PEDIATRIC SURGERY : a comprehensive textbook for africa. [2 ed.] 9783030417239, 3030417239

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Emmanuel A. Ameh Daniel J. Mollura Stephen W. Bickler Matthew P. Lungren Kokila Lakhoo Michael R.B. Evans Benedict C. Nwomeh Editors Dan Poenaru Editors

Clinical Medicine Covertemplate Pediatric Surgery for ASubtitle Comprehensive Textbook for Africa Clinical Medicine Covers T3_HB Second Edition Second Edition

1123 3 2

Pediatric Surgery

Emmanuel A. Ameh  •  Stephen W. Bickler  •  Kokila Lakhoo Benedict C. Nwomeh  •  Dan Poenaru Editors

Pediatric Surgery A Comprehensive Textbook for Africa Second Edition

Editors

Emmanuel A. Ameh Division of Pediatric Surgery Department of Surgery, National Hospital Abuja, Nigeria Kokila Lakhoo Department of Pediatric Surgery University of Oxford Oxford, United Kingdom Dan Poenaru Department of Pediatric Surgery Montreal Children’s Hospital Montreal, Québec Canada

Stephen W. Bickler Professor of Surgery & Pediatrics Rady Children’s Hospital, University of California San Diego San Diego, CA USA Benedict C. Nwomeh Department of Pediatric Surgery Nationwide Children’s Hospital, and Department of Surgery, Ohio State University, Colombus, Ohio USA

ISBN 978-3-030-41723-9    ISBN 978-3-030-41724-6 (eBook) https://doi.org/10.1007/978-3-030-41724-6 © Springer Nature Switzerland AG 2020

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The registered company address is: Gewerbestrasse 11, 6330 Cham, Switzerland

V

Associate Editors Abdelbasit E. Ali  Department of Pediatric Surgery, King Saud Medical City, Riyadh, KSA Associate Professor, Faculty of Medicine, University of Khartoum, Khartoum, Sudan Merrill McHoney  Department of Pediatric Surgery, Royal Hospital for Sick Children, Edinburgh, UK Doruk Ozgediz  Department of Surgery, University of California, San Francisco, CA, USA Justina O. Seyi-Olajide  Pediatric Surgery Unit, Department of Surgery, Lagos University Teaching Hospital, Lagos, Nigeria

VII

Contents Volume I I

Basic Principles

1

Pediatric Surgery Specialty and Its Relevance to Africa . . . . . . . . . . . . . . . . . . . . . . 3 Ekene A. Onwuka, Philip M. Mshelbwala, and Benedict C. Nwomeh

2

Neonatal Physiology and Transport . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Larry Hadley and Kokila Lakhoo

3

Respiratory Physiology and Support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 John R. Gosche, Mark W. Newton, and Laura A. Boomer

4

Cardiovascular Physiology and Support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 Mark W. Newton, John R. Gosche, and Laura A. Boomer

5

Fluids and Electrolyte Therapy in the Pediatric Surgical Patient . . . . . . . . . . . . 43 Mark W. Newton, Chun-Sui Kwok, and Kokila Lakhoo

6

Nutrition Support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55 Molly C. Dienhart and Afua A. J. Hesse

7

Haemoglobinopathies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63 G. Olufemi Ogunrinde and Richard Onalo

8

Wound Healing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73 Patricio Lau, Stephanie Cruz, Sundeep Keswani, and Oluyinka O. Olutoye

9

Vascular Access in Children . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89 J. Ken Muma Nyagetuba and Erik N. Hansen

10

Anaesthesia and Perioperative Care . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101 Mark Newton, Olamide O. Dairo, and Stella A. Eguma

11

Pain Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115 Helen Sowerbutts, J. Matthew Kynes, Jonathan Durell, and Kokila Lakhoo

12

Intensive Care . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123 Immaculate W. K. Barasa and Erik N. Hansen

13

Ethics of Pediatric Surgery in Africa . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137 Daniel Sidler, Sharon Kling, Benedict C. Nwomeh, and Peter F. Omonzejele

14

Psychological Issues in Pediatric Surgery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 147 Paris Hosseini, Kathryn Ford, and Kokila Lakhoo

II

Surgical Infections and Infestations

15

Common Bacterial Infections of Surgical Importance . . . . . . . . . . . . . . . . . . . . . . . . 155 Iftikhar Ahmad Jan, Jonathan Durell, and Kokila Lakhoo

VIII Contents

16

Surgical Site Infection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 165 Abdulrasheed A. Nasir, David H. Rothstein, Sharon Cox, and Emmanuel A. Ameh

17

Surgical Complications of Typhoid Fever . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 173 Francis A. Abantanga, David H. Rothstein, and Emmanuel A. Ameh

18

Tuberculosis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 185 Shilpa Sharma, Ashish Minocha, and Devendra K. Gupta

19

Pyomyositis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 201 Emmanuel A. Ameh, Lohfa B. Chirdan, John W. Fitzwater, and Mike Ganey

20

Omphalitis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 209 Mairo Adamu Bugaje, Merrill McHoney, Emmanuel A. Ameh, and Kokila Lakhoo

21

Necrotizing Fasciitis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 219 Jacob N. Legbo, Emmanuel A. Ameh, and Nathan Michael Novotny

22

Hematogenous Osteomyelitis and Septic Arthritis . . . . . . . . . . . . . . . . . . . . . . . . . . . 229 Donald E. Meier, Bankole S. Rouma, and Adrienne R. Socci

23

Parasitic Infestation of Surgical Importance in Children . . . . . . . . . . . . . . . . . . . . . 241 U. E. Usang, Kokila Lakhoo, and Iftikhar Ahmad Jan

24

HIV/AIDS and the Pediatric Surgeon . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 257 Moherndran Archary and Kokila Lakhoo

III Trauma 25

Pediatric Trauma: Epidemiology, Prevention, and Control . . . . . . . . . . . . . . . . . . . 269 Barclay T. Stewart and Francis A. Abantanga

26

Pediatric Injury Scoring and Trauma Registry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 279 Francis A. Abantanga, Daniel L. Lodwick, and Benedict C. Nwomeh

27

Initial Assessment and Resuscitation of the Trauma Patient . . . . . . . . . . . . . . . . . 291 Joseph J. Lopez, Francis A. Abantanga, and Rajan K. Thakkar

28

Thoracic Trauma . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 303 A. B. (Sebastian) van As, Haiko K. Jahn, and Benedict C. Nwomeh

29

Abdominal Trauma . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 315 Iyore A. James, Dani Gonzalez, Emmanuel A. Ameh, Lohfa B. Chirdan, Barbara Gaines, and Benedict C. Nwomeh

30

Craniocerebral and Spinal Trauma . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 323 Muhammad Raji Mahmud and Bello Bala Shehu

31

Urogenital and Perineal Trauma . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 339 Lohfa B. Chirdan and Ronald S. Sutherland

32

Musculoskeletal Trauma . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 351 Jonathan I. Groner, Rajan K. Thakkar, and Michael O. Ogirima

IX Contents

33

Burns . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 361 Courtney Pisano, Edith Terna-Yawe, Peter Nthumba, Rajan K. Thakkar, and Renata Fabia

34

Injuries from Child Abuse . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 375 A. B. (Sebastian) van As, Dorothy V. Rocourt, and Benedict C. Nwomeh

35

Birth Injuries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 385 Barrett P. Cromeens, Auwal M. Abubakar, and Brian D. Kenney

IV

Head and Neck

36

Neck: Cysts, Sinuses, and Fistulas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 395 James O. Adeniran, Jonathan Durell, and Kokila Lakhoo

37

Lymphadenopathy in African Children . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 405 C. Sher-Locketz, Sam W. Moore, and Ralf-Bodo Troebs

38

Sternomastoid Tumour of Infancy and Congenital Muscular Torticollis . . . . 419 Lukman O. Abdur-Rahman and Brian H. Cameron

39

Salivary Gland Diseases in Children and Adolescents . . . . . . . . . . . . . . . . . . . . . . . . 431 Sunday Olusegun Ajike, Hemanshoo Thakkar, and Kokila Lakhoo

40

Thyroid and Parathyroid Glands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 447 Abdulrasheed A. Nasir, Emmanuel A. Ameh, and Ashley Ridout

V Thorax 41

Laryngoscopy, Bronchoscopy and Oesophagoscopy . . . . . . . . . . . . . . . . . . . . . . . . . 463 Bip Nandi, V. T. Joseph, and Michael Laschat

42

Pediatric Upper Airway Obstruction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 475 Andrew P. Freeland, John Kimario, and Bip Nandi

43

Tracheomalacia . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 485 D. P. Drake and A. Durward

44

Congenital Cystic Lung Lesions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 495 Jonathan Durell, Yona Ringo, and Kokila Lakhoo

45

Congenital Diaphragmatic Hernia and Diaphragmatic Eventration . . . . . . . . 503 Merrill McHoney and Kokila Lakhoo

46

Pleural Effusion and Empyema . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 515 Francis Aba Uba, Eric S. Borgstein, and Donald E. Meier

47

Lung Abscess . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 523 Jonathan Karpelowsky and Kokila Lakhoo

48

Oesophageal Atresia . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 527 Peter Beale, Jerome Loveland, and Kokila Lakhoo

X Contents

49

Gastro-Oesophageal Reflux Disease . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 535 Merrill McHoney and Zaitun Bokhary

50

Achalasia . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 549 George G. Youngson and Lohfa B. Chirdan

51

Corrosive Ingestion and Esophageal Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . 555 Sameh Abdel Hay, Hesham Soliman El Safoury, and Kokila Lakhoo

52

Aerodigestive Foreign Bodies in Children . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 565 Neetu Kumar, Ashish Minocha, and David Msuya

53

Chest Wall Deformities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 571 Michael Singh and Dakshesh Parikh

54

Mediastinal Masses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 583 Jonathan Karpelowsky, Jonathan Durell, and Kokila Lakhoo

55

Chylothorax . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 589 Andrew Grieve, Jonathan Durell, Jean-Martin Laberge, and Kokila Lakhoo

VI

Abdominal Wall

56

Exomphalos and Gastroschisis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 597 Iyekeoretin Evbuomwan, Jonathan Durell, Kokila Lakhoo, and Abdelbasit E. Ali

57

Disorders of the Umbilicus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 605 Jean Heuric Rakotomalala and Dan Poenaru

58

Inguinal and Femoral Hernias and Hydroceles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 615 Francis A. Abantanga and Kokila Lakhoo

VII Stomach, Duodenum, and Small Intestines 59

Infantile Hypertrophic Pyloric Stenosis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 631 Lohfa B. Chirdan, Emmanuel A. Ameh, and Amy Hughes-Thomas

60

Peptic Ulcer Disease in Children . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 639 Oludayo Adedapo Sowande and Jennifer H. Aldrink

61

Neonatal Intestinal Obstruction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 645 Daniel Sidler, Miliard Debrew, and Kokila Lakhoo

62

Duodenal Atresia and Stenosis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 655 Felicitas Eckoldt-Wolke, Afua A. J. Hesse, and Sanjay Krishnaswami

63

Intestinal Atresia and Stenosis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 663 A. J. W. Millar, Sharon Cox, John R. Gosche, and Kokila Lakhoo

64

Vitelline Duct Anomalies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 671 Bankole S. Rouma and Kokila Lakhoo

XI Contents

65

Intestinal Malrotation and Midgut Volvulus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 679 Omolara M. Williams, Jacob K. Olson, and Brian D. Kenney

66

Gastrointestinal Duplications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 687 Joseph Drews, Apeksha Dave, Benedict C. Nwomeh, Justina O. Seyi-Olajide, Auwal M. Abubakar, and Ralf-Bodo Troebs

67

Meconium Ileus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 697 Kejal Shah, Joseph Drews, Felicitas Eckoldt-Wolke, Auwal M. Abubakar, Benedict C. Nwomeh, and Justina O. Seyi-Olajide

68

Intussusception . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 705 Francis A. Abantanga, Afua A. J. Hesse, and Kokila Lakhoo

69

Miscellaneous Causes of Intestinal Obstruction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 719 Lohfa B. Chirdan and Sanjay Krishnaswami

70

Necrotizing Enterocolitis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 727 Marion Arnold, Samuel W. Moore, and Evan P. Nadler

71

Short Bowel Syndrome . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 747 Alice Mears, Kokila Lakhoo, and Alastair J. W. Millar

72

Gastrointestinal Stomas in Children . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 755 Ekene A. Onwuka, Osarumwense D. Osifo, and Benedict C. Nwomeh

VIII Colon, Rectum, and Anus 73

Colonic Atresia . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 769 A. J. W. Millar, Sharon Cox, and Kokila Lakhoo

74

Appendicitis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 775 Berous Behrouz Banieghbal and Kokila Lakhoo

75

Inflammatory Bowel Disease . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 781 Hugh W. Grant, Astor Rodrigues, and Atonasio Taela

76

Hirschsprung’s Disease . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 789 Sam W. Moore and Essam A. Elhalaby

77

Anorectal Malformations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 803 Afua A. J. Hesse, Donald E. Meier, and Victor Kobby Etwire

78

Polyps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 817 Chris Westgarth-Taylor and Kokila Lakhoo

79

Other Anorectal Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 827 John Chinda, Emmanuel A. Ameh, and Kokila Lakhoo

XII Contents

IX

Hepatobiliary System, Pancreas, and Spleen

80

Obstructive Jaundice . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 837 Francis Aba Uba, Mohammed Abdel-Latif, Alaa F. Hamza, and Evelyn G. P. Ong

81

Biliary Atresia . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 845 Katrine Lofberg, John Sekabira, and Sanjay Krishnaswami

82

Choledochal Cyst . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 857 Nasser Kakembo, Donald E. Meier, and Tamara N. Fitzgerald

83

Cholelithiasis (Gallstones) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 865 Bankole S. Rouma, Donald E. Meier, and Tamara N. Fitzgerald

84

Annular Pancreas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 873 Ashley Ridout, Jonathan Durell, and Kokila Lakhoo

85

Pancreatitis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 877 Lucinda Tullie and Kokila Lakhoo

86

Spleen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 887 Johanna R. Askegard-Giesmann, Bankole S. Rouma, and Brian D. Kenney

87

Portal Hypertension . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 897 Alastair J. W. Millar and Evelyn G. P. Ong

Volume II X

Pediatric Urology

88

Cystic Diseases of the Kidney . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 909 Rodrigo L. P. Romao, Martin Situma, Osarumwense David Osifo, and Edward Hannon

89

Congenital Ureteropelvic Junction Stenosis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 915 Justin Howlett, Chris Heinick, John Lazarus, and Ceri Elbourne

90

Ureteric Duplications and Ureterocoeles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 925 Phyllis Kisa, V. T. Joseph, Keren Sloan, and Adam B. Hittelman

91

Vesicoureteric Reflux . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 933 Sarah Howles, Hemanshoo Thakkar, Zaitun Bokhary, and Kokila Lakhoo

92

Bladder Exstrophy and Epispadias Complex . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 941 William Appeadu-Mensah, Piet Hoebeke, and Safwat S. Andrawes

93

Posterior Urethral Valves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 965 Charlotte Q. Wu, Edmond Ntaganda, Adam B. Hittelman, Stefan Wolke, and Christopher C. Amah

94

Hypospadias . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 973 Phyllis Kisa, Catherine De Vries, Ahmed T. Hadidi, Philemon E. Okoro, and Gillian M. Barker

XIII Contents

95

Male Circumcision . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 997 Daniel Sidler, Christopher Bode, and Ashish P. Desai

96

Phimosis, Meatal Stenosis and Paraphimosis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1011 Merrill McHoney, Hemanshoo Thakkar, Kokila Lakhoo, and Yona Ringo

97

Urolithiasis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1019 Philip M. Mshelbwala, Jessica Ng, and Adam B. Hittelman

98

Undescended Testis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1027 John Lazarus, Safwat S. Andrawes, Sarah Ullrich, and Doruk Ozgediz

99

Disorders of Sex Development . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1037 Katrine Lofberg, Kathleen van Leeuwen, Mohammed Abdel-Latif, Andrew R. Ross, and Essam A. Elhalaby

100

Bladder Outlet Obstruction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1053 Lukman O. Abdur-Rahman and Rowena Hitchcock

101

Acute Scrotum . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1067 William Appeadu-Mensah and Ashish P. Desai

102

Prune Belly Syndrome . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1075 Phyllis Kisa and Gillian M. Barker

XI Tumours 103

Kidney Tumours . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1085 Sebastian O. Ekenze, George G. Youngson, and Kokila Lakhoo

104

Teratomas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1093 Shilpa Sharma, Daniel C. Aronson, Devendra K. Gupta, and Kokila Lakhoo

105

Lymphoma and the Pediatric Surgeon . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1103 Larry Hadley and Kokila Lakhoo

106

Neuroblastoma . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1111 Larry Hadley, Jonathan Durell, and Kokila Lakhoo

107

Malignant Soft Tissue Tumors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1119 Sam W. Moore and Kokila Lakhoo

108

Liver Tumours: The African Perspective . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1137 Daniel C. Aronson, Graeme Pitcher, V. T. Joseph, and Kokila Lakhoo

109

Primary Bone Tumours . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1153 Andrew Wainwright, Kant Shah, and Kokila Lakhoo

110

Brain and Spinal Cord Tumours . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1163 Bello Bala Shehu, Muhammad Raji Mahmud, Saurabh Sinha, and Jayaratnam Jayamohan

XIV Contents

XII Vascular System 111

Lymphangiomas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1177 Justina O. Seyi-Olajide, Louise Caouette-Laberge, Emmanuel A. Ameh, and Jean-Martin Laberge

112

Haemangiomas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1195 Nicos Marathovouniotis and Abdulrasheed Ibrahim

113

Arteriovenous Malformations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1207 Phuong D. Nguyen and Do Thi Ngoc Linh

114

Unilateral Limb Enlargement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1215 Charles F. M. Evans, Snigdha M. Reddy, and Jacob N. Legbo

XIII Pediatric Gynecology 115

Hydrometrocolpos . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1227 Bankole S. Rouma, Julia B. Finkelstein, Jennifer H. Aldrink, and Howard B. Ginsburg

116

Müllerian Duct Anomalies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1237 Nkeiruka Ameh, Gbolahan Adesiyun, Ismael E. Elhalaby, Hesham M. Abdelkade, and Essam A. Elhalaby

117

Labial Adhesions/Agglutination . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1249 Adesoji O. Ademuyiwa, Safwat S. Andrawes, Modupe Odelola, and Kokila Lakhoo

118

Ovarian Lesions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1253 Lauren Damle, Rachel Webman, Adekunle O. Oguntayo, and Evan P. Nadler

XIV Surgical Rehabilitation 119

Disability and Rehabilitation: General Concepts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1267 Norgrove Penny

120

Neurodisability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1275 Wegoye Emmanuel and Dan Poenaru

121

Common Pediatric Orthopaedic Diseases . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1291 Norgrove Penny, Tewodros Tilahun Zerfu, and Paul J. Moroz

122

Plastic and Reconstructive Surgery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1331 Peter Nthumba

123

Pediatric Burn Surgery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1353 Heinz Rode and Roux Martinez

XV Contents

XV Special Topics 124

Minimal Access Surgery in Pediatric Patients . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1369 Mikael Petrosyan, Evan P. Nadler, Nathan R. Zilbert, and Daniel Sidler

125

Prenatal Diagnosis and Fetal Therapy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1379 Kokila Lakhoo

126

Conjoined and Parasitic Twins . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1391 Alastair J. W. Millar

127

Otorhinolaryngology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1401 Frank Agada, Manali Amin, Andrew Coatesworth, and Assem Shayah

128

Pediatric Transplantation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1417 Jerome Loveland, Hesham M. Abdelkader, and Khaled M. El-Asmar Al

129

Pediatric Surgery Education in Sub-Saharan Africa . . . . . . . . . . . . . . . . . . . . . . . . . . 1433 Katrine Lofberg, Patricia Shinondo, and Maurice Mars

Contributors Francis A. Abantanga  School of Medicine & Health Sciences, Department of Surgery, University for Development Studies, Tamale, Ghana [email protected] Hesham M. Abdelkade  Department of Pediatric Surgery, Ain Shams University, Cairo, Egypt Mohammed  Abdel-Latif  Faculty Helwan University, Cairo, Egypt [email protected]

of

Medicine,

Department

of

Pediatric

Surgery,

Lukman O. Abdur-Rahman  Division of Pediatric Surgery, Department of Surgery, University of Ilorin and University of Ilorin Teaching Hospital, Ilorin, Nigeria [email protected] Auwal M. Abubakar  Division of Pediatric Surgery, Federal Medical Centre, Yola, Nigeria [email protected] Adesoji O. Ademuyiwa  Pediatric Surgery Unit, Department of Surgery, Faculty of Clinical Sciences, College of Medicine, University of Lagos, Lagos, Nigeria [email protected] James O. Adeniran  Division of Pediatric Surgery, Department of Surgery, University of Ilorin and University of Ilorin Teaching Hospital Ilorin, Ilorin, Nigeria Gbolahan  Adesiyun  Department of Obstetrics & Gynecology, Ahmadu Bello University Teaching Hospital, Zaria, Nigeria [email protected] Frank Agada  Department of ENT, Head and Neck Surgery, York Hospital, York, UK [email protected] Sunday  Olusegun  Ajike  Department of Dental Surgery, Ahmadu Bello Univerity, Zaria, Nigeria [email protected] Jennifer  H.  Aldrink  Department of Pediatric Surgery, Nationwide Children’s Hospital, Columbus, OH, USA [email protected] Abdelbasit E. Ali  Department of Pediatric Surgery, King Saud Medical City, Riyadh, KSA Associate Professor, Faculty of Medicine, University of Khartoum, Khartoum, Sudan [email protected] Christopher C. Amah  Sub Department of Pediatric Surgery, University of Nigeria, Nsukka and University of Nigeria Teaching Hospital, Enugu, Nigeria Emmanuel A. Ameh  Division of Pediatric Surgery, Department of Surgery, National ­Hospital, Abuja, Nigeria [email protected] Nkeiruka  Ameh  Department of Obstetrics & Gynecology, Ahmadu Bello University and Ahmadu Bello University Teaching Hospital, Zaria, Nigeria [email protected]

XVII Contributors

Manali Amin  Department of Otolaryngology and Communication Disorders, Children’s Hospital Boston, Boston, MA, USA Safwat S. Andrawes  Gertrude Children’s Hospital, Nairobi, Kenya William  Appeadu-Mensah  Department of Surgery, University of Ghana Medical School, Korle-bu Teaching Hospital, Accra, Ghana [email protected] Moherndran Archary  Pediatric Infectious Diseases Unit, King Edward VIII Hospital, University of KwaZulu Natal, Durban, South Africa [email protected] Marion  Arnold  Red Cross War Memorial Children’s Hospital & University of Cape Town, Cape Town, South Africa [email protected] Daniel C. Aronson  Department of Pediatric Surgery, University Children’s Hospital Zürich, Zürich, Switzerland [email protected] Johanna  R.  Askegard-Giesmann  Department of Pediatric Surgery, Nationwide Children’s Hospital, Columbus, OH, USA Berous  Behrouz  Banieghbal  Division of Pediatric Surgery, Stellenbosch Univeristy, Cape Town, South Africa [email protected] Immaculate W. K. Barasa  AIC Kijabe Hospital, Kijabe, Kenya Gillian M. Barker  Department of Pediatric Urology/Womens and Childrens Health, University Children’s Hospital, Uppsala University, Uppsala, Sweden Peter Beale  University of the Witwatersrand, Johannesburg, South Africa Christopher Bode  Department of Surgery, University of Lagos and Lagos University Teaching Hospital, Lagos, Nigeria [email protected] Zaitun Bokhary  Muhimbili National Hospital, Dar es Salaam, Tanzania Laura  A.  Boomer  Children’s Hospital of Richmond at Virginia Commonwealth University, Richmond, VA, USA [email protected] Eric S. Borgstein  College of Medicine, University of Malawi, Queen Elizabeth Central Hospital, Blantyre, Malawi [email protected], [email protected] Mairo Adamu Bugaje  Department of Pediatrics, Ahmadu Bello University and Ahmadu Bello ­University Teaching Hospital, Zaria, Nigeria Brian H. Cameron  McMaster University and McMaster Children’s Hospital, Hamilton, ON, Canada

XVIII Contributors

Louise  Caouette-Laberge  Pediatric Plastic Surgery, Hospital Sainte-Justine, Universite de Montreal, Montreal, QC, Canada John  Chinda  Division of Pediatric Surgery, University of Abuja and University of Abuja Teaching Hospital, Abuja, Nigeria Lohfa B. Chirdan  Pediatric Surgery Unit, Department of Surgery, University of Jos & Jos University Teaching Hospital, Jos, Nigeria [email protected] Andrew  Coatesworth  Department of ENT, Head and Neck Surgery, York Hospital, York, UK Sharon  Cox  Division of Pediatric Surgery, University of Cape Town and Red Cross War Memorial ­Children’s Hospital, Cape Town, South Africa [email protected] Barrett P. Cromeens  Department of General Pediatric Surgery, Nationwide Children’s Hospital, Columbus, OH, USA [email protected] Stephanie Cruz  New York, NY, USA Olamide O. Dairo  Nationwide Childrens Hospital, Anesthesia and Pain Medicine, Columbus, OH, USA [email protected] Lauren  Damle  The George Washington University School of Medicine & Health Sciences Children’s National Health System, Washington, DC, USA Apeksha Dave  Ohio University College of Medicine, OH, USA [email protected] Catherine De Vries  Department of Surgery, University of Utah, Salt Lake City, UT, USA Miliard Debrew  Black Lion Hospital, Addis Ababa University, Addis Ababa, Ethiopia Ashish P. Desai  Department of Pediatric Surgery, King’s College Hospital, London, UK Molly  C.  Dienhart  Pediatric Gastroenterology, Hepatology and Nutrition, The Ohio State University/Nationwide Children’s Hospital, Columbus, OH, USA [email protected] D. P. Drake  Evelina London Children’s Hospital, London, UK [email protected] Joseph Drews  Department of Pediatric Surgery, Nationwide Children’s Hospital, Columbus, Ohio, USA [email protected] Jonathan Durell  Children’s Hospital Oxford and University of Oxford, Oxford, UK [email protected] A. Durward  Evelina London Children’s Hospital, London, UK Felicitas Eckoldt-Wolke  Jena, Germany

XIX Contributors

Stella  A.  Eguma  Department of Anaesthesia, University of Calabar Teaching Hospital, ­Calabar, Nigeria Sebastian O. Ekenze  Department of Pediatric Surgery, University of Nigeria and University of Nigeria Teaching Hospital, Enugu, Nigeria Hesham Soliman El Safoury  Department of Pediatric Surgery, Ain Shams University, Cairo, Egypt Khaled M. El-Asmar Al  Department of Pediatric Surgery, Ain Shams University, Cairo, Egypt Ceri  Elbourne  Department of Pediatric Urology and Pediatric Surgery, The Royal London Hospital, London, UK Essam A. Elhalaby  Department of Pediatric Surgery, Faculty of Medicine, Tanta University Hospital, Tanta University, Tanta, Egypt [email protected], [email protected] Ismael E. Elhalaby  Department of Pediatric Surgery, Tanta University Hospital, Tanta, Egypt Wegoye Emmanuel  Medical Director, CURE Uganda, Mbale, Uganda Victor Kobby Etwire  Pediatric Surgery Unit, Department Of Surgery, Korle-Bu Teaching Hospital, Accra, Ghana Charles F. M. Evans  Department of Pediatric Surgery, Oxford Chilren’s Hospital, Oxford, UK Iyekeoretin  Evbuomwan  Unit of Pediatric Surgery, Department of Surgery, University of Benin ­Teaching Hospital, Benin City, Nigeria [email protected] Renata Fabia  Department of Pediatric Surgery, Nationwide Children’s Hospital, Columbus, OH, USA [email protected] Julia B. Finkelstein  Department of Urology, Boston Children’s Hospital, Boston, MA, USA Tamara N. Fitzgerald  Division of Pediatric Surgery, Duke University, Durham, NC, USA John W. Fitzwater  Texas Tech University Health Sciences Center, Lubbock, TX, USA Kathryn Ford  Department of Pediatric Surgery, Oxford University Hospitals, Oxford, UK Andrew P. Freeland  John Radcliffe Hospital, Oxford, UK Barbara Gaines  University of Pittsburgh School of Medicine, Trauma and Injury Prevention, Pittsburgh, PA, USA Mike Ganey  Tenwek Hospital, Tenwek, Kenya Loma Linda University School of Medicine, Loma Linda, CA, USA Howard B. Ginsburg  Division of Pediatric Surgery, Department of Surgery, New York University School of Medicine, Hassenfeld Children’s Hospital at NYU Langone, New York, NY, USA

XX Contributors

Dani  Gonzalez  Division of Pediatric Surgery, Nationwide Children’s Hospital, Columbus, OH, USA John  R.  Gosche  Division of Pediatric Surgery, University of Nevada School of Medicine, Las Vegas, NV, USA [email protected], [email protected] Hugh W. Grant  John Radcliffe Hospital, Oxford, UK [email protected] Andrew  Grieve  University of the Witwatersrand, Department of Pediatric Surgery, Johannesburg, South Africa [email protected] Jonathan I. Groner  Division of Pediatric Surgery, Nationwide Children’s Hospital, Columbus, OH, USA Devendra K. Gupta  Department of Pediatric Surgery, All India Institute of Medical Sciences, New Delhi, India Ahmed  T.  Hadidi  Hypospadias Center, Dept. at Offenbach Hospital, Emma Hospital, Seligenstadt, Germany Larry Hadley  Department of Pediatric Surgery, Nelson Mandela School of Medicine and College of Health Sciences, University of Kwa-Zulu Natal Durban South Africa, Durban, South Africa Alaa F. Hamza  Department of Pediatric Surgery, Ain Shams University, Cairo, Egypt Edward Hannon  Department of Pediatric Surgery, Oxford Children’s Hospital, Oxford, UK Erik N. Hansen  Department of Surgery, University of Texas-Southwestern Medical Center, & Children’s Medical Center of Dallas, Dallas, TX, USA Department of Pediatric Surgery, Vanderbilt University Medical Center, Nashville, TN, USA [email protected] Sameh  Abdel  Hay  Department of Pediatric Surgery, Faculty of Medicine, Ain Shams ­University, Cairo, Egypt [email protected] Chris  Heinick  Pediatric Surgeon, Klinik für Kinderchirurgie der Friedrich-Schiller­ Universität, Jena, Germany Afua  A.  J.  Hesse  Disciplines of Anatomy and Surgery, Accra College of Medicine, Accra, Ghana Department of Surgery, University of Ghana School of Medicine and Dentistry, Accra, Ghana Department of Surgery, Korle-Bu Teaching Hospital and the University of Ghana Medical School (UGMS), Accra, Ghana [email protected] Rowena Hitchcock  Oxford Children’s Hospital, Oxford, UK Adam  B.  Hittelman  Department of Urology and Pediatrics, Yale School of Medicine, New Haven, CT, USA Alaa F. Hamza deceased

XXI Contributors

Piet Hoebeke  Division of Pediatric Urology, Department of Urology, Ghent University Hospital, Ghent University, Ghent, Belgium Paris Hosseini  Oxford University Hospitals, Oxford, UK Sarah Howles  Department of Pediatric Surgery, Children’s Hospital Oxford, Oxford, UK [email protected] Justin Howlett  University of Cape Town, Cape Town, South Africa [email protected] Amy  Hughes-Thomas  Department of Pediatric Surgery, King’s College Hospital, London, UK [email protected] Abdulrasheed Ibrahim  Division of Plastic and Reconstructive Surgery, Ahmadu Bello University & Ahmadu Bello University Teaching Hospital, Zaria, Nigeria [email protected] Haiko K. Jahn  Royal Belfast Hospital for Sick Children, Belfast, UK Iyore A. James  Surgical Specialist of Charlotte, PA, Charlotte, North Carolina, USA Iftikhar Ahmad Jan  Mafraq Hospital, Abu Dhabi, UAE The Children’s Hospital, PIMS Islamabad, Islamabad, Pakistan [email protected] Jayaratnam  Jayamohan  Department of Pediatric Neurosurgery, John Radcliffe Hospital, Oxford, UK [email protected] V. T. Joseph  Department of Pediatric Surgery, John Radcliffe Hospital, Oxford, UK Oxford University Hospitals, Oxford, UK Nasser Kakembo  Department of Surgery, Makerere University School of Medicine, Kampala, Uganda [email protected] Jonathan Karpelowsky  Department of Pediatric Surgery, Red Cross War Memorial Children’s Hospital, Cape Town, South Africa Brian D. Kenney  Department of General Pediatric Surgery, Nationwide Children’s Hospital, Columbus, OH, USA [email protected] Sundeep Keswani  Department of Pediatric Surgery, Texas Children’s Hospital, Houston, TX, USA John Kimario  Department of Surgery, Muhimbili National Hospital, Dar es Salaam, Tanzania Phyllis Kisa  Pediatric Surgical Unit, Department of Surgery, Makerere University College of Health ­Sciences, Kampala, Uganda [email protected] Sharon Kling  Department of Pediatric Surgery, Stellenbosch University, Cape Town, South Africa

XXII Contributors

Sanjay Krishnaswami  Division of Pediatric Surgery, Oregon Health and Science University, Portland, OR, USA [email protected] Neetu Kumar  Department of Urology, Great Ormond Street Hospital for Children, London, UK Chun-Sui Kwok  Department of Pediatric Surgery, Children’s Hospital Oxford, Oxford, UK J.  Matthew  Kynes  Department of Pediatric Surgery, Vanderbilt University Medical Center, Vanderbilt Children’s Hospital, Nashville, TN, USA Jean-Martin Laberge  Division of Pediatric General Surgery, The Montreal Children’s Hospital of the McGill University Health Center, Montreal, QC, Canada Kokila Lakhoo  University of Oxford and Oxford University Hospitals, Oxford, UK [email protected], [email protected] Michael  Laschat  Division of Pediatric Anaesthesia, Children’s Hospital Colonge, Colonge, Germany Patricio Lau  Department of General Surgery, Baylor College of Medicine, Houston, TX, USA John Lazarus  Department of Pediatric Urology, Red Cross War Memorial Hospital, University of Cape town, Cape Town, South Africa Jacob N. Legbo  Division of Plastic & Reconstructive Surgery, Department of Surgery, Usmanu Danfodiyo University & Usmanu Danfodiyo University Teaching Hospital, Sokoto, Nigeria [email protected] Do Thi Ngoc Linh  Viet Duc Hospital, Hanoi, Vietnam Daniel L. Lodwick  The Ohio State University, Columbus, OH, USA Katrine Lofberg  Division of Pediatric Surgery, Randall Children’s Hospital at Legacy Emanuel, Portland, OR, USA Joseph J. Lopez  Westchester Medical Center – New York Medical College, Valhalla, NY, USA Jerome Loveland  Department of Pediatric Surgery, School of Clinical Medicine, University of the ­Witwatersrand, Johannesburg, South Africa [email protected] Muhammad Raji Mahmud  Division of Neurosurgery, Ahmadu Bello University and Ahmadu Bello University Teaching Hospital, Zaria, Nigeria [email protected] Nicos Marathovouniotis  Department of Pediatric Surgery and Pediatric Urology, Children’s Hospital of Cologne, Cologne, Germany Maurice Mars  University of KwaZulu-Natal, Durban, South Africa [email protected] Roux Martinez  Department of Pediatric Surgery, Red Cross War Memorial Children’s Hospital, ­University of Cape Town, Cape Town, South Africa

XXIII Contributors

Merrill McHoney  Department of Pediatric Surgery, Royal Hospital for Sick Children, Edinburgh, UK [email protected] Alice Mears  Department of Pediatric Surgery, Oxford Children’s Hospital and University of Oxford, Oxford, UK [email protected] Donald E. Meier  Division of Pediatric Surgery, Paul L Foster School of Medicine, Texas Tech University Health Sciences Center, El Paso, TX, USA [email protected] Alastair  J. W.  Millar  Emeritus Professor of Pediatric Surgery, University of Cape Town and Red Cross War Memorial Children’s Hospital, Cape Town, South Africa [email protected] Ashish Minocha  Jenny Lind Children’s Department, Norfolk & Norwich University Hospital, Norwich, UK [email protected] Samuel W. Moore  Division of Pediatric Surgery, University of Stellenbosch, Tygerberg, South Africa [email protected] Paul J. Moroz  Shriners Hospitals for Children, Honolulu, HI, USA Associate Clinical Professor, Department of Surgery, John A. Burns School of Medicine, University of Hawaii, Honolulu, HI, USA Philip  M.  Mshelbwala  Division of Pediatric Surgery, Department of Surgery, University of Abuja ­Teaching Hospital, Abuja, Nigeria [email protected] David Msuya  Kilimanjaro Christian Medical Centre and Tumaini University, Moshi, Tanzania Evan  P.  Nadler  The George Washington University School of Medicine & Health Sciences, Washington, DC, USA Department of Pediatric Surgery, Children’s National Health System, Washington, DC, USA [email protected] Bip  Nandi  Consultant Pediatric Surgeon Kamuzu Central Hospital, Lilongwe, Malawi and Associate Professor or Surgery, Baylor College of Medicine, Texas, USA [email protected] Abdulrasheed A. Nasir  Division of Pediatric Surgery, University of Ilorin and University of Ilorin Teaching Hospital, Ilorin, Nigeria [email protected] Mark  W.  Newton  Department of Anaesthesiology, Vanderbilt University Medical Centre, Nashville, TN, USA Department of Anaesthesiology, AIC Kijabe Hospital, Kijabe, Kenya [email protected] Jessica Ng  Department of Pediatric Surgery, Oxford University Hospitals, Oxford, UK

XXIV Contributors

Phuong  D.  Nguyen  Department of Pediatric Surgery, Children’s Hospital of Philadelphia, Philadelphia, PA, USA [email protected] Nathan  Michael  Novotny  Department of Pediatric Surgery, Beaumont Children’s Oakland University William Beaumont School of ­Medicine, Royal Oak, MI, USA Jordan University of Science and Technology, Irbid, Jordan Edmond Ntaganda  Yale School of Medicine, New Haven, CT, USA Peter  Nthumba  Department of Plastic and Reconstructive Surgery, AIC Kijabe Hospital, Kijabe, Kenya Benedict  C.  Nwomeh  Department of Surgery, The Ohio State University Wexner Medical Center, Columbus, OH, USA Division of Pediatric Surgery,Nationwide Children’s Hospital, , Columbus, OH, USA [email protected], [email protected] J. Ken Muma Nyagetuba  AIC-Kijabe Hospital, Kijabe, Kenya [email protected] Modupe Odelola  Princess Royal University Hospital, Kent, UK Michael O. Ogirima  Department of Orthopaedic and Trauma Surgery, Ahmadu Bello University and Ahmadu Bello University Teaching Hospital, Zaria, Nigeria G.  Olufemi  Ogunrinde  Department of Pediatrics, Faculty of Clinical Sciences, College of Health ­Sciences, Ahmadu Bello University, Zaria, Nigeria [email protected], [email protected] Adekunle  O.  Oguntayo  Department of Obstetric & Gynecology, Ahmadu Bello University Teaching H ­ ospital, Zaria, Nigeria Philemon E. Okoro  Pediatric Surgery Unit, Department of Surgery, University of Port Harcourt Teaching Hospital, Port Harcourt, River State, Nigeria Jacob K. Olson  Nationwide Children’s Hospital, Columbus, OH, USA [email protected] Oluyinka  O.  Olutoye  Department of Pediatric Surgery, Nationawide Children’s Hospital, Columbus, OH, USA Peter F. Omonzejele  Department of Philosophy, University of Benin, Benin City, Nigeria Richard Onalo  Department of Pediatrics, Faculty of Clinical Sciences, College of Health Sciences, U ­ niversity of Abuja, Abuja, Nigeria [email protected], [email protected] Evelyn  G.  P.  Ong  The Liver Unit, Birmingham Women’s and Children’s NHS Foundation Trust, Birmingham, UK [email protected] Ekene A. Onwuka  Department of Surgery, The Ohio State University Wexner Medical Center, Columbus, OH, USA [email protected]

XXV Contributors

Osarumwense David Osifo  Division of Pediatric Surgery, University of Benign Teaching Hospital, Benin City, Nigeria [email protected] Doruk Ozgediz  Department of Surgery, University of California, San Francisco, CA, USA [email protected] Dakshesh  Parikh  Birmingham Women’s and Children’s Hospital NHS Trust, Birmingham, UK [email protected] Norgrove  Penny  Branch for International Surgical Care, University of British Columbia, Victoria, BC, Canada Mikael  Petrosyan  Surgery and Pediatrics, Children’s National Health System, Washington, DC, USA [email protected] Courtney Pisano  Department of Pediatric Surgery, Nationwide Children’s Hospital, Columbus, OH, USA Graeme  Pitcher  Department of Surgery, University of the Witwatersrand and Chris Hani Baragwanath Hospital, Johannesburg, South Africa Dan Poenaru  Department of Pediatric Surgery, Montreal Children’s Hospital, Montreal, Québec, Canada [email protected] Jean Heuric Rakotomalala  SALFA Hospital, Manambaro, Madagascar Snigdha M. Reddy  Department of Pediatric Surgery, Oxford University Hospital, Oxford, UK Ashley Ridout  Oxford Deanery School of Surgery, Oxford, UK [email protected] Yona Ringo  Pediatric Surgery Unit, Muhimbili National Hospital, Dar es Salaam, Tanzania [email protected] Dorothy V. Rocourt  Department of Surgery, Division of Pediatric Surgery, The Pennsylvania State University, College of Medicine, Penn State Children’s Hospital, Hershey, PA, USA Heinz Rode  Department of Pediatric Surgery, Red Cross War Memorial Children’s Hospital, University of Cape Town, Cape Town, South Africa [email protected] Astor Rodrigues  Department of Pediatric Surgery, John Radcliffe Hospital, Oxford, UK Rodrigo L. P. Romao  Division of Pediatric Urology, IWK Health Centre; Department of Urology, Dalhousie University, Halifax, NS, Canada Andrew R. Ross  Department of Pediatric Surgery, John Radcliffe Hospital, Oxford, UK David H. Rothstein  Department of Pediatric Surgery, John R. Oishei Children’s Hospital and University at Buffalo, Buffalo, NY, USA

XXVI Contributors

Bankole  S.  Rouma  Department of Pediatric Surgery, University Hospital of Treichville, Abidjan, Côte d’Ivoire CHU de Treichvill, Abidjan, Côte d’Ivoire [email protected] John  Sekabira  Department of Surgery, Makerere University, Mulago Hospital, Kampala, Uganda Justina  O.  Seyi-Olajide  Pediatric Surgery Unit, Department of Surgery, Lagos University Teaching Hospital, Lagos, Nigeria [email protected] Kant Shah  Department of Pediatric Surgery, Hinduja Childrens Hospital, Mumbai, India Kejal Shah  Columbus, OH, USA [email protected] Shilpa Sharma  Department of Pediatric Surgery, All India Institute of Medical Sciences, New Delhi, India [email protected] Assem Shayah  Department of ENT, Head and Neck Surgery, York Hospital, York, UK Bello Bala Shehu  Neurosurgery Unit, Department of Surgery, Usmanu Danfodiyo University, Sokoto, and Federal University, Birnin Kebbi, Nigeria [email protected] C.  Sher-Locketz  Department of Anatomical Pathology and National Health Laboratories, University of Stellenbosch, Stellenbosch, South Africa Patricia Shinondo  Department of Surgery, Lusaka National Hospital, Lusaka, Zambia Daniel Sidler  Division of Pediatric Surgery, Stellenbosch University and Tygerberg Children’s Hospital, Cape Town, South Africa [email protected] Michael Singh  Birmingham Women’s and Children’s Hospital NHS Trust, Birmingham, UK [email protected], [email protected] Saurabh Sinha  Department of Pediatric Surgery, Sheffield Children’s Hospital, Sheffield, UK Martin  Situma  Department of Surgery, Mbarara Regional Referral Hospital, Mbarara and University of Science and Technology, Mbarara, Uganda Keren Sloan  Department of Pediatric Surgery, Oxford University Hospitals, Oxford, UK [email protected] Adrienne  R.  Socci  Department of Orthopaedics and Rehabilitation, Yale University, New Haven, CT, USA Oludayo  Adedapo  Sowande  Pediatric Surgery Unit, Department of Surgery, Obafemi Awolowo U ­ niversity/Obafemi Awolowo University Teaching Hospital, Ife, Nigeria [email protected]

XXVII Contributors

Helen Sowerbutts  Department of Pediatric Surgery, Children’s Hospital Oxford and University of Oxford, Oxford, UK Barclay T. Stewart  Department of Surgery, Harborview Medical Center, Seattle, WA, USA [email protected] Ronald S. Sutherland  Honolulu, HI, USA Atonasio Taela  Department of Surgery, Eduardo Mondlane University, Maputo Central Hospital, Maputo, Mozambique Edith Terna-Yawe  Division of Plastic and Reconstructive Surgery, National Hospital Abuja, Abuja, Nigeria Hemanshoo Thakkar  Oxford University Hospitals, Oxford, UK Rajan K. Thakkar  Department of Pediatric Surgery, Nationwide Children’s Hospital, Columbus, OH, USA Department of Pediatric Surgery, Oxford Children’s Hospital, Oxford, UK [email protected] Ralf-Bodo  Troebs  Marienhospital Herne, St. Elisabeth Gruppe, Ruhr-Universität Bochum, Herne, Germany Department Klinik für Kinderchirurgie, Universitätsklinikum Marienhospital Herne, Herne, Germany [email protected] Lucinda Tullie  Department of Pediatric Surgery, Children’s Hospital Oxford, Oxford, UK [email protected] Francis  Aba  Uba  Pediatric Surgery Unit, Department of Surgery, University of Jos/Jos ­University Teaching Hospital, Jos, Nigeria [email protected] Sarah Ullrich  Department of Surgery, Yale University Hospital,, New Haven, CT, USA U. E. Usang  Pediatric Surgery Unit, Department of Surgery, University of Calabar, and University of Calabar Teaching Hospital, Calabar, Nigeria A.  B.  (Sebastian)  van  As  Department of Pediatric Surgery, University of Cape Town, Cape Town, South Africa [email protected] Kathleen  van  Leeuwen  Department of Pediatric Surgery, Phoenix Children’s Hospital, Phoenix, AZ, USA Andrew Wainwright  Department of Pediatric Surgery, Oxford Children’s Hospital, Oxford, UK Rachel Webman  Division of Trauma and Burn Surgery, Department of General and Thoracic Surgery, Children’s National Medical Center, Washington, DC, USA

XXVIII Contributors

Chris Westgarth-Taylor  Department of Pediatric Surgery, Chris Hani Baragwanath Academic Hospital, University of the Witwatersrand, Johannesburg, South Africa Omolara M. Williams  Pediatric Surgery Unit, Department of Surgery, Lagos State University College of Medicine, Lagos, Nigeria [email protected] Stefan Wolke  Department of Pediatric Urology, Clinic of Pediatric Surgery, Jena University Hospital Friedrich Schiller, University of Jena, Jena, Germany Charlotte Q. Wu  Division of Pediatric Urology, Children’s Healthcare of Atlanta; Emory University School of Medicine, Atlanta, GA, USA [email protected] George G. Youngson  Department of Pediatric Surgery, University of Aberdeen, Royal Aberdeen C ­ hildren’s Hospital, Aberdeen, Scotland, UK [email protected] Tewodros  Tilahun  Zerfu  Pediatric Orthopedic Surgeon, CURE International Hospital, Addis Ababa, Ethiopia [email protected] Nathan R. Zilbert  Department of Surgery, University of Toronto, Toronto, ON, Canada

1

Basic Principles Contents Chapter 1 Pediatric Surgery Specialty and Its Relevance to Africa – 3 Ekene A. Onwuka, Philip M. Mshelbwala, and Benedict C. Nwomeh Chapter 2 Neonatal Physiology and Transport – 15 Larry Hadley and Kokila Lakhoo Chapter 3

Respiratory Physiology and Support – 25 John R. Gosche, Mark W. Newton, and Laura A. Boomer

Chapter 4

Cardiovascular Physiology and Support – 33 Mark W. Newton, John R. Gosche, and Laura A. Boomer

Chapter 5 Fluids and Electrolyte Therapy in the Pediatric Surgical Patient – 43 Mark W. Newton, Chun-Sui Kwok, and Kokila Lakhoo Chapter 6

Nutrition Support – 55 Molly C. Dienhart and Afua A. J. Hesse

Chapter 7

Haemoglobinopathies – 63 G. Olufemi Ogunrinde and Richard Onalo

Chapter 8

Wound Healing – 73 Patricio Lau, Stephanie Cruz, Sundeep Keswani, and Oluyinka O. Olutoye

Chapter 9

Vascular Access in Children – 89 J. Ken Muma Nyagetuba and Erik N. Hansen

Chapter 10 Anaesthesia and Perioperative Care – 101 Mark Newton, Olamide O. Dairo, and Stella A. Eguma Chapter 11 Pain Management – 115 Helen Sowerbutts, J. Matthew Kynes, Jonathan Durell, and Kokila Lakhoo

I

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Chapter 12 Intensive Care – 123 Immaculate W. K. Barasa and Erik N. Hansen Chapter 13 Ethics of Pediatric Surgery in Africa – 137 Daniel Sidler, Sharon Kling, Benedict C. Nwomeh, and Peter F. Omonzejele Chapter 14 Psychological Issues in Pediatric Surgery – 147 Paris Hosseini, Kathryn Ford, and Kokila Lakhoo

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Pediatric Surgery Specialty and Its Relevance to Africa Ekene A. Onwuka, Philip M. Mshelbwala, and Benedict C. Nwomeh Contents 1.1

Introduction – 4

1.2

Historical Background – 5

1.3

Burden of Surgical Diseases in African Children – 6

1.4

Barriers to Effective Pediatric Surgical Care – 7

1.4.1 1.4.2 1.4.3 1.4.4

S ocioeconomic and Cultural Factors – 7 Poor Health-Care Facilities – 8 Referral and Transport – 8 Shortage of Trained Workforce – 8

1.5

Recommendations – 9

1.5.1 1.5.2 1.5.3 1.5.4 1.5.5

T raining – 9 Support for Nonsurgical Personnel – 10 Research – 10 Leadership – 10 Advocacy – 11

1.6

Evidence-Based Research – 11 References – 12

© Springer Nature Switzerland AG 2020 E.A. Ameh et al. (eds.), Pediatric Surgery, https://doi.org/10.1007/978-3-030-41724-6_1

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1.1  Introduction

..      Table 1.1 (continued)

In Africa, children constitute half the population [1], and therefore, much effort is devoted to the prevention and treatment of childhood diseases. Emphasis is placed on diseases that cause the greatest morbidity and mortality, such as communicable diseases (especially human immunodeficiency virus/acquired immune deficiency syndrome (HIV/AIDS), malaria, and respiratory infections), maternal and perinatal conditions, and nutritional deficiencies [2]. In many African countries, scarce health-care resources have been concentrated on the provision of immunisation, HIV control, malaria eradication, and other public health concerns. As a result, diseases for which surgical intervention offers the only hope for prevention, palliation, or cure usually do not come within the radar of health policy makers. Additionally, surgical care has traditionally been viewed as being expensive and therefore not a good use of the limited resources available. Given that surgical diseases have not been considered significant health- care problems in Africa, the pediatric surgical specialty has not received the attention it deserves [3]. Despite varying degrees of subspecialisation in North American hospitals [4], pediatric surgeons are often described as the only true general surgeons [5], and this is especially the case in Africa, where pediatric subspecialisation is rare in orthopaedics, urology, otolaryngology, thoracic surgery, plastic surgery, and neurosurgery. The pediatric surgeon in Africa, therefore, provides cost-effective care for children in these impoverished countries, often crossing the traditional boundaries of the specialty. A detailed list of pediatric surgical diagnoses encountered in an urban hospital in Africa is provided in . Table  1.1. Unaccounted for in most studies are those children for whom treatment is inaccessible due to distance, cost, or lack of qualified personnel. Bickler et  al. analysed all pediatric visits at the main urban hospital in Banjul, The Gambia, and  

..      Table 1.1  Surgical conditions seen among children (n = 1200) treated at elective surgery at Komfo Anokye Teaching Hospital, Kumasi, Ghana Disease entity

Number of children

Percent of total (%)

Inguinal hernia

511

42.58

Hydrocele

100

8.33

Undescended testis

93

7.75

Umbilical hernia

63

5.25

Disease entity

Number of children

Percent of total (%)

Polydactyly

51

4.25

Neoplasm

44

3.67

Anorectal malformations

34

2.83

Superficial cysts

30

2.50

Uncircumcised penis

28

2.33

Hirschsprung’s disease

27

2.25

Enlarged lymph nodes

26

2.17

Cystic hygroma/cystic lymphangioma

21

1.75

Haemangioma

15

1.25

Skin tags

15

1.25

Rectal polyp

14

1.17

Oesophageal stricture

10

0.83

Wilms’ tumour

9

0.75

Thyroglossal cysts

9

0.75

Rectovaginal fistulas

8

0.67

Sacrococcygeal teratoma

8

0.67

Syndactyly

7

0.58

Epigastric hernia

5

0.42

Incisional hernia

5

0.42

Spina bifida

5

0.42

Ganglion

4

0.33

Ambiguous genitalia

3

0.25

Anal stenosis

3

0.25

Meatal stenosis

3

0.25

Enterocutaneous fistula

3

0.25

Hypersplenism with splenomegaly

3

0.25

Popliteal cyst

3

0.25

Congenital hypertrophic pyloric stenosis

2

0.17

Branchial sinus/cyst

2

0.17

Patent urachus

2

0.17

Urethral caruncle

2

0.17

32

2.67

1200

100.00

Miscellaneous Total

Source: Adapted from Abantanga and Amaning [76]

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5 Pediatric Surgery Specialty and Its Relevance to Africa

..      Fig. 1.1  Estimated risk of requiring surgical care in a pediatric population living in Banjul, The Gambia. Cumulative risk was estimated by using age-specific incidences. (Source: Adapted from Bickler and Rode [6])

100 All surgical conditions Injuries 80

Congenital anomalies Surgical anomalies Miscellaneous

% affected

60

40

20

0 0

3

6

9

12

15

Age (years)

estimated the incidence of pediatric surgical problems to be 543 per 10,000 children aged 0–14 years, of which 46% required surgical procedures. Using age-specific incidences, the authors estimated the cumulative risk for all surgical conditions at 85.4% by age 15  years (. Fig. 1.1) [6, 7]. The sparse epidemiologic data available point to the significant burden of surgical disease and has contributed to the increasing recognition of the value of surgery as a component of basic healthcare. Recent publications such as Disease Control Priorities, third edition (DCP3) [8] and Lancet Commission on Global Surgery [9] report have underscored the importance of surgery as a means of providing both preventive and curative treatment to patients in need and promoting economic growth [9]. As such, it is imperative that pediatric surgical care be integrated into a comprehensive strategy to reduce the burden of disease in Africa.  

1.2  Historical Background

The practice of pediatric surgery as a specialty in Africa has its roots in South Africa during the 1920s with pediatric surgeons from the Hospital for Sick Children, Great Ormond Street, London, as pioneers [10]. In the late 1940s and 1950s, the first pediatric surgical unit was established at Groote Schuur Hospital in Cape Town by Jan H.  Louw, and since then, the practice of pediatric surgery in Africa has become firmly established. Several national and regional organisations have been

formed to promote the practice of pediatric surgery. In 1994, the Pan African Pediatric Surgical Association (PAPSA) was formed, which held its inaugural meeting in Nairobi, Kenya, in March 1995. In 2004, the African Journal of Pediatric Surgery (AJPS) was founded by Francis Aba Uba. This publication has already achieved listing in Medline, thus removing a major obstacle to the growth of the specialty. In the past five decades, many Africans have trained in pediatric surgery, both overseas and recently in indigenous residency programmes. Pediatric surgery divisions now exist in several departments of surgery, many of which participate in the education of medical students and general surgery residents. In a few centres, subspecialty training in pediatric surgery has been established with a formalised curriculum. Regulation and oversight of pediatric surgery training have been carefully maintained by professional bodies that administer the examination and certification required for credentialing as a subspecialist. Currently, examination and certification in pediatric surgery have been organised on a regional basis. In South Africa, surgeons who have completed general surgery training and an additional 2 years of subspecialty training may take the specialty examination in pediatric surgery offered by the Colleges of Medicine of South Africa. In West Africa, surgeons become eligible for examination and certification in pediatric surgery after a minimum of 30 months of general surgery training and a further 24  months of subspecialty training under the aegis of the West African College of Surgeons [11].

