutes. Alert the patient that they may experience symptoms of aspiration, such as coughing or choking, when swallowing. Liquids are more likely to cause problems than solids. Instruct the patient not to ingest any solid or liquid substances until the topical anesthetic agent wears off. Mild bleeding from the scope abrading the mucosa is usually minimal and selflimited. The patient will need reassurance as rarely is any treatment required. Scopes require cleaning and disinfection between uses. Gently wipe any blood, lubricant, mucous, and other body fluids off the scope. Disinfect the scope per the manufacturers’ recommendations and hospital guidelines.
COMPLICATIONS Few complications arise from laryngoscopy. Epistaxis is possible with nasal endoscopy. It is uncommon when using vasoconstrictive agents and careful manipulation of the scope. Emesis is rare, even in the patient with an extremely sensitive gag reflex. Laryngospasm can be avoided as long as care is taken to avoid direct contact with the vocal cords. Although rare, the patient can have an adverse reaction to the local anesthetic agent or the decongestant. These should be evaluated and managed similar to any other allergic reaction. Aspiration during or after the procedure is extremely rare. Aspiration can be minimized by performing laryngoscopy on patients with an empty stomach, although this is often impractical in the Emergency Department. Other complications are minor and result from mechanical trauma. The tip of the scope can rub against and abrade the mucosa. This can result in mild irritation, rhinorrhea, and hemorrhage. Inappropriate technique or patient movement during the procedure can result in mucosal lacerations.
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SUMMARY
ANATOMY AND PATHOPHYSIOLOGY
Visualization of the larynx is a basic and often crucial component in the physical examination of the patient. A variety of techniques have been described, all of which are adequate in evaluating the larynx and hypopharynx. Risks and complications are rare. Maintain a very low threshold when deciding whether or not to perform laryngoscopy. Patient education and preparation are as, if not more, important than equipment and instrumentation in obtaining a thorough examination.
The airway is divided into three anatomic regions: the larynx, the trachea, and the bronchi. The laryngeal aditus is formed by the epiglottis anteriorly, the aryepiglottic folds laterally, and posteriorly by the corniculate cartilages and upper border of the arytenoid muscle. The larynx extends from the level of the aditus to the lower border of the cricoid cartilage, where it is continuous with the trachea.5 The infant larynx is located higher in the neck than the adult larynx. The cricoid cartilage descends in the neck through childhood. Due to the superior position of the infant larynx, the epiglottis is located with the tip often resting on the soft palate.6 The infant larynx is approximately one-third the size of the adult larynx. Laryngeal foreign bodies are most common in infants due to the small size of the inlet. Refer to Chapter 6 for a more complete discussion regarding the differences between the child and adult larynx. The trachea begins at the lower border of the cricoid cartilage, extending downward from about the level of the sixth cervical vertebra in adults or the fourth cervical vertebra in infants. The trachea extends inferiorly to the level of the carina. The inferior end of the trachea is located at the level of the fifth thoracic vertebra or the sternal angle. The trachea is 4 cm long in a full-term newborn infant and 11 to 13 cm long in an adult. The diameter of the trachea is 3.6 mm in a newborn and 12 to 23 mm in an adult.7 The trachea divides into two mainstem bronchi.7 The right mainstem bronchus is shorter, straighter, and larger in diameter than the left mainstem bronchus. This explains why right mainstem foreign bodies are more common than left mainstem foreign bodies. The mainstem bronchi divide into three lobar bronchi on the right and two on the left. The lobar bronchi divide into segmental bronchi. There are, usually, 10 segmental bronchi on the right, and 8 on the left.7 Airway foreign bodies commonly become lodged in one of three locations: the larynx, the trachea, or the bronchi. Laryngeal foreign bodies account for 4% to 5% of airway foreign bodies.8 Laryngeal foreign bodies have a mortality rate of 45% due to complete airway obstruction.9 Approximately one-third of survivors of transient airway obstruction suffer from hypoxic encephalopathy. Most choking victims are able to generate a forceful cough to expel an airway foreign body. Some patients are unable to relieve the obstruction themselves. The use of the Heimlich maneuver has further decreased mortality.10 It should be emphasized that the relief of an airway obstruction should only be attempted if signs of a complete airway obstruction are observed.11 Only perform oral cavity finger sweeps if a foreign body is seen within the oral cavity.11 Immediate intervention is not only unnecessary, but may be potentially dangerous if a patient is able to breathe, speak, or cough.12 Laryngeal foreign bodies can present with only mild or moderate respiratory distress. They may be located, or wedged, between the laryngeal ventricles, the true vocal folds, or the immediate subglottis (Figure 174-1A). Plain radiographs of the neck will detect radiopaque foreign bodies (Figures 174-1B & C). Flexible awake fiberoptic laryngoscopy allows visualization of the larynx and supraglottic structures. Tracheal foreign bodies account for 9% and bronchial foreign bodies account for 81% of airway foreign bodies.8 The classic diagnostic triad of a tracheobronchial foreign body consists of the sudden onset of paroxysmal coughing, wheezing, and diminished breath sounds on the affected side. However, these symptoms may only be present in 50% of cases. Approximately 33% of airway foreign bodies are neither observed nor suspected.13 Tracheal foreign bodies may present with audible biphasic or expiratory stridor. Audible expiratory wheezing is more likely associated with a
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Airway Foreign Body Removal David L. Walner
INTRODUCTION The presence of an airway foreign body is a common cause of morbidity and mortality in children, especially those younger than 3 years of age. Over 70% of foreign body aspirations occur in children.1 The mortality rate following foreign body aspiration is estimated at 1% to 2%. In the year 2000, ingestion or aspiration of a foreign body was the cause of 160 unintentional deaths and more than 17,000 Emergency Department visits in the United States.2 Other reports have estimated the death toll as high as 2000 per year in the United States.1 The most likely cause of death is complete airway obstruction, generally at the level of the larynx or trachea. Food objects have been associated with 41% and nonfood substances have been associated with 59% of reported deaths.2 Globular objects such as hot dogs, candies, chewing gum, nuts, and grapes are the most commonly aspirated food objects.3 Rubber balloons and toys are the most commonly aspirated nonfood objects.3 Parents and caregivers should be educated and aware of the types of food and objects that pose a choking risk for children. They should become familiar with the methods to reduce this risk. All parents and caregivers should learn the techniques to treat a choking child. Basic life support classes are often available free or at a minimal cost at hospitals, churches, and community centers. The management of airway foreign bodies requires specific expertise and training. Airway foreign bodies must be managed by an Otolaryngologist or other qualified Physician, depending on the institution, with experience in airway endoscopy and the knowledge to deal with the potential complications related to airway obstruction. Cases involving children require specialized expertise in pediatric airway endoscopy. Prior to the twentieth century, aspiration of a foreign body resulted in a 24% mortality rate. The morbidity and mortality associated with airway foreign body retrieval has greatly declined due to the development of safe endoscopic techniques, rod-lens telescopes, and optical forceps. The burden of proof lies in the Emergency Physician’s hands in order to diagnose an airway foreign body. Keep in mind that information gained from the history, physical examination, and radiologic studies may not clearly define the presence of a foreign body.4 Thirty-three percent of airway foreign body cases are neither observed nor suspected. The physical examination may be normal in up to 39% of patients. Radiographic studies may be normal in up to 20% of the patients. The only definitive test when considering the diagnosis of an airway foreign body is endoscopy to evaluate the entire laryngotracheobronchial tree.
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A
B
C
main bronchus obstruction. Tachypnea and cyanotic episodes may occur, generally when larger obstructing objects are present. Small foreign bodies may travel distally to a secondary bronchus and produce the more subtle symptoms of mild wheezing, cough, pneumonia, or fever. No abnormalities are found in up to 39% of patients.4 It is estimated that only 70% of patients with a foreign body aspiration seek treatment within the first week of the aspiration.14
FIGURE 174-1. Laryngeal foreign body. A. Coin lodged within the laryngeal ventricles resulting in a partial airway obstruction. B. Anteroposterior neck radiograph. C. Lateral neck radiograph.
The most common airway foreign bodies are food items and toys. Peanuts account for nearly 40% of tracheobronchial foreign bodies15 (Figure 174-2). Other common foreign bodies include plastic toys, pins, tacks, watermelon seeds, sunflower seeds, nails, screws, carrots, and popcorn. More than 80% of airway foreign bodies are radiolucent and can be difficult to diagnose. The most common radiologic findings are identified using both inspiratory
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A
B
FIGURE 174-2. Endoscopic view of a peanut in the right main-stem bronchus. A. Endoscopic view from just superior to the carina. Note that both mainstem bronchi are visible. B. Close-up view of the foreign body.
and expiratory chest radiographs. This can be in the form of a check valve with postobstructive hyperinflation and mediastinal shift to the contralateral side (Figure 174-3). It may also be seen in the form of a ball valve with atelectasis, collapse of the distal airways, and mediastinal shift to the ipsilateral side. Pneumonia can be present in 9% of cases, generally when the foreign body has been present for weeks or months. Chest radiographs can be normal in up to 11% to 20% of patients with tracheobronchial foreign bodies.4 Suspect an airway foreign body based upon the history, physical examination, and radiologic findings. However, the diagnosis is not always clear-cut. It is the responsibility of the Emergency Physician suspecting an airway foreign body to confer with the appropriate specialist and to strongly suggest endoscopy consisting of laryngoscopy and bronchoscopy. Endoscopy remains the gold standard to rule in or rule out an airway foreign body.
INDICATIONS The indications for airway endoscopy must take into account the patient’s history, physical examination, radiologic findings, and the suspected location of the foreign body. An accurate history is of the utmost importance in the diagnosis of foreign body aspiration as the remainder of the assessment, physical examination, and radiographic studies can be deceptively unremarkable. The characteristic history consists of an incipient choking or gagging episode. Caretakers often describe subsequent coughing spells when the event was witnessed. Aspiration must be assumed if the patient was eating peanuts, seeds, or beans during the episode. All witnessed aspirations with nuts or nondissolvable food matter require endoscopy and removal if the foreign material is identified.
CONTRAINDICATIONS The majority of patients presenting to the Emergency Department with airway foreign bodies are in stable condition. This allows time to adequately access the patient and formulate the best possible treatment plan. Infants and children with airway foreign bodies require an institution with the capability for comprehensive pediatric care. This includes a Physician who is experienced with
FIGURE 174-3. Chest radiograph of a patient with a left mainstem bronchus foreign body and a check valve-type of obstruction. Marks delineate the trachea and the mainstem bronchi.
CHAPTER 174: Airway Foreign Body Removal
airway endoscopy and foreign body retrieval in children, a facility with pediatric endoscopic equipment, pediatric anesthesia capabilities, and pediatric intensive care capabilities. This often will require transfer to a specialized pediatric center. Attempting removal of airway foreign bodies in a less-than-adequate environment can be catastrophic for the patient and is not advised. This same philosophy applies to adult airway endoscopy and to having qualified personal who are experienced in this area. Follow basic life support protocols, including the section on a choking victim, in the rare situation of an acutely obstructed airway. Any patient with a suspected laryngeal foreign body or impending airway obstruction requires emergent endoscopy and control of the airway in the Operating Room, if possible. If urgent endoscopy is not possible and a laryngeal foreign body is suspected, direct laryngoscopy in the Emergency Department and removal of a visualized foreign body with a McGill forceps can be attempted. A cricothyroidotomy or percutaneous transtracheal jet ventilation may be required as a lifesaving measure for a laryngeal foreign body if attempts at resuscitation and/or removal are unsuccessful. However, these two procedures are unlikely to be beneficial if the foreign body is located in the distal tracheal or bronchi. If urgent endoscopy is not available, and a lifesaving measure is required due to total airway obstruction of a distal tracheal or bronchial foreign body, orotracheal intubation with the tube positioned into one of the mainstem bronchi may be lifesaving. Based on the facility and the situation of total airway obstruction, ECMO could also be lifesaving.
EQUIPMENT Emergency Department Equipment • Intubation equipment • Percutaneous transtracheal jet ventilator • Cricothyroidotomy kit • Suction source, tubing, and catheter • Magill forceps • Laryngoscope with a variety of blades or a video laryngoscope • Topical anesthetic spray • Fiberoptic nasopharyngoscope
OPERATING ROOM EQUIPMENT The proper equipment must be selected based upon the patient’s age and size, as well as the suspected composition of the foreign body. Laryngoscopes are selected to allow visualization of the larynx and the passage of a bronchoscope. Rigid, ventilating bronchoscopes with fiberoptic telescopes provide optimal visualization. This allows direct access to the airway, excellent visualization, continuous administration of anesthetic agent and oxygen, and a conduit for the introduction of instruments (forceps) to retrieve the foreign object. Multiple sizes of laryngoscopes and bronchoscopes are essential to have available in the operating room. Numerous extraction instruments (of different sizes and shapes) must be available and include smooth, toothed, cupped, angled, open mouth, and optical forceps. The optical forceps allow a magnified and direct view through the forceps improving visualization and ease of foreign body removal.
PATIENT PREPARATION Timing of endoscopy and airway foreign body retrieval must be based upon each individual patient. Do not waste time if impending airway obstruction exists. Immediately notify and mobilize an
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Anesthesiologist, Otolaryngologist, and the Operating Room, as this is an emergent situation. It is appropriate to wait for NPO status to be present and the stomach empty prior to proceeding to the Operating Room if the diagnosis of an airway foreign body is highly suspected and the patient is stable. This is considered a timely approach and may take up to 6 hours for children or 8 hours for adults. Waiting this time in the stable patient decreases the risk of aspiration and further compromising the situation. It is also appropriate to wait, in a stable patient, in order to assemble the appropriate and best nursing and anesthesia team to care for the patient. Using personnel who are unfamiliar with endoscopy can create a compromised and stressful situation.
TECHNIQUES EMERGENCY DEPARTMENT TECHNIQUES The foreign body airway obstruction protocol based upon the Pediatric Basic Life Support textbook treats conscious infants (younger than 1 year of age) with four back blows while the infant is in a prone position on the rescuer’s forearm, face down, and the head lower than the trunk. This is combined with four rapid chest thrusts (as in infant CPR), if the obstruction persists, while the infant is supine with the head lower than the body.11 Treat unconscious infants by opening the airway and attempting rescue breathing based on basic life support protocols.11 Treat children and adults with the standard Heimlich maneuver, using gentle thrusts in smaller children to decrease the likelihood of injury to the abdominal organs. Finger sweeps to remove a foreign body in the oral cavity should only be performed if the foreign body is directly visualized. Blind finger sweeps are not recommended as they can further impact the foreign body and obstruct the airway. It is always best not to manipulate the airway or attempt intubation in a stable patient with an airway foreign body and who is moving air and breathing. The airway is best controlled in the Operating Room at the time of the actual foreign body removal. Once the airway is manipulated a foreign body can become dislodged, turning a partial airway obstruction into a complete airway obstruction. If this occurs in the Operating Room, the bronchoscopy equipment is available for urgent use by the endoscopist if needed. Attempt orotracheal intubation in the Emergency Department if the airway obstruction progresses rapidly and the patient cannot ventilate. Intubation can be used to force the foreign body into one mainstem bronchus and allow ventilation of the other lung. One-lung ventilation will keep the patient alive until the foreign body can be removed in the Operating Room. Position the laryngoscope to visualize the larynx. If a foreign body is visualized, grasp the foreign body with a McGill forceps and remove it. If no foreign body is visualized, intubate the patient. Insert and advance the endotracheal tube as far as it will advance if the foreign body is not visualized or unable to be grasped. If the endotracheal tube will not pass, try a smaller size tube. Withdraw and position the endotracheal tube with the tip above the carina to optimize ventilation. As an alternative, properly insert and position the endotracheal tube above the carina then advance a bougie through the endotracheal tube in an attempt to move the foreign body distally. Always be prepared to perform a cricothyroidotomy or transtracheal jet ventilation. Transtracheal jet ventilation allows for short-term oxygenation, is temporary, and may allow time for safe transport to the Operating Room so that endoscopy and foreign body retrieval can be performed in a more controlled environment with appropriate equipment at hand. Refer to Chapters 11, 25, and 24 regarding the details of orotracheal intubation, cricothyroidotomy, and transtracheal jet ventilation, respectively.
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Direct laryngoscopy and bronchoscopy in a child or adult with an airway foreign body is a dangerous situation. The procedure may result in a partial airway obstruction becoming a complete airway obstruction. Always have a cricothyroidotomy tray immediately available. All equipment must be selected, assembled, and ready for use. It is possible to remove foreign bodies located within the hypopharynx in the Emergency Department. Typical foreign bodies that may be removed include pieces of food and fishbones. The patient must be stable and in no risk of airway compromise. Obtain anteroposterior and lateral soft tissue radiographs of the neck to localize, if possible, the foreign body. The use of CT scans to attempt to identify potential fish or chicken bones that may be lodged in the pharynx, hypopharynx, or esophagus is an option in the stable patient. Perform indirect laryngoscopy to identify the foreign body and its location. Refer to Chapter 173 regarding the complete details of laryngoscopy. Obtain intravenous access. Place the patient in full monitoring (i.e., pulse oximeter, cardiac monitor, noninvasive blood pressure cuff). Apply a topical anesthetic spray to the oropharynx and the base of the tongue. Place the patient supine. Administer a small dose of an intravenous sedative if required. Slowly and gently insert a #3 Miller laryngoscope blade. An alternative to a traditional laryngoscope, if available, is a video laryngoscope. The video laryngoscope may provide a better field of view with less manipulation. Do not immediately insert the laryngoscope blade all the way. Stop frequently to lift the laryngoscope and look for the foreign body. This slow insertion and frequent looks will prevent the laryngoscope blade from pushing the foreign body further into the airway. Elevate the patient’s tongue and jaw. Grasp the foreign body with a McGill forceps. Withdraw the McGill forceps followed by the laryngoscope.
ALTERNATIVE TECHNIQUE The use of a flexible fiberoptic bronchoscope to retrieve bronchial foreign bodies may be acceptable for Physicians who are well trained with this technique. The mainstay of tracheobronchial foreign body retrieval remains to be rigid bronchoscopy.
AFTERCARE After the retrieval of an airway foreign body, most patients should be breathing spontaneously. An endotracheal tube may rarely, in the presence of significant laryngeal or tracheobronchial edema, need to remain in place temporarily. This would require admission to an intensive care unit. Humidified oxygen is helpful to keep the airway moist and prevent mucous crusts from forming. A postprocedural radiograph will help to determine any subcutaneous air, air in the soft tissues, a pneumothorax, or any changes to the lung fields following the extraction. All patients who have undergone foreign body removal require at least a few hours of airway observation in a monitored setting. Racemic epinephrine treatments and intravenous Decadron can be administered as needed. Discharge from the hospital is acceptable when the patient is breathing comfortably and no longer in danger of airway compromise. Some patients may be discharged home the same day, while others may require multiple days of airway support and observation. In cases where a bronchial foreign body has been present for a prolonged period of time, granulation tissue and severe inflammation can form around the foreign body making removal difficult or impossible. It may be necessary to treat the patient with intravenous steroids and antibiotics for 48 hours, with or without intubation, followed by a repeat bronchoscopy and a repeat attempt to remove the foreign body.
OPERATING ROOM TECHNIQUES The procedure begins with the induction of general anesthesia. It cannot be overemphasized that anesthesia should only be administered by an Anesthesiologist who is competent and comfortable with the situation. Pediatric patients require an Anesthesiologist with pediatric airway experience if the patient is stable. Full monitoring and mask induction allow the patient to maintain spontaneous respiration. Muscle relaxants are avoided as they can induce complete airway obstruction. The Otolaryngologist begins the procedure. Place the patient supine with a shoulder roll to position the airway. Insert the laryngoscope into the larynx. Expose the larynx by elevating the laryngoscope. Topical anesthetic is applied to the larynx to avoid laryngospasm. The bronchoscope with telescope is then passed under direct vision through the mouth and into the laryngeal introitus. Ventilation can continue via a port on the scope. The foreign body is visualized. Forceps are inserted through the scope and used to grasp the foreign body. Small objects can be removed directly through the scope, whereas larger objects require simultaneously removing the bronchoscope along with the forceps and foreign body. The bronchoscope is passed again, after removal of the foreign body, to identify any mucosal injury or second foreign body that may occur in as many as 5% of patients.4 If purulent secretions are noted, a culture may be obtained and antibiotics administered appropriately. A specific type of foreign body, such as a tack or sharp object, may become lodged in the larynx or upper trachea. Extraction with the forceps using standard endoscopic techniques may not be possible. Patients may require a tracheotomy and an open approach (laryngotomy) to remove the foreign body.
COMPLICATIONS Complications from the foreign bodies themselves include hypoxia leading to cerebral anoxia if not identified. Intraoperative complications can occur in the hands of an inexperienced endoscopist or even an experienced endoscopist who loses control of a foreign body in the airway and is faced with obstruction or respiratory arrest. Cardiac arrhythmias can occur from hypoxia or direct pressure on the left main-stem bronchus. Postoperative problems can include laryngeal or tracheobronchial edema from the foreign body or the instrumentation of the airway. Mucosal irritation can instigate a tracheitis or bronchitis. Pneumonia can develop. Pneumomediastinum has been reported in as many as 13% of aspirations and a pneumothorax slightly less frequently.16 A foreign body pulled up from a main stem bronchus can become dislodged in the larynx or trachea and cause a complete airway obstruction. A foreign body in the hypopharynx can be pushed distally and result in a total airway obstruction. The foreign body needs to be quickly removed, pushed back down into one of the mainstem bronchi to allow ventilation of at least one lung, or a surgical airway performed. Failure to react appropriately in this situation can result in asphyxiation and death.
SUMMARY Airway foreign bodies pose a diagnostic and therapeutic challenge. The initial encounter in the Physician’s office, clinic, or the Emergency Department must uncover any historical fact, physical abnormality, or radiographic abnormality that may lead to a definitive or presumed diagnosis of an airway foreign body. Endoscopy
CHAPTER 175: Peritonsillar Abscess Incision and Drainage
must be performed by a skilled team to allow safe and efficient removal of the foreign body. Hypopharyngeal foreign bodies may be safely removed in the Emergency Department by a trained Emergency Physician.
175
Peritonsillar Abscess Incision and Drainage Eric F. Reichman, Kellie D. Hughes, and Jehangir Meer
INTRODUCTION A peritonsillar abscess is the most common deep infection of the head and neck encountered in young adults in the Emergency Department.1 The incidence is approximately 45,000 cases per year.2 This infection can occur in all age groups, although it is a relatively rare before the age of 5 years. The highest incidence occurs in adults 20 to 40 years of age. There remains a fair amount of controversy in the literature regarding the optimal antibiotic choice and the mechanism of drainage. The objective for the Emergency Physician remains to make an accurate diagnosis, to institute appropriate care, and to arrange timely follow-up.
ANATOMY AND PATHOPHYSIOLOGY Knowledge of oropharynx anatomy is imperative. The anatomy of the oral cavity is relatively simple (Figure 175-1). The peritonsillar abscess can be found posterolateral to the palatine tonsil and posterior to the palatoglossal fold (or arch). Note the close proximity of the internal carotid artery and the facial artery to the
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peritonsillar abscess (Figure 175-2). Use extreme care to not penetrate too deeply and lacerate these arteries. Most patients will have had symptoms for approximately 4 days by the time abscess formation has occurred. The most common symptoms include fever, sore throat, dysphagia, muffled voice (the “hot potato” voice), and trismus. Physical examination will reveal a nonexudative pharyngitis in the majority of cases, soft palate edema, a bulging prominent tonsil, and uveal deviation away from the abscessed tonsil (Figure 175-3). The differential diagnosis includes intratonsillar abscess, peritonsillar cellulitis, infectious mononucleosis, leukemias, odontogenic infections, and aneurysms of the internal carotid artery. Intraoral ultrasound (US) for a peritonsillar abscess has been performed since the 1990s. It was first described in the Otolaryngology literature and subsequently in the Emergency Medicine literature. The first case series of patients whose peritonsillar abscesses were drained under US guidance was described by Blaivas and colleagues.3 Since that time, US guidance has been shown to have a high degree of sensitivity (85% to 92%) and specificity (80% to 100%).4,5 US offers the advantage of confirming the presence of an abscess prior to aspiration attempts as well allowing visualization of important neighboring structures (e.g., the internal carotid artery). Some patients with a peritonsillar abscess may be misdiagnosed with cellulitis and not undergo drainage. The use of US can prevent this. A significant proportion of patients (10% to 24%) have false-negative results on blind aspiration because the peritonsillar abscess can be multilocular and its location can vary.4,6,7 US will identify the location of the abscess to limit the number of false-negative aspirations. The peritonsillar abscess has been attributed to progression and direct extension of an acute exudative pharyngitis. More recent work has described a group of salivary glands, Weber’s glands, located in the supratonsillar space as the actual site of bacterial invasion and subsequent abscess formation.8,9 The glands clear the tonsillar area of debris and assist with the digestion of food particles trapped in
Posterior wall of oral portion of pharynx Palatopharyngeal fold Palatoglossal fold Vallate papillae
Hard palate Soft palate Uvula Palatine tonsil
Sulcus terminalis Tongue FIGURE 175-1. Anatomy of the oropharynx as seen through the open mouth.
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SECTION 13: Otolaryngologic Procedures Superior constrictor muscle Palatopharyngeus muscle Peritonsillar abscess External palatine vein Carotid sheath
Facial artery
Internal jugular vein Tonsillar artery
Internal carotid artery Ramus of mandible
Palatine tonsil
Palatoglossus
Vestibule of mouth
Vallecula Glossoepiglottic fold
Buccinator muscle
Lower lip FIGURE 175-2. Horizontal section through the mouth and oropharynx. Note the close proximity of the peritonsillar abscess to the internal carotid artery and the facial artery.
the tonsillar crypts. If the Weber’s glands become inflamed, a local cellulitis can develop.9 The bacterial inoculum results in tissue necrosis and pus formation typically located between the tonsillar capsule and the lateral pharyngeal wall and/or the supratonsillar space. Progression of pus formation and cellulitis within the supratonsillar space results in a gradual involvement of the surrounding
Hard palate Soft palate Deviated uvula
Tonsil Peritonsillar abscess
musculature, particularly the internal pterygoids, leading to spasm and trismus. Most peritonsillar abscesses are caused by a mixed profile of aerobic and anaerobic organisms.10 The most common aerobic isolate found on culture remains group A beta-hemolytic streptococci.1,9–11 The most common anaerobic species are peptostreptococcus, prevotella, and Fusobacterium.1 Other isolates include Staphylococcus aureus, Bacteroides fragilis, and Bacteroides melaninogenicus. There is an increasing prevalence of beta-lactamase producing organisms.11 Treatment options for a peritonsillar abscess have undergone a significant amount of debate in the literature. Treatment requires appropriate antibiotic selection and removal of purulent fluid. Techniques of fluid removal range from simple or single aspiration of the abscess, repeated aspirations, and incision and drainage. Patients treated with aspiration alone have success rates ranging from 85% to 100%.2,12,13 The cure rates for simple aspiration versus incision and drainage are similar.14–18 The overall recurrence rate is less in patients undergoing incision and drainage.2,12,13
INDICATIONS
FIGURE 175-3. A peritonsillar abscess. The abscess displaces the tonsil forward and medially. The uvula is deviated toward the contralateral side.
All peritonsillar abscesses require either aspiration or incision and drainage. The gold standard to diagnose a peritonsillar abscess remains the collection of pus through needle aspiration or the identification of a peritonsillar fluid collection using US. The decision regarding the drainage technique is left to the Emergency Physician’s preference and, when possible, in consultation with an Otolaryngologist.
CHAPTER 175: Peritonsillar Abscess Incision and Drainage
US may be used to confirm the presence of a peritonsillar abscess, to guide needle aspiration of a confirmed peritonsillar abscess, and/ or rescue a failed blind needle aspiration. The use of US can confirm the presence of a cellulitis with no underlying abscess. It will also confirm that the “mass” is not an aberrant internal carotid artery.19
CONTRAINDICATIONS There are no absolute contraindications to draining a peritonsillar abscess. Patients with severe trismus limiting visibility and access may require intravenous analgesics and muscle relaxants, procedural sedation, or intraoperative drainage. Consult an Otolaryngologist for all patients who are coagulopathic, taking oral anticoagulants, or with a known bleeding disorder. These patients are at risk for significant bleeding and associated complications. Admit children to the hospital for intravenous antibiotics, incision and drainage under general anesthesia, and possible tonsillectomy. The procedure should be avoided in patients who are uncooperative, unable to follow instructions, unable to sit upright, and those that are very young to prevent iatrogenic complications.
EQUIPMENT General Supplies • #11 scalpel blade on a handle • Curved hemostat • Frazier suction catheter • Suction source and tubing • Tongue depressors • Topical anesthetic spray (Cetacaine, lidocaine, tetracaine, or benzocaine) • Syringe, 3 or 5 mL • 25 or 27 gauge needle, 2 inches long • Local anesthetic solution with epinephrine • 10 mL syringe • 18 gauge needle • Culturettes or culture bottles • Headlamp or adjustable overhead light source • Gloves • Face mask with an eye shield
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• Gown • Oral rinse solution, hydrogen peroxide or Peridex Us Guidance • US machine • High frequency, endocavitary US probe • Sterile US gel • US probe cover
PATIENT PREPARATION Explain the procedure, its risks, and benefits to the patient and/ or their representative. Obtain a signed informed consent for the procedure. Ensure that the patient has a thorough understanding of the postprocedural care instructions and follow-up requirements. Position the patient sitting in an upright multipositional procedure chair. Alternatively, place the patient sitting upright on a gurney with the back elevated. Prepare the wall suction unit to ensure it is working. Apply suction tubing and a suction catheter to the suction source. The Emergency Physician should wear gloves, a gown, and a face mask with eye protection. This protective wear will prevent against becoming exposed or contaminated with oral secretions or abscess contents during the procedure if the patient coughs. The use of good lighting cannot be overemphasized. Apply a headlamp if one is available. An alternative is an overhead adjustable light source. Position the light so that it is aimed in the patient’s mouth. The overhead light often hits the examiner in the head, casts shadows, is too bright for the patient’s eyes, and is also difficult to properly position because both of the Emergency Physician’s hands must be used for the procedure. An additional alternative is to use the bottom half of a vaginal speculum with a fiberoptic light source.25 This requires an assistant to position and hold the speculum against the tongue and apply downward pressure. Incision and drainage must be preceded by adequate anesthesia to the abscess site. Determine the most fluctuant region of the abscess. Anesthetize this area. Spray topical anesthetic over the abscess (Figure 175-4A). Dry the mucosa overlying the peritonsillar abscess with a gauze square. Arm a 3 mL syringe with a 25 or 27 gauge needle. Inject 1 mL of local anesthetic solution containing epinephrine through the area of topical anesthesia and just under the mucosal surface (Figure 175-4B). Allow 3 to 5 minutes for the anesthetic to work.
FIGURE 175-4. Anesthesia techniques. A. Topical spray anesthesia. B. Infiltrative anesthesia.
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A
B
FIGURE 175-5. Safety techniques to prevent injury to the internal carotid artery. A. The needle cover is cut and placed over the needle as a guard. B. Tape applied to an 18 gauge needle. C. Tape applied to a #11 scalpel blade.
TECHNIQUES ASPIRATION Identify the area of maximal fluctuance at the upper pole of the abscess. Anesthetize the area as described previously. Prepare the equipment. Apply an 18 gauge needle onto a 10 mL syringe. A smaller needle may not allow thick pus to be aspirated. Break the seal of the syringe. Trim the needle cap and place it over the needle to act as a depth gauge (Figure 175-5A). The needle should project only 1 cm from the distal end of the needle cap. Alternatively,
FIGURE 175-6. Needle aspiration of a peritonsillar abscess. A. Recommended sites for needle aspiration. B. Aspiration in the first area.
C
apply a piece of tape onto the needle to mark a point 1 cm from the tip of the needle (Figure 175-5B). The guard (cap or tape) serves as a marker for the maximum allowable depth to insert the needle during the procedure. Limiting of the depth of insertion of the needle will prevent injury to the carotid artery that is located approximately 1.5 to 2 cm posterior and lateral to the tonsil. Depress the tongue with a tongue depressor held in the nondominant hand (Figure 175-6A). Insert the prepared needle attached to the syringe into the upper pole of the abscess, into the point of maximal fluctuance (Figures 175-6A & B).14,17,20,21 Hold and advance the needle parallel to the floor and directly posterior.
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FIGURE 175-7. Incision and drainage of a peritonsillar abscess. A. The incision site is also the same site for the first aspiration. B. Incision with a #11 scalpel blade. Note the tape marking the maximum insertion depth of the scalpel blade. Suction any bloody or purulent fluid that escapes from the incision. C. Hemostat gently inserted to break any loculations.
Do not direct the needle laterally where it can injure the carotid artery. Aspirate while advancing the needle. Approximately 85% to 90% of abscesses occur in the upper pole of the tonsil.14,17 If purulent fluid is obtained, continue to aspirate and remove as much purulent material as possible. Obtain a culture and sensitivity of the aspirated material. Allow the patient to rinse and spit several times with Peridex solution or half-strength hydrogen peroxide solution. If the initial aspirate is negative, reattempt the procedure by inserting the needle into the middle pole and then the inferior pole of the abscessed tonsil until purulent material is obtained (Figure 175-6A). A completely negative aspiration, while more consistent with a tonsillar cellulitis, does not rule out the existence of an abscess. Gentle palpation will reveal fluctuance when an abscess if present.
INCISION AND DRAINAGE It is recommended to always perform a needle aspiration prior to the incision and drainage technique. Aspiration will localize the collection of pus and allow a more accurate incision and drainage. A negative aspiration at all three sites (Figure 175-6A) is a contraindication for an incision and drainage procedure. It may be too early and an abscess has not yet formed. A negative aspiration at all three sites suggests that the patient has a tonsillar cellulitis requiring oral antibiotics, gargles with hydrogen peroxide, and follow-up in 24 hours for reevaluation. Identify the area of maximal fluctuance at the upper pole of the abscess. Anesthetize the area as described previously. Prepare the equipment. Place a piece of tape on the #11 scalpel blade so that only 0.75 to 1 cm is exposed (Figure 175-5C). Place the Frazier suction catheter near the incision site. Insert the scalpel blade to make a horizontal stab wound to a maximum depth of 1 cm in the same area noted for the aspiration technique (Figures 175-7A & B). The Frazier suction catheter will remove any blood and purulent material to prevent the patient from aspirating. The depth of the stab should be no more than 1 cm. Extend the length of the incision to a maximum of 1.0 to 1.5 cm. Insert a curved hemostat into the wound (Figure 175-7C). Gently spread apart the jaws of the hemostat to break up any loculations in the abscess. Continue to simultaneously suction the area during the procedure. Packing of the abscess cavity is not required. Obtain a culture and sensitivity of the purulent material. Allow the patient
to rinse and spit several times with Peridex solution or half-strength hydrogen peroxide solution. Leave the suction in the patient’s hand so they can use it as needed.
