A Colour Atlas of Subtotal Thyroidectomy [Reprint 2021 ed.] 9783112417546, 9783112417539

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Subtotal Thyroidectomy

Single Surgical Procedures A Colour Atlas of

Subtotal Thyroidectomy Peter H. Dickinson

DE

Walter de Gruyter • Berlin • New York

1984

5

Peter H. Dickinson MB, BS (Dunelm) MSc (Surgery, Illinois), FRCS (England), FRCS (Edin.); Senior Consultant Surgeon, Royal Victory Infirmacy, Newcastle upon Tyne; Lecturer in Clinical Surgery, The Medical School, University of Newcastle upon Tyne Copyright © Peter H. Dickinson 1983 Original Publishers: Wolfe Medical Publications Ltd., • London Exclusive co-publishers for the Federal Republic of Germany and Austria: Walter de Gruyter & Co., Genthiner Strasse 13, D-1000 Berlin 30.1984. Printed by Royal Smeets Offset b.v., Weert, Netherlands Cover design: Rudolf Hübler General Editor, Wolfe Surgical Atlases: William F.Walker, DSc,ChM, FRCS (Eng.), FRCS (Edin.), FRS (Edin.) CIP-Kurztitelaufnahme

der Deutschen

Bibliothek

Dickinson, Peter H.: A colour atlas of subtotal thyroidectomy / Peter H. Dickinson. Berlin; New York: de Gruyter, 1984. (Single surgical procedures; 5) ISBN 3-11-010015-0 ISBN 3-11-010014-2 (Subskr.-Pr.) NE: GT

All rights reserved. T h e c o n t e n t s of this book, b o t h p h o t o g r a p h i c a n d textual, m a y not be r e p r o d u c e d in any f o r m by print, p h o t o p r i n t , p h o t o t r a n s p a r e n c y , m i c r o f i l m , m i c r o f i c h e o r any o t h e r m e a n s , n o r may it be i n c l u d e d in a n y c o m p u t e r retrieval s y s t e m , w i t h o u t written p e r m i s s i o n of t h e publisher. D i e W i e d e r g a b e v o n G e b r a u c h s n a m e n , W a r e n b e z e i c h n u n g e n u n d d e r g l e i c h e n in d i e s e m Buch berechtigt nicht z u d e r A n n a h m e , d a ß s o l c h e N a m e n o h n e weiteres von j e d e r m a n n b e n u t z t w e r d e n d ü r f e n . V i e l m e h r h a n d e l t es sich h ä u f i g u m gesetzlich g e s c h ü t z t e , e i n g e t r a g e n e W a r e n z e i c h e n , a u c h w e n n sie nicht eigens als s o l c h e g e k e n n z e i c h n e t sind.

Contents Page Introduction

5

Positioning of patient, skin incision, and exposure of thyroid gland

8

Mobilisation of left thyroid lobe

13

Excision of left thyroid lobe

32

Excision of pyramidal lobe and thyroid isthmus

38

Mobilisation of right thyroid lobe

40

Excision of right thyroid lobe

49

Suction drainage and wound closure

56

Postoperative management

60

Index

5

Introduction Subtotal thyroidectomy is the standard operative procedure in the surgical treatment of thyrotoxicosis. Medical treatment of thyrotoxicosis may be by drug therapy or radioiodine. The choice of treatment, medical or surgical, will vary with the individual patient, the doctor and the clinical circumstances. This Atlas is concerned solely with the operation of subtotal thyroidectomy for thyrotoxicosis. Nevertheless, mention must be made of drug therapy because it has an essential role to play in the preparation of the patient for surgery; no patient is operated upon while still toxic, but is first rendered euthyroid by an antithyroid drug such as carbimazole. The diagnosis of thyrotoxicosis is made on clinical grounds and confirmed by laboratory investigations, which may also help to determine the cause of the hyperthyroidism. Commonly employed tests are measurement of the level of thyroid hormones (T4 and T3) in the blood which have now replaced the in vivo thyroid uptake of isotopes of iodine or pertechnetate. Thyroid isotope scanning using m Tc or 123 I, can help to distinguish between a diffuse and a nodular goitre. In most cases of Graves' disease autoantibodies to thyroid components are present and are determined by standard immunological investigation. Once the diagnosis of thyrotoxicosis has been established the aim of treatment is to reduce the level of thyroid hormone in the blood. This is done initially with one of the antithyroid drugs. Carbimazole is commonly used in the UK (45 mg daily in divided dosage). The patient usually becomes euthyroid in four to six