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African surgeons have made significant contributions to the practice of pediatric surgery and have also championed the development of the specialty locally. Many pediatric surgeons with roots in Africa have achieved local and international recognition for their clinical, research, and leadership roles. As a prime example, the dominant hypothesis on the aetiology of intestinal atresia was the outcome of a series of experiments performed by Jan Louw and Christiaan Barnard at the Red Cross Children’s Hospital in Cape Town. This seminal work, published in Lancet in 1955, provided direct evidence for vascular accidents as the likely mechanism in the pathogenesis of intestinal atresia during fetal development. Louw was honoured with the prestigious Sir Denis Browne Gold Medal by the British Association of Pediatric Surgeons (BAPS) in 1980. The 2004 honouree for this award was another South African, Sir Lewis Spitz, who rose to the Nuffield Chair of Pediatric Surgery at the Hospital for Sick Children, Great Ormond Street, London. Recently, Sid Cywes was accorded the honorary fellowship of the American College of Surgeons. Additionally, Donald Nuss, who developed the minimally invasive repair for pectus excavatum, began his training in Africa. 1.3  Burden of Surgical Diseases in African

Children

With only 11% of the world’s population, Africa bears 25% of the global burden of disease. Several well-known factors, including endemic poverty, poor literacy rates, civil conflicts, and corrupt political leadership, contribute to the overwhelming burden of childhood disease in low- and middle-income countries. Although comprehensive data on the incidence of pediatric surgical conditions in Africa is lacking, available information suggests that trauma, congenital anomalies, and surgical infections are common [12]. Yet, the focus on the prevention and treatment of infectious diseases has often led to the neglect of trauma and other surgical disease as important factors in the overall disease burden in children from these regions. Despite the perceived high costs and limited availability of a trained workforce and equipment, surgery is often an essential and integral part of basic healthcare, as in cases of treatment of injuries, urinary retention, and inhaled foreign bodies, or preventive, as in the case of elective hernia repair [6]. In fact, Gosselin et al. performed a cost-effectiveness analysis to evaluate the costs and disability-adjusted life years (DALYs) saved by the provision of surgical services to children in a rural ­hospital in Sierra Leone, and the positive effect was comparable to that of other public health interventions [13]. Other studies document the costeffectiveness of treating various congenital anomalies

such as inguinal hernia [14], hydrocephalus [15], and cleft lip and palate [16]. Failure to recognise the importance of surgical treatment has led to neglect by both governmental and donor agencies. An estimated 234 million major surgical procedures are performed worldwide annually [17], which is seven times the number of persons infected with HIV, but only 3.5% of these are performed in the poorest nations, many of which are in Africa [18]. The view of surgical disease as being relatively unimportant has been amplified by a lack of accurate epidemiological studies. However, emerging data highlight the need to re-­examine conventional thinking. One report from a rural hospital in Malumfashi, Nigeria, and another from a large urban hospital in Banjul, The Gambia, showed that pediatric surgical cases account for 6.6% and 11.3% of all pediatric admissions, respectively [18, 19]. In both studies, 80–90% of all pediatric surgical admissions were due to congenital anomalies, surgical infections, and trauma. While congenital malformations account for 25 million DALYs worldwide, data specific to Africa is limited by the absence of population-based data. In 2013, Wu et al. performed the first study documenting the prevalence of selected surgical anomalies among children in Kenya. The overall prevalence of congenital malformations was 6.3 per 1000 children, which amounted to 54–1000 DALYs per 1000 children [20]. . Figure  1.2 shows the prevalence and mean burden of disease of selected malformations. The most common neonatal conditions reported in the literature over the past 20 years are intestinal atresia, abdominal wall defects, anorectal malformations, Hirschsprung’s disease, necrotising enterocolitis, and volvulus neonatorum [21]. Mortality has been highest (>50%) in emergency neonatal surgeries involving bowel perforation, bowel resection, congenital diaphragmatic hernia, oesophageal atresia, and ruptured omphalocele or gastroschisis. Major documented challenges to care include delayed presentation, inadequate facilities, dearth of trained support personnel, and absence of intensive care [21]. A study in Kampala, Uganda, estimates that only 3.5% of the need for neonatal surgery is met by the health system [22]. Trauma is also an important cause of morbidity, mortality, and disability in African children. According to estimates by the World Health Organization (WHO), injuries account for 950,000 deaths every year in children under 18 years. 830,000 of these are classified as ‘unintentional’, with road traffic injuries and drowning accounting for half the cases of unintentional injuries. Injury is the leading cause of death for children over 9  years old, and 95% of these deaths occur in low- or middleincome countries [23]. Deen et al. have projected that the relative contributions of injuries and non-­communicable diseases to the childhood disease burden in developing countries will increase from 28% in 1990 to 45% by 2020 [24]. Reports from urban and suburban West Africa indi 

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7 Pediatric Surgery Specialty and Its Relevance to Africa

..      Fig. 1.2  Prevalence and mean burden of disease from selected congenital malformations in Kenya. Burden of disease is the disability and premature death that would exist in a population without any surgical care. (Source: Adapted from Wu et al. [20])

40

3.5 Female DALYs Male DALYs 3

35

Prevalence

30 2.5 Prevalence per 1,000

25

20

DALYs

2

1.5 15 1

10

0.5

0

5

s nu ea t ra

r fo

pe

Im

d

ad

Bl

tro

xs

e er

y ph C

lef

e lat pa / p t li

cate that trauma is responsible for about 9% of attendance in a children’s emergency room and is the most common cause (47%) of pediatric admissions [25, 26]. Even in rural Africa, where studies are few, there are indications that trauma is an important cause of pediatric admissions to health facilities [19, 27]. Systemisation of trauma care improves patient outcomes, but adult trauma systems are relatively non-existent in Africa, let alone pediatric systems. There is an urgent need to invest in such systems with a focus on infrastructure development, training specialised personnel, forming regionalised trauma centres, and establishing a trauma registry to generate relevant and timely data on causes, severity and outcome of pediatric injury, research on adaptable injury control measures, and adequate funding by governmental and nongovernmental agencies [28]. 1.4  Barriers to Effective Pediatric

Surgical Care

The most significant obstacle to the development of pediatric surgical services in Africa has traditionally been the lack of interest shown by the various governments as well as the nongovernmental organisations (NGOs) [29]. The role of the NGOs is quite crucial

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because their contribution to health-care expenditures in many African countries is substantial and occasionally exceeds the health budget of national governments [2]. These NGOs, especially the UN agencies (World Bank, WHO, and the United Nations Children’s Fund (UNICEF)) and private foundations (e.g. The Bill & Melinda Gates Foundation), exert even greater influence because they often set the agenda for health-care priorities of many developing countries. 1.4.1  Socioeconomic and Cultural Factors

Africa remains a predominantly illiterate and poor continent, with the majority of the population surviving on US $2 daily [30]. Due to the lack of health insurance, out-of-pocket private expenditure on health care is the norm. Therefore, healthcare is in direct competition with the basic subsistence needs for food, shelter, and clothing. An estimated 150 million people face financial catastrophe expenditure – defined as an expenditure of more than 40% of non-food household expenditure or 10% of overall household expenditure [31]  – every year as a result of direct out-of-pocket costs of medical care [9, 32]. Treatment of surgical disease accounts for 32.8 million, or 22%, of these cases. This number only reflects direct costs

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of care, but when including other costs associated with obtaining care such as transportation, lodging, or food, an additional 48 million cases of catastrophic expenditure occur each year, bringing the number to 81.2 million annual cases attributable to accessing surgical care [31]. Several global health and developmental organisations have therefore supported the prioritisation of universal health coverage [33–35] as part of the global health agenda, the WHO, and the World Bank are targeting 100% financial protection from catastrophic expenditure from out-of-pocket payments by 2030 [9, 33]. One success story comes from Sierra Leone, where in April 2003, the Ministry of Health and Sanitation began offering free health care to pregnant women, new mothers, and children under 5 years old [36]. In the month before free healthcare, an average of 170,000 children received care from hospital facilities each month. This number doubled to 340,000 in the months after free healthcare. Similar success has been seen when looking specifically at pediatric surgical conditions. Connaught Hospital, the main tertiary care referral centre in the capital city, Freetown, saw a more than 1000% increase in operative pediatric surgery cases, from 20 in 2009 to 100 in the first 6 months of 2011 [37]. The complexity of the operations performed increased, as did the number of pediatric burn admissions, pediatric nonoperative trauma cases, and complex postpartum cases. Even if families can afford to pay for care, they may be unaware that surgical treatment is feasible or available for a variety of disabling, disfiguring, or life-­threatening congenital or acquired conditions. A persistent cultural attitude towards congenital anomalies continues to hinder access to corrective surgery. Congenital anomalies may be ascribed to supernatural causes or the curse of the gods. Fortunately, egregious behaviour such as the sacrifice of malformed babies has been largely eliminated, although reluctance to seek treatment persists. 1.4.2  Poor Health-Care Facilities

Currently, most pediatric surgeons in Africa practice in large urban hospitals that principally serve adult patients. Many of these centres are overcrowded, poorly funded, and lack facilities such as a dedicated pediatric ward, pediatric emergency room, neonatal intensive care unit (NICU), pediatric radiology, and pediatric pathology, which are considered basic requirements for a sustainable pediatric surgery practice. Where these facilities exist, they are often poorly equipped and are frequently operated by doctors who have not undergone dedicated pediatric training. The lack of pediatric anaesthesia has caused some surgeons to rely on local anaesthesia or staged procedures for complex cases [29, 38]. Jan H.  Louw established the first pediatric surgery unit in Southern Africa at the Groote Schuur Hospital

in Cape Town in 1948; this became a full department in 1952 [10]. Since then, several other centres have emerged in South Africa where medical care in general and pediatric surgery services in particular have advanced to a level comparable with many Western countries. The practice of pediatric surgery as a specialty has now been established in several other African countries, but unfortunately the majority of these are plagued with poor facilities and dysfunctional health care systems. Until 2013, the only dedicated children’s hospital in sub-­Saharan Africa was the Red Cross War Memorial Hospital, Rondebosch, South Africa. Here, pediatric surgeons enjoy facilities in a major clinical and research pediatric centre recognised both regionally and internationally [10]. It has since been joined by the KwaZulu-­Natal Children’s Hospital in Durban, South Africa, which was originally opened in 1931 as the first dedicated children’s hospital in Africa but closed during apartheid due to conflicts between its mission to serve children of all races and its location in an affluent white neighbourhood. Most recently, the Nelson Mandela Children’s Hospital, a 200-bed tertiary care facility, opened in Johannesburg, South Africa. It is equipped with a Ronald McDonald House Charities to provide accommodations for families traveling from abroad, as well as resources to make it a centre for research and training around specialised pediatric care [39]. These advanced pediatric facilities have played a pivotal role in the training of pediatric surgeons from across the continent. 1.4.3  Referral and Transport

Poor obstetric services limit the ability to perform prenatal diagnosis and planned delivery for infants with severe congenital anomalies, as is routinely obtained in most developed countries. Many pregnant women do not receive antenatal care, and sometimes the only obstetric service available is delivery by untrained traditional birth attendants (TBAs) [29, 40]. Untrained TBAs are unable to recognise congenital anomalies for which early surgical treatment is essential to prevent early death. Such conditions include oesophageal atresia, intestinal atresia, and congenital diaphragmatic hernia. Even when referrals to appropriate health care facilities are made, the poor condition of rural roads and inadequate transport facilities often lead to neonatal loss in transit or presentation in a debilitated and decompensated physiological state. 1.4.4  Shortage of Trained Workforce

Despite the increasing number of medical schools in Africa, the number of doctors practicing on the continent remains grossly inadequate. In Nigeria, about 80 practicing pediatric surgeons cater to a pediatric

9 Pediatric Surgery Specialty and Its Relevance to Africa

population (less than 18  years of age) that exceeds 80 million. This gives a ratio of one pediatric surgeon to about one million children (compared to 1:100,000  in North America). The few pediatric surgeons available are often overworked and are largely inaccessible to the overwhelming majority of the populace. The void is filled at best by non-specialist surgeons or general practitioners and at worst by quacks and traditional healers. The reasons for the shortage of trained pediatric surgeons are not far-­fetched. Lack of facilities and supporting personnel has limited the capacity to train pediatric surgeons locally, and opportunities for training overseas have been severely curtailed. To compound this problem, pediatric surgery is not a popular choice of career for aspiring surgeons. This situation has been attributed to the heavy workload, a frustrating lack of facilities, and poor compensation. Under these conditions, it is difficult to attract young surgeons with the promise of a rewarding and satisfying career. The endemic brain drain has also played a role in depleting the number of practicing surgeons, many going overseas for further training but never returning to their home countries. As many as 47 sub-Saharan African countries have lost over 60% of their doctor workforce to migration [41]. Push factors stimulating emigration include civil instability and personal health risks. Pull factors include higher income, job satisfaction, and career development outside of sub-­Saharan Africa [42– 44]. The workforce shortage affects the entire spectrum of pediatric care, including nursing, radiology, anaesthesiology, and pathology. 1.5  Recommendations

The relevance of pediatric surgery in Africa and other developing regions is no longer in doubt [45]. However, if the impact of the pediatric surgical practice as part of essential health care to children is to be felt, then a major paradigm shift is needed. Some of the ideas presented here have been drawn from the seven-point strategy advocated by Bickler et al., which should be required reading for all pediatric surgeons and health policy makers in Africa (see . Table 1.2) [7, 12].  

1.5.1  Training

Wider exposure of medical students and surgeons in training to pediatric surgery would likely generate more interest in the specialty. Trainees could, however, develop an aversion to the specialty if a positive mentoring environment is not provided. The tendency towards exploitative and even brutal treatment of surgical residents is an unfortunate legacy of Halstedian training. Recognition of the deleterious effect of such an abusive

..      Table 1.2  Strategies for improving pediatric surgery care in Africa 1

Define communities’ health needs with input from the communities

2

Demonstrate the need for pediatric surgical services

3

Foster community participation

4

Start with what is available and build on existing services

5

Integrate preventive and curative services

6

Facilitate ongoing training

7

Remain goal directed within available resources

Source: Adapted from Bickler et al. [12]

environment to surgical education has been the impetus behind the resident work-hour limitations now in force in most Western countries. Unfortunately, the old habits remain the norm in much of Africa and may be a major obstacle to recruiting bright young talent into the specialty. The quality of pediatric surgery training has been adversely affected by the lack of adequate facilities and limited exposure to current techniques [46]. Increasing global partnerships provide an opportunity to improve human and material capacity [18]. While short-term mission trips have been valuable in filling certain treatment gaps [47–49], increasing emphasis is being placed on long-term collaboration to build relationships and increase workforce capacity. Such partnerships could involve exchange programmes with colleagues and trainees from developed countries and also intraregional collaboration that could be incorporated into local residency training programmes [50]. One report describes a global health partnership between the United Kingdom and Tanzania that resulted in the training of six pediatric surgeons and the separation of the adult and pediatric surgery services at the Tanzanian hospital. Physicians from the United Kingdom benefited by being able to experience practice in lower resource settings, thereby bringing cost-effective strategies back to their own institutions. Tantamount to the success of this program was the need of the host country to extend an invitation, followed by the mutual agreement of a working plan resulting in the exchange of skills with mutual trust and friendship [51]. Partnerships should benefit both parties, and mutual respect will need to be emphasised as more collaborations are set up between teaching universities in LMIC and more developed nations [52–55]. Importantly, while the benefit of such programs to visiting scholars is well documented, continued assessment of the host institutions perceptions is needed to ensure robust partnerships and identify potential challenges in collaborative research and ethical dilemmas [56].

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Surgeons in high-income countries have taken an increased interest in opportunities to volunteer, and trainees are increasingly interested in serving in resource-­poor areas to enhance training and collaboration. Several professional surgical societies have recently developed global surgery initiatives that provide training opportunities for African surgeons, including the American College of Surgeons (ACS) [57], the American Pediatric Surgical Association (APSA) [58], and the Association for Academic Surgery (AAS) [59]. The Global Pediatric Surgery Network (GPSN) launched a website in 2010 that was designed to be a central clearinghouse for volunteering opportunities. The GPSN collaborative brings together international teams of globally minded pediatric surgeons to identify priority areas, increase communication on global development goals, and identify common interest to serve as platforms for collaboration. Their focus is on increasing workforces in host institutions through networking, education, research, and advocacy while also avoiding depletion of trainees from LMICs [60]. Skills transfer can be achieved by using novel methods, such as telesimulation and telementoring, where mentors or experts in other parts of the world can offer advice or direct access to real-time surgical procedures being performed in resource-poor hospitals [61]. Telesimulation can be used for consultation [62], discussion of clinical cases, or for training in advanced skills such as laparoscopic surgery [61]. Recorded seminars may play a role in areas where implementation of telesimulation is restricted by costs involved and low bandwith [63]. 1.5.2  Support for Nonsurgical Personnel

Given the dearth of trained pediatric surgeons, it is inevitable that the vast majority of children with pediatric surgical conditions will seek care from adult surgeons, non-surgeon physicians, and nonphysician health professionals. Many newborn infants die needlessly due to lack of referral for surgical care. Building pediatric surgery workforces will take time, and some have proposed task shifting as a cost-effective means of caring for patients during the interim period. One study found that training and deploying nonphysician technicians, such as técnicos de cirurgia, to provide obstetric surgery was three times more cost-effective than training and deploying physicians [64]. Nonphysician practitioners are also more likely than physicians to stay in their hometowns and rural areas and less likely to emigrate to other countries, thereby increasing access in these underserved regions [65]. However, there is significant concern about the appropriateness and safety of delegating nonphysicians, even non-surgeons, to the operative care of children with sometimes complex congenital

malformations. At the launch of the Lancet Commission on Global Surgery, task sharing (not task shifting) was an important topic of discussion, with an emphasis on there being a specialist provider available to ensure quality and accountability [66]. Task sharing depends on a team approach that may include nonphysician providers but with appropriate training, careful definition of scope of procedures, and a mechanism for supervision and oversight. Utilisation of nonphysician or non-surgeon providers, in whichever capacity, will be enhanced by educational programmes that improve their ability to recognise common pediatric surgical conditions, and improve early triage and referral, particularly for life-­ threatening conditions. 1.5.3  Research

African pediatric surgeons should become more involved in clinical and basic science research in order to improve the care of their patients and generate awareness for their work. The most fundamental task here is to collect, analyse, and publish data reflecting local experience with childhood surgical disease. Also important is research related to the burden of surgical disease and workforce capacity in Africa, since this data will serve as a powerful advocacy tool when trying to assess the resources needed. Sitkin et al. suggest the following research priorities for LMICs: (1) epidemiology, prevalence, and incidence of disease, (2) pediatric surgical capacity at all levels of the health system, (3) optimised quantitative metrics of disease burden, (4) models for the integration of pediatric surgical services within existing child health initiatives, (5) cost-effectiveness data, and (6) researching innovative strategies to align marketing and advocacy [67]. Survey tools have been developed to objectively assess the burden of both pediatric surgical disease [68] and capacity and to better plan and allocate resources for care in LMICs. One example is the pediatric PIPES (PediPIPES) survey, based on the previously described surgeons overseas personnel, infrastructure, procedure, equipment and supplies (PIPES) [69, 70] survey but modified where appropriate to be relevant to pediatric surgical care [71]. A solid, data-supported understanding of the problem at hand will lead to more focused and effective development of interventions. 1.5.4  Leadership

Although specialty organisations for pediatric surgeons are essential, it is important to be connected to the wider field of surgery. This can be achieved by ensuring that pediatric surgery remains an integral component

11 Pediatric Surgery Specialty and Its Relevance to Africa

of the surgery department educational activities as well as morbidity and mortality conferences. Presentation of research work should not be limited to specialty meetings; rather, a strong pediatric surgery presence needs to be maintained in national and regional conferences involving surgeons of different specialties. Furthermore, pediatric surgeons should seek every opportunity to network and collaborate with pediatricians by organising joint educational activities and participating in pediatric meetings. This will give pediatric surgeons visibility among their peers and facilitate public recognition of their vital role in the provision of child health care. The surgical section of the American Academy of Pediatrics is the prototype for such collaboration [72]. Pediatric surgeons should strive to achieve leadership positions in their surgery departments as well as in umbrella national and regional surgical organisations to ensure that the interests of children and the specialty are well represented. Finally, pediatric surgeons in Africa should maintain strong collaborative relationships with colleagues in other parts of the world at personal, professional, and organisational levels. The quality, reputation, and international recognition of local specialty certification would be enhanced by recruiting examiners from other parts of the world to participate at the various local certification examinations [72].

1.5.5  Advocacy

Recently, there has been a growing recognition of the importance of surgical care in the effort to reduce the global burden of disease [73]. The WHO has developed the Global Initiative for Emergency and Essential Surgical Care (GIEESC), which currently includes pilot projects in 17 countries, of which 8 are in Africa. WHO’s legislative arm, the World Health Assembly, recently passed a resolution in which several countries pledged to prioritise the strengthening of emergency and essential surgical care and anaesthesia as a component of universal health coverage [74]. Several groups, such as the Lancet Commission on Global Surgery and the Global Alliance for Surgical, Obstetric, Trauma and Anaesthesia Care (G4 Alliance), have been formed with the goal of using research and advocacy to advance the global health agenda. As the momentum continues to grow and surgical care receives more attention, the hope is that more resources will be devoted to pediatric surgical care in LMICs. 1.6  Evidence-Based Research

. Table  1.3 presents a study evaluating the burden of pediatric trauma-related disease at one hospital in Malawi.  

..      Table 1.3  Evidence-based research Title

Epidemiology of pediatric injury in Malawi: Burden of disease and implications for prevention [75]

Authors

Michelle M. Kiser, Jonathan C. Samuel, Sean E. Mclean, Arturo P. Muyco, Bruce A. Cairns, Anthony G. Charles

Institution

University of North Carolina, Chapel Hill, NC, USA; Kamuzu Central Hospital, Lilongwe, Malawi

Reference

Int J Surg. 2012;10(10):611–617

Problem

To utilise a comprehensive database to describe the epidemiology of pediatric injuries at a tertiary hospital in Malawi

Study design

Retrospective analysis of prospectively collected data on patients presenting to the emergency department at Kamuzu Central Hospital in Lilongwe, Malawi, for treatment of injuries from 2008 to 2010 (n = 23,625). A subset of pediatric patients (n = 7233) underwent cross-sectional analysis to examine demographics, injury environment, timing, and mechanisms

Length of study

2 years

Results

Pediatric patients age 0–16 comprised 30.6% of all trauma patients. The most common injury was falls (43%), followed by burns (11.1%) and pedestrian road traffic injuries (9.7%). After logistic regression, predictors of fall included male gender, home setting, and rainy season, whereas predictors of burn included female gender, age 0–5 yrs., home setting, and cold season. Predictors of pedestrian injury included age 6–10 yrs., female, and roadside setting

Complications

None

Outcome/effect

This study revealed patterns of injury based upon age, gender, location, and season

Conclusions

These results may prove useful to stakeholders in injury prevention for designing, evaluating, and implementing programs to improve public safety in children in Malawi and similar resource-poor nations

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Key Summary Points 1. Surgical care has traditionally been viewed as being expensive and not a good use of the limited resources available, but recent research has shown the importance of surgery as a means of providing both preventive and curative treatment to patients in need and also promoting economic growth. 2. Mortality in emergency neonatal surgeries involving bowel perforation, bowel resection, congenital diaphragmatic hernia, oesophageal atresia, and ruptured omphalocele or gastroschisis is very high. Major documented challenges to care include delayed presentation, inadequate facilities, dearth of trained support personnel, and absence of intensive care. 3. Injury is the leading cause of death for children over 9 years old, and 95% of these deaths occur in low- or middle-income countries. 4. The most significant obstacle to the development of pediatric surgical services in Africa has traditionally been the lack of interest shown by the various governments as well as the nongovernmental organisations. 5. Due to the lack of health insurance, out-of-pocket private expenditure on health care is the norm. Therefore, health care is in direct competition with the basic subsistence needs for food, shelter, and clothing. 6. Several global health and developmental organisations have supported the prioritisation of universal health coverage as part of the global health agenda. 7. Most pediatric surgeons in Africa practice in large urban hospitals that principally serve adult patients are overcrowded, poorly funded, and lack facilities such as a dedicated pediatric ward, pediatric emergency room, neonatal intensive care unit (NICU), pediatric radiology, and pediatric pathology, elements considered to be basic requirements for a sustainable pediatric surgery practice. 8. There is a paucity of trained pediatric surgeons due to the lack of facilities and supporting personnel with the capacity to train pediatric surgeons locally, poor compensation, and the availability of robust oversea training experiences. 9. Wider exposure of medical students and surgeons in training to pediatric surgery would likely generate more interest in the specialty. 10. Training and deploying nonphysician technicians, such as técnicos de cirurgia, may be a cost-effective way to provide care while the surgical workforce is expanded.

11. African pediatric surgeons should become more involved in clinical and basic science research in order to improve the care of their patients and generate awareness for their work. 12. Pediatric surgeons in Africa should maintain strong collaborative relationships with colleagues in other parts of the world at personal, professional, and organisational levels.

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61. Okrainec A, Henao O, Azzie G.  Telesimulation: an effective method for teaching the fundamentals of laparoscopic surgery in resource-restricted countries. Surg Endosc. 2010;24: 417–22. 62. Bertani A, Launay F, Candoni P, Mathieu L, Rongieras F, Chauvin F.  Teleconsultation in paediatric orthopaedics in Djibouti: evaluation of response performance. Orthop Traumatol Surg Res (Elsevier Masson SAS). 2012;98:803–7. 63. Hadley GP, Mars M. e-Education in Pediatric Surgery: a role for recorded seminars in areas of low bandwidth in sub-Saharan Africa. Pediatr Surg Int. 2011;27:407–10. 64. Kruk ME, Pereira C, Vaz F, Bergström S, Galea S.  Economic evaluation of surgically trained assistant medical officers in performing major obstetric surgery in Mozambique. BJOG. 2007;114:1253–60. 65. Mock CN, Donkor P, Gawande A, Jamison DT, Kruk ME, Debas HT, et  al. Essential surgery: key messages from disease control priorities, 3rd edition. Lancet (Elsevier Ltd). 2015;1: 1–11. 66. Mullan Z. The surgery spring. Lancet Glob Heal. 2015;3:e297. 67. Sitkin NA, Ozgediz D, Donkor P, Farmer DL. Congenital anomalies in low- and middle-income countries: the unborn child of global surgery. World J Surg. 2015;39:36–40. 68. Groen RS, Samai M, Petroze RT, Kamara TB, Cassidy LD, Joharifard S, et  al. Household survey in Sierra Leone reveals high prevalence of surgical conditions in children. World J Surg. 2013;37:1220–6.

69. Groen RS, Kamara TB, Dixon-Cole R, Kwon S, Kingham TP, Kushner AL. A tool and index to assess surgical capacity in low income countries: an initial implementation in Sierra Leone. World J Surg. 2012;36:1970–7. 70. Kushner AL, Groen RS, Kamara TB, Dixon-Cole R, Daoh KS, Kingham TP, et al. Assessment of pediatric surgery capacity at government hospitals in Sierra Leone. World J Surg. 2012;36:2554–8. 71. Okoye MT, Ameh EA, Kushner AL, Nwomeh BC. A pilot survey of pediatric surgical capacity in West Africa. World J Surg (Springer New York LLC). 2015;39:669–76. 72. Nwomeh BC, Mshelbwala PM.  Pediatric surgical specialty: how relevant to Africa? African J Paediatr Surg Medknow Publications. 2004;1:36–42. 73. Taira BR, Kelly McQueen KA, Burkle FM. Burden of surgical disease: does the literature reflect the scope of the international crisis? World J Surg. 2009;33:893–8. 74. World Health Assembly  — Essential Surgery [Internet]. [cited 2015 Dec 23]. Available from: http://www.­essentialsurgery.­com/ world-health-assembly/ 75. Kiser MM, Samuel JC, Mclean SE, Muyco AP, Cairns BA, Charles AG. Epidemiology of pediatric injury in Malawi: burden of disease and implications for prevention. Int J Surg (Elsevier Ltd). 2012;10:611–7. 76. Abantanga FA, Amaning EP.  Pediatric elective surgical conditions as seen at a referral hospital in Kumasi, Ghana. ANZ J Surg. 2002;72(12):890–2.

15

Neonatal Physiology and Transport Larry Hadley and Kokila Lakhoo Contents

2.1

Introduction – 16

2.2

Neonatal Classification – 16

2.3

Temperature Control – 17

2.4

Cardiovascular Adaptation – 18

2.5

Respiratory Adaptation – 19

2.6

Clinical Evaluation – 20

2.7

Nutrition – 20

2.7.1 2.7.2

 ypoglycaemia – 20 H Hyperglycaemia – 21

2.8

Immune Function – 21

2.9

Neonatal Transport [25, 26] – 21

2.10

Evidence-Based Research – 23 References – 24

© Springer Nature Switzerland AG 2020 E.A. Ameh et al. (eds.), Pediatric Surgery, https://doi.org/10.1007/978-3-030-41724-6_2

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2.1  Introduction

2.2  Neonatal Classification

It is perhaps trite to emphasize that the child is not merely a small adult, but nowhere is this distinction more apparent than in the neonate. The transition from intrauterine to extrauterine life requires fundamental changes in the circulatory, respiratory, metabolic, and immune functions of the newborn. When a surgical pathology is added to the mix, these essential adaptations can be compromised, leading to organ dysfunction. Single organ dysfunction is frequently the start of a cascade that rapidly results in failure of the entire organism. Thus, the emphasis in neonatal care is on the prevention of problems rather than on the management of disasters once they have occurred. In order to prevent dysfunction, it is important to recognize patients at particular risk but also to have in place general principles of care and to train nursing staff and paramedical personnel in their application. Neonatal care is a team effort. Whenever possible, the team should include the mother and other family members, if culturally appropriate [1]. Neonatal physiology is not defined by geography or politics, but our ability to recognize and respond to system dysfunction is a factor of the human and material resources available. In a developing country where scarce resources must be utilized for the maximum benefit of numerous constituencies, imaginative alternatives to standard Western care are required. It is in just this environment that maternal ill health and deficient antenatal care add to the considerable difficulties faced by neonates during the perinatal period. Many of the neonate’s survival mechanisms are installed during the third trimester of pregnancy, and preterm delivery can additionally challenge the successful transition to independent life, the difficulties being directly proportional to the degree of prematurity. Occasionally, the uterus proves to be a hostile environment for the developing foetus, and, in conjunction with obstetric colleagues, pregnancy management will need to take account of the interests of both the foetus and the mother. Certainly the antenatal recognition of surgical disease calls for skilled management of the pregnancy and delivery and provides the surgeon with an unborn patient for whom diagnosis, prognosis, investigation, and management are difficult. A few specific anomalies can be ascribed to genetic, teratogenic, or infectious causes, but the pathogenesis of most congenital malformations remains unknown. It is improbable, however, that any insult that results in a congenital abnormality will affect a single system or structure without affecting other structures that are developing at the same time. Thus, multiple abnormalities should be suspected and sought in every neonate presenting for surgery.

Neonates come in a variety of sizes and degrees of maturity. It is important to recognize risk factors in any patient presenting for surgery, but particularly so in the neonate, in whom body weight and prematurity are easily assessed and critical to defining the likely comorbidities and risk factors and help to determine appropriate management (. Fig. 2.1). Many ‘surgical’ babies are born before term and are often, in addition, small for their gestational age (SGA). These two factors include maternal infections and poor nutrition, placental insufficiency, maternal cigarette smoking, and maternal substance abuse such as drugs and alcohol. Frequently, polyhydramnios complicates a pregnancy in which the foetus has an intestinal abnormality due to the inability to ingest and recycle amniotic fluid, stimulating early labour. Such babies are therefore exposed to the risks of prematurity and its associated problems as well as the morbidity of a surgical pathology. Recognition of a neonate’s status allows prediction of potential clinical problems, allowing preventive steps to be taken. . Table  2.1 outlines the traditional risks faced by SGA and preterm infants. The risks associated with prematurity are reflected in the mortality of preterm babies without surgical disease and depend upon the degree of prematurity and body weight (. Fig. 2.2). This risk of mortality must be weighed against the available resources and the nature of the surgical problem before a decision on m ­ anagement can be taken. Such considerations are particularly germane to the practice of neonatal surgery in a developing country where both human and material resource limitations may be extreme.  

 

 

4000 LGA Birth Weight (gm)

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L. Hadley and K. Lakhoo

2000 AGA SGA

Pre-term Gestation (wks)

40 37 42 Post-term Term

..      Fig. 2.1  Neonatal classification. LGA large for gestational age, AGA average for gestational age, SGA small for gestational age

2

17 Neonatal Physiology and Transport

2.3  Temperature Control

The neonate is designed as a radiator with a large surface area relative to its mass. Heat is lost through convection, conduction, radiation, and the latent heat of evaporation of transdermal fluid loss. In the term neonate, heat loss is reduced by a layer of insulating subcutaneous fat and a thick skin that reduces transdermal fluid loss. Heat production comes from hepatic glycogenolysis

..      Table 2.1  Predictable problems in small for gestational age (SGA) and preterm average for gestational age (AGA) babies SGA

Preterm AGA

Lung

Pulmonary haemorrhage

Hyaline membrane disease

Apnoea

+

+++

Hypoglycaemia

+++

+

Hypocalcaemia

+

+++

Jaundice

+

+++

Haemoglobin

Polycythaemia

Normal

Feeding capacity

Normal

Reduced

Congenital malformations

+++

+

Mortality

+++

Depends upon gestational age

..      Fig. 2.2  Neonatal classification and mortality risk

and the metabolism of brown fat, a metabolic response termed ‘non-shivering thermogenesis’ [2]. All of these defences against heat loss are weakened in the preterm infant, who has a thin skin, increased transdermal water loss, no subcutaneous fat [3], and who has been born before having the opportunity to lay down any brown fat [2]. In premature babies, insensible water loss can amount to 3  ml/kg per hour, and even in term babies, it is around 1 ml/kg per hour. These losses can be minimized by nursing the baby in a humid environment, but this is rarely practicable. Heat loss through convection and conduction can be reduced by nursing the neonate in a warm environment. In surgically ill neonates, further heat loss occurs in vomitus, tachypnoea, and, of course, during the massive increase in surface area that occurs when the baby’s abdomen in opened by the surgeon, or where there is evisceration at birth, as occurs in babies with gastroschisis or ruptured exomphalos. Babies who become cold must try to maintain temperature by using their scarce energy stores, but these are rapidly exhausted. The well child can replenish these energy stores by feeding. The surgically ill baby cannot. Cold then leads to further depletion of energy stores, protein breakdown, acidosis, sclerema, increased oxygen consumption, sepsis, and death. It is clear from . Fig.  2.3 that keeping the baby warm minimizes the metabolic rate and oxygen consumption, but the zone of thermal neutrality is narrow. Hypothermia is formally defined as a core temperature lower than 36 °C. Prevention is much better than cure. Keeping a baby warm requires strategies different than those to warm  

Birth Weight (gm)

4000

0.1

LGA 1. 2000

5 AGA 10 30 70

SGA

90 40 Pre-term Gestation (wks)

37

Term

42

Post-term

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L. Hadley and K. Lakhoo

..      Fig. 2.3  Metabolic rates, temperature, and oxygen consumption

Metabolic Rate, Temperature and O2 consumption Normal range of neonatal temperature control

2 Metabolic rate

O2 Consumption

o

o

36 C Hypothermia

up a cold baby. A baby can be kept warm by enveloping him, and his head, in an insulating material such as a blanket or aluminium foil, obviously ensuring that the airway is not obstructed; doing this to a cold baby will simply keep him cold. The mother’s body is an excellent heat source, and the so-called kangaroo care [4] also aids in maternal bonding [5]. It would appear that, at least in the short term, fathers are capable substitutes [6]. Ideally, surgically ill babies should be kept warm in incubators when these are available. Most babies can be accommodated in incubator temperatures of 32–33 °C. Babies in incubators still lose heat by radiating it into space. In a perfect world, double-lined incubators would be standard, but radiation losses can also be reduced by covering the baby with a sheet of paper. Making a cold baby warm requires an external heat source, and warming should take place slowly [7]; attempting to rapidly warm a baby with an electrical heater inevitably results in dermal burns. During rewarming, it is wise to check the baby’s blood sugar levels. 2.4  Cardiovascular Adaptation

Before birth, the baby’s circulation is based upon the placenta, which acts as lung, kidney, and nutrient supply. Thus, the umbilical vessels are of paramount importance. Blood arriving at the foetus from the umbilical

37 C Zone of Thermal Neutrality

Hyperthermia

vein is shunted across the liver through the ductus venosus and away from the lung through the foramen ovale. The foramen ovale is simply a flap ‘gate’ that is held open because the pressure in the right atrium is higher than the left atrial pressure. Because the lungs require little blood flow before birth, blood is also shunted from the right ventricular outflow into the aorta through the ductus arteriosus before returning to the placenta through the umbilical arteries (. Fig. 2.4). When the obstetrician clamps the cord, flow to the right atrium is reduced, and the right atrial pressure falls. There is a simultaneous increase in left atrial pressure in response to increased pulmonary blood flow that follows the decreased pulmonary vascular resistance caused by lung expansion with the first breath. This allows the ‘gate’ to close the foramen ovale. With the onset of breathing, there is an increase in peripheral oxygen concentration that stimulates the ductus arteriosus to close a muscular contraction probably mediated through prostaglandin. The closure of both the foramen ovale and the ductus arteriosus is temporary. They can be reopened by anything that increases right atrial pressure relative to the pressure in the left atrium or that decreases peripheral oxygen concentration. Permanent closure is not achieved in the neonatal period. Reopening these temporarily closed shunts restores the infant to the fetal circulatory pattern, but there is no longer a placenta that can act as a lung or kidney,  

19 Neonatal Physiology and Transport

Pulmonary trunk Ductus arteriosus Aorta Pulmonary veins Superior vena cava

2.5  Respiratory Adaptation

Lung Foramen ovale

Left atrium

Right atrium Right ventricle Inferior vena cava Ductus venosus

Portal vein Umbilical vein Umbilicus

Placenta

kg per hour in a 3-kg baby will result in an error of 10% of the circulating blood volume by the end of the day. Similarly, all losses should be carefully measured and replaced.

Umbilical arteries

Descending aorta

..      Fig. 2.4  Schematic diagram of fetal circulation, with red indicating the highest level of oxygen saturation, blue the lowest, and purple an intermediate level

and unless the adult circulatory pattern can be rapidly re-established, the infant will die. Pulmonary hypertension, seen, for example, in neonates with diaphragmatic hernia, will cause an increase in pressure on the right side of the heart, a right atrial pressure that will exceed left atrial pressure, reopening of the foramen ovale, and ultimately reduction in peripheral arterial oxygen concentration and reversal of ductal closure. Without a placenta, this circulatory pattern is unsustainable. Pulmonary vascular resistance can be increased, and the fetal circulation reproduced, by hypoxia, acidosis, catecholamine secretion, hypothermia, or hypoglycaemia, as well as conditions that primarily cause pulmonary hypertension. The circulating blood volume of a term neonate is in the order of 80 ml/kg body weight [8]. This small volume means that precision is essential in the prescription of intravenous fluids, as an apparently trivial error of 1 ml/

During normal delivery, the fluid that has filled the lungs during fetal life is expelled, and the lungs are expanded with air during the first breath. Along with lung expansion, there is a reduction in pulmonary vascular resistance and a redirection of blood flow to allow gas exchange. Neonates are obligatory nasal breathers and obligatory diaphragmatic breathers. Resistance to air flow is increased by nasogastric intubation, and for this reason—as well as the danger of perforation of the cribriform plate during insertion [9]—orogastric intubation is preferred in this group of patients. Abdominal distension of any cause will impair diaphragmatic mobility and therefore impede breathing. The number of alveoli in the neonatal lung is less than 10% of the adult quota, but new alveoli are continually added up to 8 years of age. Despite this paucity of alveoli, the resting neonate requires more oxygen per kilogram body weight than an adult, so the neonate is at risk if oxygen requirements are increased or if any pathology diminishes the surface available for gas exchange. Alveolar stability is maintained by surfactant, a phospholipid wetting agent produced by the type II pneumocyte, which reduces the surface tension in the fluid lining the alveoli. Adequate levels of surfactant are achieved around 35  weeks of gestation. Babies born before this are at risk of developing hyaline membrane disease. It is possible to predict lung maturity antenatally by measuring amniotic fluid phospholipid concentrations. Air flow is proportional to the fourth power of the radius of the airway, and a small reduction in calibre (e.g. by mucosal oedema) can have a major effect on resistance to air flow and therefore on the work of breathing. Decreased ventilation will result in alveoli being perfused but not aerated, creating an intrapulmonary shunt, with a fall in peripheral oxygen saturation and an increase in the partial pressure of carbon dioxide in the arterial blood (paCO2). Aspiration of vomitus is common in surgical babies at all phases of their management and is a leading cause of airway oedema, lung contamination, and death [10]. It can be prevented simply by never allowing a surgically ill baby to be nursed supine. A neonate cannot turn over to protect his airway, and vomiting in a supine position inevitably leads to aspiration. Babies are perfectly happy on their sides or prone, and the culture of nursing babies supine has little merit [11]. The canard that reduces the

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risk of sudden infant death syndrome (SIDS) is vastly outweighed by the numbers lost each year to aspiration pneumonia. Similarly, analgesia is important for postoperative respiratory care, as a baby in pain will not breathe deeply, or cry, and will have diminished respiratory excursion, leading to atelectasis, intrapulmonary shunting, and ultimately infection [12]. After thoracic or upper abdominal surgery, adequate analgesia may obviate the need for postoperative ventilation [13]. Immaturity of the respiratory centre is held to be the cause of apnoea in prematurity. This usually responds to tactile stimulation but may require treatment with theophylline. The risk of apnoea following a general anaesthetic remains for up to a year postnatally in formerly premature babies. All such babies undergoing an anaesthetic for whatever reason should be kept under observation, with apnoea monitoring, for 24 hours after surgery. 2.6  Clinical Evaluation

Because babies cannot vary their tidal volume, their initial response to inadequate ventilation is to increase the rate of breathing. Due to the flexible cartilaginous nature of the chest wall, any increase in the work of breathing is manifest by intercostal, sternal, and subcostal recession as well as alar flaring. As the neonate tries to increase positive end-expiratory pressure (PEEP) to maintain alveolar patency, grunting may occur. The increased work of breathing will eventually tire the baby, who will be unable to sustain these compensatory tactics and will go into respiratory failure. Babies with clinical signs of respiratory insufficiency should receive supplementary oxygen pending investigation with a chest x-ray and blood gas analysis, if available. Any increased work of breathing associated with abdominal distension can often be ameliorated by the passage of an orogastric tube and maintenance of gastrointestinal decompression. Viscid tracheal secretions can sometimes be suctioned following humidification, best effected by nebulization with saline. 2.7  Nutrition

The provision of energy as well as the substrate for growth and development is critical to the neonate, and the provision of adequate nutrition is particularly important for the developing brain. Perinatal deficiencies may have lifelong consequences for the patient, particularly with regard to brain growth and development [14]. Nutrition is also pivotal to wound healing, temperature maintenance, and immune function.

Babies who start life with the handicap of intrauterine growth retardation, and those with surgical disorders that are not promptly recognized, are at particular risk of neonatal malnutrition. Whilst normal babies can be fed through the alimentary tract, the surgically ill neonate is frequently unable to tolerate feeding. In the developed world, this conundrum is resolved by using total parenteral nutrition (TPN), but in many developing countries, this is unavailable. The standard of care in the developed world has evolved on the back of the availability of TPN and is often inappropriate care when TPN is unavailable. As getting energy and substrate into the patient is a priority, there may be no alternative to adjusting surgical strategy to allow early use of the alimentary tract. This may involve placing feeding tubes distal to, or through, an anastomosis or creating a stoma above, or instead of, an anastomosis. An extracorporeal gastrointestinal bypass can be created by aspirating bile-containing fluid from above an obstruction and returning it with a feed either via a stoma or via a trans-anastomotic tube, distal to the obstruction. Even when full feeds are not tolerated, there is merit in providing ‘trophic’ or ‘trickle’ feeds that maintain the integrity of the intestinal mucosa [15]. The advent of the human immunodeficiency virus (HIV), particularly the recognition of the seroconversion of breast-fed babies, has added a further confounding variable [16]. Breast milk is the best, cheapest, and generally most readily available feed for babies, and it is ideal for the surgical patient. These advantages must be weighed against the risk of transmission of HIV and the economic circumstances of the family [17]. It should be remembered that breast milk contains lactose and that many gastrointestinal disorders result in temporary lactose intolerance with resulting diarrhoea [18]. The term neonate requires about 120 kCal/kg per day to maintain health. The surgical neonate, after a very brief postoperative increase in metabolic rate that lasts only 4–6 hours [19], may require fewer calories than normal due to immobility and growth inhibition as well as reduced thermogenesis [20]. Providing too many calories (overfeeding) may increase CO2 production from lipogenesis. The premature baby has an increased caloric requirement, up to 130 kCal/kg per day [21]. 2.7.1  Hypoglycaemia

SGA babies who have diabetic mothers or who have specific conditions such as Beckwith-Wiedemann syndrome are at risk of hypoglycaemia in the first few hours of life. Failure to recognize hypoglycaemia will result in unnecessary neurological morbidity. Clinical signs include apnoea, the tremors or jitteriness, followed by

21 Neonatal Physiology and Transport

convulsions. The blood sugar should be kept above 2.2  mmol/l by infusion of 10% dextrose if necessary. The blood sugar level should be monitored in all at-risk babies. 2.7.2  Hyperglycaemia

The stress response results in hyperglycaemia in many neonates with emergency surgical conditions and is common after surgery [22]. Premature babies appear to have a higher normal blood sugar, and moderate degrees of hyperglycaemia (blood glucose 4 seconds), and decreased urine output. In general, the hypotension seen in adult patients who have lost 15–25% of their intravascular volume does not occur in the pediatric population, and blood pressure alone is an insensitive indicator of dehydration in children due to their ability to increase their heart rate (. Table 4.2). A drop in blood pressure in the pediatric population typically signifies a greater loss of volume and is an ominous sign that the child no longer can compensate and risks imminent deterioration. The SNS discharge attempts to compensate for the loss in intravascular volume, but when the acidosis persists and overcomes the vasoconstriction, capillary leak may occur as well. When the patient presents in a delayed fashion or is poorly resuscitated, the pediatric patient may develop tachypnea in an effort to decrease the acidosis that is pro 

..      Table 4.2  Clinical effects of dehydration based upon percentage of body weight decrease Dehydration (% body weight)

Clinical observation

5%

Increase in heart rate (10–15% above baseline) Dry mucous membranes Concentration of the urine Poor tear formation

10%

Decrease in skin turgor Oliguria Soft, sunken eyes Sunken anterior fontanelle

15%

Decrease in blood pressure, tachycardia, tachypnea Poor tissue perfusion and acidosis Delayed capillary refill

Source: Modified from Zuckerberg AL, Wetzel, RC. Shock, fluid resuscitation, and coagulation disorders. In Nichols DG, Yaster M, Lappe DG, Buck JR (eds). Golden Hour: The Handbook of Advanced Pediatric Life Support. Mosby-Year Book, 1991

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duced due to the low tissue perfusion occurring during the shock phase. Lethargy and decreased responsiveness to pain occur secondary to decreased cerebral perfusion and low oxygen delivery. These findings associated with a drop in heart rate and blood pressure are ominous signs, and immediate action needs to be quickly pursued. The etiology of the shock needs to be determined. The most common causes of hypovolemic pediatric shock include trauma, burns, peritonitis, severe vomiting, diarrhea, and, in some cases, hyperthermia with decreased intake, which is common with malaria. Initial management would include the management of the airway, and every patient in shock should receive 100% oxygen by a face mask until the shock resolves. If the airway needs a more definitive measure, then endotracheal intubation needs to be performed because the combination of shock and respiratory problems has a very high mortality rate. It is always important to remember that shock is a very dynamic process and changes occur rapidly—this is especially true in the pediatric population, which requires adjustments that are ongoing in the management plan. If a patient presents and is less responsive than expected, the patient must have immediate resuscitation intervention or the patient will progress toward a tragic outcome, and any further delays in treatment will diminish your chances of a good outcome. Fluid resuscitation in the hypovolemic patient requires a large-bore intravenous cannula, and locations such as the saphenous, femoral, external jugular, and intraosseous may need to be used. The goal is to replace the intravascular volume as quickly as possible with a crystalloid solution, such as normal saline and not dextrose in water. Normal saline is readily available in most areas of Africa. At Kijabe Hospital in Kenya, we do not use Ringer’s lactate with pediatric patients due to the presence of potassium in Ringer’s lactate and its effects on a patient with potentially poor renal function. . Figure 4.1 presents an algorithm for treatment of hypovolemic shock in children. Although this algorithm may need to be adjusted for each specific clinical dilemma, the figure will provide a guide for taking the necessary steps needed to prepare the pediatric shock patient for emergency surgery. In situations where the hypovolemic shock is due to acute blood loss, the resuscitation team needs to be prepared to infuse appropriate volumes of blood in an attempt to maximize the oxygen-carrying capacity, as well as the intravascular volume. The patient’s blood pressure, heart rate, respiratory rate, urine output, and mental status need to be monitored to help determine the appropriate volume to be infused. Most who work in Africa will not have access to central venous monitoring devices; therefore, these indirect measurements of intravascular volume need to act as guides for adequacy of  

Fluid Volume Resuscitation in Hypovolemic Shock Hypovolemic Shock 10–20 mL/kg IV LR or NS Remains Unstable? Repeat up to 60 mL/kg Remains Unstable? Add Inotropic Drugs: Dopamine and/or Epinephrine Remains Unstable? Measure Central Venous Pressure Continue LR or NS until CVP greater than 10–12 mmHg ..      Fig. 4.1  Algorithm for treatment of hypovolemic shock. (Source: Modified from Litman, RS. Pediatric critical care. In Litman RS (ed). Pediatric Anesthesia: The Requisites in Anesthesiology. Mosby, Inc., 2004. p. 331)

replacement. O-negative or merely type-specific blood can be infused rapidly in the pediatric patient who needs blood urgently to survive due to the shock. If the patient fails to respond to the fluid resuscitation measures, before considering an inotropic agent such as dopamine, look for an additional cause of bleeding or decreased cardiac output, such as tension pneumothorax. 4.3.2  Septic Shock

Septic shock is associated with microorganisms in the blood and the effects of toxic products with an associated inadequate delivery of oxygen to the tissues. Early septic shock can also be classified as a distributive shock, which reflects the vasodilatory effects of bacterial toxins on arterial vascular and venous smooth muscle tone causing decreased vascular resistance and venous pooling (i.e., decreased preload). Initially, the oxygen delivery can be high, with warm and well-perfused tissues, but this can change if lactic acidosis overcomes the compensatory mechanisms of the pediatric patient due to excessive demand for oxygen. Once this happens, patients will develop a hypodynamic state associated with cold, mottled extremities and hypotension. This

39 Cardiovascular Physiology and Support

late form of shock is due in part to the negative inotropic effects of acidosis and bacterial toxins on cardiac contractility but may also reflect intravascular volume depletion. Although gram-negative and gram-positive organisms are a common cause of sepsis, tuberculosis, herpes, and malaria are forms of sepsis seen more often in the African environment. In an environment where the patients arrive late in their course of distress, septic shock can be severe and the mortality very high in the pediatric population. The factors that indicate septic shock syndrome are as follows: 55 Clinical suspicion or evidence of infection 55 Temperature instability (fever or hypothermia) 55 Hypoglycemia 55 Tachycardia/tachypnea 55 Impaired organ system function –– Peripheral hypoperfusion –– Altered level of consciousness –– Oliguria –– Hypoxemia –– Acidosis –– Pulmonary edema The cardiovascular effects that implicate septic shock include lower systemic vascular resistance, increased capillary leak, and increased venous capacitance, which will directly decrease preload and therefore cardiac output. In patients for whom direct myocardial contractility is affected, the inability to provide sufficient oxygen supply for the high demand results in rapid deterioration. The patient who presents early with “warm shock” will demonstrate a significantly different picture than the delayed presenter who is hypovolemic with “cold shock.” The management of septic shock is similar to hypovolemic shock in relation to the need for oxygen and fluids, but these patients need to have the etiology of the septic shock discovered rapidly so that the toxic effect can be diminished and eventually removed from the system. Once the diagnosis of septic shock is made, management includes early antibiotics with studies showing that treatment less than 3 hours improves outcomes, appropriate fluids, and, if nonresponsive to fluids, then inotropes such as dopamine, adrenaline, and noradrenaline to maintain a perfusion pressure. If the patient has no known bacterial source of infection, then tuberculosis and malaria need to be considered and added to the antibiotics as you monitor for any signs of clinical improvement. Disseminated intravascular coagulation (DIC), renal failure, acute respiratory failure, and even liver failure can be caused by sepsis, and therefore, accurate urine output is essential, and all patients who are severe need a bladder catheter.

4.3.3  Cardiogenic Shock

Cardiogenic shock is defined as shock due to cardiac failure, which can be due to infections, trauma, drug overdose, cardiomyopathies, and congenital heart disease. Although cardiac failure may be present in other forms of shock, this form is directly due to altered cardiac function. In the newborn period, cardiogenic shock may be caused by a hypoplastic left heart, which is difficult to manage in any environment. Cardiogenic shock may also be characterized by normal cardiac contractility in the presence of increased afterload (obstructive shock). Conditions associated with this form of shock include coarctation of the aorta, pulmonic stenosis, and valvular or subvalvular aortic stenosis. The management of cardiogenic shock depends on the etiology of the hypotension, but the use of vasopressors such as dopamine and epinephrine with the addition of 5–10 ml/kg boluses of fluids may improve hemodynamics temporarily. It is critical that indirect cardiac volume monitoring be performed during the resuscitation. Arrhythmias may occur more commonly in this form of shock, and the identification of the type of electrocardiogram (ECG) abnormality will allow for improved selection of treatment options. Cardiogenic shock carries a high mortality rate, and invasive monitoring with mechanical circulatory assistance is sometimes difficult to obtain in resource-poor settings. Without surgical correction of the correctable cardiac pediatric lesions, at times only palliative care can be provided for these patients. 4.3.4  Neurogenic Shock

Cervical spinal cord injury is associated with dysfunction of the sympathetic nervous system, resulting in such cardiovascular changes as severe bradycardia, asystole, and loss of peripheral vascular tone. Cardiovascular problems known to arise from SNS dysfunction include low resting blood pressure, orthostatic hypotension, autonomic dysreflexia, reflex bradycardia, cardiac arrest, limited cardiovascular response to exercise, and alterations in skin microcirculation. Neurogenic shock is another cause of distributive shock. Thus, patients in neurogenic shock initially have warm extremities and low diastolic pressure, which may eventually develop into a situation of acidosis and a decrease in perfusion pressure. With the sudden loss of sympathetic tone, especially if the lesion is above T6, the patient may demonstrate signs of bradycardia and other arrhythmias due to the loss of the cardioaccelerator fibers. Pulmonary edema may develop due to fluid resuscitation when the loss of sympathetic tone results

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..      Table 4.3  Common cardiovascular medications

4

Drug

Pediatric dosing

Uses

Classification

Mechanism of action

Dopamine

5–20 mcg/kg per min IV

Shock

Inotropes/ vasopressors

Alpha- and beta-1 agonist; stimulates dopaminergic receptors

Epinephrine (Adrenalin)

0.01 mg/kg IV q 3–5 min prn for arrhythmia; SC/IM q 20 min–4 h for anaphylaxis or asthma

Asystole, VF, pulseless VT, bradycardia, asthma, anaphylaxis

Inotropes/ vasopressors; anti-arrhythmics; anaphylaxis

Sympathomimetic stimulation of alpha- and beta-adrenergic receptors

Phenylephrine (Neo-­ Synephrine)

5–20 mcg/kg IV bolus, then 0.1–0.5 mcg/kg/min IV; or 0.1 mg/kg SC/ IM q 1–2 h for mild hypotension; or 5–10 mcg/kg IV × 1 for paroxysmal supraventricular tachycardia (PSVT) conversion

Shock, hypotension, PSVT conversion

Inotropes/ vasopressors

Smooth muscle alpha-agonist (vasoconstrictor)

Ephedrine

10–50 mg IV (adults) prn hypotension titrated to effect

Hypotension

Inotropes/ vasopressors; decongestants

Smooth muscle alpha-agonist (vasoconstrictor)

in peripheral vasodilatation. The management of neurogenic shock depends upon the level of injury and the involvement of the levels for ventilation. If the level is below C8, then the diaphragm is intact and providing the necessary muscles of inspiration needed to maintain oxygenation. Fluid resuscitation and monitoring for bradycardia may prompt the use of intravenous atropine and even vasopressors to maintain the appropriate blood pressure. 4.3.5  Management of Shock

All forms of shock—hypovolemic, septic, cardiogenic, and neurogenic—can have similar effects on the pediatric patient and therefore have similar management plans. The foundation of oxygen delivery to compensate for oxygen utilization allows medical care providers a target to aim toward as they seek to resolve the hypovolemia, identify the organism in sepsis, search for the cardiac resolution of the shock, or treat the acute spinal cord injury and its associated physiological implications of no sympathetic nervous system. . Table 4.3 lists some common cardiovascular medications used in shock management.  