US GUIDANCE Anesthetize the area as described previously. Prepare the equipment. Place sterile US gel on the transducer surface of the US probe. Apply the US probe cover. Take care to avoid trapping air bubbles between the cover and the US probe, as they can seriously degrade the image. Apply sterile US gel over the covered US probe transducer surface. Gently insert the US probe into the patient’s oral cavity. Direct the US probe to the peritonsillar area and until it rests lightly against the posterior pharynx (Figure 175-8). Maintain the US probe in a transverse orientation to maximize visualization of the posterior pharynx. Note the location of the palatine tonsil, a small oval structure with low-level echoes, and the internal carotid artery (Figure 175-9). A peritonsillar abscess can have variable appearances on US. They usually are heterogeneous, cystic, and
FIGURE 175-8. Placement of the endocavitary US probe inside the oral cavity and directed against the peritonsillar area.
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FIGURE 175-9. Transverse color Doppler scan of the normal posterior pharynx. The tonsil (T) is visible on the top of the image. The internal carotid artery is noted by its red color Doppler signal.
FIGURE 175-10. Intraoral ultrasound image. The needle (arrows) is inserted into the peritonsillar abscess (A). The tonsil ( T ) is visible on the top of the image. The internal carotid artery is not visualized in this image.
adjacent to the tonsil (Figure 175-10). The carotid artery usually lies 5 to 20 mm posterolateral to the tonsil. Note the depth and location of the abscess. After the presence of a peritonsillar abscess is confirmed and its location mapped, proceed using the previously described techniques for aspiration or incision and drainage. Alternatively, perform a needle aspiration under real-time US guidance. Use the long axis approach to direct the needle into the peritonsillar abscess (Figure 175-10).
Admission is generally required for patients who appear toxic, pediatric patients, dehydrated patients, immunocompromised patients, recurrent abscesses, and for patients who are unable to tolerate oral fluids. These patients require observation for 23 hours and intravenous antibiotics.
ASSESSMENT Incision and drainage will result in significant relief of the patient’s pain and trismus. Allow the patient to rinse and spit with either Peridex solution or half-strength peroxide solution. Observe the patient for any evidence of continued bleeding or upper airway symptomatology. Assess the patient’s ability to tolerate oral fluids prior to discharge.
AFTERCARE Discharge the patient with oral antibiotics and analgesics. Penicillin used to be the antibiotic of choice. The emergence of betalactamase-producing organisms has required a change in antibiotic choice.10 Use clindamycin, or a second or third generation cephalosporin, to treat peritonsillar abscesses due to their polymicrobial coverage.9,10 If penicillin is used, many Otolaryngologists will add either clindamycin or metronidazole due to the increasing incidence of penicillin-resistant organisms.2,22 Nonsteroidal antiinflammatory drugs will adequately control any pain and fever. Consider the administration of 3 mg/kg, to a maximum of 250 mg, of methylprednisolone to decrease pain and inflammation.23 Recommend to the patient to follow a soft diet and drink plenty of fluids during the first 48 hours after the intervention. Instruct the patient to gargle with half-strength hydrogen peroxide or Peridex after each meal, at a minimum, and several other times per day. Arrange follow-up within 48 hours, or sooner if they do not improve. Instruct the patient to return to the Emergency Department immediately if they develop bleeding, shortness of breath, difficulty swallowing, drooling, or have any concerns.
COMPLICATIONS There are few complications associated with the management of a peritonsillar abscess. Potential complications include aspiration pneumonitis, airway obstruction, hemorrhage, or extension of infection into deep tissue of the neck. Aspiration pneumonitis or lung abscess can occur secondary to abscess rupture.9 Protect against aspiration of purulent material and subsequent pulmonic infection by having the patient sit upright during the procedure and using suction as the abscess is opened. Making an incision that is too large or too deep can injure the carotid artery (or a carotid artery aneurysm) which could result in prolonged bleeding or hemorrhage. Always limit the depth of the needle or scalpel insertion. The use of US to locate and assist in the drainage of a peritonsillar abscess is associated with several pitfalls. Failure to recognize the internal carotid artery can be catastrophic for the patient. Always note the relationship of the tonsil and the peritonsillar abscess to the internal carotid artery.24 The internal carotid artery lies posterolateral to the tonsil. The use of color Doppler can assist in the identification of the carotid artery and differentiate it from the peritonsillar abscess. US may fail to identify a peritonsillar abscess. Although fluid within a peritonsillar abscess is usually hypoechoic, it can appear isoechoic or hyperechoic.
SUMMARY A peritonsillar abscess is commonly encountered in the Emergency Department. Diagnosis and treatment result in rapid symptom resolution in the majority of patients. Admission may be required in a few instances for observation and intravenous antibiotics. Appropriate antibiotics after the procedure can prevent a recurrence of the peritonsillar abscess.
SECTION
Dental Procedures
176
Dental Anesthesia and Analgesia Eric F. Reichman
INTRODUCTION Dental anesthesia techniques are used by Emergency Physicians for a variety of intraoral and extraoral conditions. This includes dental caries, jaw fractures, dry sockets, intraoral hemorrhage, laceration repair, and tooth fractures. These techniques are simple to learn, easy to perform, and provide temporary pain relief for the patient. The Emergency Physician can provide pain-free intraoral manipulations, extraoral manipulations, facial manipulations, and simple pain control until the patient receives definitive evaluation and treatment by a Dentist or Oral Surgeon. The fundamental principles of dental anesthesia and anatomy will be discussed so that the Emergency Physician will feel knowledgeable and comfortable performing dental anesthetic techniques.
ANATOMY AND PATHOPHYSIOLOGY An understanding of the anatomy of the fifth cranial nerve is essential to performing dental nerve blocks1 (Figure 176-1). The fifth cranial nerve is also referred to as CN V or the trigeminal nerve. It is the largest cranial nerve. It is a mixed cranial nerve containing
Nasociliary nerve Lacrimal nerve Supraorbital nerve
14
primarily sensory fibers to the skin of the face and scalp, the nasal cavity, and the oral cavity. The motor fibers innervate the muscles of mastication. The trigeminal nerve originates in the brainstem as a small motor root and a large sensory root. These roots fuse as they leave the brainstem. The trigeminal nerve travels forward into the middle cranial fossa where it expands into a large and crescent-shaped trigeminal ganglion. The trigeminal ganglion divides to give rise to the three divisions of the trigeminal nerve: the ophthalmic nerve (V1), the maxillary nerve (V2), and the mandibular nerve (V3) (Figure 176-1). Each of these nerves leaves the middle cranial fossa through its own foramen.
OPHTHALMIC NERVE The ophthalmic nerve is the smallest branch of the trigeminal nerve. It travels forward in the lateral wall of the cavernous sinus and enters the orbit via the superior orbital fissure. It provides sensory innervation to the forehead, scalp, upper eyelid, cornea, nasal cavity, sinuses, and the orbit. This nerve is not discussed further because it does not innervate any oral or dental structures.
MAXILLARY NERVE The maxillary nerve is purely sensory. It travels forward in the lateral wall of the cavernous sinus and exits the cranial vault via the foramen rotundum into the pterygopalatine fossa. It then enters the
Ophthalmic nerve (V1) Maxillary nerve (V2) Trigeminal ganglion Trigeminal nerve
Infraorbital nerve Superior alveolar nerves: Posterior Middle Anterior
Auriculotemporal nerve Mandibular nerve (V3)
Lingual nerve
Mylohyoid nerve Inferior alveolar nerve
FIGURE 176-1. The anatomy of the trigeminal nerve. 1131
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orbit through the inferior orbital fissure to continue on as the infraorbital nerve and emerge on the face. The infraorbital nerve terminates as a sensory nerve to the lower eyelid, upper cheek, nose, and upper lip. The infraorbital nerve gives off the anterior superior alveolar nerves prior to its termination. These nerves supply the maxillary sinus, the maxillary incisors, the maxillary canine teeth, and the maxillary premolar teeth. The anterior superior alveolar nerve occasionally crosses the midline to supply the contralateral maxillary incisors. The maxillary nerve forms numerous branches in the pterygopalatine fossa. The zygomaticofacial and zygomaticotemporal nerves are cutaneous to the face and temple. The nasal and nasopalatine nerves supply the nasal cavity and floor of the nasal cavity. The nasopalatine nerve exits the nasal canal through the midline incisive foramen, just posterior to the central incisors. It provides sensory innervation to the anterior hard palate and associated soft tissues. The greater palatine nerve exits the greater palatine foramen to provide sensory innervation to the posterior two-thirds of the hard palate. The lesser palatine nerve exits the lesser palatine foramen and provides sensory innervation to the soft palate. The greater and lesser palatine nerves exit 1 cm medial to the junction of the second and third molar on the hard palate. The middle superior alveolar nerve provides sensory innervation to the premolars, and occasionally the canine and the first molar teeth. The posterior superior alveolar nerve provides sensory innervation to the molars and, occasionally, the premolars.
MANDIBULAR NERVE The mandibular nerve is the largest division of the trigeminal nerve. It is the only division of the trigeminal nerve to contain motor fibers. The mandibular nerve exits the middle cranial fossa via the foramen ovale. It provides branches to the meninges and the small muscles of the palate and the medial pterygoid muscle. It divides into a small anterior division and a large posterior division. The anterior division of the mandibular nerve is primarily motor. It innervates the muscles of mastication (i.e., masseter, temporalis, and lateral pterygoid). The sensory portion of the anterior division is the buccal nerve. This nerve travels between the two heads of the lateral pterygoid muscle, under the masseter muscle, and emerges from the anterior border of the masseter muscle. It travels forward to innervate a small and variable portion of the skin of the cheek. It primarily innervates the mucous membranes of the cheek. The posterior division of the mandibular nerve is purely sensory. It divides into the auriculotemporal, inferior alveolar, and lingual
nerves. The auriculotemporal nerve supplies sensory innervation to the skin of the auricle, external auditory canal, scalp, and temporomandibular joint. It conveys postganglionic parasympathetic fibers to the parotid gland. The lingual nerve descends into the mouth and travels along the lateral surface of the tongue. It supplies sensory innervation to the anterior two-thirds of the tongue and the floor of the mouth. The lingual nerve receives, near its origin, and conveys the chorda tympani from the facial nerve. The chorda tympani provides taste sensation to the anterior two-thirds of the tongue and preganglionic fibers to the submandibular ganglion for the submandibular and sublingual glands. The inferior alveolar nerve descends immediately posterior and adjacent to the lingual nerve. It enters the upper one-third of the ramus of the mandible, posterior to the lingula, to enter the mandibular canal. It provides sensory innervation to the mandible, the mandibular teeth, and the adjacent mucous membranes. The inferior alveolar nerve gives origin to the mental nerve. The mental nerve exits the mental foramen located on the outer surface of the mandible between the first and second premolars. It supplies sensory innervation to the lower lip, the skin of the chin, and the mucous membrane of the chin.
INDICATIONS Dental nerve blocks can be performed to provide temporary relief of pain. They are often used to provide relief from alveolar ridge fractures, dental caries, dry sockets, mandible fractures, and tooth fractures. Nerve blocks can be performed prior to painful intraoral procedures such as incision and drainage of dental abscesses and laceration repair to the cheek, lips, oral mucosa, and tongue. Nerve blocks do not distort the local anatomy, when compared to infiltration of the surrounding soft tissue with local anesthetic solution, and allow better approximation of the wound edges during suturing. Nerve blocks are an excellent alternative if narcotic analgesics are contraindicated or to be avoided. Local anesthetic solutions containing epinephrine can be utilized to provide longer pain relief and vasoconstriction along the nerve distribution (Table 176-1).
CONTRAINDICATIONS The two absolute contraindications to dental anesthesia include a known hypersensitivity to the anesthetic agent and gross distortion of the anatomic landmarks required to perform the nerve
TABLE 176-1 Local Anesthetic Solutions Commonly used in Dental Anesthesia Procedures
Anesthetic solution 1% procaine 1% procaine with epinephrine 2% lidocaine 2% lidocaine with epinephrine 3% mepivacaine 2% mepivacaine with epinephrine 4% prilocaine 4% prilocaine with epinephrine 4% articaine with epinephrine 0.5% bupivacaine 0.5% bupivacaine with epinephrine
Proprietary name Novocaine™ Xylocaine™ Carbocaine™ Citanest™ Septocaine™ Marcaine™
Time of onset (minutes) 6–10 6–10 2–5 2–5 5 5 3–5 3–5 1–3 5 5
Pulpal duration of action (minutes) 10 15 10 60 5–10 45–60 10–60 60–90 45–75 60–90 90–120
* Do not exceed this quantity if the maximum weight-based dose is larger than this number.
Soft tissue duration of action (minutes) 15–90 15–120 30–45 180–300 90–120 120–140 60–240 180–480 180–300 240–280 240–720
Maximum dose (mg)* 500 600 300 500 400 400 400 400 500 90 90
Maximum adult or pediatric weight-based dose (mg/kg) 7.0 9.0 4.5 7.0 6.6 6.6 6 6 7 1.3 1.3
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block. Other relative contraindications include an uncooperative patient, such as an anxious adult, scared child, or any patient with altered mental status. These patients place themselves and the Emergency Physician at significant risk for injury. It may be most prudent to abort the procedure and perform procedural sedation and analgesia (or general anesthesia in the operating room) to ensure the safety of the patient and the Emergency Physician. The needle used to inject local anesthetic solution should not traverse infected tissue. Injection of the local anesthetic solution into or through infected tissue is also a relative contraindication. These processes may result in spread of the infection into other adjacent tissues or tissue planes. It is possible to cause bacteremia when injecting into infected tissues. Local anesthetic solutions are less effective when injected into areas of infection or inflammation. An infection that tracks along a nerve and into a bone of the face and/or skull is extremely difficult to treat. Evaluate the risks and benefits of injecting through infected tissue and attempt an alternative method of anesthesia if possible.
EQUIPMENT • Nonsterile gloves • Antiseptic mouth rinse, any of the following: ▶ Hydrogen peroxide ▶ Ethanol (7%) with chlorhexidine (0.5%) ▶ Povidone iodine solution ▶ 0.12% chlorhexidine or Peridex solution • 4 × 4 gauze squares • Cotton-tipped applicators • Aspirating dental syringe (Figure 176-2) • Local anesthetic solution (Table 176-1) • Syringes, 1 and 3 mL • Suction source and tubing • Yankauer suction catheter • Topical anesthetic (e.g., viscous lidocaine, viscous benzocaine, or aerosolized benzocaine) • Overhead light source or headlamp • 22 to 27 gauge needles, 2 inches long The above-listed supplies are required to provide dental anesthesia. They are contained in every Emergency Department. An aspirating dental syringe and anesthetic cartridges, if available, are ideal to perform the nerve blocks (Figure 176-2). Standard 1 to 3 mL syringes armed with a 25 or 27 gauge, 2 inch long needle will work as a substitute. The aspirating dental syringe allows better control of the syringe and the ability to simultaneously aspirate and insert the needle with one hand. This allows the nondominant hand to be used to identify landmarks, retract the cheek or tongue, adjust the light source, and/or use the suction catheter. Many local anesthetic solutions are available in 1.8 mL carpules that fit into the dental aspirating syringe. The carpules are available with the local anesthetic solution, and also with or without a vasoconstrictor (usually epinephrine). A dental or multipositional procedure chair would be preferred to the use of a standard cart or gurney.2,3 Unfortunately, this may not be available in many Emergency Departments. Numerous injectable agents are available to provide anesthesia (Table 176-1). The most commonly used agents are lidocaine and lidocaine without epinephrine (1:100,000). Longer acting agents are commonly available in the Emergency Department (e.g., bupivacaine and mepivacaine, with and without epinephrine) when a prolonged period of anesthesia is required. Avoid using long-acting
FIGURE 176-2. The aspirating dental syringe and local anesthetic cartridges.
local anesthetic agents if the tongue (i.e., inferior alveolar or lingual nerve blocks) or mucosa (i.e., buccal nerve block) is anesthetized, especially in children, to prevent the patient from biting the area and causing injury. A relatively new device is the Accupal (Accupal, Little Rock, AR). It is an injection preparation tool that prepares the gums before the anesthetic needle is inserted. The Accupal vibrates and produces ultrasonic tissue stimulation to reduce pain sensation at the needle injection site. The Accupal is usually not available in the Emergency Department. Numerous jet injectors for the delivery of local anesthetic agents are commercially available. These devices inject the local anesthetic solution under pressure and in a fine stream into the soft tissues without the use of a needle. The small volume of injected solution and its superficial penetration into the soft tissues only anesthetizes the soft tissues and not the teeth. Thus, jet injectors cannot be used to anesthetize teeth. They can be used to provide topical anesthesia.
PATIENT PREPARATION Perform a thorough history and a directed physical examination, dependent on the clinical situation, in any patient undergoing dental anesthesia. Give special attention to the past medical history, past surgical history, current medications, and any history of allergic or adverse reactions to an anesthetic agent. A patient with severe systemic disease may be better served by rescheduling the procedure after appropriate consultation or referral. This will clarify functional reserve and treatment limitations.2,3 Any patient with cardiac valvular disease, congenital heart anomalies, artificial heart valves, or other indications should receive antibiotic prophylaxis to help prevent bacterial endocarditis caused from transient bacteremia. Please refer to Chapter 177 for more complete details of antibiotic prophylaxis. Explain the procedure, its risks, and benefits to the patient and/ or their representative. Obtain an informed consent for the specific
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technique to be performed. A formal consent may exist depending upon the institution in which one practices. Some physicians desire a formal signed and dated consent form. Other physicians choose to chart: “All the risks, benefits, and complications were described and discussed with the patient. They understood the procedure described and gave verbal consent for the procedure.” This is physician and institution dependent. Place the patient in a well-lighted environment. Reassurance often alleviates a patient’s anxiety regarding injections or manipulations and puts them at ease.2 Prepare the mucosa at the injection site. Completely dry the mucosa with gauze squares. Apply an antiseptic solution (e.g., 7% ethyl alcohol (ETOH) with 0.5% chlorhexidine solution, diluted povidone iodine, 0.12% chlorhexidine solution, or hydrogen peroxide) to the working area with a cotton ball or gauze square for 15 seconds. Alternatively, the patient can swish 0.12% chlorhexidine mouth rinse or hydrogen peroxide for 30 seconds and then spit it out. Apply a topical anesthetic agent (e.g., viscous lidocaine or benzocaine with a cotton-tipped applicator, or 20% benzocaine spray) for added patient comfort. It is not recommended to use TAC (tetracaine, adrenalin, and cocaine) or other topical anesthetic combinations that are used for cutaneous laceration repair on mucosal surfaces. Their use may lead to significant absorption and systemic toxicity.
TECHNIQUES The general procedure of a dental nerve block will be described. The specific details are contained within each nerve block described below. Identify the anatomic landmarks required to perform the nerve block. Clean the mucous membrane at the injection site with a gauze square. Apply an antiseptic solution. Apply a topical anesthetic and allow it to work for 2 to 3 minutes. Reidentify the anatomic landmarks. Insert a 25 or 27 gauge needle into the appropriate area to deliver the local anesthetic agent. If the patient experiences paresthesias, do not inject the local anesthetic solution. Paresthesias signify that the tip of the needle is within the nerve bundle. Withdraw the needle 1 to 2 mm and allow the paresthesias to resolve. This usually takes 5 to 20 seconds. Inject the local anesthetic solution. Allow up to 10 minutes for the local anesthetic solution to take effect. Some Dentists prefer to apply pressure to the area immediately next to the site of the anesthetic injection with a cotton-tipped applicator. This aids in distracting the patient from the pain of injection. Other Dentists “jiggle” the mucous membrane to and fro rapidly as they simultaneously introduce the needle.2,3
SUPRAPERIOSTEAL INFILTRATION (FIELD BLOCK) This technique is commonly used in dentistry. Excellent anesthesia can be achieved with this technique when it is used to anesthetize a branch of the anterior or middle superior alveolar nerve.3,4 This technique deposits local anesthetic agent against the periosteum of the alveolar ridge adjacent to a tooth (Figure 176-3A). The local anesthetic agent then infiltrates through the periosteum, the cortical plate of the maxilla, and the medullary bone to anesthetize the nerve root as it leaves the apex of the tooth. This technique works best for teeth with associated thin cortical bone. This includes the maxillary incisor, canine, and premolar teeth. The molars of the maxilla in an adult are less likely to be anesthetized with this technique as the cortical bone in which they lie is relatively thick and a poor conduit for the anesthetic. Supraperiosteal infiltration is also a poor technique for anesthesia of mandibular teeth in the adult patient for the same reasons. In children, the cortical bone of the maxillary molars and the mandible is thin and may allow this technique to be effectively utilized to anesthetize a tooth.
FIGURE 176-3. Supraperiosteal infiltration of local anesthetic solution. A. Illustration of the correct needle position. B. Elevate the upper lip and insert the needle through the mucobuccal fold.
Anatomy The anterior superior alveolar nerve provides sensory
innervation to the ipsilateral medial and lateral incisors, canine, and sometimes the first premolar teeth. The middle superior alveolar nerve provides sensory innervation to the ipsilateral premolars, canine, and first molar teeth. Patient Positioning Place the patient recumbent in a dental chair with their neck extended 45°. Alternatively, position the patient sitting upright with their back and head firmly set against an examination chair or table. Landmarks Use the nondominant hand to grasp and pull the upper lip outward and upward (Figure 176-3B). Identify the mucobuccal fold above the tooth to be anesthetized.3 Needle Insertion and Direction Clean, prep, and apply a topical anesthetic agent to the mucobuccal fold above the tooth to be anesthetized. Firmly grasp the upper lip. Pull it outward and upward to tighten the tissues and allow a clear identification of the maxillary mucobuccal fold (Figure 176-3B). Insert a 27 gauge needle through the mucobuccal fold over the center of the tooth to be anesthetized (Figure 176-3B). Aim the tip of the needle toward the maxilla. Advance the needle 1.0 to 1.5 cm until it contacts the maxilla (Figure 176-3A). Withdraw the needle 1 mm. Aspirate to confirm that the tip of the needle is not within a blood vessel. Inject 1 to 2 mL of local anesthetic solution. Remarks The anesthetic will be deposited in a nonoptimal location if the needle is too deep or too shallow. It may take as long as 10 minutes to achieve anesthesia as the local anesthetic solution diffuses through the cortical bone and to the nerve root. Be careful when using this technique for anesthesia of the incisor or canine
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FIGURE 176-6. The intraoral approach to the infraorbital nerve block. A. Location of the nerve. B. Insertion of the needle. FIGURE 176-4. The supraorbital foramen, infraorbital foramen, and the mental foramen all lie along a straight line drawn through the pupil in the midposition.
teeth because advancing the needle too far may breach the nasal cavity or maxillary sinuses.
INFRAORBITAL NERVE BLOCK Anatomy The infraorbital nerve is the terminal branch of the maxil-
lary nerve. It exits the maxilla via the infraorbital foramina and supplies sensation to the ipsilateral upper lip, cheek, lateral nose, and lower eyelid. It may be blocked by either an extraoral or intraoral approach. Patient Positioning Place the patient recumbent in a dental chair with their neck extended 30°. Alternatively, position the patient sitting upright with their head and back against an examination chair or table with their neck extended 30°. Instruct the patient to slightly open their mouth. Landmarks Identify the infraorbital foramen by palpation. It is located below the infraorbital ridge in the midpupillary line (Figure 176-4). The midpupillary line is a line drawn in the sagittal plane (vertical) through the pupil while the patient is staring straight ahead. Needle Insertion and Direction (Extraoral Approach) Identify the infraorbital foramen as above. Clean and prep the skin over the infraorbital foramen. Instruct the patient to close their eyes. Insert a 25 or 27 gauge needle through the skin overlying the infraorbital foramen (Figure 176-5). Advance the needle to just beneath the
FIGURE 176-5. The extraoral approach to the infraorbital nerve block. A. Location of the nerve. B. Insertion of the needle.
subcutaneous tissue. Do not enter the infraorbital canal as this may damage the nerve. Aspirate to confirm that the tip of the needle is not within a blood vessel. Inject 1 to 2 mL of local anesthetic solution. Massage the area over the infraorbital foramen for a few seconds to ensure optimal infiltration. Needle Insertion and Direction (Intraoral Approach) Clean, prep, and apply a topical anesthetic agent to the mucosa opposite the first maxillary premolar. Place the nondominant index finger over the infraorbital foramen (Figure 176-6). Retract the upper lip using the nondominant thumb. Identify the mucobuccal fold above the first premolar. Insert a 25 or 27 gauge needle through the mucobuccal fold. Advance the needle toward the nondominant index finger situated over the infraorbital foramen (Figure 176-6B). Stop advancing the needle when the tip is felt beneath the index finger. The estimated depth of penetration of the needle tip is 1.0 to 1.5 cm in an older child or an adult and 0.5 to 1.0 cm in a younger child. Aspirate to confirm that the tip of the needle is not within a blood vessel. Inject 1 to 2 mL of local anesthetic solution. Remarks Be careful not to penetrate too deeply when performing the intraoral approach. The infraorbital venous plexus may be disrupted and result in a hematoma. The globe may also be accidentally penetrated. Avoid these complications by positioning the nondominant index finger over the infraorbital foramen and using it to palpate and track the advancing needle tip. The intraoral approach is the preferred technique.
NASOPALATINE NERVE BLOCK Anatomy The nasopalatine nerve provides sensory innervation to the anterior one-third of the hard palate (Figure 176-7A). It exits the maxilla via the incisive foramen in the midline and 0.5 cm posterior to the central incisors. Patient Positioning Place the patient recumbent in a dental chair with their head extended 45°. Alternatively, place the patient supine with a rolled sheet beneath their shoulder blades to assist in neck extension. Instruct the patient to fully open their mouth. Landmarks The incisive foramen lies in the midline and approximately 5 mm posterior to the central incisors of the maxilla. Overlying the incisive foramen is the incisive papilla, a soft tissue elevation. Needle Insertion and Direction Clean, prep, and apply a topical anesthetic agent to the mucosa on the anterior one-third of the hard palate. Identify the incisive foramen by first identifying the incisive papilla. Insert a 27 to 30 gauge needle, with the bevel facing the hard palate, from a position immediately lateral to the edge of the incisive papilla (Figure 176-7B). Advance the needle
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FIGURE 176-7. Anesthesia of the palate. A. Sensory innervation of the palate. B. Nasopalatine nerve block. C. Greater palatine nerve block.
3 to 4 mm toward the midline or until bone is identified. Aspirate to confirm that the tip of the needle is not within a blood vessel. Inject 0.25 to 0.35 mL of local anesthetic solution. The area surrounding the injection site will blanch upon deposition of the local anesthetic solution.2,3 Remarks This is a particularly painful injection due to the adher-
ent nature of the mucosa to the underlying hard palate. Topical anesthetics will provide adequate preinjection anesthesia. Some clinicians use a cotton-tipped applicator or a blunt instrument to put pressure on the incisive papilla for 30 seconds prior to and during the injection.3 This seems to defer the attention of the patient and make the injection more bearable. Be careful not to penetrate too deeply with the needle and enter the incisive foramen. Insertion into the incisive foramen will cause severe pain. Injection into the incisive foramen can result in permanent nerve damage.2,3 The mucosa of the hard palate receives its blood supply from the hard palate. Injection of more than 0.4 mL will elevate the mucosa from the hard palate and result in mucosal necrosis. This block may be performed to repair lacerations of the mucosa of the anterior hard palate.
GREATER PALATINE NERVE BLOCK Anatomy The greater palatine nerve provides sensory innerva-
tion to the ipsilateral posterior two-thirds of the hard palate (Figure 176-7A). It enters the oral cavity via the greater palatine
foramen. The greater palatine foramen lies between the second and third maxillary molar and approximately 1 cm onto the hard palate. Patient Positioning Place the patient recumbent in a dental chair with their head extended 45°. Alternatively, place the patient supine with a rolled sheet beneath their shoulder blades to assist in neck extension. Instruct the patient to fully open their mouth. Landmarks The greater palatine foramen lies 1 cm medial to the gingival junction of the second and third maxillary molar (Figure 176-7C). Needle Insertion and Direction Clean, prep, and apply a topical anesthetic agent to the hard palate adjacent to the second and third maxillary molars. Insert a 27 to 30 gauge needle 1 cm medial to the junction of the second and third maxillary molars (Figure 176-7C). Ensure that the tip of the needle is held at 90° to the curve of the palate. Aspirate to confirm that the tip of the needle is not within a blood vessel. Inject 0.25 to 0.35 mL of local anesthetic solution. The area surrounding the injection site will blanch upon deposition of the local anesthetic solution.2,3 Remarks This block may be performed to repair lacerations of the mucosa of the hard palate. The mucosa of the hard palate receives its blood supply from the hard palate. Injection of more than 0.4 mL will elevate the mucosa from the hard palate and result in mucosal necrosis. The position of the lesser palatine foramen is 2 to 4 mm posterior to the greater palatine foramen. The lesser palatine nerve provides sensory innervation to the soft palate and uvula. If anesthetized, as it often is when blocking the greater
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palatine nerve, the patient may experience a feeling of dysphagia or throat closure. Reassurance is usually adequate to alleviate the patient’s anxiety until the anesthesia wears off.
POSTERIOR SUPERIOR ALVEOLAR NERVE BLOCK Anatomy The maxillary nerve exits the skull via the foramen rotun-
dum. It then courses anteriorly into the pterygopalatine fossa and divides into its constituent branches. The posterior superior alveolar nerve provides sensory innervation to the maxillary molar teeth and their associated mucosal tissues. Patient Positioning Place the patient semirecumbent in a dental chair with their head extended 30°. Alternatively, place the patient sitting upright with their head and back firmly against the examination chair or table and their head extended 30° to 45°. Instruct the patient to fully open their mouth. Landmarks Pull the buccal mucosa laterally and identify the inferior-most posterior portion of the zygoma. It lies posterior, lateral, and superior to the third maxillary molar. The pterygomaxillary fissure lies posterior, medial, and superior to the vestibule between the third maxillary molar and the posterior zygoma. The pterygopalatine fossa can be reached by following the pterygomaxillary fissure superiorly and medially.2,3 Needle Insertion and Direction Clean, prep, and apply a topical anesthetic agent to the recess posterior and lateral to the maxilla. Insert the nondominant index finger between the maxillary molars and the cheek (Figure 176-8A). Palpate the zygomatic process of the maxilla with the index finger. Rotate the index finger 180° so that the pad is against the patient’s cheek (Figure 176-8B). Apply outward pressure to move the cheek away from the teeth. Place the needle along the middle of the nail plate of the index finger. Aim the needle and syringe along the index finger (Figure 176-8B). The needle and syringe should be aimed posteriorly, superiorly, and medially (Figure 176-8C). Insert and advance the needle 2.5 cm along the index finger. If the needle contacts bone, withdraw the needle completely and direct it more laterally.2,3 Aspirate to confirm that the tip of the needle is not within a blood vessel. Inject 3 mL of local anesthetic solution. Remarks Bend the needle 30° at the hub to assist in achieving a medial direction of the needle. Do not bend the needle more than 30° as the needle may fracture. It is extremely important to never change the direction of a needle once it is inserted. This is associated with an increased risk of needle breakage requiring an operative procedure to recover the needle segment. Never force the needle. The needle is inappropriately positioned if it is meeting resistance. Abort the procedure, reidentify the landmarks, and reattempt the procedure.2,3 Occasionally, the first molar is only partially anesthetized by this block. Consider supplementation of this block with a supraperiosteal infiltration of the first molar.
MENTAL NERVE BLOCK, INTRAORAL APPROACH Anatomy The mental nerve is one of the two terminal divisions of
the inferior alveolar nerve. It provides sensory innervation to the ipsilateral skin and mucosa of the lower lip and chin. It exits the bony mandible at the mental foramen. Patient Positioning Place the patient recumbent in a dental chair. Alternatively, place the patient sitting upright or supine with their head against the examination table and in the neutral position. Instruct the patient to slightly open their mouth. Landmarks The mental foramen lies in the same plane as the infraorbital foramen and the midpupillary line (Figure 176-4). The
FIGURE 176-8. The posterior superior alveolar nerve block. A. The nondominant index finger is inserted and positioned. B. The cheek is retracted. C. The proper direction for insertion and advancement of the needle.
mental foramen is located approximately 1 cm beneath the gum line, between the first and second premolar. Needle Insertion and Direction Clean, prep, and apply a topical anesthetic agent to the oral mucosa overlying the mental foramen. Grasp the lower lip with the nondominant hand. Pull it outward and downward (Figure 176-9). Insert a 27 gauge needle into the mucobuccal fold between the first and second premolar (Figure 176-9). Advance the needle medially until it contacts the mandible. Aspirate to confirm that the tip of the needle is not within a blood vessel. Inject 1.5 to 2.0 mL of local anesthetic solution. Remarks The mental nerve block, as the infraorbital nerve block, has an intraoral and an extraoral approach. The extraoral approach will not be discussed as it is more painful and there is no benefit to its use over the intraoral approach. A description of the extraoral
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FIGURE 176-9. The intraoral approach to the mental nerve block.
approach to the mental nerve block is found in Chapter 126. A near midline lower lip or chin injury may necessitate bilateral mental nerve blockade due to the midline crossover from each of the mental nerves.2
BUCCAL NERVE BLOCK Anatomy The buccal nerve is one of the main branches of the man-
dibular nerve. It travels down the medial aspect of the ramus of the mandible, anterior to the inferior alveolar neurovascular bundle. It crosses from the medial mandible into the soft tissue of the cheek at the level of the occlusive plane. It supplies the sensory innervation to the mucous membrane of the cheek and vestibule.1 It innervates, to a variable degree, a small patch of skin over the cheek. Patient Positioning Place the patient recumbent in a dental chair with their head extended 30°. Alternatively, place the patient sitting with their head and back firmly against an examination chair or upright table with their head extended 30° to 45°. Instruct the patient to fully open their mouth. Landmarks Visually identify the third mandibular molar. Palpate the anterior border of the ramus of the mandible. The buccal nerve traverses the anterior border of the ramus of the mandible, posterior and slightly lateral to the third molar at the level of the occlusive plane. Needle Insertion and Direction Clean, prep, and apply a topical anesthetic agent to the oral mucosa over the anterolateral border of the ramus of the mandible. Place the thumb of the nondominant hand on the inner surface of the cheek. Pull the cheek outward. Insert a 27 gauge needle 1 mm lateral to the anterior border of the ramus of the mandible and at the level of the occlusal plane (Figure 176-10). Advance the needle 3 to 4 mm into the soft tissues. Aspirate to confirm that the tip of the needle is not within a blood vessel. Inject 2 mL of local anesthetic solution. Remarks Buccal nerve blocks are used when extensive intraoral manipulation is anticipated, when buccal manipulation or repair is required, or for the incision and drainage of an abscess. It provides additional patient comfort. The block is nearly always performed as an adjunct to an inferior alveolar, maxillary, or posterior superior alveolar nerve block.3
FIGURE 176-10. The buccal nerve block.