6

weeks, the clinical improvement being confirmed by estimation of the blood level of T4 and TSH. When the patient is euthyroid the drug dose is reduced to a maintenance level (approximately half the initial dosage) unless the patient has been chosen for surgical treatment, when the initial dose is maintained up to the time of operation. There is the possibility that during drug therapy the thyroid gland will become larger and more vascular, making surgery more difficult. The likelihood of this happening may be reduced by the administration of thyroxine (100-200mcg/day) for at least three weeks before operation. All drugs are discontinued the day before operation. Some clinicians now favour the use of propanalol as the sole therapy before thyroidectomy. Surgical treatment is designed to render permanent the reduction of thyroid hormone in the blood achieved by drug therapy. The basis of the operation of subtotal thyroidectomy is to remove sufficient thyroid tissue to make this possible. A much discussed problem is how much gland should be removed or, alternatively, how large or small should the gland remnants be. The amount of thyroid tissue which is left behind will obviously be governed to some extent by the original size of the gland and the quality of the remaining tissue; some thyroid glands may contain degenerative nodules or be affected by autoimmune thyroiditis, remnants of such glands will need to be larger. The size of the remnants in relation to the incidence of postoperative hypothyroidism or hyperthyroidism has, however, been shown not to be critical.

The method of subtotal thyroidectomy to be described in this Atlas is the one used routinely by the author. Obviously, variations in technique are used by individual thyroid surgeons. For example, the question of whether or not the infrahyoid muscles should be divided is much discussed; the author prefers not to divide them routinely; other surgeons believe they should always be divided, particularly to provide better access to the posterolateral areas of the thyroid lobes. In over 1,000 thyroidectomies, however, the author has found division of the strap muscles to be necessary in only a few; but when the surgeon is inexperienced and the goitre large it may be wiser to divide the muscles until more experience is gained. The author prefers, if possible, to identify the recurrent laryngeal nerves and the parathyroid glands. The recurrent laryngeal nerves are usually

easy to identify either by sight or feel, but the parathyroid glands present greater difficulty because they are variable in number, position and colour and they may have a covering of fat. Usually they are seen as small brown/yellow structures, the upper lying on the posterolateral aspect of the upper part of the thyroid and the lower near the branches of the inferior thyroid artery as they enter the thyroid gland. The normal brown/yellow colour is easily altered by even gentle handling and they may then be seen as darkred or plum-coloured structures. When the parathyroid glands are not found quickly there is no need to go to extreme lengths to identify them, because they can be damaged easily by mobilisation. If the parathyroid glands are not identified early the search should be abandoned; the same applies to the recurrent laryngeal nerves.

7

Positioning of patient, skin incision, and exposure of thyroid gland

1 Position of patient. The patient is placed on the operating table with the neck well extended. This may be achieved by the two-pillow technique. The two pillows are stepped as shown, with the shoulders positioned where the two pillows overlap. The head rests comfortably on the single pillow above the overlap.

8

2 Towel application. Towels are applied in rectangular fashion around the operation field and held in position by towel clips. A plastic adhesive membrane (Op-Site) is then placed on the skin and over the towel edges.

3 Skin incision siting. The siting of the skin incision is important; a badly positioned scar will be unsightly. The line of the skin incision is marked out by a thread which indents the skin. The assistant places one index finger on the point of the chin and the other on the suprasternal notch to assist accurate positioning of the thread.