4.4  Clinical Correlations

The following scenarios illustrate the clinical impact of alterations in cardiovascular function and provide recommendations for management.

4.4.1  Case Scenario #1 4.4.1.1  Presentation

You are planning a posterior sagittal anorectoplasty (PSARP) on an 8-month-old male with high imperforate anus and unrepaired tetralogy of Fallot (TOF). The patient had a colostomy at 1 month of age and since that time has had approximately two episodes of central cyanosis, which resolve spontaneously per day. The patient is not on any medications except for iron supplement, and the room air oxygen saturation is 90%. His preoperative hemoglobin level is 8.1. He is small for his age, at 5.1 kg, and has no known respiratory issues. 1. What is the likely etiology of his cyanotic episodes? 2. How should this patient be managed intraoperatively? 4.4.1.2  Treatment

This patient has documented tetralogy of Fallot, a cardiac anomaly characterized by right ventricular outflow obstruction associated with a ventricular septal defect (VSD), overriding aorta, and right ventricular hypertrophy. Due to the obstruction of right ventricular outflow, blood flow through the pulmonary circulation in most patients occurs through persistence of the fetal connection between pulmonary and systemic circulations, the ductus arteriosus. Therefore, in these patients, oxygenated blood returning from the lungs and unoxygenated blood returning from the peripheral tissues are mixed in the ventricles through the VSD. The percentage of cardiac output passing through the pulmonary circulation determines the severity of cyanosis.

41 Cardiovascular Physiology and Support

Patients with TOF frequently experience episodes of worsening cyanosis (“tet” spells) associated with decreased pulmonary perfusion in response to stimuli that increase pulmonary outflow obstruction or decrease systemic vascular resistance. Options for treating cyanotic episodes include IV fluid boluses, pressure on the abdominal aorta, liver compression, morphine 0.1 mg/kg IV, or intravenous sodium bicarbonate. Oxygen is seldom helpful during a “tet” spell due to decreased pulmonary perfusion. During an anesthetic, it is important to avoid a drop in systemic blood pressure, as this will worsen right-to-left shunting, which can happen with inhalation agents such as halothane. Patients may respond to an IV fluid bolus, decreasing inhalation anesthetic, and vasoconstrictor drugs such as phenylephrine (alpha agonist) to increase systemic vascular resistance. Most cyanotic patients are polycythemic, which improves oxygen delivery. Ketamine is a good choice for induction because it tends to maintain systemic blood pressure. Narcotics and low-dose halothane are good choices for this particular surgery, which must be completed without muscle relaxants to allow nerve stimulation during surgery. The goal should be to extubate the patient in the immediate postoperative period to minimize airway stimulation, which can induce a “tet” spell. 4.4.2  Case Scenario #2 4.4.2.1  Presentation

You are called to see an 8-year-old, previously healthy boy with a 2-day history of abdominal pain and vomiting. On examination, the patient is moderately distended and has diffuse abdominal tenderness with involuntary guarding. The patient seems somewhat anxious, he is tachypneic, his temperature is 39.5 °C, his heart rate is 140, and his blood pressure is 90 over 45. His extremities are cool to the touch. 1. What is the likely etiology of this patient’s altered vital signs? 2. What should you do to prepare this patient for surgery?

The first and most important step in the management of this patient is to recognize that he is in shock. Due to the cardio-depressive effects of most anesthetic agents, worsening hypotension and organ dysfunction would likely result if this patient was taken directly to the operating room without prior resuscitation. Therefore, an effort should be made to optimize his hemodynamics prior to the induction of anesthesia. Because both septic shock and hypovolemic shock respond initially to expansion of the intravascular blood volume, two large-bore IVs should be started, and the patient should receive one or more boluses of a crystalloid solution. During the period of preoperative resuscitation, vital signs should be monitored frequently, and a bladder catheter should be inserted to monitor urine output as a measure of adequacy of endorgan (renal) perfusion. In addition, because sepsis is suspected, the patient should be started on a broad-spectrum antibiotic early once the diagnosis of sepsis is made. It is likely that the ultimate treatment for the cause of this patient’s shock will require surgical intervention; therefore, resuscitation should occur as expeditiously as possible.

Key Summary Points 1. Alterations in venous return (preload), vascular resistance (afterload), heart rate, and contractility all impact cardiovascular function. 2. In the healthy patient, compensatory mechanisms allow maintenance of adequate cardiac output and organ blood flow in the face of limited changes in these variables. 3. Neonates have a limited ability to increase cardiac output by increasing contractility and stroke volume and thus are dependent upon heart rate to maintain cardiac output. 4. Shock is the result when pathologic conditions severely alter one or more factors and overwhelm compensatory responses, resulting in cellular ischemia due to inadequate cardiac output or a maldistribution of blood flow. 5. Recognition and treatment of the cause of shock are central to optimizing patient outcome.

4.4.2.2  Treatment

This patient presents with an acute abdomen of 2 days duration. Based upon the findings on clinical examination, he has diffuse peritonitis. His tachycardia, low blood pressure, anxiety, and poor peripheral perfusion are consistent with circulatory shock. He is febrile and has a wide pulse pressure, which would suggest that shock may be due to sepsis. However, patients with peritonitis lose a large amount of intravascular volume due to transudative and exudative losses into the peritoneal cavity. Therefore, this patient likely also has a component of hypovolemia contributing to his shock state.

Suggested Reading Antoni H. Functional properties of the heart. In: Gregor R, Windhorst U, editors. Comprehensive human physiology, from cellular mechanisms to integration. Berlin: Springer; 1996. p. 1801–23. Guyton AC, Hall JE. Cardiac output, venous return and their regulation. In: Guyton AC, Hall JE, editors. Textbook of medical physiology. 10th ed. Philadelphia: WB Saunders; 2000a. p. 210–22. Guyton AC, Hall JE. Heart muscle: the heart as a pump. In: Guyton AC, Hall JE, editors. Textbook of medical physiology. 10th ed. Philadelphia: WB Saunders; 2000b. p. 96–106.

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Guyton AC, Hall JE. Local control of blood flow by the tissues, and humoral regulation. In: Guyton AC, Hall JE, editors. Textbook of medical physiology. 10th ed. Philadelphia: WB Saunders; 2000c. p. 175–83. Hirschl RB, Heiss KF. Cardiopulmonary critical care and shock. In: Oldham KT, Colombani PM, Foglia RP, Skinner M, editors. Principles and practice of pediatric surgery. Philadelphia: Lippincott Williams & Wilkins; 2005. p. 139–78. Holtz J. Peripheral circulation: fundamental concepts, comparative aspects of control in specific sections and lymph flow. In: Gregor R, Windhorst U, editors. Comprehensive human physiology,

from cellular mechanisms to integration. Berlin: Springer; 1996. p. 1865–915. Nichols DG, Yaster M, Lappe DG, Buck JR, editors. Golden hour: the handbook of advanced pediatric life support. St. Louis: Mosby-Year Book; 1991. Ross J. Cardiovascular system. In: West JB, editor. Best and Taylor’s physiological basis of medical practice. 11th ed. Baltimore: Williams and Wilkins; 1985. p. 108–332. Teasell RW, Arnold JM, et al. Cardiovascular consequences of loss of supraspinal control of the sympathetic nervous system after spinal cord injury. Arch Phys Med Rehabil. 2000;81:506–16.

43

Fluids and Electrolyte Therapy in the Pediatric Surgical Patient Mark W. Newton, Chun-Sui Kwok, and Kokila Lakhoo Contents 5.1

Introduction – 44

5.2

Fluid and Electrolyte Homeostasis – 44

5.2.1 5.2.2 5.2.3

 ody Water Composition – 44 B Renal Function – 44 Fluid Requirements – 46

5.3

Clinical Assessment – 46

5.3.1

Laboratory Evaluation of Renal Function – 47

5.4

Perioperative Fluid and Electrolyte Management – 47

5.4.1 5.4.2 5.4.3 5.4.4 5.4.5 5.4.6

F luid Resuscitation – 47 Maintenance Fluid Requirements – 48 Glucose Requirements – 48 NPO Period in the Pediatric Population – 49 Intraoperative Fluids – 49 Postoperative Fluid Management – 50

5.5

Summary of Fluid and Electrolyte Balance – 51

5.5.1 5.5.2 5.5.3 5.5.4 5.5.5 5.5.6

F luid Balance – 51 Sodium Balance – 51 Potassium Balance – 51 Acid-Base Balance – 51 Glucose Balance – 52 Calcium Balance – 52

5.6

Evidence-Based Research – 52 References – 53

© Springer Nature Switzerland AG 2020 E.A. Ameh et al. (eds.), Pediatric Surgery, https://doi.org/10.1007/978-3-030-41724-6_5

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5.1  Introduction

5

Perioperative fluid and electrolyte management for infants and children can be confusing due to the numerous opinions, formulas, and clinical applications, which can result in a picture that is not practical and often misleading. The basic principles of fluid and electrolyte management are similar in the neonate and the pediatric patient if one considers the exceptions, which include renal maturity, body composition, physiological losses, delivery issues, and autonomic nervous system differences. Understanding the ability of the neonate and older pediatric patient to compensate for fluid and electrolyte alterations, due to the surgical pathology, is addressed after an overview of normal fluid and electrolyte metabolism. Perioperative fluid and electrolyte management addresses dehydration, fasting status, intraoperative fluid management, postoperative issues, and transfusion therapy. When practicing in a resource-limited medical practice setting, one needs to be able to manage extremes of fluid and electrolyte issues with less laboratory and investigative infrastructure in patients who may have delayed presentation after their surgical pathology presented itself. The physician who cares for the surgical needs of the neonate and pediatric patient population must be keenly aware of the perioperative needs regarding fluid and electrolyte metabolism requirements. This understanding will increase the goal of a successful and safe surgical course for both the pediatric patient and parents. 5.2  Fluid and Electrolyte Homeostasis 5.2.1  Body Water Composition

At birth, the neonate is suddenly separated from the source of water found in the in utero environment and now is in an environment where water loss is significant from the skin and respiratory tract, thus promoting a potential for early dehydration. During this period of transition, water intake and renal conservation of fluids are necessary to maintain a homeostatic state. Total body water comprises of intracellular water (ICW) and extracellular water (ECW), with the ECW having an intravascular and interstitial component. With advancing gestational age, the amount of total body water declines from 94% of body weight in the third trimester to approximately 78% at term. This continues to decline to around two-thirds of body weight by the age of one, being similar to the composition found in adults. In the immediate postnatal period, the extracellular fluid compartment decreases as a proportion of

the body weight as a normal physiological process. Although the newborn has an interstitial fluid reserve during times of decreased fluid intake, preterm infants are at greater risk of becoming clinically dehydrated in a very short period of time due to their larger surfaceto-weight ratio, higher total water content, limited renal ability to concentrate, and greater insensible water loss from immature thin skin. The added water loss associated with radiant warmers, which are commonly found in the treatment of the newborn and especially preterm infants, can result in a rapid and progressive level of dehydration without close observation and appropriate fluid intake adjustments [1]. 5.2.2  Renal Function

The neonatal renal function does not reach adult levels until after the age of 1–2 years due to several factors [2]. The renal blood flow (RBF) gradually increases to adult levels (20% of cardiac output (CO)) around the age of 2  years. In addition, increases in the glomerular filtration rate (GFR) reflect the effects of increasing in size, not number, of the glomeruli after the age of 1  year (. Table 5.1). Although the neonate is able to cope with routine fluid and electrolyte requirements, it is during times of dehydration, acidosis, trauma, excessive fluid, and solute load that the neonate reveals its immaturity in renal function. This immaturity in renal function is even more evident in patients who are less than 34 weeks gestational age at birth; studies demonstrate that when a newborn is between 25 and 28 weeks gestational age, it takes 8 weeks for their GFR to reach that of term infants [3]. The term and preterm neonate will not have a complete diuretic response to a water load until after 5 days of age, and the preterm will have an even slower response when compared to an adult response. Newborns have a reduced ability to concentrate urine, tend to have lower thresholds for glucose excretion, have unnecessary excretions of sodium, and have poor tolerances for fluid loads, all of which are amplified in the preterm infant. The countercurrent system of the loop of Henle relies on the osmolality in the medullary interstitium. The lower osmolality of the neonatal renal medulla restricts its urine concentration capacity to a maximum of 600 mosmol/kg compared to 1200  mosmol/kg of an adult. By 1  month of age, the full-term infant’s kidney is about 70–80% mature in comparison to that of a healthy adult patient. Additional factors that may influence the renal function include maternal oligohydramnios, maternal drug use (indomethacin), polycystic disease in the family, and some forms of urinary obstruction. Any situation whereby the infant has hypoxia, hypotension, or haemorrhage may lead to a decreased RBF and a subsequent  

45 Fluids and Electrolyte Therapy in the Pediatric Surgical Patient

..      Table 5.1  Glomerular filtration rate GFR by Postnatal Age (mean ± SD) Gestational Age

1 week

2–8 weeks

>8 weeks

Normal GFR (ml/min/1.73 m2)  

25–28 Weeks

         

No. of subjects Mean – 1

SDc

29–34 Weeks

11.0 ± 5.4a

15.5 ± 6.2a

47.4 ± 21.5a, b

10

26

9

6 15.3 ±

9 5.6a

26 13.8a, b

28.7 ±

51.4

   

No. of subjects

27

27

   

Mean – 1 SD

10

15

40.6 ± 14.8

65.8 ± 24.8b

95.7 ± 21.7b

26

20

28

 

38–42 Weeks

   

No. of subjects

1

Absolute GFR (ml/min)  

25–28 Weeks

0.64 ± 0.33a

0.88 ± 0.42a

5.90 ± 5.92a, b

 

29–34 Weeks

1.22 ± 0.45a

2.43 ± 1.27a, b

10.83

 

38–42 Weeks

5.32 ± 1.99

11.15 ±

5.21b

20.95 ± 6.40b

aSignificantly

less than corresponding value in full-term infants increase compared with previous age group cMean – 1 SD represents lower cutoff value bSignificant

drop in the normal urine output. All of these factors point towards the reminder that infants (especially preterm) must have their fluid status closely monitored so that homeostasis is maintained, or approached, in the circumstance surrounding the need for surgical intervention. The lack of urine pH monitoring and more extensive laboratory testing abilities should not determine the impact that a detailed history and basic renal function monitoring can have on the improvement of surgical outcome, which involves renal function immaturity. One of the primary homeostatic functions of the kidney is to maintain proper sodium levels in the body. Urinary sodium excretion, which is directly correlated to GFR and indirectly to gestational age, becomes an issue in situations where there is sodium load or the need to retain sodium arises. The kidney’s ability to retain sodium in preterm infants will not reach the term infant’s level until they reach the gestational age of a term infant. Term infants in nonphysiological stressful situations can maintain normal sodium levels, but preterm infants less than 32  weeks’ gestational age would be considered “salt losers”. Their ability to conserve sodium is even further altered by hyperbilirubinaemia, hypoxia, and increased intraperitoneal pressure, which may decrease RBF and thus produce a state of hyponatraemia. If the sodium level goes below 120 mmol/L,

then the patient could show signs of neurologic injury, which can be irreversible. Rapid correction of hyponatraemia can also lead to irreversible neurologic injury in the form of central pontine myelinolysis. In attempting to replace the sodium in response to gastric losses, or losses due to intestinal obstruction or diarrhoea, the physician may give the neonate an excessive load of sodium, which may override the tubular functions of the immature renal system and even produce a state of hypernatraemia. Complications, including reopening of the ductus arteriosus and cerebral bleed, can be caused by hypertonicity due to the elevated sodium load. Potassium balance in the preterm infant can be an issue in the event of acidosis leading to reduced excretion of potassium and the extracellular shift of potassium, especially in the first 24–72  hours postpartum. Indeed this often occurs in many situations where surgical intervention is needed, especially if the presentation to a healthcare facility is delayed. Usually the newborn can tolerate a potassium level of approximately 6 mmol/L, and one needs to consider the technique of taking the blood sample as a cause of a falsely elevated level due to the common occurrence of haemolysed blood cells. . Table 5.2 presents the clinical significance of newborns’ physiological presentations.  

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M. W. Newton et al.

..      Table 5.2  Clinical significance of newborns’ physiological presentations

5

Physiology

Clinical significance

Low glomerular filtration due to Low perfusion pressure High renal vascular resistance

Poor tolerance volume load Poor tolerance sodium level

Only juxtamedullary glomeruli are functional   Fewer and smaller glomeruli   Smaller glomerular pore size Diminished proximal tubular function   Low blood flow to juxtamedullary nephron tubules   Less tubular mass per nephron   Glomerular-tubular imbalance

Tendency to excrete filtered sodium Low threshold for glucose excretion

Diminished distal tubular function   Shortened loops of Henle   Low tonicity in medullary interstitium   Poor response to antidiuretic hormone

Inability to concentrate urine

5.2.3  Fluid Requirements

Fluid requirements in the newborn or older child depend upon multiple factors, but the majority are determined by the insensible water loss and the newborn’s metabolic rate. The evaporation of water from the skin and the respiratory tract has environmental factors, such as air and incubator temperature, humidity, and air flow across the child’s body, as well as infant factors, such as patient position, metabolic rate, and elevation in temperature. Water loss from the premature infant is significantly greater than from the term infant, possibly due to decreased subcutaneous fat and increased permeability through the skin [1]. The combination of increased water loss in the premature infant and the use of radiant warmers without humidity, which occurs in many settings, can result in a severely dehydrated premature infant who may need resuscitation. The insensible water loss can increase 50–200% with the use of radiant warmers in the preterm infant. This can have significant impact on the intraoperative course, as the patient may arrive in the operating theatre dehydrated even though receiving maintenance fluids in the immediate preoperative period. The low-tech approach to humidity can be achieved merely by keeping an open container of water near the newborn while under warming lights. Fluid chambers need to be cleaned and changed routinely in an effort to decrease infection in the nurs-

ery unit, and the fluid level of radiant warmers, which may vary depending upon the manufacturer, needs to be monitored. 5.3  Clinical Assessment

The physical characteristics of the newborn may give the examiner a clue as to a possible renal dysfunction. Lowset ears, flattened nose, and VATER (vertebrae, anus, trachea, esophagus, and renal) or VACTERL (vertebral and spinal cord, anorectal, cardiac, tracheo-­esophageal, renal and other urinary tract, limb) syndromes may heighten the suspicion of congenital renal abnormalities. An accurate measurement of blood pressure is sometimes difficult but equally necessary if renal dysfunction is suspected. The occurrence of an elevated systolic blood pressure, or systolic blood pressure greater than 90 mm Hg in the term infant, may indicate renal insufficiency, but these findings are also commonly associated with other issues such as pain or hunger. The absence of abdominal wall musculature can indicate prune belly syndrome, and the evidence of one umbilical artery connecting to the placenta correlates with an increased incidence of cardiac and renal malformations. The examination of the placenta is an easy task that could benefit the care of the newborn surgical or nonsurgical patient where renal function is in question. Oedema in the newborn, which is abnormal in the term child, can also indicate renal disease related to an underlying cardiac problem, hypoxia due to respiratory insufficiency, or low albumin levels. The infant with liver failure may present with signs of oedema that are unrelated to any renal problems. A history of hypoxic injury commonly leads to a marked decrease in urine output. Sepsis is the other common cause of acute renal failure in the neonate. A syndrome of inappropriate antidiuretic hormone (ADH) may accompany hypoxic injury, which may lead to fluid and electrolyte abnormalities. Once hypotension and oxygen needs are addressed, fluids may need to be restricted until diuresis occurs. The perioperative patient who arrives late in the progression of a surgical disease may present with signs of severe dehydration. It often is difficult to get a detailed history regarding urine output in the neonate, although it is usually possible to have an indication of the fluid intake within the past 24  hours and sources of abnormal losses. The clinical evaluation of the neonate, which would include alertness, skin turgor, capillary refill time, fontanelle size, heart rate, blood pressure, and presence or lack of urine, would assist in the determination of fluid status. During the hospital admission, serial measurements of weight and monitoring of fluid intake as well as fluid losses are essential. Routinely, if the urine

47 Fluids and Electrolyte Therapy in the Pediatric Surgical Patient

output history is questionable, the placement of gauze near the urethra opening could be weighed to assist in obtaining objective information needed to estimate urine output preoperatively.

..      Table 5.3  Signs and symptoms of dehydration Percent of body weight

Signs and symptoms of dehydration

1–5% (mild)

History of 12–24 hours of vomiting and diarrhoea Dry mouth Decreased urination

6–10% (moderate)

Tenting skin Sunken eyes, fontanelle Oliguria Lethargy

11–15% (severe)

Cardiovascular instability: mottling, hypotension, tachycardia Anuria Sensorium change

20%

Coma Shock

5.3.1  Laboratory Evaluation of Renal

Function

Obtaining the serum creatinine level, which is available in most hospital settings, is the simplest method of assessing the glomerular function in the neonate. Initially in the first 24 hours of life, the creatinine and even sodium level is a representation of the maternal electrolyte balance and renal function. A number of factors determine newborn creatinine levels such as maternal levels, gestational age, muscle mass, and renal function. Increasing creatinine levels over the first few days of life indicates some form of renal dysfunction. If an infant is born at a gestational age of 25–28  weeks, it will take approximately 8 weeks before the GFR and thus serum creatinine levels approach the levels of a term infant [3]. A urinalysis that shows the colour (concentration, presence of urobilinogen), red blood cells, white blood cells, protein, and glucose can help to diagnose some renal problems. The observation of protein in the urine can be normal in the first few days of life and then can be expected in cases of hypoxia, congenital cardiac problems, and dehydration. Small amounts of glycosuria can be detected secondary to a low tubular reabsorption with a glucose load, and the glucose load can even result in an osmotic diuresis and dehydration. Glucose in the urine may be an early sign of sepsis.

5.4  Perioperative Fluid and Electrolyte

Management

5.4.1  Fluid Resuscitation

The severity of fluid deficit should be estimated based upon the history and clinical findings. There are no unique lab values that can accurately determine the severity of dehydration, but certainly an experienced medical care provider becomes adept at the estimation of dehydration in the pediatric population. Oliguria, lethargy, and cardiovascular instability are all symptoms commonly seen when a pediatric patient has severe dehydration [4]. Some common surgical pediatric issues that can cause severe dehydration include bowel obstruction, acute burns, intestinal perforation, myelomeningocele (open), and trauma. . Table 5.3 presents signs and symptoms of dehydration by percentage of body weight [5].  

The compensatory mechanisms for dehydration that are seen in the adult population are less well-defined in the term infant and even less so in the preterm infant. The body’s primary mechanism for compensation is the renin-angiotensin-aldosterone system, which attempts to absorb sodium and water. Renin is released from the kidneys which then prompt the release of aldosterone and ADH, which allows for the water and sodium to be reabsorbed. The newborn is able to allocate some of the extracellular fluid to the plasma volume, but this compensation is limited and will result in the loss of skin turgor. The newborn’s cardiac output is determined by the heart rate because the intrinsic heart muscle is non-­ compliant, therefore making the compensatory adjustment in preload volume very limited. If a patient arrives in a state of severe dehydration and shock, then an infusion of 20 ml/kg over less than 10 minutes must be started, followed by immediate reassessment in fluid status and further fluid boluses if appropriate. In newborns, consider use of an initial fluid bolus of 10–20 ml/ kg as these patients have a high TBW and low GFR. In situations where hypovolaemia is due to blood loss with evidence of active bleeding, there is a move towards a restrictive approach to volume resuscitation until definitive early control of haemorrhage, as well as early use of blood products. The 2016 NICE “Major Trauma” guidelines recommend an initial 10  ml/kg bolus and early use of red blood cells and crystalloids in a 1:1 ratio [6]. Urine output and concentration (appearance) are accurate and cost-effective measurements that will allow for the monitoring of the overall fluid status. The placement of an intraosseous line is now preferred if a peripheral intravenous line cannot be placed quickly during the resuscitation time in a severely dehydrated child.

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M. W. Newton et al.

..      Table 5.4  Composition of intravenous crystalloid solutions

5

Solution

Glucose (g/l)

Na+ (mEq/l)

K+ (mEq/l)

Cl− (mEq/l)

Lactate (mEq/l)

Ca2+ (mEq/l)

pH

Osm

5% dextrose

50

–

–

–

–

–

4.5

253

Ringer’s

–

147

4

155

–

4

6.0

309

Lactated Ringer’s

–

130

4

109

28

3

6.3

273

D5 lactated Ringer’s

50

130

4

109

28

3

4.9

525

D5 0.22%

NSS∗

50

38.5

–

38.5

–

–

4.4

330

D5 0.45%

NSS∗

50

77

–

77

–

–

4.4

407

–

154

–

154

–

–

5.6

308

0.9%

NSS∗

Note: *NSS normal saline solution

Studies comparing crystalloids versus colloids in fluid resuscitation in children with sepsis or dengue shock syndrome have not shown any significant difference on mortality or haemodynamic stability. The 2015 NICE guidelines “Intravenous fluid therapy in children” recommend crystalloids (glucose-free and containing sodium in the range of 130–154  mmol/L) as the fluid type of choice for resuscitation [7]. Normal saline and Ringer’s lactate are therefore recommended as both are cost-effective and commonly available. . Table 5.4 shows the composition of common crystalloid solutions.  

5.4.2  Maintenance Fluid Requirements

Many formulas exist to determine the maintenance fluid levels for the infant or child. The formula of the “4-2-1 rule” works well for determining the maintenance fluids for weight groups that are less than 30  kg. In this formula, the first 10 kg of body weight is multiplied by 4 ml/h; the second 10 kg is multiplied by 2 ml/h; and any additional kilograms of weight are multiplied by 1 ml/h [8]. . Table 5.5 provides examples that apply to infants and older children to determine maintenance fluids. For neonates, the . Table 5.6 gives an example of the maintenance fluid rates required in the first 28  days of life. With regard to the type of maintenance fluid, isotonic crystalloids such as normal saline or Ringer’s lactate are recommended in the older child, although the neonate would require additional glucose as discussed in the next section [9].  

..      Table 5.5  Sample 4-2-1 rule for maintenance fluids for infants and older children Child’s body weight

Volume

9 kg:

4 × 9 = 36 2 × 0 = 0 1 × 0 = 0         36 ml/h

15 kg:

4 × 10 = 40 2 × 5 = 10 1 × 0 = 0         50 ml/h

26 kg

4 × 10 = 40 2 × 10 = 20 1 × 6 = 6        66 ml/h

..      Table 5.6  Maintenance fluid requirements for the neonate Age

Volume (ml/kg/day)

Birth to day 1

50–60

Day 2

70–80

Day 3

80–100

Day 4

100–120

Days 5–28

120–150

 

5.4.3  Glucose Requirements

Carbohydrate reserves are relatively low in the newborn and certainly will drop to low levels during the prolonged labour course often seen in some areas of

Africa. Thirty percent of the glucose reserves are stored as glycogen in the liver, but this cushion is less evident in the low birth weight or preterm infant. Within the first 4 hours of life, the newborn must be given some form of glucose, and with prematurity and a gestational age of less than 34 weeks, the ability to swallow is low; the

49 Fluids and Electrolyte Therapy in the Pediatric Surgical Patient

patient may need an intravenous (IV) line or a feeding tube. Adequate and frequent measurement of the glucose levels of the newborn, especially the newborn pending surgery, is cost-effective and will help manage the hypoglycaemia and hyperglycaemia episodes that may harm the infant. Children who are small for gestational age (SGA), have chronic illnesses, or had a prolonged NPO (nothing by mouth) period; premature infants; and infants of diabetic mothers are all at risk for hypoglycaemia during their hospital course. In SGA infants, hypoglycaemia usually occurs 24–72 hours after birth, when the glycogen stores are depleted and the breast milk production may not yet meet demand. In Kenya, we use dextrose 10% (80 ml) mixed with normal saline (NS; 20 ml) in a buretrol of 100 ml and then begin our maintenance fluids and monitor blood glucose levels. The 60 drops per ml buretrols allow us to give the appropriate volume of fluids, which will prevent volume overload (never place more than the volume for 4 hours of maintenance fluids in the buretrol) while adapting the amounts of dextrose and normal saline based upon basic lab values. Glucose level instability is commonly seen in those patients who are septic or have had a period of hypotension or asphyxia. These patients need close monitoring every hour in the operating theatre to adjust glucose levels; they all need glucose in their operative fluids to prevent the severe complications associated with hypoglycaemia. Intraoperative glucose administration is controversial, but, in general, 5% dextrose is adequate since the metabolic stress response to surgery will avoid the patient becoming hypoglycaemic. Neurosurgical cases need very close glucose control due to cerebral ischemia issues and hyperglycaemia. 5.4.4  NPO Period in the Pediatric

Population

There has been considerable debate about NPO status in children, and NPO guidelines have undergone adjustment. At this time, we no longer use the former prolonged times that once produced surgical patients who were relatively volume depleted upon the start of surgery. It has been shown that clear liquids given 3 hours before surgery results in a lower gastric volume and no change in gastric acidity. A clear liquid is one that has no particulate matter which means that you can see through the fluid if held up to the light without obstruction. Infants who are on formula need 6 hours, and breast-­ feeding infants need 4 hours at our institution in Kenya, but at some hospitals this would be considered a “clear” liquid, and only 3  hours are required for NPO.  These modifications have allowed for situations in which the children’s veins are more distended and, hopefully, chil-

dren and parents who are happier during the preoperative period. The type of surgery and reason for the surgical intervention will also dictate the ability to take fluids by mouth. Many neonates who need emergency surgery have never been on any fluids, and NPO is not an issue, but if the patient has a bowel obstruction, for example, then the need for a rapid sequence induction (anaesthesia) may override any NPO concerns. 5.4.5  Intraoperative Fluids

The calculation of intraoperative fluid requirements can be allocated into the following sections: maintenance fluids, preoperative fluid deficit, insensible losses, and estimated blood loss (. Table  5.7). The maintenance fluids per hour required based upon a patient’s weight was discussed earlier; typically, normal saline or Ringer’s lactate are the fluids of choice, as they most closely represent the plasma components. The preoperative deficit will be the maintenance fluid requirement per hour multiplied by the number of hours without any fluids. The insensible losses depend upon many factors, but primarily this will be based upon the size of the incision and whether exposure of the bowel or viscus is involved, as this will increase fluid loss (see . Table 5.7). The estimated blood loss needs to be replaced as well, with a ratio of 3 ml of normal saline for every 1 ml of blood loss. The estimated blood loss is extremely difficult to determine in the newborn surgical patient, and the anaesthesia care provider needs to calculate the esti 

 

..      Table 5.7  Intraoperative fluid requirements 1. Estimated fluid requirement (EFR) per hour (maintenance fluids)

0–10 kg = 4 ml/kg/h + 10–20 kg = 2 ml/kg/h + >20 kg = 1 ml/kg/h (e.g., 23 kg child = 40 ml + 20 ml + 3 ml, so EFR = 63 ml/h)

2. Estimated preoperative fluid deficit (EFD)

EFD = Number of hours NPO × EFR (e.g., 23-kg child NPO for 6 hours EFD = 6 × 63 = 378 ml)

3. Insensible losses (IL) (add EFR and EFD)

Minimal incision = 3–5 ml/kg/h Moderate incision with viscus exposure = 5–10 ml/kg/h Large incision with bowel exposure = 8–20 ml/kg/h

4. Estimated blood loss

Replace maximum allowable blood loss (ABL) with crystalloid 3:1

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mated blood volume and allowable blood loss for every patient before surgery. The surgery team must closely monitor blood loss and with sponge observation determine the blood loss at many points during the surgical procedure. Invasive monitoring is rare in most areas of Africa, so the use of non-invasive blood pressure, urine output, elevations in heart rate, and capillary perfusion is needed to provide clues to the overall fluid status. If a pulse oximeter is available, then the waveform changes can help with the perfusion pulse pressure, which may indicate a change in blood volume, cardiac output, or temperature. If the blood loss is above the allowable blood loss based upon the starting haemoglobin, then fresh whole blood is the most commonly transfused component in Africa. The development of a “walking blood bank” should be an aspect of each hospital involved in operative procedures. This would entail a group of donors known by the hospital lab who can donate blood for emergencies; the use of warm, fresh (non-stored) blood in the pediatric surgical patient can be life-saving. The inability to adequately warm stored blood is always an issue when a neonate requires blood transfusion. If stored (cold) blood is used, a warm bath of water with the tubing within the bath is often useful to help warm the fluids. Hypothermia can result in slow awakening, acidosis, clotting dysfunction, and, even, cardiac arrhythmias. The use of the buretrol and a three-way stopcock is the most useful manner to give blood in a newborn or very small pediatric patient. A 10- or 20-ml syringe is applied to the stopcock, and the exact amount of blood or volume of other fluid can be given and this amount accurately recorded. Blood products should be initially given in 10 ml/kg increments and as needed based upon heart rate and blood pressure; more should be added to maintain a normal intravascular blood volume. The estimated blood volume in the pediatric patient is as follows: Premature infant

90–100 ml/kg

Full-term infant

80–90 ml/kg

3 months–1 year

75–80 ml/kg

>1 year

70–75 ml/kg

Complications that can occur in the surgical neonate or pediatric patient in regard to fluids and electrolytes intraoperatively include fluid overload and pulmonary oedema, hypocalcaemia with large amounts of blood transfusions, elevated potassium levels, hypothermia due to the infusion of cold fluids, hypotension secondary to hypovolaemia, and low sodium levels if dextrose is infused without the addition of any other electrolytes.

It should be noted that, at any sign of bradycardia in the surgical neonate, one must first verify the condition of the respiratory system because bradycardia is one of the first signs of poor oxygenation. Principles for therapy for fluid overload in the pediatric patient include fluid restriction, salt restriction, diuresis or even dialysis, and albumin that is salt-poor to help with the fluid status [4]. 5.4.6  Postoperative Fluid Management

In the neonate, postoperative hypothermia is frequently an issue that will affect the recovery time as well as the ability to use fluids that are not warm because this may further decrease the body temperature. A clinical note: The cold betadine that is used for surgical procedures can prompt hypothermia because the patient can be soaking in the fluid left over from the initial prep during the length of the procedure. If it is not removed from the skin of a newborn after the surgery, the patient can develop a chemical burn that can add to the patient’s perioperative morbidity. Electrolytes, glucose, and haemoglobin levels should be determined within the first few hours after surgery, as well as the documentation of good urine output. The normal urine output of >1 ml/kg/h should be measured to help guide the fluid status; at times, a small feeding tube placed in the bladder may be the only method available to measure urine output accurately. The immaturity of the renal system needs to be considered when perioperative fluid shifts occur, as a diuresis, normally expected in older patients, may not occur in the neonate. The use of radiant warmers will help with the hypothermia but also add to insensible fluid losses; therefore, removal of these warmers will need to be considered once the temperature returns to a more normal level. Gastrointestinal losses should be replaced in addition to the maintenance fluids, on an ml-for-ml basis with normal saline containing potassium chloride (e.g. 10  mmol of KCl in 500  ml of sodium chloride 0.9%). Nausea and vomiting can be seen in the pediatric postoperative patient, but usually this is not an issue in a newborn. Third spacing from the surgical procedure occurs when fluid accumulates in a transcellular space such as the peritoneal cavity and may lead to a patient becoming intravascularly depleted despite being given routine intravenous fluids. The opportunity for the newborn to resume breast milk intake will be dictated by the surgical procedure and the surgeon’s preference. Successful surgery in the newborn period is one in which the patient is reunited with the parents so that normal bonding can resume and the patient can quickly return to the family home or village. On a clinical note, the use of gentamicin in the perioperative surgical newborn can potentially increase the

51 Fluids and Electrolyte Therapy in the Pediatric Surgical Patient

amount of renal dysfunction in this patient population, if the levels of gentamicin are not measured due to resource constraints. In a study in India, dosing of gentamicin with the following weights was considered safe [10]: 55 10 mg every 48 hours for the neonate weighing less than 2000 grams 55 10 mg every 24 hours in the neonate weighing 2000– 2249 grams 55 13.5  mg every 24  hours for the neonate weighing more than 2500 grams Gentamicin interval errors are the most common drug error reported in a recent neonatal intensive care unit (NICU) study from the United States, and certainly the effect on renal function is amplified in a setting where drug levels cannot be measured [11]. Gentamicin and ampicillin are the two most commonly prescribed antibiotics in the NICU environment, and inappropriate dosing can cause clinically significant renal damage. 5.5  Summary of Fluid and Electrolyte

Balance

5.5.1  Fluid Balance

55 Normal maintenance fluid: Ringer’s lactate at rates shown in . Table 5.5. 55 Resuscitation fluid: 20  ml/kg bolus using sodium chloride. 55 Preoperative dehydration caused by: vomiting, bowel obstruction, overheating, acute burns, intestinal perforation, myelomeningocele (open), open wounds, abdominal wall defects, and trauma. 55 Overhydration: may be iatrogenic. 55 Clinical assessment of fluid status: see . Table 5.3.  

 

5.5.2  Sodium Balance

55 Normal sodium requirement: 2–4 mmol/kg per day 55 Normal serum sodium: 135–140 mmol/L 55 Causes of hyponatraemia: iatrogenic with hypotonic solutions, laboratory error, polyuric renal failure, diuretic treatment, congestive cardiac failure, Addison’s disease, and maternal hyponatraemia 55 Signs of hyponatraemia: failure to thrive, seizures, and cerebral oedema 55 Causes of hypernatraemia: iatrogenic infusion, laboratory error, dehydration, and maternal hypernatraemia 55 Signs of hypernatraemia: dehydration and seizures 55 Treatment of sodium imbalance: by appropriate usage and adjustment of fluid therapy

5.5.3  Potassium Balance

55 An intracellular ion with a normal requirement of 1–3 mmol/kg per day 55 Normal serum potassium: 3.5–5.5 mml/l 5.5.3.1  Hyperkalaemia

55 Causes: bruising, haemolysis, renal failure, hypoglycaemia, tissue hypoxia and poor peripheral perfusion, haemolysed blood sample, and inappropriate potassium supplementation 55 Exacerbating factors: hypocalcaemia, hyponatraemia, and acidosis 55 Treatment required for serum potassium levels >7.0 mmol/l: –– 7.0–8.0  mmol/l without ECG changes: remove potassium source and give calcium resonium 0.5–1 g/kg in divided doses per rectum or orally. –– >8.0  mmol/l and/or ECG changes (depressed P waves, peaked T waves, wide QRS complexes): emergency treatment required. –– Emergency treatment for hyperkalaemia: 1. Remove source of potassium. 2. 10% calcium gluconate: 1.0  ml/kg lV (dilute 50:50, give over at least 2 minutes). This has a transient effect on electrocardiogram (ECG), not on K+ concentration. 3. Salbutamol: 4 μg/kg over 10 minutes. 4. NaHCO3: can be tried, especially if acidotic. Dose is 2 mmol/kg (= 4 ml/kg 4.2% NaHCO3) at 1–2 mmol per minute. 5. Glucose: 0.5  g/kg per dose: 5  ml/kg of 10% dextrose or 2 ml/kg of 25% dextrose or 1 ml/kg of 50% dextrose, over 15–30 minutes. 6. Insulin: 0.2 unit per gram of glucose, 1.0 unit/ kg insulin with 4  ml/kg 25% dextrose over 30 minutes. 5.5.3.2  Hypokalaemia

55 Serum potassium: 10 kg per 24 hours

21–40

1500 mL

Adolescent (11–17 years)

0.8–1.5

20 mL/kg for each kg >20 kg per 24 hours

>40 kg

1500 mL/m2 per 24 hours

Adapted from Mirtallo, et  al. Safe Practices for Parenteral Nutrition. JPEN 2004 aAssumes normal age related organ function

Additions

Source: Adapted from Kerner JA. Manual of Pediatric Nutrition. John Wiley & Sons, 1983

..      Table 6.3  Trace mineral requirements Trace mineral

Recommended intake mcg/kg/daya,b

Copper

20

Selenium

2 mcg/kg/day

Chromium

0.14–0.2 mcg/kg/dayc

Manganese

1 mcg/kg/dayd

6.2.4  Fluid Needs

Fluid and electrolyte needs vary with the patient’s age as well as underlying condition and losses; this requires monitoring for adequacy of supplementation. Routine fluid requirements in children are given in . Table 6.5.  

aIncrease

in patients with high intestinal losses bDecrease in patients with obstructive jaundice cOmit in patients with renal dysfunction dOmit in patients with obstructive jaundice

6.3  Pathophysiology of Malnutrition 6.3.1  Requirements for Nutrition Support

..      Table 6.4  Zinc requirements Age

Recommended intakea

Preterm infants

400 mcg/kg/day

Term infants

3 months: 100 mcg/kg/day 6 months: 75 mcg/kg/day

Children

50 mcg/kg/day

Source: Adapted from Greene HL. Am J Clin Nutr 1988 aIncrease supplementation in patients with high stomal losses or diarrhea

Many studies indicate that African children invariably suffer from micronutrient deficiencies due to poor maternal nutrition. In particular, Vitamin A has been singled out [11].

Pediatric surgical patients who require nutritional support include those who normally would fall within the 50th percentile on their weight charts but who, for one reason or another, have not been able to feed orally for more than 5  days or those whose surgical problem place them at high risk of malnutrition. Such children include those who have a poor absorptive capacity, those who have high nutrient losses, such as would occur with small bowel enterostomies and fistulas, and those with surgical conditions that result in an increase in nutritional needs secondary to increased catabolism. Increased catabolism will be seen in burns and conditions of prolonged sepsis (e.g., peritonitis due to bowel perforation in complicated enteric fever) [12]. Food in the intestinal tract has both direct and indirect beneficial effects, as indicated in . Fig. 6.1. Enteral feeding has a positive effect on anatomy and function of the gastrointestinal tract and has systemic effects that improve immunologic defences [13].  

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..      Fig. 6.1  Normal intestinal function. (Courtesy of European Society for Clinical Nutrition and Metabolism (ESPEN), Guidelines on Enteral Nutrition)

Food in the gastrointestinal tract

Direct effects

Increased desquamation

Indirect effects

Increased local nutrition Motility secretion

Hormone release

6

Paracrine effects

Endocrine effects

Growth

6.3.2  Chronic and Acute Illnesses

Necessitating Specialised Nutritional Support

Prolonged chronic illnesses that result in overall reduction in total caloric intake will result in poor nutritional state. In addition, any condition in which there is injury to the intestinal mucosa or reduction in total absorptive surface area of the bowel, either from local or systemic disease or any condition in which there is a reduction in overall length of bowel, may result in quantitative nutritional deficiencies and a need for nutritional support. These conditions include, but are not limited to, the following: 55 The neonate with an ileostomy 55 Antenatal rupture of exomphalos or gastroschisis 55 Extensive intestinal resection with short gut and decreased transit time 55 Necrotising enterocolitis 55 Intestinal atresia 55 Midgut volvulus where there is extensive mucosal damage 55 Massive injury, especially to the gastrointestinal tract, in conflict and various situations of violence, where enteral feeding is not feasible 55 Inflammatory bowel disease 55 Pediatric burns 55 Complicated bowel resections from perforations in enteric fever 55 Oesophageal strictures from ingestion of corrosives 55 Achalasia of the cardia

Nerve stimulation

6.4  Nutritional Evaluation 6.4.1  Cultural and Nutritional History

Generally, most communities in Africa place more value on boys than girls. After birth and until babies are weaned, there is usually no difference in nutritional status between girls and boys if the mother is generally well nourished herself. On weaning, however, gender differences in nutritional status in most communities in Africa are more likely to develop, with the boys being favoured. The number of children in the family also may also have a considerable impact on their nutritional status. A history of nutritional intake will be essential. A detail of the composition of the diet for a typical day will give a good indication of the type of nutritional deficiency that may exist. A history of the source of water may help to identify potential micronutrient deficiencies. If these are found to be present, they should then be added to the diet. Teenage and unmarried mothers are more likely to have undernourished or malnourished children because they generally belong to the lower socioeconomic classes and thus may not be able to obtain adequate food. These factors as well as the specific disease conditions listed in the previous section may be indications for additional nutritional support. 6.4.2  Physical Examination of the Child

Physical examination of the child will help to determine the degree of nutritional deprivation. The traditional parameters to measure include the weight and

59 Nutrition Support

height, which can be compared with standard age, weight, and height charts and the triceps skinfold thickness or mid-­arm circumference determination. Among the various indices that help in determining nutritional status in children are anthropometric indicators, specifically weight-for-age, height-for-age, weight-forheight, weight/height index, upper arm anthropometry, and head circumference [14]. For preterm infants, crown-­heel length and weight gain are the most sensitive indices of the adequacy of intake of nutrients [8, 14, 15]. In situations in which growth measurements are outside of the normal range (e.g. 97th%), percentiles are no longer helpful for quantifying the degree of malnutrition. Most children would have a form of ‘road to health’ charts which would have recorded their health progress within their first 5 years. Subsequently, the World Health Organization recommends using standard deviation scores or z scores to better define nutritional status and growth in children as they represent the number of standard deviations above or below the median value [16]. 6.4.3  Laboratory Investigations

Basic investigations required to confirm the proposed clinical diagnosis will be covered in the relevant chapters of this book. The discussion in this chapter is confined to the diagnosis and management of nutritional deficiency. The most helpful diagnostic indices of nutritional status are the physical examination findings noted in the preceding section. Laboratory investigations should include serum albumin and protein determination, although there are some limitations to their utility. They may be normal even with significant malnutrition, and, conversely, they can be low in circumstances of excess losses or decreased synthesis. Before parenteral nutrition is given, it is important to check baseline levels of liver function tests, as well as levels of serum urea, electrolytes, and minerals (specifically, calcium, phosphorus, and magnesium). If parenteral nutrition support is deemed necessary, following placement of the central venous catheter, a chest X-ray will be needed to confirm the adequate placement of the catheter tip.

6.5  Management of Undernutrition

and Malnutrition

6.5.1  Oral Feeding

Indirect methods of improving the caloric content of the food being given orally include cup and spoon feeding. Oral supplements may also need to be given.

Antiemetics may be given for nausea and vomiting, or agents to help improve gastric emptying can be tried. If all these fail to improve the patient’s tolerance of oral intake and nutritional status, the next step will be to give enteral feeding. Normally available local foodstuffs can be used if their caloric value can be determined. These can be blended and fed to the patient as needed. Dietetic advice and support is crucial for the mother to also help deal with negative food myths.

6.5.2  Enteral Feeding

If the gastrointestinal tract is at all functional, then the enteral route should be utilized for even partial nutrient delivery [17]. Tube feedings can be delivered either as bolus or by slow infusion, depending on the patient’s nutritional requirements, the composition of the feed being given in terms of solute load, the capacity of the child’s stomach to accommodate the quantities being fed, and the length/absorptive capacity of the bowel. Various available commercial preparations can be used. In resource-poor settings, a dietitian should be engaged who would be able to use locally available foodstuffs to prepare high-energy blends to which additional nutrients can be added based on any identified deficiencies. It is important when enteral feedings are being given to ensure that the required amount of energy is being ­delivered [8, 15, 18].

6.5.3  Parenteral Feeding

Parenteral feeding can be given as an adjunct to other nutrition or as total parenteral nutrition if the period of starvation is prolonged or if enteral feeding is going to be impossible. Premature and term infants have limited nutritional reserves and are able to tolerate starvation or semi starvation for only 1–3 days; when it is clear that the infant will not tolerate enteral nutrition, then parenteral feeding should be initiated within the first 2 days of life wherever possible. In circumstances where parenteral nutrition is not available, other means of providing a protein substrate and glucose for energy with some fat for absorption of fat-soluble vitamins must be utilized. This may include giving daily aliquots of fresh frozen plasma with 10% glucose and intralipid solution. An alternative would be to provide enteral nutrition using a trans anastomotic tube. As noted, older children with an adequate nutritional history can tolerate 4–5 days without nutrition support [19]. For those who present with malnutrition, parenteral support should be initiated sooner. Administration can be by a peripheral line for those requiring immediate support but whose

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conditions are expected to improve within 1–2  weeks [20]. Lower dextrose concentrations of no more than 12.5% dextrose should be given through a peripheral vein, and the total osmolarity must be kept under 900– 1000  mOsm/L.  A peripheral vein can be used only for short-term infusion and must be checked on a frequent basis and discontinued immediately if there are any signs of thrombophlebitis. A catheter can also be placed through a peripheral vein and then advanced until it is in a central position. The pressure from these catheters correlates well with centrally inserted catheters [21]. Administration can also be through a centrally placed venous line. It is important to ensure that the tip of the central catheter is adequately placed before the solutions are infused. With centrally placed catheters, it is possible to give higher concentrations of dextrose and thus deliver more calories. In all cases, nutritional support must include lipid, an energy source (usually dextrose), and amino acids. As noted previously, in environments where not all of these preparations are available, anecdotal experiences suggest some benefit in the use of alternative sources, including aliquots of fresh frozen plasma for small babies or intravenous preparations of amino acids, which can be administered with dextrose preparations. These alternative options should not be used for prolonged periods but only in the short term. 6.6  Monitoring Nutritional Outcomes/

Tolerance

Nutritional outcomes are monitored, including a daily assessment of the overall clinical status of the patient, the state of hydration, and weight change. Initially, if possible, daily monitoring of electrolytes, magnesium, phosphorous, calcium, glucose, creatinine, and urea levels should be performed. Once the patient has stabilised, these parameters can be assessed much less frequently.

of the solution given by introducing water into the mixture or slowing the rate of delivery will resolve the problem over a period of time. Rarely will the feeding have to be discontinued. Pulmonary aspiration may occur if amounts fed are not controlled [15]. This is particularly true if the patient has swallowing problems and therefore cannot protect the airway. If there is any question about satisfactory placement of the tip of the enteral tube, a simple plain radiograph of the abdomen will be able to confirm the placement of the catheter if it is radio-opaque. If the tube is not radio-­ opaque, a small amount (5  mL) of contrast can be placed in the catheter prior to the x-ray. 6.7.2  Complications of Parenteral Feeding

Complications of parenteral feeding are numerous and can include bacteraemia and septicaemia, air embolus, pneumothorax, hypo- or hyperglycaemia, thrombosis, hyperosmolality, metabolic acidosis, and hyperammonaemia. Other complications include cholestasis, migration of the catheter, and catheter blockage. Each complication has to be managed on its own merits. The metabolic complications, such as hypo- or hyperglycaemia and metabolic acidosis, can be managed by adjusting the parenteral nutrition solution. The most serious complication is catheter-related sepsis. Therapy for suspected sepsis involves early administration of broad spectrum antibiotics which can then be adjusted based on the organisms identified by blood culture. If the patient continues to have fevers or is clinically deteriorating, the parenteral catheter will need to be removed, and the sepsis controlled before consideration is given to placing a new catheter. Significant efforts for prevention of catheter-related blood stream infection such as hand hygiene, antiseptic skin care, and the use of tunnelled catheters or subcutaneous ports should be made in all patients requiring a central catheter. In addition, early and definitive treatment in effort to clear infection will serve to decrease morbidity and mortality [22].

6.7  Postoperative Complications 6.7.1  Complications of Enteral Feeding

6.8  Prevention of Poor Nutrition

Complications with enteral feeding are less common than with parenteral nutrition. Such complications are summarised here. If the feeding contains an excess of electrolytes, these can be absorbed into the circulation, resulting in electrolyte imbalance. The concentration of the feeding or the rate of feeding may not be tolerated, with resultant nausea, abdominal cramps, vomiting, diarrhoea, or—less often—constipation. These are usually managed symptomatically, and often just a dilution

Poor nutrition in the surgical patient affects the clinical course of the disease and the clinical outcome of the patient. Nutrition starts in utero. Attention must be given to appropriate educational programmes to ensure that pregnant women are well nourished and eating suitably balanced diets. This can involve addressing nutritional taboos, such as the belief that if the mother eats eggs in pregnancy, the delivery will be difficult.

61 Nutrition Support

Nutrition for children must ensure adequate intake of calories, minerals, and vitamins that will maximise their growth. Specific known dietary deficiencies peculiar to some areas (e.g., iodine deficiency, which causes specific surgical problems) need to be addressed. Preoperative assessment of surgical patients must include their nutritional status. Any deficiencies identified must be corrected wherever possible before surgical intervention is undertaken. Where this is not possible, postoperative management must include special attention to nutritional correction. 6.9  Ethical Issues

Traditionally and culturally, food and water are considered basic to the needs of each individual person. The modern practice of delivering nutrition and fluids via enteral and parenteral routes now challenges these values, adding on religious and moral dimensions as well as playing out issues of human rights. This is particularly the case when children have complex congenital abnormalities with poor prognosis. Decisions on starting or stopping feeding by oral, enteral, or parenteral means in most countries in Africa require physicians to adhere to strict institutional policies, which should be developed for this purpose, as the increasing possibility of legal challenges cannot be ruled out [23]. More complex discussion of specific issues is beyond the scope of this book. Additionally, resource constraints in the region would affect the range of options available to the surgeon and the available modes of administration in terms of equipment availability. 6.10  Evidence-Based Research

. Tables 6.6 and 6.7 present, respectively, a guideline for nasojejunal tube placement and a review of various feeding issues in preterm babies.  

Key Summary Points 1. Preoperatively, a majority of Pediatric patients in most countries in Africa are frankly malnourished or borderline malnourished, which has implications for postoperative outcomes, including various degrees of poor wound healing. 2. Initial assessment of nutritional status is a crucial step in determining the surgical plan for the child. 3. If surgery is elective, it is better to improve on nutritional status preoperatively. This is the best opportunity to maximise postoperative outcomes.

4. If surgery is emergent, supplemental nutrition should be offered as soon as possible. 5. Patients undergoing surgery who will suffer long periods of ileus postoperatively require careful planning for nutritional support. 6. Patients with high metabolic requirements postoperatively also require nutritional support. 7. Enteral feeding is always preferred, offering fewer complications and providing important benefits. 8. Necessary baseline tests include serum electrolyte estimation, serum protein levels, and liver function. 9. Attention to nutrition has to start in utero, with education dispelling any nutritional myths for pregnant women. 10. Nutrition in children must ensure adequate intake of calories, as well as the required intake of minerals and vitamins to maximise their growth. As much as possible locally available foodstuffs should be used for this in order to reduce healthcare costs. 11. Institutional policies must be developed to address ethical issues in order to protect physicians.

..      Table 6.6  Evidence-based research Title

Naso-jejunal tube placement in Pediatric intensive care

Authors

McDermott A, Tomkins N, Lazonby G

Institution

The General Infirmary at Leeds, UK

Reference

Paediatr Nurs 2007; 19(2):26–28

Problem

In critically ill children, intragastric feeding is often poorly tolerated.

Intervention

A guideline for bedside nasojejunal tube (NJT) placement has been developed by a multidisciplinary group.

Comparison/Control (quality of evidence)

Audit of the practice was carried out after the implementation of the guidelines. Fifty-eight percent of the children would have definitely or probably started on parenteral nutrition.

Outcome/Effect

Reduction in requests for NJT placement under x-ray screening and reduction in the use of medication for the placement.

Historical significance/comments

Improved tolerance of enteral feeding for better nutritional outcomes in intensive care units.