INFERIOR ALVEOLAR NERVE BLOCK Anatomy The lingual and inferior alveolar nerves are two of four
branches of the mandibular nerve. The nerves initially travel together and inferiorly on the medial side of the mandibular ramus (Figure 176-11A). The lingula is a palpable bony landmark immediately anterior to the mandibular foramen. The inferior alveolar nerve courses posterior to the lingula and enters the mandibular canal via the mandibular foramen. It continues to travel anteriorly within the mandible to provide sensory innervation to the body of the mandible, the mandibular teeth, and the overlying oral mucosa. One of the terminal branches of the inferior alveolar nerve is the mental nerve. The inferior alveolar nerve may be blocked by the classic, open-mouth approach or the closed-mouth approach. Patient Positioning Place the patient in a dental chair with their head neutral, such that the occlusive surface is parallel to the floor. Alternatively, place the patient sitting upright in an examination chair or on a gurney with their head positioned firmly against the back of the gurney or chair. Instruct the patient to fully open their mouth. Perform the open-mouth approach if the patient can fully open their mouth. Perform the closed-mouth approach if the patient has trismus or cannot fully open their mouth. Landmarks Identify by palpation the anterior border of the ramus of the mandible within the mouth, the coronoid notch within the mouth, and the posterior border of the ramus of the mandible externally (Figure 176-11B). Approximately equidistant from these two points lie the lingual and the inferior alveolar nerves. Palpate the lingula of the ramus of the mandible. It is a bony projection on the medial surface of the ramus of the mandible and 1 cm above the occlusive plane. Needle Insertion and Direction (Open-Mouth Approach) Clean, prep, and apply a topical anesthetic agent to the inner surface of the ramus of the mandible. Stand opposite the side to be blocked. Place the thumb of the nondominant hand on the anterior border of the ramus of the mandible. Move the thumb posteromedially to identify the lingula. Place the index finger of the nondominant hand against the extraoral border of the mandibular ramus, just above the angle of the mandible. Grasp the ramus between the thumb and
CHAPTER 176: Dental Anesthesia and Analgesia
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FIGURE 176-11. The inferior alveolar nerve block. A. The course of the inferior alveolar nerve and the lingual nerve along the ramus of the mandible. B. The anatomy of the external surface of the mandible. C. Positioning for the open-mouth approach. D. Proper needle insertion and direction for the open-mouth approach. E. The closedmouth approach. F. Superior view of the closed-mouth approach demonstrating the proper needle direction.
the forefinger (Figure 176-11C). Pull the cheek outward using the nondominant thumb as a lever. Place a 27 gauge, 2 inch needle on a 3 mL syringe that contains local anesthetic solution. A 5 mL syringe is too large for this approach. A syringe smaller than 3 mL will not carry enough anesthetic.
Introduce the needle from the opposite side (Figure 176-11D). Align the tip of the needle toward the lingula with the barrel of the syringe between the contralateral first and second premolars (Figure 176-11D). Hold the syringe parallel to the occlusal plane and 3 to 4 mm above the premolars. Insert the needle into the oral
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mucosa just superior and posterior to the lingula. Advance the needle until the tip contacts the ramus of the mandible. Aspirate to confirm that the tip of the needle is not within a blood vessel. Inject 2 mL of local anesthetic solution. The above technique is optimal if the operator is right-handed and a right-sided inferior alveolar block is attempted. If the operator is right-handed and attempting a left-sided inferior alveolar nerve block, it is still necessary to stand opposite the side to be anesthetized with the syringe in the dominant hand. Place the nondominant arm over and around the patient’s head so that the thumb of the nondominant hand can contact the anterior border of the mandibular ramus and the index finger can grasp the posterior border above the angle of the mandible. The remainder of the technique is the same. Needle Insertion and Direction (Closed-Mouth Approach) This method can be used when the patient cannot fully open their mouth due to an abscess, edema, mandible fractures, trismus, or if the mandible is wired-closed to the maxilla. This approach deposits the local anesthetic solution superior to the site of the classic, open-mouth approach. The local anesthetic solution will descend, due to gravity, to bathe the inferior alveolar nerve and provide adequate anesthesia. Place the nondominant thumb on the inner surface of the cheek. Pull the cheek outward. Place a 27 gauge needle on a 3 mL syringe that contains local anesthetic solution. Place the needle and syringe parallel to the occlusal plane and aligned along the junction of the maxillary molars and their gingiva (Figure 176-11E). Direct the needle just medial to the ramus of the mandible (Figures 176-11E & F). Advance the needle 3 cm through the mucosa. Aspirate to confirm that the tip of the needle is not within a blood vessel. Inject 2 mL of local anesthetic solution. Remarks It is crucial that the tip of the needle contacts the mandible in the open-mouth approach. The needle is usually advanced 0.5 to 1 cm before the mandible is encountered. The needle is most likely inappropriately placed and deposition of anesthesia will not produce the desired results if the mandible is not encountered. Remove the needle, reidentify the appropriate anatomic landmarks, and reattempt the procedure if the mandible is not encountered. The buccal, inferior alveolar, and lingual nerves must be blocked on one side to achieve complete anesthesia of the hemimandible. Facial nerve paralysis can occur if the needle is inserted too far posterior and enters the capsule of the parotid gland. This paralysis is usually transient and resolves as the anesthetic wears off.
LINGUAL NERVE BLOCK Anatomy The lingual nerve is a branch of the mandibular division of
the trigeminal nerve. It travels with the inferior alveolar nerve until the inferior alveolar nerve enters the mandible. The lingual nerve leaves the medial aspect of the mandibular ramus and penetrates the posterior tongue at the level of the occlusive plane, just medial to the third mandibular premolar. It courses anteriorly to provide sensory innervation to the anterior two-thirds of the tongue, the floor of the mouth, and the lingual mucous membrane.1 Patient Positioning Place the patient in a dental chair with their head neutral, such that the occlusive surface is parallel to the floor. Alternatively, place the patient sitting upright in an examination chair or on a gurney with their head firmly against the back of the gurney or chair. Instruct the patient to fully open their mouth. Landmarks Identify the lingual side of the second mandibular molar. The injection site is 1 cm medial to the second mandibular molar. Needle Insertion and Direction Approach the patient from the contralateral side. Move the tongue upward or toward the contralateral
FIGURE 176-12. The lingual nerve block.
side with a tongue blade. Insert a 27 gauge, 2 inch needle into the mucosa 1 cm medial to the second mandibular premolar (Figure 176-12). Advance the needle posteriorly 1 cm. Aspirate to confirm that the tip of the needle is not within a blood vessel. Inject 1.0 to 1.5 mL of local anesthetic solution. Remarks The inferior alveolar nerve and the lingual nerve can be, and usually are, blocked simultaneously during an inferior alveolar nerve block. The lingual nerve, however, can be blocked in an isolated fashion. Perform an isolated lingual nerve block only when the initial combined block has failed or for isolated tongue lacerations.1,3 This is an optimal block for tongue laceration repair. However, bilateral lingual nerve blocks may be necessary.
ASSESSMENT Anesthesia is usually achieved within 5 minutes of the injection. However, depending upon the particular injection and the local anesthetic used, anesthesia can be achieved anywhere from 20 seconds to 10 minutes. The block was properly performed if the patient experiences anesthesia. Repeat the block if anesthesia is not achieved by 10 minutes.
AFTERCARE The aftercare of dental anesthesia is minimal. Reexamine the area of the local anesthetic injection before the patient is discharged to ensure that a hematoma has not developed. Instruct the patient to use caution as there is no sensation in the area anesthetized. Encourage them to refrain from meals, chewing gum, hot beverages, aggravated scratching, placing foreign bodies in the mouth, or anything that may cause injury to the anesthetized area. Parents must be informed to discourage children from testing the anesthetized area by biting or chewing. Many Dentists and Physicians place a cotton roll, or rolled 2 × 2 gauze, between the area anesthetized and the teeth to provide added protection from a self-inflicted bite injury.2,3
COMPLICATIONS Any patient receiving dental anesthesia has the potential to develop complications. The key is to have knowledge of these complications and be prepared to deal with them should they occur. Most severe complications will declare themselves in a rapid fashion. These severe complications include intravascular injection of local
CHAPTER 177: Dental Abscess Incision and Drainage
anesthetic, allergic reactions to the local anesthetic, cardiovascular toxicity, neurologic toxicity, seizures, and unintentional overdosage. Allergic reactions can occur from the latex vial/carpule seal or the preservative in the local anesthetic.5 These complications can be avoided by aspiration before injection, obtaining an appropriate history of prior anesthesia, and cautious calculation of anesthetic dosages, respectively.2–4 Late complications of dental anesthesia include hematomas, neuropathy, infection, and trismus.2,3 Hematomas after dental anesthesia occur after the inadvertent puncture of an artery or vein. Arterial hematomas enlarge more rapidly and are usually more painful than venous hematomas. They can cause a significant facial deformity. Hematomas following dental anesthesia are usually of little significance, require no intervention, and resolve spontaneously with time. A proper preprocedural history should determine if the patient is using anticoagulants or blood thinners, has a real or potential bleeding disorder, or had adverse bleeding complications from previous procedures. Treatment initially involves applying cold packs. Heat in the form of an externally placed heating pad should be used to help disintegrate the clot after 24 hours.2,3 A peripheral neuropathy can occur in the form of prolonged anesthesia, paresthesias (burning or itching sensation), hyperesthesias (increased sensitivity to noxious stimuli), and dysesthesias (painful sensation to non-noxious stimuli). This may be a result of direct damage to the nerve from traumatic needle insertion, hemorrhage or hematoma within the nerve sheath, deposition of local anesthetic into a foramen or canal causing pressure injury to the nerve, or chemical injury to the nerve.6,7 Reduce the risk of causing a neuropathy by avoiding injections into a foramen, using a small gauge needle, and withdrawing the needle slightly before injection if the patient should feel a shock or paresthesias with needle insertion.2,3 While many nerve injuries are temporary and will resolve with time, some can be permanent.7 Infection due to dental anesthesia is rare, but does exist. Follow several simple measures to minimize potential infections. Never inject through an infected area. Doing so may carry bacteria through facial planes into deeper compartments. Refrain from multiple injections (needle misadventures) as this increases the risk of iatrogenic infection. This is easily resolved by appropriately identifying the anatomic landmarks prior to needle insertion. Needle breakage can occur as a result of manufacturing defects or operator imprudence. To prevent needle breakage, never exert force against resistance. Resistance signifies that the tip of the needle is against bone or a tooth. Withdraw the needle and reattempt insertion if this occurs. Never advance the needle to the hub. The greatest percentage of needle breaks occur when the needle is inserted to the hub.2,3 Never redirect the needle after it is inserted through the skin or mucosa. This puts abnormal force on the needle and potentiates breakage. The needle may inadvertently be in an undesired anatomic location. Withdraw the needle completely, identify the appropriate anatomic landmarks, and reinsert the needle. Do not bend the needle as this can weaken it and make it more prone to breakage. If a needle breaks, grasp the fragment with a forceps or hemostat and remove it from the soft tissue. If the needle fragment is not palpable with an instrument, consult a Dentist or Oral Surgeon for possible removal. The consultant may choose to see the patient in the Emergency Department, see the patient in their office within 24 to 48 hours, or leave the needle fragment in place and not remove it.
SUMMARY Dental anesthetic techniques are easy to learn, simple to perform, and effective in providing temporary pain relief. The required equipment is readily available in every Emergency Department.
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Consider using local anesthetic agents that contain epinephrine because they provide significantly longer analgesia than those without epinephrine. A rapidly performed local anesthetic injection goes a long way toward patient satisfaction.
177
Dental Abscess Incision and Drainage Daniel J. Ross
INTRODUCTION Patients frequently present to the Emergency Department complaining of a “toothache”. The common causes of toothache pain are multiple.1 Similarly, there are multiple etiologies for a dental abscess (Table 177-1). Distinguishing the type of dental abscess can have an impact upon treatment decisions, prognosis, and patient morbidity.2–5 The accurate diagnosis and proper treatment of these maladies require that the Emergency Physician has a basic understanding of dental anatomy, pathophysiology, and simple dental treatment protocols. Many of these conditions can be managed initially through the Emergency Department. The prudent Emergency Physician must have a clear understanding that these infections can rapidly become complicated and may require timely consultation or referral.
ANATOMY AND PATHOPHYSIOLOGY Teeth are essentially composed of three layers (Figure 177-1). These layers, from the outside working inward, are the enamel, the dentin, and the pulp. The dentin and pulp are living tissues that are sensitive to noxious stimuli. The crown is covered with enamel, while the root is covered with a substance known as cementum. Cementum helps attach the tooth to the surrounding alveolar bone via the periodontal ligament (PDL). The neurovascular supply enters the pulp through the apical foramen at the root apex. The pulp contains only pain transmitting neuronal fibers, while the PDL contains both pain-sensitive and pressure-sensitive fibers.7 Dental abscesses arise when bacteria penetrate the normal anatomic and physiologic barriers of the tooth and surrounding structures. This can lead to a localized collection of purulence contained within the tooth (pulpal abscess), or around the apex of the tooth (periapical abscess) (Figure 177-2). Alternatively a dental abscess may localize to the supporting structures of the tooth (periodontal abscess) or strictly to the adjacent soft tissues (pericoronitis) (Figure 177-2).
PULPAL OR PERIAPICAL ABSCESSES Dental abscesses often arise from pulpal necrosis secondary to dental caries or a defective restoration.1,3,4,6,7 Dental caries is commonly known as dental decay or “cavities”. This is the direct destruction
TABLE 177-1 Common Etiologies for a Dental Abscess Cysts that become infected Gingival infections Mixed periodontal/periapical infections Periapical infections Periodontal infections Postoperative infections Root fracture that becomes infected
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FIGURE 177-1. The anatomy of a tooth.
of the tooth substance by the acidic bacterial products of normal oral flora. A carious tooth may not initially be painful. The products of inflammation eventually reach the dental pulp as the disease process progresses and the tooth will become sensitive.1–3,7–9 This is known as pulpitis. Patients will report nonlocalizable and intermittent symptoms. This process may initially be reversible by routine dental treatment (e.g., a filling), but the pulp will rapidly necrose and die if it becomes infected. If the infectious process is allowed to continue, products from the necrotic pulp may escape the confines of the tooth via the apical foramen and begin to involve the PDL and
FIGURE 177-2. Locations of common dental abscesses.
surrounding alveolar bone. This is known as a periapical abscess, and makes the infected tooth easily localizable by patient complaints of spontaneous or constant sensitivity, and/or tenderness to gentle percussion.1–3,5–7,9 The infection could likely be halted at this stage of the pathophysiologic process with a “root canal,” which is essentially an incision and drainage procedure performed on the inside of a tooth by an Endodontist.6,7 If left unchecked, however, the bacterial products of a periapical infection and the host’s immune response to it can lead to a progressive destruction of the dental supporting tissues, including the alveolar bone. At this point the tooth will become increasingly mobile. The infection will follow the path of least resistance as it penetrates through the alveolar bone into the surrounding soft tissues.6,7 It may perforate laterally to form a vestibular abscess (Figure 177-3A). Alternatively, it may perforate medially to form a palatal or lingual abscess (Figure 177-3B). Further spread will be dictated by the proximity of the muscle attachments and fascial planes.3,5–7,9–11 The appropriate treatment for an abscessed tooth depends on the extent of infection. It may include endodontic treatment, incision and drainage, extraction, or a combination of these.6,7 An incision and drainage procedure is warranted if the infectious process extends outside the alveolar bone and involves the soft tissues.5,6,7,9,10 The extension of infectious products outside the root apex can lead to a multitude of clinical signs throughout the head and neck. Swelling, erythema, warmth, fluctuance, and spontaneous drainage of purulence via a sinus tract or fistula may be seen intraorally or extraorally. A localized or generalized cellulitis may be present. There is often a foul breath odor.1,5,6,10 One or more of the numerous named fascial spaces of the head and neck may become involved via direct extension.3,5–8,10–16 Systemic symptoms may become involved including fever, malaise, anorexia, and leukocytosis.5,6,8,10,12 Structures immediately adjacent to the oral cavity may become involved. This can result in trismus, reactive sinusitis, lymphadenopathy, osteomyelitis, cavernous sinus thrombosis, airway compromise, and/or a brain abscess.3,11–16 Dental infections extending into any of the fascial compartments of the head and neck are dangerous, can rapidly progress, and are
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FIGURE 177-3. The spread of a dental abscess. A pulpal abscess progresses to a periapical abscess that perforates the alveolar plate. A. Labial or buccal perforation leads to a vestibular abscess. B. Palatal or lingual perforation leads to a palatal or lingual abscess, respectively.
considered complicated infections.3,5–7,10,12–16 Patients typically have a toxic appearance with systemic signs and symptoms. They often present with dysphagia, dysphonia, or dyspnea. The classic example is Ludwig’s angina or a concurrent bilateral involvement of the sublingual, submental, and submandibular spaces. This represents an immediate threat to the airway.11,13,15,16 Infectious extensions into the lateral pharyngeal, retropharyngeal, and prevertebral spaces are rare and can lead to disastrous complications such as aspiration, mediastinitis, and airway compromise. A retropharyngeal space measuring greater than 3 to 5 mm on lateral soft tissue neck radiographs or CT scans is indicative of airway compromise.10 Consider rapid and aggressive management with prompt surgical consultation, broad-spectrum antibiotics, and early airway intervention in patients who are suspected of manifesting any of these processes.3,8,10–15
PERIODONTAL ABSCESSES Poor dental hygiene and poor nutrition lead to local inflammation of the tissues surrounding and attaching the tooth to its socket, allowing bacterial penetration. Early periodontal disease is isolated to the gingiva and known as gingivitis.5,17 Alveolar bone may be destroyed as the disease progresses, leading to gingival pockets and tooth mobility.1,5,18 Food debris or plaque may become trapped within these pockets and create a localized infection known as a periodontal abscess.4,5,17 Periodontal disease is very common in pregnant women. Patients may complain of bleeding, foul odor, bad taste, loose teeth, pain, or swelling. The physical examination reveals gingival tissue that may be erythematous or necrotic and bleed easily. Heavy accretions of dental plaque and calculous may be present. An abscess may present as a focal swelling, tooth mobility, pain on percussion, and purulence that is expressible from the gingival sulcus.1,5,17,18 It may be impossible, with current dental caries, to differentiate a periapical abscess from a periodontal abscess without radiographs.3,5 In fact, both lesions may occur together.18 A periodontally diseased tooth may be so mobile that it cannot be salvaged and requires extraction.5 True periodontal abscesses rarely spread beyond the local dentoalveolar structure and rarely require an urgent referral.3,4 Treat an isolated periodontal abscess with dental anesthesia, incision and drainage, and dilute peroxide (1:5 solution or 5%) or chlorhexidine
rinses. Prescribe oral antibiotics for evidence of spread, if there is a delay to definitive care, or for systemic manifestations.1,3–5,18 Appropriate antibiotics include penicillin, clindamycin, or erythromycin. Refer patients with these lesions to a Dentist within 24 to 48 hours for definitive follow-up care to avoid recurrence.1,3,5
PERICORONITIS Inflammation can occur around the crown of any erupting tooth and is common around impacted teeth, especially the third molars.1,3,4,19 This condition is known as pericoronitis. It is often exacerbated by the impaction of food under the soft tissue. Progression of the primary process or overzealous treatment can easily lead to extension of the infection posteriorly to multiple contiguous spaces, including the retropharyngeal space.1,3,19,20 Simple cases are easily managed in the Emergency Department. Always maintain a very low threshold for consultation and referral of patients with complicated presentations. Treatment of pericoronitis may include dental anesthesia, direct saline irrigation, warm saltwater rinses, dilute peroxide or chlorhexidine rinses, and oral analgesics. The presence of swelling, trismus, and inflammation may be severe enough to warrant a course of oral antibiotics.1 Some authors advocate antibiotic coverage in essentially all cases.1,10,19,21 Definitive treatment requires the completed eruption or extraction of the tooth. Refer the patient to a Dentist or Oral Surgeon for follow-up and definitive care within 24 to 48 hours.
INDICATIONS The indications for dental abscess incision and drainage include a periapical or periodontal abscess with clinical evidence of alveolar penetration and soft tissue spread.9,10 Some authors recommend incision and drainage for purely cellulitic processes.4,5,11 Extraoral incision and drainage is indicated only for dental infections progressing toward inevitable spontaneous extraoral drainage.3,10 Drain all other dental abscesses intraorally.
CONTRAINDICATIONS A review of the current literature reveals no direct contraindications to the incision and drainage of a dental abscess. Maintain a low threshold for consultation and referral to a surgical specialist for
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TABLE 177-2 Prophylactic Regimens for Endocarditis in Patients Undergoing Dental or Oral Surgical Procedures23,* Situation Antibiotic choice Adult dose Standard general prophylaxis and able to take oral medications Amoxicillin 2000 mg PO Standard general prophylaxis and unable to take oral medications Ampicillin 2000 mg IV or IM or Cefazolin 1000 mg IV or IM or Ceftriaxone 1000 mg IV or IM 600 mg PO Penicillin allergic patient able to take oral medications Clindamycin or 2000 mg PO Cephalexin or Cefadroxil‡ or 500 mg PO Azithromycin or Clarithromycin Penicillin allergic patient unable to take oral medications Clindamycin 600 mg IV or IM or Cefazolin‡ 1000 mg IV or IM or 1000 mg IV or IM Ceftriaxone‡
Pediatric dose† 50 mg/kg PO 50 mg/kg IV or IM 50 mg/kg IV or IM 50 mg/kg IV or IM 20 mg/kg PO 50 mg/kg PO 15 mg/kg PO 20 mg/kg IV or IM 50 mg/kg IV or IM 50 mg/kg IV or IM
* Administer the antibiotics 30 to 60 minutes prior to the procedure. † The pediatric, weight-based dose should not exceed the adult dose. ‡ Do not use cephalosporins in a patient with a history of a penicillin allergy and any of the following: anaphylaxis, angioedema, respiratory difficulties, urticaria, or unknown reactions.
any patient with rapidly progressing infections, difficulty breathing, difficulty swallowing, fascial space involvement, temperature greater than 101 °F (38.3 °C), white blood cell count greater than 10,000, severe trismus (manifested by mandibular opening less than 10 mm or inability to adequately visualize the hypopharynx), a toxic appearance, compromised host defenses, or who are children.3,6,10,22
EQUIPMENT • • • • • • • • • • • • •
#15 scalpel blade on a handle #11 scalpel blade on a handle Povidine iodine or chlorhexidine solution Minnesota retractor Wieder tongue retractor Frazier suction catheter Suction source and tubing Needle driver Hemostat Suture, 4-0 and 5-0 silk Gelfoam 0.25 inch wide Penrose drain Light source, overhead or headlamp
PATIENT PREPARATION Explain the procedure, its risks, and benefits to the patient and/or their representative. Obtain dental radiographs if the infection is from a dental source.5,6,10 Obtain an informed consent for the procedure. Provide adequate anesthesia; ideally in the form of a dental block. Obtain a separate informed consent for the dental block. Direct infiltration into the area of purulence does not achieve adequate anesthesia and risks spreading the infection by inoculation.3,5 Dental blocks may require augmentation with direct infiltration anterior and posterior to the abscess. Anesthetize the areas adjacent to the abscess last to avoid seeding. Refer to Chapter 176 for a complete discussion of dental analgesia and anesthesia. The application of procedural sedation may be required if adequate
local anesthesia is not possible.10 Refer to Chapter 129 for the complete details regarding procedural sedation and analgesia. Prophylaxis to prevent infective bacterial endocarditis should be addressed in the appropriate patients prior to incision and drainage of a dental abscess in accordance with the policy put forth by the American Dental Association. Further information and specific antibiotic regimens can readily be found at the website of either the American Heart Association or the American Dental Association (Table 177-2).23,24
TECHNIQUES SIMPLE INTRAORAL INCISION AND DRAINAGE There are two techniques for intraoral incision and drainage. The first technique is to make a simple stab incision with a #11 scalpel blade in the area of greatest fluctuance and in the area that best facilitates dependent drainage (Figure 177-4A). Do not make the incision more than 1 cm in length. Gently insert a closed, curved hemostat into the incision (Figure 177-4B). Gently spread the jaws of the hemostat in several different directions to break up any loculations (Figure 177-4C). Express and suction any remaining purulence. Insert a sterile rubber drain cut from a 0.25 inch wide Penrose drain or from a sterile surgical glove (Figure 177-4D). Place one to two silk sutures through the drain and the oral soft tissues. This will ensure that the drain does not fall out and result in premature closure of the incision or aspiration of the drain. The second technique for simple intraoral incision and drainage differs only in the location of the incision. Make an incision with a #15 scalpel blade at the alveolar crest within the gingival sulcus, scalloping around the teeth. Extend the incision one tooth medial and distal to the tooth in question or the area of the abscess. Gently elevate the attached gingiva from the bone with a blunt instrument. Continue the blunt dissection until the abscess cavity is penetrated. This typically occurs just within the level of unattached gingiva. The remainder of the procedure is as described above. This technique affords some mechanical advantages to the operator and is well tolerated by the patient postoperatively. It can be performed in both arches, buccally, palatally, and lingually. It is often useful for draining a periodontal abscess.
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FIGURE 177-4. Incision and drainage of a periapical abscess that has extended into a vestibular abscess. A. Make a stab incision with a #11 scalpel blade. B. Insert a hemostat into the incision. C. Advance the hemostat into the abscess cavity to lyse any adhesions. D. Place a sterile drain into the abscess cavity.
EXTRAORAL INCISION AND DRAINAGE Extraoral incision and drainage is indicated when a dental infection appears to be progressing toward inevitable spontaneous extraoral drainage.10 This procedure requires more attention and skill because of the numerous underlying vital structures and the possible cosmetic consequences.3,10 Make every effort to avoid extraoral incision and drainage.3 Consider consulting a Dentist or Oral Surgeon before performing an extraoral incision and drainage. Extraoral incision and drainage differs from the intraoral approach.3,10,11 Advise the patient that they will almost certainly have a visible scar after the incision heals.3,10 Extraoral incision and drainage requires the use of aseptic technique. Prepare the area
with povidone iodine or chlorhexidine solution and allow it to dry. Apply sterile drapes to isolate a field. Perform local subcutaneous infiltrative anesthesia of the skin. Use a separate needle and syringe for any intraoral anesthetic techniques. Make a 1.0 to 1.5 cm long incision with a #15 scalpel blade in an area of healthy skin, proximal to the site of expected breakdown and in a location that facilitates dependent drainage (Figure 177-5). Extend the incision into the subcutaneous tissues. This is another critical difference from the intraoral technique. Insert a hemostat to penetrate and drain the abscess cavity. Spread the hemostat in several directions to break up any loculations. The remainder of the procedure is performed as described as above. Scarring with extraoral incisions is virtually universal.
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AFTERCARE The application of warm moist compresses, oral fluids, rest, and good nutrition are mainstays in the treatment of any inflammatory process. Patients may benefit from a soft, bland diet and frequent oral rinses with a warm saltwater solution. All patients require postoperative oral analgesics.3,5,10,11 Patients with an extraoral incision require dressing changes.3,5,10,11 Provide the patient with adequate supplies and teaching. Instruct the patient on the application of pressure if postprocedural bleeding occurs. The use of antibiotics in light of adequate drainage is somewhat controversial. Clear-cut indications for oral antibiotics in orofacial infections include cellulitis, extraoral incision, systemic symptoms, persistent infection, pericoronitis, fascial space involvement, and immunocompromised patients.4,7,10,16 The prudent Emergency Physician is advised to err on the side of caution while the academics quarrel over antibiotic indications. Penicillin is the drug of choice for the empiric treatment of dental-related infections. Alternatives to penicillin include erythromycin, clindamycin, or a cephalosporin. Clindamycin is the first alternate choice. It is especially useful when anaerobes are suspected or in recalcitrant infections where sensitivities are lacking.3,5,6,10 Allow the intraoral drain to remain in place until the swelling has resolved and purulent drainage has ceased. Evaluate the patient for drain removal or advancement in 24 to 48 hours. Prescribe oral antibiotics and analgesics during this time. Refer the patient to a Dentist within 24 hours.
COMPLICATIONS FIGURE 177-5. Extraoral drainage of a dental abscess. Choose a location that has healthy skin and that will allow dependent drainage.
PEDIATRIC CONSIDERATIONS Facial infections in children tend to develop and progress more rapidly. They are more likely to present with systemic signs and symptoms.25 Facial infections in children are also more likely to be associated with complications, such as dehydration or bacteremia.25 Unlike adults, the anatomic location of a facial infection in a child can be a more useful guide in determining its source and management.25 In general, upper face infections tend to be more common in children less than 5 years of age and frequently have no identifiable source. Children older than 5 years of age more commonly have lower face infections and typically have an odontogenic or woundrelated source.25 According to the American Academy of Pediatric Dentistry, a child presenting with a facial swelling secondary to a dental infection should receive immediate dental attention.26 Lastly, in sharp contrast to adults, children with facial infections in either location more frequently respond to antibiotics alone and may not require an incision and drainage procedure.25
ASSESSMENT Basic postoperative assessment includes inspecting the operative site for the minor complications described below. Assess adequate drain retention. A loose intraoral drain may represent an aspiration risk. Observe the patient for postprocedural bleeding. It can be controlled with the application of pressure, injection of a local anesthetic agent containing epinephrine, or topical Gelfoam. Wound cultures are not indicated unless the patient is immunocompromised or the infection is recurrent. The wound cultures usually demonstrate mixed oral flora with no predominate organism.
Minor postoperative pain, swelling, bleeding, drainage, and possibly bruising can be expected following the incision and drainage of a dental abscess. Significant postprocedural bleeding can be controlled with pressure, a vasoconstricting local anesthetic agent, or topical Gelfoam.5,6,17,18 An incision and drainage tract that communicates freely between the oral cavity and the external face represents a significant complication. Refer these patients to a Plastic or Oral Surgeon.
SUMMARY The recognition of common dental-related infections such as pericoronitis, periodontal abscesses, and dental abscesses can impact patient prognosis and morbidity. The diagnosis and treatment of these maladies, and their complications, requires knowledge of dental anatomy and pathophysiology. The Emergency Department management of these infections is quick and simple. Refer all patients to a Dentist or Oral Surgeon for definitive care of their teeth.
178
Post-Extraction Pain and Dry Socket (Alveolar Osteitis) Management Eric F. Reichman
INTRODUCTION Post-extraction pain, or periosteitis, begins as the local anesthetic agent wears off. The pain begins to diminish, most of the time, within 12 hours. The prescription of nonsteroidal antiinflammatory drugs will provide analgesia and comfort while the
CHAPTER 178: Post-Extraction Pain and Dry Socket (Alveolar Osteitis) Management
pain subsides over 1 to 2 days. Narcotic analgesics may occasionally be required for the first 24 to 48 hours. Pain that develops 2 to 4 days after the tooth extraction most likely indicates a localized alveolar osteitis or a dry socket. A dry socket occurs most commonly with the extraction of the third mandibular molar, but can be associated with any tooth that has been extracted. The pain is quite severe in nature and is localized to the area of the extraction site. The extraction site may emit a foul odor and the patient often complains of a bad taste in their mouth.1,2 Physical examination may reveal the socket is missing a clot, but this is sometimes difficult to identify. The signs of an infection are absent.
ANATOMY AND PATHOPHYSIOLOGY The exact etiology or the pathogenesis of a dry socket is not clear.1–6 It may be multifactorial due to smoking, a localized infection, a poor blood supply, traumatic extractions, a foreign body in the socket, and certain medications. These factors result in an increased level of fibrinolysis of the blood clot in the socket before the clot has had the time to be replaced by granulation tissue. The clot falls out of the socket and exposes the bony surface of the socket to the oral cavity. The exposed bone is extremely sensitive to air, resulting in severe pain.1–4
INDICATIONS The single and utmost therapeutic goal of alveolar osteitis is to relieve the patient’s pain during the healing process. This procedure should be performed on all patients with a dry socket.
CONTRAINDICATIONS
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performed and the anesthesia wears off while the patient is still in the Emergency Department. Refer to Chapter 176 for the complete details regarding dental anesthesia and analgesia. Consider obtaining a plain radiograph or panorex to rule out a retained root tip or foreign material in the socket.
TECHNIQUES Identify the defective tooth. Gently and thoroughly irrigate the socket with warm normal saline and low-level suction to remove any debris. Use a forceps to pack dry socket paste into the socket. Dry socket paste is composed of balsa wood fragments saturated with eucalyptol and looks like chewing tobacco. Completely fill the socket with the dry socket paste. The patient will experience almost instant pain relief if a dental block was not performed. Place a piece of Gelfoam on top of the dry socket paste. Compress the Gelfoam and dry socket paste into the socket. Instruct the patient to bite down against a 2 × 2 gauze square placed over the socket for 5 to 10 minutes. Dressol-X may be used instead of dry socket paste if available. Unfortunately, few Emergency Departments stock dry socket paste or Dressol-X. An alternative is ribbon gauze or Gelfoam impregnated with eugenol, iodine, or oil of cloves. Ribbon gauze tends to dry out and fall out sooner than commercially available dry socket paste. Use a forceps to pack the socket completely with the impregnated ribbon gauze (Figures 178-1A to C) or Gelfoam. Place a piece of plain Gelfoam on top of the socket (Figure 178-1D). Compress the plain Gelfoam and the underlying impregnated ribbon gauze or impregnated Gelfoam into the socket. Instruct the patient to bite down against a 2 × 2 gauze square placed over the socket for 5 to 10 minutes.