4 Ensuring a horizontal incision line. The resulting transverse indentation is shown and its position is checked by the 'rule of thumb'; the distal phalanx of the operator's thumb measures the distance of t'.e incision line from the clavicle on each side of the neck. Equal measurements ensure that the incision will be horizontal.

9

5 Deepening skin incision. The skin incision is deepened through the superficial fascia and platysma muscle. Upper and lower flaps of skin, fascia and platysma muscle are then raised from the underlying strap muscles.

10

6 Raising skin-flaps. The flaps may be fashioned by blunt dissection using a gauze mop.

7 Raising skin-flaps. The skin-flaps may be also raised by knife dissection. Usually a combination of blunt dissection and knife dissection techniques are used. Small bleeding points are sealed by diathermy. Larger vessels are ligated. Throughout the operation the author uses nonabsorbable material for ligatures; some surgeons prefer catgut.

8 Holding back flaps. The flaps are held back by a single Sloane's spring retractor,

11

9 Separation of strap muscles. A vertical incision is m a d e between the strap muscles in the midline.

12

10 Exposure of isthmus of thyroid gland. T h e medial edges of the strap muscles a r e h e r e held apart revealing the isthmus of the thyroid gland.

Mobilisation of left thyroid lobe 11 Choice of lobe. The areolar tissue deep to the strap muscles is separated to open up the plane between the strap muscles and the capsule of the left lobe of the thyroid gland. The choice of which thyroid lobe to expose first is an individual one, as is the side on which the surgeon stands. The author's preference is to stand on the side opposite to the lobe being mobilised. All photographs in this Atlas are taken from the same side of the patient as the surgeon is standing, unless otherwise stated.

11

13

12 Middle thyroid vein. T h e left thyroid lobe is grasped in Lahey gland-holding forceps and pulled medially. T h e middle thyroid vein (which can vary considerably in size and position) is sought. It is shown h e r e held u p by dissecting f o r c e p s in its classic position running laterally f r o m the middle of the thyroid lobe to cross t h e c o m m o n carotid artery and e n t e r the internal jugular vein.

14

12

13 Division and ligation of middle thyroid vein. The middle thyroid vein is secured between two artery forceps, divided and ligated. Access to the posterolateral aspect of the lobe is now possible.

13

15

14 Inferior thyroid artery. The inferior thyroid artery, which can also vary in its position, is sought well away from the gland near to its point of emergence from deep to the common carotid artery. The inferior thyroid artery is here held up (but not secured) by artery forceps; the common carotid artery is the lighter coloured structure just beneath the upper retractor.

16

15 Temporary clamping of inferior thyroid artery. T h e inferior thyroid artery may be ligated in continuity or c l a m p e d temporarily by a bulldog clamp as shown here. T e m p o r a r y clamping allows a normal blood supply to be restored to the parathyroid glands w h e n the clamp is r e m o v e d .

16 Upper pole exposed. T h e u p p e r pole of the left thyroid lobe, containing the superior thyroid artery and vein, is now exposed. A finger is gently separating areolar tissue and the strap muscles away f r o m the thyroid gland. T h e Dunhill d o u b l e - h o o k e d retractor u n d e r t h e strap muscles helps to provide a clearer view of the u p p e r pole.

18

16

17 Scissor dissection of fascia. Fascia binding the upper pole to the trachea may need to be divided by scissor dissection before the upper pole can be fully mobilised preparatory to ligation and division of the superior thyroid vessels.

19

18 Upper pole grasped. The upper pole is being grasped between the operator's finger and thumb and drawn downwards.

20

18

19 Use of thyroid dissector. A Kocher's thyroid dissector has been passed deep to the upper pole.

20 Dissection and clamping of upper pole. T h r e e artery forceps are now placed across the u p p e r pole vessels. T h e lowest artery forceps may include thyroid tissue. T h e dissection of the u p p e r pole should be kept close to the thyroid gland so that the possibility of injury to the external laryngeal nerve is r e d u c e d ; m i n o r voice changes a f t e r o p e r a t i o n can be caused by d a m a g e to this nerve.