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..      Table 6.7  Evidence-based research

6

Title

Feeding issues in preterm infants

Authors

Cooke RJ, Embleton ND

Institution

Ward 35, Leazes Wing, Royal Victoria Infirmary, Newcastle upon Tyne, United Kingdom

Reference

Arch Dis Child Fetal Neonatal Ed 2000; 83:F215–F218

Problem

Ensuring that the nutritional intake of sick preterm infants meets requirements for sustained growth.

Intervention

Review of various practices to ascertain whether there are any differences in outcomes among the different practices.

Comparison/ Control (quality of evidence)

The relation between measurements of knee-heel and crown-heel length is not consistent, as shown in some studies. These were thought to be the most sensitive indices of the adequacy of nutrient intake. There is no benefit in feeding formula with a protein/energy ration of 2.8 g per 100 kcal until term. Same results are obtained with a similar P/E ration if the infants are fed until between 3 to 9 corrected months.

Outcome/Effect

Feeding practices in preterm infants vary quite widely among special care baby units. Practices must be audited as a basis for their continuance.

Historical significance/comments

Different studies over a period of time have arrived at different conclusions.

References 1. Eozenou PH, Shekar M. Stunting reduction in Sub-­Saharan Africa (English). Washington, D.C.: World Bank Group; 2017. http:// documents.­worldbank.­o rg/curated/en/126621505397202676/ Stunting-reduction-in-Sub-Saharan-­Africa. 2. Kurkchubasche AG. Surgery. In: Corkins MR, Balint J, Bobo E, Plogsted S, Yarworski JA, editors. The ASPEN pediatric nutrition support core curriculum. 2nd ed. Silver Spring: ASPEN Publishers; 2015. p. 507–27. 3. American Gastroenterological Association. Medical position statement: guidelines for the use of enteral nutrition. Gastroenterology. 1995;108(4):1280–1.

4. Campbell SE, Avenell A, Walker AE. Assessment of nutritional status in hospital in-patients. QJM. 2002;95(2):83–7. 5. Johnson LR.  Regulation of intestinal growth. In: Green M, Greene HL, editors. The role of the intestinal tract in nutrient delivery. Orlando: Academic Press; 1984. p. 1–15. 6. Kerner JA. Manual of pediatric nutrition. New York/Chichester: Wiley; 1983. 7. Mirtallo J, et  al. Safe practices for parenteral nutrition. J Parenter Enter Nutr. 2004;28(6):S39–70. 8. Skipper A. Dietitian’s handbook of enteral and parenteral nutrition. 2nd ed. Gaithersburg: Aspen Publishers; 1998. 9. Greene HL, et al. Guidelines for the use of vitamins, trace elements, calcium, magnesium, and phosphorous in infants and children receiving total parenteral nutrition: report of the Subcommittee on Pediatric Parenteral Nutrient Requirements from the Committee on Clinical Practice Issues of the American Society for Clinical Nutrition. Am J Clin Nutr. 1988;48:1324–42. 10. Weiglein FC. Review of trace mineral requirements for preterm infants: what are the current recommendations for clinical practice? Nutr Clin Pract. 2015;30(1):4–58. 11. Lartey A.  Maternal and child nutrition in Sub-Saharan Africa –challenges and interventions. Proc Nutr Soc. 2008;67:105–8. 12. Marian M. Pediatric nutrition. Nutr Clin Pract. 1993;8:199–209. 13. Kudsk KA.  Importance of enteral feeding in maintaining gut integrity. Tech Gastrointest Endosc. 2001;3(1):2–8. 14. Jelliffe DB, Jelliffe EFP, editors. Anthropometry: major measurements. In: Community nutritional assessment. 1st ed. Oxford: Oxford University Press; 1989. p. 68–104. 15. Foster BJ, Leonard MB. Measuring nutritional status in children with chronic kidney disease. Am J Clin Nutr. 2004;80(4):801–14. 16. Sentongo T. Assessment of nutrition status by age and determining nutrient needs. In: Corkins MR, Balint J, Bobo E, Plogsted S, Yarworski JA, editors. The ASPEN pediatric nutrition support core curriculum. 2nd ed. Silver Spring: ASPEN Publishers; 2015. p. 531–49. 17. Jeejeebhoy KN.  Parenteral nutrition in the intensive care unit. Nutr Rev. 2012;70:623. 18. de Oliveira Iglesias SB, Leite HP, Santana e Meneses JF, de Carvalho WB. Enteral nutrition in critically ill children: are prescription and delivery according to their energy requirements? Nutr Clin Pract. 2007;22(2):233–9. 19. Braunschweig CL, Levy P, Sheean PM, Wang X. Enteral compared with parenteral nutrition: a meta-analysis. Am J Clin Nutr. 2001;74:534. 20. McWhirter JP, Hill K, Richards J, et  al. The use, efficacy and monitoring of artificial nutritional support in a teaching hospital. Scott Med J. 1995;40(6):179–83. 21. Alansari M, Hijazi M. Central venous pressure from peripherally inserted central catheters correlates well with that of centrally inserted catheters. American College of Chest Physicians. (Poster presentation). 2004. 22. Chesshyre E, Goff Z, Bowen A, Carapetis J.  The prevention, diagnosis and management of central venous line infections in children. J Infect. 2015;71:S59–75. 23. Paris JJ. Withholding or withdrawing nutrition and fluids: what are the real issues. Interview by Judy Cassidy. Health Prog. 1985;66(10):22–5.

63

Haemoglobinopathies G. Olufemi Ogunrinde and Richard Onalo Contents

7.1

Demographics – 64

7.2

Aetiology/Pathophysiology – 64

7.3

Surgical Manifestations of Sickle Cell Disease – 65

7.3.1 7.3.2 7.3.3 7.3.4 7.3.5 7.3.6 7.3.7 7.3.8 7.3.9

 cute Abdominal Pain – 65 A Acute Splenic Sequestration Crisis – 65 Gallstone Disease – 65 Orthopaedic Manifestations – 66 Genitourinary Manifestations – 68 Skin – 69 Surgical Manifestations of the Thalassaemias – 69 Postoperative Complications – 69 Prevention – 70

7.4

Evidence-Based Research – 71 References – 71

© Springer Nature Switzerland AG 2020 E.A. Ameh et al. (eds.), Pediatric Surgery, https://doi.org/10.1007/978-3-030-41724-6_7

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7.1  Demographics

7

The haemoglobinopathies are the most common genetic disorders worldwide. One in 20 people are carriers of a defective haemoglobin gene, and 300,000 babies are born each year with a major haemoglobin disorder [1, 2]. Africa is disproportionately affected, shouldering two-thirds of the disease burden [2], with the sickle cell disease particularly prevalent. The incidence of sickle cell anaemia (SCA or HbSS) is projected to rise to 400,000 by 2050 [3]. With reducing mortality, due to some effective interventions, the healthcare cost of SCA is also projected to rise astronomically. The distribution of SCD across the African continent is influenced by the resistance to severe malaria conferred by carrying a single copy of the abnormal gene [4]. Even though malaria resistance does not extend to those affected by homozygous SCD, the survival advantage of carriers means that the sickle cell trait is selected for in areas where malaria is endemic [5]. As a result, SCD is more prevalent in sub-Saharan Africa, particularly those areas bordering the equator. Sickle cell disease is an especially significant problem in Nigeria, where 24% of the population are carriers, and the condition affects two in every 100 live births. This means that in Nigeria alone, about 150,000 children are born with SCD each year [2]. 7.2  Aetiology/Pathophysiology

Haemoglobinopathies are disorders that affect the globin part of the tetramer haemoglobin molecule. Genetic defects produce basically two types of haemoglobinopathies: quantitative haemoglobinopathies like the thalassaemias where there is reduced or absent synthesis of a chain of the haemoglobin molecule and the qualitative or structural haemoglobinopathies like SCD, where there is an aberration in the structure or anatomy of an amino acid chain. Sickle cell disease is caused by an abnormal betaglobin chain where valine replaces glutamic acid at the sixth position of the chain [5, 6]. In HbE, lysine replaces glutamic acid at position 26 of the beta-globin chain [6]. Sickle cell disease comprises a group of clinical disorders, which includes homozygous sickle cell anaemia (HbSS), sickle cell haemoglobin C (HbSC), sickle cell thalassaemia disease (HbSβ0, HbSβ+, HbS-alpha thalassaemia), sickle cell hereditary persistence of fetal haemoglobin (HbS-HPFH) and other compound heterozygous conditions [5]. When the intraerythrocytic conditions are right, sickle haemoglobin becomes relatively insoluble and forms a gel in a process of poly-

merisation. The carrier state of SCD, HbAS, is not usually associated with increased morbidity or mortality and is not included in the definition of sickle cell disease. In β-thalassaemia, there is absent or significant reduction in the synthesis of β-globin chain. This results in reduced amount of haemoglobin in circulation as well as imbalance in the amounts of the different globin chains. There is formation of α-tetramers (α4), increased amounts of fetal haemoglobin (α2γ2) and adult haemoglobin type 2 (HbA2, α2δ2). The α-tetramers interact and damage the red cell membrane leading to a haemolytic disease, in addition to the aplastic anaemia due to the ineffective erythropoiesis in the bone marrow in this condition. The α-thalassaemias are caused by the deletion of one or more of the four genes coding for the α-globin chain located on chromosome 16. There are excesses of γ-chains leading to formation of Bart’s haemoglobin (γ4) in the foetus; in postnatal life the excess β-globin chain leads to the formation of haemoglobin H (β4). In addition to the damages to erythrocyte cell membrane, there is reduction in the total circulating haemoglobin. Because of the abnormal globin proteins, both the haemoglobin molecules and the erythrocytes containing them are unstable and break down under predisposing conditions (erythrocyte hypoxia, acidosis, and hypertonicity, in the case of sickle cell disease) releasing free haemoglobin and oxygen radicals that lead to oxidative stress in the endothelium. This sets up a chronic inflammatory process in the vasculature and is thought to be the starting point of the many pathological processes observed. In SCD, the abnormal globin chain also causes the red blood cell to become less deformable and to stick more readily to the vascular endothelium. The downstream result is vaso-occlusion, leading to pain, ischaemia and infarction, which can occur anywhere in the body, including the bones, abdominal viscera and penile vasculature. Accelerated erythrocyte breakdown also leads to chronic haemolysis and a persistent state of anaemia in SCD and thalassaemia. Iron overload, especially in β-thalassaemia where chronic blood transfusion is almost always needed, is another complication with end-organ damage due to iron deposition. The laboratory tests required to make a diagnosis of haemoglobinopathy are described in . Table  7.1. An important part of the diagnostic process is having a high index of suspicion in at-risk populations. The possibility of an undiagnosed haemoglobinopathy should be actively considered in any child who could potentially require surgery.  

65 Haemoglobinopathies

Acute abdominal pain in children with SCD presents a significant diagnostic challenge. Painful vaso-occlusive crises can mimic surgical pathologies and are difficult to differentiate on clinical grounds [7]. Diagnosis is further compounded by the range of abdominal diseases seen in this population [8, 9]. Important differentials to consider are shown in . Table 7.2.

11]. It is the second most common cause of death in children with SCA under 10 years of age [11]. Acute hepatic sequestration is rarer (. Fig. 7.1). The pathophysiology of acute splenic sequestration remains unclear. Splenic outflow obstruction leads to massive sequestration of red cells, platelets and plasma in the spleen, often causing a significant decrease in circulating blood volume and a precipitous drop in haemoglobin concentration. Patients present with abdominal pain and distension, and signs of haemodynamic compromise. The diagnosis is based on evidence of acute splenic enlargement accompanied by a rapid decrease in the haematocrit, usually to half the patient’s ‘baseline’ value, as well as brisk reticulocytosis with increased nucleated red cells and moderate to severe thrombocytopaenia [5, 12]. Acute splenic sequestration crisis is a medical emergency, and treatment in the form of blood transfusion should be instigated rapidly to restore circulating volume and replenish red cell mass [5]. Adequate analgesia is also important. Patients who recover from the first episode of ASSC have a 50% chance of recurrences, especially if the first occurrence occurs at less than 1 year of age. Two possible management strategies can prevent this: children can be enrolled in a chronic blood transfusion programme or undergo a surgical splenectomy. There is no high-­ quality evidence to support one of these approaches over the other, and both are associated with potential and significant complications [13]. A concern following total splenectomy is infection, especially in children less than 5 years. So, partial splenectomy has been proposed as an alternative to preserve immune function. A recent case series showed that patients with SCD who underwent partial splenectomy were not subjected to increased rates of infection [14]. Nevertheless, a theoretical risk of sequestration in the splenic remnant still exists, so this approach needs further evaluation [13]. In the meantime, splenectomy should generally be reserved for selected patients with recurrent splenic sequestration crises or those who develop red cell alloantibodies following transfusion therapy. If a child less than 5 years of age were to receive splenectomy, vaccination against encapsulated organisms should be provided.

7.3.2  Acute Splenic Sequestration Crisis

7.3.3  Gallstone Disease

Acute splenic sequestration crisis is a life-threatening complication of SCD.  It mainly occurs in young children with HbSS who have not undergone autosplenectomy (infarction and fibrosis of the spleen) and older children with HbSC and HbSβ-thalassaemia, in whom the spleen may be less involved in autosplenectomy. It affects between 7% and 30% of children with HbSS [10,

Pigment gallstones are a frequent complication of sickle cell disease because continuous haemolysis leads to increased bilirubin excretion and subsequent stone formation [15, 16]. Although many children are asymptomatic, they can experience the full range of gallstone disease from biliary colic to cholangitis [16]. Management of the acute complications of gallstones is the same as in the general

..      Table 7.1  Laboratory investigations for the ­haemoglobinopathies

 

Investigations

Typical findings

Full blood count

Normocytic anaemia (SCD) Microcytic anaemiaa (thalassaemia/ HbSC)

Blood film

May show sickled erythrocytes, target cells and nucleated red cells in SCD; basophilic stippling is a nonspecific finding in some thalassaemias

Haemoglobin electrophoresis

Demonstrates a single band of HbS in SCA or HbS with another mutant haemoglobin in compound heterozygotes. A raised level of HbA2 is consistent with β-thalassaemia

Red cell staining

Reveals aggregates of β-globin protein in α-thalassaemia

Point-of-care rapid diagnosis

A few rapid screening tests are becoming available

DNA analysis

Often not required, but may be helpful in ascertaining the diagnosis of thalassaemia

Others

High-performance liquid chromatography and fluorescent in situ hybridisation test are used, when available, in the screening and confirmation of SCD

aIron

studies should be carried out to exclude iron deficiency

7.3  Surgical Manifestations of Sickle Cell

Disease

7.3.1  Acute Abdominal Pain

 

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G. O. Ogunrinde and R. Onalo

..      Table 7.2  Differential diagnoses of acute abdominal pain in sickle cell anaemia

7

Cause

Frequency

Characteristic features

Investigations

Vaso-­occlusive crises

Very common

May mimic acute surgical disease with guarding and distension; often attributed to ischaemia of mesentery and abdominal viscera

A specific cause is rarely identified

Biliary colic

Relatively common

Insidious-onset epigastric pain; subsides gradually

Pigment stones may be visible on a plain abdominal radiograph

Acute cholecystitis

Relatively common

Persistent right upper quadrant pain ± guarding; possibly fever

Ultrasound shows pericholecystic fluid and thickening of the gallbladder

Cholangitis

Uncommon

Persistent right upper quadrant pain ± guarding; fever and rigours; jaundice

Ultrasound shows dilatation of the common bile duct

Acute splenic sequestration

Common, occurring in up to 30% of patients

Left upper quadrant pain; acute splenic enlargement; hypovolaemic shock

Falling haemoglobin concentration, often with 2 g/dl drop below the baseline, thrombocytopaenia, and reticulocytosis

Acute sickle hepatic crisis

Common, affecting approximately 10% of patients

Right upper quadrant pain; low-grade fever; nausea; increasing jaundice; tender hepatomegaly

Mild to moderate elevation in liver transaminases, bilirubin levels generally less than 15 mg/dl (257 μmol/l)

Hepatic sequestration

Uncommon

Right upper quadrant pain; acute liver enlargement; hypovolaemic shock

Falling haemoglobin concentration, thrombocytopaenia, and reticulocytosis

Sickle cell intrahepatic cholestasis

Rare

Right upper quadrant or epigastric pain; acute liver enlargement; fever; nausea and vomiting

significant hyperbilirubinaemia

Viral hepatitis

Increased risk due to multiple transfusion and injections

Malaise; jaundice, low-grade fever; tender hepatomegaly

Elevated liver transaminases; positive viral serology

Pancreatitis

Increased risk due to pigment gallstones

Epigastric pain radiating through to the back; fever; nausea and vomiting

Raised amylase

Appendicitis

Less than in general population

Right iliac fossa pain ± guarding; nausea and vomiting; fever

Ischaemic colitis

Rare

Sudden onset of abdominal pain and distension; can pass bloody stool

Raised lactate

Urinary tract infection

Common

Dysuria, frequency, fever, suprapubic abdominal pain, flank pain

Positive nitrite dipstick test, positive culture

population, and elective cholecystectomy is recommended in patients with symptomatic cholelithiasis. The management of asymptomatic gallstones is less clear, but many would advocate cholecystectomy to avoid subsequent difficulty in distinguishing acute cholecystitis from vaso-occlusive painful episodes [17].

7.3.4  Orthopaedic Manifestations

Bone-related symptoms are the most common reason  for children with SCD to present to hospital [18]. The osteoarticular manifestations of SCD can be classified as acute or chronic, as shown in 7 Box 7.1.  

67 Haemoglobinopathies

..      Fig. 7.1  Acute liver enlargement should raise suspicion of hepatic sequestration crisis

Box 7.1  Osteoarticular Manifestations of Sickle Cell Disease Acute 55 Vaso-occlusive crises (including dactylitis and diaphyseal infarction) 55 Osteomyelitis 55 Septic arthritis 55 Pathological fractures Chronic 55 Avascular osteonecrosis 55 Osteoporosis 55 Osteomyelitis

7.3.4.1  Acute

In a child presenting with acute bone pain, the most important distinction to make is between bone ischaemia/infarction and bone infection. Although the vaso-occlusive crises that lead to bone infarction are up to 50 times more common than osteomyelitis, there is a potential for extensive damage to the bone and surrounding structures as well as overwhelming sepsis if an infection remains untreated.

It is difficult to distinguish between the two conditions on clinical criteria alone because the archetypal features of osteomyelitis—namely, pain, swelling and fever—are also common in vaso-occlusive crises [18]. A history of a painful episode that has lasted longer than 1–2 weeks or pain in a distribution that does not conform to previous painful crises should raise suspicions of an alternative underlying cause. Infection is not the only differential; stress fractures should also be considered. Both vaso-occlusive crisis and osteomyelitis are most common in the long bones of the arms and legs but can involve any part of the skeleton. Dactylitis, with swelling of the hands or feet, occurs in young children between the ages of 6 months and 4 years and can be one of the earliest signs of SCD.  Careful examination should be made for evidence of a draining sinus or bony deformity, which would suggest chronic or subacute bone infection. Adjacent joints should be assessed for evidence of an effusion, and the range and ease of movement noted. Preliminary laboratory investigations are often unhelpful in distinguishing infection from infarction because both conditions can cause a leucocytosis with raised inflammatory markers. Blood cultures taken before the commencement of antibiotics can be invaluable, as can culture of a bone or joint aspirate if there is evidence of fluid accumulation [18]. Imaging investigations are also confounded by the similarity between the radiographic appearances of bony infarction and infection [18]. Plain radiographs can be normal in the early stages of both conditions, and the periostitis and osteopaenia seen in acute osteomyelitis can also occur in vaso-occlusion. The imaging modality of choice for suspected osteomyelitis is magnetic resonance imaging (MRI), where it is available, but even this is not 100% specific for differentiating infection from infarction. Ultrasonography, which is showing a promise in the diagnosis of osteomyelitis in children, should be used to guide any aspiration procedures. The management of vaso-occlusive crises is largely supportive, focusing predominantly on pain management. By contrast, the first-line management of osteomyelitis requires urgent parenteral antibiotics, ideally directed at whatever organism has been isolated. When antibiotics are being started empirically, it is important to bear in mind that patients with SCD are more predisposed than the general population to contracting Salmonella osteomyelitis. Other organisms that cause bone infection in this population include Staphylococcus aureus, Haemophilus influenzae and Escherichia coli. Third-generation cephalosporins are often used in this setting, and treatment should continue for at least 6 weeks.

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[25]. The reason for this remains unclear, but children found to have a UTI should undergo the same careful urological evaluation as children with normal haemoglobin [26]. Priapism is a well-recognised complication of SCD and can be challenging to manage [27, 28]. The condi7.3.4.2  Chronic tion involves prolonged and painful penile erection, Avascular osteonecrosis is the most common chronic which can lead to irreversible fibrosis and impotence if it complication of sickle cell bone disease and is believed persists. About 90% of cases lasting longer than 24  h to affect up to 41% of these patients [19, 20]. It occurs have been associated with subsequent erectile dysfuncwhen repeated bone infarction leads to destruction and tion. Priapism occurs most commonly in children aged breakdown of an area of bone, and it most often occurs 5–13 years (and in adults aged 21–29 years) and affects at the femoral head. Other areas affected include the 28% of the male pediatric sickle population. Majority head of the humerus, the knee and the small joints of of children presenting with priapism have sickle cell disease [27–29]. the hands and feet. The most important history to obtain in a patient Sufferers describe pain and limited movement at the affected joint; examination may reveal localised tender- presenting with priapism pertains to the duration of the ness, with restriction of both active and passive joint current episode and to previous episodes and their treatmovements. Initial investigations should include a plain ment. Alternative causes of priapism, including trauma, radiograph, which may be diagnostic in more advanced drugs and malignancy, should be excluded [28]. Examination generally demonstrates rigid corpora cases, showing flattening or collapse of the articular surfaces and subchondral radiolucency. Less advanced cavernosa with a soft glans penis and corpus spongiocases may show evidence of sclerosis. MRI is the second-­ sum [28]. Involvement of the glans can suggest corporeal infarction. line investigation of choice. Investigations should seek to establish or exclude the When considering treatments for avascular necrosis in patients with SCD, it is important to note the differ- diagnosis of a haemoglobinopathy in all cases of priapism ences between this population and patients with normal if this is not already known. Many centres recommend haemoglobin with the same condition. Not only is the blood gas analysis of blood aspirated from the corpus cavpathophysiology of osteonecrosis in SCD thought to ernosum to exclude non-ischaemic causes of priapism differ from that of osteonecrosis from other causes, but [28]. Compared to the ischaemic, low-flow priapism, most the quality of the surrounding bone is often much typically in SCD, non-ischaemic priapism is a high-flow poorer in this group of patients [18]. Combined with state with causes that include cavernous artery fistulas. It their increased anaesthetic risk, this makes SCD patients is normally relatively pain-free and will often resolve without treatment. In ischaemic priapism, aspirated cavernoless attractive surgical candidates. A lack of quality data currently precludes any defini- sal blood is expected to appear dark in colour with an tive recommendations for the surgical management of oxygen saturation of less than 4 kPa (30 mm Hg) and a avascular necrosis in patients with SCD [21]. The available pH 10  days are associated with a significant increase in CVC-related infection [36, 37]. Particularly susceptible patients include those with burns and neutropenia [34] and those in whom sepsis poses a particular risk, e.g., a prosthetic heart valve in situ [38]. Antibiotic flushing of lumens decreases colonization but increases microbial drug resistance. Vancomycin locking is associated with a significant rate of development of vancomycin-resistant enterococcus (VRE) [39]. Heparin infusions have been shown to decrease rates of mechanical complications and possibly CLABSI [38]. There is no association between the site of insertion and the risk of CVC-related infection in children [15, 33]. Staff who are responsible for the insertion and maintenance of CVCs should be trained and educated in the insertion and care of these devices. 9.5.6.3  Thrombosis

The presence of a CVC is the most important risk factor in the development of deep vein thrombosis and venous thromboembolism (VTE) in children. It has been reported that >90% of VTE in neonates and >50% of VTE in older children are associated with a CVC [39]. The incidence of CVC-related thrombosis in children varies from 8% to 35% [11]. CVCs trigger thrombosis because of [11, 20]: (a) Vessel wall damage at the insertion site (b) Obstruction to the flow, causing stasis (c) Irritation of the vessel wall by the infusate (d) The presence of a foreign surface in a vessel The incidence of new thrombus formation decreases after 4 days, possibly because of reepithelialization of the injured vessel wall. CVCs that are placed in the subclavian and femoral veins have a similar incidence of thrombosis, although femoral thrombi are more likely to be symptomatic. In the case of subclavian vein cannulation, trauma from kinking of the vessel against the cannula as it is pinched between the clavicle and the first rib with arm movement may be a contributing factor. The cannulated femoral vein may be similarly affected, as the vessel is compressed onto the cannula when leg movement kinks the vessel under the inguinal ligament [20]. The degree of vessel occlusion by a catheter predisposing to thrombosis is directly related to the size of the catheter relative to vessel diameter [40, 41]. Multiple insertion attempts will cause greater vessel wall damage, leading to an increased risk of thrombus ­formation. This has been correlated with operator experience. Operators with >50 insertions have 50% fewer complications than less experienced operators [42]. The use of continuous heparin infusions (50–100 IU/ kg/day) to prevent thrombosis or to prolong the use of CVCs in children has been shown to be safe and effec-

tive [6, 42, 43, 44]. In summary, the risk of CRT may be reduced by (Janik 2004): 55 Cannulating the internal jugular vein 55 Choosing the smallest appropriate heparin-bonded catheter 55 Running a heparin infusion post-insertion 55 Removing the catheter as soon as it is no longer required 9.5.6.4  Malposition

Malposition is any tip position other than in the superior or inferior vena cava. Placement or migration of the catheter tip into the right atrium may cause cardiac arrhythmias or myocardial erosion. Damage to the wall of the superior vena cava and leakage of fluid into the pericardial space resulting in tamponade have also been reported. Catheters in the right atrium may be associated with thrombus formation and valvular damage. If the tip is not in a large vessel (and blood cannot be aspirated freely), there is a substantial risk of thrombosis and perforation with extravasation into the pericardial or pleural space. 9.5.6.5  Obstruction of Catheter

Obstruction of the central venous cannula can be caused by administration of incompatible mixtures that form debris. Also, the CVC should be flushed after withdrawal of blood, and care should be taken to keep the CVC open by continuous flow of infusion. If the CVC is not in use, it should be “packed” with a heparin solution [45]. If the CVC is blocked, it can sometimes be opened by flushing with normal saline with a small (2-ml) syringe. Although this manoeuver can be successful, it may result in rupture of the CVC. 9.5.6.6  Pinch-Off

The term “pinch-off ” refers to entrapment of subclavian catheters between the clavicle and the first rib. Over time, repeated compression causes catheter fracture, resulting in extravasation of fluids, or catheter breakage and embolization. 9.6  Conclusion

From the authors’ experience, the most common indications for insertion of central lines in children are (a) congenital intestinal anomalies, including gastroschisis, in neonates and (b) extensive burns, high-output enterocutaneous fistula, and difficult peripheral venous access in older children. The children most vulnerable to complications are the neonates and young infants. The lack of untrained staff and the lack of appropriate type of catheter for each situation pose the greatest challenge in the African context. Reliance on the peripheral line in most contexts within sub-Saharan Africa remains the most rational and pragmatic approach.

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J. K. M. Nyagetuba and E. N. Hansen

9.6.1  Ethical Issues

Key Summary Points

While few, if any, ethical issues exist when considering vascular access in a developing world context, the acquisition, insertion, and maintenance of central venous catheters may present financial and systemic hurdles that are too high to be sustainable. 9.7  Evidence-Based Research (.

 

Table 9.3)

..      Table 9.3  A randomized controlled trial of heparin vs. placebo infusion in peripherally placed central venous catheters in neonates Title

9

A Randomized Controlled Trial of Heparin versus Placebo Infusion to Prolong Usability of Peripherally Placed Percutaneous Central Venous Catheters (PCVCs) in Neonates: The HIP (heparin infusion for PCVC) study

Authors

Shah PS, Kalyn A, Satodia P, Dunn MS, Parvez B, Daneman A, Salem S, Glanc P, Ohlsson A, Shah V

Institution

4 tertiary NICUs in Ontario, Canada

Reference

Pediatrics. Vol 119:1, Jan 2007, e255–r291

Problem

Is heparin effective in prolonging the usability of PCVCs in neonates?

Study design

Randomized controlled trial

Study population

Neonates requiring PCVC that did not have grade ¾ IVH, recent onset of presumed/confirmed sepsis, bleeding diathesis, DIC, thrombocytopenia, arrhythmia, or pre-existing liver disease

Intervention

Heparin infusion of 0.5 U/kg/h

Primary outcome

Duration (hours) of catheter use

Results

201 neonates (heparin group, n = 100; control group, n = 101) were enrolled. Catheter duration was longer in the heparin group

Complications

One heparin patient developed thrombocytopenia but had negative HIT-antibody test

Conclusions

Heparin infusion prolonged the duration of peripherally inserted central venous catheter usability, which permitted a higher percentage of neonates to complete therapy without increasing adverse effects

1. Virtually every child will need vascular access. 2. Maximum flow is achieved with catheters that are wide and short. 3. The umbilical vein can be used for up to 2 weeks in neonates for administration of colloids or crystalloids and for exchange blood transfusion. 4. The intraosseous space is a rich, non-collapsible venous network. 5. The internal jugular vein, subclavian vein, and femoral vein are suitable for central venous access. 6. Common complications of vascular access include hemorrhage, line infection, and thrombosis.

References 1. Hansen AR, Greene A, Puder M.  Vascular access. In: Hansen AR, Puder M, editors. Manual of neonatal surgical intensive care. Hamilton/Lewiston: BC Decker Inc; 2003. p. 117–29. 2. Meegan ME, Conroy RM, Ole Lengeny S, et al. Effect on neonatal tetanus mortality after a culturally-based health promotion programme. Lancet. 2001;358:640–1. 3. Herlihy JM, Shaikh A, Mazimba A, et  al. Local percep tions, cultural beliefs and practices that shape umbilical cord care: a qualitative study in Southern Province. Zambia PLOS. 2013;8(11):1–14. 4. Khan EA, Correa AG, Baker CJ.  Suppurative thrombophlebitis in children: a ten year experience. Pediatr Infect Dis J. 1997;16(1):63–7. 5. McGee DC, Gould MK.  Preventing complications of central venous catheterization. N Engl J Med. 2003;348(12):1123–33. 6. Sznajder JI, Zveibil FR, Bitterman H, et al. Central vein catheterization. Failure and complication rates by three percutaneous approaches. Arch Intern Med. 1986;146(2):259–61. 7. Veenstra DL, Saint S, Saha S, et  al. Efficacy of antiseptic-­ impregnated central venous catheters in preventing catheter-­ related bloodstream infection: a meta-analysis. JAMA. 1999;281(3):261–7. 8. Mansfield PF, Hohn DC, Fornage BD, et  al. Complications and failures of subclavian-vein catheterization. N Engl J Med. 1994;331(26):1735–8. 9. Elliott TS, Faroqui MH, Armstrong RF, Hanson GC. Guidelines for good practice in central venous catheterization. Hospital Infection Society and the Research Unit of the Royal College of Physicians. J Hosp Infect. 1994;28(3):163–76. 10. Raad II, Hohn DC, Gilbreath BJ, et  al. Prevention of central venous catheter-related infections by using maximal sterile barrier precautions during insertion. Infect Control Hosp Epidemiol. 1994;15(4 Pt 1):231–8. 11. Gray RM. The where, what and how of paediatric central venous access. South Afr J Anaesth Analg. 2012;18(5):249–53. 12. Rupp SM, Apfelbaum JL, Blitt C, et  al. Practice guidelines for central venous access: a report by the American Society of Anesthesiologists Task Force on Central Venous Access.

99 Vascular Access in Children

American Society of Anesthesiologists Task Force on Central Venous Access. Anesthesiology. 2012;116(3):539–73. 13. Polderman KH, Girbes AJ. Central venous catheter use. Part 1: mechanical complications. Intensive Care Med. 2002;28(1):1–17. 14. Casado-Flores J, Barja A, Martino R, et  al. Complications of central venous catheterization in critically ill children. Pediatr Crit Care Med. 2001;2(1):57–62. 15. García-Teresa MA, Casado-Flores J, Delgado Dominquez MA, et  al. Infectious complications of percutaneous central venous catheterization in pediatric patients. Intensive Care Med. 2007;33(3):466–76. 16. Sheridan RL, Weber JM. Mechanical and infectious complications of central venous cannulation in children: lessons learned from a 10-year experience placing more than 1000 catheters. J Burn Care Res. 2006;27(5):713–8. 17. Deshpande KS, Hatem C, Ulrich AL, et  al. The incidence of infectious complications of central venous catheters at the subclavian, internal jugular, and femoral sites in an intensive care unit population. Crit Care Med. 2005;33(1):13–20. 18. Casado-Flores J, Valdivielso-Serna A, Perez-Jurado L, et  al. Subclavian vein catheterisation in critically ill children: an analysis of 322 cannulations. Intensive Care Med. 1991;17(6):350–4. 19. Male C, Chait P, Andrew M, et al. Central venous line-related thrombosis in children: association with central venous line location and insertion. Blood. 2003;101(11):4273–8. 20. Male C, Julian JA, Massicote P, et al. Significant association with location of central venous line placement and risk of venous thrombosis in children. Thromb Haemost. 2005;94(3):516–21. 21. Davis J, Surendran T, Thompson S, Corkey C. DKA, CVL and DVT.  Increased risk of deep vein thrombosis in children with diabetic ketoacidosis and femoral central venous lines. Ir Med J. 2007;100(1):344. 22. Gutierrez JA, Bagatell R, Sampson MP, et  al. Femoral central venous catheter associated deep vein thrombosis in children with diabetic ketoacidosis. Crit Care Med. 2003;31(1):80–3. 23. Worly JM, Fortenberry JD, Hansen I, et al. Deep venous thrombosis in children with diabetic ketoacidosis and femoral central venous catheters. Pediatrics. 2004;113(1:1):e57–60. 24. Asnes RS. Septic arthritis of the hip: a complication of femoral venipuncture. Pediatrics. 1966;38(5):837–41. 25. Sterner S, Plummer DW, Clinton J, Ruiz E.  A compari son of the supraclavicular approach and the infraclavicular approach for subclavian vein catheterization. Ann Emerg Med. 1986;15(4):421–4. 26. Arrighi DA, Farnell MB, Mucha P Jr, Iistrup DM, Anderson DL. Prospective, randomized trial of rapid venous access for patients in hypovolemic shock. Ann Emerg Med. 1989;18(9):927–30. 27. Merrer J, De Jonghe B, Golliot F, Lefrant JY, Raffy B, Barre E, Rigaud JP, Casciani D, Misset B, Bosquet C, Outin H, Brun-­ Buisson C, Nitenberg G, French Catheter Study Group in Intensive Care. Complications of femoral and subclavian venous catheterization in critically ill patients: a randomized controlled trial. JAMA. 2001;286(6):700–7. 28. Eisen LA, Narasimhan M, Berger JS, Mayo PH, Rosen MJ, Schneider RF. Mechanical complications of central venous catheters. J Intensive Care Med. 2006;21(1):40–6. 29. El Daba AA, Amr YM, Alhafez AA, Hashish A.  Ultrasonic guided insertion of central venous catheter in infants and children. Ann Pediatr Surg. 2010;6(3):136–9.

30. Verghese ST, McGill WA, Patel RI, Sell JE, Midgley FM, Ruttimann UE.  Ultrasound-guided internal jugular venous cannulation in infants: a prospective comparison with the traditional palpation method. Anesthesiology. 1999;91(1):71–7. 31. Milling TJ Jr, Rose J, Briggs WM, Birkhahn R, Gaeta TJ, Bove JJ. Randomized, controlled clinical trial of point-of-care limited ultrasonography assistance of central venous cannulation: the Third Sonography Outcomes Assessment Program (SOAP-3) Trial. Crit Care Med. 2005;33(8):1764–9. 32. Skippen P, Kissoon N.  Ultrasound guidance for central vascular access in the pediatric emergency department. Pediatr Emerg Care. 2007;23(3):203–7. 33. Pratt RJ, Pellow CM, Wilson JA, et al. Epic2: national evidence-­ based guidelines for preventing healthcare-associated infections in NHS hospitals in England. J Hosp Infect. 2007;65(Suppl 1):S1–S64. 34. Chaiyakunapruk N, Veenstra DL, Lipsky BA, Saint S.  Chlorhexidine compared with povidone-iodine solution for vascular catheter-site care: a meta-analysis. Ann Intern Med. 2002;136(11):792–801. 35. Maki DG, Band JD. A comparative study of polyantibiotic and iodophor ointments in prevention of vascular catheter-related infection. Am J Med. 1981;70(3):739–44. 36. Gray RM.  Audit of 104 consecutive central venous cathe ters placed in Red Cross Children’s Hospital operating suites. Unpublished; 2008. 37. Pierce CM, Wade A, Mok Q.  Heparin-bonded central venous lines reduce thrombotic and infective complications in critically ill children. Intensive Care Med. 2000;26(7):967–72. 38. O’Grady NP, Alexander M, Dellinger EP, et  al. Guidelines for the prevention of intravascular catheter-related infections. Pediatrics. 2002;110(5):e51. 39. Parasuraman S, Goldhaber SZ.  Venous thromboembolism in children. Circulation. 2006;113(2):e12–6. 40. Beck C, Dubois J, Grignon A, et  al. Incidence and risk factors of catheter- related deep vein thrombosis in a pediatric intensive care unit: a prospective study. J Pediatr. 1998;133(2): 237–41. 41. Janik JE, Conlon SJ, Janik JS. Percutaneous Central Access in Patients Younger than 5 years: Size Does Matter. J Pediatr Surg. 2004;39(8):1252–56. 42. Talbott GA, Winters WD, Bratton SL, O’Rourke PP. A prospective study of femoral catheter-related thrombosis in children. Arch Pediatr Adolesc Med. 1995;149(3):288–91. 43. Abdelkefi A, Ben Othman T, Kammoun L, et al. Prevention of central venous line-related thrombosis by continuous infusion of low-dose unfractionated heparin, in patients with haemato-­ oncological disease. A randomized controlled trial. Thromb Haemost. 2004;92(3):654–61. 44. Shah PS, Kalyn A, Satodia P, et  al. A randomized controlled trial of heparin versus placebo infusion to prolong the usability of peripherally placed central venous catheters (PCVCs) in neonates: the HIP (heparin infusion for PCVC) study. Pediatrics. 2007;119(1):e284–91. 45. Hentschel R, Wiescholek U, von Lengerke J, et al. Coagulation-­ associated complications of indwelling arterial and central venous catheters during heparin prophylaxis: a prospective study. Eur J Paediatr. 1999;158(Suppl 3):S126S–129.

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Anaesthesia and Perioperative Care Mark Newton, Olamide O. Dairo, and Stella A. Eguma Contents 10.1

Introduction – 102

10.2

Differences in Anatomy and Physiology – 102

10.2.1 10.2.2 10.2.3 10.2.4 10.2.5

 ardiovascular Function – 102 C Respiratory Function – 102 Renal Function – 103 Temperature Regulation – 103 Haematology – 103

10.3

Preoperative Assessment and Preparation – 103

10.3.1 10.3.2

F asting Guidelines – 104 Premedication – 104

10.4

Anaesthetic Management – 104

10.4.1 10.4.2

I nduction of Anaesthesia – 104 Maintenance of Anaesthesia – 105

10.5

Airway Management – 105

10.5.1 10.5.2 10.5.3 10.5.4

 irway Maintenance Equipment – 105 A Mask Ventilation – 107 Laryngoscopy and Intubation – 108 Muscle Relaxants – 109

10.6

Monitoring – 110

10.7

Narcotics – 110

10.8

Regional Anaesthesia – 110

10.9

Postoperative Care – 111

10.10 Perioperative Anaesthesia Complications – 112 10.11 Evidence-Based Research – 112 References – 113

© Springer Nature Switzerland AG 2020 E.A. Ameh et al. (eds.), Pediatric Surgery, https://doi.org/10.1007/978-3-030-41724-6_10

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10.1  Introduction

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The practice of providing surgical anaesthesia for children dates back to 1842, when Dr. Crawford Long used ether for an amputation on an 8-year-old boy [1]. Since that event, many pediatric patients have been administered anaesthesia with ether. Today, however, essentially all the anaesthetic drugs used in the adult population are used in the pediatric population. Major steps forward— such as the use of endotracheal intubation (1936), the Jackson-Rees modification of the T-piece (1950), the precordial stethoscope (1953), the use of muscle relaxants (1940s), and the introduction of the newer inhalation anaesthetic agents (1960s)—have allowed the administering of anaesthesia to become safer [2]. Today despite ongoing challenges, anaesthesia is provided for the pediatric patient routinely in many hospitals throughout the world. In Africa, for example, the pediatric patient presents for surgery with a pathophysiological picture that can be very different from that of a similar patient in the typical Western hospital setting. The addition of malnutrition, tropical diseases such as tuberculosis and malaria, delayed presentation, poor primary care, and chronic disease states can compound the acute surgical problem that is prompting intervention [3]. In many African settings, the basic hospital infrastructure, theatre supplies, and essential monitoring equipment—all of which make pediatric anaesthesia safer—are commonly unavailable. Anaesthesia supplies appropriately sized for neonates and small children, such as endotracheal tubes, blood pressure cuffs, and even small syringes that allow for safer dose titration, are not available in many hospitals [4]. These issues, as they relate to providing safe anaesthesia care for neonates and pediatric patients who require surgery in the African setting, challenge even the most skilled anaesthesia care providers. This chapter provides an overview of some of the challenges when providing anaesthesia care for children in Africa. The chapter reviews the cardiac, respiratory, and renal differences of children in comparison with adults. Additionally, it addresses preoperative assessment, including guidelines for nothing by mouth (NPO, or nil per os), general and regional anaesthesia, intraoperative monitoring, airway management, and postoperative care.

10.2  Differences in Anatomy

and Physiology

10.2.1  Cardiovascular Function

Neonatal myocardial function demonstrates a limited ability to increase cardiac output by increasing the stroke volume. The neonate’s cardiac output is thus

more dependent on heart rate [5]. The neonate cardiac muscle also has fewer contractile elements per gram of tissue when compared to an adult heart, which compromises the neonate’s ability to respond to volume loading with an increase in cardiac output. In addition, the parasympathetic nervous system is more developed than the sympathetic nervous system until the age of 6 months, when the two systems become more balanced. This imbalance in the autonomic nervous system in the neonate predisposes the neonate to bradycardia during times of stress, even with simple airway suctioning, and certainly during airway intubation attempts. This difference between the neonate and the adult is evident during times of hypovolaemia, such as intestinal obstruction, many neonatal emergencies, and delayed medical management for many surgical cases because neonates cannot increase their heart rates sufficiently to overcome the decrease in stroke volume. Congenital heart disease (CHD) is common in the neonatal surgical patient in comparison with the normal population. Many congenital surgical problems have associated cardiac anomalies; therefore, any neonate presenting for surgery needs to have an appropriate cardiac exam. If a murmur is present, then a further work-­up may be indicated prior to surgical intervention, and anaesthetic adjustments must be made in an effort to maximize the oxygen delivery and blood pressure. A chest X-ray and oxygen saturation determination will help to determine the need for further specialized work-­up if available. The need for antibiotic coverage perioperatively should be considered in all patients with a cardiac defect. Currently, an antibiotic given preoperatively either 60 minutes orally or 30 minutes intravenously (IV) will cover the risk of endocarditis [5]. 10.2.2  Respiratory Function

The neonatal airway is narrowest at the cricoid cartilage and not at the vocal cords, as in the adult. Also, the glottis is more anterior, with the epiglottis being less rigid, which tends to occlude the airway opening when attempting an intubation. All of these anatomical differences between a neonate and an adult can result in a more difficult intubation when attempting to place the endotracheal tube, but with a skilled anaesthesia care provider, this also can become routine. The induction and intubation of a neonate requires special care because the oxygen saturation will decrease much faster than in an adult patient due to the higher neonatal oxygen consumption (2×) and low functional residual capacity (FRC) in the neonate [6]. A premature infant will have an immature chemoreceptor ventilatory drive and at times slow respiratory effort with an elevation in carbon dioxide levels. For many premature infants,

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apnoea, which is cessation of ventilation for 20 seconds with bradycardia, can be a serious postoperative problem that needs careful monitoring. 10.2.3  Renal Function

The newborn’s immature renal function can contribute to many fluid and electrolyte problems in the surgical patient. Glomerular filtration rates (GFRs) reach adult levels by 1  year of age, and the newborn’s inability to concentrate urine certainly affects the ability of the newborn to respond to hypovolaemia. The infant’s inability to balance sodium levels appropriately prompts careful attention to the balance of sodium because the renal system’s immaturity results in an overall sodium loss. 10.2.4  Temperature Regulation

Temperature regulation differences result in the newborn having hypothermic periods in the perioperative period. The infant’s relatively large surface area, inability to shiver, large head size (related to heat loss), and poor insulation can cause dangerously low temperature levels, which can cause hypoventilation and even cardiac arrhythmias [6]. The room temperature for the newborn needs to be closely monitored; in areas where the outside environment has more impact on the theatre temperature, warming pads and even small heating units may be utilized to maintain the patient’s body temperature. The use of the type of heating pad that can be purchased in most African capital cities needs to be monitored in the theatre setting, as this pad can cause burns in the neonate if the controls and the patient’s temperature are not monitored diligently. Also, the use of warmed fluids at appropriate levels needs to be considered in any theatre where pediatric surgery is more common. 10.2.5  Haematology

The red blood cells in the newborn are very different from those of adult haemoglobin because fetal haemoglobin dominates, and at 6–8 months of age, this subunit of haemoglobin is absent. Fetal haemoglobin has a higher affinity for oxygen; hence, the oxygen-­carrying capacity is higher [7]. Many pediatric patients in the African setting may present for surgery with relative anaemia, and some may need further investigations. Although nutritional causes of anaemia need to be considered first, there are many other potential causes, such as malaria, sickle cell disease, intestinal worms, and even drug-induced anaemias. Many pediatric patients can have elective surgery when their haemoglobin is less

than 8 g/dl, but these patients will have a better postoperative course with supplemental oxygen. In the context where sickle cell haemoglobin analysis is not available, blood is given to sickle cell disease patients who present for surgery with a haemoglobin level below 8 g/dl. 10.3  Preoperative Assessment

and Preparation

The emotional stress evident in the eyes of pediatric patients and their parents in the preoperative setting prompts one to make every effort to alleviate this aspect of the anaesthesia and surgical experience. The preparation by the anaesthesia care provider should include a preoperative visit at which the provider determines the need for surgery, the physiological implications for anaesthesia, the necessary laboratory evaluations, and the psychological condition of the patient and family. If this is done in advance, and all questions by the family as well as the surgical team are answered, then the overall care of the pediatric patient will improve. The patient may benefit from a preoperative sedative or other medication so that the transfer from floor care to the theatre care can be smoother. Psychological factors, which include the patient’s age, the cultural norms for surgery, the impact of previous medical care prior to the patient arriving at the institution, and the pathophysiological condition of the patient, all impact the preoperative preparation. Children between the ages of 6  months and 5  years tend to demonstrate the most fear when presenting to the theatre setting. A carefully arranged preoperative environment that can help with these fear issues may allow for easier transfer to the operating theatre. Also, a good physical exam that includes the cardiorespiratory system, nervous system, and gastrointestinal system will allow the anaesthesia care provider the opportunity to develop an anaesthesia plan that is more informed and safe. Disorders of the central nervous system (CNS) are common in the pediatric patient; trauma—which is very high in this population in every country in the world—can produce closed head injury patients who present in the acute and the chronic phases of trauma. Anticonvulsant medications for seizure disorders need to be evaluated for efficacy and severe side effects such as thrombocytopenia, aplastic anaemia, hepatotoxicity, and pancreatitis [8]. Cerebral palsy, neuromuscular diseases, and polio are all common aetiologies for which a pediatric patient presents for an orthopaedic procedure or an emergency surgery, and special care needs to be taken in the anaesthesia plan for such populations. The incidence of congenital cardiac diseases is more common in the pediatric surgical patient than it is in the

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general population. If a murmur is discovered in the preoperative work-up, it needs to be evaluated. Even a pulse oximetry reading that is normal rules out many intracardiac shunt lesions, which can be very helpful information for the anaesthesia plan. Respiratory problems, such as adenoid hypertrophy, cleft palate, upper airway infections, and asthma, are commonly seen in the surgical patient and add to the anaesthetic risks. Typically, if a patient presents with an acute productive cough, fever, or wheezing, then elective surgeries need to be cancelled for a minimum of 2 weeks to allow for resolution of the underlying infectious process and the corresponding airway effects. For the preterm infant, the incidence of apnoea and bradycardia increases the need for cardiorespiratory monitoring in the postoperative period for at least 12–24 hours, depending upon the severity of the problem. 10.3.1  Fasting Guidelines

10

The preoperative NPO guidelines for surgical procedures in the pediatric population are different from those for the adult population. Neonates and infants who are still nursing can have breast milk up to 4 hours pre-surgery. Children can have clear liquids up to 2 hours and solids (including formula) up to 6 hours before surgery. All children on diets with fatty foods need to wait 8 hours after a solid meal for elective surgery. Of course, emergency surgery cases need to proceed without consideration of the NPO status, and precautions should be taken to avoid pulmonary aspiration of gastric contents. The glucose status of a neonate who presents for surgery and has had an intravenous line needs close evaluation so that hypoglycaemia does not interfere with the anaesthesia management. 10.3.2  Premedication

The use of preanaesthetic medication to remove anxiety is common in the pediatric population. The use of anticholinergics, benzodiazepines, and narcotics can be adjusted by the anaesthesia care provider to produce the desired effect with weight-appropriate doses. There are risks involved in a setting with few nurses per patient population in the ward, as an elevated dose of the drug may be given inadvertently because the doses are small and early side effects may be difficult to detect. Premedication should be individualized to each patient based on age, weight, level of anxiety, previous anaesthetic experience, allergies, and expected level of cooperation. The oral route remains the commonest way of giving premedication. It has the advantage of being painless but may have an unpredictable onset

or a bitter taste. Midazolam, a short-acting water-soluble benzodiazepine, is widely used for premedication in pediatric practice. It has a fairly reliable onset and duration of action and can be given through a variety of routes, including oral, nasal, sublingual, rectal, intravenous, and intramuscular (IM). It does not appear to prolong recovery room stay or time to hospital discharge [9]. Other commonly used premedication drugs include fentanyl, ketamine, sufentanil, clonidine, and, recently, dexmedetomidine. Because some of these drugs are expensive, each institution needs to assess its drug availability and budget and then seek alternatives to these agents if they are not available. Premedication should be avoided in the patient with elevated intracranial pressure and carefully titrated in the patient with congenital heart disease. The generalities that are presented in this section prompt anaesthesia care providers and surgeons to carefully assess their specific clinical situations and then determine whether the use of premedication is safe and advantageous for their specific population of pediatric patients. 10.4  Anaesthetic Management

At the end of the preoperative assessment, an anaesthetic plan is made that takes into consideration the medical condition of the child, the needs of the proposed surgical operation, and a way of allaying any anxiety being felt by the parents and the child. All medications and materials, including blood and intravenous fluids, must be ready before induction begins. All equipment, including the anaesthetic machine, must be checked and confirmed to be working properly. Adequate preoperative preparation (including building rapport with the patient) and the rational use of premedication will facilitate safe and atraumatic induction of anaesthesia. 10.4.1  Induction of Anaesthesia

Like premedication, induction of anaesthesia should be tailored to the individual patient. The same factors used to determine suitable premedication come into play when choosing an induction method. Inhalational and intravenous routes of induction are more common than rectal and intramuscular routes, although ketamine can be used in the pediatric population when an IV line is not in place or not needed for a very short procedure such as a dressing change. Because of their fear of needles, inhalational induction is most common for children up to 10 years of age (and perhaps even well into the teenage years) who are undergoing elective surgery. This method is particularly

105 Anaesthesia and Perioperative Care

useful because inhaled anaesthetic drugs increase in concentration in the alveoli of children more rapidly than they do in adults [10]. Inhalational induction should be a slow, smooth process with care taken to keep the airway patent at all times. Sevoflurane is replacing halothane as the agent of choice because it appears to have fewer cardiovascular side effects and a reduced incidence of intraoperative complications like breath holding, cough, and laryngospasm while being faster in onset and recovery [11]. However, many anaesthesia care providers in developing countries may not have access to sevoflurane, and halothane will be the available agent. Halothane in the hands of a trained pediatric anaesthesia care provider will allow for a very smooth induction with the patient ventilating spontaneously, but very careful cardiac monitoring needs to be vigilantly performed. Intravenous induction is the method of choice when there is a pre-existing IV or when inhalational induction is contraindicated (e.g. in the event of trauma or any full stomach scenario). Thiopentone, ketamine, and propofol remain the main IV induction agents. Etomidate, when available, can also be useful. Intramuscular induction is often used in the older uncooperative child who cannot be reasoned with, such as a child with autism or mental retardation. In settings where resources are limited, intramuscular ketamine can be useful for very short procedures such as circumcision and wound debridement. If the patient is cooperative, monitors are applied before induction; otherwise, they are put on as early as possible during induction and kept on until the patient is fully awake. The use of a precordial stethoscope and, if available, a pulse oximeter can provide sufficient monitoring for the induction period, allowing one to assess the airway and cardiac system with limited monitoring equipment. 10.4.2  Maintenance of Anaesthesia

The anaesthetic may be continued by using inhalational agents, intravenous agents (including muscle relaxants and opioids), or a combination of these agents in a balanced technique. During this stage, the airway is kept patent by either a face mask, a laryngeal mask airway (LMA), or an endotracheal tube. 10.5  Airway Management

One of the greatest challenges in pediatric anaesthesia is the management of the airway, particularly in neonates. A combination of anatomical, physiological, and developmental factors conspires to make airway management in children more challenging than in adults [12]. Normal respiratory rates are 40 per minute in neonates and 20–30 per minute in infants.

Because of the small airway size, any decrease in diameter such as may occur from secretions, bronchoconstriction, compression, or oedema may lead to significant airway obstruction. Respiration is mainly diaphragmatic in infants; therefore any slight abdominal distention can compromise respiration. Oxygen consumption in the neonate is approximately 7  ml/kg per minute, as opposed to 3–4 ml/kg per minute in the adult. For infants and children, the higher oxygen requirements per kilogram produce hypoxia more rapidly when there is airway obstruction. Perioperative pediatric airway obstruction occurs commonly when the consciousness level is depressed and the airway is not properly positioned to maintain its patency [12]. 10.5.1  Airway Maintenance Equipment

Pediatric airway equipment is usually designed to minimize trauma, dead space, airway resistance, and rebreathing. Equipment for airway maintenance includes face masks (. Fig.  10.1), oropharyngeal and nasopharyngeal airways (. Fig. 10.2), breathing circuits and Ambu bags, laryngoscopes, endotracheal tubes, and laryngeal mask airways (LMAs).  

 

10.5.1.1  Face Masks

Face masks come in different sizes (00 for neonates, 0 for infants, 1 for small children, 2 for bigger children), shapes, and colours (see . Fig. 10.1). The neonatal face mask has minimal dead space and is designed to limit rebreathing. It must fit closely over the mouth and nose without obstructing the nares.  

10.5.1.2  Oropharyngeal Airways

These are used to improve patency of the upper airway and improve gas delivery to the lungs. They are usually the first intervention in cases of upper airway obstruction. Because they can worsen airway obstruction if the wrong size is used or if the patient is Stage 2, timing of insertion is extremely important. 10.5.1.3  Breathing Circuits

The Ayre’s T-piece breathing circuit (. Fig.  10.3) is used for children weighing less than 20 kg because it is a low-­resistance circuit. For children weighing more than 20 kg, an adult circuit (Bain or Magill) can be used. The Ayre’s T-piece can be used for both spontaneous and assisted ventilation.  

10.5.1.4  Laryngoscopes

The relatively high position and inclination of the larynx in infants make a straight laryngoscope blade (e.g. the Miller 0 (. Fig. 10.4) or the infant Magill) a good choice, whereas children older than 1  year of age can  

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10

..      Fig. 10.2  Oropharyngeal airways

10.5.1.6  Cuffed Endotracheal Tubes

..      Fig. 10.1  Face masks

generally be managed with curved blades like the size 2 Macintosh (. Fig. 10.5).  