There are no contraindications to the management of a dry socket.
ASSESSMENT
EQUIPMENT
The patient should experience almost immediate pain relief after the socket is packed. If a dental block was performed, allow the local anesthetic to wear off to ensure the patient’s pain truly has resolved.
• • • • • • • • • • • • •
Dental mirror 2 × 2 gauze squares Scissors Dry socket paste or Dressol-X Gelfoam Irrigating syringe Normal saline solution Frazier suction catheter Suction source and tubing Forceps Iodoform ribbon gauze Eugenol-impregnated ribbon gauze Oil of cloves
PATIENT PREPARATION Explain the risks, benefits, potential complications, and aftercare to the patient and/or their representative. A signed consent is not required for this procedure. Place the patient sitting upright or reclining. A multipositional dental chair is ideal and allows for a variety of positions to visualize the affected tooth. This procedure may be accomplished with no anesthesia. Some may consider performing a dental block to temporarily alleviate the patient’s pain and allow the procedure to be accomplished with minimal discomfort, and increase the level of patient satisfaction. If performed, use lidocaine without epinephrine because the procedure is quickly
AFTERCARE The patient may be discharged immediately after the procedure, or after the local anesthetic has worn off. Nonsteroidal antiinflammatory drugs are usually adequate to provide analgesia. Narcotic analgesics are not needed nor required. Arrange follow-up as soon as possible with the Dentist or Oral Surgeon who performed the extraction procedure. The dressing must be replaced daily, or as needed, until the patient is pain free. Instruct the patient to begin a soft diet, to not ingest extremely hot or cold substances, and to not play with the packing with their tongue. Instruct the patient to also not suck anything, use a straw, gargle, spit, or smoke. All these activities will produce negative pressure within the oral cavity and remove the clot from the extraction site. The decision to prescribe antibiotics to cover the oral flora is physician dependent. There is no literature to support or refute this practice. Consult the Dentist or Oral surgeon who extracted the tooth. Oral penicillin VK (500 mg QID) is the preferred antibiotic if they are prescribed. Clindamycin (300 mg QID) is an alternative for patients allergic or intolerant to penicillin.
COMPLICATIONS There are no complications associated with this procedure. A potential complication is the aspiration of the material used to pack the socket. This has never been reported in the literature. The packing may fall out and result in the patient’s pain recurring. Instruct the
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FIGURE 178-1. Packing a dry socket with ribbon gauze. A. The empty socket. B. Pack the socket starting inferiorly and working upward. C. Completely fill the socket. D. Apply Gelfoam over the socket and the ribbon gauze.
patient to return to the Emergency Department if the packing falls out prior to their follow-up appointment.
SUMMARY A dry socket can be extremely painful. Packing an empty socket is easy, quick, simple, and provides the patient with significant relief. The packing needs to be changed daily for several days and then less frequently after that, until the patient is free of pain. Prescribe antibiotics to cover oral flora and analgesics to manage pain.
179
Post-Extraction Bleeding Management
pressure within the oral cavity and remove the clot from the extraction site. Ask the patient if they are touching the extraction site with their tongue, causing a mechanical disruption of the clot. Obtain information about any significant medical history, any history of bleeding, and current medications. This includes use of aspirin products, anticoagulants, broad-spectrum antibiotics, alcohol, and antineoplastic medications. These all may contribute to prolonged bleeding. Ask about the symptoms and examine for the signs of liver disease, hypertension, or hematologic disorders.1,2 Postextraction bleeding may be a sign of an underlying and undiagnosed coagulopathy.
INDICATIONS All post-extraction bleeding must be managed carefully and methodically. The techniques are easy to perform, simple, and straightforward.
Eric F. Reichman
INTRODUCTION Post-extraction bleeding is a common problem after the removal or extraction of a tooth. It is often seen in the Emergency Department in the late evening or night when the patient is unable to contact their Dentist. Bleeding that occurs within a few hours of the extraction is often due to the wearing off of the vasoconstrictor effect of the local anesthetic solution used for anesthesia. The application of direct pressure over the bleeding site by having the patient bite down on a folded piece of moist gauze almost always controls postextraction bleeding. Many patients, however, will report that they have been doing this prior to coming to the Emergency Department and require additional assistance.
ANATOMY AND PATHOPHYSIOLOGY A careful history may reveal that the patient inadvertently caused the extraction site to bleed by drinking through a straw, spitting, gargling, or smoking. All these activities will produce negative
CONTRAINDICATIONS There are no contraindications to the management of postextraction bleeding.
EQUIPMENT • • • • • • • • • •
2 × 2 gauze squares Irrigating syringe Dental mirror, optional Local anesthetic solution containing 1:100,000 epinephrine 23 to 25 gauge, 1.5 inch needle 5 mL syringe Silk or plain gut sutures, 4-0 or 5-0 Absorbable gelatin sponge (Gelfoam) Oxidized regenerated cellulose (Surgicel) Topical thrombin
CHAPTER 179: Post-Extraction Bleeding Management
• • • • • • • • • •
Suture set Dental forceps Tea bag Bone rongeur Bone wax Headlamp Yankauer suction catheter Suction source and tubing Silver nitrate matchsticks Electrocautery unit
PATIENT PREPARATION Explain the risks, benefits, potential complications, and aftercare to the patient and/or their representative. Document this discussion in the medical record. A signed consent form is usually not required for these procedures. Consider obtaining a radiograph of the affected area to rule out a retained root or a bony spur. Position the patient to visualize the extraction site. Place the patient in a multipositional dental chair, if available, or on a gurney. Do not place the patient in a chair as they may become presyncopal and require being placed supine to prevent injury. An overhead light source or a headlamp is ideal to illuminate the field. Suction any blood and oral secretions from the mouth. Visualize the extraction site for any signs of bleeding. Thoroughly irrigate the site with warm saline and remove all clots with the aid of suction. It may be necessary to perform a dental block if the patient complains of pain upon irrigation. Refer to Chapter 176 for the complete details regarding dental anesthesia and analgesia.
TECHNIQUES The management of post-extraction bleeding is simple. Numerous methods to control the bleeding have been described and tested (Table 179-1). These techniques are often performed in a sequential manner as described below. The techniques may, of course, be performed in any order, depending on the physical examination and physician preference.
MECHANICAL PRESSURE Place saline-moistened 2 × 2 gauze squares over the socket. Instruct the patient to apply firm pressure by biting down on the gauze for 20 minutes. Instruct the patient to maintain pressure for 20 minutes despite initial bleeding. Place the suction catheter, intermittently, into the vestibule of the mouth to remove any blood and secretions. The application of pressure will control most postextraction bleeding. It may be necessary to perform a dental block, if not performed during the irrigation phase, if the patient cannot bite down due to pain.
TABLE 179-1 Methods to Control Post-Extraction Bleeding Absorbable dressing into socket and mechanical pressure with gauze squares Absorbable dressing into socket and stitch gingival tissue closed Cauterize bleeding granulation tissue Cauterize or stitch bleeding blood vessels Gingival infiltration with local anesthetic containing epinephrine Mechanical pressure with gauze squares Moist tea bag and pressure Rongeur or apply bone wax to bone spurs Stitch gingival tears
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TEA BAG APPLICATION Place a saline-moistened tea bag in the socket if mechanical pressure does not control the bleeding. The tannins in the tea leaves will assist with the coagulation process. Instruct the patient to bite down on the tea bag for 15 minutes.
ABSORBABLE DRESSINGS The two most commonly used absorbable dressings are Gelfoam and Surgicel. Gelfoam is an absorbable gelatin sponge that is readily available and inexpensive. It forms a scaffold for the formation of a blood clot. Surgicel is composed of oxidized and regenerated cellulose. It promotes coagulation better than Gelfoam and can be packed into the socket under pressure. Unfortunately, Surgicel results in delayed healing of the socket and its use should be reserved for persistent bleeding or when Gelfoam is not available. Place an absorbable dressing (Gelfoam or Surgicel) in the socket if the extraction site continues to bleed.1–3 The author prefers to use Gelfoam because it is easier to manipulate and it is absorbed more rapidly than Surgicel. Work the Gelfoam in your fingers until it resembles the shape of the socket. Insert the Gelfoam into the socket and compact it with a dental forceps. Insert additional pieces of Gelfoam into the socket, as necessary, to obtain a solid mass of Gelfoam filling the socket. An alternative is to pack the socket with Surgicel. Once the socket is packed, apply a 2 × 2 gauze square over the socket. Instruct the patient to bite down for approximately 20 to 30 minutes. The author prefers to place a figure-ofeight stitch using 4-0 or 5-0 silk suture or plain gut suture over the socket (Figure 179-1). The suture applies pressure over the socket and ensures that the Gelfoam or Surgicel will not prematurely fall out of the socket. This technique will usually stop most postextraction bleeding. Two additional absorbable dressings are topical thrombin and collagen. They are expensive, not usually available in the Emergency Department, and their use should be limited to circumstances where other hemostasis methods have failed. Topical thrombin is made from bovine thrombin. Place a piece of Gelfoam or Surgicel saturated with thrombin into the socket. Thrombin converts fibrinogen to fibrin, bypassing the coagulation cascade, to form a clot within the socket. Collagen is available in multiple forms from a variety of sources. It promotes platelet aggregation and forms a scaffold for the formation of a clot. Pack the socket with collagen and cover it with a piece of Gelfoam. Place a figure-of-eight suture over the thrombin or collagen-filled socket to secure it in place. The use of chitosan bandages to control battlefield and prehospital hemorrhage has crossed over into the dental realm. Chitosan dental bandages (HemCon Medical Technologies, Portland, OR) have
FIGURE 179-1. Pack the socket with Gelfoam followed by a figure-of-eight stitch to control the bleeding.
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been designed to control post-extraction hemorrhage. Chitosan is a naturally occurring polysaccharide derived from shellfish. It attracts red blood cells. When placed over the bleeding extraction site, the red blood cells attach to the bandage to form a clot and tamponade the bleeding.
LOCAL ANESTHETIC INFILTRATION Infiltrate the soft tissue surrounding the socket with local anesthetic solution containing epinephrine if the bleeding is not controlled by the above methods. The most commonly used local anesthetic solutions are lidocaine and bupivacaine. Infiltrate the soft tissues surrounding the socket with the local anesthetic solution until the tissue blanches. This usually requires 2 to 3 mL of the local anesthetic solution. Irrigate the socket. Apply a piece of moist gauze over the socket. Instruct the patient to bite down and to exert pressure on the socket. The patient is often able to bite down much harder on the tissues after the infiltration of the local anesthetic solution. The effect of mechanical pressure combined with the vasoconstrictive effects of epinephrine control the bleeding. Occasionally, after the vasoconstrictive effect of epinephrine wears off, there is a rebound effect and the persistence of bleeding. This may be prevented by routinely placing Gelfoam or Surgicel into the socket after the bleeding is controlled.
MISCELLANEOUS TECHNIQUES Reexamine the extraction site if the bleeding is not controlled by the above methods. The source of bleeding may be new granulation tissue, gingival tears, a bone spur, or a partially transected vessel. Cauterization of granulation tissue with silver nitrate or electrocautery will control the bleeding. Handheld, disposable, single-patient use electrocautery units work well but require the patient to be anesthetized. Use a blunt instrument to feel for the presence of a bone spur. This may be a source of significant bleeding. Remove the bone spur with a rongeur or cover it with bone wax to control the bleeding. An exposed and bleeding arteriole or venule can be controlled with cauterization (silver nitrate or electrocautery) or the application of a plain gut suture through the vessel. Suture any tears in the gingiva.
ASSESSMENT Observe the patient for 30 to 60 minutes after the bleeding has terminated. Do not give the patient anything by mouth (NPO). Reevaluate the socket for signs of bleeding. Continued bleeding requires further attempts at termination.
AFTERCARE Discharge the patient home after the bleeding has been terminated and a brief observation period. Instruct the patient to avoid any liquids or solids for 2 hours. Stress the importance of not spitting, gargling, drinking through a straw, smoking, using aspirincontaining products, or playing with the site with their tongue. Instruct the patient to apply gauze squares and bite down for 20 minutes if the bleeding returns. They should return promptly to the Emergency Department if the bleeding continues after 20 minutes. Additional instructions should include a soft diet, avoidance of extremely hot or cold substances, avoidance of chewing gum, and avoidance of other such “sticky” foods. Arrange follow-up as soon as possible with the Dentist or Oral Surgeon who performed the extraction.
COMPLICATIONS There are no documented complications associated with the termination of post-extraction bleeding. The complications are associated with the bleeding itself. Obtain screening labs (e.g., PT, PTT, platelet count, and bleeding times) if hemostasis is not achieved by any of the aforementioned methods. Early consultation with a Dentist or Oral Surgeon and a Hematologist should be considered if the patient is coagulopathic or has a bleeding disorder.
SUMMARY A careful history and physical examination will often provide the reasons for most post-extraction bleeding that presents to the Emergency Department. Most patients without complicating medical conditions will be easily managed in a simple and systematic manner with a minimal amount of equipment. All patients should follow-up with their Dentist or Oral Surgeon after the bleeding is terminated.
180
Defective Dental Restoration Management Daniel J. Ross
INTRODUCTION The field of restorative dentistry is a complex specialty that derives from many disciplines. Patients have often invested considerable time, money, and quite possibly “blood, sweat, and tears” in their dental work. This may be particularly true with the advent of both cosmetic and implant dentistry, which involve long and complicated treatment plans that are often not covered by insurance. A patient’s investment in their dental work and the technical complexity of today’s dental appliances should not be taken lightly. In fact, the treatment of common dental emergencies was published in the Emergency Medicine Clinics of North America under the heading “Difficult and Advanced Procedures”.1 The urgent management of an acutely problematic dental restoration can be as simple as relieving discomfort, treating injury and infection, and employing temporizing measures until definitive treatment can be rendered by the appropriate specialist. This requires a basic understanding of dental anatomy, the pathophysiology of various dental states, and their typical treatment modalities.1,2 It goes without saying that one should also recognize the inherent and all too frequent limitation of treating these problems in the Emergency Department. The key to the successful emergent or urgent management of an acutely problematic defective dental restoration is stabilization and timely referral with great care to “first, do no harm”. A few basic principles serve as a useful guide in treating patients with defective dental restorations. First, know your limitations. Dental pain in general, and a defective dental restoration in particular, is rarely if ever, a true emergency.2–4 Chronic problems should be treated with equal measures of conservatism and reluctance. Refer the patient to a Dentist if you are hesitant to treat or are unfamiliar with an appliance or a presentation. Always consider a secondary or comorbid process. Consider the utility of dental radiographs when in doubt. Never remove a fixed appliance without first discussing it with a specialist, preferably the one who placed it. Save anything
CHAPTER 180: Defective Dental Restoration Management
and everything that belongs to the patient, whether it be appliance or tissue, as it may have utility for the definitive treatment.5,6 Treat pain, inflammation, and evidence of infection. Consider a reversible or temporary solution over all others. Remember to treat a tooth for dental trauma if a restoration is determined to be defective secondary to trauma. Always consider ingestion or aspiration when dealing with a multiply fragmented tooth or appliance. Consider facial, neck, chest, and abdominal radiographs if all fragments cannot be accounted for.5,7–10 Whenever a patient is actively involved in an ongoing treatment process, it is probably best to do as little as possible. Always use caution and tact when discussing the possibility of a defective dental restoration with a patient. Remember that you are not an expert. The treating specialist may have insight into the patient’s current condition that you are unaware of. Attempt to consult before treating. Always arrange follow-up within 24 to 48 hours.
ANATOMY AND PATHOPHYSIOLOGY Patients frequently present to the Emergency Department with some sort of dental complaint and their primary concern is typically pain related.1,2,11,12 The perioral tissues are exceptionally sensitive to noxious stimuli. This is particularly true for the oral mucosa, periodontal ligament, dentin, and pulp. This concept is paramount to the effective management of any dental-related complaint. Although a patient’s chief complaint may be directed at a particular tooth, be diligent in searching the entire mouth for alternative primary, comorbid, or secondary problems. A meaningful discussion of the management of defective dental restorations requires a brief outline of the available types of dental appliances. In general, dental appliances are either fixed or removable. Fixed dental appliances are considered permanently attached to the teeth. They include crowns, bridges, implants, some forms of dentures, orthodontic bands and brackets, interdental wiring, and any type of filling (e.g., silver amalgam, gold, porcelain, or toothcolored composite material). Removable dental appliances are those that are not permanently attached to the teeth and include partial dentures, complete dentures, space-maintenance devices, and other orthodontic devices. Understanding whether a defective dental device is permanent or removable is often the first step in managing an acutely problematic appliance. Removing a broken or defective removable appliance is a simple and easy solution if it can be done safely and without
FIGURE 180-1. Commercially available home repair kits for the fractured denture.
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significantly damaging the appliance. If removal would significantly alter or damage an appliance and there is no other reasonable option but to remove it, document the discussion with the patient and their consent to proceed. This is true whether the appliance is permanent or removable. Removable dental appliances can predispose patients to several easily treatable mucosal conditions such as ulcerations, abrasions, or mucosal infections.13,15 Compromised cellular immunity, broad-spectrum antibiotics, low salivary flow, poor oral hygiene, and trauma from poorly fitting dentures can all contribute to oral candidal overgrowth.13,16 Patients often complain of burning pain. Treat the oral cavity with nystatin or clotrimazole troches. The appliance itself may harbor the organism and must be treated. Instruct the patient to take the appliance out of their mouth for 24 to 48 hours and soak it overnight in a nystatin suspension [5 mL nystatin in 250 mL (8 ounces) of tap water]. Instruct the patient to scrub the denture daily with an approved product to clean it.13–15 Oral candidiasis must be differentiated from other mucosal ulcerating conditions such as simple traumatic ulcers, aphthous ulcers, and oral herpes. Herpetic lesions occur on attached mucosa only, whereas aphthous ulcers occur on unattached mucosa.13–16 Traumatic ulcers, minor aphthae, and major aphthae can be treated with topical corticosteroid ointment, such as triamcinolone, applied with a cotton-tipped applicator. The symptoms associated with herpetic outbreaks can be diminished if treated with acyclovir or a similar antiviral agent.13–15 Orthodontic or interdental wiring that is impinging upon the oral mucosa may lead to traumatic ulcerations. Apply soft dental wax directly to the irritating appliance to relieve the impingement. This can be easily removed or replaced and is available over the counter at many local pharmacies. In general, all patients with painful mucosal conditions may benefit from soft and bland diets, frequent use of ice chips for discomfort, and frequent warm saltwater rinses to avoid superinfection.13,14 A stomatitis cocktail or BMX solution may be helpful for patients with severe mucosal pain. Mix equal amounts of Benadryl (12.5 mg/5 mL), Maalox, and Xylocaine (2% viscous lidocaine). Instruct the patient to swish 30 mL in their mouth for 1 minute and then spit it out. The repair of broken or defective removable appliances in the Emergency Department is not recommended even though multiple over-the-counter products are available for home use (Figure 180-1).16 Under the best of circumstances these procedures
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SECTION 14: Dental Procedures
can be tedious, time consuming, and fraught with complications— even for the trained dental professional.3 Most importantly, a botched repair attempt can result in patient discomfort, morbidity, and irreversible damage to an otherwise salvageable appliance. In this light, it seems best to simply recommend removal and a dental referral to the patient seeking care for a broken removable appliance.16 Although far less than ideal, a home repair kit may be a viable option for some patients under certain circumstances. The temporary urgent repair of defective fixed dental restorations by nondental personnel is advocated throughout the literature.2,3,11,12,14,17–19 Use caution, however, when evaluating a new or recently placed fixed restoration because sensitivity from recent dental procedures can occur due to pulpal or periodontal ligament (PDL) irritation.20 This may be a normal and expected sequelae of the dental procedure and not necessarily an indication that the restoration is defective.1,20,21 Trauma from occlusion can result if a new dental restoration is left “too high” and does not fit properly with the opposing dentition.3,14,18–20 These patients complain of pain with mastication and are sensitive to percussion secondary to PDL irritation. Do not alter a fixed restoration if it is firmly in place. Simple temporizing measures include dental blocks (Chapter 176), oral analgesics, a soft diet, and possibly removing the tooth from occlusion by placing a small amount of soft dental wax (or something similar) between the teeth on the opposite side.3 Long-standing fixed dental restorations may be defective secondary to microleakage or recurrent decay around the margins of the restoration.1,20 Estimates suggest that approximately one in three restorations in existence may be defective in some fashion.20,21 A faulty restoration that sits within or upon a tooth can lead to dentinal exposure regardless of the etiology. Exposed dentin is highly sensitive and prone to further decay. Dentinal sensitivity (also known as reversible pulpitis) is typically nonspontaneous and fleeting.1,16,18,22 Patients who complain of spontaneous and lasting sensitivity have an irreversible pulpitis that is most likely due to recurrent decay. Sensitivity to percussion is indicative of periapical involvement and suggests the possibility of a periapical periodontitis or an abscess.1,14,16,18,22 Evaluate the tooth and its restoration for recurrent decay or a possible dentinal exposure if a patient present complaining of sensitivity associated with a tooth that has a long-standing restoration. A temporary restoration can easily be fabricated in the Emergency Department if the restoration in question is missing, broken, or easily removed. Consideration should be given to a possible pulpal pathology, as outlined above, if a restoration is firmly in place. Provide dental anesthesia, oral analgesics, antibiotics as necessary, and a referral to a Dentist. Refer to Chapter 177 for the details regarding the management of dental abscesses.
INDICATIONS Replace any previously fixed, permanent or temporary, dental restoration that has completely or partially fallen out or that is easily removed with a dental explorer. Replace any previously fixed, permanent or temporary, crown that has fallen out or is easily removed with a dental explorer and is in the patient’s possession.
CONTRAINDICATIONS Relative contraindications for the placement of a temporary dental filling, or temporarily recementing a crown, include patients who are involved with an extensive ongoing dental treatment plan, have a consulting specialist readily available, are at a significant aspiration risk, or have obvious extensive comorbid or secondary processes including antecedent trauma.
EQUIPMENT • • • • • • • • • • • • • • • • • • • • • •
10 mL syringe 18 gauge angiocatheter Normal saline solution Local anesthetic solution containing epinephrine Dental mirror Dental explorer 2 × 2 gauze squares Sterile cotton rolls Dental floss Clear nail polish Cavit-G IRM (zinc oxide and eugenol) Dycal (calcium hydroxide paste) Copalite (cavity varnish) or clear acrylic nail polish Tin foil Cotton-tipped applicators Discoid-cleoid dental carver Articulating paper Frazier suction catheters Suction source and tubing Petrolatum-based lubricant (Vaseline) Good overhead lighting or a headlamp
PATIENT PREPARATION Explain the procedure, its risks, complications, and aftercare to the patient and/or their representative. Obtain an informed consent for the procedure. The simple placement of a temporary filling does not usually require local anesthesia. However, consider the use of a dental block if the patient is uncomfortable. Refer to Chapter 176 for the complete details regarding dental anesthesia and analgesia. Prepare the patient. Seat the patient in a multipositional procedure chair. Gently irrigate the area with a syringe that contains warm normal saline and is armed with an 18 gauge angiocatheter to remove any food debris. Warm saline is usually less sensitive to the exposed dentin.1 Gently remove any debris that does not irrigate away with a dental explorer. Do not attempt to remove any decay because doing so may lead to a complicating pulpal exposure.1 Remove the loose portion of the restoration. Do not remove any firmly fixed portion of the restoration. It is mandatory to have a dry field when performing this procedure. Dry the area to be filled with sterile cotton pellets or compressed air. Remember that the tooth may be sensitive.
TECHNIQUES REPLACING A TEMPORARY OR PERMANENT FILLING Treatment of defective fillings depends upon the relative size of the defect. There are no specific guidelines of what size (i.e., how many millimeters) the defect must be to perform each of these techniques. Paint small dentinal exposures with calcium hydroxide paste followed by cavity varnish or clear acrylic nail polish to relieve sensitivity.1,10,14,19 Alternatively, place a simple tin foil dressing over the tooth to act as a bandage following placement of the calcium hydroxide paste.10,14,19
CHAPTER 180: Defective Dental Restoration Management
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FIGURE 180-2. Commercially available home use products for temporary dental filling and crown restoration.
Larger defects require a filling to avoid food impaction and other sequelae. Cavit-G is an excellent choice for temporary filling material, especially in inexperienced hands.1,10,12,23 This material is premixed, nonirritating, and sets quickly (approximately 30 minutes) upon contact with saliva. IRM, or a mixture of zinc oxide and eugenol, is similar material with the benefit of pulpal sedative properties. The use of IRM is operator dependent and requires a longer setting time.23 Oddly enough, multiple mixtures of zinc oxide and eugenol are available over-the-counter for home use (Dentemp, Tempanol, Thin Set; Figure 180-2). Cavit-G is recommended for Emergency Department use. Determine whether the missing filling exposes an open endodontically treated root (i.e., root canal). Place a small sterile cotton pellet into the canal prior to placing the filling material if the pulp cavity is exposed.23 Express a small amount of Cavit-G from the container. Apply it onto the cavity and condense it into the cavity with the moistened end of a cotton-tipped applicator or a dental explorer (Figure 180-3A). A temporary restoration placed by nondental personnel is always better “short” and out of occlusion with the opposing tooth for patient comfort. Work quickly because Cavit-G can set rapidly and it may be difficult to remove once it
FIGURE 180-3. Application of temporary restorative material. A. Pack the material into the defect and condense it with a dental explorer (or a cotton-tipped applicator). B. Remove any excess material.
sets. Remove any excess Cavit-G with the stick end of the cottontipped applicator. Instruct the patient to fully occlude on the new restoration and grind their teeth back and forth in all directions for 5 to 10 minutes. This will form the occlusal aspect of the filling to fit the opposing teeth if it is not made “short”. Remove any excess material with the stick end of the cottontipped applicator. Use the discoid-cleoid dental carver to remove excess material once it begins to harden (Figure 180-3B). Use dental floss to contour a proper embrasure and clear excess material from the gingival tissues. Use the dental floss in a downward direction only. Never bring the dental floss back up toward the occlusal surface because doing so risks dislodging the new restoration. Simply pull the dental floss through after one downward pass around the tooth.
REPLACING A TEMPORARY OR PERMANENT CROWN The patient preparation required for this procedure is essentially the same as that for replacing a temporary filling. However, avoid dental anesthesia if possible to allow better patient proprioception. This will provide the Emergency Physician with a crucial aid in assessing the orientation and occlusion of the final restoration.1 The same over-the-counter mixtures for repairing a filling may be used to temporarily replace a crown (Figure 180-2). Reapply the crown to ensure that it fits properly. It is often necessary to remove a small amount of the existing cement from within the patient’s existing restoration in order to provide an adequate seal and a proper occlusion.1 This may or may not be possible to do with the discoid-cleoid dental carver. Do not use rotary instruments as these may irreversibly damage the inside of the coping. Reinsert the patient’s crown after removing some of the cement to assure a proper fit and proper occlusion. Make an attempt using the alternative technique described below if sufficient preexisting cement cannot be removed and the crown seats properly. Treat dentinal sensitivity as outlined above (i.e., as replacing a filling) if the appliance does not seat at all. Proceed with this technique if the restoration appears to fit and a small amount of the preexisting cement can be removed from the inside. Prepare the area. Apply a thin layer of petrolatum-based lubricant (i.e., Vaseline) to the mucosal tissues surrounding the tooth to aid in the cleanup. Do not contaminate the prepared tooth with the lubricant.
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Prepare or mix a thin consistency of zinc oxide and eugenol cement. Place a very small amount of the mixture into the preexisting crown with a cotton-tipped applicator.3,14,18 Place the crown on the tooth and in the proper orientation. Firmly and fully seat the crown with firm finger pressure. Remove any excess cement material from around the margin of the newly cemented restoration. This may be easier once the material has hardened. Instruct the patient to gently and fully occlude on the restoration. Ensure proper occlusion. Ask the patient to provide a subjective report if their occlusion feels like baseline (i.e., does their bite feel funny). Confirm this using articulating paper to ensure that the contact marks are light or minimal. Wipe the petrolatum-based lubricant from the mucosal tissues. A simpler, alternative, and far more temporary method of replacing a crown involves using Vaseline as the cementing agent.1 Apply a thin layer of Vaseline to the inside of the coping. It may be necessary to remove a small amount of the preexisting cement. Seat the crown on the tooth in the proper orientation. Ensure proper occlusion. Warn the patient that the crown may come off again and about the risk of aspiration. Instructions may be given to the patient for repeating the procedure at home.
ASSESSMENT Check the patient’s occlusion. It may be necessary to use articulating paper to ensure minimal or no contact with the opposing teeth with the temporary filling. The newly cemented crown restoration must primarily be assessed for proper occlusion. The patient’s subjective opinion is invaluable in this regard.
AFTERCARE Instruct the patient not to eat or chew on their new restoration for at least 1 hour. Additional instructions should include a soft diet, avoidance of extremely hot or cold substances, avoidance of chewing gum, and avoidance of other such “sticky” foodstuffs. They may brush their teeth normally, but should not floss adjacent to the new restoration. Warn them that they may experience some continued sensitivity. Nonsteroidal anti-inflammatory drugs will provide any needed analgesia. Arrange follow-up within 24 to 48 hours.
COMPLICATIONS Typical complications of replacing a filling include improper occlusion and poor retention of the restoration. The solution for both problems is replacing the restoration. Adjust the occlusion with the discoid-cleoid dental carver. Treat the restoration as a dental restoration that is “too high” if using the discoid-cleoid dental carver is not effective. Treat the tooth as a simple dentinal exposure if a temporary restoration is continually falling out. An unlikely complication would be a pulpal exposure, manifested as minimal bleeding from within the tooth defect.1,10,12 Manage this as a dental trauma or fractured tooth. Typical complications for replacing a crown are similar to those listed in replacing a temporary filling. These restorations are often easily removed with a slight twisting motion. A restoration that is seated “too high” should be replaced. Treat the tooth as a simple dentinal exposure if a restoration is consistently “too high”.
SUMMARY Management of the patient with a dental complaint may initially seem intimidating to the Emergency Physician. The recognition and treatment of dental pain, minor defective dental restorations,
and painful mucosal conditions can be relatively simple provided a minimal understanding of basic dentistry. Emergency Physicians must be cognizant of the inherent limitations involved in treating these patients in the Emergency Department. Have a low threshold for referral. Pain, inflammation, and infection should always be treated. Refer patients to the appropriate specialist within 24 to 48 hours.
181
Subluxed and Avulsed Tooth Management Daniel J. Ross
INTRODUCTION Traumatic dental injuries are a common presentation to the Emergency Department. They can have significant lasting cosmetic, functional, and psychological consequences for the patient. Recent estimates indicate over three quarters of a million annual Emergency Department visits in the United States for dentalrelated complaints.1 Nearly 12% of these are related to some form of trauma.1 Approximately 50% of children will sustain traumatic dental injuries, the majority of these to the permanent dentition.2–4 Violence of a suspicious nature, such as domestic or child abuse, must always be considered when evaluating dental injuries. The appropriate Emergency Department management of dental trauma depends heavily upon the type of tooth (permanent vs. primary), the age of the tooth, the time elapsed since the incident, and the extent of the damage. Successful treatment of dental injuries requires a basic understanding of dental anatomy, terminology, and pathophysiology. The goals of the emergent treatment of dental trauma are to maintain patient comfort and tooth vitality, while ensuring prompt dental follow-up for definitive care.
ANATOMY AND PATHOPHYSIOLOGY TOOTH ANATOMY There are significant differences in the adult and pediatric dentitions that impact their treatment in the Emergency Department (Figure 181-1). The pediatric dentition is known as the primary or deciduous dentition and consists of 20 teeth. These include eight incisors, four canines, and eight molars. The adult dentition consists of 32 teeth and is composed of 8 incisors, 4 canines, 8 premolars, and 12 molars. The variable absence of a tooth or the addition of an extra tooth is common in either dentition. The teeth in both the pediatric and adult dentitions erupt in a predictable sequence, albeit with considerable individual variation (Figure 181-1). Treatment strategies differ for permanent versus deciduous (primary) teeth as well as by the age of the adult tooth. Exercise great care when evaluating patients with a “mixed” dentition, roughly between the ages of 6 and 12 years. The anatomy of a tooth is rather simple (Figure 181-2). The tooth itself consists of a neurovascular pulp surrounded by supportive dentin, which is surrounded by a hard thick crown of enamel. The crown portion lies above the gum line or gingiva. The root portion lies embedded within the alveolar bone of the jaw, anchored by a thin layer of cementum, and the periodontal ligament. The alveolar bone, periodontal ligament fibers, and fragile cementum cell layer taken together are considered a functional unit known as the attachment apparatus. A complete attachment apparatus requires
CHAPTER 181: Subluxed and Avulsed Tooth Management Primary dentition Age of primary tooth eruption (months)
Adult (permanent) dentition Age of permanent tooth eruption (years) Maxillary teeth
7–8 8–9
12–18
11–12
9–11
10–11
16–22
10–12
13–19
6–7 25–33 12–13
11–13 23–31 6–7 14–18 17–23 10–16
11–12 10–12
6–10 6–7
9–10 7–8
Mandibular teeth
FIGURE 181-1. The normal eruptive patterns of the pediatric and adult dentition.