22

21 Division of vessels. The vessels are divided between the lower and upper two artery forceps. It is a wise precaution to place two artery forceps above, as the vessels can slip out of one pair of artery forceps and cause troublesome bleeding. If this does happen, finger pressure applied through the skin above the wound will control the bleeding and enable the cut ends of the vessels to be picked up.

23

22 Applying ligatures. T w o ligatures are applied to the proximal cut ends of the vessels. H e r e the second of the two ligatures is being tied. T h e distal cut ends of the vessels are then tied on the thyroid gland.

24

23 Posterolateral structures exposed. The left thyroid lobe is now pulled medially to expose the structures lying posterolaterally. The bulldog clamp remains on the inferior thyroid artery; the dissecting forceps point to the recurrent laryngeal nerve lying in the groove between the trachea and the oesophagus. Note its relationship to the branching inferior thyroid artery. When not seen, the nerve may be identified by gently rolling it against the trachea, when it can be felt as a fine cord.

23

25

24 Parathyroid glands. T h e dissecting forceps point to the u p p e r left p a r a t h y r o i d gland. T h e lower left parathyroid gland is lying d e e p to fascia just anterior to the recurrent laryngeal nerve, w h e r e the inferior thyroid artery is beginning to b r a n c h ; it is difficult to identify in this p h o t o g r a p h . N o a t t e m p t is m a d e to mobilise the p a r a t h y r o i d glands unless they lie on a part of t h e thyroid gland which is to be removed.

26

25 Inferior thyroid veins. The lower pole of the left thyroid lobe is now pulled upwards to demonstrate the inferior thyroid veins (the lower pole also contains fatty tissue, an occasional artery and, in some younger patients, the upper part of the thymus gland). Here some of the veins and fatty tissue are held in artery forceps ready for ligation. The main inferior thyroid veins are seen lying on the trachea deep to the artery forceps.

26 Divided and ligated lower pole vessels. The lower pole vessels have now been divided and ligated; two rings of the trachea can be seen at the tip of the Kocher's dissector.

28

27 Trachea identification. The tip of the Kocher's dissector is now pointing to the trachea above the left thyroid lobe. It is obscured by the pyramidal lobe which will be removed later. The identification of the trachea above and below the left thyroid lobe is a necessary preliminary to the next step in the operation.

28 Kocher's dissector passed deep to thyroid isthmus. T h e K o c h e r ' s dissector is now passed d e e p t o the isthmus of the thyroid gland and in f r o n t of the trachea as the left thyroid lobe is pulled f o r w a r d s and medially. A r t e r y forceps are to be applied to the thyroid capsule, but b e f o r e this is d o n e , t h e position of the parathyroid glands and the recurrent laryngeal nerve should be checked again.

30

28 I

29 Checking position of parathyroid glands and recurrent laryngeal nerve. In this view, with the K o c h e r ' s dissector in position and the gland pulled medially, the relationship of the dissector to the recurrent laryngeal nerve and parathyroid glands is shown. T h e r e c u r r e n t laryngeal nerve is seen crossing the inferior thyroid artery well behind the K o c h e r ' s dissector and t h e two parathyroid glands are in line with the lateral margin of the K o c h e r ' s dissector, so that artery f o r c e p s placed on the thyroid capsule just anterior to the guide will avoid injury t o these structures.

Excision of left thyroid lobe 30 Positioning of artery forceps on posterolateral capsule. A row of artery forceps art now placed on the capsule of the posterolateral part of the thyroid lobe, their precise positioning will d e p e n d u p o n how much of the thyroid lobe is to be r e m o v e d . Division of the thyroid lobe by knife dissection can now begin.

32

31 Knife dissection of left lobe and control of bleeding points. Most of the bleeding points are in or near the thyroid capsule and are controlled by the artery forceps which have been already placed. Bleeding points within the substance of the gland are picked up by artery forceps and ligated or coagulated as the dissection proceeds.