10.5.1.5  Laryngeal Mask Airways

LMAs (. Fig. 10.6) are useful airway management tools. They are less traumatic than endotracheal tubes and do not require laryngoscopy to insert. They do not, however, protect against regurgitation and aspiration. Sizes 1, 1½, 2, 2½, and 3 can be used in children from 2  months to 12 years of age, according to the weight of the child. The LMA has proved its usefulness over the last 30 years and is now prominent in most difficult airway algorithms. Endotracheal tubes used for children younger than 6 years of age are usually uncuffed. . Table 10.1 provides a guide for choosing an appropriate endotracheal tube.  

 

Perhaps nothing illustrates better how rapidly changes in clinical practice occur than the issue of cuffed endotracheal tubes (ETTs). Until quite recently, it was orthodoxy that children required uncuffed ETTs. The infant cricoid cartilage is the narrowest part of the airway (in adults it is the glottis); thus the ability to pass an ETT through the infant glottis did not guarantee that the tube would not cause pressure-associated damage at the level of the cricoid cartilage (. Fig. 10.7). This damage could result in postoperative stridor which could be mildly symptomatic and require only observation, or be severe enough to require emergency treatment. Because of this concern, it was customary to ensure that an ETT in infants and small children passed easily through the glottis and developed a gas leak at 15–20 cmH2O pressure. A few recent developments have successfully challenged this view. MRI studies have shown that the cricoid ring is not circular but elliptical, with its anteroposterior diameter being greater than its lateral diameter. This means that pressure that the ETT exerts is not evenly distributed and although there may  

107 Anaesthesia and Perioperative Care

..      Fig. 10.3  Breathing circuits

be a leak around an uncuffed ETT, there may still be pressure against the fragile mucosa [13]. At the same time came the development of ETTs made of softer materials and with high-volume low-­ pressure cuffs. Cuffs are made of ultrathin (10 microns) polyurethane which allows an effective tracheal seal at pressures which are insufficient to cause tracheal mucosal pressure necrosis. In addition, these tubes typically lack a Murphy eye which allows the cuff to be located more distally on the ETT shaft, thus reliably placing the cuff below the cricoid ring and reducing the chance of an accidental mainstem intubation. Cuffed ETTs such as the Microcuff® (Kimberly-Clark, Dallas, TX) are being used even in neonates and small infants. The advantages of cuffed ETTs include fewer tube exchanges (for wrong size), better control of ventilation, better airway protection, and fewer complications (perioperative laryngospasm, postoperative stridor, and sore throat) [14].

..      Fig. 10.4  Laryngoscopes for infant

Cuffed ETTs are however not without their problems. Meticulous attention must be paid to the ETT cuff pressure. Some brands of cuffed pediatric ETTs are still of the low-volume high-pressure variety. In addition, the cuffs constitute enough bulk to traumatize the cricoid area if adequate care is not taken—especially if the manufacturer’s size recommendations are not followed [15]. 10.5.2  Mask Ventilation

Due to the neonate’s relatively large head, a small roll should be positioned under the shoulders to prevent hyperflexion of the head and align the axis of the

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..      Table 10.1  Guide for sizing endotracheal tubes Age

Size of endotracheal tube (mm)

Premature

2–2.5

Full-term newborn

3.0

6–12 months

3.5

1–2 years

4–4.5

>2 years

4.5 + [age (in years) ÷ 4]

Posterior

10

Thyroid cartilage

Anterior

Cricoid

..      Fig. 10.5  Laryngoscopes for children older than 1 year of age

Adult

Infant

..      Fig. 10.7  Narrowest part of the infant airway is the cricoid cartilage

mouth, pharynx, and larynx to allow for easy flow of air. For the older child, no pillow or roll is needed. An appropriately sized oropharyngeal airway can improve mask ventilation. 10.5.3  Laryngoscopy and Intubation

..      Fig. 10.6  Laryngeal mask airways

The airway should be ventilated in all but the shortest of procedures because the pediatric airway is very prone to obstruction during anaesthesia. For neonates and infants, a slight external pressure on the larynx helps to bring the glottis into view. A small leak should be allowed around an uncuffed tube to prevent oedema formation and postoperative airway obstruction, which may follow prolonged intubation. A gaseous induction using 100% oxygen with halothane (or sevoflurane if available) is the technique of choice in small children and those with difficult airways.

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The aim is to attain a plane of anaesthesia that is deep enough to allow laryngoscopy. Once the pupils become constricted and central, laryngoscopy and orotracheal intubation can be performed. Suxamethonium at a dose of 2 mg/kg can be used to facilitate intubation. Atropine (0.02  mg/kg) or glycopyrrolate (0.01  mg/kg) should be given to prevent bradycardia and to dry secretions. Both lungs should be auscultated for bilateral air entry after intubation, and the endotracheal tube should be secured firmly in position. Signs of respiratory obstruction include an increase in respiratory rate (>50 per minute in an infant and 30 per minute in a child); a ‘see-saw’ pattern of chest and abdominal breathing movements; flaring of the alar nasi; and the use of accessory muscles of respiration (sternomastoids, scalene muscles) resulting in suprasternal, intercostal, and subcostal retraction. In acute airway obstruction, for which one cannot intubate or ventilate, cricothyrotomy may be the only option. Cricothyrotomy is difficult in a small child and carries many risks. Where difficult tracheal intubation is anticipated, experienced help should be sought beforehand. There are fibre-optic laryngoscopes suitable for use in children, but this requires expertise and experience and is not an option in emergency airway obstruction. Gum elastic bougies which are available in adult and pediatric sizes are simple to use and are often very effective. The bougie is a rigid but malleable rubber device. It can be moulded or curved into a ‘hockey stick’ shape, for example, such that even if only the base of the glottis can be visualized, the short end of the hockey stick can still be passed blindly upwards into the trachea. Once the bougie has been placed into the trachea, an ETT can then be ‘railroaded’ over it. The bougie is then removed, leaving the ETT in the trachea.

..      Fig. 10.8  Videolaryngoscope view of the cords with approaching endotracheal tube

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The fibre-optic bronchoscope is still considered the gold standard in situations where securing the airway by direct laryngoscopy is not possible. However, it is expensive, fragile, and difficult to maintain and can be rendered useless when there is blood or secretions in the airway. Importantly, as mentioned above, it is a learned skill that requires practice and experience. Because of these potential obstacles, fibre-optic intubation can be very difficult to perform and may not be readily available. Video laryngoscopes (GlideScope® Verathon, Bothell, WA) attempt to combine the benefits of image-­ guided fibre-optic intubation with the ease of direct laryngoscopy (. Fig. 10.8). They are less fragile and more intuitive to use and do not require the oral, pharyngeal, and laryngeal axes to be aligned. They have also emerged as quite satisfactory teaching tools as the instructor has the same view as the trainee. However, unlike fibre-optic scopes they cannot be used for nasal intubation or positioning of a bronchial blocker or double-lumen tube. As the number of airway management devices continues to multiply, it may be best for each clinician to gain familiarity and expertise with a limited number of devices, rather than trying to be an expert in all.  

10.5.4  Muscle Relaxants

Muscle relaxants are used to facilitate tracheal intubation and provide muscle relaxation during surgery, thus permitting lighter planes of anaesthesia. They are used in intraperitoneal, intrathoracic, and intracranial procedures. Muscle relaxants are classified into depolarizing and non-depolarizing groups. Succinylcholine is the only depolarizing neuromuscular blocker in use today, and it remains the agent with the quickest onset and shortest duration of action. Unfortunately, succinylcholine is associated with some life-threatening side effects (hyperkalaemia, malignant hyperthermia), and its use has reduced somewhat in recent years. Non-depolarizing muscle relaxants are classified based on structure and mode of elimination. The benzylisoquinolines are atracurium, cisatracurium, and mivacurium, which may be available in some African urban centres. The first two are eliminated by Hofmann degradation and ester hydrolysis by nonspecific plasma esterases. Mivacurium is metabolized by plasma cholinesterase. The aminosteroids (pancuronium, vecuronium, and rocuronium) are metabolized in the liver, and their inactive end products are eliminated by the kidney.

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10.6  Monitoring

10

The purpose of monitoring is to measure physiological variables and to indicate trends of change, thus enabling corrective action to be taken. The anaesthetist remains the most important monitor and must remain in close contact with the patient during all aspects of the anaesthetic. The precordial (or oesophageal) stethoscope is an invaluable monitor for many pediatric anaesthetists. It provides a direct way to continuously monitor heart rate and rhythm as well as breath sounds; it allows early detection of changes in the rate and character of these sounds. The electrocardiogram (ECG) is useful for diagnosing rate-related arrhythmias, especially bradycardia and supraventricular tachycardia (SVT). The ECG is an index of electrical activity. A normal waveform may exist, however, in the presence of reduced cardiac output, so the ECG should be interpreted in the context of other information obtained from other monitors of the patient’s circulation. The patient’s circulation may be monitored by observation of the peripheral perfusion, peripheral pulse, blood pressure, urine output, and arterial oxygen saturation. Observation of the patient’s extremities yields information about the state of the patient’s circulation. When the skin is warm and dry all the way to the fingers and toes, one can infer that tissue perfusion and therefore cardiac output is adequate. Cool extremities thus indicate hypovolaemia and reduced cardiac output. Palpation of peripheral pulses is another way of obtaining the same information. As intravascular volume decreases, the pulse volume decreases, especially in the wrists and feet. Adequate production of urine implies adequate renal perfusion and probably adequate perfusion of other vital organs. Measurement of urine output is particularly indicated in critically ill or shocked patients or when massive fluid shifts are expected. A urine output of 0.75–1 ml/kg per hour is desirable. Blood pressure provides another indirect means of measuring circulating blood volume and cardiac output due to the relationship: Blood Pressure = Cardiac Output ´ Peripheral Resistance Methods of measuring blood pressure range from palpation and auscultation to direct intraarterial manometry. A pulse oximeter measures oxygen saturation continuously and thus provides another indirect assessment of the function of the circulatory system. Estimation of blood loss is a useful monitor in maintaining the overall integrity of the cardiovascular system. Apart from monitoring the patient’s colour, respiratory rate, and breathing pattern, auscultation of both lungs should be performed frequently. Airway pressure monitors and disconnection alarms are desirable in venti-

lated patients. A capnograph, when available, can be used to confirm correct placement of an endotracheal tube and to continuously assess the adequacy of ventilation. It is important to remember that monitors only provide information. It is the duty of the anaesthetist to interpret this information and then act appropriately. The postoperative pediatric patient needs close monitoring in the recovery room and wards especially when narcotics are used for surgical pain management. The vigilance of the nursing staff and anaesthesia care provider will decrease much of the morbidity and mortality associated with many pediatric and especially neonatal, surgical patients. 10.7  Narcotics

Opioids can be titrated for intraoperative and postoperative analgesia, and to provide a smooth awakening from anaesthesia. All the commonly used opioids are used in pediatric practice, and, just as in adults, in high doses they all carry the risk of respiratory depression. Fear of this respiratory depression is not a reason to deny children the benefits of opioid pain relief. Careful titration to effect will often eliminate this complication. 10.8  Regional Anaesthesia

Regional anaesthesia (RA) is particularly suited to patients undergoing outpatient procedures and peripheral surgery. It has also been suggested that RA may improve pulmonary function in patients who have had thoracic or upper abdominal surgery [16]. Advantages include the reduced need for deeper planes of general anaesthesia in patients who have had a nerve block to supplement their general anaesthesia (GA). RA also allows a painfree awakening while minimizing or avoiding the use of opioids altogether. In addition, there is often early ambulation and excellent postoperative analgesia. The use of RA, however, has certain limitations in pediatric practice. Except in the older child and adolescent, blocks are rarely performed in the awake child and usually need to be part of a combined technique. Regional anaesthetic techniques are particularly useful in children at risk for malignant hyperthermia or in those for whom it is necessary to preserve what little respiratory reserve they have (e.g., children with cystic fibrosis, severe asthma, or neuromuscular disorders). The two classes of local anaesthetics—esters and amides—exhibit differences in distribution and metabolism in pediatric patients (especially neonates) when compared to adults. Awareness of these pharmacokinetic differences leads to safer use in this vulnerable patient population.

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..      Table 10.2  Maximum recommended doses of local anaesthetics Local anaesthetic

Maximum dose (mg/kg)

2-Chloroprocaine

20

Lidocaine

7

Mepivacaine

7

Bupivacaine

2.5

Ropivacaine

3.5

Tetracaine

1.5

Ester local anaesthetics are metabolized by plasma cholinesterase, which has lower activity levels in neonates and infants up to the age of 6 months. This may theoretically lead to prolonged effects, but in practice, the effects of 2-chloroprocaine given for continuous caudal anaesthesia have been shown not to be prolonged, even when using relatively high infusion rates [17]. In fact, in spite of the low plasma cholinesterase activity, plasma chloroprocaine levels remained low. Amides are bound by plasma proteins and metabolized by the liver. Neonates have reduced plasma protein concentrations as well as reduced liver blood flow and immature liver enzymes. This all points to increased free drug in the plasma and potential toxicity, although the larger volume of distribution in neonates tends to offset these changes. It is thus important to follow guidelines on maximum recommended doses when doing regional blocks. Essentially all RA blocks that are useful in the adult population can be used in the pediatric population, with special attention to the toxic drug doses and the anatomical landmarks. Many obstacles in performing RA in the pediatric population may be related to the availability of the appropriate sizes of needles for the patient, especially the neonate. Close post-block monitoring needs to be available. Especially if narcotics are to be used, the nursing staff needs to be carefully educated regarding the signs of toxicity and side effects of these drugs in the pediatric population. . Table 10.2 gives the maximum recommended doses for commonly used local anaesthetic agents. Commonly performed regional procedures include caudals, epidurals, spinals, ilio-inguinal blocks, and penile blocks. Recently, there has been an increased use of ultrasonography in pediatric regional anaesthesia and, with it, an exponential increase in the number and types of blocks being performed. With ultrasound guidance (USG), it is possible to see anatomical structures in real time and precisely deliver the local anaesthetic to the desired location. This is par 

10

ticularly beneficial to pediatric practitioners because of the close anatomical relationship of vital structures (nerves, vessels, epidural space, spinal cord, bowel, etc.). When compared to blocks done using anatomical landmarks or nerve stimulation techniques, ultrasound-­ guided peripheral nerve blocks had the advantages of shorter block performance time, higher success rate, shorter onset time, longer block duration, and use of smaller amounts of local anaesthetic [18]. The use of ultrasound has also brought more blocks into the scope of practice of pediatric anaesthetists. Rectus sheath and transversus abdominis plane (TAP) blocks are increasingly being used in abdominal surgery. Rectus sheath blocks can provide analgesia for umbilical and epigastric hernia repairs, laparoscopic surgery, and other small midline incisions at the level of the umbilicus. TAP blocks are useful for all surgeries that involve the abdominal wall. These include laparotomy, pyloromyotomy, Nissen fundoplication, open gastric tube insertion, laparoscopic appendectomy, colostomy takedown, bilateral ureteral reimplantation, and bilateral inguinal hernia repair. The TAP block offers a reasonable alternative to neuraxial blocks when these are contraindicated or technically challenging [19]. However, unlike spinal or epidural anaesthesia, these truncal blocks only provide superficial analgesia of the abdominal wall and do not eliminate pain from visceral structures. Thus, not only is general anaesthesia or deep sedation required, the patient will frequently require supplemental parenteral opioid administration. The advantage lies in limiting opioid needs after abdominal procedures. Upper extremity blocks such as interscalene and supraclavicular nerve blocks can be performed safely in the pediatric population and may even limit the need for general anaesthesia with some older patients. 10.9  Postoperative Care

Following the end of the anaesthetic is a period of physiologic stabilization that typically takes place in a post-­anaesthetic care unit (PACU), recovery room, or an intensive care unit (ICU). Emergence and recovery describe the transition from the anaesthetic state ultimately to the patient’s baseline state. During this period, the patient typically awakens from general anaesthesia and regains protective reflexes. The immediate postoperative period is a period of maximal hazard that calls for continuous patient monitoring. The commonest complications are airway obstruction, hypoventilation, and hypoxia. For children who are intubated, the tube should remain in situ until they are fully awake. Laryngospasm is common at extubation, especially in patients who are in the second stage of anaesthesia when they are nei-

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ther deeply anaesthetized nor fully awake. The pharynx should be carefully suctioned before extubation. Oxygen should be administered immediately after extubation and the patient observed for adequate depth of respiration, oxygen saturation, activity, and colour. These children should be cared for by trained staff in the recovery room and should be returned to the ward only after regaining full consciousness and protective reflexes. They should be pain-free and comfortable and have stable vital signs, and there should be no active bleeding from the surgical site. 10.10  Perioperative Anaesthesia

Institution

Section of Anaesthesiology & Intensive Care, Astrid Lindgrens Children’s Hospital/ Karolinska University Hospital- Solna, Stockholm, Sweden

Reference

Pediatric Anesth 2015; (1): 100–106

Problem

Despite the use of long-acting local anaesthetics, the block duration of single-injection techniques is frequently insufficient to cover the major part of the first 24 hours, which is often the most painful part of the postoperative period

Study design

Review article

Results

Different adjuncts such as preservative-free morphine, ketamine, clonidine, and dexmedetomidine are used to prolong and optimize postoperative pain relief in children

Conclusion

The use of preservative-free morphine, ketamine, and clonidine is supported by the literature. The article makes a strong case for the use of adjuncts to prolong local anaesthetic blockade. Preservative-free morphine which is widely used unfortunately has side effects, e.g. PONV, pruritus, and paralytic ileus, and the potential for delayed respiratory depression. The author quotes current research that shows clonidine as currently being the safest and most versatile adjunct in prolonging local anaesthetic blockade

Complications

10

Complications may occur during anaesthesia and in the immediate postoperative period. The commonest complication is airway obstruction from failed or difficult intubation, wrong positioning, mucous plug, blood clot, or subglottic oedema following endotracheal extubation. Laryngospasm and bronchospasm may occur, especially if tracheal intubation is attempted under light planes of anaesthesia. Hypothermia and hypoglycaemia are common in preterm neonates and newborns of diabetic mothers. Bradycardia, when it occurs, is a late sign and should be promptly treated with atropine. Nausea and vomiting, postoperative bleeding, pain, and emergence delirium are other complications that may be seen in the postoperative period. These can be recognized by careful monitoring and should be treated promptly. Most healthy children do well, have an uneventful stay in the PACU, and are quickly reunited with their parents. The need for adequate recovery room nursing care should always be emphasized for the pediatric surgical postoperative patient. The anaesthesia care provider must be readily available in case of a cardiorespiratory event and be able to respond quickly with a resuscitation trolley, which should be in this area of the theatre suite. 10.11  Evidence-Based Research Title

Adjuncts should always be used in pediatric regional anaesthesia

Author(s)

Per-Arne Lonnqvist

Key Summary Points 1. There are many cardiovascular, respiratory, and renal physiological differences between a neonate and an adult surgical patient. 2. The neonate is more prone than an adult to cardiovascular and respiratory complications in the perioperative setting. 3. Fasting guidelines for the pediatric surgical patients need to be strictly followed to avoid complications. 4. A trained pediatric anaesthesia care provider will need specialized anaesthesia training and skills to decrease the high complication rate seen in pediatric surgical cases. 5. Pediatric patients require supplies and equipment appropriately suited for their size and anatomical differences. 6. The use of ultrasound guidance has allowed more opportunities for regional anaesthesia in the pediatric population.

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References 1. Jacobs J, Jackson CT.  Some personal recollections and private correspondence of Dr. Crawford Williamson Long: discoverer of anaesthesia with sulphuric ether: together with documentary proofs of his priority in this wonderful discovery. Publisher not identified; 1919. 2. Mai CL, Coté CJ.  A history of pediatric anesthesia: a tale of pioneers and equipment. Pediatr Anesth. 2012;22(6):511–20. 3. Bosenberg AT. Pediatric anesthesia in developing countries. In: Coté JC, Lerman J, Anderson BJ, editors. A practice of anesthesia for infants and children. 6th ed. Philadelphia: Elsevier; 2019. p. 1161–74. 4. Barbour R, Deka P. Pediatric anaesthesia for low-resource settings. Bja Educ. 2017;17(11):351–6. 5. Coté JC, Lerman J, Anderson BJ, editors. A practice of anesthesia for infants and children. 5th ed. Philadelphia: Elsevier; 2013. p. 357–8. 6. Morgan GE, Mikhail MS, Murray MJ, editors. Clinical anesthesiology. 4th ed. New York: Lange Medical Books/McGraw Hill; 2005. p. 923–4. 7. Manning LR, Popowicz AM, Padovan JC, Chait BT, Manning JM.  Gel filtration of dilute human embryonic hemoglobins reveals basis for their increased oxygen binding. Anal Biochem. 2017;519:38–41. 8. Perucca P, Gilliam FG.  Adverse effects of antiepileptic drugs. Lancet Neurol. 2012;11:792–802. 9. Ettinger KS, Jacob AK, Viozzi CF, Van Ess JM, Fillmore WJ, Arce K.  Does intravenous midazolam dose influence the duration of recovery room stay following outpatient third molar surgery? J Oral Maxillofac Surg. 2015;73(12):2287–93.

10. Salanhre E, Rackow H.  The pulmonary exchange of nitrous oxide and halothune in infants and children. Anesthesiology. 1969;30:388–92. 11. Redhu S, Jalwal GK, Saxena M, Shrivastava OP. A comparative study of induction, maintenance and recovery characteristics of sevoflurane and halothane anaesthesia in pediatric patients (6 months to 6 years). J Anaesthesiol Clin Pharmacol. 2010;26:484. 12. Litman RS, Fiadjoe JE, Stricker PA.  In: Coté CJ, Lerman J, Anderson BJ, editors. The pediatric airway in a practice of anesthesia for infants and children. 5th ed. Philadelphia: Elsevier; 2013. p. 237–41. 13. Litman RS, Weissend EE. Developmental changes of laryngeal dimensions in unparalyzed, sedated children. Anesthesiology 2003;98(1):41–5. 14. Calder A, Hegarty M, Erb T. Predictors of postoperative sore throat in intubated children. Pediatric Anaesthesia 2012;22: 239–43. 15. Litman RS, Maxwell LG. Cuffed versus uncuffed endotracheal tubes in pediatric anesthesia: The debate should finally end. Anesthesiology 2013;118(3):500–1. 16. Fischer B. Benefits, risks, and best practice in regional anesthesia: do we have the evidence that we need? Reg Anesth Pain Med. 2010;35:545–8. 17. Veneziano G, Tobias JD. Chloroprocaine for epidural anesthesia in infants and children. Pediatr Anesth. 2017;27:581–90. 18. Rubin K, Sullivan D, Sadhasivam S. Are peripheral and neuraxial blocks with ultrasound guidance more effective and safe in children? Pediatric Anesthesia 2009;19:92–6. 19. Martin DP, Tobias JD. Transversus abdominis blockade: Ready for use in the pediatric population? Anesthesia, Pain & intensive Care 2012;16(2):115–8.

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Pain Management Helen Sowerbutts, J. Matthew Kynes, Jonathan Durell, and Kokila Lakhoo Contents 11.1

Introduction – 116

11.2

Aetiology/Pathophysiology – 116

11.3

Importance of Pain Control – 116

11.4

The Assessment of Pain – 117

11.4.1 11.4.2 11.4.3 11.4.4 11.4.5 11.4.6 11.4.7 11.4.8 11.4.9 11.4.10 11.4.11

 istory – 117 H Physical – 117 Physiological – 117 Behavioural – 117 Assessment Tools – 117 Management – 118 Non-pharmacological Techniques – 118 Analgesia – 119 Additional Methods of Analgesia – 120 Prevention – 121 Ethical Issues – 121

11.5

Evidence-Based Surgery – 121 References – 122

© Springer Nature Switzerland AG 2020 E.A. Ameh et al. (eds.), Pediatric Surgery, https://doi.org/10.1007/978-3-030-41724-6_11

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11.1  Introduction

Pain sensation Sensory cortex

11

Pain of some degree is almost universal in children in hospital – either as a result of disease itself or as a result of interventions. Unfortunately a number studies have Opioids demonstrated that the management of pain in children Ketamine Thalamus is often inadequate, especially in the African context where resources and skills are limited and overwhelming acute life-saving events override pain management. Accurately assessing pain and treating it accordingly Descending modulation can be challenging in children due to the different ways Ascending input in which pain is expressed in the various age groups. Spinothalamic This is compounded by cultural and individual differtract ences in the perception of pain. Effective pain management in children requires much more than just a sound knowledge of analgesic medications. It requires the healthcare professional to be trained and experienced in Local anesthetics Opioids recognising the degree of pain being experienced by chilDorsal horn dren of different age groups. They must be skilled in using pain assessment tools and be able to appreciate the Local anesthetics role of social, cultural and environmental factors in Peripheral nerve influencing pain perception. Careful consideration must Painful Local anesthetics be given to how pain can be prevented and minimised stimulus Anti-inflammatoy drugs when in hospital, and appropriate prescription of analgesics must be combined with a variety of non-­ pharmacological methods to improve pain perception. ..      Fig. 11.1  Basic pathways involved in the perception of pain with Availability of the appropriate medication is another site of action of common analgesic medications. (Adapted from 7 https://commons.­wikimedia.­org/wiki/File:Brain_limbicsystem.­jpg) limiting factor in African healthcare systems [1].  

11.2  Aetiology/Pathophysiology

Pain can be defined as “an unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage” [2]. This definition highlights an important concept which is especially relevant in children; pain has both neurological and higher cognitive components. As a result, the degree of pain experienced is not necessarily a reflection of the underlying illness. A relatively minor procedure for one child might cause intense distress for another. Likewise, the healthcare worker should not underestimate the potential severity of the underlying illness in a child who exteriorizes their pain to a lesser degree. Factors known to affect a child’s pain perception include anxiety, expectation and previous experience, as well as biological factors such as developmental stage and gender. The role of the family, religion and culture is also becoming increasingly recognised in the west [3]; however in Africa this lags behind due to other life-­ threatening illnesses. The basic pathways thought to underlie the perception of pain are shown in . Fig. 11.1. The pathway was originally described by the Melzack-Wall gate control theory in 1965 [4]. It states that the detection and trans 

mission of pain from the periphery takes place by A-delta and C nerve fibres which travel to the spinal cord where a reflex withdrawal arc is triggered. Pain impulses are simultaneously transmitted up the spinal cord to the thalamus and cortex. Various ascending and descending pathways from the cortex and reticular formation allow levels of arousal and higher cognitive functioning to modify the basic pathway. Inflammatory mediators such as prostaglandins and bradykinins have been found to be responsible for stimulating nerve receptors in the periphery. Neurotransmitters such as endorphins and encephalins are thought to be, at least partly, responsible for the central modulation of the pain response. As a result both the initial inflammatory response and central pathways involved in pain perception are targets for analgesics. 11.3  Importance of Pain Control

A child in pain is distressing for everyone involved in their care. However it is increasingly being recognised that the deleterious effects of pain are more far-reaching than the immediate psychological dimension. The experience of pain leads to activation of the sympathetic nervous system. This has various potentially harmful effects

117 Pain Management

including increased myocardial stress and hypertension. In neonates pain can precipitate apnoeas, and infants may experience syncopal episodes. Pain also leads to activation of the stress axis which causes increased blood cortisol levels which could impair wound healing. In addition patients in pain are less likely to mobilise in the post-operative period putting them at increased risk of atelectasis and chest infections [5]. Increased risk of deep vein thrombosis is also a concern in the adolescent age group. The culmination of these adverse consequences is an increased length of hospital stay and associated increased costs. There are also longer-term consequences to consider with a child who has suffered a distressing experience likely to be more distressed and less co-operative in the future. 11.4  The Assessment of Pain

Assessing how much pain a child is in and reasons the child may be in pain is the first step towards appropriate management. Naturally the source of pain should be identified by using investigations appropriate to the differential diagnosis. However the accurate assessment of pain in children requires separate consideration of the history of the pain, observation and examination of the child and the use of validated scoring tools in addition to knowledge of the underlying cause of discomfort. No one method should be used in isolation. The child and parent should both be consulted, as well as a range of appropriately trained and experienced healthcare professionals. 11.4.1  History

A good history of pain can aid the clinician in diagnosing the underlying condition as well as gain insight into the degree of discomfort. Where possible the clinician should seek the child’s description of the pain. Parental report is also useful. The “SOCRATES” mnemonic is helpful to use whenever taking a pain history – enquiry should be made to the site, onset, character, radiation, associations, time course, exacerbating/relieving factors and the severity of the pain. Questions pertaining to the effect of the pain on the child’s level of activity and behaviour are often especially insightful. In particular the child’s ability to partake in usual activities or their interest in pleasurable activities should be asked. Enquiry should be made into school absences, sleep disturbance and reduced interest in feeding which are often also particularly significant. In taking the history, the clinician should also attempt to elicit family beliefs and expectations about pain and disease. Previous experiences of the child or other family members may well affect how the child and

parents respond to pain. Culture also affects how pain is described or admitted to. 11.4.2  Physical

The signs from the physical examination which can be used to make an assessment of pain largely fall into two categories: behavioural and physiological. 11.4.3  Physiological

Firstly the cause of pain may be identified, for example, seeing a visible wound or palpating abdominal guarding suggestive of peritoneal irritation. Secondly increased heart rate, respiratory rate and blood pressure are indicative of sympathetic stimulation in response to pain. Such signs are objective and do not require the child’s co-operation. They are therefore particularly important in the preverbal child, those with physical or mental disability and impaired consciousness and the apparently “stoical” child. However they are also non-specific indicators of physiological stress and so should not be used in isolation. Traditional healer’s markings are other good indicators of site of pain and disease. 11.4.4  Behavioural

These may be a generalised response to pain such as facial expression, irritability, crying or lethargy or more specific reaction to certain types of pain such as ear pulling, assuming certain postures or refusal to move a certain limb. Although useful, one should not be misled by such signs. There is well-established cultural and even gender-related variation in the degree to which pain is externalised – particularly in the social acceptability of crying. The degree of illness can also influence the extent to which a child is able to express their pain. One should always beware of underestimating the degree of pain being experienced in a critically ill child. In some cultures pain is acknowledged as a sign of weakness, and this taboo needs to be eradicated. 11.4.5  Assessment Tools

Various “pain scales” have been developed to help measure the degree of pain being experienced by a child. Using such tools has been shown to improve pain management and aid nursing care [6]. The choice of scale should reflect the nature of pain (e.g. acute versus chronic pain), the ethnicity of the child and crucially their age and developmental level. Children

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..      Fig. 11.2  Example of a pain scale using facial expressions of pain severity. (Source: Wong-Baker Faces Pain Scale 1981)

Wong-Baker FACES Pain Rating Scale

0 No hurt

11

2 Hurts little bit

over 3 are generally considered to have the cognitive ability to use self-report scales. Commonly employed techniques involve the child being asked to point to a photograph or cartoon of a face in various degrees of pain, or the use of linear analogue scales reflecting the continuum of pain intensity. Examples of commonly used tools and the age group in which they are validated include the Oucher scale, from age 3  years; the Bieri scale, from age 6  years; the Wong-Baker Faces Pain Scale, 8–12  years; and the Adolescent Pediatric Pain Tool validated in children from 8 to 17 years [7]. Tools which use cartoon representation of children’s faces in various degrees of pain are likely to be more globally applicable and maybe especially useful where resources are limited. An example is shown in . Fig. 11.2. In children who are not considered able to verbalise their pain adequately, behavioural scales can be employed. The Face, Legs, Activity, Cry and Consolability (FLACC) scale, the Toddler-Preschooler Post-­operative Pain Scale (TPPPS) and the Children’s Hospital of Eastern Ontario Pain Scale (CHEOPS) are generally thought to be suitable in children from 1 to 5  years. Specific scoring systems encompassing behaviour observation and physiological variables should be used in neonates, with separate tools needed for use in premature babies. Ideally a variety of different pain scales should be available with choice of which scale is used determined on an individual basis. Pain assessment using such tools should be approached with the same attention as that of vital signs: by staff trained in its assessment and who constantly re-evaluate the effectiveness of interventions. Pain flow sheets included in the hospital record may be useful in meeting this goal. Parents should also be educated in the ongoing assessment of their child’s pain.  

11.4.6  Management

It goes without saying that treatment of the underlying condition is critical to managing a child’s pain. However this is often not immediately possible, and crucially many treatments themselves cause pain. Adequate

4 Hurts little more

6 Hurts even more

8 Hurts whole lot

10 Hurts worst

symptomatic relief is therefore essential. In order to control pain effectively, consideration must be given to both pharmacological and non-pharmacological methods of management. The relative use of each should be tailored to individual child, and each intervention should be modified according to assessments of effectiveness. 11.4.7  Non-pharmacological Techniques

Nondrug methods often do not alleviate pain completely but help make it more tolerable by providing the child with coping mechanisms. The hospital environment is often a source of distress in itself and compounds the experience of pain in children. In recognition of this, attempts should be made to keep to the child’s normal routine when in hospital, the number of “new” people tending the child should be minimised, and parents should be involved as much as possible in care. Other nondrug methods can be employed in specific situations – especially in relation to certain procedure-­ related pain. Distraction is especially useful for short procedures [8]. Methods should be age-specific and chosen to reflect the interests of the child. Commonly used examples include videos, games and books for older children and bubbles, lights and music for younger children. Feeding an infant and using a pacifier are simple and inexpensive interventions which have been shown to have analgesic effects [9]. Relaxation techniques such as gentle rocking and massage have also been used with some success. Discussion of the procedure, what it involves and why it is necessary, is often useful in older children. Allowing younger children to familiarise themselves with equipment by first playing with it in a non-­pressurised environment is also useful to reduce the shock associated with procedures. “Play specialists” – specially trained members of staff who are familiar in using a variety of such techniques and able to identify when best to use these  – have been shown to reduce length of stay and increase compliance in some hospitals [10].

119 Pain Management

11.4.8  Analgesia

anti-inflammatory drug (NSAID) in addition. Drugs such as ibuprofen and diclofenac work by inhibiting The prescription of analgesics should follow the WHO prostaglandin synthesis and reducing inflammation pain management ladder (. Fig. 11.3). A key principle through the competitively reversible inhibition of cyclobehind this is the cumulative effect of drugs and the oxygenase-­1 and cyclooxygenase-2 enzymes. This leads stepwise addition of drugs to address pain requirements. to decrease in the formation of prostaglandins and Similarly, as pain requirements reduce (i.e. in the post-­ thromboxane from arachidonic acid. They are therefore operative period), analgesia should be reduced in a step- especially valuable in patients with surgical pain. Oral wise manner down the ladder. The route of and rectal preparations are available, with rectal diclofadministration, dosage and timing should be tailored to enac being particularly well absorbed and of great use in suit the individual child. In particular, it is important to acute pain relief. Caution should be exercised in patients realise that the gastrointestinal absorption of medica- with asthma and renal or hepatic impairment. They tions is affected after major surgery, meaning oral should not be used in patients with known bleeding tenadministration is often inappropriate in this setting. dency or those under 3 months of age. Because of risks Age- and weight-appropriate dosages for each analgesic of gastric irritation, they should ideally be given with should be calculated for each child on an individual food or milk. If analgesic requirements are still not met, then basis. codeine, a mild opiate, should be administered. Paracetamol is an excellent first-line drug for chilAlthough this is generally considered a safe drug dren with pain. It exists in forms suitable for oral, rectal with a significantly lower incidence of respiratory and intravenous administration. Due to the often slow depression than other stronger opioids, nausea absorption from the rectum, this route is less commonly and constipation are relatively common side effects used. It is generally well-tolerated and low in side effects which should be anticipated wherever codeine is preas long as the maximum daily dose is not exceeded. scribed. Codeine phosphate is most commonly given Children who do not get sufficient analgesia from by mouth, although rectal preparations are availparacetamol alone should be prescribed a non-steroidal  

..      Fig. 11.3  The principles of the WHO analgesic ladder (PCA patient-controlled analgesia, NCA nurse-controlled analgesia, NSAID non-steroidal anti-inflammatory drug). (Source: ORH & NOC NHS Trusts, Version 1, July 2003. L Cross RN & Dr. H Bridge)

Analgesic ladder Pharmacological management of acute pain in children (age ≥ 1 year)

Severe pain

Continue to give regular paracetamol ± NSAID

Oromorph

Continue to give regular paracetamol ± NSAID

Codeine

Continue to give regular paracetamol ± NSAID

Paracetamol + diclofenac or Paracetamol + ibuprofen Increasing pain

Moderate pain

Mild pain

Patient controlled morphine Nurse controlled morphine IV morphine rescue Epidural infusion

Diclofenac or Ibuprofen or Paracetamol

11

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able. There is a current ban on the use of codeine in children under the age of 18 years due to incidences of life-threatening adverse reactions in children with obstructive sleep apnoea. Codeine should also be used with caution in the African community as studies have shown that up to 29.0% of the African community are ultrarapid metabolisers of codeine; therefore this leads to a rapid rise in the blood morphine concentration and increases the likelihood of an adverse reaction. In patients whose pain is still not adequately controlled, or those who are deemed to have severe pain at initial assessment, a strong opioid should be used. The “lower steps” of the analgesic ladder should always be prescribed in addition, with the exception of codeine. Morphine may be administered orally, intramuscularly, rectally or intravenously depending on clinical need. An intranasal preparation of diamorphine is also now available and is especially useful in the emergency management of acute pain where intravenous access is not always available [11]. Patient-controlled analgesia (or PCA) is a mode of intravenous morphine administration which is an alternative mode of administration by which the patient can choose when morphine doses are given according to need. PCA has been found to produce the same analgesic effect as IM regimens but with less sedation [12]. Morphine has multiple side effects which should be anticipated whenever it is prescribed. Nausea and vomiting are commonplace, meaning anti-emetics should be routinely prescribed on an “as required” basis. Urinary retention is a recognised complication, especially in post-operative patients, meaning many centres routinely place urinary catheters in patients until their opiate requirement has ceased. Respiratory depression is the most feared complication associated with the use of morphine. Regular, documented monitoring of sedation level and respiratory parameters is mandatory, as should the co-prescription of “as required” naloxone wherever opioids are prescribed. Concern about respiratory compromise should not however influence the decision to use morphine in those who need it. Parents and healthcare professionals alike should be reassured that dependence in children with surgical pain is rare. Opioid use in Africa is rare, in part due to strict national laws, opioid addiction, misuse of drugs, lack of knowledge and non-availability as reported by the World Health Organization [13]. For example, morphine consumption in South Africa for 2004 was 4.6682 mg/capita in comparison with Uganda’s 0.4001  mg/capita, Tanzania’s 0.3250  mg/capita and Zambia’s 0.0704  mg/

capita, and the use of pethidine in Uganda for 2004 was 0.2272 mg/capita, whereas in contrast South Africa consumed 3.7694 mg/capita [14]. 11.4.9  Additional Methods of Analgesia

Certain additional techniques are frequently employed in the perioperative period to improve pain management. Local anaesthetics can be used to create specific nerve blocks to reduce post-operative pain sensation from specific sites. The duration of such blocks depends upon the specific anaesthetic used but is typically around 6–8 hours. Local anaesthetics also now exist in a variety of formats including gels and creams that can be applied post-operatively, as well as solutions which can be infiltrated into operative sites. Local application of anaesthetic creams is particularly useful in procedures involving the skin or mucus membranes and has been shown to be effective in reducing wound pain in the post-operative period [15]. An advantage of this is that community medical officers can easily acquire and utilise this technique to reduce pain associated with procedures. When a greater area of analgesic coverage is required, an epidural may be used. This is a form of regional anaesthesia involving injection of analgesics (usually local anaesthetic with or without opioids) through a catheter placed into the epidural space. They are especially useful in thoracic procedures and after laparotomy [16]. Epidurals are usually inserted in the anaesthetic room and can be linked to a PCA system (where they become PCEA systems). Their main advantage is that the analgesic action of opioids can be gained without the systemic side effects. However, there are numerous disadvantages to the system. The incidence of post-­ operative urinary retention is reasonably high, so catheterisation is often recommended, epidurals should be avoided in patients at high risk of bleeding or infection, and there is a risk of inappropriate level of blockade, so sensory level should be routinely checked whilst an epidural is in place. Ketamine merits special mention with regard to pain control in areas where access to, and training in administering other modes of, analgesia is limited. Ketamine is a synthetic drug that has a mechanism of action through NMDA (N-methyl D-aspartate) receptor antagonist but also works at opioid receptors and monoamine transporters. This anaesthetic drug has also been shown to have good analgesic properties at sub-anaesthetic dosages [17]. It can be administered intravenously or by intramuscular injection and is generally well-tolerated in pediatric patients. The side-effect profile is diverse and

121 Pain Management

includes hypertension, cardiac dysrhythmias, increased 11.5  Evidence-Based Surgery skeletal muscle tone, increased intraocular pressure, airway obstruction, laryngospasm, increased bronchial Evidence-based surgery secretions and emergence reactions. Diazepam is co-­ prescribed to buffer the duration and intensity of side Title A comparison between EMLA cream applieffects. cation and lidocaine infiltration for post-­ operative analgesia after inguinal herniotomy in children

11.4.10  Prevention

Although in practice it is difficult to completely prevent pain in hospitalised children, several strategies can help minimise it. Naturally the accurate diagnosis and prompt treatment of the underlying condition before pain escalates is highly desirable. Regular prescription of analgesia is more effective than medicine given only when pain arises. The clinician should also attempt to recognise the potential for procedures to be painful or distressing and carefully consider which measures are really necessary so that only those which are likely to bring about a change in management are undertaken. Where potentially painful procedures are required, a range of methods can be employed to prevent unnecessary pain. This includes administration of analgesics before an event, as well as the use of special additional measures such as “Entonox” in dressing changes of burns patients, or local anaesthetic creams (“EMLA” or “Amitop”) and cold sprays to minimise discomfort associated with phlebotomy or removal of foreign objects. In the longer term, minimising pain for pediatric patients will require continued efforts to educate and train staff in its assessment and management. Crucially this should involve dispelling commonly held myths such as infants do not feel pain, the active child is not in pain, and the general feeling that children have to “earn” analgesics before they are given.

Authors

Usmani H, Pal Singh S, Quadir A, Chana RS

Institution

Department of Anesthesia, Jawaharlal Nehru Medical College, Aligarh Muslim University, Aligarh, India

Reference

Reg Anesth Pain Med. 2009 Mar–Apr; 34(2):106–9

Problem

Post-operative pain relief following inguinal herniotomy

Intervention

Topical application of 5% EMLA cream before surgery or wound infiltration with 1% lidocaine

Comparison/control (quality of evidence)

Study group: 90 children aged 4–12 undergoing elective herniotomy under general anaesthetic. Patients were randomly assigned to placebo cream alone, 5% EMLA cream, or placebo cream +1% lidocaine infiltration after induction of anaesthesia. Operative protocol was standardised between groups. The requirement for post-operative analgesia was compared between groups

Outcome/ effect

The number of patients requiring fentanyl as rescue analgesia was significantly less in the study groups than in the placebo group. Topical application of EMLA provided post-operative pain relief comparable to infiltration with 1% lidocaine

Historical significance/ comments

Suggests that the application of local anaesthetic cream is a viable alternative to wound infiltration in the control of post-operative pain. This would be a valuable strategy in settings where clinical training and resources are limited

11.4.11  Ethical Issues

The African child is particularly vulnerable to disease and injury and, subsequently, to pain and suffering. Factors such as inadequate training, language barriers, cultural diversity, limited resources and the burden of disease prevent sick and injured children from receiving basic pain care. This situation can only be rectified by providing pre- and post-graduate training on the safe use of analgesic preparations, drugs and government support. These ethical issues are best summarised in a review titled Challenges associated with pediatric pain management in Sub Saharan Africa in the International Journal of Surgery [1].

Evidence-based surgery Title

Good practice in post-operative and procedural pain management

Authors

Association of Pediatric Anaesthetists of Great Britain and Ireland

Institution

Association of Pediatric Anaesthetists of Great Britain and Ireland

Reference

Guideline

Problem

Review of pain management strategies in various clinical scenarios

Intervention

Review of analgesic strategies

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Evidence-based surgery Comparison/ control (quality of evidence)

Each analgesic scenario has recommended use of analgesia strategy and grading of the evidence for this recommendation

Outcome/effect

Great paper for basic and advanced methods of analgesia

Historical significance/comments

Allows for various options in treating pain in children

Key Summary Points

11

55 Pain, of some degree, is almost universal in hospitalised children as a result either of underlying disease or interventions. 55 The recognition and subsequent management of pain is often inadequate in children. 55 Healthcare professionals have a moral obligation to provide the best possible management of children’s pain and should be trained in pain recognition. 55 The perception and expression of pain is highly dependent on the age and cognitive function of the child. 55 Accurate determination of the level of pain is the first step to adequate management and should take into consideration the patient and child’s report, the change in behaviour of the child, the measurement of physiological parameters and knowledge of the underlying medical condition. 55 Culturally and age-validated scoring tools should be routinely used in the assessment of pain in children. 55 A combination of pharmacological and nondrug methods should be used for managing pain. 55 Clinicians should anticipate pain in children and minimise the number of potentially painful procedures a child is subjected to.

References 1. Albertyn R, Rode H, Millar AJ, Thomas J.  Challenges associated with paediatric pain management in Sub Saharan Africa. Int J Surg. 2009;7(2):91–3. 2. Merskey H, Bogduk N.  Classification of chronic pain. Seattle: International Association for the Study of Pain Press; 1994. p. 210. 3. Twycross A, Moriarty A, Betts T. Pediatric pain management: a multi-disciplinary approach. Oxford: Radcliffe Medical Press; 1999. p. 56–76. 4. Melzack R, Wall PD. Pain mechanisms: a new theory. Science. 1965;150:971–9. 5. Eland JM.  Pain in children. Nurs Clin North Am. 1990;25(4): 871–84. 6. Schofield P. Using assessment tools to help patients in pain. Prof Nurse. 1995;10(11):703–6. 7. Cohen LL, et al. Evidence based assessment of pain. J Pediatr Psychol. 2008;33(9):939–55; discussion 956-7. Epub 2007 Nov 17. Review. 8. Carter B. Child and infant pain: principles of nursing care and management. London: Chapman and Hall; 1994. 9. Sexton S, Natale R.  Risks and benefits of pacifiers. Am Fam Physician. 2009;79(8):681–5. 10. Dix A.  Clinical management. Where medicine meets management. Let us play. Health Serv J. 2004;114(5902):26–7. 11. Borland M, Jacobs I, King B, O’Brien D. A randomised crossover trial of patient controlled intranasal fentanyl and oral morphine for procedural wound care in adult patients with burns. Burns. 2004;30(3):262–8. 12. Berde DB, et  al. Patient controlled analgesia in children and adolescents: a randomised prospective comparison with intramuscular morphine for post-operative analgesia. Pediatrics. 1993;118:460–6. 13. Adams V, Bertolino M, et  al. Access to pain relief  – a basic human right. Report for the hospice and palliative care day. 2007. Available from: http://www.­worldday.­org/documents/access_to_relief.­pdf. 14. Availability of morphine and pethidine in the world and Africa. Advocacy for palliative care in Africa: a focus on essential pain medication accessibility. 2006. Available from: http://www.­ medsch.­wisc.­edu/painpolicy. 15. Usmani H, Pal Singh S, Quadir A, Chana RS.  A comparison between EMLA cream application versus lidocaine infiltration for post-operative analgesia after inguinal Herniotomy in children. Reg Anesth Pain Med. 2009;34(2):106–9. 16. Block BM, Liu SS, Rowlingson AJ, Cowan AR, Cowan JA, Wu CL.  Efficacy of postoperative epidural analgesia: a meta-­ analysis. JAMA. 2003;290(18):2455–63. 17. Mistry RB, Nahata MC. Ketamine for conscious sedation in pediatric emergency care. Pharmacotherapy. 2005;25(8):1104–11.

123

Intensive Care Immaculate W. K. Barasa and Erik N. Hansen Contents 12.1

Introduction – 124

12.2

Approach to the Critically Ill Child – 124

12.2.1 12.2.2 12.2.3

 irway – 125 A Breathing – 125 Circulation – 129

12.3

Specific Domains of Dysfunction – 129

12.3.1 12.3.2 12.3.3

 eurologic – 129 N Infection – 130 Renal – 131

12.4

 elected Topics of Management of the S Critically Ill Child – 131

12.4.1 12.4.2 12.4.3 12.4.4

 nalgesia and Sedation – 131 A Device-Associated Infections (DAIs) – 132 Venous Thromboembolism (VTE) Prophylaxis in Children – 132 Malnutrition – 132

12.5

 hallenges in Critical Care in Resource-Limited C Contexts – 133

12.6

Evidence-Based Research (. Table 12.7) – 134  

References – 134

© Springer Nature Switzerland AG 2020 E.A. Ameh et al. (eds.), Pediatric Surgery, https://doi.org/10.1007/978-3-030-41724-6_12

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12.1  Introduction

12

Injury or illness is defined as critical when one or more organ systems are either in danger of failing or have begun to fail. In this situation, the possibility of incomplete recovery or death exists. Critical care comprises the monitoring, support, treatment, and interventions for the organ systems in failure. Pediatric critical care not only encompasses bedside management of children’s severe, potentially life-threatening medical or surgical illness but also extends to providing support to the child’s family or caregivers. The challenge lies in the complex balance of providing support of single or multiple organ systems in failure while at the same time minimizing adverse consequences of treatment. In the high-resourced setting, this level of care is typically provided in a dedicated pediatric intensive care environment with the capacity to offer sophisticated monitoring, diagnostic and therapeutic interventions, and advanced technological support for the critically ill child. When the outcome is poor or death ensues, critical care focus shifts to palliative and, if necessary, bereavement support. The spectrum of disease in children differs from that of the adult population, as does the pediatric response to illness, surgery, or injury. Congenital abnormalities, genetic syndromes, inborn errors of metabolism, and toxins, as well as trauma, including birth-related and non-accidental injury, all influence the differential diagnosis of an acutely unwell child. Regardless of the etiology, basic principles of initial management and stabilization should be applied in all situations [1, 2]. Critical care provision in the developing world faces multiple challenges inherent to a resource-limited setting. Nonetheless, it is possible to provide context-appropriate measures that greatly enhance the provision of healthcare and reduce morbidity and mortality. Riviello et al. [3] summarizes the challenges and principles for developing critical care in a resource-poor setting based on the experience of AIC Kijabe Hospital in starting and running a five-bed intensive care unit open to patients of all ages. The four core areas are (1) personnel and training, (2) equipment and support services, (3) ethics, and (4) research.

..      Table 12.1  AIC Kijabe Hospital ICU statistics for October 2013–October 2015 Total ICU admissions

666

Total pediatric ICU admissions

247

% Pediatric patients ventilated

50%

Pediatric ICU LOS (median)

3d

Pediatric ICU mortality (2013)

34.8%

An overview of ICU statistics at AIC Kijabe Hospital in Kijabe, Kenya, between October 2013 and October 2015 is found in . Tables 12.1 and 12.2.  

12.2  Approach to the Critically Ill Child

A systematic approach to the assessment and management of a critically ill patient is essential. Principles of the approach are outlined below. ..      Table 12.2  Summary of pediatric surgical cases requiring ICU admission at AIC Kijabe Hospital from October 2013–October 2015 in children older than 2 months Diagnosis/procedure

Number

Craniotomy for brain tumors

37

VPS malfunction

12

VPS infections

9

Aspiration pneumonia in HC/MMC

5

Post-op adenoidectomy/tonsillectomy

8

Encephalocele

8

Facial soft tissue defects (congenital and tumors)

8

Spinal cord SOL

8

Complicated cleft palate

5

Burns

3

TBI

3

Laryngeal abnormalities (webs, cysts, malacia)

4

Peritonitis

5

Necrotizing soft tissue infections

3

Biliary atresia

5

PDA ligation

2

Brain abscess

7

Chest tubes for effusion, empyema

5

Upper GI bleed

2

Wilms tumor

2

Septic arthritis

2

Esophageal perforations

2

Othersa

6

Source: combined pediatric audits and AIC Kijabe Hospital database VPS ventriculoperitoneal shunt, HC hydrocephalus, MMC myelomeningocele, SOL space-occupying lesion, TBI traumatic brain injury, PDA patent ductus arteriosus aPulmonary hydatid cyst, mediastinal lymphoma, compartment syndrome, malignant hyperthermia, neuroblastoma, pyloric stenosis

125 Intensive Care

12.2.1  Airway

A rapid yet thorough assessment of airway patency and the patient’s ability to protect the airway is essential. Specifically, this involves: 55 Assessing chest rise 55 Listening for abnormal airway noises (e.g., stridor) 55 Listening for breathing (airway movement) Airway compromise is classified as functional or structural. Functional causes include altered muscle tone and function due to depressed mental status, drug effects, hypoxia, and/or brain injury. Structural causes include airway edema as a result of airway manipulation (e.g., intubation, oral surgery), foreign body aspiration, fluid (blood and/or secretions), and extrinsic compression of the airway. 12.2.1.1  Airway Management

Positioning is the first key maneuver for ensuring a patent airway. Newborns should be in the neutral position, while older children should be placed in the sniffing position (. Fig. 12.1). One should ensure cervical spine stabilization in the case of known or suspected injury. In such cases, a jaw thrust can be helpful. Inspect the oropharynx, removing any foreign bodies, preferably with Magill forceps. Suction any blood or secretions from the upper airway. Because the pediatric airway is narrow, small changes in diameter from secretions, blood, etc. may cause significant limitations in airflow. Certain adjunct devices are also important to have and use as needed. An oropharyngeal airway or nasal trumpet can help relieve posterior pharyngeal obstructions due to retrotrusion of the tongue or other soft tissues. While not a truly “protected” airway, the laryngeal mask airway (LMA) can be lifesaving in the setting of a difficult intubation. Ultimately, endotracheal intubation or surgical tracheostomy may be necessary to secure the airway [4]. Epinephrine nebulization and/or intravenous dexamethasone is frequently used to prevent and/or treat post-extubation stridor even though no solid evidence exists as to their benefit [5–7]. Constriction of the lower airways as seen in reactive airway disease, pulmonary edema, or anaphylaxis may also impair air movement. A trial of a bronchodilator (salbutamol nebulization and/or intravenous magnesium sulfate) to relax the airway musculature is sometimes required.  

12.2.2  Breathing

Respiratory failure is a common cause of morbidity and mortality in the pediatric population. Majority of pediatric cardiac arrests occur secondary to hypoxia due to respiratory failure [9].

..      Fig. 12.1  Neutral head position in a young infant [8]

The goal of assessing the presence, sufficiency, and pattern of breathing in critically ill children is to identify impending respiratory failure and to prevent its occurrence. The clinical and laboratory parameters to assess include the following: 55 Altered respiratory rate: apnea, hyperpnoea, or hypopnea. 55 Central cyanosis. 55 Increased work of breathing: deep acidotic (Kussmaul) breathing, chest wall retractions, head bobbing, sternal retractions, and nasal flaring. 55 Pattern of chest movement: paradoxical movements as in flail chest, Cheyne-Stokes pattern as in brain injury, etc. 55 Tachycardia. 55 Hypoxia: restlessness, irritability, or lethargy may be manifestations of CNS hypoxemia. Continuous pulse oximetry is crucial. 55 Arterial blood gas measurement: this allows for objective measurement of pH, pO2, pCO2, and HCO3−, thereby providing information on a primary acid-base disorder as well as monitoring of interventions meant to improve oxygenation and ventilation. 12.2.2.1  Blood Gas Monitoring

The use of blood gases (arterial, venous, and/or capillary) to monitor critically ill neonates, infants, and children is standard practice in high-resourced intensive care units. The use, however, in LMIC settings is more challenging because of the costs associated with purchasing and maintenance of a blood gas analyzer as well as procurement of necessary consumable supplies. For example, at AIC Kijabe Hospital in Kijabe, Kenya, critically ill patients were cared for and ventilated without the routine use of blood gas analyses until 2015. This is

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..      Table 12.3  Primary acid-base abnormalities Normal

↓

↑

pH

7.35–7.45

Acidemia

Alkemia

pCO2

35–45 mmHg

Respiratory alkalosis

Respiratory acidosis

Bicarbonate

22–26 mmol/L

Metabolic acidosis

Metabolic alkalosis

likely true in many equivalent ICUs in sub-Saharan Africa. Nevertheless, it behooves the clinician to be able to understand and interpret blood gas analyses. A detailed analysis of blood gases is beyond the scope of this chapter, but Haber provides an excellent, pragmatic approach to the interpretation of an arterial blood gas [10]. A summary of findings in primary acid-base disorders is found in . Table 12.3.  