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an intact cementum cellular layer and a fully formed root apex. Immature adult teeth do not have a fully formed apex and necessitate special attention to maintain pulpal viability.3,5–9
TOOTH INJURY Mechanisms of tooth injury include direct trauma (i.e., a blow) or occlusive trauma (i.e., biting on a hard object or a seizure). These mechanisms can result in a spectrum of injury patterns that vary from simple sensitivity to complete tooth avulsion. Crown and root fractures are discussed in Chapter 182. This chapter focuses on the diagnosis and management of dental subluxations and avulsions. Appropriate treatment of dental injuries requires a thorough history and meticulous examination of the oral cavity, including subsequent radiographs after ruling out more serious injuries. Historically, important points include the age of the patient, the time of the trauma, the mechanism of injury, the location of teeth or tooth fragments, subjective disturbance of bite, and treatments provided since the time of the incident. The physical examination must include an assessment of the extraoral and intraoral soft tissues, bony displacement, missing teeth, crown fractures, pulp exposures, tooth sensitivity, and tooth mobility. The need for radiographs with dental trauma is worth emphasizing. A tooth that is missing, both by history and physical examination, may be found completely intruded below the gum line, embedded in the perioral soft tissues, floating within the maxillary sinus or stomach, or even aspirated.10–14 Obtain facial films if a tooth, or a portion of the tooth, cannot be unequivocally located by history or physical examination. Strongly consider obtaining chest and abdominal radiographs if the tooth, or the portion in question, is not visualized on the facial films.
CONCUSSED AND SUBLUXED TEETH Mild injuries to teeth are common and cause concussions and subluxations. Concussed teeth are essentially injured, nonmobile, and nonfractured teeth. These teeth have suffered a direct blow and are sensitive, with no concrete clinical or radiographic
FIGURE 181-2. The dental anatomic unit (i.e., the tooth) and its supporting structures.
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evidence of injury. Concussions are often mild injuries to the periodontal ligament with associated inflammation. Subluxed teeth may or may not be sensitive, are not displaced, but are perceptively mobile when manipulated between two cotton applicators or other instruments. Subluxations have definite damage to the periodontal ligament with associated inflammation. Mild gingival bleeding may be present. Both concussion and subluxation imply an injury to the attachment apparatus. Pain control, soft diet instructions, and follow-up with a Dentist are all that is required in the management of most of these injuries. Concussed and subluxed primary and permanent teeth are generally treated in the same manner.2,7–9,16 Excessive mobility from a severe subluxation may be irritating, painful, and damaging. These injuries require a temporary splint for relief.2,3,5–9 Definitive treatment for severely subluxed permanent teeth requires splinting for 2 weeks or more.9,16 Definitive treatment for severely subluxed primary teeth is extraction.9,16
LUXATED TEETH Luxated teeth are displaced or dislocated from their usual position within the alveolar bone. The periodontal ligament is torn. Luxated teeth are commonly associated with other injuries such as alveolar fractures, root fractures, and gingival lacerations.2,17 Subcategories of injury within this class are described by the direction of the dislocation. Luxated teeth may be displaced laterally, intruded, or extruded (Figure 181-3). Lateral luxations may be mesial, distal, buccal, or lingual in direction. An alveolar fracture is self-evident when several teeth are luxated as a solid segment. Laterally luxated permanent teeth should be repositioned and temporarily splinted.7–9 Laterally luxated primary teeth can be treated in the same fashion.16 A general word of caution regarding primary teeth is warranted. The apices of the primary teeth are in close anatomic proximately to the developing permanent tooth buds within the alveolus. This close relationship can lead to numerous developmental disturbances in the permanent dentition whenever there is trauma to a primary tooth.18 Therefore, it is recommended that the Emergency Physician defer any manipulation of a primary tooth to the care of a Dentist, or at least consult them first. Extruded teeth represent a partial avulsion from the alveolar socket and a damaged attachment apparatus. They typically appear clinically longer than the surrounding teeth (Figure 181-3B). Patients may complain of occlusal prematurity. There may be
FIGURE 181-3. Luxation injuries with neurovascular damage to the apex. A. Intrusive luxation injury. B. Extrusive luxation injury.
associated gingival bleeding. A hematoma surrounding the apex may preclude complete repositioning. Extruded permanent teeth are treated with repositioning and temporary splinting.2,3,5,7–9 Treatment decisions for extruded primary teeth are complex and best left to a Dentist. The majority of these teeth will likely require extraction.16 Intrusion is a severe form of luxation injury with the tooth driven inward in an axial direction. These injuries are manifested by displacement of the tooth into the alveolar socket with a corresponding fracture of the alveolar bone surrounding the apex (Figure 181-3A). Adjacent structures, such as the floor of the nose or maxillary sinus, may be involved or damaged.13,14 These injuries may be so profound that the tooth is not visible within the oral cavity and believed to be avulsed. It is worth reiterating that a tooth that cannot be unequivocally located on physical examination requires radiographic localization. Immature adult teeth suffering intrusion injuries generally have the best prognosis. They are often left alone and allowed to re-erupt. Mature adult teeth often require surgical or orthodontically assisted re-eruption and root canal therapy. The intrusion of primary teeth frequently leads to damage of the developing permanent tooth buds and requires close dental follow-up. Rule out more serious injuries, arrange an expedited appointment for definitive care, prescribe appropriate analgesics, and give strong consideration to the prescription of antibiotics.2,3,5,7–9,19
AVULSED TEETH Avulsed teeth are teeth that have been completely torn from their alveolar sockets. The teeth have suffered profound attachment and neurovascular damage that progresses in a time-dependent fashion. There is a high likelihood of associated injuries with this type of trauma. Perform a thorough evaluation of the entire oral cavity after any dried blood, clots, and debris have been removed. Bleeding can generally be controlled with firm digital pressure or local infiltration of an epinephrine-containing local anesthetic solution. Patients may present with the tooth in hand or may not be aware of the location of the tooth. The onus is on the Emergency Physician to determine the exact whereabouts of the tooth. Treat the patient for pain, control the bleeding, and provide tetanus prophylaxis. Prescribe antibiotics for these patients if there are significant concomitant injuries or as the situation warrants. Arrange follow-up with a Dentist at their convenience. If available, a permanent tooth can be treated with replantation. As a rule, avulsed primary teeth are not replanted to avoid damage to the developing permanent teeth and possible growth disturbances.5,7,8,16 Exercise great care in evaluating patients in the mixed dentition stage, roughly between the ages of 6 and 12 years.2,3,5 An attempt can be made at replantation in order to preserve patient comfort, cosmesis, and function when a permanent avulsed tooth is available. The objective for the emergency treatment of these injuries is to maintain viability of the torn periodontal ligament fibers on the external root surface as pulpal necrosis is inevitable for the majority of these teeth.2 A successfully replanted tooth may be fully functional with little or no cosmetic impact following root canal therapy. Periodontal ligament fibers are extremely sensitive to desiccation. The most critical factor in the successful replantation of avulsed teeth is the speed with which the tooth is replanted.2,3,17,20 Patients, parents, or Emergency Medical Service (EMS) personnel can be instructed to replant an avulsed tooth in the field in order to improve the prognosis.2,3 Take great care in the handling of an avulsed tooth. They should be handled minimally and only by the crown. The root
CHAPTER 181: Subluxed and Avulsed Tooth Management
surface should not be manipulated in any way other than gentle cleansing with sterile saline, or tap water as a substitute. This will prevent further damage to the cementum and periodontal ligament. Treat the socket in a similar fashion (i.e., cleansed of any obstructing clots or debris with gentle irrigation and suction only) following anesthesia.3,20 When it is not possible to immediately replant an avulsed tooth, it can be transported or stored in such a way as to prevent desiccation of the fragile periodontal ligament fibers and to improve salvage rates.2,5,7–9 The best possible transport and storage solutions are Hank’s balanced salt solution (HBSS) and Viaspan, a special cell culture medium (SCCM) used to preserve transplant tissues. The SCCM seems to show some benefit over HBSS.22 Several commercial products are readily available and specifically designed for tooth transportation and storage. They include EMT Tooth Saver (SmartPractice, Phoenix, AZ) and Dentosafe (Medice, Iserlohn, Germany) which utilize SCCM, or Save-aTooth (Phoenix-Lazerus, Pottstown, PA) which utilizes HBSS.22 These products have great utility in the field and the Emergency Department. They should be considered standard and essential equipment for the Emergency Department. This is particularly true where definitive dental care is not readily available. Simply providing a patient with one of these products may allow successful replantation by a dental specialist hours or even days later.2,23 Fresh pasteurized whole milk and sterile normal saline are alternatives, but carry diminishing returns for tooth salvageability. Saliva can be employed as a transport medium (by placing the tooth in the buccal vestibule of a conscious and cooperative adult) for very brief periods, again with diminishing hopes for salvage. Tap water or plastic wrap may prevent desiccation for a brief period if all else fails.3,5,7–9,23 The literature indicates that irreversible periodontal ligament cell damage occurs within minutes following total tooth avulsion.3,5,20 Common clinical practice is typically to abandon attempts at salvageability if the tooth has been out of the socket for more than an hour. However, the notion that replantation is not possible for extraoral times beyond 1 hour is a myth. The dental trauma literature is replete with case reports with successful outcomes following very long extraoral times (up to a week) and under extremely suboptimal storage conditions such as being kept completely dry.23,24 An esthetic and functional, albeit less than ideal, result may be possible for avulsed teeth with extraoral times over an hour through a process known as ankylosis if appropriately and aggressively treated by a skilled Dentist. Therefore, it is never acceptable to discard an avulsed tooth. Avulsed teeth with extraoral times greater than 1 hour require special treatment with topical fluoride and antibiotic soaks that are typically beyond the scope of care in the Emergency Department.9,20 Consult a Dentist prior to considering these techniques. At the very least, always give the patient their tooth back in a suitable storage/transport device and advise them on their options for definitive care.
REDUCTION OF SEVERELY SUBLUXED, LATERALLY LUXATED, AND EXTRUDED TEETH The emergent treatment of a severely subluxed tooth, a laterally luxated tooth, or an extruded tooth involves obtaining adequate anesthesia, reduction of the tooth, and a temporary splint for stabilization.
INDICATIONS Any severely subluxed, laterally luxated, or extruded tooth is a candidate for reduction.
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CONTRAINDICATIONS There are no absolute contraindications to the reduction of a subluxed, laterally luxated, or extruded permanent tooth. Laterally luxated and primary teeth can be repositioned and splinted. However, their manipulation may damage the permanent tooth bud growing beneath the primary tooth root. Therefore, all subluxed, luxated, or extruded primary teeth should be considered for extraction in consultation with a Dentist or Oral Surgeon.5,7,8,16,17,21 Consult a Dentist or Oral Surgeon if there is a significant alveolar bone fracture. Do not attempt to reduce teeth that are fractured or grossly carious.
EQUIPMENT • Local anesthetic solution, with and without epinephrine • Dental aspirating syringe or a 3 mL syringe with a 2 inch, 25 to 27 gauge needle • Sterile saline • Sterile 2 × 2 gauze squares • Suction source and tubing • Frazier suction catheter • Cotton-tipped applicators • Overhead lighting or headlight
PATIENT PREPARATION Explain the procedure, its risks, and benefits to the patient and/ or their representative. Obtain a signed informed consent for the procedure. Place the patient in a multipositional procedure chair with good overhead lighting. Administer dental anesthesia. Refer to Chapter 176 regarding the details of dental anesthesia and analgesia. Cleanse the oral cavity with warm saline or tap water and gentle suction. Thoroughly examine the entire oral cavity. Obtain radiographs as indicated. Provide tetanus prophylaxis if required.
TECHNIQUES ■ SEVERELY SUBLUXED TOOTH REDUCTION A severely subluxed tooth is not displaced from its socket but is excessively mobile. Ensure that the tooth is in its proper anatomic location. Apply a temporary dental splint, as described below.
■ LATERALLY LUXATED TOOTH REDUCTION A laterally luxated tooth has its roots displaced laterally and out of the socket (Figure 181-4). It is often associated with a fracture of the surrounding alveolar bone. Place the dominant thumb over the medial surface of the tooth and the index finger overlying the root end of the tooth (Figure 181-4). Apply downward and inward pressure with the index finger (Figure 181-4A) followed by application of outward pressure with the thumb (Figure 181-4B) to reduce the tooth. Apply a temporary dental splint, as described below.
■ EXTRUDED TOOTH REDUCTION An extruded tooth is a partially avulsed tooth that protrudes above the adjacent teeth. Apply gentle pressure to the crown of the tooth to reduce the tooth. Do not force the tooth into the socket to avoid an iatrogenic fracture at its base. Consult a Dentist if the tooth will not reduce. A hematoma in the base of the socket often prevents reduction. Insert a piece of gauze over the tooth and instruct the patient to gently bite down.
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expedite the care of these patients. Replantation consists of gently reinserting the tooth in the proper orientation and fully seating it with gentle pressure.
INDICATIONS Any intact and avulsed permanent tooth is a candidate for replantation.
CONTRAINDICATIONS There are no absolute contraindications to the replanting of permanent teeth by nondental personnel. Concerns for the ABC’s (airway, breathing, and circulation), concomitant major morbidity, and aspiration risk in acutely or chronically debilitated patients should be considered prior to tooth replantation. Primary teeth are never replanted. Do not attempt to replant teeth that are fractured or grossly carious.
EQUIPMENT FIGURE 181-4. Manually repositioning a laterally luxated tooth. Apply downward and inward pressure with index finger (A) followed by outward pressure with the thumb (B).
ASSESSMENT Obtain postreduction radiographs to verify the correct tooth position. Radiographs may be delayed until after splinting. Reassess the patient for pain, occlusal discrepancies, and stability of the reduction. Manage any soft tissue injuries.
AFTERCARE Prescribe appropriate analgesics. Nonsteroidal anti-inflammatory drugs supplemented with occasional narcotic analgesic will provide adequate analgesia. Prescribe empiric antibiotics (penicillin or clindamycin). Twice daily rinses with chlorhexidine may also be useful. Instruct the patient to avoid extremely hot or cold substances, to eat a liquid or soft diet, and to avoid chewing in the area of the injury. Provide specific instructions regarding interim dental splint care as discussed below. Arrange follow-up with a Dentist or Oral Surgeon within 24 hours. Remind the patient that any dental injury can result in the loss of tooth vitality and, ultimately, the loss of the tooth despite the best of efforts to maintain it.2,3,19
COMPLICATIONS Immediate complications of any dental trauma include pain and cosmetic deformity. Additionally, instability may be an issue following the application of a temporary splint. Delayed complications can be variable and include tooth mobility, root resorption, pulpal necrosis, infections, and abscess formation. Extension of untreated infections into alveolar bones can cause osteomyelitis and/or systemic infectious complications. A permanent tooth may develop abnormally in a younger child if injured. Bleeding is minimal and often self-limited. Refer to Chapter 179 for the details of post-extraction bleeding management. Ensuring prompt dental follow-up, adequate outpatient analgesics, and empiric antibiotics can limit most of these complications.
REPLANTATION OF AN AVULSED TOOTH Permanent teeth that have been avulsed should be handled gently and only by the crown. Time is a critical factor in the successful treatment of these injuries and every effort should be made to
• Local anesthetic solution, with and without epinephrine • Dental aspirating syringe or a 3 mL syringe with a 2 inch, 25 to 27 gauge needle • Sterile saline • Hank’s balanced salt solution • Sterile 2 × 2 gauze squares • Sterile cotton rolls • Suction source and tubing • Frazier suction catheter • Cotton-tipped applicators • Overhead lighting or headlight
PATIENT PREPARATION Explain the procedure, its risks, and benefits to the patient and/ or their representative. Obtain a signed informed consent for the procedure. Place the patient in a multipositional procedure chair with good overhead lighting. Administer dental anesthesia. Refer to Chapter 176 regarding the details of dental anesthesia and analgesia. Cleanse the oral cavity with warm saline or tap water. Use gentle suction, but never near the injured tooth. Thoroughly examine the entire oral cavity. Obtain radiographs as indicated. Provide tetanus prophylaxis if required. Gently irrigate the avulsed tooth and socket with warm sterile saline or Hank’s solution. Remove and clots and debris using a Frazier suction catheter. Take great care to avoid touching or contaminating the tooth root. Soak the tooth in Hank’s solution for 30 minutes prior to replantation if the extraoral dry time exceeds 30 minutes. Consult a Dentist skilled in dental trauma care prior to replanting if the extraoral time exceeds 1 hour.
TECHNIQUE Grasp the avulsed tooth gently and only by the crown. Replace the avulsed tooth into the socket in an anatomically correct position. Seat the tooth fully with gentle but firm digital pressure. Never force the tooth into the socket. Evaluate the patient’s occlusion. Instruct the patient to gently bite together several times while observing for any prematurity. Occasionally, a tooth cannot be completely seated or its position is uncertain. Instruct the patient to temporarily bite on a gauze roll until the dental specialist arrives or store the tooth in a storage/transport media until definitive dental
CHAPTER 181: Subluxed and Avulsed Tooth Management
care can be rendered.3,19 Address any soft tissue injuries once the tooth’s position has been verified. Insert a piece of gauze over the tooth and instruct the patient to gently bite down. Apply a temporary dental splint, as described below.
ASSESSMENT Obtain post-replantation radiographs to verify the correct tooth position. Radiographs may be delayed until after splinting. Reassess the patient for pain, occlusal discrepancies, and stability of the replanted tooth prior to discharge. Manage any soft tissue injuries.
AFTERCARE Prescribe appropriate analgesics. Nonsteroidal anti-inflammatory drugs supplemented with occasional narcotic analgesic will provide adequate analgesia. Prescribe empiric antibiotics. Doxycycline is recommended as the drug of choice in patients over 12 years of age. Penicillin or clindamycin are useful substitutes. Twice daily rinses with chlorhexidine are useful, but not required. Instruct the patient to avoid extremely hot or cold substances, to eat a liquid or soft diet, and to avoid chewing in the area of the injury. Provide specific instructions regarding interim dental splint care as discussed below. Arrange follow-up with a Dentist or Oral Surgeon within 24 hours. Remind the patient that any dental injury can result in the loss of tooth vitality and, ultimately, the loss of the tooth despite the best of efforts to maintain it.2,3,19
COMPLICATIONS Immediate complications of any dental trauma include pain and cosmetic deformity. Additionally, instability may be an issue following the application of a temporary splint. Delayed complications can be variable and include tooth mobility, root resorption, pulpal necrosis, infections, and abscess formation. Extension of untreated infections into alveolar bones can cause osteomyelitis and/or systemic infectious complications. A permanent tooth may develop abnormally in a younger child if injured. Bleeding is minimal and often self-limited. Refer to Chapter 179 for the details of post-extraction bleeding management. Ensuring prompt dental follow-up, adequate outpatient analgesics, and empiric antibiotics can limit most of these complications.
PREPARING A TEMPORARY DENTAL SPLINT Concussed teeth, subluxed primary teeth, and subluxed permanent teeth usually do not require splinting. A temporary splint may prevent further damage and improve patient comfort if severe mobility, or subluxation, is present. Manually reposition laterally luxated and extruded permanent teeth using gentle and firm digital manipulation following adequate anesthesia. A Dentist or Oral Surgeon will typically extract laterally luxated or extruded primary teeth. Intruded teeth, both primary and adult, are associated with considerable comorbidity and complications. These injuries require consultation with a Dentist or Oral Surgeon after defining the extent of the injuries with appropriate radiographs.
INDICATIONS Any severely traumatized and grossly mobile, luxated, repositioned, or replanted tooth requires temporary splinting. This will prevent further damage, promote patient comfort, preserve form, and preserve function.
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CONTRAINDICATIONS There are no absolute contraindications to the temporary splinting of mobile teeth. The aspiration risk in acutely or chronically debilitated patients should be considered prior to tooth splinting.
GENERAL SPLINTING EQUIPMENT • Local anesthetic solution, with and without epinephrine • Dental aspirating syringe or a 3 mL syringe with a 2 inch, 25 to 27 gauge needle • Sterile saline • Coe-Pak or Perio-Pak • Dental utility wax or beeswax • Sterile 2 × 2 gauze squares • Sterile cotton rolls • Applicator sticks; tongue depressors or the wooden end of cotton swabs will substitute • Frazier suction catheter • Suction source and tubing • Overhead lighting or headlight
ADVANCED SPLINTING EQUIPMENT • • • • • • • • •
General splinting equipment as described above Wire cutters Tooth etching gel Composite resin material (e.g., Centrix Tempit Ultra-F, Centrix Inc., Shelton, CT) Single-component adhesive (e.g., Optibond Solo Plus kit, Kerr Corp., Orange, CA) Bondable reinforcement ribbon (e.g., Ribbond, Ribbond Inc., Seattle, WA) Orthodontic wire, 0.025 inch Tubing and regulator to attach to wall air supply Visible curing light
PATIENT PREPARATION Explain the procedure, its risks, and benefits to the patient and/ or their representative. Obtain a signed informed consent for the procedure. Place the patient in a multipositional procedure chair with good overhead lighting. Administer dental anesthesia. Refer to Chapter 176 regarding the details of dental anesthesia and analgesia. Cleanse and thoroughly examine the entire oral cavity. Obtain radiographs as indicated. Provide tetanus prophylaxis if required. Manually reposition any luxated and avulsed teeth. Manage any soft tissue injuries prior to splint placement to avoid wound contamination by the splint material.
TECHNIQUES Cold-curing periodontal packing material (i.e., Coe-Pak or PerioPak) is an ideal splinting material for practitioners without dental experience. Measure out equal amounts (i.e., lengths) of the catalyst and the epoxy onto a paper pad (Figure 181-5A). Usually a 2- to 3-inch ribbon of each substance is adequate. Thoroughly mix the catalyst and epoxy compounds together with a tongue depressor to form a putty-like consistency (Figure 181-5B). Using tap water- or saline-wetted gloved hands, roll the material into a log (Figure 181-5C). Apply the material to frame both aspects, medial
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FIGURE 181-5. Preparation of the dental bonding resin and repair of the injured tooth. A. Equal amounts of the epoxy and catalyst are measured. B. The epoxy and catalyst are mixed together. C. The hardening dental paste is molded into a supportive bridge. D. The dental bridge is applied over the injured tooth and adjacent two uninjured teeth (both sides) for support while hardening.
and lateral, of the injured tooth and two to three adjacent stable teeth on either side of the injured tooth (Figure 181-5D). Use finger pressure to squeeze the material between the teeth medially and laterally to create a single splint unit. To allow proper occlusion, do not place the packing material on the masticatory surfaces of the teeth. The material must be kept dry and uncontaminated to cure, which is achieved within minutes.
ALTERNATIVE TECHNIQUES Numerous alternative techniques have also been used to temporarily splint a tooth. A simpler technique employs softened dental utility wax or beeswax in a similar fashion as described above. The wax splint is not nearly as stable as the cold-curing periodontal packing. Both the medial and lateral surfaces of the teeth can be splinted in this fashion. Ligature splinting with suture material has been described, but rarely provides any significant stability. Advanced techniques include bondable reinforcement ribbon, acid-etched composite resin, direct interdental wiring, resin-wire combinations, arch bars, and stabilization with a figure-of-eight stitch to the adjacent tooth. These are excellent materials in experienced hands. Unfortunately, they are difficult to use, fraught with complications, and cost prohibitive for routine Emergency Department use.2,3,5,6,15,17,19,21 Two of these methods, which can be performed by the Emergency Physician if supplies are available, are described below. In an emergency with no immediate dental supplies or a Dentist, skin wound glue (2-octyl cyanoacrylate) and a metal nasal bridge from a face mask have been used to splint a tooth.25 A tooth may be splinted using bondable reinforcement ribbon. Open the Ribbond kit. Use the included scissors to cut a piece of the splinting fabric long enough to span the length of the injured tooth and one tooth on each side of the injured tooth. Apply a small
drop of the acid etching solution onto all three teeth (the injured tooth, the one behind it, and the one in front of it). Allow the acid etching solution to remain on the teeth for 20 seconds. Thoroughly and gently rinse the acid etching solution using warm tap water or warm sterile saline in a syringe while using suction to capture the liquid. It is often easier to etch and rinse one tooth at a time instead of all three simultaneously. Thoroughly dry the teeth with compressed air. Remove the Optibond Solo Plus container from its packaging. Twist and remove the tip from the Optibond Solo Plus container. Apply a layer of the Optibond Solo Plus to the etched surface of all three teeth using the kits microbrush. Apply the curing light to the three teeth for 20 seconds each. Apply the Optibond Solo Plus onto the previously cut splinting fabric until it is saturated. Apply the tip onto the syringe containing the composite resin. Apply the composite resin to each of the three teeth. Apply and embed the splinting fabric into the composite resin on each tooth. Use a wooden stick (e.g., tongue depressor or cotton-tipped applicator) to ensure that the fabric is embedded in the resin as well as covered by the resin. Apply the curing light onto the three teeth for 40 seconds each. The procedure is the same if multiple adjacent teeth require splinting. A tooth may be splinted using wire and composite resin. Use a wire cutter to cut a piece of orthodontic wire long enough to span the length of the injured tooth and one tooth on each side of the injured tooth. The remainder of the procedure is exactly as described above except the orthodontic wire is substituted for the splinting fabric.
ASSESSMENT Allow the patient to wait in the Emergency Department until the splinting material has hardened. The splint material should impinge minimally on the soft tissues. The patient must be able to
CHAPTER 182: Fractured Tooth Management
open and close their mouth and lips freely, without any obstruction. Reassess the patient for pain, occlusal discrepancies, and stability of the replanted or subluxed tooth prior to discharge. Obtain post-splinting radiographs to verify the proper tooth position.
Primary dentition Age of primary tooth eruption (months)
Adult (permanent) dentition Age of permanent tooth eruption (years) 8–9
12–18
Prescribe appropriate analgesics. Nonsteroidal anti-inflammatory drugs supplemented with occasional narcotic analgesic will provide adequate analgesia. Prescribe empiric antibiotics. Instruct the patient to avoid extremely hot or cold substances, to eat a liquid or soft diet, and to avoid chewing in the area of the injury. Provide specific instructions regarding interim dental splint care. Arrange follow-up with a Dentist or Oral Surgeon within 24 hours. Remind the patient that any dental injury can result in the loss of tooth vitality and, ultimately, the loss of the tooth despite the best of efforts to maintain it.2,3,19
Maxillary teeth
7–8
AFTERCARE
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11–12
9–11
10–11
16–22
10–12
13–19
6–7 25–33 12–13
COMPLICATIONS The complications of temporary dental splinting are minimal. The splint material may not stabilize the tooth. A tooth allowed to move within the socket may result in damage to the cementum or the periodontal ligament. An improperly splinted tooth may fall out and result in an aspiration risk. To prevent irritation and bleeding, do not apply splinting materials over the soft tissues. Do not leave the etching acid on longer than 20 seconds or it can penetrate too deep and damage the tooth.
11–13 23–31 6–7 14–18 17–23 10–16
SUMMARY Traumatic dental injuries are a common presentation to the Emergency Department, especially in pediatric patients during the mixed dentition stage. These injuries may have significant cosmetic, functional, and psychological consequences for the rest of the patient’s life. The appropriate Emergency Department management of dental trauma depends heavily upon the type of tooth involved (primary vs. permanent), the time elapsed since the incident, and the extent of the damage. A basic understanding of dental anatomy, terminology, pathophysiology, and treatment protocols will facilitate an accurate description of the extent of the injuries to the dental consultant and be of great aid in providing temporizing emergent dental care when no specialist is readily available.
182
Fractured Tooth Management Daniel J. Ross
INTRODUCTION Traumatic dental injuries are common and can have significant lasting consequences for the patient. Recent estimates indicate over three quarters of a million annual Emergency Department visits in the United States for dental-related complaints.1 Nearly 12% of these are related to some form of trauma.1 It has been estimated that approximately 50% of children will sustain traumatic dental injuries, and the majority of these are to the permanent dentition.2–4 Violence of a suspicious nature, such as domestic or child abuse, must always be considered when evaluating dental injuries. The goals of the emergent treatment of dental trauma
11–12 10–12
6–10 6–7
9–10 7–8
Mandibular teeth
FIGURE 182-1. The normal eruptive patterns of the pediatric and adult dentition.
are to maintain patient comfort and tooth vitality, while ensuring prompt dental follow-up for definitive care.
ANATOMY AND PATHOPHYSIOLOGY TOOTH ANATOMY There are significant differences in the adult and pediatric dentitions that impact their treatment in the Emergency Department (Figure 182-1). The pediatric dentition is known as the primary or deciduous dentition and consists of 20 teeth, which includes 8 incisors, 4 canines, and 8 molars. The adult dentition consists of 32 teeth and is composed of 8 incisors, 4 canines, 8 premolars, and 12 molars. The variable absence of a tooth or the addition of an extra tooth is common in either dentition. The teeth in both the pediatric and adult dentitions erupt in a predictable sequence, albeit with considerable individual variation (Figure 182-1). Treatment strategies differ for permanent versus deciduous (primary) teeth as well as by the age of the adult tooth. Exercise great care when evaluating patients with a “mixed” dentition, roughly between the ages of 6 and 12 years. The anatomy of a tooth is rather simple (Figure 182-2). The tooth itself consists of a neurovascular pulp surrounded by supportive dentin, which is surrounded by a hard thick crown of enamel. The crown portion lies above the gum line or gingiva. The root portion lies embedded within the alveolar bone of the jaw, anchored by a thin layer of cementum and the periodontal ligament. The alveolar bone, periodontal ligament fibers, and fragile cementum cell layer taken together are considered a functional unit known as the attachment apparatus. A complete attachment apparatus requires a fully
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FIGURE 182-2. The dental anatomic unit (i.e., the tooth) and its supporting structures.
formed root apex. Immature adult teeth do not have a fully formed apex and necessitate special attention to maintain pulpal viability.2,4,5
TOOTH INJURY Mechanisms of tooth injury include direct trauma (i.e., a blow) or occlusive trauma (i.e., biting on a hard object or a seizure). These mechanisms can result in a spectrum of injury patterns that vary from simple sensitivity to complete tooth avulsion. The fracture of any portion of the tooth, whether the crown or the root, falls in the middle of this spectrum and is frequently seen in the Emergency Department.4 Appropriate treatment of dental injuries requires a thorough history and meticulous examination of the oral cavity, including subsequent radiographs after ruling out more serious injuries. Historically, important points include the age of the patient, the time of the trauma, the mechanism of injury, teeth or tooth pieces at the scene, subjective disturbance of bite, and treatments provided since the time of the incident. The physical examination must include an assessment of the extraoral and intraoral soft tissues, bony displacement, missing teeth, crown fractures, pulp exposures, tooth sensitivity, and tooth mobility. This chapter focuses primarily on tooth fractures, while luxation and avulsion injuries are dealt with in Chapter 181. The need for radiographs with dental trauma is worth emphasizing. A tooth that is missing, both by history and physical examination, may be found completely intruded below the gum line, impacted within the perioral soft tissues, floating within the maxillary sinus or stomach, or even aspirated. Obtain facial films if a tooth, or a portion of a tooth, cannot be unequivocally located by history or physical examination. Strongly consider obtaining chest and abdominal radiographs if the tooth, or portion in question, is not visualized on the facial films.6–11 Any available tooth fragments, whether retrieved from the scene, the patient’s perioral soft tissues, or the patient’s pocket should be saved and stored for potential use during the definitive care process by the Dentist.9,12–14 Bonding techniques in the Emergency Department are not prudent due to multiple potential complications including bond failure and tooth fragment aspiration.
TOOTH FRACTURES Fractures involving the crown of the tooth are commonly described in the emergency literature using the Ellis classification system (Figure 182-3).2,4–6,15,16 An Ellis I fracture involves only the enamel portion of the tooth. These injuries typically are not sensitive or
FIGURE 182-3. The Ellis classification scheme of dental fractures through the crown.
CHAPTER 182: Fractured Tooth Management
painful. They can result in a sharp edge of enamel that may irritate the tongue and other adjacent soft tissues. Emergency treatment may be as simple as smoothing the rough edge with an emery board or similar instrument.2,4,14,17 These injuries frequently involve the prominent anterior teeth and may be cosmetically unappealing. Reassure patients with these concerns that aesthetic restorations are possible by their Dentist.4–6,15,18 Forewarn patients with even minor trauma and sensitivity that unseen or undiagnosed trauma at the apex of any traumatized tooth, even with an appropriately treated crown fracture, can compromise the blood flow to the pulp and obviate the need for root canal therapy.4,18 Both primary and permanent teeth with these fractures can be treated in a similar fashion.14,19 The Ellis II fracture involves the dentin. It can be recognized by the yellow to pink hue of the dentin in contrast to the white of enamel. This fracture allows for potential contamination of the dentin microtubular networks by oral bacteria that may eventually compromise the pulp if not treated. Dentin is alive and formed by the pulp. It is sensitive to temperature, osmotic gradients, and mechanical forces. Dentin is laid down concentrically from within the pulp chamber as the tooth ages. Therefore, children have less dentin than pulp (as compared to adults) and their pulp is less insulated against trauma and subsequent infection. Children under the age of 12 years with Ellis II fractures have a higher risk of complications and require more expeditious follow-up.2,5,14,18 Refer these patients to a General or Pediatric Dentist as soon as possible. Emergency treatment for Ellis II fractures consists of applying a protective dressing which is also sedative to the pulp. Examples include Dycal (L.D. Caulk Co., Milford, DE) and IRM (L.D. Caulk Co., Milford, DE). These materials need to cover the entirety of exposed dentin (and therefore the dentinal tubules) in order to protect the pulp from contamination. These materials are then often covered with a sealant such as Copalite (Cooley & Cooley, Houston, TX), clear acrylic nail polish, or a dental bonding resin.2,3,5,6,14,15,18,20 Some authors have suggested that a non-light cured glass ionomer cement replace the long held standard of Dycal.3 While these materials may offer some advantages, they can be expensive and tricky to use.18 Tissue adhesives such as Dermabond (Ethicon, Inc., Somerville, NJ) have been suggested as alternative dressings in the treatment of Ellis II dental fractures.21–23 This should be discouraged as its effects on pulpal tissues via exposed dentinal tubules have not been studied and are unknown. Physicians may actually be causing harm by using this material on exposed dentin. Both primary and permanent teeth with Ellis II fractured can be treated in a similar fashion. However, like immature permanent teeth, primary teeth with Ellis II fractured require special care and more expeditious follow-up.14,19 The Ellis III fracture involves exposure of both the dentin and the pulp. This is identified as a reddish tinge or subtle bleeding from the exposed dentin. Frank pulpal exposures are obvious. The pulp is highly vascular and exquisitely sensitive due to exposed nerve endings. The pulp is exceedingly vulnerable to bacterial infection if exposed. These fractures constitute a true dental emergency and should be evaluated immediately by a Dentist for possible emergent root canal therapy or extraction. Although less than ideal, minimal pulp exposures (less than 1 to 2 mm) may be treated as Ellis II fractures with dental follow-up within 24 hours.2–6,14,15,18,19 Complete coverage of the fractured crown may be difficult in these cases. Dental dry foil or tin foil may provide adequate coverage. Any root canal manipulation is fraught with complications, even in the hands of Endodontists. Emergency Physicians are well advised to avoid these procedures.2,15,18 Fractures of the root are much less common than crown fractures and occur in less than 7% of dental injuries.2,4 Root fractures are
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FIGURE 182-4. Classification of root fractures according to their location. A. Incisal or coronal third fracture. B. Mid-root fracture. C. Apical third fracture.
uncommon in primary teeth as they have short roots.2 Root fractures may be described as either horizontal or vertical. Horizontal root fractures are described according to their location along the tooth root (Figure 182-4). Vertical root fractures occasionally extend into the crown. All root fractures are prone to infection and impaired healing, and may ultimately lead to pulpal necrosis and tooth loss. The clinical diagnosis of root fractures is challenging at best, even with the aid of radiographs readily available in the Emergency Department setting (i.e., Panorex). Root fractures classically present with pain, mobility, and sometimes displacement of a tooth fragment. However, these fractures are often insidious and found only on dental radiographs after follow-up reveals continued sensitivity. Emergency Physicians must maintain a high level of clinical suspicion for these injuries and probably err on the side of cautious overtreatment.2,4 Vertical root fractures and root fractures in the coronal portion of the root have a poor prognosis. Horizontal root fractures elsewhere along the tooth root have a good prognosis if treated before a coagulum can develop between the fragments, generally within 24 to 72 hours.2,15 Immediate reduction and immobilization with one of the various splinting techniques is the treatment of choice. Refer to Chapter 181 for the details regarding dental splinting techniques. Root fractures in the primary teeth require extraction.19
INDICATIONS Fractured teeth may require no treatment or a significant amount of treatment based upon the type of injury as described by the Ellis classification system. Fractured roots must be treated based upon the level of clinical suspicion.