31

33

32 Artery forceps on posteromedial capsule. When the capsule of the posteromedial part of the thyroid lobe is reached, it is picked up in a series of artery forceps in a similar m a n n e r to those placed on the posterolateral thyroid capsule. H e r e the posteromedial capsule is being divided; when division is complete, the Kocher's dissector is removed.

34

32

33 Subtotal removal of left thyroid lobe is complete with artery forceps in position, awaiting ligature. All the artery forceps are in position. The posteromedial capsule has been divided. Ligatures are now applied around each artery forceps in turn.

33

35

34 Fixation of left lobe remnant. T h e r e m n a n t of the left thyroid lobe, f r e e f r o m bleeding, is now ready to be stitched to the side of the t r a c h e a by several interrupted sutures of 2/0 chromic catgut placed b e t w e e n the posterolateral thyroid capsule and the connective tissue covering the side of the trachea. T h e first of these sutures is being tied.

36

35 Care of laryngeal nerve and parathyroid glands. With the catgut sutures tied, the left thyroid lobe remnant lies snugly against the side of the trachea; any oozing from the cut surface is thus controlled. Care must be taken to avoid including the recurrent laryngeal nerve and the parathyroid glands in these sutures. The bulldog clamp can now be removed from the inferior thyroid artery.

35

37

Excision of pyramidal lobe and thyroid isthmus 36 Dissection of pyramidal lobe. When a pyramidal lobe is present it should be dissected free and removed with the main specimen. It is shown being lifted up by artery forceps. It has a rich blood supply and several vessels have usually to be ligated and divided, before it is freed.

38

36

37 Excision of pyramidal lobe and isthmus. Finally, the upper extremity of the pyramidal lobe is divided between two artery forceps. Both cut ends are ligated. This completes the left side of the operation. The pyramidal lobe remains attached to the thyroid isthmus, which is lifted off the trachea by blunt or sharp dissection.

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39

Mobilisation of right thyroid lobe 38 Right strap muscles retraction. The surgeon is now standing on the left side of the patient for the next stage of the operation, which is mobilisation of the right thyroid lobe. The strap muscles are being retracted and separated from the underlying thyroid lobe. This may be done by finger or scissor dissection depending upon the consistency of this tissue, which varies from individual to individual.

40

38

39 Middle thyroid vein. The middle thyroid vein is seen running across the common carotid artery from the posterolateral part of the thyroid gland. It will be divided between ligatures to provide access to the side and back of the right thyroid lobe.

40 Inferior thyroid artery. The inferior thyroid artery is mobilised as it emerges from deep to the common carotid artery. It will be occluded temporarily with a bulldog clamp. The recurrent laryngeal nerve is seen crossing the inferior thyroid artery nearer to the thyroid gland.

42

41 Mobilisation of right upper pole. The right upper pole is now mobilised and a Kocher's dissector passed deep to it. The upper pole generally extends higher on the right than on the left side and a tongue of thyroid gland often passes medially deep to the pharynx. This may make mobilisation of the right upper pole a little more difficult than on the left side. This 'tongue' is not clearly shown here but it can be seen on the operation specimen (58).

42 Superior thyroid artery. In some instances it may be more expedient to take the upper pole vessels in two 'bites' rather than in a single manoeuvre. Here the superior thyroid artery is secured between two artery forceps and divided as it lies on the upper pole.

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43 Remaining upper pole vessels secured. The remaining upper pole vessels have been secured in three artery forceps and are being divided by scissors between the lower and upper two artery forceps. Ligatures are then applied.

43

45

44 Inferior thyroid veins. This view is taken from below the wound and shows the right thyroid lobe being drawn upwards. The leash of inferior thyroid veins lie between the tip of the artery forceps and the retractor. They are secured in two artery forceps, divided and ligated.