12.2.2.2  Interventions for Respiratory

Support

12

Principally speaking, patients must be able to oxygenate (take up oxygen) and ventilate (adequately exchange CO2) at the alveolar level. Any intervention must address the primary underlying problem. At the most basic level, interventions to improve oxygenation are (1) increasing the FiO2 and (2) increasing positive end expiratory pressure (PEEP). Oxygen can be delivered at different flow rates (which, depending on the device correlate to FiO2) based on the oxygen needs of a spontaneously breathing patient with adequate respiratory effort. Typically, low flow rates are administered using simple nasal cannulae or nasopharyngeal catheters. Face masks, in general, deliver higher FiO2. The minimum flow rate through any face mask is 4 L/minute as this prevents CO2 accumulation and rebreathing. Likewise, basic interventions for increasing CO2 exchange alter the minute ventilation.  Volume (VT) × Since minute ventilation (V) = Tidal Respiratory Rate (ƒ), these interventions are focused on increasing VT and/or ƒ. In the setting of impending or acute respiratory failure, more invasive mechanisms are needed, and each of these involves positive pressure ventilation. A brief overview of selected means of respiratory support mechanisms follows:

times better achieved by two healthcare providers. It is often necessary to move the child’s head and neck gently to determine the optimum position to provide effective ventilation. Excessive flexion or extension of the head and neck should be avoided, however, as this often results in airway obstruction. For all children with a known or potential cervical spine injury, the spine should be adequately immobilized, and unnecessary manipulation should be avoided. The two bags commonly used in bag-mask ventilation include the self-inflating bag and the standard anesthetic circuit. The self-inflating bag consists of a bag, oxygen inlet, connector for the face mask of tracheal tube, pressure relief valve, and a reservoir. This bag is relatively easy to use and more available. When used with the reservoir, it can deliver near 100% FiO2. It is useful for emergency ventilation even without an oxygen source since the gas movement generated by bag compression/inflation will inflate the chest with room air. Because the valve mechanism opens only in response to manual bag inflation, the selfinflating bag is not appropriate to deliver oxygen or continuous positive pressure in the spontaneously breathing child. The bag in a standard anesthetic circuit, however, requires a constant supply of fresh gas in order to fill and therefore must be connected to a supply source for use. The advantage of the standard bag over the self-inflating bag is the ability to deliver fresh gas and continuous positive pressure to the spontaneously breathing child and to control the pressures administered with each breath. The system can be difficult to use, however, in all but experienced anesthetists’ hands. Continuous Positive Airway Pressure (CPAP) CPAP delivers a continuous pressure to spontaneously breathing children, thereby aiding the inspiratory effort and generating PEEP which serves to keep the alveoli open at end expiration, recruit collapsed alveoli, and improve V/Q mismatch, thereby improving oxygenation and reducing the work of breathing. CPAP can be delivered via dedicated machines via (1) masks and specialized nasal prongs, (2) bubbleflow nasal CPAP via Hudson prongs, or (3) mechanical ventilators via endotracheal tubes.

High-Flow Nasal Cannula High-flow nasal cannula is a mode of oxygen delivery that is gaining popularity in pediatric intensive care units in high-resourced settings due to its relative ease of use and its minimal interference with the patient because Non-invasive Support of its small profile. HFNC delivers humidified, high-­ Bag Valve Mask flow, heated oxygen via nasal prongs to the patient. It is Effective bag-mask ventilation requires a good seal thought to prevent pharyngeal collapse and obstructive between the mask and face to provide adequate inflation apnea that may be pronounced in some disease entities. pressures as well as the ability to compress the gas-­ HFNC also provides better oxygen delivery and may containing bag in a coordinated manner, which is some- help wash out the physiological dead space.

127 Intensive Care

Invasive Mechanical Ventilation Indications for invasive mechanical ventilation 55 Acute or impending respiratory failure due to upper airway, lower airway, or parenchymal lung disease 55 Inability to protect the airway (depressed level of consciousness from drugs, traumatic brain injury, or space-occupying intracranial lesions) 55 Neuromuscular weakness (e.g., botulism, Guillain-­ Barré syndrome, tetanus, myasthenia gravis, postoperative neuromuscular blockade, etc.) 55 Rarely cardiovascular insufficiency to minimize the work of breathing and thereby decrease oxygen consumption

above PEEP, the inspiratory time, volume loss from a leak around an uncuffed ETT, and the patient’s pulmonary resistance and compliance. The delta P is adjusted to deliver the desired exhaled VT (generally 6–8 mL/kg).

Volume Control The clinician sets a specific tidal volume and inspiratory time. Target tidal volumes in children are 6–8 ml/ kg. Higher tidal volumes may result in repetitive over distension and endothelial damage known as volutrauma. The peek inspiratory pressure (PIP) should be monitored as changes in the PIP may reflect a change in lung compliance or airway resistance. High peak inspiratory pressures require investigations to check for displacement of the endotracheal tube, obstruction of the Factors to address with conventional ventilators airway (blocked ETT by mucus plugs or blood), kink55 Cycling mechanism (pressure- or volume-­controlled) ing of the circuit, worsening lung parenchymal disease, which will drive the desired tidal volume and is often bronchospasm, pneumothorax, and/or abdominal dislinked to a given mode of ventilation tension. 55 Mode of ventilation (e.g., assist control, synchronized Volume-limited ventilation is best used in patients with intermittent mandatory ventilation, or pressure-­ normal resistance and compliance. With poor compliance regulated volume control) or high resistance, the higher PIP may lead to barotrauma 55 Inspiratory/expiratory time (I:E) and increased mortality in patients with ARDS and other 55 Ventilatory rate (breaths/minute) types of pulmonary parenchymal disease. The advantage 55 FiO2 of volume-limited ventilation is that a constant VT is deliv55 PEEP ered even with a changing resistance and compliance. With volume-limited ventilation, manipulation of Cycling the inspiratory time can be used to decrease the PIP. If Standard ventilator modes are either pressure- or the peak airway pressure is unacceptably high, the volume-­controlled. Volume-controlled modes deliver a pressure-­limited mode may be chosen (see below for furpreset tidal volume with each programmed breath, ther discussion of setting the inspiratory time). using whatever inspiratory pressure is necessary to achieve the set volume. Pressure-controlled modes will Modes of Ventilation deliver a preset pressure with each breath. The compli- Three commonly used modes are described below. There ance of the patient’s respiratory system will then deter- is very limited data to demonstrate superiority of one mine how much tidal volume is actually generated. mode over another. Pressure-­controlled modes are typically used in children, and especially neonates, in an effort to minimize Synchronized Intermittent Mandatory Ventilation barotrauma. (SIMV) This is the mode commonly used in pediatric patients in Pressure Control the intensive care unit. With pressure-controlled ventilation, a preset pressure SIMV delivers a set minimum number of breaths above PEEP (sometimes referred to as the delta or ∆P) every minute that are synchronized with the patient’s is delivered over a selected inspiratory time. The inspira- respiratory effort. Full ventilatory support (pressure or tory flow rate depends on the airway pressure and respi- volume) is delivered for the preset number of breaths ratory system compliance, achieving high levels initially each minute. Any breaths initiated by the patient above and decelerating toward zero near the end of inspira- the set rate are not supported. Frequently, SIMV with tion. The delivered tidal volume varies from breath to pressure support is used to augment the spontaneous breath depending on the respiratory system mechanics. breaths initiated by the patient over and above the set However, given that the peak inspiratory pressure (PIP) minimum rate. is controlled, the risk of barotrauma is lessened with respect to volume-controlled ventilation. Assist Control (AC) During pressure-limited ventilation, the delivered VT Classically, this mode delivers a preset V with each T is determined by several factors  – the pressure level breath regardless whether the patient or the ventilator

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initiates the breath. This has typically been a volume-­ controlled mode but can similarly be used in a pressure-­ cycled mechanism. If the patient is tachypneic  – e.g., sepsis, agitation, pain, or CNS disorders – this mode can result in significant respiratory alkalosis given the increased minute ventilation. Pressure-Regulated Volume Control (PRVC) This is a newer and potentially safer mode of ventilation that can be generated by newer-generation ventilators and is fundamentally a volume-controlled mode. A defined tidal volume is delivered with each breath, but the inspiratory pressure is minimized by varying the flow during each breath based on the dynamic compliance of the airway. The ventilator is continuously adapting the inspiratory pressure to changes in the resistance and compliance of the patient’s respiratory system to deliver the selected tidal volume. Since it works within the confines of a preset pressure limit, PRVC may limit the incidence of barotrauma that can occur with standard volume-­ controlled modes.

12

Inspiratory Time and Ventilatory Rate Because time is fixed, adjustments in inspiratory time, and in particular the ratio of inspiratory to expiratory time (I:E), necessarily affect the ventilatory rate. The initial respiratory rate for a mechanically ventilated patient is set near the normal respiratory rate for that age group (. Table 12.6). Other factors to consider include the PaCO2 when available and the desired minute ventilation for patients on pressure-cycled ventilation. The I:E in a normal, spontaneously breathing infant is 1:3–1:4 per breathing cycle. In a sick, ventilated patient, this may shorten to 1:2 and the ventilator adjusted accordingly. Changing the inspiratory time has different effects depending on the cycling mode. With pressure-limited ventilation, the delivery of the tidal breath is pressure-limited and time-cycled (the preset pressure is held until the inspiratory time is completed). Extending the inspiration time will increase the tidal volume. More importantly, the inspiratory time along with the positive end expiratory pressure (PEEP) and PIP determines the mean airway pressure. Extending the inspiratory time increases the mean airway pressure and will thereby typically increase oxygenation. With volume-limited ventilation, extending the inspiratory time serves to decrease the inspiratory flow rate, thereby reducing the PIP. It can also be used as a therapeutic maneuver to help recruit alveoli with long time constants and to help the resolution of atelectasis. Patients with bronchospasm and air trapping generally benefit from a shorter inspiratory time to allow for  

as much exhalation time as possible. Patients with alveolar space disease and poor compliance generally do better with longer inspiratory times to increase mean airway pressure and improve oxygenation. The inspiratory time can be increased up to 1.2–1.5  seconds as needed to increase the mean airway pressure and recruit alveoli, but in practice, the I:E ratio is restricted to 1:1. Reversal of the I:E ratio has been used in the management of patients with severe acute respiratory distress syndrome (ARDS) in an attempt to augment oxygenation and allow weaning of the FiO2 but will often result in breath-­ stacking and increasing pulmonary pressures. FiO2 Immediately after intubation, patients will usually be on 100% FiO2. This should be weaned as soon as possible to allow oxygen saturation above 90% and an acceptable PaCO2. If weaning is not possible, other maneuvers that can be tried include increasing the mean airway pressure by increasing the PEEP, prolonging the inspiratory time, or increasing the hemoglobin if it is low. Positive End Expiratory Pressure (PEEP) and Peak Inspiratory Pressure (PIP) PEEP This is the pressure in the alveoli at the end of expiration which keeps the alveoli patent and prevents repeated opening and closing of the alveoli. PEEP prevents alveolar collapse, thereby maintaining lung volumes and improving V/Q mismatch. PEEP is usually initially set at 4–5 cm H2O for children and may be increased in select circumstances up to 8–10 cm H2O, in consultation with a critical care specialist. An increase in the PEEP increases the MAP and improves oxygenation. Of note, higher levels of PEEP may impair venous return and therefore reduce the cardiac output. In pressure-­controlled modes and depending on pulmonary compliance, an increase in PEEP without a concomitant increase in PIP effects a reduction in tidal volume and therefore minute ventilation for a given respiratory rate. PIP This is the maximum pressure exerted in the major airways during inspiration. PIP = PEEP + DP A useful clinical indicator of adequate PIP is a gentle chest rise with every breath, which should be little more than the chest expansion with spontaneous breathing. The minimum effective PIP should always be used. It ranges from 15 to 20 cm H2O in normal healthy pediatric lungs, but higher PIP may be used.

12

129 Intensive Care

12.2.3  Circulation

..      Table 12.4  Classification of shock

Early recognition of circulatory compromise and appropriate intervention to correct and reduce further progression to circulatory collapse or death are crucial. Cardiac arrests in children most commonly occur secondary to hypoxemia and respiratory arrest as opposed to primary cardiac causes. Shock (. Table 12.4) is a state where the tissue metabolic demands are not met due to inadequate blood flow and suboptimal oxygen delivery. The most common type of shock in children is hypovolemic due to fluid losses through the gastrointestinal tract (e.g., diarrheal illnesses), skin (e.g., burns), inadequate intake (e.g., newborn in the context of poor maternal milk supply), and hemorrhage. Distributive, cardiogenic, and obstructive shock occur less frequently. Shock progresses over a continuum of severity from a compensated to a decompensated state that results in hypotension – a late sign of shock in the pediatric population. In decompensated shock, signs of inadequate end-organ perfusion  – metabolic acidosis, depressed mental status, and poor urinary output – are present. Typical signs of compensated shock include tachycardia, cold extremities with temperature gradient, prolonged capillary refill time, weak peripheral pulses compared with central pulses, and normal systolic BPs. Hypotension parameters by age are shown in . Table 12.5. Management of shock: Early (within 6  hours) goal-directed therapy targeting physiological indicators of end-organ perfusion is recommended on the basis of observational evidence [11]. Large-bore intravenous or intraosseous access, oxygen administration, random blood glucose measurement, correction of obstructive causes of shock (e.g., pneumothorax), and treatment of arrhythmias should be addressed immediately. Fluid administration: For all types of shock, except cardiogenic and in severely malnourished children, 20 cc/kg of isotonic crystalloid should be bolused over 5–10  minutes. After the second bolus, consideration should be given to the need for blood products, especially in trauma or hemorrhagic shock. The heart rate, blood pressure, and pulse oximetry should be continuously monitored during the fluid correction. If a patient in cardiogenic shock is also hypovolemic, 5–10  cc/kg boluses over 10–20  minutes may be given cautiously. See section on malnutrition for rehydration of malnourished patients. Intravenous crystalloid and albumin boluses may be harmful for nonsurgical patients with severe febrile illness who do not have diarrhea and present with signs of impaired perfusion in resource-limited settings [12].  

Shock classification

Etiology

Hypovolemic

Hemorrhage Diarrhea and vomiting Burns Peritonitis

Distributive

Sepsis Anaphylaxis Vasodilating drugs Spinal cord injuries

Cardiogenic

Arrhythmias Cardiomyopathy Myocardial infarction/contusion Congenital structural heart disease Cardiac tamponade

Obstructive

Tension hemo−/pneumothorax Flail chest Pulmonary embolism

Dissociative

Anemia Carbon monoxide poisoning Methemoglobinemia

..      Table 12.5  Hypotension criteria by age [9] Age

SBP

0–28 days

5 minutes but significantly reduced the duration of the longest reflux episode of pH 2  cm), such as some toys, are also likely to remain stuck in the stomach. Ingestion of more than one magnet has been reported to cause necrosis of the intestine trapped between the two magnets [22] (see . Fig.  52.1); therefore, it may be advisable to retrieve the magnets while they are still accessible in the oesophagus or stomach. Multiple magnets should not be observed as other asymptomatic ingested foreign bodies. Serial radiographs at 4–6 h  

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52 ..      Fig. 52.1  Multiple magnets causing necrosis through the proximal and distal bowel loops as well as causing a mesenteric defect due to the necrosis of entrapped mesentery between the two loops of bowel

intervals must confirm progress through gastrointestinal tract. If magnets are static on serial radiographs, then definitive management should be accomplished within 24 h of admission [23]. When the ingested foreign bodies are not retrieved, patients and parents are advised to look for foreign bodies in the stool. If not egested in a week to 10  days, repeat check x-rays are taken, and if no further distal movement of the foreign body is demonstrated beyond the stomach (see . Fig. 52.2), it is best retrieved endoscopically. Laparoscopic, or laparotomy-assisted, retrieval may be indicated very rarely, except for the situation of a secondary complication of obstruction or perforation. One reason to attempt a proactive laparoscopic or laparotomy retrieval is the risk of a secondary complication outweighing the chances of spontaneous passage of the foreign body. Most of the endoscopic interventions are done as day procedures. Postinterventional care is straightforward and should be tailored to the specific need. Procedural complications include iatrogenic perforation, mediastinitis, or peri-oesophageal abscess formation. Antibiotics are administered only if complications are suspected. Rarely an abscess may need draining. Mortality rates from the procedure are currently reported at less than 1% by most centres [24, 25].  

..      Fig. 52.2  A retained pen in the stomach. There was no change in the position of the foreign body on a check radiograph 10 days after accidental ingestion

1. There may be more than one foreign body. This situation is more common and relevant with tracheobronchial foreign bodies, such as aspirated food items, nuts, and seeds. Therefore, a thorough assessment of the airway is important. 2. The grasping instrument’s hold on the foreign body should be assessed using the replica of the foreign body (if available), as ex vivo trial attempt, prior to attempting the actual retrieval. This helps in planning and avoiding any pitfalls and unnecessary attempts with an inappropriate grasping instrument. 3. The suction device “tip” should not be used to remove the object because it is not strong enough to hold the object during transit to the external world. 4. The dangerous end of sharp foreign bodies should be carefully covered by the scope (in case of a rigid scope) or a flexible endoscope protective sheath prior to removal (. Fig. 52.3). 5. Good haemostasis should be maintained. 6. Repeat inspection of the airway or digestive tract for any evidence of secondary or iatrogenic injury once the foreign body is retrieved.  

52.7  Practical Hints and Tips

The endoscopist must be aware of the following situations:

569 Aerodigestive Foreign Bodies in Children

..      Fig. 52.3  The protective sheath through which the different sizes of endoscopes can be easily guided. Preplacement of the protective sheath protects the oesophagus from accidental damage during retrieval of a sharp or pointed object

Key Summary Points 1. Inhalation or ingestion of a foreign body by a child is a common accident that may cause significant morbidity or even mortality. 2. The situation worsens when the foreign bodies are initially missed and then later the patient presents with pneumonia, atelectasis, abscess, or bleeds. 3. Radiography, fluoroscopy, bronchogram, CT, and MRI have all been used to make a confirmatory diagnosis. 4. Of utmost importance are a good history and clinical suspicion. 5. The treatment of choice remains endoscopic retrieval under general anaesthesia. 6. Success is ensured by careful assessment of the airways or oesophagus as well as foreign body size and shape prior to skilled endoscopy retrieval. 7. Special consideration should be given to hygroscopic foreign bodies in airways as well as batteries and magnets in gastrointestinal tract.

References 1. Cawthorne T. Diseases of the air and food passages of foreign body origin. By Chevalier Jackson M.D., Sc.D., and L. Jackson Chevalier A.B., M.D., W.B. Saunders & Co., Ltd., Philadelphia and London. 969 pages. 52s. 6d. J Laryngol Otol. 1936;51:824–5.

2. Boyd A, Chevalier D. Jackson: the father of American bronchoesophagoscopy. Ann Thorac Surg. 1994;57:502–5. 3. Steen KH, Zimmermann T. Tracheobronchial aspiration of foreign bodies in children. Laryngoscope. 1990;100:525–30. 4. Mu L, He P, Sun D. Inhalation of foreign bodies in Chinese children. Laryngoscope. 1991;101:657–60. 5. Berdan EA, Sato TT.  Pediatric airway and esophageal foreign bodies. Surg Clin North Am. 2017;97:85–91. 6. DeRowe A, Massick D, Beste DJ.  Clinical characteristics of aero-digestive foreign bodies in neurologically impaired children. Int J Pediatr Otorhinolaryngol. 2002;62:243–8. 7. Gupta P, Jain A. Foreign bodies in upper aero-digestive tract: a clinical study. Int J Res Med Sci. 2014;2:886. 8. Johnson K, Linnaus M, Notrica D.  Airway foreign bodies in pediatric patients: anatomic location of foreign body affects complications and outcomes. Pediatr Surg Int. 2016;33:59–64. 9. Messner AH. Pitfalls in the diagnosis of aerodigestive tract foreign bodies. Clin Pediatr. 1998;37:359–65. 10. Soepardi EA. Problems in managing foreign bodies in the upper aerodigestive tract. Med J Indonesia. 2002;11:15–8. 11. Digoy GP, Paul Digoy G. Diagnosis and management of upper aerodigestive tract foreign bodies. Otolaryngol Clin N Am. 2008;41:485–96. 12. Tan HKK, et al. Airway foreign bodies (FB): a 10-year review. Int J Pediatr Otorhinolaryngol. 2000;56:91–9. 13. Herdman RC, Saeed SR, Hinton EA. The lateral soft tissue neck X-ray in accident and emergency medicine. Arch Emerg Med. 1992;9:149–56. 14. Lue AJ, Fang WD, Manolidis S. Use of plain radiography and computed tomography to identify fish bone foreign bodies. Otolaryngol Head Neck Surg. 2000;123:435–8. 15. Koempel JA, Holinger LD. Foreign bodies of the upper aerodigestive tract. Indian J Pediatr. 1997;64:763–9. 16. Shergill GS, Nayak DR, Dora A, Shergill AK. Migrating foreign bodies in the upper aerodigestive tract: a surgical challenge. Case Rep. 2015;2015:bcr2015210326. 17. Briggs G, Walker RWM.  Retrieval of an endobronchial foreign body using a guide wire and angioplasty catheter. Anaesth Intensive Care. 2007;35:433–6. 18. Ginsberg GG. Management of ingested foreign objects and food bolus impactions. Gastrointest Endosc. 1995;41:33–8. 19. Friedman EM.  Tracheobronchial foreign bodies. Otolaryngol Clin N Am. 2000;33:179–85. 20. UpToDate. Paperpile. Available at: https://paperpile.­com/app/p/ dde0eadd-c8e1-001a-afa7-cb79610ab20f. Accessed 13 Nov 2018. 21. Swanson KL, Edell ES. Tracheobronchial foreign bodies. Chest Surg Clin N Am. 2001;11:861–72. 22. Vijaysadan V, Perez M, Kuo D.  Revisiting swallowed troubles: intestinal complications caused by two magnets–a case report, review and proposed revision to the algorithm for the management of foreign body ingestion. J Am Board Fam Med. 2006;19:511–6. 23. Parsons C, Singh S, Minocha A, Joshi A, Phelps S, Misra D, Cleeve S.  Multiple magnet ingestion in pediatric patients. The story so far....... Poster in BAPS conference Cardiff. 2015. 24. Hariga I, et al. Management of foreign bodies in the aerodigestive tract. Indian J Otolaryngol Head Neck Surg. 2014;66:220–4. 25. Arana A, Hauser B, Hachimi-Idrissi S, Vandenplas Y.  Management of ingested foreign bodies in childhood and review of the literature. Eur J Pediatr. 2001;160:468–72.

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Chest Wall Deformities Michael Singh and Dakshesh Parikh Contents 53.1

Introduction – 572

53.2

Pectus Excavatum – 572

53.3

Demographics – 572

53.4

Aetiology – 572

53.5

Clinical Presentation – 572

53.6

Investigations – 572

53.6.1 53.6.2 53.6.3

 ardiac – 572 C Respiratory – 572 Radiology – 572

53.7

Indications for Surgery – 574

53.8

Surgical Procedure – 575

53.9

Complications – 576

53.10 Bar Removal – 576 53.11 Outcomes – 576 53.12 Pectus Carinatum – 576 53.12.1 Introduction – 576 53.12.2 Aetiology – 577 53.12.3 Clinical Presentation – 577 53.12.4 Investigation – 577 53.12.5 Surgical Procedure – 577 53.12.6 Poland Syndrome – 578 53.12.7 Demographics – 578 53.12.8 Clinical Features – 578 53.12.9 Surgical Options – 578 53.12.10 Jeune’s Syndrome – 578 53.12.11 Sternal Cleft – 579

53.13 Evidence-Based Surgery – 579 References – 581 © Springer Nature Switzerland AG 2020 E.A. Ameh et al. (eds.), Pediatric Surgery, https://doi.org/10.1007/978-3-030-41724-6_53

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53.1  Introduction

patients are healthy and present because of the cosmetic deformity (. Fig. 53.1a). Patients often have a slouched posture, while young children have an associated protuberant abdomen. Almost a quarter of the cases is associated with scoliosis, and hence the spine should be examined in all cases. Several variations in the sternal abnormality have been described. A cup-shaped appearance describes an abnormality with localised, steeply sloping walls. A saucer-­shaped appearance is a diffuse and shallow sternal depression. A long asymmetrical trench-like deformity may also be found. Varying degrees of asymmetry of the chest wall may be present. Sternal torsion may be clinically obvious. A mixed carinatum/excavatum is an uncommon variation with the presence of a carinatum (protuberance) of the manubrium and excavatum of the sternum [4] (. Fig. 53.1b).  

Chest wall deformities are uncommon in the pediatric population. The majority of which are cosmetic, and therefore surgical correction is to improve the patient’s body image. The more common of these are: pectus excavatum, pectus carinatum and chest asymmetry. Rare abnormalities, such as Jeune’s syndrome and sternal clefts, have clinical consequences for the patient and therefore require surgery. 53.2  Pectus Excavatum

53

Pectus excavatum (PE) or funnel chest describes a posterior depression of the lower sternum and costal cartilages into the thoracic cavity. Most patients are asymptomatic and present because of the cosmetic appearance. The asymmetrical depression is not unusual and is associated with sternal torsion. The minimally invasive repair (MIR) or Nuss procedure, as described by Dr. Donald Nuss, has become the most accepted technique for its correction in developed countries [1, 2]. 53.3  Demographics

PE is an uncommon abnormality with an incidence of 38 and 7 per 10,000 births in the Caucasian and African populations, respectively. It is four times more common in males than females, with a family history of PE alone in up to 43% and in association with pectus carinatum in 7% [2, 3]. 53.4  Aetiology

The sternal depression is thought to result from asymmetrical growth of the costochondral cartilages. However, the exact aetiology is unknown. There is an association with connective tissue disorders, such as Marfan syndrome (21.5%) and Ehlers-Danlos syndrome (2%) [2]. 53.5  Clinical Presentation

Thirty percent of patients present in early childhood, with the majority presenting during the pubertal growth spurt. Common symptoms attributed to PE include: exercise intolerance, dyspnoea, chest pain with and without exercise and palpitations. The majority of

 

53.6  Investigations 53.6.1  Cardiac

Cardiac abnormalities have been known to be associated with PE and should be investigated in all cases with Electrocardiogram (ECG) and echocardiography. Compression of the right atrium and ventricle by the depressed sternum has been implicated to cause Mitral or Tricuspid valve prolapse in up to 17% of patients [2]. This has not been our experience in the United Kingdom. We have rarely found associated cardiac abnormalities in PE patients. Conduction abnormalities on ECG, such as right heart block, first-­degree heart block and WolffParkinson-White syndrome may be present in up to 16% of patients [3]. 53.6.2  Respiratory

Respiratory function should be assessed preoperatively at least with spirometry. Restrictive lung functions have been reported with decreases in FVC (77%), FEV1 (83%) and FEV25–75% (73%) [3]. It is useful to identify any underlying respiratory abnormalities prior to surgery both for anaesthesia and to see if correction results in improvement. 53.6.3  Radiology

Chest X-ray, both AP and lateral, is routinely performed so that it may help to define severity of the deformity and also help evaluate the thoracic spine

573 Chest Wall Deformities

a

b

c

..      Fig. 53.1  a Pectus excavatum severe deformity. b Mixed deformity with the presence of a carinatum (protuberance) of the manubrium and excavatum of the sternum

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a

b

53

c

..      Fig. 53.2  a Chest X-ray PA view showing shift of heart towards left and a line across the chest (AB) that can be used to calculate Haller index. b Lateral Chest X-ray showing the depth of sternal

depression (CD). c CT scan showing sternal torsion, asymmetrical chest and measure of Heller Index by calculating AB/CD

(. Fig 53.2a, b) [5]. CT scan of the chest has been considered the gold standard investigation in PE (. Fig  53.2c). It allows the calculation of the Haller index and transverse/AP diameter at the lowest point of the depression. Other information obtained includes the length of the depression, degree of sternal torsion and the presence of chest wall asymmetry [4]. We do not routinely carry out CT scan of the chest or calculate Haller index, as they do not influence the operative technique or outcome.

53.7  Indications for Surgery

 

 

Surgery for PE is carried out mainly for cosmetic reasons. However, in some severe cases, two or more of the following are considered indication for surgery [6]: 55 A Haller index of greater than 3.25 plus the presence of cardiac or pulmonary compression 55 Demonstrable cardiac abnormalities 55 Decreased pulmonary function 55 Previous failed repair: Ravitch or Nuss

53

575 Chest Wall Deformities

a

b

..      Fig. 53.3  a Markings on the chest wall. Lateral transverse incisions perpendicular to midaxillary line, incision for the thoracoport and the most elevated point in line with the deepest point of excava-

tum on the costal ridges. b Postoperative chest X-ray showing bar in position. c Long-term outcome after removal of Pectus “Nuss” bar

53.8  Surgical Procedure

The distance is measured between the midaxillary points at the deepest part of the sternal depression. One inch is subtracted from this measurement to get the length of the bar. The bar is then bent symmetrically into a semicircular shape. It is important to have a 2–4 cm flat segment at the centre of the bar to support the sternum. A slight overcorrection is advisable [2]. The most elevated point in line with deepest point of excavatum on the costal ridges is marked (. Fig 53.3a). Transverse incisions are made across the midaxillary line at the level of the lowest point of the depression bilaterally. A subcutaneous tunnel is dissected to the top of the ridges. A 5 mm thoracoscope is inserted into the interspace inferior to the proposed site of bar insertion on the right side. A pneumothorax is maintained at a pressure of 5–6 mmHg with a flow rate of 1–2 L/min. The rest of the procedure is performed under thoracoscopic visualisation. An introducer is then inserted from the right midaxillary incision along the previously created subcutaneous tunnel through the marked intercostal space (. Fig 53.3a). This introducer is used to carefully

The Nuss procedure is ideally performed between 10–12 years of age taking advantage of the pliability of the chest wall. However, the child in this age group is many a time immature and unable to make an educated decision. We believe that a child undergoing such a major procedure mainly for cosmetic reasons should be Gillick competent to give informed consent. There should be an honest discussion about the risks of surgery with the patient and their parents. A single bar achieves good correction at this age. Two bars are recommended for the postpubertal patient, long or extensive depressions or the presence of connective tissue disorders [6]. The patient is positioned supine with both arms abducted to 70–80° at the shoulder. Prophylactic intravenous antibiotics are given (Co-amoxiclav). An extensive skin preparation with an alcohol-based antiseptic solution of the anterior and lateral chest wall from the shoulders to the umbilicus is essential.

 

 

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dissect the space between the sternum and pericardium under thoracoscopic vision. The introducer is brought out through the left symmetrically opposite, previously marked intercostal space. After passing the introducer through to the opposite midaxillary incision, both ends of the introducer are lifted while the costal margins and flared ribs are pushed down. This corrects the deformity and loosens up the connective tissue around the sternum. An umbilical tape is attached to the end of the introducer and pulled across the retrosternal space by withdrawing the introducer. The bent bar is attached to the end of the tape and pulled into the chest, across the mediastinum and out through the left with the convexity facing posteriorly. The bar is then flipped using bar flippers so that the convex surface is facing the sternum. This produces an instant correction of the depression. A bar stabiliser is attached and sutured to the adjacent muscle with 1/0 polypropylene sutures. In addition, on the right side the bar can be fixed to the adjacent rib with pericostal 1/0 polypropylene sutures guided by thoracoscopy. The subcutaneous tissues and skin are closed. The lungs are expanded with positive pressures, and the pneumothorax is relieved by putting a 16Fr nasogastric tube underwater through a thoracoscopy port site [6]. A chest X-ray is obtained on day 1 postoperatively (. Fig 53.3b). Analgesia is maintained with epidural or a patient-controlled morphine infusion in combi­ nation  with Non-steroidal anti-inflammatory drugs (NSAIDs). A graded programme of incentive spirometry and physiotherapy is commenced postoperatively. The epidural or morphine infusion is usually stopped after the third postoperative day. Oral NSAID and Codeine may be required for up to 3 weeks postoperatively. Patients are advised to avoid sporting activity for 3 months postoperatively. This allows sufficient scar tissue to develop around the bar, thus fixing it in place and preventing displacement.  

53.9  Complications

In experienced hands, surgical complications are uncommon and are summarised in . Table 53.1. The majority of early postoperative complications can be managed conservatively [6]. Late postoperative complications are uncommon (. Table 53.1). Bar displacement is caused by inadequate fixation of the bar. Hence, it is recommended that the bar be fixed using a bar stabiliser and pericostal sutures. Persistent postoperative pain should be investigated for: bar or stabiliser displacement, a tight or too long bar, sternal or rib erosion, infection and bar allergy (Nickel) [6]. Cardiac injury during passage of the introducer is rare, but can be fatal. As this complication can have catastrophic consequences, it must be discussed with the patient during the initial consultation.  

 

..      Table 53.1  Early and late postoperative complications following Nuss bar insertion [6] Early postoperative complications

Late postoperative complications

Pneumothorax small; most common, conservative treatment

Bar displacement. Major displacement revision required

Pneumothorax large; chest drainage

Overcorrection

Horner’s syndrome; transient, epidural related

Bar allergy

Stitch site or wound infection

Recurrence

Pneumonia

Skin erosion

Haemothorax Pericarditis (postcardiomyotomy syndrome); oral indomethacin Pleural effusion; chest drainage

53.10  Bar Removal

The bar is generally removed after 2 years. However, in patients with connective tissue disorders, it should be left in for 3 years. Under general anaesthesia, both lateral incisions are reopened. All the sutures and scar tissue around the stabiliser and external surface of the bar are excised. The bar is straightened on both sides by using the bar reverse bender. Once reasonably loose, it is pulled out from the right side of the chest. The bar should not be forcibly extracted. In the event of difficulty, any residual scar tissue impinging on the bar should be excised before removal. Generally, bar removal is uncomplicated. A postoperative chest X-ray should be obtained to rule out pneumothorax. Generally, pneumothorax following bar removal is self-limiting and does not require any intervention [6]. 53.11  Outcomes

The long-term cosmetic results from the Nuss procedure are as follows: excellent 86%, good 10.3%, fair 2.4% and failed 1.3% (. Fig. 53.3c) [6].  

53.12  Pectus Carinatum 53.12.1  Introduction

Pectus carinatum (PC) or pigeon chest is a spectrum of anterior chest wall anomalies characterised by

577 Chest Wall Deformities

b

a

..      Fig. 53.4  a Pectus carinatum chondro-gladiolar deformity. b Postoperative result after correction of pectus carinatum

protrusion of the sternum and adjoining costal cartilages (. Fig  53.4a). The sternal (gladiolus) protrusion can be associated with symmetrical or asymmetrical protrusion of the lower costal cartilages. The other uncommon variant is the chondromanubrial protrusion of the manubrium, sternum and adjoining costal cartilages. There are varying degrees of asymmetry and tilting of the sternum with associated depression of the lower anteriolateral chest. The incidence of PC in our experience is equal to pectus excavatum; however, the literature suggest it to be less than that of PE. It is four times more common in males.

53.12.3  Clinical Presentation

 

53.12.2  Aetiology

The underlying aetiology for PC is similarly unknown and thought to be related to overgrowth of the costal cartilages. A familial incidence of PC is seen in up to 26% of patients. There is an association with connective tissue disorders, such as Marfan syn­ drome, s­ coliosis (34%) and congenital heart disease (6%) [7, 8].

Most patients present after 10 years of age when there is an increased prominence of the sternum during the adolescent growth spurt. Symptoms include: exertional dyspnoea, decreased exercise tolerance and precordial chest pain. The majority, however, present because of the cosmetic deformity. 53.12.4  Investigation

Either a PA and lateral chest X-ray or a CT scan will allow good visualisation of the extent of the abnormality. Any spinal abnormality should also be evaluated. The respiratory and cardiac functions should be assessed if necessary. The Haller index will be lower than normal (2.56) [7]. 53.12.5  Surgical Procedure

The most widely adopted surgical procedure was described by Ravitch. Either a transverse or chevron incision is made on the chest at a point that allows good

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access to the entire length of the deformity. In teenage girls, the incision can be hidden in the infra-mammary fold. The subcutaneous flaps are raised of the pectoralis major with diathermy superiorly to the manubrium and inferiorly to the rectus insertion. The medial attachments of the pectoralis major are incised, and the muscle is reflected laterally. Inferiorly, the rectus abdominis is detached from its costal insertions. The costal cartilages of the lower offending ribs on both sides are resected subperichondrally. Care is taken not to damage the underlying pleura. A transverse osteotomy is made in the anterior table of the sternum just proximal to the beginning of the sternal protrusion. By placing a wedge of resected cartilage into the osteotomy, the sternum can be further tilted down. The pectoralis and rectus muscles are approximated in the midline with a continuous suture. Inferiorly, the rectus abdominis is sutured to the pectoralis muscle margin. This helps to keep the sternum depressed in its new position. A suction drain may be used. The subcutaneous tissues and skin are closed. Postoperative analgesia is maintained by either an epidural or opioid infusion. The suction drains are removed once drainage has ceased [7]. Postoperative complications with the Ravitch technique are uncommon (11–22%). The reported complications following PC correction are: seroma, pleural effusion, pneumothorax and atelectasis. Hypertrophic scaring can occur in 15% of patients [7, 8]. Recently, external dynamic compression with a brace as the nonoperative treatment of PC has been described. The dynamic compression system (DCS) consists of a compression plate on a brace and harness. The plate and brace apply external anterior–posterior compression, to the still compliant chest wall, allowing its gradual remodelling over time. The patients have to wear the brace overnight and for as long as possible during the day (minimum 8–10  h). Patients are required to wear the brace for a minimum of 9 months. Complications occur in 12% of patients: back pain, skin ulceration and haematoma. Skin ulceration is managed by stopping the compression temporarily. Recurrence of PC has been reported in 15% during the rapid growth spurt. This can be treated with reuse of the DCS. Overall, good to excellent correction has been reported in 88% of the cases (. Fig 53.4b) [8].  

53.12.6  Poland Syndrome

Poland syndrome is a rare congenital malformation involving the chest wall and variable severity of other defects involving the areola, subcutaneous tissues, muscles, ribs, hand and heart. The extent of these defects varies significantly from the absent sternocostal head of the pectoralis major and/or minor with normal breast and underlying ribs to complete absence of anterior portions

of 2–5 ribs and cartilages. Breast involvement is frequent and is a disfiguring defect in girls. The hand deformity on the side of the defect is also associated in variable frequency from syndactyly to hypoplastic fingers [5]. 53.12.7  Demographics

The reported incidence of Poland syndrome is low, 1 in 30,000, and sporadic in nature. The exact aetiology of this defect is unknown. The proposed aetiology is a disruption in the subclavian arterial blood supply of the limb bud during the 6th fetal week [9, 10]. 53.12.8  Clinical Features

The anatomical abnormalities are usually unilateral. Clinically, these patients have absent anterior axillary fold, with the posterior axillary fold being easily visible from the front. The nipple and areola may be hypoplastic or absent, with deficient subcutaneous tissues. The chest is depressed on the affected side due to hypoplasia or absence of the underlying 2–4 or 3–5 ribs and cartilages. Rarely the lung may herniate through the defect in the chest wall giving a flail segment. This may cause respiratory distress in the new-born period. Dextroposition of the heart is common rather than dextrocardia in Poland syndrome. 53.12.9  Surgical Options

The surgical reconstruction options depend on the age of the patient and the extent of the defect. In the neonate, a flail chest may require reconstruction in order to provide a rigid support to counteract the paradoxical movement. Split rib grafts harvested from the contralateral unaffected ribs are generally preferred for the replacement of the missing medial aplastic ribs. The grafts are then attached to the lateral border of the sternum. A mesh sheath can also be used to help bridge large defects. In older patients, a latissimus dorsi muscle flap can be used to correct the defect in muscle mass or anterior axillary fold. For girls with breast hypoplasia, myocutaneous flaps or silicone implants can be used for postpubertal breast reconstruction. Various combinations of procedures may have to be used to achieve a satisfactory cosmetic result. 53.12.10  Jeune’s Syndrome

Jeune’s syndrome, also known as asphyxiating thoracic dystrophy, is a rare autosomal recessive disorder. It is characterised by dwarfism; foreshortened, horizontally

579 Chest Wall Deformities

placed ribs and short limbs. Thoracic cage abnormalities (Osteochondro-dystrophy) result in a markedly small chest, with severe restriction of expansion, pulmonary hypoplasia and severe respiratory distress. Its characteristic feature is a “bell-shaped” chest and a protuberant abdomen. The aim of surgery is to expand the chest wall and increase the thoracic volume, allowing lung expansion. Multiple surgical procedures have been described. Using a median sternotomy, the two halves of the sternum are stented apart using rib drafts or methyl methacrylate. Another option is dividing the ribs laterally in a staggered arrangement. The divided ribs are then fixed using titanium plates. This allows for gradual chest expansion. Recently, a form of expansion called thoracoplasty, which uses vertical expandable prosthetic titanium rib (VEPTR), has shown encouraging results. It allows for serial expansion of the thoracic wall. Despite these techniques, patients only have a modest improvement in respiratory function. The mortality rate from this condition still remains high [11]. 53.12.11  Sternal Cleft

Sternal clefts result from failure of fusion of the mesenchymal plate during the 8th embryonic week. The defect can be partial (superior or inferior) or complete. These rare abnormalities represent 0.15% of all chest wall anomalies [12]. The superior clefts consist of a “U”-shaped sternum with a bridge connecting both halves of the sternum inferiorly (. Fig  53.5a). There may be a scar on the overlying skin with varying degrees of herniation of the great vessels or heart. The inferior cleft consists of an inverted “V” defect with a midline cord-like scar running inferiorly to the umbilicus (. Fig 53.5b). Inferior clefts may also form part of the pentalogy of Cantrell. Cardiac pulsation may be seen through the defect. The complete cleft consists of two separated sternal bars. There is an association with congenital heart disease and craniofacial haemangioma. Preoperative investigations should include: ECG, ECHO cardiogram and 3D CT scan for complex defects (. Fig 53.5c). The aim of surgery is to provide protection for the mediastinum by bridging the defect. This also stops the paradoxical mediastinal movement with respiration and improves cosmetic appearance. The surgical procedure employed depends on the age of the patient. Surgical correction in the neonatal period is now preferred as the chest wall is more compliant, which allows for primary closure of the defect [13]. Access to the sternal bars is obtained by a midline incision and mobilisation of the skin and subcutaneous tissue flaps. The medial insertions of the pectoralis major and rec 

tus abdominis are mobilised and reflected. The medial perichondrium or periosteum is mobilised and approximated. For a neonatal repair of the superior sternal cleft, the inferior sternal bridge is excised, converting it to a complete cleft. Multiple lengths of absorbable sutures are then placed around both sternal bars. The sutures are the tied one at a time from inferior to superior. Collaboration with the anaesthetist is essential at this time as respiratory compromise may occur. A retrosternal drain is inserted, the rectus and pectoralis muscles are reattached and the subcutaneous tissues and skin is closed [14]. Older patients with a less-compliant chest wall require bridging the defect with autologous bone or artificial mesh. The defect is bridged using a cancellous bone graft from the iliac crest or split rib grafts [12, 13]. For wider defects, a combination of transverse rib struts covered by synthetic mesh can be used [12]. The long-term outcomes following sternal reconstruction are good. Some patients may develop in the long term mild pectus excavatum [12]. 53.13  Evidence-Based Surgery Title

Experience and Modification Update for the Minimally Invasive Nuss Technique for Pectus Excavatum Repair in 303 Patients.

Authors

Croitoru DP, Kelly RE Jr, Goretsky MJ, Lawson ML, Swoveland B, Nuss D

Institution

Department of Surgery, Children’s Hospital of the King’s Daughters, Norfolk, Virginia, USA.

Reference

J Pediat Surg. 2002;37:437–445

Problem

Blind passage of bar across the anterior mediastinum was previously done. Significant incidence of bar displacement due to inadequate fixation

Intervention

Introduction of thoracoscopy allows visualisation of introducer and bar during passage across anterior mediastinum. Introduction of bar stabilizers and pericostal sutures.

Comparison/control (quality of evidence)

No control group

Outcome/ effect

Very good cosmetic repair with this minimally invasive technique. Safer passage of bar across mediastinum with the use of a thoracoscope. Thus, preventing cardiac injury. Reduced incidence of bar displacement by using bar stabilisers and pericostal sutures.

Historical significance/ comments

This represents significant refinement of the operative procedure by the inventor, which has improved safety and reduced complications.

 

 

A large series by an expert in the procedure.

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a

b

53

c

..      Fig. 53.5  a Superior sternal “U” cleft deformity in a neonate. b Inferior Sternal cleft with diverification of recti and umbilical hernia. c 3 Dimensional CT scan of a 9-year-old girl, with a complete

sternal cleft repaired with a cancellous free bone graft from her iliac crest with very good result [13]

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Key Summary Points 1. Chest wall deformity is associated with cardiac, respiratory problems and connective tissue disorders. 2. Pectus excavatum, carinatum is essentially a cosmetic problem. 3. The minimally invasive repair is safe with low complication rates in experienced hands. 4. Thoracoscopy is strongly recommended while performing Nuss repair of PE 5. Other chest wall anomalies are rare and are best managed in specialist centres for optimal results.

References 1. Nuss D, Kelly RE Jr, Croitoru DP, Katz ME. A 10-year review of a minimally invasive technique for the correction of pectus excavatum. J Pediatr Surg. 1998;33:545–52. 2. Croitoru DP, Kelly RE Jr, Goretsky MJ, Lawson ML, Swoveland B, Nuss D.  Experience and modification update for the minimally invasive nuss technique for pectus excavatum repair in 303 patients. J Pediatr Surg. 2002;37:437–45. 3. Kelly RE.  Pectus excavatum: historical, clinical picture, preoperative evaluation and criteria for operation. Semin Pediatr Surg. 2008;17:181–93.

4. Cartoski MJ, Nuss D, Goretsky MJ, Proud VK, Croitoru DP, Gustin T, et  al. Classification of the dysmorphology of pectus excavatum. J Pediatr Surg. 2006;41:1573–81. 5. Mueller C, Saint-Vil D, Bouchard S.  Chest x-ray as a primary modality for preoperative imaging of pectus excavatum. J Pediatr Surg. 2008;43:71–3. 6. Nuss D. Minimally invasive surgical repair of pectus excavatum. Semin Pediatr Surg. 2008;17:209–17. 7. Fonkalsrud EW, Beanes S. Surgical management of pectus carinatum: 30 years’ experience. World J Surg. 2001;25:898–903. 8. Martinez-Ferro M, Fraire C, Bernard S. Dynamic compression system for the correction of pectus carinatum. Semin Pediatr Surg. 2008;17:194–200. 9. Folkin AA, Robicsek F.  Poland’s syndrome revisited. Ann Thorac Surg. 2002;74:2218–25. 10. Moir C, Johnson CH.  Poland’s syndrome. Semin Pediatr Surg. 2008;17:161–6. 11. Duncan J, Van Aalst J.  Jeune’s syndrome (asphyxiating thoracic dystrophy): congenital and acquired. Semin Pediatr Surg. 2008;17:167–72. 12. Acastello E, Majluf R, Garrido P, Barbosa LM, Peredo A. Sternal cleft: a surgical opportunity. J Pediatr Surg. 2003;38:178–83. 13. Abel RM, Robinson M, Gibbons P, Parikh DH. Cleft sternum: case report and literature review. Pediatr Pulmonol. 2004;37: 375–7. 14. Daum R, Zachariou Z. Total and superior sternal clefts in newborns: a simple technique for surgical correction. J Pediatr Surg. 1999;34:408–11.

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Mediastinal Masses Jonathan Karpelowsky, Jonathan Durell, and Kokila Lakhoo Contents 54.1

Introduction – 584

54.2

Demographics – 584

54.3

Pathology – 584

54.4

Clinical Presentation – 585

54.5

Investigations – 585

54.6

Radiology – 585

54.7

Laboratory Testing – 586

54.8

Histology – 586

54.9

Treatment – 586

54.10 Airway Management – 586 54.11 Definitive Management – 586 54.12 Postoperative Complications – 587 54.13 Prognosis and Outcome – 587 54.14 Evidence-Based Surgery – 587 Suggested Reading – 588

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54.1  Introduction

Mediastinal masses are a heterogeneous group of lesions that can provide significant diagnostic and management challenges to the pediatric surgeon. The lesions vary from slow-growing congenital cysts to aggressive neoplasms. The symptomatology can be quite varied, and a high index of suspicion needs to be maintained to make the diagnosis. 54.2  Demographics

54

Due to the variety of mediastinal masses, it is not possible to determine the true prevalence of these lesions. Each type of lesion, barring mediastinal lymphadenopathy, is quite uncommon. The spectrum of lesions seen on the African continent would include lesions traditionally seen in the developed world, but with infectious causes playing a much larger role in any differential diagnosis. Furthermore, the human immunodeficiency virus (HIV) epidemic has presented myriad presentations not previously seen.

..      Fig. 54.1  Normal thymus in the anterior mediastinum of a neonate

54.3  Pathology

Mediastinal masses can be practically classified by the lesion’s location within the mediastinum, namely, anterior, middle, and posterior. The location of the mass usually gives a good indication as to the differential diagnosis of the lesion. The anterior mediastinum extends from the inner aspect of the sternum to the anterior aspect of the trachea, pericardium, and great vessels. Its contents would include the thymus (. Fig.  54.1), ectopic thyroid or parathyroid, lymph nodes, and connective and adipose tissue. Thymic lesions would include hyperplasia (see . Fig.  54.1), cysts, thymoma, and thymic carcinoma. Disorders of the lymph nodes would be lymphoma (. Fig. 54.2), both Hodgkin’s and non-Hodgkin’s, and more recently an increasing number of patients with tuberculous adenopathy; germ cell tumours, both benign teratomas and malignant seminomas; and lymphatic anomalies, such as lymphatic malformations or lympahngiomas. Uncommon lesions include a retrosternal goitre or ectopic thyroid and malignancies of adipose tissue, a lipoblastoma. A Morgani diaphragmatic hernia would come to lie in the inferior anterior mediastinum and would thus be considered in the differential of lesions in this location. The middle mediastinum is situated from the pericardium anteriorly to the prevertebral fascia posteriorly. It  

 

 

..      Fig. 54.2  Anterior mediastinal mass (M) lymphoma

contains the major mediastinal viscera, including the oesophagus, trachea, heart, and great vessels. Minor constituents would be the paratracheal spaces and lymphoid tissue. Lesions would thus arise from the aforementioned disorders of the lymphoid tissue (i.e., lymphoma and tuberculosis); congenital anomalies of foregut development (i.e., bronchogenic and enteric, or duplication, cysts); and uncommon lesions related to the heart and pericardium.

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..      Fig. 54.3  Posterior mediastinal mass (neuroblastoma)

The posterior compartment contains the space between the trachea and the spine and the paravetebral sulcus on each side. The contents would include the thoracic spinal ganglia, the sympathetic chain, the proximal part of the intercostal vessels and nerves, lymphatics, and connective tissue. Consequently, lesions in this position are typically neurogenic in origin—namely, neuroblastoma (. Fig. 54.3), ganglioneuroma, neurofibroma, neurilemoma, paeochromocyctoma, and neuroenteric cysts. Other less common lesions would include a PNET (primitive neuroectodermal tumour) and hamartomas. Lastly, as for the mediastinal compartment, occasionally cystic lesions in the inferior posterior compartment may represent a sliding or paraoesophageal hiatus hernia. A further mechanism for classifying mediastinal masses are as cystic and solid. Cysts are usually congenital in nature. Cystic lesions would include bronchogenic, duplications neuro-enteric dermoids, lymphatic, and pericardial cysts. Solid masses are usually neoplasms, which may be benign or malignant, and are well detailed in the preceding section.  

ondary to a mass effect of the lesion on adjacent structures in the mediastinum. The symptoms, when present, are usually a cough, respiratory distress, wheeze, stridor, or dysphagia. In malignant mediastinal lesions, or occasionally tuberculous lymphadenopathy, children can present with a superior vena caval syndrome, representing both vascular and airway compression. Depending on the rate of growth of the lesions, the presentation may be insidious; in malignant lesions, however, it may occur over a few weeks, or in lesions complicated by superadded infection or haemorrhage, it may present as a life-threatening emergency over days or even hours. Posterior mediastinal lesions will usually present with pain secondary to bony erosions or neuralgia. Occasionally, with neurogenic tumours, patients may present with loss of power to the lower limbs and paraplegia secondary to a dumbbell lesion and cord compression. Neurological symptoms can be found with neuro-enteric cysts but usually take the form of recurrent meningitis and only rarely paraplegia. Systemic symptoms of loss of weight and night sweats are usually the initial symptoms for both tuberculosis (TB) and lymphoma. Differentiation between these two diseases in the African setting can often be difficult, especially in children coinfected with HIV. Both TB and lymphoma have an atypical and more aggressive course. In younger children, TB is the most common of the mediastinal lesions causing compressive symptoms of the airways. This is secondary to subcarinal and peribronchial nodes. In the clinical examination, it is important to pay attention to a systemic examination. Features of weight loss, lympahedenopathy, visceromegally, or skin lesions will all contribute to making the clinical diagnosis. A systematic approach to examination is important and can also provide a valuable alternative for a tissue diagnosis. 54.5  Investigations

Diagnostic studies will be directed by the type and severity of the symptoms and location of the mass.

54.4  Clinical Presentation

The location and the age of the patient are often the most useful factors in making a diagnosis. As discussed in the previous section, certain lesions have characteristic sites of occurrence. Mediastinal lesions are often asymptomatic; many of them are found on routine chest radiology (see . Figs.  54.1 and 54.3). Symptoms usually occur sec 

54.6  Radiology

The initial radiological workup will be the anteroposterior (AP) and lateral chest x-rays. An enormous amount of information can be gained from this affordable and widely available investigation (see . Figs.  54.1 and 54.3). Most important, one needs to assess the position  

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of the mass, especially on the lateral film, which would place it in either the anterior, middle, or posterior compartments. The airways can be well assessed by looking for compression and deviation of the trachea and major bronchi. In instances where dysphagia is a predominant symptom, a contrast swallow would be helpful to identify the location and extent of the oesophageal compression. In instances of foregut duplication, this will communicate with the normal oesophagus in 20% of the cases. The mainstay of investigation will be the computed tomography (CT) scan, which provides an excellent outline of the mediastinum and major airways (see . Fig. 54.2). It gives a precise relationship of the mass to the airway, oesophagus, and major vascular structures. In instances where one suspects a foregut duplication, imaging should continue into the upper abdomen, as these lesions may extend below the diaphragm. CT scans should be kept to an absolute minimum amidst concerns of radiation-induced neoplasia. In children who present with neurological symptoms, magnetic resonance imaging (MRI), where available, should strongly be considered, as—especially with dumbbell lesions—cord compression may be present. Occasionally, radioisotope studies may be required, notably a metiodobenzylgaunidine (MIBG) scan, which is both specific and sensitive for neuroblastoma or phaechromocytoma. The goal of the radiological work-up is to aid diagnosis and to help define the optimal surgical approach.  

54

54.7  Laboratory Testing

Specific laboratory tests can aid in the diagnosis of mediastinal masses. Serum lactate dehdrogenase (LDH) is a sensitive but nonspecific marker of lymphoma and neuroblastoma. Homovanillic acid (HVA) or vanillulmandelic acid (VMA) are both markers of neurogenic tumours, and these tests should be done in posterior mediastinal lesions. Finally, TB testing, either in the form of skin antigenicity (Mantoux or PPD—purified protein derivative) or white cell interferon-gamma testing (ELISpot or QuantiFERON®-TB Gold), should be performed. This testing must be correlated with the clinical picture— either induced sputum or gastric washings, depending on the age of the child. One note of caution: if TB is diagnosed, it can coexist with lymphoma, and hence failure to respond or progression on TB treatment should alert one to an alternative diagnosis.