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CONTRAINDICATIONS There are no absolute contraindications to the temporary repair of a fractured tooth or tooth root. Concerns for the ABC’s (airway, breathing, and circulation), concomitant major morbidity, and aspiration risk in acutely or chronically debilitated patients should be considered prior to tooth repair.
EQUIPMENT • Local anesthetic solution, with and without epinephrine • Dental aspirating syringe, or a 3 mL syringe, with a 2 inch, 25 to 27 gauge needle • Dental explorer • Discoid-cleoid carver • Dental drill or emery board • Sterile saline • Sterile 2 × 2 gauze squares • Sterile cotton rolls • Applicator or molding sticks; tongue depressor or the wooden end of cotton swabs will substitute • Calcium hydroxide paste (e.g., Dycal), mixable or premixed (preferred) • Copalite cavity varnish or clear acrylic nail polish • Zinc oxide—eugenol paste (e.g., ZOE or IRM) • Dental dry foil or tin foil • Frazier tip suction catheter • Suction source and tubing • Good overhead lighting or headlight • Dental floss
PATIENT PREPARATION Explain the risks, benefits, and aftercare to the patient and/or their representative. Obtain an informed consent for the procedure. Position the patient upright in a multipositional procedure chair in a well-lighted environment. Provide tetanus prophylaxis as required. Provide anesthesia to the patient. Refer to Chapter 176 for the complete details regarding dental anesthesia and analgesia. Irrigate the oral cavity and dental repair region with warm saline to remove any gross contaminants or clotted blood. Warm gentle irrigation is usually less sensitive to exposed dentin.15 A dry and uncontaminated field is mandatory. This can be achieved via dabbing with sterile cotton pellets or gently blowing with compressed air. Maintain a dry working environment by isolating the traumatized tooth with sterile cotton rolls on either side. Inject a small amount of local anesthetic solution containing epinephrine directly into the pulp if continued bleeding from a large pulpal exposure is problematic.
TECHNIQUES ELLIS I FRACTURES Ellis I fractures are clinically minor injuries. The management includes smoothing of any sharp edges with a dental drill or a nail file to prevent injury or irritation to the soft tissues of the oral cavity. Use care to avoid over-aggressive smoothing and exposure of the dentin (i.e., iatrogenic Ellis II injury).
ELLIS II FRACTURES Ellis II fractures are clinically more important than Ellis I fractures. They require coverage of the exposed dentin to prevent infection and reduce sensitivity. Paint small or large dentinal exposures with calcium hydroxide paste covering all of the exposed dentin.6,15,17 Apply the premixed calcium hydroxide paste in a thin layer with any small, blunt instrument or the wooden handle of a cotton-tipped applicator. If not premixed, apply equal amounts of the calcium hydroxide base and catalyst on a piece of paper. Mix these two components thoroughly with a blunt instrument or wooden stick and then apply it to the tooth. Allow the calcium hydroxide paste to dry. Apply three to four coats of cavity varnish or clear acrylic nail polish over the dry calcium hydroxide paste. Allow adequate drying time between the coats. This will relieve any sensitivity. Alternatively, place a tin foil dressing over the tooth to act as a bandage following placement of the calcium hydroxide paste.6,15,16 With cautious care, a calcium hydroxide dressing will typically last 2 to 3 days.18
ELLIS III FRACTURES Ellis II fractures are true dental emergencies and should be treated by a Dentist or Oral Surgeon. Treat pulpal exposures, if no specialist is immediately available, by applying a saline-moistened or lidocaine-moistened cotton pledget over the exposed pulp and holding it there until the bleeding stops. This may take 2 to 5 minutes. Apply a thick mixture of calcium hydroxide paste over the exposed pulp and dentin. Apply the calcium hydroxide paste over an adjacent tooth to form a temporary hold. Contour the calcium hydroxide paste so that it does not irritate the surrounding tissue. The majority of these injuries will require root canal therapy. Refer the patient to a Dentist within 24 hours if they are not seen in the Emergency Department.
ASSESSMENT Reassess the patient for pain and any occlusal discrepancies prior to discharge.
AFTERCARE Most of these patients will have some degree of sensitivity until definitive treatment by a Dentist. Prescribe appropriate outpatient analgesics. Nonsteroidal anti-inflammatory drugs supplemented with a narcotic analgesic will provide adequate pain control for Ellis II and III fractures. Antibiotics are generally not necessary unless the initial presentation had been significantly delayed, suppuration is present, or a significant delay is expected in obtaining dental follow-up. Instruct the patient to avoid extremely hot or cold substances, to begin a liquid or soft diet until seen by a Dentist, to avoid chewing in the area of the injured tooth, and to avoid topical analgesics (such as oil of cloves) due to the propensity for sterile abscess formation.2,4,15 Always warn patients about continued sensitivity.
COMPLICATIONS Complications of dental trauma include pain, cosmetic deformity, loss of tooth viability, and unsuspected or unrecognized injury to adjacent teeth with later complications. A permanent tooth may develop abnormally in a younger child if injured. Infection can form locally and advance to an abscess, osteomyelitis, and/or systemic infectious complications. Ensuring prompt follow-up with a Dentist can abate the majority of these complications. The Emergency Physician should be ever vigilant for cases suspicious for child abuse or neglect.
CHAPTER 183: Temporomandibular Joint Dislocation Reduction
out of its joint. The mandibular dislocation typically results from TMJ hyperextension or trauma. The Emergency Physician must be able to reduce a TMJ dislocation. The procedure is easy, simple, and straightforward.
SUMMARY Dental fractures are relatively common traumatic injuries. Appropriate clinical assessment and treatment requires an understanding of basic dental anatomy, terminology, and pathophysiology. Management includes addressing patient discomfort, stabilization, and coverage of the exposed vulnerable tooth components. Arrange prompt follow-up with a Dentist for definitive care of any dental injury.
183
ANATOMY AND PATHOPHYSIOLOGY The TMJ is an unusual joint (Figure 183-1). It is composed of two joints separated by an articular disk. The TMJ functions as a hinge and gliding joint. A discussion of the mechanics of the TMJ is beyond the scope of this chapter. Anterior dislocations are most commonly seen in the Emergency Department. The etiology of the dislocation includes laughing, chewing, opening the mouth wide (e.g., eating, for procedures, yawning, vomiting), seizures, and trauma. All of these actions can result in the mandibular condyle sliding forward and anterior to the articular eminence of the temporal bone. Anatomic abnormalities of the TMJ have a greater predisposition for mandibular dislocation. These include a shallow articular eminence, weak or torn temporomandibular ligaments, an overstretched joint capsule, previous TMJ dislocations, or hypermobile syndromes (e.g., Marfan’s or Ehlers-Danlos syndrome).4 The muscular attachments of the mandible result in a pulling of the condyle superiorly and in front of the articular eminence (Figure 183-2). This causes the mandible to become fixed in dislocation and rarely spontaneously reduce.5
Temporomandibular Joint Dislocation Reduction Marilyn M. Hallock
INTRODUCTION Mandible or temporomandibular joint (TMJ) dislocations usually occur in the setting of prior musculoskeletal problems of the jaw.1–3 This includes joint laxity, prior injury or dislocation, inherent hypermobile syndromes (e.g., Marfan, Ehlers-Danlos), or neuromuscular problems (e.g., dystonic reactions) that pull the mandible
A
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B Mandibular fossa
Condyloid process (head)
Temporal bone
Mandibular notch Coronoid process Premolars Molars
Ramus Temporal eminence
Alveolar process Angle
TMJ
Body
Mental foramen Alveolar ridge
Mandibular condyle
C
Articular disc Mandibular fossa Articular Superior joint cavity cartilage
Temporalis muscle
D
Lateral pterygoid muscle
Inferior joint cavity Articular tubercle
External auditory meatus
Lateral pterygoid muscle
Head of mandible Joint capsule Neck of mandible
Canine Incisors
Medial pterygoid muscle
Digastric muscle (posterior belly) Masseter muscle Omohyoid muscle (superior belly)
Digastric muscle (anterior belly)
Sternohyoid muscle
FIGURE 183-1. Anatomy. A. Lateral view of the head and temporomandibular joint. B. Anatomy of the mandible. C. Sagittal section through the temporomandibular joint. D. The attachment of the muscles of mastication to the mandible. The arrows represent the direction of pull of the muscles.
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FIGURE 183-2. Anatomic relationships of the mandible. A. The fully opened mandible. B. An anterior TMJ dislocation.
TMJ dislocations are commonly anterior, but may be in any direction. Anterior TMJ dislocations may occur spontaneously in normal individuals and can occasionally reduce spontaneously. Dislocations of the TMJ are usually bilateral, but can occur unilaterally. Posterior, superior, and lateral dislocations are much more rare. They are seen in the context of direct trauma to the mandible, with or without an associated mandible fracture, cervical spine fracture, or a skull fracture.6,7 The diagnosis can often be made clinically in a cooperative patient with a nontraumatic history. The patient will present in pain with an open mouth, protruding mandible, and malocclusion. A unilateral dislocation will cause the mandible to protrude toward the nondislocated side. A depression, both palpable and visible, will be noted in the preauricular area. The mandible appears symmetrical in bilateral anterior dislocations and deviated to the opposite side of the dislocation in the case of a unilateral anterior dislocation. Mandibular radiographs are indicated when trauma is involved to rule out an associated fracture. The dislocation is often best seen on the Panorex view of the mandible. TMJ views, if available, are also useful. Computed tomography (CT) scanning is warranted if an associated basilar skull fracture, intracranial injuries, or facial fractures are suspected.
• • • •
Gloves Povidone iodine or chlorhexidine solution Local anesthetic solution without epinephrine Equipment and supplies for procedural sedation
PATIENT PREPARATION Explain the procedure, its risks, and benefits to the patient and/ or their representative. Obtain a signed informed consent for the procedure. Place the patient sitting in a multipositional procedure chair with a solid headrest to support their head. Alternatives include placing the patient supine on a gurney or in a chair with an assistant standing behind the patient to stabilize their head (Figure 183-3). The mandible can often be reduced without anesthesia. This is not recommended. Adequate analgesia and muscle relaxation will allow easier manipulation of the mandible back into its anatomic position. Strongly consider the use of parenteral
INDICATIONS Attempt to reduce a closed anterior TMJ dislocation without a concomitant mandible fracture in an alert, cooperative, and consenting patient.
CONTRAINDICATIONS Mandibular dislocations that are open, superior in direction, lateral in direction, or posterior in direction require an Oral Surgeon or Otolaryngology consultation prior to reduction attempts. Dislocations, regardless of the direction, associated with mandible fractures require consultation prior to reduction attempts. The inability to reduce an anterior mandible dislocation by the closed method requires consultation and reduction under general anesthesia. Patients presenting with cranial nerve injuries associated with the dislocation require emergent consultation prior to the reduction.
EQUIPMENT • 25 gauge needle • 3 mL syringe • Gauze 4 × 4 squares or rolls
FIGURE 183-3. Alternative positioning of the patient.
CHAPTER 183: Temporomandibular Joint Dislocation Reduction
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FIGURE 183-4. Anesthesia of the temporomandibular joint. Insert the needle 2.5 cm anterior to the tragus of the auricle and just above the mandibular condyle.
FIGURE 183-5. Proper thumb and hand placement for the reduction of an anteriorly dislocated mandible. Apply downward pressure with the thumbs (1) followed by posteriorly directed pressure (2) to reduce the dislocation.
analgesics, sedatives, and/or muscle relaxants. Procedural analgesia and sedation may be required to overcome the patient’s pain and masticatory muscle spasm. This is especially true to relax the muscles of mastication and allow reduction if the mandible has been dislocated for more than 6 to 8 hours. Refer to Chapter 129 for the complete details regarding procedural analgesia and sedation. An alternative, or adjunct, to the administration of parenteral medications is to inject local anesthetic solution into the TMJ space (Figure 183-4). This injection is simple, quick, and relieves significant discomfort. Locate the depression 2.5 cm anterior to the tragus of the pinna and just above the head (condyle) of the mandible. This is the location of the TMJ space. Clean the skin of any dirt and debris. Apply povidone iodine or chlorhexidine solution to the skin over the TMJ space and allow it to dry. Insert a 25 gauge needle perpendicular to the skin and directed medially. Advance the needle 0.5 cm and into the TMJ space. Inject 1 mL of local anesthetic solution without epinephrine. Inject the contralateral TMJ space if the dislocation is bilateral. Consider injecting the contralateral TMJ space in a unilateral TMJ dislocation. The patient may experience pain in their contralateral TMJ from muscle spasm due to the increased pressure on it from the dislocation.
mandibular ridge immediately posterior to the molars. Wrap the index, middle, ring, and little fingers below the mandible, with the index fingers behind the angles of the mandible (Figure 183-5). Slowly apply downward and backward pressure to allow the muscles of mastication to stretch and overcome the muscle spasm (Figure 183-5). The downward pressure releases the mandibular condyle from the articular eminence of the temporal bone. Instruct the patient to further open their jaw to accentuate the deformity. This may disengage the impacted mandibular condyle from the anterior articular eminence of the TMJ. The masseter muscle will cause a rapid and sudden closing of the patient’s jaw when the condyle of the mandible snaps back and over the articular eminence.8
TECHNIQUE The actual reduction requires no specialized equipment beyond nonsterile gloves and gauze 4 × 4 squares. Position the patient as mentioned previously. Apply gloves and then wrap several layers of gauze around each thumb. The gauze squares on the thumbs are to prevent possible lacerations to the Emergency Physicians’ thumbs when the mandible reduces. This technique is the most commonly used method to reduce an anterior TMJ dislocation. Stand or sit in front of the patient (Figure 183-3). Place both thumbs into the patient’s mouth and onto the most posterior molars of the mandible bilaterally (Figure 183-5). Alternatively, the thumbs can be placed on the
ALTERNATIVE TECHNIQUES Numerous alternative techniques have been developed to reduce a TMJ dislocation. One technique is to place the thumbs on the buccal aspect of the molars. This avoids the potential injury to the thumbs when the mandible relocates. This method limits the force placed upon the mandible and may not result in a reduction. Another technique requires the physician to stand behind the patient and place downward and backward pressure on the lower molars (Figure 183-6). Inducing a gag reflex with a tongue depressor to relax the spasming muscles and free the condyle so it snaps back into anatomical position has been used to successfully reduce an anterior TMJ dislocation.9 Placing both thumbs on the occlusal surface of the molars on the dislocated side may allow additional pressure to reduce the dislocation that is not reduced using the traditional method.10 A final method to reduce an anterior TMJ dislocation is the wrist pivot method (Figure 183-7). Wrap the index and middle fingers of both hands with gauze. Place both thumbs under the patients’ chin and the wrapped fingers of both hands on the patients’ premolars and molars (Figure 183-7). Apply upward pressure with the thumbs while simultaneously applying downward pressure on the mandible with the fingers to unlock the mandible and reduce the dislocation.
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FIGURE 183-7. The wrist pivot method to reduce an anterior TMJ dislocation. FIGURE 183-6. An alternative method to reduce an anterior TMJ dislocation. The patient is supine. Downward and backward pressure is applied on the molars to reduce the dislocation.
COMPLICATIONS ASSESSMENT The patient should be able to open and close their mandible without any difficulty after a successful reduction. Postreduction radiographs are not necessary unless a fracture was present or suspected on prereduction radiographs.
AFTERCARE Refer the patient to an Oral Surgeon or Otolaryngologist within 24 to 48 hours.11 Chronic or recurrent dislocations may require surgical fixation, intermaxillary wiring, surgical alteration of the articular eminence (e.g., eminectomy or eminoplasty), sclerosing of the TMJ, or the injection of botulinum toxin into the lateral pterygoid muscles.12 Instruct the patient to avoid excessive jaw opening (over 2 cm), to avoid “gummy” foods and hard foods, and to begin a soft diet to avoid excessive strain on the TMJ. Instruct the patient to support their mandible with their hand when yawning so that it does not open widely and dislocate. Nonsteroidal antiinflammatory drugs will provide adequate analgesia, if needed at all. The application of warm compresses to the TMJ may provide additional pain relief. A Barton’s bandage can be applied around the head to keep the mandibular condyle in its fossa and minimize mandible opening. This bandage is often applied for 2 weeks in patients with chronic dislocations or acute recurrences. Only apply a Barton’s bandage in consultation with an Oral Surgeon or Otolaryngologist. Patients often do not like this bandage, are noncompliant, and remove it before follow-up.
Complications of the initial injury include fractures, intrusion of the mandibular condyle into the external auditory canal (posterior dislocation) or basal skull (superior dislocation), cerebral contusions, facial nerve injuries, and middle or inner ear injuries with hearing and balance impairments. Recurrent dislocations are possible in the future after the mandible has been dislocated once. The reduction technique is rarely associated with complications. Significant pain after a successful reduction may signify a fracture or articular cartilage avulsion. Fractures are rarely iatrogenic. They are often present on initial radiographs but not identified until retrospectively examined. A fracture may be displaced during the reduction. The Emergency Physician’s thumbs can be crushed and/or lacerated by the patient’s teeth. Closed reduction may be unsuccessful. The patient will require reduction under general anesthesia. This is particularly true of chronic dislocations, dislocations for longer than 12 hours, and recurrent dislocations. An avulsed articular cartilage or articular disc may be interposed and prevent closed reduction.
SUMMARY Uncomplicated anterior mandible dislocations can be managed with basic anesthesia and sedation techniques. A gentle and progressive reduction will allow the mandibular condyle to relocate into the TMJ space without significant complications. Dislocations that are complicated by fractures, overlying skin damage, nonanterior in location, or have associated neurological injuries require an emergent consultation and reduction by an Oral Surgeon or an Otolaryngologist.
SECTION
Podiatric Procedures
184
Ingrown Toenail Management Jeff Schaider
INTRODUCTION An ingrown toenail (onychocryptosis) is a common affliction that can occur in any toe. It most commonly afflicts the great toe, occurring when the lateral edge of the nail plate penetrates the soft tissue of the lateral nail fold. There are three stages of ingrown toenails. Stage I includes erythema, slight edema, and pain when pressure is applied to the lateral nail fold. Stage II includes the stage I findings plus signs of infection and a purulent drainage. Stage III is a magnification of the two previous stages with the addition of granulation tissue formation and lateral nail fold hypertrophy. Most ingrown toenails can be definitively managed in the Emergency Department by the Emergency Physician.
ANATOMY AND PATHOPHYSIOLOGY The toenail usually does not grow into the soft tissue. Instead, the soft tissue overgrows and obliterates the nail sulcus in response to external pressure and irritation.1–5 The toenail itself is usually normal, although some older patients may have incurved nails. The causes of an ingrown toenail are multiple and include trimming the toenails too short, using sharp tools to clean the toenail gutters, wearing improperly fitted (too tight) shoes, rotated digits, and bony deformities. Improper toenail trimming can result in a small nail spike on the lateral aspect of the toenail (Figure 184-1). As the toenail continues to grow, the spike will irritate the soft tissue causing the end result of chronic inflammation and an infection.
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INDICATIONS Warm soaks, oral antistaphylococcal antibiotics, and shoes with an adequate toe box may be curative in mild cases (stages I and II). Elevate and maintain the nail edge above the soft tissues or trim the edge of the nail (Figure 184-2). More severe cases (stage III) require partial toenail removal. Have a lower threshold for toenail removal in diabetic patients to prevent a more severe infection from forming. Other indications for removal of an ingrown toenail include chronic or recurring ingrown toenails, failure of conservative therapy, fungal infections of the toenail, and severe pain.
CONTRAINDICATIONS The only relative contraindication to toenail removal is a decreased vascular supply to the toe. Trim the toenail edge if possible and minimize any injury to the adjacent soft tissues. These patients require an evaluation by a Podiatrist and a Vascular Surgeon to minimize future complications.
EQUIPMENT General Supplies • Povidone iodine or chlorhexidine solution • Sterile drapes • Sterile gloves • Curved hemostat • Freer or another periosteal elevator • Cotton • Scissors or nail splitter • Tourniquet or sterile Penrose drain • Curette • Topical antibacterial ointment • 4 × 4 gauze squares • Tape, 1 inch wide Chemical Matrix Ablation • Above listed general supplies • Cotton-tipped applicators • 89% phenol solution • 70% isopropyl alcohol solution • Silver nitrate matchsticks
FIGURE 184-1. An ingrown toenail. Note the nail spicule and the overgrowth of the adjacent soft tissues.
Surgical Matrix Excision • Above listed general supplies • #15 scalpel blade on a handle • Needle driver • 5-0 nylon suture 1169
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FIGURE 184-2. Management of stage I and II ingrown toenails. A. Trimming the lateral nail edge. B. Elevation of the lateral nail edge.
Nail Matrix Cauterization • Above listed general supplies • Electrocautery unit, disposable
PATIENT PREPARATION Explain the risks, benefits, complications, and aftercare of the procedure to the patient and/or their representative. Obtain an informed consent for the procedure. Place the patient supine on a gurney or procedure table. Flex the patient’s hip and knee so that the plantar surface of their foot is flat against the gurney. An overhead light source is essential to provide appropriate illumination. Perform a digit block using aseptic technique. Refer to Chapter 126 regarding the details of digital anesthesia. While rare, an occasional nervous or uncooperative patient may require an intravenous anxiolytic or even procedural sedation prior to the digital anesthesia. The young child will require physical restraint with a sheet or commercial device (e.g., Papoose board) and procedural sedation. Apply povidone iodine or chlorhexidine solution over the involved toe and allow it to dry. Apply a sterile drape to delineate a sterile field.
TECHNIQUES Manage early ingrown toenails (stages I and II) with conservative therapy. Remove the medial or lateral one-quarter of the toenail along with the germinal matrix at the base of the toenail for stage III ingrown toenails. The entire nail may be removed if both sides are ingrown. It may be necessary to prevent any new nail growth in the area once the nail has been removed. Three options include chemical ablation of the matrix, surgical excision of the matrix, and electrocautery of the nail matrix. The treatment of the pediatric patient is no different than the adult patient.
TOENAIL ELEVATION AND TRIMMING Ingrown toenails in the first two stages can be trimmed or elevated to relieve the patient’s symptoms (Figure 184-2). Trim the distal edge of the nail plate to remove the ingrown portion (Figure 184-2A). Remove the distal one-third to one-half of the nail plate. Smooth the nail plate edge so that it will grow out freely. Remove any debris along the lateral nail fold (paronychia) or nailbed. An alternative is to elevate the edge of the nail plate (Figure 184-2B). Insert the jaws of a hemostat so that one is above and the other is below the ingrown nail edge. Clamp the jaws of the hemostat onto the nail plate. Slowly rotate the hemostat to elevate the edge of the nail plate above the adjacent soft tissues (Figure 184-2B). Insert a wad of cotton under the nail edge to maintain it above the
adjacent soft tissues. Release the hemostat. Teach the patient and/or their representative this technique so that they can replace the cotton wad daily until the nail plate grows out and past the soft tissues. The main disadvantages of this technique are that the patient or their representative must elevate the nail edge and replace the cotton daily as well as maintain the nail plate elevation for 3 to 6 weeks. This can be quite a challenge, if it is even possible, in the young child.
TOENAIL REMOVAL Apply a tourniquet along the base of the afflicted toe (Figure 184-3A). The tourniquet may be a commercially available product for the digits or a Penrose drain. Refer to Chapter 104 for several examples of digital tourniquets. Separate the nail from the underlying nail bed. Grasp and stabilize the toe with the nondominant hand. If available, use a Freer periosteal elevator to lift the soft tissue off the lateral and proximal toenail. The elevator can also be used to separate the nail plate from the underlying nail bed, but this is optional. Insert one jaw of a curved hemostat under the distal toenail margin and along the medial or lateral side of the nail plate, depending upon which side is ingrown (Figure 184-3B). Advance the hemostat until the jaw is at the proximal corner of the involved side of the ingrown nail (Figure 184-3C). Grasp the nail by clamping the jaws of the curved hemostat on the toenail. Dislodge the ingrown nail from the skin, the nail bed, and the nail matrix by rotating the hemostat away from the ingrown portion (Figure 184-3D). Continue to rotate the hemostat until the entire ingrown portion of the nail is separated from the skin, the nail bed, and the nail matrix. A large and complete portion of the underlying toenail will emerge from under the skin fold (Figure 184-3E). The nail plate might have broken and a significant piece may still be under the inflamed skin border if only a small amount of the nail is visible after rotating the hemostat. Expose this area and use the curved hemostat to remove any remaining nail plate. Cut away the ingrown portion of the toenail, from distal to proximal, with a heavy scissors or nail splitter (Figure 184-3F). Make sure that the points of the scissors or nail splitter are facing upward to prevent injury to the nail bed. The granulation tissue overlying the nail bed must be removed to prevent another ingrown toenail (Figure 184-3G). Trim the granulation tissue using a #15 scalpel blade or a curette (Figure 184-3H). Remove the tourniquet and control any bleeding. Some Emergency Physicians prefer to perform the abovedescribed procedural steps in a slightly different order. Apply a tourniquet along the base of the afflicted toe. Grasp and stabilize the toe with the nondominant hand. If available, use a Freer periosteal elevator to lift the soft tissue off the lateral and proximal
CHAPTER 184: Ingrown Toenail Management
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FIGURE 184-3. Ingrown toenail removal. A. Placement of a tourniquet. B. Place one jaw of the hemostat above the nail plate and one jaw beneath the nail plate. C. Advance the hemostat toward the base of the nail plate. D. Rotate the hemostat to elevate the edge of the toenail. Be sure to elevate and expose the proximal nail segment at the base of the nail in the region of the nail matrix. E. Determine where to cut the nail plate. F. Cut the nail plate with a heavy scissors or a nail splitter. G. The lateral one-fourth of the nail plate has been removed. H. The granulation tissue has been trimmed away.
toenail. The elevator can also be used to separate the nail plate from the underlying nail bed, but this is optional. Cut away the ingrown portion of the toenail, from distal to proximal, with a heavy scissors or nail splitter. Make sure that the points of the scissors or nail splitter are facing upward to prevent injury to the nail bed. Insert one jaw of a curved hemostat under the distal toenail margin and along the medial or lateral side of the nail plate, depending upon which side is ingrown. Advance the hemostat until the jaw is at the proximal corner of the involved side of the ingrown nail. Grasp the nail by clamping the jaws of the curved hemostat on the toenail. Dislodge the ingrown nail from the skin, the nail bed, and the nail matrix by rotating the hemostat away from the ingrown portion. Continue to rotate the hemostat until the entire ingrown portion of the nail is separated from the skin, the nail bed, and the nail matrix. A large and complete portion of the underlying toenail will emerge from under the skin fold. The nail plate might have broken and a significant piece may still be under the inflamed skin border if only a small amount of the nail is visible after rotating the hemostat. Expose this area and use the curved hemostat to remove any remaining nail plate. Remove the granulation tissue overlying the nail bed to prevent another ingrown toenail using a #15 scalpel blade or a curette. Remove the tourniquet and control any bleeding.
field of any blood and fluid. Dip a cotton-tipped applicator in a phenol solution. Avoid excessive saturation of the swab. Introduce the swab between the roof and the root matrix (i.e., under the eponychium) of the removed nail section (Figure 184-4). Rotate the cotton-tipped applicator slowly for 30 seconds (20 seconds for children) and then remove it. Repeat the phenol application two additional times using a fresh phenol-soaked cotton-tipped applicator.
CHEMICAL NAIL MATRIX ABLATION Chemical ablation of the nail matrix with phenol has several advantages.6,7 The procedure is easy, quick, and simple to perform. No special equipment is required. The use of an incision or electrocautery, and their associated complications, is avoided. Chemical ablation of the matrix with phenol is the author’s preferred method. Remove any obvious remaining nail matrix and nail bed with a blunt instrument such as a curette. Completely dry the
FIGURE 184-4. Chemical nail matrix ablation.
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FIGURE 184-5. Surgical nail matrix ablation. A. An incision in the eponychium to expose the matrix. B. Removal of the matrix. The pink shading represents the areas of tissue to be removed.
Do not allow the phenol to contact normal skin. Immediately wipe off any phenol that contacts the skin. The phenol will turn the tissue pale or gray. Dip a cotton-tipped applicator in isopropyl alcohol. Swab the area in similar fashion as the phenol swab. The isopropyl alcohol neutralizes the necrotizing effect of the phenol.6–8 An alternative to phenol is silver nitrate. The preferred technique is a phenol matrixectomy. Silver nitrate may be used if phenol is not available. The main disadvantage of silver nitrate is that it turns the tissues black. Insert the silver nitrate matchstick under the eponychium (Figure 184-4). Roll the matchstick around for 5 to 10 seconds to ablate the matrix.
SURGICAL NAIL MATRIX ABLATION Surgical excision of the toenail matrix requires more time and experience than chemical ablation.4 This technique is usually reserved for the Podiatrist or the Orthopedic Surgeon. An experienced Emergency Physician can easily perform this technique in the Emergency Department. Expose the nail matrix by retracting the adjacent overlying skin. Make an oblique proximal incision from the proximal corner of the nail if necessary to fully expose the nail matrix in the ingrown area (Figure 184-5A). Make an incision with a #15 scalpel blade to separate the nail matrix to be removed from the remaining nail and matrix (Figure 184-5B). Grasp the corner of the matrix with a hemostat. Use the scalpel blade to separate the matrix from the underlying tissues. Remove the nail matrix. Do not forget to remove the dorsal and deep matrix that envelops the base of the toenail under the skin fold. Remove any remaining nail matrix and nail bed with a curette. Close the skin incision with 5-0 nylon suture.
painful. Instruct the patient to elevate the foot for the first 2 to 3 days to prevent bleeding and edema. Large shoes, sandals, or cast shoes are best used in the immediate postprocedure days. The use of oral antibiotics is restricted for patients who are immunocompromised, have an associated cellulitis, or whose vascular supply to the toe is decreased. Prescribe nonsteroidal anti-inflammatory drugs supplemented with narcotic analgesics as needed for pain control. Instruct the patient to return to the Emergency Department immediately if they experience increased pain, develop a fever, a purulent discharge, or notice increased redness of the toe or foot. Demonstrate the proper method to trim toenails (Figure 184-6). Chemical ablation of the matrix with phenol induces a chemical burn. The patient may experience a serous drainage for a few days up to 2 weeks.1 The use of nonsteroidal anti-inflammatory drugs can limit the duration and the amount of drainage.1 Instruct the patient to soak the foot in warm water three times a day for 10 to 15 minutes each time. Apply a topical antibiotic ointment after each soak. Prolonged drainage may be due to a superficial infection and requires evaluation.
COMPLICATIONS The most common complication is the persistence of toenail horns or spikes due to incomplete ablation of the nail and matrix. These can be managed with nail trimming if mild or en bloc excision of the area if severe. Ensure that the portion of the nail is completely removed and that no fragments remain under the nail folds. Use care to not lacerate the nail bed when elevating or cutting the nail plate. Lacerations of the nail bed can bleed significantly, cause chronic pain once healed, and result in a deformed
ELECTROCAUTERY NAIL MATRIX ABLATION Electrocauterization of the nail matrix is rapidly performed but requires access to an electrocautery instrument. Apply electrocautery between the roof and the root matrix of the removed nail section to destroy the matrix in this area. Avoid excessive burning of the surrounding tissues. This technique can cause significant damage to normal tissue and should be reserved for the Podiatrist or the Orthopedic Surgeon.
AFTERCARE Apply a topical antibiotic ointment and a small compressive gauze dressing over the toe. The patient requires follow-up in 24 to 48 hours for a dressing change and evaluation of the wound. Saturate the dressing with saline or sterile water to make the removal process less
FIGURE 184-6. The technique of toenail trimming. A. Correct. B. Incorrect.
CHAPTER 185: Toe Fracture Management
nail. Repair any nail bed lacerations. Refer to Chapter 104 for a complete discussion regarding nail bed repair. Phenol will deteriorate if it is exposed to air or light. Store the phenol solution in a cool, dark place. Replace the solution frequently. The field must be dry before applying phenol. Phenol mixed with blood results in an alteration of the pH of the phenol, decreasing its effectiveness, and turning the tissues black. The ingrown toenail will recur if the phenol is old or exposed to light before it is used, if the phenol is not properly applied, or if fragments of the toenail or matrix remain. The patient may experience a chemical burn if too much phenol is applied or it is not neutralized with isopropyl alcohol.