46

45 Posteromedial aspect of lobe exposed. The right thyroid lobe is being lifted forwards and laterally to expose the posteromedial aspect of the lobe where it is attached to the side of the trachea by fairly dense fascia. This fascia is being divided by the scalpel. This dissection must be limited to a depth of 1mm or 2 mm only. Small vessels are secured on the capsule of the thyroid gland with artery forceps. If this dissection is made too deeply, troublesome bleeding may occur and the recurrent nerve will be in danger of injury, particularly in the upper more anterior part of its course just before it enters the larynx, behind the inferior cornu of the thyroid cartilage.

45

47

46 Posterolateral structures exposed. T h e right thyroid lobe is now pulled f o r w a r d s and medially. B e f o r e placing a row of artery forceps on the posterolateral capsule of the thyroid lobe, p r e p a r a t o r y to dividing it, an a t t e m p t should be m a d e to locate the recurrent laryngeal nerve and the p a r a t h y r o i d glands. T h e bulldog clamp is on the inferior thyroid artery; the tip of the dissecting forceps is pointing to the recurrent laryngeal nerve, which is running obliquely forwards t o e n t e r the larynx. T h e parathyroid glands have not b e e n clearly identified; however, so long as it can be seen that they are not lying on that part of the thyroid lobe which is to be r e m o v e d , it is safe to p r o c e e d .

48

Excision ofrightthyroid lobe

49

48 Artery forceps on posteromedial thyroid capsule. Similarly, a row of artery forceps are placed along the posteromedial thyroid capsule. Note that the posterior part of the lobe is still adherent to the trachea. The recurrent laryngeal nerve is not in danger, so long as the artery forceps are placed on the thyroid capsule and not on the trachea.

50

48 |

49 Knife dissection of right lobe. The desired amount of thyroid tissue is now removed by scalpel dissection. Bleeding points within the thyroid substance are picked up in artery forceps for ligation or coagulation. The dissection proceeds as far as the posteromedial thyroid capsule.

49

51

50 Subtotal removal of right thyroid lobe. With the thyroid gland pulled laterally, t h e posteromedial thyroid capsule is finally divided t o c o m p l e t e the subtotal removal of the right thyroid lobe.

52

51 Artery forceps on bleeding points. Removal of the desired a m o u n t of the right thyroid lobe is c o m p l e t e and the r e m n a n t is seen with t h e artery forceps still in position awaiting ligation of the vessels within t h e m .

52 Remnant of right lobe awaiting fixation to trachea. The vessels have been ligated; the remnant is free from bleeding and is ready to be sutured to the side of the trachea with interrupted sutures of 2/0 chromic catgut.

54

53 Both lobe remnants sutured to trachea. In this view, taken from below the wound, both thyroid lobe remnants are shown sutured to the sides of the trachea. Check that the bulldog clamps have been removed from each inferior thyroid artery.

53

55

Suction drainage and wound closure 54 Suction drain placement. A Redivac suction drain is placed adjacent to each thyroid lobe remnant and brought through the muscles and the skin below the edge of the wound on the opposite side. Each drainage tube is attached to a separate suction bottle.

56

54

55 Approximation of strap muscles. T h e strap muscles a r e a p p r o x i m a t e d in the midline by a continuous suture of 2/0 catgut placed through the fascia covering the muscles. Care must be t a k e n to avoid the anterior jugular veins.

55

57

56 Control of bleeding points. Remaining bleeding points in the subcutaneous tissues are ligated or coagulated before the skin is closed. A separate suture for the platysma muscle is not necessary.

56

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57 Approximation of skin edges. The skin edges are approximated with metal clips or sutures.

58 Operation specimen. The operation specimen shows both thyroid lobes joined by the isthmus and the pyramidal lobe. The higher right upper pole with its 'tongue' which lay behind the pharynx is clearly seen.