54.8  Histology

Ultimately, treatment of solid mediastinal masses rests on the histological diagnosis. This is usually most pertinent to masses in the anterior mediastinum, where lymphoma is suspected. In these cases, peripheral nodes may provide the answer and avoid entrance of the thoracic cavity. In cases of smaller masses or cysts, excision biopsy can be done. 54.9  Treatment

The treatment for mediastinal masses ranges from curative excision to medical management, depending on the cause. In general, however, apart from lymphoma and TB, most lesions will require excision. 54.10  Airway Management

A compromised airway is often the reason for emergent presentation of these lesions. Airway compromise secondary to mediastinal lesions can be particularly difficult to manage, as the area of compression may often be at a carinal level and hence not alleviated by intubation or a tracheostomy. At presentation, patients may be unable to lie flat, and if given any sedation or anaesthetic, they will completely lose their airway. The best form of management would be avoidance of any sedation. Obtaining tissue under local anaesthetic from other sites is preferable. If this is not possible, then careful liaison with anaesthetic services and use of a CT scan best identify the degree and location of the compression. A rigid bronchoscope is a necessity, as it may be the only option to reestablish an airway distal to the carina. Full intensive-care facilities must be available. Discussion with oncology services should be undertaken to balance the risk of biopsy or empirical initial therapy to alleviate some of the airway compromise, with the disadvantage of losing valuable histological information. 54.11  Definitive Management

Surgical involvement is twofold: first, obtaining tissue for histology in unresectable lesions and second, for excision of cysts and masses. Careful attention needs to be paid to the access incision that is to be made. Anterior mediastinal lesions are best performed through a sternotomy and middle and posterior lesions via a posterior lateral thoracotomy.

587 Mediastinal Masses

Lesions that have a spinal component should either have a combined procedure, or alternatively have the spinal component done first, as failure to do so could result in paraplegia. In rare cases, thoracic foregut duplication cysts may transverse the diaphragm and end in the abdomen, requiring a combined abdominal and thoracic approach. Occasionally, surgical intervention will be required for node decompression in cases of TB. Thorascopic surgery offers an excellent diagnostic and therapeutic tool when available, but expertise and equipment may make this a limited option in most African settings. 54.12  Postoperative Complications

Postoperative complications are usually secondary to inadequate analgesia, resulting in pulmonary atelectasis. Incompletely excised lesions may recur, especially lymphatic malformations and malignant lesions. 54.13  Prognosis and Outcome

Generally, the prognosis for mediastinal masses is excellent. Mediastinal cysts that are excised offer complete cysts. Effective medical therapy for tuberculosis can prevent damage to the bronchi and distal lung. Malignant lesions would depend on the histology, but most of the lesions found in the mediastinum are responsive to chemotherapy.

..      Table 54.1  Evidence-based surgery Title

When Is a Mediastinal Mass Critical In a Child? An Analysis of 29 Patients

Authors

Lam JC, Chui CH, Jacobsen AS, Tan AM, Joseph VT

Institution

Department of Pediatric Surgery, KK Women’s and Children’s Hospital, Singapore

Reference

Pediatr Surg Int 2004; 20(3):180–184

Problem

The aims of this study were to determine the pattern of presentation of childhood mediastinal masses in our community and to identify factors associated with the development of acute airway compromise.

Intervention

The authors retrospectively reviewed the records of 29 consecutive patients with mediastinal masses managed at their institution between January 1995 and December 2001. Demographic data, mass characteristics, clinical presentation, and surgical procedures were recorded.

Comparison/control (quality of evidence)

Seven patients (24.1%) were asymptomatic at presentation. Eight (27.6%) were classified as having acute airway compromise at presentation. Respiratory symptoms and signs were the most common mode of presentation (58.6% and 55.2%, respectively). The most common histological diagnosis was neurogenic mass (37.9%), followed by lymphoma (24.1%). Most masses were located in the superior mediastinum (41.1%). Factors associated with the development of acute airway compromise were (1) anterior location of the mediastinal mass (P = 0.019); (2) histological diagnosis of lymphoma (P = 0.008); (3) symptoms and signs of superior vena cava syndrome (P = 0.015 and 0.003, respectively); (4) radiological evidence of vessel compression or displacement (P = 0.015); (5) pericardial effusion (P = 0.015); and (6) pleural effusion (P = 0.033).

Outcome/ effect

Clinical presentation of childhood mediastinal masses is often nonspecific or incidental. Yet they have the propensity of developing acute airway compromise, which is closely associated with superior vena cava obstruction. Such patients should be managed as a complex cardiorespiratory syndrome, termed “critical mediastinal mass syndrome,” by an experienced multidisciplinary team.

54.14  Evidence-Based Surgery

The wide spectrum of disorders that make up mediastinal masses do not lend themselves to comparative trials. Each of the neoplastic lesions (i.e., lymphoma, germ cell tumours, and neuroblastoma) have been extensively studied with respect to multimodal therapy, but these are not specific for mediastinal masses. The largest case series is that of Grosfeld et al. (see Suggested Reading). Most subsequent series focus on thorascopic approaches to these lesions. . Table 54.1 presents an analysis of mediastinal masses in 29 children. . Table  54.2 discusses a study of airway obstruction and management in mediastinal tumours.  

 

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..      Table 54.2  Evidence-based surgery

54

Title

Mediastinal Tumors—Airway Obstruction and Management

Authors

Robie DK, Gursov MH, Pokorny WJ

Institution

Cora and Webb Manning Department of Surgery, Baylor College of Medicine, Houston, TX

Reference

Semin Pediatr Surg. 1994;3(4):259–66

Historical Significance/comments

Large mediastinal masses can cause compression of surrounding mediastinal structures. Patients may have symptoms of airway obstruction or cardiovascular compromise. The additive effects of anaesthetics, paralysis, and positioning during biopsy can lead to acute airway obstruction and death. In some cases, tissue diagnosis can be achieved and treatment initiated without general anaesthesia. When general anaesthesia is necessary, specific measures should be taken to avoid disaster or immediately alleviate obstruction should it occur. Some patients at greatest risk will require pretreatment of the mass before tissue diagnosis. This article reviews these issues and provides a useful algorithm for managing patients with mediastinal masses.

Key Points 1. Mediastinal masses are presented by their anatomical location into anterior, middle, and posterior mediastina. 2. The location usually indicates the differential diagnosis. 3. Chest x-ray and CT scan are the most useful imaging modalities for mediastonal masses. 4. Most lesions require excision (except infective causes and lymphoma). 5. Airway management is paramount.

Suggested Reading Engum SA. Minimal access thoracic surgery in the pediatric population. Semin Pediatr Surg. 2007;16:14–26. Grosfeld JL, Skinner MA, et  al. Mediastinal tumors in children: experience with 196 cases. Ann Surg Oncol. 1994;1:121–7. Hammer GB. Anaesthetic management for the child with a mediastinal mass. Paediatr Anaesth. 2004;14:95–7. Jaggers J, Balsara K. Mediastinal masses in children. Semin Thorac Cardiovasc Surg. 2004;16:201–8. Williams HJ, Alton HM.  Imaging of pediatric mediastinal abnormalities. Paediatr Respir Rev. 2003;4:55–66.

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Chylothorax Andrew Grieve, Jonathan Durell, Jean-Martin Laberge, and Kokila Lakhoo Contents 55.1

Introduction – 590

55.2

Demographics – 590

55.3

Pathophysiology – 590

55.4

Aetiology – 590

55.5

Clinical Presentation – 591

55.6

Diagnosis – 591

55.7

Management – 591

55.7.1

Conservative – 591

55.8

Surgical Management – 592

55.9

Prognosis – 592

55.10 Conclusion – 592 References – 593

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55.1  Introduction

Chylothorax is a rare entity and is defined as an effusion of lymph in the pleural cavity. Chyle may have its origin in the thorax or in the abdomen or both. Leakage usually occurs from the thoracic duct or one of its main tributaries.

duct. Total protein content of thoracic duct lymph is also high. When chyle leaks through a thoracic duct fistula, considerable fat and lymphocytes may be lost. The thoracic duct also carries white blood cells, primarily lymphocytes (T cells)—approximately 2000–20,000 cells per milliliter. Eosinophils are also present in higher proportion than in circulating blood. Chyle appears to have a bacteriostatic property, which accounts for the rare occurrence of infection complicating chylothorax [4].

55.2  Demographics

55 9

There are no known racial, gender, age, or geographical variation to chylothorax. This is due to its aetiology [1]. Chylothorax is a common cause of a pleural effusion to result in respiratory compromise in a neonate. Yet the most common cause of a chylothorax is postcardiothoracic surgery [2] in children, with an increasing incidence reported of up to 6.6%. Risk factors in this group include subclavian vein thrombosis or damage to the thoracic duct. Congenital chylothorax may occur in 1: 6000–10,000 live births and is typically associated with either lymphatic malformations or in association with chromosomal anomalies, such as Noonan syndrome or trisomy 21. There is a slight male preponderance and right-sided chylothoracies are more common in the congenital variant. 55.3  Pathophysiology

The thoracic duct develops from outgrowths of the jugular lymphatic sacs and the cisterna chyli. During embryonic life, bilateral thoracic lymphatic channels are present, each attached in the neck to the corresponding jugular sac. As development progresses, the upper third of the right duct and the lower two-thirds of the left duct involute and close. The wide variation in the final anatomic structure of the main ductal system attests to the multiple communications of the small vessels comprising the lymphatic system. The thoracic duct originates in the abdomen, at the cisterna chyli, located over the second lumbar vertebra. The duct extends into the thorax through the aortic hiatus and then passes upward into the posterior mediastinum on the right before shifting toward the left at the level of the fifth thoracic vertebra. It then ascends posterior to the aortic arch and into the posterior neck to the junction of the subclavian and internal jugular veins [3]. The chyle contained in the thoracic duct conveys approximately three quarters of the ingested fat from the intestine to the systemic circulation. The fat content of chyle varies from 0.4 to 4.0 g/dl. The large fat molecules absorbed from the intestinal lacteals flow through the cisterna chyli and superiorly through the thoracic

55.4  Aetiology

Effusion of chylous fluid into the thorax may occur spontaneously in newborns and has usually been attributed to congenital abnormalities of the thoracic ducts or trauma from delivery. The occurrence of chylothorax in most cases cannot be related to the type of labor or delivery, and lymphatic effusions may be discovered prenatally [1]. Chylothorax in older children is rarely spontaneous and occurs almost invariably after trauma or cardiothoracic surgery; [2] however, some patients with thoracic lymphangioma may present in this older age group. Operative injury may be in part a result of anatomic variations of the thoracic duct. Neoplasms, particularly lymphomas and neuroblastomas, have occasionally been noted to cause obstruction of the thoracic duct. Lymphangiomatosis or diffuse lymphangiectasia may produce chylous effusion in the pleural space and peritoneal cavity. Extensive bouts of coughing have been reported to cause rupture of the thoracic duct, which is particularly vulnerable when full following a fatty meal. Other causes include mediastinal inflammation, subclavian vein or superior venacaval thrombosis, and misplaced central venous catheters (7 Box 55.1).  

Box 55.1  Causes of Chylothorax 55 Lymphatic malformation (nontrauma)

–– Thoracic duct atresia/aplasia/hypoplasia/ dysplasia –– Lymphangioma –– Lymphangiomatosis –– Intestinal lymphangiectasia (protein losing enteropathy) 55 Thoracic duct injury (trauma) –– Cardio-thoracic operations –– Esophageal atresia –– Diaphragmatic hernia –– Penetrating trauma (stab or gun-shot injury) 55 Malignant

591 Chylothorax

–– Lymphoma –– Kaposi sarcoma –– Mediatinal teratoma 55 Infectious –– Tuberculosis –– Filariasis –– Pneumonia –– Pleuritis and empyema 55 Idiopathic (associated with) –– Down syndrome –– Noonan syndrome –– Hydrops fetalis –– Turner syndrome –– Lymphedema 55 Miscellaneous –– Sarcoidosis –– Amylodiosis 55 Transudative –– Cirrhosis of the liver –– Heart failure –– Nephritic syndrome

55.5  Clinical Presentation

The accumulation of chyle in the pleural space from a thoracic duct leak may occur rapidly and produce pressure on other structures in the chest causing acute respiratory distress, dyspnea, and cyanosis with tachypnea. In the fetus, a pleural effusion may be secondary to generalized hydrops, but a primary lymphatic effusion (idiopathic, secondary to subpleural lymphangiectasia, pulmonary sequestration or associated with syndromes such as Down, Turner, and Noonan syndromes) can cause mediastinal shift and result in hydrops or lead to pulmonary hypoplasia. Postnatally, the effects of chylothorax and the prolonged loss of chyle may include malnutrition, hypoproteinemia, fluid and electrolyte imbalance, metabolic acidosis, and immunodeficiency. In a neonate, symptoms of respiratory embarrassment observed in combination with a pleural effusion strongly suggest chylothorax. Similar findings are noted in the traumatic postoperative chylothorax. In the older child, nutritional deficiency is a late manifestation of chyle depletion and occurs when dietary intake is insufficient to replace the thoracic duct fluid loss. Fever is not common.

..      Fig. 55.1  Right-sided congenital chylothorax in a newborn

reveals a clear straw-colored fluid in the fasting patient, which becomes milky after feedings. Analysis of the chyle generally reveals a total fat content of more than 400 mg/dl, a protein content of more than 5 g/dl, and a ratio of pleural fluid to serum cholesterol less than 1, and the presence of chylomicrons. In a fetus or a fasting neonate, the most useful and simple test is to perform a complete cell count and differential on the fluid; when lymphocytes exceed 80% or 90% of the white cells, a lymphatic effusion is confirmed; the differential can be compared to that obtained from the blood count, where lymphocytes rarely represent more than 70% of white blood cells. If chyle leak is noted at operation, the proximal and distal ends of the leaking duct should be ligated [5, 6]. Lymphangiography is useful for defining the site of chyle leak or obstruction with penetrating trauma, spontaneous chylothorax, and lymphangiomatous malformation. However, in a nontraumatized patient, the site of lymphatic leakage is often difficult to localize. Lymphoscintigraphy [7] may be an alternative to lymphangiography as it is a faster and less traumatic procedure. 55.7  Management 55.7.1  Conservative

55.6  Diagnosis

Chest roentgenograms typically show massive fluid effusion in the ipsilateral chest with pulmonary compression and mediastinal shift (. Fig.  55.1). Bilateral effusions may also occur. Aspiration of the pleural effusion  

Thoracentesis may be sufficient to relieve spontaneous chylothorax in occasional infants; however, chest tube drainage will be necessary for the majority. Further, tube drainage allows quantification of the daily chyle leak and promotes pulmonary reexpansion, which may enhance

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healing. Chylothorax in newborns [8] usually ceases spontaneously. In some cases of congenital chylothorax, supportive mechanical ventilation may be necessary because of insufficient lung expansion, persistent fetal circulation, or lung hypoplasia. In cases of severe chylothorax leading to nonimmunologic hydrops fetalis, antenatal management by intra-uterine thoracocentesis can be considered [9]. Since identifying the actual site of the fluid leak is difficult, surgery is often deferred for several weeks. Most cases of traumatic injury to the thoracic duct can be managed successfully by chest tube drainage and replacement of the protein and fat loss. Feeding restricted to mediumor short-chain triglycerides theoretically result in reduced lymph flow in the thoracic duct and may enhance spontaneous healing of a thoracic duct fistula. However, it has been shown that any enteral feeding, even with clear fluids, greatly increases thoracic duct flow. Therefore, the optimum management for chyle leak is chest tube drainage, withholding oral feedings and providing total parenteral nutrition (TPN) [10]. Cultures of chylous fluid are rarely positive; providing long-term antibiotics during the full course of chest tube drainage is not considered necessary. In nonresolving chylothorax subcutaneous injection of octerotide [11], a somatostatin analogue, at 10 μg/kd/ day in three divided doses is reported to have excellent result in a number of case reports and should be tried prior to surgical intervention. There has been demonstrated through numerous studies that conservative management is successful in >80% of cases. 55.8  Surgical Management

When chylothorax remains resistant despite prolonged chest tube drainage (2–3 weeks) and TPN, thoracotomy on the ipsilateral side may be necessary. The decision whether to continue with conservative management or to undertake surgical intervention should be based on the nature of the underlying disorder, the duration of the fistula, the daily volume of fluid drainage, and the severity of nutritional and/or immunologic depletion. Ingestion of cream before surgery may facilitate identification of the thoracic duct and the fistula. When identified, the draining lymphatic vessel should be suture ligated above and below the leak with reinforcement by a pleural or intercostal muscle flap. When a leak cannot be identified with certainty, or when multiple leaks originate from the mediastinum, ligation of all the tissues surrounding the aorta at the level of the hiatus provides the best results. Fibrin glue and Argon-beam coagulation have also been used for ill-defined areas of leakage or incompletely resected lympangiomas. Thoracoscopy may occasionally be used to avoid thoracotomy [12]. The leak, if visualized, can be ligated, cauterized, or sealed with fibrin glue. If the leak cannot

be identified, pleurodesis can be accomplished with talc or other sclerotic agents under direct vision through the thoracoscope, but this technique should probably be avoided in infancy because of the consequences on lung and chest wall growth. If there is concomitant chylopericardium, a pericardial window can be fashioned. Pleural peritoneal shunts have been reserved for refractory chylothorax [13–15]. A Denver double-valve shunt system is the type most commonly employed; it is totally implanted and allows the patient or parent to pump the valve to achieve decompression of the pleural fluid into the abdominal cavity where it is reabsorbed. 55.9  Prognosis

Prognosis largely depends on the aetiology of the chylothorax. Mortality rate of 12.8% among pediatric patients with a nontraumatic chylothorax has been reported. 55.10  Conclusion

Chylothorax may present as hydrops fetalis or mild respiratory distress. Although the majority of these lymph leaks resolve spontaneously, long-standing chylothorax leads to both nutritional and immunological deficiencies. Conservative medical therapy remains the mainstay of treatment, with surgical intervention required in refractory cases. Title

Chylothorax in Infants and Children

Authors

James Tutor

Institution

Department of Pediatric Pulmoanry Medicine, University of Tennessee Health Science Center, Memphis, Tennessee

Reference

Pediatrics. 2014;133(4):722–33

Problem

Review of the literature pertaining to the causes, diagnosis, management, and outcomes of congenital and traumatic chylothorax in children

Intervention

Literature review of the current methods of diagnosis and management of chylothorax

Comparision/ control

Literature review

Outcome/ Effect

Good review paper that is currently the most up-to-date with published views on the management of chylothorax

Significance

Comprehensive, up-to-date review of the management of the pediatric chylothorax

593 Chylothorax

Key Points 1. Chylothorax may be congenital or traumatic. 2. Diagnosis is by means of pleural tap analysis. 3. Optimum treatment includes chest tube drainage, nil by mouth and nutritional support with TPN. Feeding restricted to medium chain triglycerides may be tried in the absence of TPN. 4. Somatostatin analogue may be tried before surgical intervention. 5. Surgery is reserved for the refractory chylothorax with either ligation of the duct where feasible or utilization of a pleural peritoneal shunt.

References 1. Romero S.  Nontraumatic chylothorax. Curr Opin Pulm Med. 2000;6(4):287–91. 2. Chan EH, Russell JL, William WG, van Arsdell GS, et  al. Postoperative chylothorax after cardiothoracic surgery in children. Ann Thorac Surg. 2005;80(5):1864–70. 3. Levine C. Primary disorders of the lymphatic vessels–a unified concept. J Pediatr Surg. 1989;24(3):233–40. 4. Light RW. Chylothorax and pseudochylothorax. In: Pleural diseases. 3rd ed. Baltimore: Williams and Wilkins; 1995. p. 284–9. 5. Horn KD, Penchansky L.  Chylous pleural effusions simu lating leukemic infiltrate associated with thoracoabdominal disease and surgery in infants. Am J Clin Pathol. 1999;111: 99–104. 6. Staats BA, Ellefson RD, Budahn LL, Dines DE, Prakash UBS, Offord K.  The lipoprotein profile of chylous and nonchylous pleural effusion. Mayo Clin Proc. 1980;55:700–4.

7. Pui MH, Yueh TC. Lymphoscintigraphy in chyluria, chyloperitoneum and chylothorax. J Nucl Med. 1998;39:1292–6. 8. van Straaten HL, Gerards LJ, Krediet TG.  Chylothorax in the neonatal period. Eur J Pediatr. 1993;152(1):2–5. 9. Nygaard U, Sundberg K, Nielsen HS, Hertel S, et  al. New treatment of early felt chylothorax. Obstet Gynecol. 2007;109(5):1088–92. 10. Browse NL, Allen DR, Wilson NM. Management of chylothorax. Br J Surg. 1997;84:1711–6. 11. Cheung Y, Leung MP, Yip M. Octreotide for treatment of postoperative chylothorax. J Pediatr. 2001;139(1):157–9. 12. Christodoulou M, Ris HB, Pezzetta E. Video-assisted right supradiaphragmatic thoracic duct ligation for non-traumatic recurrent chylothorax. Eur J Cardiothorac Surg. 2006;29(5):810–4. 13. Robinson CLN. The management of chylothorax. Ann Thorac Surg. 1985;39:90–5. 14. Podevin G, Levard G, Larroquet M, Gruner M. Pleuroperitoneal shunt in the management of chylothorax caused by thoracic lymphatic dysplasia. J Pediatr Surg. 1999;34:1420–2. 15. Büttiker V, Fanconi S, Burger R. Chylothorax in children: guidelines for diagnosis and management. Chest. 1999;116:682–7.

Further Reading Bender B, Murthy V, Chamberiain RS.  The changing management of chylothorax in the modern era. Eur J Cardiothorac Surg. 2015;49(1):18–24. https://doi.org/10.1093/ejcts/ezv041. Downie L, Sasi A, Molhotra A. Congenital chylothorax: associations and neonatal outcomes. J Paediatr Child Health. 2014;50(3):234– 8. https://doi.org/10.1111/jpc.12477. Lopez-Gutierrez JC, Tovar JA.  Chylothorax and chylor ascites: management and pitfalls. Semin Pediatr Surg. 2014;23:298–302. https://doi.org/10.1053/j.sempedsurg.2014.09.011. Matsutani T, Hirakata A, Nomura T, et al. Transabdominal approach for chylorrhea after esophagectomy by using fluorescence navigation with indocyanine green. Case Rep Surg. 2014;2014:4. https:// doi.org/10.1155/2014/464017. Article ID 464017.

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Abdominal Wall Contents Chapter 56 Exomphalos and Gastroschisis – 597 Iyekeoretin Evbuomwan, Jonathan Durell, Kokila Lakhoo, and Abdelbasit E. Ali Chapter 57 Disorders of the Umbilicus – 605 Jean Heuric Rakotomalala and Dan Poenaru Chapter 58 Inguinal and Femoral Hernias and Hydroceles – 615 Francis A. Abantanga and Kokila Lakhoo

VI

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Exomphalos and Gastroschisis Iyekeoretin Evbuomwan, Jonathan Durell, Kokila Lakhoo, and Abdelbasit E. Ali Contents 56.1

Introduction – 598

56.2

Exomphalos – 598

56.3

Antenatal Diagnosis – 598

56.4

Aetiology/Pathophysiology – 598

56.5

Clinical Presentation – 598

56.6

Investigations – 599

56.7

Treatment – 599

56.8

Closure of Exomphalos Minor – 599

56.8.1 56.8.2

 rimary Closure – 599 P Delayed Primary Closure – 599

56.9

Closure of Exomphalos Major – 599

56.9.1 56.9.2 56.9.3 56.9.4

 rimary Closure – 599 P Staged Abdominal Wall Closure – 600 Secondary Abdominal Wall Closure – 600 Application of Silo – 600

56.10 Conservative Treatment – 601 56.11 Gastroschisis – 601 56.12 Antenatal Diagnosis – 601 56.13 Aetiology/Pathophysiology – 601 56.14 Clinical Presentation – 602 56.15 Management of Gastroschisis – 602 56.16 Evidence-Based Research – 603 Suggested Reading – 604

© Springer Nature Switzerland AG 2020 E.A. Ameh et al. (eds.), Pediatric Surgery, https://doi.org/10.1007/978-3-030-41724-6_56

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56.1  Introduction

The incidence of exomphalos and gastroschisis are roughly equal and the incidence of both conditions has been shown to be increasing globally; however, where antenatal diagnosis is available, there tends to be a higher rate of gastroschisis births due to the termination of foetuses with exomphalos. Reports show a uniform incidence of exomphalos and gastroschisis worldwide with no difference in regions, race, or social status. Gender incidence also appears equal. Although the incidence of umbilical hernia is largely more prevalent in people of African descent, this is not the case with exomphalos, which shows that they have different aetiological factors. When exomphalos is associated with other abnormalities, the aetiology is multifactorial and incidence varies with age of the mother. These abnormalities occur more in younger mothers; however, exomphalos as a lone pathology is more prevalent in older mothers.

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56.2  Exomphalos

Exomphalos is thought to be secondary to failure of the physiologically herniated small bowel to return to the abdominal cavity by the 12th week of gestation. The bowel is contained within a bilayer, amniotic, and peritoneal, sac in which the umbilical cord inserts. Depending on the size of the abdominal wall defect, other intraabdominal content may herniate into the sac, such as the liver, spleen, stomach, bladder, and gonads. 56.3  Antenatal Diagnosis

Antenatal diagnosis is possible on ultrasound studies performed following the first trimester. The importance of timing of the scan is that if performed too early, then it will be impossible to differentiate between a normal, physiological herniation and a true exomphalos. Antenatal detection allows for parental counselling and for planned delivery in a pediatric surgical centre. For large exomphalos, it may be preferred to deliver the baby by caesarean section to prevent rupture of the sac, which could occur during a normal vaginal delivery. 56.4  Aetiology/Pathophysiology

The pathophysiology of exomphalos is hypothesised to be related to the formation of the anterior abdominal wall and return of the midgut into the abdominal cavity. At the third week of gestation, three primitive divisions

of the gut are identifiable: foregut, midgut, and hindgut. By formation of the folds, intraembryonic coelom becomes gradually separated from extraembryonic coelom. The fold initially consists of ectoderm and endoderm. The mesoderm later forms in between, and the folds close in on the umbilical cord and thus complete the anterior abdominal wall. Failure of mesoderm development results in defects. At the cranial portion, the defect could affect the anterior wall of the chest (sternum, pericardium, and the heart, causing the classic features of the Pentalogy of Cantrell). In the caudal aspect of the anterior abdominal wall, the defect may be associated with bladder extrophy or varying degrees of anorectal anomalies. In the female, there may be a cloacal anomaly. Other anomalies that have been described as being associated include trisomy 13, 18, or 21 anomaly and the Beckwith-Wiedemann syndrome. The most common form is the central exomphalos, due to failure in the lateral folds. It may be classified in terms of shape, size, content, whether there are associated other anomalies, and whether the membrane coverage is intact or ruptured. More specifically: 55 Shape –– Conical: includes the hernia of the umbilical cord, usually small with broad skin edge diameter –– Globular: in which there is a large sac hanging on a relatively small diameter base and small abdominal cavity 55 Size of defect –– Diameter up to 5 cm, described as minor –– Diameter more than 5 cm, described as major 55 Content of the sac –– Bowel loops only, small and large intestine sometimes on part of the stomach, bladder, and occasionally the ovary –– Bowel loops and liver 55 Association with cardiac or other gross anomalies –– Syndromic –– Nonsyndromic 55 Membrane coverage –– Intact –– Ruptured membrane 56.5  Clinical Presentation

Exomphalos is an obvious abnormality in the newborn, presenting as a mass arising from a defect in the anterior abdominal wall covered by a membrane. The membrane is composed of an inner layer of peritoneum and an outer layer of amniotic membrane with Wharton’s jelly in between. It is attached by its base circumferentially to the skin of the anterior abdominal wall. The diameter of the base, the content of the sac, and the size relative to

599 Exomphalos and Gastroschisis

injury and infection by careful cleaning and administration of antibiotics. The primary aim of treatment of exomphalos is to return the bowel into the abdominal cavity and close the anterior abdominal wall. The possibility to do so will depend on whether the viscera can be placed in the abdominal cavity without tension on the anterior abdominal wall, without intraabdominal compartment syndrome, and without pressure on the diaphragm, which would impair respiration.

56.8  Closure of Exomphalos Minor 56.8.1  Primary Closure ..      Fig. 56.1  Exomphalos major

the size of the abdominal cavity will influence the decision for the method of management. Also important are whether the membrane is intact and whether the membrane or part of it is infected (. Fig. 56.1). Other features to be examined are the possible associated congenital abnormalities. Such features as ectopia cordis, sternal defect, bladder exstrophy, and anorectal anomaly are suggestive of a syndromic exomphalos. When loops of bowel are eviscerated, it is important to evaluate whether it is an exomphalos in which the membrane has ruptured or whether gastroschisis is the pathology.

Primary closure of the defect is possible in almost all cases of minor exomphalos. The membrane is cleaned and excised. The edges of the defect are determined, and the fascial edges are closed, followed by skin closure.

 

56.6  Investigations

Babies with exomphalos need close monitoring of glycaemia as these babies can become profoundly hypoglycaemic if the exomphalos is associated with Beckwith-Wiedemann syndrome. Other required investigations will be determined by evidence of associated anomalies. Abdominal ultrasound is used to ascertain the status of the renal tract, echocardiography to investigate for cardiac anomalies, and x-ray of the chest is used if there are signs relating to pulmonary anomalies. Chromosomal analysis is indicated for the aforementioned syndromic associations. 56.7  Treatment

At the initial management, it is important to pay attention to fluid management and ensure prevention of heat loss and hypoglycaemia which these babies are prone to (keep them warm and sweet is a mnemonic phrase). It is also pertinent to protect the sac from

56.8.2  Delayed Primary Closure

Primary closure may need to be delayed in minor exomphalos with an infected sac and oedematous abdominal wall. The sac is cleaned thoroughly, covered with Sofratulle® and gauze, and then wrapped with a soft crepe bandage. This is done daily, twice a day, morning and evening. If there is slough on the sac, the slough should be excised gently without causing bleeding. After 6 or 7 days, the exomphalos may be closed by excising the sac and closing the fascia and the skin. When closing the skin, an attempt should be made to construct a navel. 56.9  Closure of Exomphalos Major 56.9.1  Primary Closure

The abdominal cavity is closed with or without excision of the sac. During primary closure, it is important to exclude intraabdominal compartment syndrome, which is determined by poor urine output, tight abdominal cavity, respiratory compromise due to splinting of the diaphragm, and oedematous or dusky lower limbs due to poor venous return. The fascial layer and skin are closed separately, with possible construction of an umbilicus. Muscle flaps are sometimes created by making a release incision on the sides of the peritoneal cavity and mobilizing the muscle medially to obtain fascial closure.

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56 ..      Fig. 56.2  Traditional silo bag

56.9.2  Staged Abdominal Wall Closure

If closure of the fasciomuscular layer is not possible due to undue pressure on the diaphragm, only the skin may be undermined, stretched, and closed. This will heal, leaving a ventral hernia that can be closed at a later age. Postoperatively, the child is monitored for adequate respiration and urine output. Oral feeds are commenced as soon as the baby can tolerate them. Skin stretching may need to be attempted to increase the surface area of the abdominal wall. This is usually possible and reduces respiratory stress. Skin flaps are sometimes created by making release incisions on the sides of the abdomen and mobilizing the skin medially without attempting to appose the fascia and muscles.

identified. Any adherent viscera are released. The peritoneum is closed without tension. The fascia is then closed longitudinally with monofilament-­interrupted sutures. The effect of the closure on respiration should be monitored by the anaesthetist. If there is respiratory compromise, the sutures should be released and the use of a prosthetic material, such Prolene mesh, Gore-Tex, Surgisis, or Permacol, should be considered, followed by skin closure. 56.9.4  Application of Silo

Silo material is silicon or Prolene or other nonirritant synthetic material that is nonporous and not adhesive. The mesh is constructed into a bag to fit firmly around the bowels and sutured tightly to the circumference of the fascia and subcutaneous tissues of the defect (. Fig. 56.2). Bogota bags, intravenous solution bags, or blood bags may be used as silos. Preformed silo bags are now available that can be placed on the exomphalos and applied firmly on the circumference; however, these are expensive. The baby is nursed in an incubator in supine position with the bag suspended from the roof of the incubator. The baby is usually comfortable. Broad-spectrum antibiotics are administered. The circumference suture area is firmly packed and monitored for soaking, infection, or evidence of detaching. Over the days that follow, the bowel content gradually reduces into the abdominal cavity. The bag gets loose on the exomphalos. Further  

56.9.3  Secondary Abdominal Wall Closure

This is repair of the ventral hernia by achieving fascial closure with native body wall and, where not possible, the use of a prosthetic material (Gore-Tex®, Surgisis®, Permacol™), followed by skin closure. The general condition of the child must be good, with good nutritional status and haemoglobin of at least 10 gm/ dl. General anaesthesia is used. The scar of the healed exomphalos is excised. The skin is undermined, the fascial edge identified, and the fascia mobilised and muscle edge

601 Exomphalos and Gastroschisis

..      Fig. 56.3  Conservative management of exomphalos

..      Fig. 56.4  Ventral hernia formation

sutures or bands are then applied on the bag to keep it firm on the bowels; this may be required every 2 days. By 7–10 days, the exomphalos can be reduced sufficiently to enable closure. The most serious difficulties with silos are infection and detachment at the suture line.

56.11  Gastroschisis

56.10  Conservative Treatment

Conservative treatment involves nonoperative measures aimed at escharisation of the sac, which progressively contracts the scar, encouraging rapid epithelization from the edge. Various materials have been used, including mercurochrome solution, dilute silver nitrate solution, and 70–90% alcohol. The effect and complications on the baby have caused these solutions to be used less frequently. A useful method of conservative treatment is the application of closed dressing, which is applicable only for an intact sac. When the sac is ruptured, the silo is preferable. For the dressing, the whole abdomen is cleaned with a plain antiseptic lotion and dried. A layer of Sofratulle® is laid to cover the whole sac. Two or three layers of soft cotton gauze are placed to cover the whole lesion. A soft crepe bandage, 4 or 6 inches, is applied around the circumference of the abdomen, thus maintaining uniform pressure on the exomphalos (. Fig. 56.3). The dressing is kept on for 24–48 h and repeated with fresh materials. If the sac appears moist, the dressing should be done once every day. If there is evidence of infection, the dressing should be done twice a day. By this method, the baby can be kept in the hospital for a shorter time than for other methods, usually 7–10  days, and can be discharged to continue further dressing on an outpatient basis. By the time the exomphalos heals, there is a ventral abdominal hernia (. Fig.  56.4). This is repaired at a later stage, as described above.  

 

Gastroschisis is a herniation of small bowel through a full thickness defect in the anterior abdominal wall, usually to the right of the umbilicus. There has been found an association with young maternal age and the use of illicit drugs. Gastroschisis is not due to or associated with impaired organ formation, but there could be complications from mass protrusion of viscera through a small defect, including vascular compromise, which in early fetal life could result in bowel atresia. Gastroschisis has a better prognosis than exomphalos because the eviscerated bowel is usually a short loop of small intestine, the abdominal cavity would in most cases accommodate the herniated gut, and there are usually no other serious associated congenital abnormalities.

56.12  Antenatal Diagnosis

Gastroschisis is a condition that can be detected with antenatal ultrasound. Following the first trimester of pregnancy, the protrusion of bowel through the abdominal wall and into the amniotic cavity is the key to diagnosis. The antenatal detection allows for parental counselling for a planned delivery in a centre where prompt Pediatric surgical care can be given.

56.13  Aetiology/Pathophysiology

The pathogenesis of gastroschisis is related to the failure of development of the abdominal wall, resulting in herniation of the small bowel. The exact mechanism is unknown, the main hypotheses are a vascular accident

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..      Fig. 56.5 Gastroschisis

of the right omphalomesenteric artery and abuse of vasoactive drugs.

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56.14  Clinical Presentation

In gastroschisis (. Fig.  56.5), the eviscerated bowel segment is commonly loops of small intestine and colon, sometimes stomach. The umbilicus is attached to the normal site in an intact anterior abdominal wall, and the defect through which the bowel has herniated is usually in the right side of the umbilicus, separated from it by a small bridge of skin. As gastroschisis occurs early in intrauterine life, the bowel has been exposed to the amniotic fluid for a prolonged period. This results in the eviscerated loops usually being covered with a fibrinous exudate due to the amniotic fluid reaction.  

56.15  Management of Gastroschisis

A prolonged delay before surgical intervention results in extrusion of more loops of bowel, which may become oedematous and be complicated by gangrene. Resection of the gangrenous segment may result in a short length of small intestine. Also, management of the neonatal temperature and fluid balance is essential as the herniated bowel allows for repaid loss of heat and fluid. Most gastroschisis can be repaired by primary closure. The small defect is extended, and exploration of the abdomen is done to exclude gut anomalies, such as atresia or malrotation. The bowel is cleaned with warm

..      Fig. 56.6  Preformed silo

saline and reduced into the abdominal cavity, and the wound is closed. Another form of management is preformed silo application and gradual reduction of the bowel into the abdominal cavity over 24–72 h. The final closure of the abdominal wall consists of closing the defect with adhesive strips (i.e. Steri-strips). This allows the bowel to be returned into the abdominal cavity and defect closed without the need for a general anaesthetic (. Fig. 56.6). In the event of difficult primary reduction of the bowel and closure of the defect and in absence of expensive material, such as silo, intravenous solution bags or blood bags can be used as alternatives to provide coverage and allow gradual reduction of contents (. Fig. 56.7). Following reduction of the bowel into the abdomen, the baby should be closely observed for any signs of respiratory distress secondary to splinting of the diaphragm or signs of abdominal compartment syndrome.  

 

603 Exomphalos and Gastroschisis

a

b

d

e

..      Fig. 56.7  Use of a silo bag in the treatment of gastroschisis. a Showing a neonate with gastroschisis, b immediate postoperative view of the applied silo bag, c, d postoperative gradual reduction of bowel loops into peritoneal cavity, e day 10, immediate post-­

c

operative completion of bowel reduction and closure of the abdominal wall defect. (Source, with permission: Ali OM, Ali AE. Incidence, clinical presentation and outcome of gastroschisis and omphalocele in Sudan. Sudan Med J. 2014;50(2):75–80)

56.16  Evidence-Based Research Title

Abdominal Wall Defects: Prenatal Diagnosis, Newborn Management, and Long-Term Outcomes

Authors

Piergiorgio Gamba, Paola Midrio

Institution

Department of Pediatric Surgery, University Hospital, Padua, Italy

Reference

Semin Pediatr Surg. 2014;23(5):283–290

Problem

Literature review of congenital abdominal wall defects.

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Intervention

Reviews the antenatal diagnostics, the methods of managing these conditions, and what the outcomes are based on the known literature.

Comparison/control (quality of evidence)

Prenatal diagnosis of AWD is usually made by ultrasound screening in the late first trimester to midsecond trimester. An elevated maternal alpha feto protein level may be detected. Congenital omphaloceles are often associated with other anomalies, including chromosomal aberrations observed in 67–88% of cases with an impact on the outcome. Exomphalos minor (defect of 2–4 cm) can be delivered vaginally or by cesarian section. For large defect above 4 cm with liver, spleen, and small bowel protrusion, cesarian section at term is recommended. Foetuses with gastroschisis go into spontaneous preterm delivery more often than in the general population. They can be delivered vaginally. Surgical treatment of AWD is either by primary or staged delayed closure

Outcome/effect

In simple gastroschisis, primary reduction is accomplished in 70% of cases with quicker start of feeding and achievement of full feeds, lower complication rate, and shorter hospital stay. In complex cases with atresia, stenosis, perforation, or volvulus, all parameters are worse, including mortality. The outcome of the majority of patients affected by gastroschisis is good. Length of hospital stay can be up to a month. The incidence and morbidity of intestinal adhesions estimated as frequent as 27% in gastroschisis, with a mortality rate for bowel occlusion of 15%. Pregnancy is described in patients previously affected by gastroschisis. Testicles herniated from the defect and relocated into the abdomen at first operation may descend into the scrotum spontaneously in 50% of cases

Historical significance/ comments

This paper offers the latest literature review regarding the diagnosis, treatment, and outcomes of abdominal wall defects and allows for a comprehensive review of the topic.

Key Summary Points 55 Exomphalos has a sac and has associated abnormalities that contribute to the mortality and morbidity of the condition. 55 Gastroschisis has no sac and has no associated abnormalities, except possible bowel atresia. 55 Primary repair has the best outcome; however, if this is not possible, consider other modalities to avoid intraabdominal compartment syndrome. 55 Hypoglycaemia must be excluded in exomphalos.

Suggested Reading Lakshminarayanan B, Lakhoo K.  Abdominal wall defects. Early Hum Dev. 2014;90(12):917–20. Patel G, Sadiq J, Shenker N, Impey L, Lakhoo K.  Neonatal survival of prenatally diagnosed exomphalos and its management. Pediatr Surg Int. 2009;25(5):413–6. Sebakira J, Hadley GP.  Gastroschisis: a third world perspective. Pediatr Surg Int. 2009;25:327–9.

605

Disorders of the Umbilicus Jean Heuric Rakotomalala and Dan Poenaru Contents 57.1

Introduction – 606

57.2

Anatomy and Pathology – 606

57.3

Classification of Umbilical Problems – 606

57.4

Selected Umbilical Pathology – 606

57.4.1 57.4.2 57.4.3 57.4.4 57.4.5 57.4.6 57.4.7 57.4.8 57.4.9

 elayed Umbilical Separation – 606 D Omphalitis – 607 Umbilical Granuloma – 607 Dermoid Cyst of the Umbilicus – 608 Omphalomesenteric or Vitelline Remnant – 608 Umbilical Polyp – 609 Urachal Anomalies – 609 Umbilical Hernia – 610 Other Umbilical Problems – 612

57.5

Evidence-Based Research – 612 References – 613

© Springer Nature Switzerland AG 2020 E.A. Ameh et al. (eds.), Pediatric Surgery, https://doi.org/10.1007/978-3-030-41724-6_57

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57.1  Introduction

..      Table 57.1  Embryology and pathology of umbilical disorders

Umbilical disorders are frequently encountered by pediatric surgeons. In the newborn, the umbilical cord typically desiccates and separates within 3 weeks, leaving a dry, “star-like” central abdominal scar that forms the umbilicus. Failure of the umbilical ring to completely close can result in an umbilical hernia, by far the most common umbilical disorder. Discharge or abnormal tissue from the umbilicus is most often due to an umbilical granuloma, but can result from incomplete involution of the urachus or presence of an omphalomesenteric duct. Any discharge, mass, or sinus tract is pathological and should be appropriately evaluated and treated. These and other umbilical disorders are discussed in further detail in this chapter.

Embryological element

Normal remnant

Pathological abnormality

Two arteries

Para-urachal lateral ligaments

Single umbilical arterya

One vein

Round ligament of liver

Phlebitisb

Allantois

Median umbilical ligament

Patent urachus, urachal cyst or sinus

Vitelline duct

None

Omphalomesenteric duct remnant, umbilical polyp, Meckel’s diverticulum

Umbilical ring

Physiologic closure, fascia covering defect

Umbilical hernia Omphalocele

57.2  Anatomy and Pathology aTwenty-five

57

The umbilical cord is the main portal for entry and exit of blood from the placenta to the fetus during intrauterine life. In addition to the paired umbilical arteries and umbilical vein, the umbilical cord also contains the vitelline or omphalomesenteric duct (which connects the yolk sac to the midgut) and the allantois (the portion connecting the umbilicus to the bladder, becoming the urachus). Usually, the vitelline duct obliterates by the 5th to 9th week of gestation, and the urachus obliterates to become the median umbilical ligament by the 4th to 5th month. After birth, the umbilical cord withers and separates, leaving no remnants. Umbilical abnormalities can arise; however, when embryological remnants persist or fail to completely involute [1, 2]. . Table 57.1 compares the embryological components of the umbilical cord with related disorders. Like skin anywhere on the body, the umbilicus may also be affected by a variety of dermatological conditions, such as hemangiomas, dermoid cysts, or mechanical irritation. A number of syndromes, such as the Aarskog, Reiger, and Robinow syndromes, are associated with an abnormal umbilical appearance [3]. The umbilicus can also be found in an abnormal position or even absent, as in bladder exstrophy.  

57.3  Classification of Umbilical Problems

Umbilical problems can be classified as follows, based on the etiology of the abnormality: 55 Acquired: delayed umbilical separation, umbilical granuloma 55 Infectious: omphalitis, umbilical vein phlebitis

percent of umbilical disorders with single umbilical arteries have associated congenital anomalies. Source: Minkes R.K. Disorders of the umbilicus. EMedicine Specialties. Available at: 7 emedicine.­medscape.­com/article/935618overview; updated 27 October 2008 bA possible complication following umbilical vein catheterization  

55 Congenital: omphalomesenteric duct remnant, umbilical polyp, patent; urachus, umbilical hernia, dermoid cyst, umbilical dysmorphism 55 Neoplastic: rhabdomyosarcoma, teratoma 57.4  Selected Umbilical Pathology 57.4.1  Delayed Umbilical Separation

The timing of umbilical cord separation may vary, depending on ethnic background, geographic location, and method of cord care. Cord separation usually occurs 1 week after birth; persistence beyond 3 weeks is generally considered delayed. Various umbilical cord antiseptics can prolong the separation time, however. For example, triple dye may prolong separation of the cord for up to 8 weeks. Dry cord care has been found to be effective in developed countries [4]; however, in developing countries, antiseptic cord care continues to be recommended and has been found to decrease the incidence of and mortality from omphalitis [5]. Agents that have been used include 70% alcohol, silver sulfadiazine, chlorhexidine, neomycin-bacitracin powder, and salicylic sugar powder [6, 7]. Aside from agents used in umbilical cord care, other factors that can delay umbilical cord separation include

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infection, underlying immune disorders (such as leukocyte adhesion deficiency), or an urachal abnormality [7–10]. On examination, the skin surrounding the ­umbilical cord remnant should be carefully examined for an urachal remnant or for any evidence of infection. Omphalitis (see next section) can be rapidly progressive and life threatening in a neonate. A complete blood count with a differential may be useful as an initial screen for leukocyte adhesion deficiency. Even in the absence of infection, leukocytosis and neutrophilia may be present in patients with leukocyte adhesion deficiency [10]. Rare neutrophil motility defects may require a more sophisticated immunologic workup. If a patient presents with delayed separation of the cord, it may be either gently removed manually or divided just distal to normal skin with scissors or a scalpel. After removal, the stump site should be cleansed with an antiseptic agent and exposed to air. 57.4.2  Omphalitis

Omphalitis is an infection of the cord stump or its surrounding tissues. It presents most commonly in the newborn; the mean age at onset is 5–9  days or earlier in preterm infants. The risk of omphalitis is increased by a number of maternal factors (prolonged rupture of membranes, maternal infection, amnionitis), factors at delivery (nonsterile or home delivery, inappropriate cord care), and neonatal factors (low birth weight, delayed cord separation, leukocyte adhesion deficiency, neonatal alloimmune neutropenia). The incidence of omphalitis in developing countries is significantly higher (as high as 6%) than in developed countries (0.7%) [7]. Proper umbilical cord care is important in decreasing the incidence of omphalitis as well as neonatal tetanus (which may or may not be associated with omphalitis). Public health interventions have proven effective in decreasing the incidence and death from these infections. In Nepal, for example, the use of chlorhexidine decreased the incidence of omphalitis by 75% and its mortality by 24% compared to dry cord care [5]. Similarly, application of 4% Chlorhexidine (CHX) to the umbilical cord was effective in reducing the risk of omphalitis and neonatal mortality in rural Pakistan [11]. Therefore, and on the basis of the evidence, provision of CHX in birth kits might be a useful strategy for the prevention of neonatal mortality in high-mortality settings. More than a half million deaths occur yearly in newborn infants from neonatal tetanus. A high rate of neonatal tetanus was seen among the Maasai people in Kenya and Tanzania, who applied cow dung to the

umbilical stumps of their infants. In one simple health program among the Maasai people, the death rate from neonatal tetanus decreased from 82 per 1000 in control groups to 0.75 per 1000 in the intervention group [12]. Part of the success was in finding solutions that were culturally applicable and feasible (e.g., if clean water was unavailable, they advocated cleaning the stump with milk), obtaining support from within the community, and maintaining continued health promotion. Patients with omphalitis present with erythema, edema, and/or purulent drainage from the umbilical stump. Patients may also have systemic signs of sepsis, including lethargy, irritability, poor feeding, and fever or hypothermia. More extensive disease is seen with necrotizing fasciitis or myonecrosis and may also include a rapidly progressive cellulitis, a peau d’orange appearance, violaceous discoloration, bullae, crepitus, and petechiae. Patients with omphalitis should be admitted to hospital, and blood and wound cultures should be obtained. Omphalitis is usually polymicrobial; intravenous antibiotics covering gram-positive and gram-negative organisms should be initiated and the area of cellulitis marked and closely followed. Some authors also advocate anaerobic coverage, which certainly should be instituted if there is a concern for necrotizing fasciitis. Newborns with sepsis should also have a lumbar puncture and supportive care instituted. Patients with necrotizing fasciitis or myonecrosis require emergent and complete surgical debridement of all affected tissue, including preperitoneal tissue, the umbilical vessels, and the urachal remnant. Necrotizing fasciitis or myonecrosis can rapidly progress over a few hours; early and aggressive surgical treatment is critical to survival. Complications of omphalitis include umbilical phlebitis, portal vein thrombosis (which may lead to portal hypertension), liver abscesses, peritonitis, and necrotizing fasciitis or myonecrosis. The overall mortality of omphalitis is estimated at 7–15% and is significantly higher (37–87%) if complicated by necrotizing fasciitis or myonecrosis [13]. 57.4.3  Umbilical Granuloma

Umbilical granuloma is the most frequent cause of “wet umbilicus.” It presents as moist, raw, reddish-pink tissue arising from the base of the umbilicus after umbilical cord separation. An umbilical granuloma typically measures 0.1–1  cm in size and may be pedunculated. It is nontender (lacking innervation). Drainage may be clear or have the appearance of a fibrinous exudate. The tissue is friable and may bleed easily. Umbilical granuloma

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is due to the persistence of capillary and fibroblast cells, markers of an ongoing tissue growth. It may be difficult to distinguish from an umbilical polyp (discussed later in this chapter), which is usually brighter red, slightly larger, and represents remnant omphalomesenteric duct or urachal tissue [7, 8]. Management options for umbilical granuloma include repeated cauterization with silver nitrate, ligation, use of alcoholic wipes, or, rarely, surgical excision. Care must be taken in applying silver nitrate, as contact with normal skin can cause a chemical burn. If the lesion fails to resolve with silver nitrate, the diagnosis should be questioned because umbilical polyps, which may look similar to umbilical granulomas, do not respond to silver nitrate. If the lesion is excised, histology should be performed to rule out any retained omphalomesenteric duct or urachal remnants, which require further workup [1, 7, 14]. 57.4.4  Dermoid Cyst of the Umbilicus

57

Dermoid cyst of the umbilicus is a rare umbilical mass caused by inclusion of skin epithelium below or within the normal skin of the umbilicus. On examination, the umbilicus appears wider and darker in color than normal, and shiny. No inflammation is noted unless the cyst is infected. The diagnosis is made at surgery on finding the characteristic toothpaste-like sebaceous material within the umbilical mass. Surgical excision is curative. ..      Fig. 57.1  Omphalomesenteric fistula

57.4.5  Omphalomesenteric or Vitelline

Remnant

During early fetal development, the omphalomesenteric or vitelline duct serves as a conduit from the yolk sac to the midgut. It normally completely involutes by the 9th week of fetal life. However, a portion or all of the duct may fail to involute and present as one of the following: 55 An umbilical polyp, discussed in the next section. 55 Meckel’s diverticulum, in which only the diverticulum attached to the ileum has failed to involute. This is the most common vitelline remnant; it most often presents as a lower gastro-intestinal bleed caused by ectopic gastric mucosa, but rarely may present as diverticulitis, or it may function as the lead point for an intussusception. 55 A persistent congenital band, which can act as a fixed point around which an intestinal volvulus may occur. 55 A complete omphalomesenteric duct remnant with a patent conduit connecting the umbilicus to the ileum; this usually presents with pink mucosa protruding from the umbilicus (. Figs.  57.1 and 57.2) and  

..      Fig. 57.2  Omphalomesenteric fistula (intraoperative)

usually minimal but persistent discharge of intestinal contents or stool. 55 An omphalomesenteric duct cyst, in which the proximal and distal ends have obliterated but a

609 Disorders of the Umbilicus

remnant persists in between; this may present with an infection or obstruction and is quite rare. Diagnosis is generally made on physical exam. An ultrasound may show a loop of bowel present under the umbilicus but is not diagnostic and usually not necessary. A fistulogram may be helpful in clarifying the diagnosis. All omphalomesenteric duct remnants should be surgically resected. A Meckel’s diverticulum should be amputated at its base, the intestine closed transversely, and the vitelline artery ligated. A broad-based Meckel’s diverticulum may require a formal resection with a primary anastomosis. Meckel’s diverticula may contain ectopic gastric or pancreatic tissue on histology [1, 2, 7]. 57.4.6  Umbilical Polyp

An umbilical polyp (. Fig.  57.3) is a round, reddish mass at the base of the umbilicus that is comprised of embryologic remnants of the omphalomesenteric duct or, less commonly, of the urachus. It is often brighter red and slightly larger than an umbilical granuloma. Unlike a granuloma, it does not respond to silver nitrate and must therefore be surgically excised and histologically  

..      Fig. 57.3  Umbilical polyp

evaluated to confirm the diagnosis. If an umbilical polyp is diagnosed, further workup for an underlying omphalomesenteric duct or urachal remnant is warranted. One author reported a 30–60% chance of finding an underlying omphalomesenteric duct anomaly if an umbilical polyp was identified [1, 7, 10, 15]. 57.4.7  Urachal Anomalies

In the fetus the urachus is the embryonal duct connecting the dome of the urinary bladder to the umbilical ring. It is normally obliterated prior to birth, forming the median umbilical ligament. It forms in the preperitoneal space between the transversalis fascia and the peritoneum. Nonclosure of the entire tract leads to a patent urachus, whereas closure on the bladder side creates an umbilical sinus (. Fig. 57.4). Closure of both ends but patency of the tract in between may trap fluid in an urachal cyst (. Fig. 57.5), which is the most common urachal anomaly. A bladder diverticulum results when the distal tract involutes; it is the rarest urachal anomaly. Both a patent urachus and a urachal sinus may present with clear drainage from the umbilicus, and careful examination demonstrates a sinus at the base of the umbilicus. A patent urachus drains urine and may predispose to cystitis or recurrent urinary tract infections. A urachal cyst most commonly presents once it has become infected. An affected patient will present with infraumbilical swelling, abdominal pain, and erythema. The symptoms may mimic appendicitis. Patients with delayed separation of the umbilical cord may have a urachal anomaly [9]. Ultrasonography is often useful in diagnosing a urachal cyst and will show a cystic hypoechogenic lesion in the preperitoneal space. The presence of a longitudinal double line from the bladder dome to the umbilicus is  

 

..      Fig. 57.4  Urachal remnant

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cal defect has spontaneously closed, the nipple-like umbilical skin may continue to flatten, even during adolescence. 57.4.8.1  Etiology

An umbilical hernia results when the umbilical ring fails to close. Umbilical hernias are more frequent in premature, low-birth weight, and black infants. They also occur more often in children with ventriculoperitoneal shunts, ascites, obesity, and certain syndromes, including Beckwith-Wiedemann, Down, and Marfan syndromes. 57.4.8.2  Demographics

..      Fig. 57.5  Urachal cyst (intraoperative)

57

indicative of a urachal remnant. A sinogram may be used to identify the presence of a patent urachus or an urachal sinus. For a patent urachus, a voiding cystourethrogram (VCUG) should be obtained to exclude the presence of posterior urethral valves (back pressure from the distal obstruction may be keeping the urachus patent). Treatment involves complete resection of any part of the tract that has failed to completely obliterate. It is important to remove a cuff of bladder when excising the urachus to prevent the risk of developing a urachal adenocarcinoma later in adulthood [1, 2, 7]. This risk, however, is quite small, and asymptomatic and nonspecific urachal anomalies do not require resection, while symptomatic ones may be managed with initial observation for possible spontaneous resolution [16]. 57.4.8  Umbilical Hernia

An umbilical hernia is a full-thickness protrusion of the umbilicus with an associated fascial defect; it may contain peritoneal fluid, preperitoneal fat, intestine, or omentum. In children, umbilical hernias often close spontaneously. Small defects (2 cm). Meier et al. reported that umbilical hernias continue to close until the age of 14 years in African children [17]. The skin overlying an umbilical hernia may continue to stretch and result in a proboscoid umbilical hernia. In Africa, most parents are very accepting of its appearance, in contrast to parents from developed countries. Once the umbili-

Umbilical hernias are common in Africa. In one study from Nigeria, umbilical hernias were found in 91% of under-6-year-old, 64% of 6–9-year-old, and 46% of 10–15-year-old Nigerian children [18]. Meier found umbilical hernias with a fascial defect >1 cm in 23% of Nigerian children younger than 18  years old [17]. Surprisingly, when 6–9-year-old Nigerian children of high socioeconomic class were evaluated for an umbilical hernia, only 1.3% of 7968 children had an umbilical hernia [19]. It is possible that nutrition may be a factor; Jelliffe found a higher incidence of umbilical hernias in malnourished versus well-nourished adults (27% versus 14%) [18]. 57.4.8.3  Complications

Complications, including incarceration, strangulation, and rupture of umbilical hernias, may occur. In developed countries, the incidence of incarceration or strangulation is rare—one paper reported an incidence of 1 in 1500 umbilical hernias [20]. Rupture of umbilical hernias with evisceration is even more rare, but has been reported in infants younger than 6 months of age [21, 22]. Even though the incidence of incarceration and strangulation in children with umbilical hernias in Africa is not known, it appears to be higher than in the West (although this may in part reflect the significantly higher prevalence of umbilical hernias in black children). For instance, at A. Le Dantec Hospital in Senegal, over a 5-year period, 41 children had emergency operations for incarcerated or strangulated umbilical hernias [23]. At Jos University Teaching Hospital in Nigeria, over an 8-year period, 23 children underwent surgery for acute or recurrent incarceration [17, 21, 24–26]. In contrast, Okada et  al. reviewed the literature from 1957 to 1999 and found a total of only 38 cases reported in children worldwide [27]. In King’s College Hospital in London, only three incarcerated umbilical hernias were treated in children over a 20-year period

611 Disorders of the Umbilicus

..      Fig. 57.6  Giant ulcerated umbilical hernia

(and all three of these occurred in black children) [28]. The fact that most umbilical hernias in the West are repaired by 4–5 years of age does not account for the apparent difference in the frequency of incarceration between the West and Africa. In both Senegal and Nigeria, most of the incarcerations reported occurred in patients younger than 5 years of age; in Senegal, the average age at ­ incarceration was 14  months (range, 8 months–10 years); in Nigeria, the median was 4 years old (range, 3  weeks–12  years). Most incarcerated hernias do not have an inciting factor; however, bezoars, digested vegetable matter, parasitic worms, or ascites have been implicated [23, 24, 27]. Umbilical hernias can incarcerate regardless of the size of the fascial defect (. Fig. 57.6). In one report, a majority (52%) of the patients with incarcerated hernias had medium-sized (0.5–1.5 cm) fascial defects, whereas 24% occurred in small defects (1.5 cm) [27]. Of the incarcerated hernias in which a measurement was documented, in one study in Nigeria, all had defects greater than 1.5 cm in diameter (not all, however, were measured) [24].  