SUMMARY An ingrown toenail can be managed easily, quickly, and definitively in the Emergency Department. Perform a partial toenail removal on patients with clinical stage III toenails characterized by pain, overgrowth of inflamed and infected tissue, and drainage. Remove the lateral or medial one-quarter of the nail. Apply phenol solution to the nail matrix to prevent further growth of the nail and a recurrence.
185
Toe Fracture Management George Chiampas and Steve Zahn
INTRODUCTION Toe fractures result from a direct blow (from an object falling on an unprotected toe) or a “stubbing” injury.1 The incidence of toe fractures has been estimated at 140 cases per 100,000 people per year.2 The significance of toe fractures depends upon which digit is
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affected. Most important is the great toe, as it is the main propulsive segment of the forefoot. Many patients do not present to the Emergency Department as they consider the injury trivial. Those who do present often do so because of severe pain and/or a large subungual hematoma. Toe fractures are common injuries that rarely require surgical treatment. They may be completely and definitively managed in the Emergency Department. Most toe fractures require only a properly placed splint. An intraarticular fracture with severe displacement of the great toe may require open reduction and internal fixation to prevent deformity and arthritis in the joint. Complications of a toe fracture include damage to the articular cartilage, hypermobility of fracture segments, malposition, and malunion.
ANATOMY AND PATHOPHYSIOLOGY The foot can be anatomically divided into the forefoot, the midfoot, and the hindfoot (Figure 185-1). The forefoot is composed of the metatarsals and their respective phalanges. Sesamoid bones often lie along the plantar surface of the metatarsal heads. The sesamoid bones of the great toe lie in a groove on the plantar surface of the metatarsal head and within the tendon of its respective flexor hallucis brevis muscle belly. Each toe has two pairs of digital nerves that course along the superior and inferior aspects of the digit. The digital artery and vein accompany the nerve. The great toe often receives superficial cutaneous nerves along its dorsal surface. Anteroposterior and oblique radiographic views will demonstrate most fractures. Lateral views may be necessary to identify phalangeal fractures of the great toe. Obtain the lateral projection with toes 2 through 5 passively dorsiflexed to avoid overlap. An alternative method to achieve adequate radiographic views of the great toe in the lateral projection is to insert dental X-ray film between the first and second toes and direct the X-ray beam laterally.3
FIGURE 185-1. The bony anatomy of the foot.
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INDICATIONS The indications for simple splinting of toe fractures are to relieve pain and allow for healing. The management of closed fractures depends upon the digit involved. Manage nondisplaced phalangeal fractures of the great toe with buddy taping to the adjacent normal toe as a splint. Mildly displaced phalangeal fractures of the great toe can be reduced using local anesthesia, gentle traction, and buddy taping. Manage nondisplaced phalangeal fractures of toes 2 through 5 with buddy taping. Mildly displaced phalangeal fractures of toes 2 through 5 can be reduced using local anesthesia, gentle traction, and buddy taping. Exact anatomic reduction of toes 2 through 5 is not a concern as long as the general alignment of the toe is satisfactory.4
CONTRAINDICATIONS Consult an Orthopedic Surgeon or Podiatrist for open fractures, extensive crush injuries to the forefoot, injuries with the potential to develop a compartment syndrome, intraarticular fractures, or severely displaced toe fractures (especially of the great toe). The incidence of arthritis and malunion is quite high with these injuries. Fractures of multiple toes on one foot cannot be treated with buddy taping.
EQUIPMENT • • • • • • • • • •
Povidone iodine or chlorhexidine solution Local anesthetic solution without epinephrine 25 or 27 gauge needle 5 mL syringe 2 × 2 gauze squares or a soft corn pad Finger trap, optional Bunion pad Metatarsal bar or wooden tongue depressors Permeable tape, ½ inch wide Fluoroscopy unit, optional
The use of a fluoroscopy unit, if available, will make the reduction technique much easier and quicker. It allows for the immediate evaluation of the reduction, multiple reduction attempts without the waiting time to obtain plain radiographs after each reduction attempt, and the reduction to be completed and splinted before the anesthesia wears off.
PATIENT PREPARATION Explain the risks, benefits, and potential complications of the procedure to the patient and/or their representative. Obtain a signed informed consent for the procedure. Obtain plain radiographs or a fluoroscopic image to assess the severity of the injury. Place the patient sitting upright so that the affected foot is suspended above the floor in order to allow adequate space for manipulation and splinting of the toe. An alternative is to place the patient supine with their hip and knee flexed, so that the sole of the foot is flat against the gurney. If a subungual hematoma is present, it should be drained to relieve the pressure on the nail bed and improve patient comfort. Refer to Chapter 102 for the complete details regarding the management of a subungual hematoma. The use of anesthesia is Emergency Physician and patient dependent. Buddy taping of nondisplaced fractures of toes 1 through 5 or minimally displaced fractures of toes 2 through 5 requires no anesthesia. Consider performing a digital block if the patient is significantly tender and a displaced fracture must be reduced. Clean the web spaces of the affected toe of any dirt or debris. Apply povidone iodine or chlorhexidine solution to the web space and surrounding skin. Allow the solution to dry. Arm a 5 mL syringe containing local anesthetic solution (e.g., lidocaine or bupivacaine) without epinephrine with a 25 or 27 gauge needle. Insert the needle into the dorsal surface of the web space. Aim the needle 45° downward and toward the posterior aspect of the phalanx (Figure 185-2A). Advance the needle while injecting 1 to 2 mL of local anesthetic solution. Do not puncture the plantar surface of the toe. The local anesthetic solution will easily inject into the areolar tissue of the web space. Withdraw the needle. Shift the needle so that it is aimed along the dorsal surface of the toe (Figure 185-2B). Advance the needle while injecting 1 to 2 mL
FIGURE 185-2. Digital block of the toe. A. Needle position and direction for infiltration of the lateral surface. B. Needle position and direction for infiltration of the dorsal surface.
CHAPTER 185: Toe Fracture Management
of local anesthetic solution over the dorsal surface. Completely withdraw the needle. Inject local anesthetic solution into the contralateral side of the affected toe in the same way as in the first web space. Allow 5 to 10 minutes for the block to take effect. Reassess the patient to determine whether the block was successful. An additional injection along the plantar surface of the toe may be required to provide total anesthesia, especially of the great toe. Refer to Chapter 126 for additional details regarding digital anesthesia. An alternative is to perform a hematoma block by injecting local anesthetic solution directly into the fracture site. Clean and prepare the skin. Insert the needle over the fracture site. Advance the needle until it enters the fracture. Aspirate a small amount of blood to confirm that the tip of the needle is properly positioned within the fracture. Inject 2 to 3 mL of local anesthetic solution into the hematoma. Allow 5 to 10 minutes for the local anesthetic to take effect before proceeding. Refer to Chapter 125 for a more complete discussion of a hematoma block.
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FIGURE 185-4. Manual fracture reduction.
TECHNIQUES FRACTURE REDUCTION Closed reduction can be achieved with the use of a finger trap or straightforward axial traction. Place the anesthetized affected toe in the finger trap (Figure 185-3). Elevate and suspend the foot by the affected toe in the finger trap (Figure 185-3). Allow the weight of the leg to slowly distract the fracture site. Reduce the fracture (Figure 185-4). Grasp the forefoot near the base of the affected toe or fractured phalanx with the nondominant index finger and thumb. Grasp the distal aspect of the fractured phalanx with the
dominant index finger and thumb. Apply distally directed inline traction with the dominant hand and simultaneous countertraction with the nondominant hand to distract the fracture site. Remove the toe from the finger trap. Obtain a radiograph or fluoroscopic image to confirm the reduction. Buddy tape the toe to the adjacent toe as described below. The alternative is to reduce the fracture manually without the use of a finger trap (Figure 185-4). Grasp the forefoot near the base of the affected toe or fractured phalanx with the nondominant index finger and thumb. Grasp the distal aspect of the fractured phalanx with the dominant index finger and thumb. Apply distally directed inline traction with the dominant hand and simultaneous countertraction with the nondominant hand to distract the fracture site. Reduce the fracture. Obtain a radiograph or fluoroscopic image to confirm the reduction. Buddy tape the toe to the adjacent toe as described below.
BUDDY TAPING Buddy tape the toe after the reduction (Figure 185-5). Place a piece of folded 2 × 2 gauze or a corn pad between the fractured toe and its neighboring toe (Figure 185-5A). The gauze or corn pad will prevent maceration and pressure necrosis of the skin. Tape the toes together (Figure 185-5B).
ASSESSMENT Reassess the toe’s perfusion by checking the capillary refill time after any attempt at reduction. Obtain a postreduction radiograph or fluoroscopic image to verify proper alignment. Mild to moderate displacement in phalangeal fractures of toes 2 through 5 is quite acceptable as long as the toes are not rubbing together. Repeat the reduction process as necessary to reduce the fracture. Consult an Orthopedic Surgeon or Podiatrist if the fracture cannot be adequately reduced.
AFTERCARE
FIGURE 185-3. Use of the finger trap to aid fracture reduction.
All toe fractures are persistently painful. They require analgesia and splinting for 2 to 3 weeks. Prescribing nonsteroidal anti-inflammatory drugs (NSAIDs) supplemented with narcotic analgesics has been the standard of care. New research may shift future management from the use of NSAIDs as these medications can delay fracture healing.5 The patient can apply ice packs for 10 to 15 minutes every 3 hours to help decrease pain and swelling.
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FIGURE 185-5. Buddy taping the fractured toe. A. Place gauze or a corn pad between the fractured toe and an adjacent toe. B. Tape the toes together.
Provide the patient with a hard-soled shoe, wooden-soled shoe, or Reese orthopedic shoe. It is felt that dorsiflexion of the forefoot in walking causes the most pain in toe fractures.3 The use of these shoes, as opposed to the patient’s own shoes, minimizes pain with walking. An alternative to the orthopedic shoe is to place a metatarsal bar for patient comfort.6 Use a commercially available unit or make a metatarsal bar by taping wooden tongue depressors together (Figure 185-6).3 Obtain four tongue depressors and cut one in half (Figure 185-6A). Place two tongue depressors side by side (Figure 185-6B). Place the third tongue depressor to cover the seam of the adjacent tongue depressors (Figure 185-6B). Tape the tongue depressors together to form the longitudinal support (Figure 185-6C). Apply the cut tongue depressor to form the
transverse support (Figure 185-6D). Tape the transverse support to the longitudinal support (Figure 185-6E). Apply the metatarsal bar to the sole of the patient’s shoe (Figure 185-7). Additional support and pain control can be achieved by immobilizing the foot in a short leg walking cast with a toe plate for no more than 1 to 2 weeks if the patient complains of persistent pain.4 Instruct the patient to continue weight bearing as tolerated and, when not walking, to elevate the foot above the level of their heart to minimize swelling. Teach the patient how to re-apply the buddy taping splint, as it must be changed every 2 to 3 days for up to 6 weeks. All patients with great toe fractures should follow-up with an Orthopedic Surgeon or Podiatrist within 48 hours for a reevaluation.
COMPLICATIONS Long-term sequelae from toe fractures are rare. Persistent angulation at the fracture site with a malunion may result in a “sore area” on the plantar surface of the toe. Refer the patient to an Orthopedic Surgeon or Podiatrist if such areas remain symptomatic and functionally disabling. A simple surgery can correct the problem. Any fractures involving the joint space will result in some degree of arthritis. Warn the patient of this possible complication before they are discharged.
FIGURE 185-6. Fabricating a metatarsal bar from tongue depressors. A. Lay out four tongue depressors, one of which is cut in half. B. Place two tongue depressors side by side. Place the third tongue depressor to cover the seam between the first two. C. Tape the tongue depressors together to form the longitudinal support. D. Apply the cut tongue depressor to form the transverse support. E. Tape the transverse support to the longitudinal support.
FIGURE 185-7. Application of the metatarsal bar to the patient’s shoe. A. Inferior view. B. Lateral view.
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Few complications are associated with the management of toe fractures. Incomplete reduction can result in an angulated toe. Persistent angulation can result in the toe pushing against adjacent toes, skin irritation, and possible skin ulceration. Always place a pad between the toes before buddy taping to prevent irritation, pressure necrosis, ulceration, and maceration of the skin.
SUMMARY Toe fractures are commonly seen in the Emergency Department. They may cause the patient significant pain and discomfort. Simple conservative management with the use of buddy taping and appropriate footwear helps the fracture heal in 3 to 6 weeks. Open or closed surgical reduction of phalangeal fractures may be required to achieve proper reduction. Intraarticular or severely displaced toe fractures, especially those of the great toe, should be referred to an Orthopedic Surgeon or Podiatrist. Most toe fractures can be satisfactorily and definitively managed by the Emergency Physician with a minimum of complications.
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Neuroma Management Eric R. Snoey and Stephen Miller
INTRODUCTION Morton’s neuroma, also referred to as an interdigital neuroma, is one of the most common painful disorders of the forefoot. It was first described in 1845 by Dulacher. It is named after Thomas Morton, who presented a case series of patients afflicted with this disorder in 1876. Patients with an established Morton’s neuroma are usually cared for by a Podiatrist or an Orthopedist. They may present to the Emergency Department with a previously undiagnosed neuroma or with a painful exacerbation of a previously diagnosed neuroma. The term neuroma is actually a misnomer. Histologic investigation does not reveal the typical proliferation of axons found in true neuromas. Instead, there is a fibrosis and thickening of the perineural tissue with corresponding degeneration of the underlying nerve in a Morton’s neuroma.1 This most commonly affects the third plantar common digital nerve located in the third interspace, between the third and fourth metatarsal heads. It may also occur less commonly in the second interspace, between the second and third metatarsals. A neuroma is rarely seen in the first or fourth interspaces, between the first and second or the fourth and fifth metatarsals, respectively. Morton’s neuroma most commonly affects women between their fourth and sixth decades.2 It is especially common in those who wear high-heeled shoes, poor fitting shoes, worn shoes, shoes with poor or no padding, or shoes that are narrow at the forefoot. Persons with pronated or pes cavus feet are similarly at risk.3 Neuromas do not usually become symptomatic until their transverse diameter reaches more than 5 mm.4
FIGURE 186-1. Morton’s neuroma most commonly occurs in the third intermetatarsal space beneath the transverse metacarpal ligament.
up of branches from both the medial and lateral plantar nerves (Figure 186-1). Most commonly affected is the third interdigital nerve. It is the largest of the interdigital nerves and may explain the increased frequency of neuroma formation in this location. Morton and others postulated that the increased mobility of the fourth and fifth metatarsal heads relative to the more fixed medial portion of the foot results in disproportionate trauma to the third interdigital nerve. These mechanical factors, combined with the impingement and stretching from a tight transverse intermetatarsal ligament, result in repetitive microtrauma. Histologic evaluation reveals perineural fibroma formation consistent with compression-induced trauma.2 Injury begins with edema of the endoneurium, followed by fibrosis beneath the perineurium, axonal degeneration, and finally neuronal necrosis. Some authors believe that a more significant contributor to neuroma formation is enlargement of the interphalangeal component of the intermetatarsophalangeal bursa, leading to microvascular trauma.5 Movements of the bursa result in minor compressive effects on the adjacent digital arteries, leading to ischemia of local neural tissue.
ANATOMY AND PATHOPHYSIOLOGY Neuromas form just proximal to the bifurcation of the plantar common digital nerves (Figure 186-1) and below the deep transverse intermetatarsal ligament (Figure 186-2). The deep transverse intermetatarsal ligament connects the metatarsal heads on the plantar aspect of the foot (Figure 186-2). The neuroma is made
FIGURE 186-2. Anatomy of the forefoot. Cross section through the distal metatarsals.
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SECTION 15: Podiatric Procedures
The diagnosis of a Morton’s neuroma is usually made clinically, based upon classic historical features and physical examination findings.1 The pain of a neuroma usually begins intermittently, becoming more frequent with time and eventually constant. The patient may complain of pain, burning, electric shocks, or tingling over the involved intermetatarsal space. Attacks typically occur suddenly after a period of walking, running, or standing.5 Some patients may complain of pain disturbing their sleep.5 Hyperesthesia or hypoesthesia in the involved toes and web space is common. Patients often complain of the unilateral feeling of “walking on a lump.” Symptoms are aggravated by walking, particularly in narrow shoes, and relieved by rest and shoe removal. Physical examination localizes the pain to the involved interspace with minimal involvement of the adjacent metatarsal heads. Moderate pressure applied proximally in the affected web space reproduces the pain. A small mass, representing the neuroma, can be palpated in approximately one-third of the cases. A positive Mulder’s sign is diagnostic.6 This is a click felt in the interspace with medial and lateral compression of the metatarsal heads during simultaneous palpation of the interspace (Figure 186-3). Radiographic imaging may be helpful in confirming the diagnosis and exploring alternative etiologies. Plain radiographs will not demonstrate a neuroma. They may reveal splaying of the involved toes when the neuroma is especially large or alternative diagnoses such as stress fractures or arthritis. Ultrasound represents the most efficient and effective imaging modality.2,7 An experienced operator may identify hypoechoic neuromas as small as 2.9 mm.8 Magnetic resonance imaging (MRI) is quite effective at identifying the presence of a neuroma, but cost and access issues make it a less practical choice, especially in the Emergency Department.1 Computed tomography (CT) may be useful if an MRI is contraindicated or not available. The sensitivity of CT scanning is less than that of MRI or ultrasound.2
INDICATIONS Injection of the presumed neuroma will provide significant relief to the patient and confirm a Morton’s neuroma as the etiology of the patient’s complaints. Injection is indicated after less invasive methods have failed.9,10 These include foot elevation and rest, nonsteroidal anti-inflammatory drugs, arch supports, orthoses, and changing footwear to prevent forefoot compression (i.e., low heels and wide toe boxes). Corticosteroid injections can provide partial or complete relief in up to 80% of patients.9,11
CONTRAINDICATIONS The primary contraindication to injection of a Morton’s neuroma is failure to make a correct initial diagnosis. The differential diagnosis for forefoot pain includes a wide variety of pathologies, many of which may closely mimic the presentation of a neuroma. Alternative diagnoses include tarsal tunnel syndrome, peripheral neuropathy, capsulitis, bursitis, rheumatoid arthritis, foreign bodies, avascular necrosis, stress fractures, and peripheral vascular insufficiency. A careful history and physical examination with discretionary use of imaging modalities will lead to a correct diagnosis. Some specialists believe injection therapy to be contraindicated in serious athletes.3 They propose that steroid injection may result in fat pad atrophy, degeneration of the volar plate, and degeneration of the collateral ligaments. A discussion of alternative therapies to injection therapy is provided later in this chapter.
EQUIPMENT • • • • • • • •
Sterile gloves Sterile drapes Povidone iodine or chlorhexidine solution 3 mL syringe 22 or 25 gauge needle 0.5% bupivacaine without epinephrine Injectable methylprednisolone or triamcinolone Sterile bandage
PATIENT PREPARATION Explain the risks, benefits, complications, and aftercare of the procedure to the patient and/or their representative. Place the patient supine on a gurney with their hip and knee flexed so that the sole of the affected foot is flat on the gurney. Clean the skin overlying the neuroma of any dirt and debris. Apply povidone iodine or chlorhexidine solution and allow it to dry. Apply sterile drapes to isolate a sterile field. Prepare the injection solution. Mix 1 mL of 0.5% bupivacaine without epinephrine in a 3 mL syringe with 10 mg of methylprednisolone or triamcinolone. Another local anesthetic agent, without epinephrine, may be used instead of bupivacaine. Long-acting local anesthetic agents are preferred as they provide the patient with longer pain relief after the injection.
TECHNIQUE
FIGURE 186-3. Examination for Mulder’s click. The thumb and forefinger of the examiner’s dominant hand are used to compress the interdigital space. The nondominant hand then performs medial and lateral compression of the metatarsal heads (arrows). A palpable click is diagnostic, while pain alone is suggestive of a neuroma.
Instruct the patient to moderately dorsiflex their toes to separate the metatarsal heads. Use a dorsal approach to the neuroma, as this is less painful than penetrating the sole with a needle. If the neuroma is palpable, insert the needle perpendicular into the skin overlying the neuroma. Advance the needle perpendicular to the skin and into the neuroma or into its fascial plane (Figure 186-4). Inject the affected interspace with 1 to 2 mL of the combination long-acting local anesthetic agent and steroid.
CHAPTER 186: Neuroma Management
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Two recent studies have described the injection of dilute alcohol into the site of the neuroma using ultrasound guidance. The effect is to sclerose and harden the perineural tissues. The injection is typically repeated every 1 to 2 weeks and on average 4 to 7 times, with treated patients experiencing a significant reduction in symptoms and neuroma size.14,15 Podiatrists and Orthopedists may offer more aggressive and definitive therapy when conservative measures fail. Surgical excision using a dorsal approach has success rates as high as 84% to 93%.16–18 The podiatry literature offers increasing support for endoscopic decompression of the deep transverse intermetatarsal ligament, thus leaving the nerve intact. The advantage is a shorter recovery time, which may make this especially desirable for athletes. No longterm results have been reported, but short-term results appear quite promising.3 Excision using a carbon dioxide laser is yet another treatment option that may allow for an even shorter recovery.7 FIGURE 186-4. Injection of the neuroma.
In the absence of a palpable neuroma, insert the needle approximately 1 to 2 cm proximal to the web space. Direct the needle into the facial space between the deep and superficial transverse metatarsal ligaments. Note that this space is deep to the metatarsal heads on the plantar aspect of the foot (Figure 186-2).
ALTERNATIVE TECHNIQUES Various types of conservative treatment can be initiated once a Morton’s neuroma is diagnosed. A wide range of success rates have been reported (20% to 80%) using a combination of injections with other conservative therapy including orthoses, metatarsal pads, shoes with wider toe boxes, and physical therapy.12,13 Orthoses are used to help control abnormal pronation, although some studies have shown this to be ineffective.13 Metatarsal pads serve to spread the metatarsal heads at the involved interspace and decrease compressive trauma (Figure 186-5). The types of physical therapy employed include massage, ultrasound, electrical stimulation, and whirlpool immersion. A trial of acetaminophen or nonsteroidal anti-inflammatory drugs may be helpful in the short term.
ASSESSMENT Allow 10 to 20 minutes for the local anesthetic agent to take full effect. The patient will experience a rapid resolution of symptoms if the injection is successful. The relief of pain confirms that the corticosteroid has been injected into the correct location, allowing it to work on the neuroma.
AFTERCARE Pain may be controlled with the use of acetaminophen or nonsteroidal anti-inflammatory drugs. Instruct the patient to wear flat shoes, shoes with flat and wide toe boxes, and to avoid shoes whose heel is elevated above the metatarsals (usually a heal no higher than 0.5 to 1.0 inches). The patient should avoid activities that place repeated pressure on the forefoot (e.g., bicycling, jogging, and sports). Apply a metatarsal pad to decrease compressive forces on the neuroma. Place the dome of the pad between the third and fourth metatarsals and just posterior to the metatarsal heads (Figure 186-5). Cold packs can be applied for 10 to 15 minutes every 3 hours to decrease inflammation and pain, especially after activities that aggravate the patient’s symptoms. Refer the patient to a Podiatrist or Orthopedic Surgeon for follow-up, additional injection therapy, orthoses, physical therapy, and possible surgical management.
COMPLICATIONS Complications associated with neuroma injection are exceedingly rare. They include the introduction of infection, damage to neurovascular structures, local fat pad and skin atrophy secondary to the effects of the steroid, skin depigmentation or hyperpigmentation, telangiectasias, and thinning of the skin.14,15 Fat pad atrophy on the dorsal foot is primarily a cosmetic issue. Fat pad atrophy on the plantar aspect of the foot can result in painful ambulation and gait disturbances.19 Skin changes and fat pad atrophy can be prevented by ensuring the injection is deep and properly placed so that the corticosteroids do not leak into the subcutaneous tissues.20 It is common for the pain to recur in days to weeks, even when the injection is successful. Single injections may not totally relieve the patient’s symptoms. The patient often requires a series of injections every 1 to 2 weeks to be successful.
SUMMARY
FIGURE 186-5. Placement of a metatarsal pad.
Morton’s neuroma is one of the most common causes of forefoot pain. Injection therapy is useful in alleviating the symptoms of a neuroma and in confirming the diagnosis. Arrange Podiatric or Orthopedic follow-up for all patients given this diagnosis, as more invasive procedures may be needed for long-term resolution of symptoms.
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SECTION
Miscellaneous Procedures
187
Relief of Choking and Acute Upper Airway Foreign Body Removal Tamara Espinoza, Shekhar Menon, and John Bailitz
INTRODUCTION Accidental foreign body obstruction of the airway is the leading cause of accidental death in children less than 6 years of age.1 Airway foreign body obstruction accounts for over 4000 adult and pediatric deaths per year in the United States.1 Tragically, 90% of these deaths occur in children less than 4 years of age, with 65% occurring in infants.2 The most common cause of an airway foreign body obstruction in infants are feeding liquids while the most common etiologies in older children are candy, grapes, peanuts, and vegetables. Mortality due to airway foreign body obstruction is bimodal and increases again in the elderly, with 13.6 deaths per 100,000 people greater than 75 years of age.3,4 Food impaction is the primary etiology with the elderly, with those intoxicated and institutionalized being at an increased risk.3,4
ANATOMY AND PATHOPHYSIOLOGY The clinical presentation and patient management is dependent on three related factors: the anatomical site of obstruction, the degree of obstruction, and the size of the foreign body. Autopsy reports have found the foreign body obstruction to be located supraglottic in 32% and infraglottic in 68%.5 Patients with a supraglottic obstruction classically present with inspiratory stridor while those with an infraglottic obstruction present with expiratory wheezes. Infraglottic foreign bodies lodge in the trachea or the mainstem bronchus and require instrument removal. A foreign body that simply contacts the vocal cords while moving through the glottis may result in laryngospasm that can completely obstruct the airway, even after the expulsion of the foreign body.6 Partial airway obstructions often allow limited amounts of air passage and their removal by the patient’s cough reflex. Complete airway obstructions can result in a silent cough followed by loss of consciousness, thus requiring higher pressures for removal. A larger foreign body is more likely to lodge above or at the vocal cords causing a complete airway obstruction. Sharp, small, and thin foreign bodies are more likely to obstruct between or below the vocal cords and result in difficulty breathing and odynophagia.7 Pediatric and adult patients provide different clues to an airway foreign body obstruction. Adults and older children typically indicate the “universal choking sign” by clutching or pointing to their neck and nodding affirmatively when asked if choking. An infant or toddler will present after a witnessed or suspected acute foreign body ingestion. Their symptoms range anywhere on a spectrum from subtle stridor and wheezing to cyanosis and unconsciousness.8
16
Dr. Henry Heimlich first proposed the Heimlich maneuver in 1974. Controversy soon followed as he publicly denounced the recommendations made by the American Red Cross and the American Heart Association. He claimed that back blows previously listed as a first-line treatment were “death blows” and that various national organizations were involved in “Watergate cover-ups” intended to prevent acceptance and widespread use of his maneuver. No prospective clinical trials have been reported on the various techniques used to relieve an airway foreign body obstruction. Physiologic data demonstrate that each technique produces varying effects on intrathoracic pressure and airflow to overcome the static resistance of the obstructing foreign body.9 Back blows generate a substantial increase in intrathoracic pressure over a very short period of time, potentially dislodging an airway foreign body without its expulsion from the airway. Conversely, abdominal thrusts generate more prolonged increases in airway pressure and flow rates, theoretically allowing for expulsion of the dislodged foreign body. Rescuers must be prepared to quickly utilize a combination of these techniques for the dislodgement and expulsion of an airway foreign body obstruction.4
DIGITAL REMOVAL (FINGER SWEEP) Perform digital removal of an intraoral foreign body only when it is directly visualized in the patient’s mouth or oropharynx. Blind finger sweeps are contraindicated to prevent inadvertently pushing the foreign body into a more distal location, thereby converting an incomplete supraglottic obstruction into a difficult to remove and complete infraglottic obstruction.7 Open the patient’s mouth and airway using the thumb and fingers of the nondominant hand to grab the tongue and mandible then lift it anteriorly. Use a hooking action with the index finger of the dominant hand to dislodge and remove the foreign body. The most important potential complication is the conversion of a partial airway obstruction into a complete airway obstruction. Local trauma can result in intraoral abrasions, bleeding, and dental trauma. The rescuer can sustain digital abrasions and lacerations from the patient’s teeth. Do not place your fingers into the mouth of a conscious patient as this can result in a significant bite injury.
BACK BLOWS AND CHEST THRUSTS IN INFANTS An uncoordinated swallow mechanism and the lack of molar dentition predispose the infant to an airway foreign body obstruction within their narrow and pliable glottis and trachea.10 Perform back blows and chest thrusts on the infant with a witnessed or suspected airway foreign body obstruction who suddenly develops respiratory distress, appears cyanotic, or becomes unconscious. This technique should be used on infants less than 1 year of age. Use the Heimlich maneuver if the patient is over 1 year of age. Continue to closely observe the infant but do not intervene if they are maintaining their airway as indicated 1181
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FIGURE 187-1. Relief of an airway foreign body obstruction in the infant. A. Back blows using the heel of a hand. B. Chest thrusts using the heel of a hand. C. Chest thrusts using two fingers. D. Chest thrusts using both thumbs.
by clear breathing and an effective cough. Their cough reflex may allow them to dislodge and expel the foreign body. Place the choking infant with their head angled down in a prone position over the arm or thigh of the rescuer (Figure 187-1A). This head-down position allows gravity to assist in the expulsion of the dislodged foreign body. Perform five firm back blows with the heel of a hand between the infant’s shoulder blades (Figure 187-1A). Turn the infant around into the supine position with their head angled down. Perform five chest thrusts with the heel of a hand applied to sternum (Figure 187-1B). Repeat this sequence of back blows and chest thrusts until the foreign body is expelled or the infant becomes unresponsive. Chest thrusts may also be performed using two other methods. The first is to apply the index and middle fingers just below the intermamillary line and compress the chest (Figure 187-1C). This is usually performed when there is one rescuer. The second method is to use both thumbs on the infant’s sternum (Figure 187-1D). This method is performed when one or two rescuers are present. Place both thumbs together over the lower half of the infant sternum just below the intermamillary line. Encircle the infant’s chest with both hands, spreading the fingers around the posterior thorax. Compress the sternum while squeezing the thorax to apply counterpressure.
The procedure is successful when the foreign body is expelled. Closely observe the infant after expulsion of the foreign body for any signs of persistent respiratory distress due to an incompletely expelled foreign body or injury from the removal techniques. For the unresponsive infant, first check their mouth and remove any obvious foreign body. Blind finger sweeps are always contraindicated. Case reports describe wedging of foreign bodies into more distal locations and converting a partial airway obstruction into a complete airway obstruction.7 In the apneic infant, immediately begin more advanced pediatric procedures as described below as well as Basic Life Support and Advanced Life Support maneuvers. Back blows often result in back and chest wall contusions. The use of acetaminophen or nonsteroidal anti-inflammatory drugs should relieve any discomfort. Vigorous back blows can result in rib fractures. Occasionally, nausea and vomiting can result. Chest thrusts may result in rib and sternal fractures, myocardial contusions, punctured lungs, pneumothoraces, and intraabdominal injury.4 While these potential complications are serious, not relieving an airway foreign body obstruction can result in death. Maintain a low threshold for performing back blows and chest thrusts to relieve an airway foreign body obstruction in infants. An
CHAPTER 187: Relief of Choking and Acute Upper Airway Foreign Body Removal
airway foreign body obstruction in an infant is more likely, more difficult to assess, and more often fatal than in an older child, adolescent, and adult. The key steps to remember include positioning the infant head down over the rescuer’s arm or leg with their head lower than their trunk, performing five back blows alternating with five chest thrusts, and repeating this sequence continuously until the foreign body is expelled.
ABDOMINAL THRUSTS (HEIMLICH MANEUVER) IN THE CONSCIOUS PATIENT Perform the Heimlich maneuver in the conscious patient over 1 year of age with a witnessed or presumed aspiration who cannot speak, cough, or breathe effectively. Older children and adult patients will often present and be grasping or pointing to their neck with the “universal choking sign” (Figure 187-2). Young children will often have a history or presentation consistent with an airway foreign body obstruction. As long as the patient is conscious and has signs of a complete airway obstruction, perform this technique from behind. Do not perform the Heimlich maneuver in patients less than 1 year of age due to the significant risk of liver injury.11 Observe the patient closely while their cough reflex attempts to expel the partial obstruction if they are able to cough, speak, and breathe effectively. Perform abdominal thrusts only for a complete airway obstruction. Stand directly behind the patient (Figure 187-2). Wrap both arms around the patient’s waist. Make a fist with one hand. Place this hand with the thumb side of the fist against the midline of the patient’s upper abdomen, between the rib cage and umbilicus.
FIGURE 187-2. The Heimlich maneuver in a conscious patient.
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Place the other hand over the fisted hand and grasp the fisted hand (Figure 187-2). Press inward with a deliberate and quick upward thrust. Confine the force of the thrust to the hands without squeezing the rib cage. Repeat the quick upward thrusts until the foreign body is expelled or the patient becomes unresponsive. Closely observe the patient after the foreign body is expelled for signs of respiratory distress from persistent obstruction or from injury from the Heimlich maneuver. If the patient becomes unresponsive, lay them supine and perform abdominal thrusts as described below. Incorrect hand placement can result in sternal and rib fractures. Significant but rare complications include a punctured lung, pneumomediastinum, and intraabdominal trauma (e.g., liver laceration, splenic laceration, and bowel injury). While these potential complications are serious, not relieving an airway foreign body obstruction can result in death.
ABDOMINAL THRUSTS IN THE UNCONSCIOUS PATIENT Perform abdominal thrusts in the patient with a witnessed or suspected airway foreign body obstruction, failure of the previously described maneuvers, or in the unresponsive patient. Do not perform this maneuver in patients less than 1 year of age due to the significant risk of liver injury. Place the patient supine on a firm surface, usually on the floor. A bed is not firm enough to allow the appropriate generation of intraabdominal pressure. Open their mouth. Perform a finger sweep only if a foreign body is clearly visible. Place the heel of one hand in the midline of the abdomen and just above the umbilicus. Place the other hand over the first (Figure 187-3). Apply five rapid and forceful thrusts downward and upward, forcing the diaphragm upward and compressing the lungs. Reassess the patient’s airway. Inspect their mouth for a foreign body. Remove the intraoral foreign body if it is visible. If the foreign body is not visible, repeat the abdominal thrusts or attempt another technique. One case study reported that increased airway pressure was generated using a knees-to-chest approach in the supine position. While there are no further studies to support this technique, it may be a simple adjunct when other methods have failed.12
FIGURE 187-3. Abdominal thrusts in the unconscious patient.
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Frequently reassess the patient for spontaneous breathing. Each time the mouth and airway is opened, look for a foreign body prior to ventilation attempts. Closely observe the patient after the foreign body is expelled for signs of respiratory distress from persistent obstruction or from injury from the abdominal thrusts. Incorrect hand placement can result in sternal and rib fractures. After the foreign body is removed, place the patient in the semirecumbent position or sitting upright if no contraindications exist. Reported complications include abdominal pain, vomiting, pharyngeal abrasions, esophageal lacerations, intraabdominal trauma (e.g., liver laceration, splenic laceration, and bowel injury), fractured ribs, punctured lung, pneumothoraces, a pneumomediastinum, and even retinal detachment. While these potential complications are serious, not relieving an airway foreign body obstruction can result in death.
DIRECT LARYNGOSCOPY Developmental differences in the pediatric airway make visualization and removal of foreign bodies more difficult than in the adult patient. The pediatric tongue occupies a larger percentage of the oral cavity and the oropharynx. Their epiglottis is larger, U-shaped, and more cephalad. The pediatric epiglottis does not attain the adult position until age four. The narrowest portion of the pediatric airway, and a likely site of obstruction, is below the vocal cords at the level of the cricoid cartilage, making removal more difficult. The timing of endoscopy and airway foreign body retrieval must be based upon each individual patient. Do not waste time if impending airway obstruction exists. Immediately notify and mobilize an Anesthesiologist, Otolaryngologist, and the Operating Room, as this is an emergent situation. It is appropriate to wait for NPO status to be present and the stomach empty prior to proceeding to the Operating Room if the diagnosis of an airway foreign body is highly suspected and the patient is stable. This is considered a timely approach and may take up to 6 hours for children or 8 hours for adults. Waiting this time in the stable patient decreases the risk of aspiration and further compromising the situation. It is also appropriate to wait, in a stable patient, in order to assemble the appropriate and best nursing and anesthesia team to care for the patient. Using personnel who are unfamiliar with endoscopy can create a compromised and stressful situation. It is always best not to manipulate the airway or attempt intubation in a stable patient with an airway foreign body and who is moving air and breathing. The airway may be best controlled in the Operating Room at the time of the actual foreign body removal. Once the airway is manipulated a foreign body can become dislodged, turning a partial airway obstruction into a complete airway obstruction. If this occurs in the Operating Room, the bronchoscopy equipment is available for urgent use by the endoscopist if needed. It is possible to remove foreign bodies located within the hypopharynx in the Emergency Department. Typical foreign bodies that may be removed include pieces of food and fishbones. The patient must be stable and in no risk of airway compromise. Obtain anteroposterior and lateral soft tissue radiographs of the neck to localize, if possible, the foreign body. The use of CT scans to attempt to identify potential fish or chicken bones that may be lodged in the pharynx, hypopharynx, or esophagus is an option in the stable patient. Perform indirect laryngoscopy to identify the foreign body and its location. Refer to Chapter 173 regarding the complete details of laryngoscopy. Obtain intravenous access. Perform a forceps removal of an airway foreign body in the patient with a complete airway obstruction or severe respiratory distress due to partial obstruction when less invasive measures have failed.13 Do not try to blindly grasp for a presumed airway foreign
body. Observation and removal in the Operating Room, and not an Emergency Department intervention, is indicated in the patient who is coughing, speaking, or otherwise breathing effectively. Begin with less invasive techniques before performing direct laryngoscopy and manual removal. Be ready to utilize multiple laryngoscope blades, clamps, and forceps to safely visualize and remove accidental foreign body obstruction.
EQUIPMENT • • • • • • • • • • •
Topical anesthetic spray (e.g., Cetacaine) Laryngoscope Laryngoscope blades, Miller and Macintosh, various sizes Tracheal suction catheter Magill forceps Pulse Oximeter Cardiac Monitor Noninvasive blood pressure cuff Oxygen Video laryngoscope, optional Surgical airway equipment
Direct laryngoscopy and bronchoscopy in a child or adult with an airway foreign body is a dangerous situation. The procedure may result in a partial airway obstruction becoming a complete airway obstruction. Always have a cricothyroidotomy tray and/or percutaneous transtracheal jet ventilation device immediately available. All equipment must be selected, assembled, and ready for use. Place the patient in full monitoring (i.e., pulse oximeter, cardiac monitor, and noninvasive blood pressure cuff). Apply a topical anesthetic spray to the oropharynx and the base of the tongue to blunt the gag reflex. Place the patient supine or semirecumbent. Administer a small dose of an intravenous sedative if required and not contraindicated. Slowly and gently insert the laryngoscope blade. An alternative to a traditional laryngoscope, if available, is a video laryngoscope. The video laryngoscope may provide a better field of view with less manipulation. Do not immediately insert the laryngoscope blade all the way. Stop frequently to lift the laryngoscope and look for the foreign body. This slow insertion and frequent looks will prevent the laryngoscope blade from pushing the foreign body further into the airway. Elevate the patient’s tongue and jaw. Grasp the foreign body with a Magill forceps. If the foreign body is too large or impacted, it may need to be crushed with the forceps to securely grasp it as a whole piece.14 Withdraw the McGill forceps followed by the laryngoscope. One case report describes passing a Foley catheter distal to the foreign body under direct visualization with a laryngoscope.14 The balloon was then inflated with 5 mL of air and subsequently pulled back until the foreign body could be grasped and removed with a Magill forceps. There were no reported complications. However, it should be noted the foreign body in this case was impacted within the esophagus at the level of the cricoid cartilage. Do not use this technique with subglottic airway foreign bodies since retraction of a dilated catheter balloon through the glottic structures may cause injury, edema, bleeding, and further worsen the obstruction. Observe the patient for persistent or delayed respiratory distress resulting from incomplete removal or procedural complications. The severity of the obstruction determines whether a patient may be safely discharged home or admitted for observation. One review reported no complications with subglottic foreign body removal when utilizing Magill forceps under direct
CHAPTER 188: Induction of Therapeutic Hypothermia
laryngoscopy.13 Potential complications include oropharyngeal trauma resulting in glottic edema and bleeding.
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bronchi to allow ventilation of at least one lung, or a surgical airway performed. Failure to react appropriately in this situation can result in asphyxiation and death.
OROTRACHEAL INTUBATION Attempt orotracheal intubation in the Emergency Department if the airway obstruction progresses rapidly and the patient cannot ventilate. Intubation can be used to force the foreign body into one mainstem bronchus and allow ventilation of the other lung. One-lung ventilation will keep the patient alive until the foreign body can be removed in the Operating Room. Position the laryngoscope to visualize the larynx. If a foreign body is visualized, grasp the foreign body with a McGill forceps and remove it. If no foreign body is visualized, intubate the patient. Insert and advance the endotracheal tube as far as it will advance if the foreign body is not visualized or unable to be grasped. If the endotracheal tube will not pass, try passing a smaller size endotracheal tube. Withdraw and position the endotracheal tube with the tip above the carina to optimize ventilation. As an alternative, properly insert and position the endotracheal tube above the carina then advance a bougie through the endotracheal tube in an attempt to move the foreign body distally. Always be prepared to perform a cricothyroidotomy or transtracheal jet ventilation. Transtracheal jet ventilation allows for short-term oxygenation, is temporary, and may allow time for safe transport to the Operating Room so that endoscopy and foreign body retrieval can be performed in a more controlled environment with appropriate equipment at hand. Refer to Chapters 11, 25, and 24 regarding the details of orotracheal intubation, cricothyroidotomy, and transtracheal jet ventilation, respectively.
SUMMARY An airway foreign body obstruction is a significant cause of preventable morbidity and mortality in the pediatric, debilitated, and elderly patients. Prompt recognition and management is vital to preventing cardiopulmonary arrest. Do not intervene in the awake patient who is talking, coughing, or otherwise breathing effectively. Observe these patients to determine if their own cough reflex can expel the foreign body. Perform the age and condition appropriate maneuvers with a complete airway obstruction or severe respiratory distress with a partial airway obstruction. Multiple attempts with a combination of procedures are often required for the successful removal of an airway foreign body. Back blows and chest thrusts are first line for infants while abdominal thrusts may be performed on all others. Blind finger sweeps are always contraindicated. Perform manual removal with finger sweeps or direct laryngoscopy under direct visualization.
188
Induction of Therapeutic Hypothermia Mark Hansen, Mike Nelson, and John Bailitz
AFTERCARE
INTRODUCTION
After the extraction, removal, or retrieval of an airway foreign body, most patients should be breathing spontaneously. An endotracheal tube may rarely, in the presence of significant laryngeal or tracheobronchial edema, need to remain in place temporarily. This would require admission to an intensive care unit. Humidified oxygen is helpful to keep the airway moist and prevent mucous crusts from forming. A postprocedural radiograph will help to determine any subcutaneous air, air in the soft tissues, a pneumothorax, or any changes to the lung fields following the extraction. All patients who have undergone foreign body extraction, removal, or retrieval require at least a few hours of airway observation in a monitored setting. Racemic epinephrine treatments and intravenous Decadron can be administered as needed. Discharge from the hospital is acceptable when the patient is breathing comfortably and no longer in danger of airway compromise. Some patients may be discharged home the same day, while others may require multiple days of airway support and observation.
Sudden cardiac death claims approximately 450,000 victims in the United States every year.1 The mortality rate for out-of-hospital cardiac arrest remains a staggering 65% to 95%, with only 10% to 20% of survivors discharged from the hospital with a good neurologic outcome.2 Therapeutic hypothermia for the treatment of comatose survivors of cardiac arrest is the only therapy proven to improve survival and neurological outcome.3 Although many consider therapeutic hypothermia to be a relatively new concept, experiments with deep therapeutic hypothermia actually began in the 1940s with initially mixed results. In the 1950s, studies examining moderate hypothermia in the range of 26°C to 32°C (78.8°F to 89.6°F) in comatose survivors of cardiac arrest reported a trend toward improved outcomes but were complicated by difficult to control side effects. Additional animal studies of mild hypothermia in the range of 32°C to 35°C (89.6°F to 95°F) in the 1980s and small clinical trials in the 1990s demonstrated that even mild hypothermia provided the protective benefits with far fewer side effects.2 Two landmark randomized trials published in 2002 specifically examined the use of mild hypothermia in comatose survivors of witnessed cardiac arrests with initial rhythms of pulseless ventricular tachycardia or ventricular fibrillation.4,5 More recent meta-analysis report that only seven patients need to be treated to save one life and only five patients need to be treated to prevent one poor neurological outcome.6,7 Utilizing these studies’ strict screening criteria resulted in only 10% of screened patients being eligible. Follow-up studies suggest a wider benefit in patients with other rhythms at presentation, cardiogenic shock, and those requiring percutaneous cardiac intervention (i.e., angioplasty and stenting).2,3,8–16 Preliminary studies of therapeutic hypothermia for other indications including traumatic brain injury, strokes, subarachnoid hemorrhages, myocardial infarctions, and ARDS have to date reported
COMPLICATIONS Complications from the foreign bodies themselves include hypoxia leading to cerebral anoxia if not identified. Cardiac arrhythmias can occur from hypoxia or direct pressure on the left main-stem bronchus. Other complications include laryngeal or tracheobronchial edema from the foreign body or the instrumentation of the airway. Mucosal irritation can instigate a bronchitis, pneumonia, or tracheitis. A pneumomediastinum and/or a pneumothorax is possible. The complications specific for each technique have been described previously in the respective sections. A foreign body in the hypopharynx can be pushed distally and result in a total airway obstruction. The foreign body needs to be quickly removed, pushed back down into one of the mainstem
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only limited data or conflicting results. The exception being studies of neonates with perinatal asphyxia that reported similar results to adult cardiac arrest with a number needed to treat of six for one favorable outcome.3 Extensive ongoing research is currently being conducted to determine the effectiveness of therapeutic hypothermia for other indications, as well as the optimal timing, duration, target temperature, and best techniques. Despite recommendations for therapeutic hypothermia in the 2005 International Liaison Committee on Resuscitation Recommendations and American Heart Association Resuscitation Guidelines, a recent survey showed that 74% of physicians in the United States had not used therapeutic hypothermia.15 They cited reasons such as not enough data, not part of ACLS protocol, too technically difficult, or that it had not been considered.15 However, the induction of therapeutic hypothermia for comatose survivors of cardiac arrest is relatively straightforward in any Emergency Department. Similar to Early Goal Directed Therapy (EGDT) for septic shock, the creation of collaborative protocols between Emergency Physicians, Intensivists, Cardiologist, and Neurointensivists is essential to producing the best outcomes at each institution.
ANATOMY AND PATHOPHYSIOLOGY The postcardiac arrest syndrome has recently been defined as a complex pathophysiological process involving brain injury, myocardial dysfunction, systemic ischemia and reperfusion response, and the underlying persistent precipitating pathology.3 Brain injury is the reported cause of death in two-thirds of patients after an out-ofhospital arrests and one quarter of patients after in-hospital cardiac arrests.16 Multiple cellular mechanisms contribute to neuronal apoptosis and necrosis including the formation of free radicals, disruption of calcium homeostasis, excitotoxicity, altered gene expression, mitochondrial dysfunction, and inflammation. At the tissue level, these cellular mechanisms lead to failure of cerebral autoregulation and ultimately hypotension, hypoxemia, brain edema, pyrexia, hyperglycemia, and seizures.3 Surprisingly, the postcardiac arrest state does not result in myocardial infarction but only myocardial stunning for 24 to 48 hours, producing a reduced ejection fraction and a reduction in end organ oxygen delivery.3 The accumulated oxygen debt activates an inflammatory endothelial response further worsening oxygen delivery. The vicious cycle of oxygen debt and resultant inflammation does not end with reperfusion. Instead, the burst of reactive oxygen intermediates further exacerbates the inflammatory response and organ injury. The resultant state of systemic ischemia with reperfusion response leads to intravascular volume depletion, changes in vasoregulation, decreased oxygen utilization and delivery, and an increased risk of infection. The underlying persisting pathology that caused the cardiac arrest also must be addressed. Acute coronary syndrome is strongly implicated in up to 50% of out-of-hospital cardiac arrests.10 Elevations of troponin T are present in up to 40% of patients at the time of cardiac arrest, suggesting an ongoing cardiac ischemia or injury hours prior to the cardiac arrest. Additional etiologies of the cardiac arrest to consider include pulmonary embolism, primary pulmonary disease, sepsis, drug toxicity, or severe hemorrhage. Hypothermia improves outcomes through several proposed mechanisms.17 Metabolic demand is reduced 5% for each degree Celsius reduction in core body temperature. At the cellular level hypothermia decreases adenosine triphosphate demand, preventing intracellular acidosis and stabilizing cell membranes. At the tissue level hypothermia leads to decreased vascular permeability at the blood–brain barrier thus decreasing edema. Hypothermia interrupts the inflammatory cascade by inhibiting neutrophils,
reducing the production of proinflammatory cytokines, and helping to prevent the free radical production associated with reperfusion injury.
INDICATIONS Hypothermia is most effective in patients meeting the strict inclusion criteria of the initial landmark studies. Begin the induction of hypothermia in the Emergency Department for comatose survivors of cardiac arrest with a presumed cardiac etiology, an initial rhythm of ventricular fibrillation or pulseless ventricular tachycardia, and between 18 and 75 years of age.3,7 More recent studies have demonstrated improved outcomes in patients with other initial rhythms (e.g., pulseless electrical activity and asystole), comatose survivors of in-hospital cardiac arrest, patients requiring percutaneous cardiac intervention, and those suffering from cardiogenic shock.10,11,13,14,18 Consider the induction of therapeutic hypothermia when the cardiac arrest is witnessed, there is 80 mmHg with or without IV fluid boluses and pressors. Refer to Figure 188-1 regarding a sample induction of therapeutic hypothermia checklist and clinical pathway.
CONTRAINDICATIONS Hypothermia is contraindicated in patients with a known status of do not resuscitate (DNR) or do not intubate (DNI), have a terminal illness, have severe comorbidities, have multiorgan failure prearrest, or are comatose due to a noncardiac etiology. Patients with a preexisting coagulopathy or pregnancy have been excluded from most studies. One case of successful therapeutic hypothermia in pregnancy has been reported.19 Other contraindications include patients when prehospital or in-hospital resuscitation is initiated greater than 15 to 30 minutes after collapse, with >60 minutes from the time of arrest to the ROSC, who are persistently hypoxic (SpO2 < 85%) for greater than 15 minutes after the ROSC, if the arrest is related to blunt or penetrating trauma, when greater than 6 hours have elapsed since the ROSC, and if the patient spontaneously awakens with a normal mental status.
EQUIPMENT General Supplies • Arterial line equipment and supplies (Chapter 57) • Nasogastric tube equipment and supplies (Chapter 58) • Cardiac Monitor • Ventilator • Orotracheal intubation equipment and supplies (Chapter 11) • Venous access equipment and supplies (Chapters 48 and 49) • Analgesics (e.g., Fentanyl, Morphine, or Meperidine) • Sedatives (e.g., Propofol, Ativan, or Versed) • Neuromuscular blockers (e.g., Pancuronium, Vecuronium, or Rocuronium) • Defibrillator–cardioverter unit and supplies (Chapter 30) Cooling Supplies • 4°C sterile normal saline or lactated Ringers • Ice packs or ice water-soaked blankets • Core temperature probe and monitor (e.g., esophageal, rectal, or urinary)
CHAPTER 188: Induction of Therapeutic Hypothermia
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Induction of therapeutic hypothermia in the emergency department Inclusion and exclusion criteria: All must be checked to proceed Non-traumatic cardiac arrest with ROSC 0.5 mL/h/kg) Check labs (BMP, Ca, Mg, Phos, CBC, Coag, Trop, CKMB, UA, Urine pregnancy, ABG)
Induction: Rapidly achieve mild hypothermia in 37°C) for 72 h, use acetaminophen and cooling blanket if necessary Stop neuromuscular blockade, if shivering occurs treat with warm blanket and meperidine (15 mg every 2 h as needed) Anticipate hypotension and electrolyte abnormalities during rewarming
FIGURE 188-1. A sample induction of therapeutic hypothermia checklist and clinical pathway.
External Commercial Cooling Devices (Figure 188-2) • Excel Cerebral Cooling System (Life Core Technologies LLC, Cleveland, OH) • Medi-Therm III (Gaymar Industries Inc., Orchard Park, NY) • Arctic Sun Temperature Management System (Medivance Inc., Louisville, CO)
• Cincinnati Sub-zero Blankets (Cincinnati Sub-zero Products Inc., Cincinnati, OH) • InnerCool STx Surface Pad Systems (Phillips Healthcare, San Diego, CA) • Thermosuit (Life Recovery Systems, Waldwick, NJ)
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B
A
D
C
FIGURE 188-2. Examples of externally applied cooling devices. A. The Excel Cerebral Cooling System (Photo courtesy of Life Core Technologies LLC, Cleveland, OH). B. The Arctic Sun Temperature Management System (Photo courtesy of Medivance Inc., Louisville, CO). C. The Cincinnati Kool-Kit (Photo courtesy of Cincinnati Sub-zero Products Inc., Cincinnati, OH). D. The Thermosuit (Photo courtesy of Life Recovery Systems, Waldwick, NJ). E. The Medi-Therm (Photo courtesy of Stryker Medical, Orchard Park, NY).
Internal Endovascular Cooling Devices (Figure 188-3) • Accutrol catheter (Phillips Healthcare, San Diego, CA) • Cool Line, Icy, and Quattro catheters (Alsius, Irvine, CA) Nasal cooling systems are currently being developed and tested (BeneChill, San Diego, CA and Johns Hopkins University, Baltimore, MD). These systems take advantage of the large surface area of the nasal cavity with an abundant capillary supply just below the mucosa as a heat exchanger. Early studies are promising. These systems may be used prehospital as well as in-hospital for
E
the cooling of the postcardiac arrest patient. Further development and testing is required before these devices will be available for use.
PATIENT PREPARATION Carefully consider inclusion and exclusion criteria for each individual patient utilizing pre-established institution-specific protocols. The risks, benefits, potential complications, and aftercare of the procedure should be explained to the patient’s representative and an informed consent obtained whenever possible. The postarrest
CHAPTER 188: Induction of Therapeutic Hypothermia
A
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FIGURE 188-3. Examples of internally applied cooling devices. A. The Icy catheter (Photo courtesy of Alsius, Irvine, CA). B. The Accutrol catheter (Photo courtesy of Phillips Healthcare, San Diego, CA).
patient will be or should be intubated, have continuous pulse oximetry and cardiac monitors, and have frequent automated cuff or continuous arterial line blood pressure monitoring. Perform a detailed examination to document a postarrest comatose state and the patient’s baseline neurologic status including Glasgow Coma Scale, pupillary light reflex, corneal reflex, facial movements, eye movements, gag, cough, and motor response to painful stimuli. The retention of any neurologic function during or after cardiopulmonary resuscitation suggests a good prognosis. However, the absence of neurologic function immediately after the ROSC is not a reliable predictor of a poor outcome. The reliability of the neurologic exam to predict a poor outcome is time dependent. The absence of pupillary light reflexes, corneal reflexes, or motor responses to painful stimuli at day 3 provides the most reliable predictor of poor outcome.3 Prepare the patient for therapeutic hypothermia. Turn the ventilator’s warm humidified air function off so as not to warm the patient. Perform an ECG. Obtain basic laboratory analyses to include electrolytes, renal function, calcium, magnesium, phosphorus, complete blood count, coagulation profile, cardiac markers, urinalysis, pregnancy, and arterial blood gas. Other laboratory analyses may include cortisol levels and thyroid function tests at the discretion of the admitting team. Titrate intravenous sedation and analgesia for comfort with mechanical ventilation. Shivering increases oxygen consumption, requiring control with low dose meperidine (15 mg IV Q 2 hours) and possibly neuromuscular blockade. Place a urethral catheter (Chapter 142) and monitor the urine output with a goal of >0.5 mL/hour/kg. Continuously monitor the core temperature with an esophageal, rectal, or urinary temperature probe. Place a nasogastric tube. Apply defibrillator/pacing pads (Chapter 30) in case they are required during the therapeutic hypothermia process. Otherwise, standard acute coronary syndrome and postresuscitation protocols apply.
TECHNIQUE Therapeutic hypothermia is performed in three phases: induction, maintenance, and rewarming. There are multiple methods to perform all three phases. However, the goals of each phase always remain the same. Rapidly achieve a hypothermic state of 32°C
to 34°C (89.6°F to 93.2°F), maintain hypothermia for at least 12 to 24 hours, and then slowly rewarm at no faster than 0.25°C to 0.50°C (0.45°F to 0.9°F) per hour.
INDUCTION Beginning the induction phase of therapeutic hypothermia in the Emergency Department is straightforward and inexpensive. The typical temperature decrease seen in survivors of cardiac arrest begins the process even before it starts. The infusion of 4°C normal saline or lactated Ringers stored in a temperature-controlled refrigerator provides a reliable and safe method for rapid induction. Bolus 30 mL/kg or 1.5 to 2 L of fluid to create a 1.5°C to 2.3°C (2.7°F to 4.1°F) decrease in temperature.20–22 Monitor the patient for signs of fluid overload and adjust the rate and total volume accordingly. Smaller repeat boluses of 500 mL may be given when required.17 The application of ice packs to the head, neck, torso, and groin provides another safe and reliable method for rapidly decreasing temperature.23 Patients requiring immediate angiography or admission to other locations may be transferred with both of these methods in place and without delay.10,13 Several commercially available external and internal cooling devices listed in the equipment section allow the Emergency Physician to set and maintain a target temperature through the use of continuous feedback from the patient’s core temperature monitor. External systems utilize cooled circulated air, pads, or blankets. Internal systems require the placement of a femoral or subclavian central venous catheter with an endovascular cooling device. When available, these devices should be initiated while the fluid boluses and/or ice packs are applied. To date there have been no studies comparing external versus internal cooling devices in cardiac arrest patients.23 However, a manufacturer sponsored study of therapeutic hypothermia in neurosurgical patients demonstrated that the endovascular device reached target temperature faster (35 vs. 204 minutes), maintained a tighter control of target temperature, and had no significant increase in complications versus surface cooling.24 Beginning the induction in the Emergency Department with cooled IV fluids and ice packs, followed by the immediate transfer of the patient to the Intensive Care Unit for the application of more
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expensive and delicate commercial cooling devices for maintenance of therapeutic hypothermia provides a clinically and cost-effective approach in any institution. These commercial cooling devices should be applied and the process of therapeutic hypothermia continued in the Emergency Department if there is any delay in transferring the patient to the Intensive Care Unit.
MAINTENANCE Cooling should be stopped at 33.5°C (92.3°F) to prevent overshoot.17 Use an external or internal cooling system with feedback control to maintain a core temperature of 32°C to 34°C (89.6°F to 93.2°F). Other methods include the use of cold wet blankets and ice packs placed around the head, neck, torso, and extremities. Although less expensive, these methods are more labor intensive, result in greater temperature fluctuations, and do not allow for controlled rewarming.25 Maintaining hypothermia with fluid boluses alone is not possible.26 Supportive therapy with continuous cardiac monitoring should occur in the Intensive Care Unit setting. Continue administering analgesics, sedatives, and neuromuscular blockade as required. Maintain a goal mean arterial pressure of 65 to 100 mmHg with a central venous pressure of 8 to 12 mmHg. Monitor urine output and laboratory values to best manage the resulting cold diuresis. Maintain tight glucose control (108 to 144 mg/dL) to improve survival and neurologic outcomes.3
REWARMING Rewarming typically begins 24 hours after the initiation of cooling. Gradual rewarming at a rate of 0.25°C to 0.5°C (0.45°F to 0.9°F) an hour over a 6 to 8 hour period helps prevent rapid changes in metabolic rate, electrolyte levels, and hemodynamics. Techniques include passive rewarming, resetting the temperature on commercial devices, and the application of heated-air blankets when needed. Discontinue analgesics, sedatives, and neuromuscular blockade during the rewarming phase. In the landmark studies, Bernard stopped the neuromuscular blockade before 24 hours, while Holzer maintained blockade for 32 hours. Other published protocols call for medications to be held when the core temperature reaches 35.5°C to 36.5°C (95.9°F to 97.7°F). Treat shivering during the rewarming with a warm blanket and low dose meperidine.27 Care must be taken to avoid hyperthermia/pyrexia (>37.5°C or 99.5°F) by treating with antipyretics and active cooling for 72 hours postarrest. Hypotension and hyperkalemia commonly occur during rewarming.3 This requires close monitoring of the patient, the ECG tracings, and periodic laboratory analysis.3 Detailed protocols for therapeutic hypothermia from several institutions are available through the University of Pennsylvania’s Center for Resuscitation Science at http://www.med.upenn.edu/ resuscitation/hypothermia/protocols.shtml.
TECHNIQUE FOR PEDIATRIC PATIENTS Although patients under the age of 18 were excluded from the landmark studies, the 2005 International Liaison Committee on Resuscitation recommends that the induction of hypothermia should be considered for 12 to 24 hours in children who remain comatose after resuscitation from a cardiac arrest. There are currently no published studies of the use of therapeutic hypothermia for pediatric survivors of a cardiac arrest. However, neonates with perinatal asphyxia have been treated successfully with external cooling elements for 72 hours with impressive results.28 Consult
a Pediatric Intensivist and Pediatric Cardiologist prior to inducing hypothermia in a patient under the age of 18 years. After considering the risks and benefits of therapeutic hypothermia, begin induction and maintenance with the techniques described previously.
AFTERCARE Consult an Intensivist and Cardiologist. Admit the patient to the appropriate Intensive Care Unit. Therapeutic hypothermia requires Intensive Care Unit admission for ventilator management as well as the continuous monitoring of core temperature, cardiac rhythm, blood pressure, and central venous pressure. Sedatives and paralytics are required for patient comfort and shivering control. Obtain laboratory analyses every 4 hours or as clinically indicated. Further bedside cardiac testing or cardiac catheterization laboratory intervention may be performed by a Cardiologist to help determine and treat the precipitating coronary artery disease. Consult a Neurologist for an electroencephalogram (EEG) and other neurological testing to detect seizures and determine patient prognosis.29 Standard Intensive Care Unit and postcardiac arrest/acute coronary syndrome care should be applied to all patients after completion of therapeutic hypothermia. Consider the use of deep venous thrombosis prophylaxis with sequential compression devices, subcutaneous heparin, or subcutaneous low molecular weight heparin. Apply lacrilube to the patient’s eyes every 4 to 6 hours to prevent a corneal abrasion or corneal ulceration from dry corneas. Consider the use of stress ulcer prophylaxis. Once the 24 hour therapeutic hypothermia period is completed, begin to rewarm the patient and wean any neuromuscular blockade and sedation. Extubation is determined and evaluated on a case-by-case basis.
COMPLICATIONS Despite the proven safety and benefit of therapeutic hypothermia, Emergency Physicians must be aware of several complications. Shivering during the induction phase increases core temperature and oxygen consumption. Low dose meperidine, buspirone, and magnesium have been reported to lower the shivering threshold in awake hypothermic patients.27,30 Magnesium sulfate has the added benefits of improving cooling rates through vasodilatation while acting as an antiarrhythmic.31 Pulmonary edema may occur with cooled IV fluid boluses. Arrhythmias may occur, especially with the use of endovascular cooling techniques. Hypothermic patients may be more susceptible to infection, especially pneumonia and sepsis. The landmark studies showed only an insignificant trend toward increased sepsis. Postcardiac arrest patients are at high risk of developing pneumonia in the first 48 hours, with aspiration being a key risk factor.3 A coagulopathy may occur due to changes in platelet function, clotting factor enzyme function, and fibrinolytic activity. However, thrombolytics, heparin, and aspirin may be safely administered during induction when clinically indicated.14 A cold diuresis may lead to electrolyte abnormalities including hypophosphatemia, hypomagnesemia, hypocalcemia, and hypokalemia, or hyperkalemia. Hyperglycemia must be avoided to improve neurologic outcomes after cardiac arrest and in all critically ill patients. Increases in amylase and a transient rise in renal markers have been reported but are of unclear significance. Decreased core temperature often prolongs the duration of action of neuromuscular blockers such as Vecuronium as well as sedatives including Versed or Propofol.32
CHAPTER 189: Hypothermic Patient Management
The cooling devices themselves may be as source of complications. The endovascular catheter of internal cooling devices increases risk of infections and venous thrombosis similar to any central venous catheter.24 External cooling devices may cause skin breakdown and tissue necrosis.23
SUMMARY The staggering number of sudden cardiac deaths and the often poor neurologic outcomes of survivors place an enormous burden on the healthcare system. Two well done landmark studies in 2002 clearly demonstrated improved survival and neurologic outcomes in comatose survivors of an out-of-hospital cardiac arrest with an initial rhythm of pulseless ventricular tachycardia or ventricular fibrillation treated with mild therapeutic hypothermia of 32°C to 34°C (89.6°F to 93.2°F) for 12 to 24 hours. These results were incorporated into both the 2005 recommendations by the International Liaison Committee on Resuscitation and subsequently by the 2005 American Heart Association Resuscitation Guidelines. These organizations recommend therapeutic hypothermia for comatose survivors of an out-of-hospital cardiac arrest with an initial rhythm of ventricular fibrillation or pulseless ventricular tachycardia. They also recommend the consideration of therapeutic hypothermia in other rhythms and in-hospital cardiac arrests. After establishment of institution-specific multidisciplinary protocols, the induction of therapeutic hypothermia is a straightforward, inexpensive, safe, and effective procedure in any Emergency Department.
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Hypothermic Patient Management Gary An and Nabil Issa
INTRODUCTION Hypothermia is defined as a core body temperature below 35°C. The normal physiologic thermoregulatory responses start to fail once the core body temperature reaches this level, leading to the body’s inability to generate enough heat to maintain bodily functions. Hypothermia can be subdivided into primary and secondary hypothermia.1 Primary accidental hypothermia occurs when a previously normal individual is subjected to an environmental stress. Secondary accidental hypothermia occurs when a predisposing factor leads to disruption of temperature homeostasis and increases the individual’s susceptibility to lesser environmental stresses (e.g., drug intoxication, trauma, and endocrine disorders). Drug intoxication and trauma are acquired conditions that are highly associated with the development of hypothermia.1 There are multiple reasons why trauma patients are at an increased risk to develop hypothermia. These include extended prehospital time, resuscitation with cold (i.e., ambient air temperature) intravenous fluids, exposure to environmental factors, and physiological characteristics of the trauma itself. Both bleeding and hypoperfusion alter thermoregulation. Hypothermia is an independent contributing factor for increased morbidity and mortality in trauma patients, regardless of the patient’s Injury Severity Score (ISS). Hypothermia is associated with an increase in the incidence of coagulopathy, multiple organ failure, length of hospital stay, and mortality.2
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Significant emphasis has been placed on the prevention of hypothermia as well as the early recognition and correction of hypothermia in the prehospital setting. It is important to recognize that hypothermia can also progress after the patient arrives in the Emergency Department. Studies in the trauma population have reported a significant percentage of patients to have a decrease in their core body temperature during their stay in the Emergency Department.3–5 This recognition has led to the development of multidisciplinary approaches to maintaining normothermia as the patient moves through the hospital.6 The importance of continuity and communication in dealing with hypothermia cannot be overstated.
ANATOMY AND PATHOPHYSIOLOGY Hypothermia can be characterized as mild, moderate, and severe. Mild hypothermia is defined as a core temperature of 32.2 to 35°C or 90 to 95°F. Moderate hypothermia is defined as a core temperature of 28 to 32°C or 82.4 to 90°F. Severe hypothermia is defined as a core temperature of less than 28°C or 82.4°F. The scale can be amended in the trauma patient to 34 to 36°C or 93.2 to 96.8°F for mild hypothermia, 32 to 34°C or 89.6 to 93.2°F for moderate hypothermia, and