57.4.8.4  Management

Factors that lead parents to seek medical care for their children in Africa include the age of the child, size of the defect, height of protruding umbilicus,

and pain. On examination, a child with an umbilical hernia usually presents with a protrusion of the umbilicus with contents that are easily reducible. After reduction, the size of the fascial ring can be palpated; it can range in size from a few millimeters to more than 4  cm in diameter. No other investigations are required for diagnosis. Use of traditional remedies, such as fastening a coin or button over the hernia or using a band or other tight bindings to reduce the size of the hernia, are not recommended [29]. They are not beneficial and may prove to be harmful as they do not enhance closure of the umbilical ring and may lead to ulceration, erosion, or even hernia strangulation. Therefore, this practice is not justified for infants or children with umbilical hernia. Indeed, it should be avoided and discouraged. Umbilical hernia repair is one of the most frequent procedures performed by pediatric surgeons in highincome countries [1]. In Africa, however, umbilical hernia repairs are more infrequent because they are usually repaired only if symptomatic or complicated. Due to the high rate of spontaneous closure, conservative management of asymptomatic, easily reducible umbilical hernias is recommended. Surgical repair is generally recommended for hernias with large fascial defects (>1.5–2 cm), hernias that have failed to spontaneously close by 5–6 years of age, and umbilical hernias with significant proboscoid components. It is justifiable to close umbilical hernias with large ring defects in younger children if the child is having a general anesthetic for another procedure, such as an inguinal hernia repair [30]. A classic Mayo “vest-over-pants” procedure or simple approximation with long-lasting absorbable suture are both acceptable for conventional umbilical hernia repairs. For complicated umbilical hernia repairs, the use of mesh may be considered in the closure of a very large uninfected umbilical hernia to prevent excess tension on the fascia. The use of mesh also prevents the development of an abdominal compartment syndrome, which could result with significant fascial tension. Surgical complications are rare after umbilical hernia repairs. The outcome is excellent and the mortality approaches zero for elective repairs. Rare postoperative eviscerations can be prevented by meticulous surgical technique. As previously discussed, most African surgeons do not use the same indications for umbilical hernia repair as are used in developed countries. Instead, they recommend repairing only those umbilical hernias that are symptomatic in children. However, the

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incidence of incarceration or strangulation seems to be higher in Africa than in developed countries. Because of this, some African surgeons have recommended repairing all umbilical hernias in children [23]. Others, however, continue to recommend conservative treatment in spite of the risk of incarceration [17, 24]. Part of the rationale given is the wide prevalence of umbilical hernias. Even using selective criteria, Meier et  al. have estimated that if all umbilical hernias >1.5 cm were repaired in young children in Africa, about 6–8% of children younger than 4 years of age would require repair [17]; the volume of cases would likely outstrip available surgical resources. The exact criteria for elective repair on which Meier et  al. based their estimates were females older than 2 years of age and males older than 4 years of age with a fascial defect ≥1.5 cm in diameter; they estimated that 6% of 2-year-old females and 8% of 4-year-­ old males would need repair [17]. If hernias with large (>1.5  cm) fascial defects are indeed the most likely to incarcerate in Africa, as reported by Chirdan et  al. [24], one could argue that they should be repaired, as they are the most likely to incarcerate and the least likely to spontaneously close. Consideration should also be given to closing umbilical hernias in patients who live more than 1  h away from surgical resources. More research is necessary to determine the actual incidence of incarceration or ­strangulation and to clearly define which umbilical hernias are at greatest risk. Paraumbilical and supra-umbilical hernias should of course be excluded. Compared to umbilical hernias, they are unlikely to resolve spontaneously and have a higher tendency to develop complications; therefore, they generally require surgical repair. Perhaps it is time to reexamine how current recommendations for umbilical hernia repair in Africa were developed or became generally accepted. Are the current recommendations truly the best for the patient, preventing many children with umbilical hernias from unnecessarily undergoing the risk of a surgical procedure and anesthesia? Or did the current recommendations arise out of necessity, due to the wide prevalence of umbilical hernias, in an effort to strategically utilize surgical resources and time? If the latter is true, and umbilical hernias should be repaired using the same criteria as those used in developed countries, there may be other creative solutions. For instance, just as people have been specifically trained to suture lacerations or to perform caesarean sections, perhaps consideration should be given to specifically training people to perform simple, straightforward surgical procedures, such as umbilical hernia repairs.

57.4.9  Other Umbilical Problems 57.4.9.1  Absent Umbilicus

Malposition or absence of the umbilicus is encountered frequently in patients with bladder exstrophy. When the umbilicus is absent, an omphaloplasty may be performed, as many ethnic groups are culturally sensitive to the absence of the navel. Research has been performed to help the reconstructive surgeon locate the umbilicus in an aesthetically pleasing location [31]. 57.4.9.2  Stoma at Umbilicus

Some pediatric surgeons in the West have advocated placing intestinal or urinary stomas in the umbilicus primarily for aesthetic considerations. Experience with this in Africa has been limited, and no papers adopting its use in children have been published in Africa to date. 57.4.9.3  Gastroschisis and Omphalocele

These problems are discussed in 7 Chap. 56.  

57.5  Evidence-Based Research

. Table 57.2 presents results of a trial involving application of chlorhexidine to the umbilical cord to prevent omphalitis and neonatal mortality.  

..      Table 57.2  Evidence-based research Title

Topical Applications of Chlorhexidine to the Umbilical Cord for Prevention of Omphalitis and Neonatal Mortality in Southern Nepal: A Community-Based, Cluster-Randomised Trial

Authors

Mullany LC, Darmstadt GL, Khatry SK, et al.

Institution

Nepal Nutrition Intervention Project, Sarlahi, Kathmandu, Nepal; Institute of Medicine, Tribhuvan University, Kathmandu, Nepal; Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA

Reference

Lancet 2006; 365:910–918

Problem

Prevention of omphalitis and neonatal death related to umbilical cord care in southern Nepal.

Intervention

Topical application of chlorhexidine to the umbilical cord.

Comparison/control (quality of evidence)

Prospective, community-based, cluster-­ randomized trial.

613 Disorders of the Umbilicus

..      Table 57.2 continued Outcome/ effect

Compared to dry cord care, chlorhexidine reduced severe omphalitis by 75% and neonatal mortality by 24%.

Historical significance/ comments

Recent recommendations by the World Health Organisation for dry umbilical cord care may be inappropriate in developing countries, where the risk of omphalitis and death related to umbilical cord care is higher than in developed countries.

Key Summary Points 1. Appropriate umbilical cord care is important in preventing omphalitis, which can be a life-­ threatening infection. 2. The presence of a remnant of the urachus or omphalomesenteric duct should be considered if there is an umbilical sinus, persistent drainage, or remnant tissue. 3. Ultrasonography can be useful in investigating umbilical disorders when the diagnosis is uncertain. 4. Any irreducible umbilical mass or persistent umbilical lesion needs surgical exploration and resection. 5. Umbilical hernias are more common in children in Africa than in the rest of the world. 6. In Africa, proboscoid umbilical hernias are common, well-accepted, and treated c­ onservatively. 7. Incarceration or strangulation of umbilical hernias is uncommon but has been reported more often in Africa than in developed countries. Complications remain the general indication for umbilical hernia repair in Africa. 8. An omphaloplasty may be indicated for cultural reasons. 9. After umbilical surgery, the prognosis is excellent and complications are rare.

References 1. Snyder CL.  Current management of umbilical abnormalities and related anomalies. Semin Pediatr Surg. 2007;16:41–9. 2. O’Donnel KA, Glick PL, Caty MG.  Pediatric umbilical problems. Pediatr Clin North Am. 1998;45:791–9. 3. Friedman JM.  Umbilical dysmorphology. The importance of contemplating the belly button. Clin Genet. 1985;28:343–7. 4. Zupan J, Garner P, Omari AA.  Topical umbilical cord care at birth. Cochrane Database Syst Rev. 2004;(3):CD001075.

5. Mullany LC, Darmstadt GL, Khatry SK, et  al. Topical applications of chlorhexidine to the umbilical cord for prevention of omphalitis and neonatal mortality in southern Nepal: a community-­based, cluster-randomised trial. Lancet. 2006;365:910–8. 6. Pezzati M, Biagioli E, Martelli E, et al. Umbilical cord care: the effect of eight different cord care regimens on cord separation time and other outcomes. Biol Neonate. 2002;81:38–44. 7. Palazzi DL, Brandt, ML.  Care of the umbilicus and management of umbilical disorders. Available at: www.­uptodate.­ com (updated 13 Aug 2008). 8. Minkes RK. Disorders of the umbilicus. EMedicine specialties. Available at: emedicine.medscape.com/article/935618-overview (updated 27 Oct 2008). 9. Razvi S, Murphy R, Shalsko E, Cunningham-Rundles C. Delayed separation of the umbilical cord attributable to urachal anomalies. Pediatrics. 2001;108:493–4. 10. Pomeranz A. Anomalies, abnormalities, and care of the umbilicus. Pediatr Clin North Am. 2004;51:819–27. 11. Soofi S, Cousens S, Imdad A, Bhutto N, Ali N, Bhutta ZA. Topical application of chlorhexidine to neonatal umbilical cords for prevention of omphalitis and neonatal mortality in a rural district of Pakistan: a community-based, cluster-randomised trial. Lancet. 2012;379(9820):1029–36. https://doi.org/10.1016/S01406736(11)61877-1. Epub 2012 Feb 8. 12. Meegan ME, Conroy RM, Lengeny SO, et al. Effect on neonatal tetanus mortality after a culturally-based health promotion programme. Lancet. 2001;358:640–1. 13. Gallagher PG, Shah SS.  Omphalitis. eMedicine specialties. Available at: emedicine.medscape.com/article/975422 (updated 16 Jan 2009). 14. Daniels J, Craig F, Wajed R, Meates M. Umbilical granulomas: a randomised controlled trial. Arch Dis Child Fetal Neonatal Ed. 2003;88:F257. 15. Kutin ND, Allen JE, Jewett TC. The umbilical polyp. J Pediatr Surg. 1979;14:741–4. 16. Naiditch JA, Radhakrishnan J, Chin AC.  Current diagnosis and management of urachal remnants. J Pediatr Surg. 2013;48: 2148–52. 17. Meier DE, OlaOlorun DA, Omodele RA, et  al. Incidence of umbilical hernia in African Children: redefinition of “normal” and reevaluation of indications for repair. World J Surg. 2001;25:645–8. 18. Jelliffe DB. The origin, fate and significance of the umbilical hernia in Nigerian children (a review of 1,300 cases). Trans Royal Soc Trop Med Hyg. 1952;46:428–34. 19. Uba AF, Igun GO, Kidmas AT, Chirdan LB.  Prevalence of umbilical hernia in a private school admission-seeking Nigerian children. Niger Postgrad Med J. 2004;11:255–7. 20. Mestel AL, Burns H.  Incarcerated and strangulated umbilical hernias in infants and children. Clin Pediatr. 1963;2:368–70. 21. Ameh EA, Chirdan LB, Nmadu PT, Yusufu L.  Complicated umbilical hernias in children. Pediatr Surg Int. 2003;19:280–2. 22. Weik J, Moores D. An unusual case of umbilical hernia rupture with evisceration. J Pediatr Surg. 2005;40:E33–5. 23. Fall I, Sanou A, Ngom G, et al. Stangulated umbilical hernias in children. Pediatr Surg Int. 2006;22:233–5. 24. Chirdan LB, Uba AF, Kidmas AT. Incarcerated umbilical hernia in children. Eur J Pediatr Surg. 2006;16:45–8. 25. Mawera G, Muguti GI.  Umbilical hernia in Bulawayo: some observations from a hospital based study. Cent Afr J Med. 1994;40:319–23.

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26. Nmadu PT.  Pediatric external abdominal hernias in Zaria, Nigeria. Ann Trop Paediatr. 1995;15:85–8. 27. Okada T, Yoshida H, Iwai J, et al. Strangulated umbilical hernia in a child: report of a case. Surg Today. 2001;31:546–9. 28. Papagrigoriadis S, Browse DJ, Howard ER.  Incarceration of umbilical hernias in children: a rare but important complication. Pediatr Surg Int. 1998;14:231–2. 29. Salamon D, Cooper D editors, https://www.­healthguideinfo.­ com/digestive-disorders/p118752/ 2011. Accessed 4 Apr 2018.

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30. Minkes RK, Megison SM.  Disorders of the umbilicus treatment & management. https://emedicine.­medscape.­com/ article/935618-overview. Updated: Sept 27, 2017. Accessed 4 Apr 2018. 31. Abhyankar SV, Rajguru AG, Patil PA.  Anatomical localiza tion of the umbilicus: an Indian study. Plast Reconstr Surg. 2006;117:1153–7.

615

Inguinal and Femoral Hernias and Hydroceles Francis A. Abantanga and Kokila Lakhoo Contents 58.1

Introduction – 616

58.2

Demographics – 616

58.3

Inguinal Hernia – 616

58.3.1 58.3.2 58.3.3 58.3.4 58.3.5 58.3.6 58.3.7 58.3.8

E mbryology – 616 Pathophysiology – 617 Clinical Presentation – 618 History – 618 Physical Examination – 618 Investigations – 619 Treatment – 620 Postoperative Complications – 622

58.4

Femoral Hernia – 623

58.4.1 58.4.2 58.4.3 58.4.4 58.4.5

 etiology – 623 A Presentation – 623 Diagnosis – 623 Treatment – 624 Complications – 624

58.5

Hydrocele – 624

58.5.1 58.5.2 58.5.3 58.5.4

 etiology – 624 A Clinical Presentation and Diagnosis – 625 Treatment – 626 Postoperative Complications – 626

58.6

Prognosis and Outcome for Hernias and Hydroceles – 626

58.7

Prevention of Groin Hernias and Hydroceles – 626

58.8

Evidence-Based Research – 626 References – 627

© Springer Nature Switzerland AG 2020 E.A. Ameh et al. (eds.), Pediatric Surgery, https://doi.org/10.1007/978-3-030-41724-6_58

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58.1  Introduction

58

In general, a hernia is defined as the protrusion of an organ or a portion of an organ or tissue through an abnormal opening (defect) in the wall of the cavity containing it. In children, the abnormal defect in the anterior abdominal wall, which is congenital, is usually at the internal inguinal ring. Groin hernias and hydroceles are extremely common conditions in infancy and childhood and form a large part of the general pediatric surgical practice. Inguinal hernias (IHs) and hydroceles in infants and children are overwhelmingly congenital, although a vast majority are noticed after the neonatal period [1, 2]. Inguinal hernias and hydroceles share a similar aetiology and pathophysiology and may coexist [1]. Most hydroceles in infants and children rarely present as urgent problems. The vast majority of inguinal hernias in children remain in the inguinal region and do not descend into the scrotum; in the latter case, they are referred to as inguinoscrotal or complete inguinal hernias. Hydroceles, on the other hand, are scrotal masses. The diagnosis for both conditions is usually clinical; and the treatment for both conditions is surgery, especially in the case of the inguinal hernia  – it is on diagnosis when surgery is planned for the next elective surgery day. This is to prevent hernia complications, such as incarceration [3] (obstruction or strangulation), which is highest among infants [4], occurring any time during the life of the child. On the other hand, the hydrocele can be managed on the basis of watchful waiting till the child is about one and a half years old before hydrocelectomy is done – the preferred treatment for a hydrocele. Femoral hernias are rare in children, accounting for less than 1% of groin swellings in them. Preoperative misdiagnosis is common because their clinical presentation may mimic that of other groin masses. The result is a delayed diagnosis with an increased incidence of complications such as obstruction and strangulation. One has to have a high index of suspicion to be able to diagnose femoral hernias preoperatively and treat them early before any complications can occur and also to avoid carrying out inappropriate inguinal exploration. 58.2  Demographics

Groin hernias in children are mainly inguinal in nature (. Fig. 58.1). Inguinal hernias are indirect in more than 99% of cases as a result of the presence of a patent processus vaginalis (PPV). In about 0.5–1% of cases, inguinal hernias in children may be direct and are said to be due to the weakness of the floor of the inguinal canal or occur after surgery to correct indirect inguinal hernias. The direct inguinal hernia bulges through the inguinal floor medial to the inferior epigastric vessels in the  

Groin hernias Femoral hernia 0.5% Direct inguinal hernia 0.5–1.0%

Indirect inguinal hernia 99.0%

Inguinal

Reducible

Inguinoscrotal

Irreducible

Incarcerated

Strangulated

Obstructed

..      Fig. 58.1  Classification of groin hernias

Hasselbach’s triangle; the indirect hernia arises lateral to the inferior epigastric vessels. About 0.5–1% of groin hernias constitute femoral hernias [5, 6] (see . Fig. 58.1). Incidence data with reference to groin hernias and hydroceles are not available in the literature from Africa; most reports are hospital-based retrospective studies. Such data from Africa on inguinal hernias show a male-­ to-­ female ratio ranging from 2.2:1 to 16.6:1 [7–9]. The reported incidence of clinically apparent inguinal hernias in term babies in the world literature ranges from 1% to 5% in large pediatric series, with males outnumbering females by 3–10:1 [10, 11]. The incidence is considerably higher in premature babies [10], ranging from 7% to 35% [9, 10, 12]. Inguinal hernias are found variously on the right side in about 60–70% of cases and on the left side in 25–30% [13, 14]. They are bilateral in about 5–10% of cases [1].  

58.3  Inguinal Hernia 58.3.1  Embryology

The gonads develop along the urogenital ridge as retroperitoneal structures by the 6th week of gestation. The gonads are then differentiated into the testes or ovaries by the 7th to 8th week of intrauterine growth under hormonal influence. Retroperitoneal migration of the gonads, under the influence of hormones [1, 13], results in their being at the internal inguinal ring around the 12th to 14th gestational week. A gubernaculum, which is attached to the lower poles of the testes, is a condensation of mesenchyme that contains cord-like structures within it [13]. The gubernaculum appears to guide the testis into the scrotum. The testes remain quiescent at the internal inguinal ring until about 28 gestational

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617 Inguinal and Femoral Hernias and Hydroceles

weeks, when there is a rapid descent through the inguinal canal into the scrotum by the 36th to 40th week of intrauterine life. An outpouching of peritoneum precedes the descent of the gonad (testis) through the inguinal canal at the level of the internal inguinal ring. This outgrowth of peritoneum is referred to as the processus vaginalis (PV) in the male or the canal of Nuck in the female. As the testes descend, the PV is pushed ahead into the scrotum, and when descent is complete, the PV proximal to the testis obliterates either shortly before or just after birth, becoming a fibrous cord. This usually occurs later on the right side than the left, accounting for the greater frequency of hernias on the right. The portion of the PV adjacent to the testes remains patent and is referred to as the tunica vaginalis (which has a visceral and parietal layer) of the testes. In the female, the canal of Nuck ends in the labium majus and is also usually obliterated by the time of delivery of the baby.

As the testis descends into the scrotum, the layers of the anterior abdominal wall contribute to the formation of the layers of the spermatic cord. The transversalis fascia forms the internal spermatic fascia; the internal oblique and the transversus abdominis muscles form the cremasteric muscle; finally, the aponeurosis of the external oblique muscle contributes to the formation of the external spermatic fascia. 58.3.2  Pathophysiology

Failure of obliteration of the PV (or canal of Nuck) leads to the occurrence of hernias and hydroceles, the two most common problems of the region of the groin in children [1, 13]. The variety of degrees of patency of the PV accounts for the various pathologies seen in that region of the groin (. Fig.  58.2). Obliteration of the distal PV with the proximal portion still patent will lead  

I.I.R E.I.R

Vas Deferens

O.P.V

I.I.R

I.I.R

E.I.R

E.I.R O.P.V

Epididimymis TESTIS

TESTIS

TESTIS A. NORMAL ANATOMY. THE PV IS OBLITERATED

O.P.V

B. INGUINO-SCROTAL HERNIA

I.I.R

I.I.R

E.I.R

E.I.R

C. INGUINAL HERNIA

I.I.R E.I.R O.P.V

TESTIS TESTIS

TESTIS D. INFANTILE HYDROCELE I.I.R

TUNICA VAGINALIS

F. HYDROCELE OF THE SPERMATIC CORD E. VAGINAL HYDROCELE

E.I.R Vas Deferens

Epididimymis TESTIS

P.P.V

TUNICA VAGINALIS

G. PATENT PROCESSUS VAGINALIS ..      Fig. 58.2  Diagrammatic representation of different types of inguinal hernias and hydroceles in boys following the descent of the testes into the scrotum. a Normal anatomy: the PV is obliterated. b Inguino-scrotal hernia. c Inguinal hernia. d Infantile hydrocele. e

Vaginal hydrocele. f Hydrocele of the spermatic cord. g Patent processus vaginalis. Note: I.I.R. internal inguinal ring, E.I.R. external inguinal ring, O.P.V. obliterated processus vaginalis, P.P.V. patent processus vaginalis

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to intestines herniating into it, resulting in the formation of an indirect inguinal hernia confined to the inguinal region (see . Fig. 58.2c). In the case of complete failure of obliteration of the whole PV and in the presence of a wide neck, an inguinoscrotal (complete, scrotal) hernia will be the outcome (see . Fig. 58.2b). Congenital hydroceles formed after the failure of fusion of the PV may be communicating or noncommunicating (see . Fig. 58.2d–g). Where the opening of the PV that has failed to obliterate completely is narrow and will not allow intestines to herniate but permits peritoneal fluid to trickle into it, a communicating hydrocele will result. Noncommunicating hydroceles can be of three types: 1. Vaginal or scrotal hydrocele, is formed when the proximal portion of the PV obliterates completely, leaving the distal tunica vaginalis to fill with fluid 2. Infantile hydrocele, is formed when the proximal portion of the PV obliterates as far as the inguinal canal so that part of the PV is patent continuous with the tunica vaginalis 3. Encysted hydrocele of the spermatic cord, or simply hydrocele of the cord, is formed when there is complete involution of the proximal PV and the part above the tunica vaginalis, leaving an isolated cystic dilatation  

 

 

58

In the case of females in which the canal of Nuck is patent, a hydrocele or a hernia (usually containing intestine or ovary and fallopian tube) will form. It is important to remember that the mere presence of a PPV does not automatically mean a hernia or a hydrocele necessarily occurs. The PPV may take about a year or two in some instances to obliterate completely, but not all children with a PPV will develop a hernia or a hydrocele. Conditions associated with an increased risk of development of IH include positive family history, prematurity, low birth weight, undescended testes, hypospadias, epispadias, exstrophy of the bladder, ambiguous genitalia, ascites, gastroschisis, omphalocele, and male gender, among others. 58.3.3  Clinical Presentation

Inguinal hernias appear as intermittent, usually reducible, lumps in the groin (. Figs. 58.3 and 58.4) and are painless.  

58.3.4  History

A careful and accurate history is taken, followed by a meticulous examination of the child. There is usually a history (given by the mother or caregiver) of an asymptomatic bulge or mass in the groin or scrotum or labia, which is intermittent and originates from the internal

..      Fig. 58.3  Bilateral reducible hernias. Both testes are in the scrotum

..      Fig. 58.4  Reducible left inguinoscrotal hernia

inguinal ring. The mass appears on crying in the infant or younger child; in the older child, it may appear with coughing or walking or playing around (i.e., on increasing the intraabdominal pressure). Also, of note in the history is that the bulge varies in size; it may periodically disappear spontaneously (when the contents completely return to the peritoneal cavity) or by application of gentle pressure by the parent. The mass usually does not cause pain or much discomfort to the child. Often the caregiver or the older child can point to the exact location of the bulge. Most hernias are seen in the first year of life, often when the parents are changing the diaper of a crying or straining child or bathing the child. 58.3.5  Physical Examination

The history of a mass should be confirmed by examining the child in various positions, upright or supine. It is important to ascertain that the testes are in the scrotum

619 Inguinal and Femoral Hernias and Hydroceles

because a retractile testis will mimic an inguinal hernia by causing a bulge at the external inguinal ring. One of the following procedures will increase the intraabdominal pressure in order to augment the demonstration of a groin mass. 1. Lie the infant supine with the hands held above the head and the lower limbs held straight down. This can be done by an assistant or the parent. This makes the child strain or cry, thus increasing the intraabdominal pressure and causing the bulge to appear if it is actually present. Standing the patient upright may help at times. 2. Ask the older child to jump or bounce up and down, which may allow the mass to appear in the inguinal region. 3. Ask the older child (>6  years of age) to cough or blow up a balloon. This will make the bulge appear. (Often, children 25  ml of fluid from the stomach via a nasogastric tube is very suggestive of

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obstruction. Antenatal ultrasound scanning may show dilated loops of bowel with vigorous peristalsis, which is diagnostic of obstruction. Polyhydramnios may develop but is more commonly seen in duodenal and esophageal obstructions. The more distal the atresia, the more generalized the abdominal distension. After aspiration of gastric contents, the abdomen will be less distended and visible peristalsis may be observed. There is a failure to pass meconium, and typically small volume gray mucoid stools are passed. Abdominal tenderness or peritonitis only develops with complications of ischemia or perforation. This commonly occurs with delay in diagnosis and is due to increased intraluminal pressure from swallowed air and secondary volvulus of the bulbous blind-­ ending bowel at the level of the first obstruction. 63.5  Physical Examination

Findings on physical examination are frequently not very revealing. Most patients will have some degree of abdominal distension. The amount of distension will vary depending on the level of obstruction. Patients generally do not have abdominal tenderness or an abdominal mass. Therefore, the presence of these findings suggests a complicated obstruction associated with ischemia or prenatal perforation, or that the cause of obstruction is malrotation with midgut volvulus. 63.6  Investigations

In most patients, a simple abdominal x-ray with anteroposterior and either cross-table or left lateral decubitus projection are adequate to make the diagnosis based on the presence of dilated air-filled intestinal loops and air– fluid levels (. Fig. 63.2). In addition, plain abdominal x-rays will suggest the level of obstruction based on the number of dilated bowel loops. The presence of multiple dilated bowel loops without air–fluid levels suggests the possibility of meconium ileus, particularly if the intestinal content has a “ground glass” appearance. Presence of a single and very dilated loop with a large fluid level is often indicative of colonic atresia. The differential diagnosis includes other causes of intestinal obstruction in the neonate. In patients with evidence of a proximal complete obstruction, the differential diagnosis is limited, and no additional diagnostic studies are required. In patients with multiple dilated bowel loops suggesting a distal obstruction, the differential diagnosis includes several conditions for which surgical intervention may not be required. Therefore, in these patients, a contrast enema may be helpful to look for evidence of meconium plug or meconium ileus which may respond to nonoperative managements. In addi 

..      Fig. 63.2  Abdominal radiograph showing several dilated gas-­ filled loops in a jejunal atresia

tion, a contrast enema may demonstrate findings suggestive of Hirschsprung’s disease, which would direct initial management toward obtaining confirmatory tests for this disease. Contrast enema showing a patent colon is helpful in that demonstration of colonic patency by injection of saline at operation, a sometimes tedious procedure, is not required (. Fig. 63.3). In patients with intestinal stenoses, plain abdominal x-rays may demonstrate proximal bowel dilation; however, in most patients, a gastrointestinal contrast meal or enema is required to confirm and locate the site of partial obstruction.  

63.7  Management

All patients should receive judicious fluid hydration prior to operative intervention. In addition, a nasogastric or orogastric tube should be passed to empty the stomach and decrease the risk of vomiting with aspiration. In general, patients with intestinal atresias have a low risk of associated cardiac anomalies, so that preoperative special investigation is not required unless the patient has clinical evidence of a serious cardiac defect.

667 Intestinal Atresia and Stenosis

may result in delayed intestinal function and problems with bacterial overgrowth. Therefore, in patients with a relatively short segment of severely dilated proximal intestine, resection of the dilated segment with re-establishment of continuity by end-to-end anastomosis is a good option. However, in patients with long segments of proximal intestine that are significantly dilated, resection of the whole involved segment may result in inadequate remaining intestinal length to allow absorption of enteric nutrients (i.e., short-bowel syndrome). Therefore, these patients frequently are treated by either imbrication or tapering enteroplasty of the proximal dilated segment. To date, no randomized studies have compared the outcomes for patients with intestinal atresias with or without the addition of an enteroplasty or plication, but imbrication tends to result in recurrence of dilatation and dysmotility. In patients where the atresia is just distal to the duodenojejunal flexure, it may be advantageous to resect the dilated bowel, de-rotate, and taper the duodenum with primary anastomosis. This facilitates passage of a trans-anastomotic feeding tube and early restoration of foregut function. The total residual length of bowel should be measured with a tape and recorded, as this gives some guidance as to prognosis. Patients who have multiple atresias (type IV) or an apple-peel deformity (type IIIb) (. Figs. 63.5 and 63.6) are particularly challenging management problems. These patients may require multiple anastomoses and frequently will experience long-term delays in return of intestinal function. In addition, many of these patients will have short-bowel syndrome due to inadequate residual intestinal length. In general, the formation of stomas is unnecessary and should be avoided as dilated bowel does not reduce in caliber and fluid and electrolyte losses may be severe. While most centers still perform surgery via a laparotomy, circumumbilical incision as well as laparoscopic-­ assisted surgical techniques are gaining popularity, and in centers where there is adequate experience and equipment, the cosmetic outcomes are improved with little effect on the functional outcomes as long as the basic principles discussed above are adhered to. Where short-bowel syndrome is evident, it is advised to perform a primary end-to-end anastomosis and allow for adaptation to progress before intervening surgically at a later stage outside the neonatal period rather than embark on primary autologous intestinal reconstructive surgery (AIRS) such as the serial transverse enteroplasty procedure (STEP) or lengthening and tailoring procedures (LILT, Bianchi) as these have no defined place at the initial operation. In the African setting, however, this approach may not be feasible due to the fact that TPN is not universally available.  

..      Fig. 63.3  Contrast enema showing normal colon with dilated proximal small bowel in an infant with jejunal atresia

At exploration, usually via a transverse supraumbilical incision or periumbilical approach, the site of the most proximal atresia is readily identified as the site of marked change in intestinal caliber. The outer wall of the intestine at the site of obstruction may appear intact, or there may be an associated defect in continuity of the intestine and the mesentery (. Fig.  63.4). Generally, surgical treatment requires excision of the ends of the intestine involved in the atresia. It is also important to look for distal sites of obstruction which can occur in up to 20% of patients and may not be immediately obvious due to lack of caliber change beyond the proximal atresia. These distal points of obstruction can be identified by flushing the distal intestinal lumen with saline to confirm intestinal continuity to the level of the rectum. After resection of the atretic segment, the surgeon is faced with the difficult task of re-establishing continuity between intestinal segments with marked size discrepancies. Another consideration is the potential dysmotility of the proximal markedly dilated segment, which  

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a

b

63

..      Fig. 63.4  Type I jejunal atresia. Membrane occlusion without mesenteric defect or loss of intestinal length a and the cut surface at surgery showing the occluding membrane b

63.8  Postoperative Complications

The most common postoperative complication is a functional obstruction at the site of anastomosis [8]. Unfortunately, this complication may be due to the underlying intestinal dysmotility associated with this anomaly and may not be preventable by changes in surgical technique. Other less commonly observed complications include anastomotic leak and adhesive obstructions. Obstructions due to missed distal unrecognized atresias should not occur and can be prevented by proper evaluation at the time of the initial operation. 63.9  Prognosis and Outcomes

..      Fig. 63.5  Type III b atresia. Note the proximal jejunal atresia, malrotation, and mesenteric defect with a single artery of supply from the middle and right colic vessels with significant loss of intestinal length

Most patients with intestinal atresia do not have associated life-threatening anomalies. Therefore, the primary factor that impacts mortality is ability to support the nutritional needs of the patient during the postoperative period while awaiting adequate bowel function to allow enteral alimentation. [9] In centers where parenteral nutritional support is feasible, these patients can be

669 Intestinal Atresia and Stenosis

63.12  Evidence-Based Surgery Title

What is our development progress for the treatment outcome of newborn with intestinal atresia and stenosis in a period of 28 years?

Authors

İbrahim Akkoyun, Derya Erdoğan,1 Yusuf Hakan Çavuşoğlu,1 and Özden Tütün1

Institution

Department of Pediatric Surgery, Dr. Faruk Sükan Maternity and Children Hospital Konya, Ankara, Turkey. Department of Pediatric Surgery, Dr. Sami Ulus Maternity and Children Hospital, Ankara, Turkey

Reference

N Am J Med Sci. 2013 Feb; 5(2): 145–148

Problem

The aim of this study was to examine our series of intestinal atresia and stenosis patients in a period of 28 years in a developing country and to display our progress in treatment and survival rates today.

Intervention

In this study, a total of 141 intestinal atresia and stenosis cases were retrospectively evaluated.

Comparison/control (quality of evidence)

The cases were categorized in two groups as 45 cases before the 1990 (group 1) when it was impossible for total parenteral nutrition (TPN) solutions to be used regularly, without complication and for a long time and 96 cases after 1990 (group 2) when this was possible. While the survival rate before 1990 was 55%, after 1990, it was 94%.

Outcome/ effect

As a result, long-term regular TPN usage significantly improved survival in newborns with intestinal atresia and stenosis in a developing country.

Title

Prognostic factors related to mortality in newborns with jejunoileal atresia

Authors

Bracho-Blanchet E1, González-Chávez A, Dávila-Pérez R, Zalles Vidal C, Fernández-­ Portilla E, Nieto-Zermeño J

Institution

Departamento de Cirugía General, Hospital Infantil de México Federico Gómez, Secretaría de Salud, México, D.F., Mexico

Reference

Cir Cir. 2012 Jul-Aug;80(4):345–351

Problem

To assess the factors related to mortality in neonates with jejunoileal atresia.

Intervention

Case–control nested in a cohort design, comparative study during 10 years, between deceased and survivors analyzing factors related to mortality before surgery, during surgery, and in the postoperative period.

..      Fig. 63.6  Type III b atresia with antenatal volvulus of the “apple peel”

supported for prolonged periods of time while awaiting gastrointestinal function. However, in centers without these resources, patient mortality will be higher and primarily attributable to malnutrition. The judicious use of nasojejunal or gastrostomy trans-anastomotic feeding tubes for enteral feeding may be life saving. 63.10  Prevention

Unfortunately, at present, there are no options for prevention since these anomalies are usually not recognized prior to birth. 63.11  Ethical Issues

In resource-poor regions without recourse to intensive care and parenteral nutrition infants with ultra-short-­ bowel resulting from congenital atresia may have to be managed conservatively. Discussion around parental expectations and center outcomes should be part of the informed consent. Nursing staff and other care givers should also be party to the decision-making process. Withdrawal of treatment which is thought futile is often difficult to institute. If there are choices to be made based on allocation of limited resources, then infants with the potential for good outcomes may be given preference for meager resources. However, it is only the infrequent case of intestinal atresia that develops intestinal failure and with prompt operation and preservation of as much functioning bowel as possible prognosis should be excellent.

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Comparison/ control (quality of evidence)

We analyzed 70 patients in 10 years, and there were 10 deaths (14.2%). None had a prenatal diagnosis. Factors related to mortality were intestinal perforation with a relative risk (RR) of 4.4, peritonitis (RR: 5.6), the need of stomas (RR: 4.9), the presence of sepsis (RR: 4.6), and a residual small bowel length below 1 meter (RR: 7.4).

Outcome/ effect

Delay in diagnosis causes late intervention and increased mortality and results in late transport of the neonate which increases mortality.

Historical significance/comments

It is necessary to spread awareness of this disease in the medical community to improve prenatal detection and in utero transfer to centers able to deal with this condition.

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Key Summary Points 1. Intestinal atresia may occur at any level of the gastrointestinal tract. 2. Small bowel atresia in most cases is due to an antenatal ischemic insult to a segment of intestine. Resorption of the infarcted segment leads to occlusion of the lumen with a varying degree of dilatation of the proximal blind end. 3. A third of infants with intestinal atresia are born prematurely. 4. Differential diagnoses include midgut volvulus, meconium ileus, extensive aganglionosis, and intussusception. 5. Primary operation consists of a generous back resection of the bulbous blind end and an end-to-­ end anastomosis.

6. Outcomes are generally good if sufficient bowel length remains. 7. Stomas should be avoided. 8. Mortality rate depends on birth weight, residual bowel length, the degree of dysmotility, associated anomalies, and septic complications.

References 1. Adams SD, Stanton MP.  Malrotation and intestinal atresias. Early Hum Dev. 2014;90(12):921–5. https://doi.org/10.1016/j. earlhumdev.2014.09.017. 2. Ameh EA, Nmadu PT.  Intestinal atresia and stenosis: a retrospective analysis of presentation, morbidity and mortality in Zaria, Nigeria. West Afr J Med. 2000;19(1):39–42. 3. Chirdan LB, Uba AF, Pam SD. Intestinal atresia: management problems in a developing country. Pediatr Surg Int. 2004;20(11– 12):834–7. https://doi.org/10.1007/s00383-004-1152-4. 4. Ezomike UO, Ekenze SO, Amah CC.  Outcomes of surgi cal management of intestinal atresias. Niger J Clin Pract. 2014;17(4):479–83. https://doi.org/10.4103/1119-3077.134045. 5. Louw JH, Barnard CN.  Congenital intestinal atresia; observations on its origin. Lancet. 1955;269(6899):1065–7. 6. Grosfeld J, et  al. Operative management of intestinal atresia and stenosis based on pathological findings. J Pediatr Surg. 1979;14:368. 7. Millar AJW RH, Cywes S. Intestinal atresia and stenosis. In: Ashcraft, editors. Pediatric surgery. 3rd ed.; Philadelphia: WB Saunders; 2000. pp. 406–24. 8. Wang J, Du L, Cai W, Pan W, Yan W.  Prolonged feeding difficulties after surgical correction of intestinal atresia: a 13-year experience. J Pediatr Surg. 2014;49(11):1593–7. https://doi. org/10.1016/j.jpedsurg.2014.06.010. 9. Nusinovich Y, Revenis M, Torres C.  Long-term outcomes for infants with intestinal atresia studied at Children’s National Medical Center. J Pediatr Gastroenterol Nutr. 2013;57(3):324–9. https://doi.org/10.1097/MPG.0b013e318299fd9f.

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Vitelline Duct Anomalies Bankole S. Rouma and Kokila Lakhoo Contents 64.1

Introduction – 672

64.2

Demographics – 672

64.3

Embryology – 672

64.4

Pathophysiology – 672

64.5

Clinical Presentation – 674

64.6

Diagnosis – 674

64.7

Treatment – 675

64.8

Postoperative Complications – 676

64.9

Evidence-Based Research – 676 References – 677

© Springer Nature Switzerland AG 2020 E.A. Ameh et al. (eds.), Pediatric Surgery, https://doi.org/10.1007/978-3-030-41724-6_64

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64.1  Introduction

64.4  Pathophysiology

Vitelline duct or omphalomesenteric duct anomalies are secondary to the persistence of the embryonic vitelline duct, which normally obliterates by weeks 5–9 of intrauterine life. These anomalies occur in approximately 2% of the population and may remain silent and diagnosed only incidentally, or may result in a variety of intra-­abdominal complications. Although Meckel’s diverticulum is the most common vitelline duct anomaly (. Fig.  64.1g), a patent vitelline duct (. Fig. 64.1a) is the most common symptomatic presentation in developing countries [1].

Vitelline duct malformations comprise a wide spectrum of anatomic structures, depending on the degree of involution of the vitelline duct. The most common anomaly is Meckel’s diverticulum, described as being 60 cm from the ileocecal valve, 2 cm in diameter, 3 cm in length, and not attached to the abdominal wall. Most complications of these abnormalities are related to ectopic tissue (gastric, pancreatic, colonic, endometriosis, or hepatobiliary) [7]. Ectopic gastric tissue usually causes bleeding from ulceration of the adjacent ileal mucosa. The ileal mucosa is not equipped to buffer the acid produced by the ectopic gastric mucosa and, thus, is prone to ulceration. The site of the ulceration is most often at the junction of the normal ileal mucosa and the ectopic gastric mucosa. Some studies have shown a very low colonization rate with Helicobacter pylori in children with ulcerative bleeding of Meckel’s diverticulum [3]. Intestinal obstruction may be caused by a Meckel’s diverticulum attached to the umbilicus by a fibrous cord or by a fibrous cord between the ileum and the umbilicus. This may lead to a volvulus around the fibrous cord. A persistent vitelline artery, an end artery from the superior mesenteric artery, may cause obstruction and volvulus. Bowel obstruction can also occur by intussusception with the diverticulum as a lead point or by herniation or prolapse of the bowel through a patent omphalomesenteric fistula (with a characteristic “ram’s horn” appearance) [5]. Obstruction may be caused by phytobezoar [6, 7]. Like the appendix, a Meckel’s diverticulum can become inflamed when the lumen is obstructed, resulting in decreased mucosal perfusion, tissue acidosis, and bacterial invasion of the wall. This can lead to progressive inflammation, with tissue gangrene and perforation. It is possible that the gastric or pancreatic mucosa contributes to the luminal obstruction, or the gastric mucosa can lead to ileal mucosal ulceration first, which facilitates bacterial invasion. Rarely, foreign bodies and parasites may be trapped within the diverticulum and cause obstruction of the diverticulum as does an enterolith [7, 8]. Diverticular torsion leads to secondary ischemia and inflammatory change [7]. Anomalies of the omphalomesenteric duct can result in umbilical drainage from granulation tissue. Other anomalies include a duct close at the umbilicus covered with skin (. Fig.  64.1b); diverticulum attached to the umbilicus with a fibrous cord (. Fig. 64.1c), Littre’s hernia, and intra-abdominal cystic mass (. Fig. 64.1d, e).

 

 

64.2  Demographics

The most frequent malformation is Meckel’s diverticulum, with an incidence of 2–3% of the population, but it is one of the most unlikely to cause symptoms. About 4% of children with a Meckel’s diverticulum develop symptoms, and more than 60% of those who develop symptoms are younger than 2  years of age [2–5]. The male-to-female complication rate ratio is about 3:1 [3].

64.3  Embryology

During week 3 of gestation, the midgut is open into the yolk sac, which does not grow as rapidly as the rest of the embryo. Subsequently, by week 5, the connection with the yolk sac becomes narrowed and is then termed a yolk stalk, vitelline duct, or omphalomesenteric duct. Normally, the vitelline duct disappears by gestational week 9, just before the midgut returns to the abdomen. Persistence of some portion of the vitelline duct results in a number of congenital anomalies, of which Meckel’s diverticulum is the most common. This anomaly is variable in length and location, but most often, it is observed as a 1–5 cm intestinal diverticulum projecting from the antimesenteric wall of the ileum within 100  cm of the cecum. It possesses all three layers of the intestinal wall and has its own blood supply. The connection in a patent vitelline duct is usually to the ileum, but less commonly may be to the appendix or colon [1]. In other cases, part of the vitelline duct within the abdominal wall persists, forming an open omphalomesenteric fistula, an enterocyst, or a fibrous band connecting the small bowel to the umbilicus [2–7].

 

 

 

673 Vitelline Duct Anomalies

a

b

c

d

e

..      Fig. 64.1  Remnants of the omphalomesenteric duct: a patent vitelline duct; b patent vitelline duct covered by skin; c Meckel’s diverticulum with fibrous cord; d cyst with fibrous cord; e cyst; f fibrous cord; g Meckel’s diverticulum

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Some tumors can be found in ectopic tissues, such as nesidioblastosis in ectopic pancreas tissue of a Meckel’s diverticulum or tumors such as carcinoid, leiomyoma, neurofibroma, and angioma [6–9]. Associated congenital anomalies include cardiac defects, congenital diaphragmatic hernia, duodenal atresia, esophageal atresia, imperforate anus, gastroschisis, malrotation, omphalocele, Hirschsprung’s disease, and Down syndrome.

64.5  Clinical Presentation

The clinical presentation of vitelline duct abnormalities is variable and depends on the configuration of the remnant of the vitelline duct and whether it contains ectopic gastric or pancreatic tissues. In developed countries, the main forms of presentation are hemorrhage in 40–60%, obstruction in 25%, diverticulitis in 10–20%, and umbilical drainage [3–5]. The classic presentation is an older infant or young child with painless rectal bleeding. This usually consists of a large volume of bright red bleeding but can occasionally also present as dark, tarry stools in small amounts. The bleeding is often massive and frequently requires transfusion. Melena may be episodic and usually ceases without treatment; sometimes, the melena is insidious and not appreciated by the family. A young child with hemoglobin-positive stools and a chronic iron deficiency anemia must be investigated for Meckel’s diverticulum. Intestinal obstruction, usually due to intussusception, is the most typical presentation in newborns and infants. The symptoms include crampy abdominal pain, bilious vomiting, currant-jelly stools, and abdominal distention. Intestinal obstruction may also be caused by a volvulus or arterial band. Because the volvulus usually involves the distal small bowel and the obstruction is most often a closed loop, there may be little emesis until late in the course. The sequelae of intestinal ischemia, such as acidosis, peritonitis, and shock, may occur first and can be fatal in infants. Patients with Meckel’s diverticulitis often have symptoms that resemble appendicitis. They are usually older children. Periumbilical pain is the first symptom. They usually do not have the same amount or intensity of vomiting and nausea as do children with appendicitis. On physical examination, their point of maximal tenderness may migrate across the abdomen as the child moves. About the same percentage of patients with diverticulitis will present with perforation. A perforated Meckel’s diverticulum is potentially more serious than a perforated appendix because the former is more difficult to wall off due to its more mobile position. This may explain why perforated diverticulitis is more likely to

result in diffuse peritonitis and pneumoperitoneum detectable on abdominal radiographs. For this reason, it is imperative to search carefully for a perforated Meckel’s diverticulum as the cause of peritonitis when no inflamed appendix is discovered at appendectomy. Other types of symptomatic omphalomesenteric duct malformations can result in umbilical drainage as well. The quantity and character of the drainage may indicate the origin of the lesion. Clear drainage or yellowish drainage signifies a probable urachal anomaly, whereas an omphalomesenteric duct remnant manifests as feculent drainage (. Fig.  64.2). The most common umbilical lesion is an umbilical granuloma, which secretes a mucoid material. If the drainage persists despite cauterization of the presumed granuloma with silver nitrate, or if the drainage is copious, imaging studies are indicated. Prolapse of the ileum into the duct at the anterior abdominal wall presents as a discolored, mucosa-covered mass situated at the umbilicus.  

64.6  Diagnosis

Diagnosis of a symptomatic vitelline duct malformation is dependent on the anatomic configuration and its presentation, signs, and symptoms. History and physical examination are important for the diagnosis. Some abnormalities are evident on physical examination (fecal fistula, prolapse of ileum through a patent duct, and umbilical granulation tissue with a small fistula). A fistulogram may be necessary to identify the part of the intestine involved preoperatively. A complete description of the quality and frequency of the bloody stools is necessary in patients with rectal bleeding. Rectal examination and lower endoscopy are useful to identify other causes of lower bleeding (polyps and rectal tears). The test of choice for a bleeding Meckel’s diverticulum is a technetium-99m pertechnetate isotope scan (Meckel scan), which preferentially concentrates the isotope in ectopic gastric mucosa. The specificity of scintigraphy is 95%, and the sensitivity is 85% [7]. A negative scan result does not, however, exclude a bleeding Meckel’s diverticulum. This scan is not available in most developing countries. Capsule endoscopy has proven to be of diagnostic value in some cases of bleeding Meckel’s diverticulum, but the reports are very few. The best diagnostic test may be a laparotomy to visually look for a Meckel’s diverticulum in children with unexplained rectal bleeding. If obstruction from either intussusception or volvulus is suspected, plain x-rays may reveal dilated bowel loops and multiple air–fluid levels. An air enema or upper gastrointestinal study with small bowel follow-­ through is suggestive. Ultrasonography remains fairly reliable to diagnose intussusception.

675 Vitelline Duct Anomalies

a

b

..      Fig. 64.2  a Patent vitelline duct; b vitellointestinal communication

A sinogram will exclude intestinal communication in umbilical sinuses, and abdominal ultrasonography should localize a cyst [1]. Inflammatory symptoms are similar to those of appendicitis and are diagnosed clinically. 64.7  Treatment

Symptomatic children with omphalomesenteric duct remnants should be resuscitated before intervention. Those with significant hemorrhage should be transfused. Patients with obstructive symptoms should be resuscitated as rapidly as possible to obviate the need for ischemic bowel resection. The incision chosen varies with the symptoms and the age of the patient. Children with feculent umbilical drainage (. Fig.  64.2) or prolapse of the omphalomesenteric duct remnant can be explored by a small infraumbilical incision. Children with Meckel’s diverticulitis or a bleeding Meckel’s diverticulum are operated on by using a transverse appendectomy incision with medial extension if necessary. Patients with suspected intestinal obstruction should be explored through a generous laparotomy incision. An open diverticulectomy includes the following steps: 1. A transverse appendectomy incision or subumbilical incision is made. 2. The cecum and ileum are identified.  

3. The ileum is followed proximally to find Meckel’s diverticulum, approximately 60 cm from the ileocecal valve. 4. The diverticulum with the ileum is delivered into the wound. 5. The diverticulum is excised with the adjacent ileum, and primary ileal end-to-end anastomosis is fashioned. In developed countries, some surgeons use linear staplers applied to the base of the anomaly, allowing complete amputation of the diverticulum without narrowing the lumen of the ileum. When ectopic gastric or pancreatic tissues are present near the base of the diverticulum, or if the base is wide, inflamed, or perforated, resection of the involved ileum is required with an end-to-end anastomosis [2–5, 10]. If perforation has occurred, thorough peritoneal toileting is done after segmental ileal resection. The use of laparoscopy for resection of Meckel’s diverticula has been reported by many authors [11]. Controversy exists about what should be done when a Meckel’s diverticulum is encountered during a laparotomy for unrelated symptoms. The debate focuses on the probability of the Meckel’s diverticulum becoming symptomatic in the future weighed against the possibility of complications associated with resection [2, 4, 5, 7, 10–13]. Lesions with palpable ectopic mucosa (the consistency of gastric or pancreatic tissue differs sharply

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from that of ileal, jejunal, or colonic mucosal lining), a prominent vitelline artery, a fibrous vitelline artery remnant, evidence of inflammation, or a narrow base may all increase the chance of bleeding, obstruction, or diverticulitis and should be resected when encountered. In patients who have abdominal pain, it is prudent to resect a discovered diverticulum or any lesion with attachments to the umbilicus (to prevent ileal volvulus). Some authors suggest that resection of asymptomatic vitelline remnants in early childhood is reasonable at the time of laparotomy for other conditions [10–13]. In developing countries, incidental Meckel’s diverticulum should be removed in children to prevent later complications. If the diverticulum is left in place, it is imperative to alert the patient’s family and the primary care physician about the presence of the lesion and its possible symptoms.

..      Table 64.1 (continued) Comparison/control (quality of evidence)

Systematic review: A total of 244 papers meeting defined criteria were included; there were no prospective or randomized studies. MD prevalence and mortality from autopsy studies, postoperative complications, and outcome of incidentally detected MD were extracted. Population-based data were obtained from national databases on MD as the cause of death and on the number of MD resections performed per year.

Outcome/ effect

The prevalence of MD is 1.2%, and historical mortality of MD was 0.01%. The current mortality from MD is 0.001%. The number of MD resections per year per 100,000 population decreased significantly after the pediatric age range (P 75% of the cases [8, 13, 31– 33, 42]. Unfortunately, not all lesions are amenable to sclerotherapy; as for the surgical treatment, the macrocystic lesions have the best prognosis (see . Fig. 111.5). There is some indication, however, that sclerotherapy of the macrocysts included in the mixed lesions has improved the microcystic component. A multidisciplinary team approach and the combination of sclerotherapy and surgery offer many advantages.  

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J. O. Seyi-Olajide et al.

Key Summary Points

..      Table 111.4 (continued)

1. Lymphangiomas are not common. 2. Cervical location is the most common and important site. 3. Airway obstruction and infection are common complications in cervical lymphangioma, both before and after surgery. 4. Ultrasonography is the minimum evaluation modality and is necessary to categorise and ascertain the extent of the lesion. 5. Surgical excision is effective, particularly in macrocystic malformations, and can be combined with sclerotherapy. 6. Sclerotherapy is more effective in single cysts and macrocystic lesions. 7. Cystic teratoma should be excluded by imaging and cytology if nonoperative management is initially chosen. 8. Morbidity can be high after surgery: complete excision should not be performed if injury to important structures is likely. Sclerotherapy should generally be the first-line treatment. 9. Morbidity and mortality are most common in cervical lymphangiomas and in infants younger than 1 year of age. 10. In infants younger than 1 year of age presenting without complications, surgery should be delayed to minimise operative morbidity and mortality.

Intervention

Surgical excision, sclerotherapy.

Comparison

Two periods of treatment divided arbitrarily into period I (1979–1988, n = 53) and period II (1989–2005, n = 75). Bleomycin was used as sclerosant in period I, and OK-432 was introduced in period II. Sclerotherapy was used as the primary treatment in 64% of patients in period II

Outcome

Effectiveness of sclerotherapy in single cysts, macrocystic, microcystic, and cavernous (mixed) types was 90.9%, 100%, 68%, and 10%, respectively. Seventeen patients who had primary sclerotherapy required surgical excision with good outcome. Primary surgical excision was significantly more successful than sclerotherapy (88.5% versus 64.0%, p 95% with associated anomalies, low birth weight and prematurity contributing to the