59

Postoperative management Postoperative recovery is usually straightforward a f t e r thyroidectomy. T h e suction drains are r e m o v e d along with half of the skin clips or sutures on t h e second postoperative day. T h e remaining skin clips are r e m o v e d on the third postoperative day. T h e patient is discharged h o m e on t h e f o u r t h or fifth day a f t e r o p e r a t i o n .

Postoperative thyroid crisis has almost d i s a p p e a r e d as a clinical entity since t h e introduction of antithyroid d r u g p r e p a r a t i o n . If it should occur, sodium iodide, carbimazole, p r o p r a n o l o l and hydrocortisone are drugs which m a y be used. Body cooling can be helpful in severe hyperpyrexia.

Early postoperative complications

Late postoperative complications

S o m e d e g r e e of bleeding a f t e r o p e r a t i o n is usual, requiring routine use of w o u n d drainage. O n average about 50ml of blood drains during the first 24 hours. Serious h a e m o r r h a g e may occur either f r o m a slipped ligature or an overlooked divided vein, the most d a n g e r o u s effect of which is pressure on t h e trachea by the accumulating blood. W h e n respiratory obstruction caused by h a e m o r r h a g e does occur, the w o u n d should be r e o p e n e d immediately in the ward. T h e patient is then r e t u r n e d to t h e operating t h e a t r e w h e r e the blood is r e m o v e d and t h e bleeding point secured and the w o u n d re-sutured. Respiratory obstruction m a y also be caused by tracheal collapse, the accumulation of mucus in the t r a c h e a , laryngeal o e d e m a or vocal cord paralysis or a combination of these causes. Simple tracheal suction may suffice to relieve the obstruction but bronchoscopy a n d , occasionally, a t e m p o r a r y tracheostomy m a y be necessary. Postoperative tetany caused by removal or d a m a g e to the parathyroid glands is rare. W h e n it does occur it can be controlled by t h e administration of calcium orally or intravenously (calcium gluconate), d e p e n d i n g u p o n the severity of the clinical situation.

L a t e postoperative complications of subtotal thyroidectomy are hypothyroidism, hyperthyroidism, chronic calcium deficiency and voice changes. Hypothyroidism occurs in a b o u t 15 per cent of cases, it may be transient in some but in o t h e r s it is p e r m a n e n t and will require t r e a t m e n t with thyroxine for life. Hyperthyroidism is less c o m m o n , occurring in a b o u t 5 per cent of cases. T h e s e patients should be treated with antithyroid drugs or radioiodine. A second o p e r a t i o n should be avoided because of the technical p r o b l e m s posed by distorted a n a t o m y ; p a r a t h y r o i d gland and r e c u r r e n t laryngeal nerve injury being much m o r e likely. P e r m a n e n t hypoparathyroidism is best t r e a t e d by the administration of calcium alone; long-term administration of Vitamin D may result in intoxication. S o m e impairment of the voice may occur i n d e p e n d e n t l y of recurrent laryngeal nerve d a m a g e , but is rarely of serious c o n s e q u e n c e and generally the voice returns to n o r m a l . In a few instances these voice changes (which may be caused by external laryngeal nerve injury) are p e r m a n e n t , but m i n o r .

60

Index Figures in medium type refer to page numbers; those in bold refer to figure and caption numbers.

A Antibodies, thyroid, 6 Anti-thyroid drugs — preoperative treatment with, 6 — in treatment of postoperative hypothyroidism, 60 Arteries, inferior thyroid — relationship with lower parathyroid gland, 7 Artery — left common carotid — relationship to middle thyroid vein, 12 — right common carotid — relationship to middle thyroid vein, 39 — left inferior thyroid — identification of, 14 — relationship to common carotid artery, 14 — temporary clamping of, 15 — bulldog c l a m p o n , 2 3 — relationship to recurrent laryngeal nerve, 2 3 , 2 9 — relationship to Kocher's dissector, 29 — left superiorthyroid, 16 — right inferior thyroid — mobilisation of, 40 — temporary clamping of, 40 — relationship to recurrent laryngeal nerve, 40 — right superior thyroid — secured on upper pole, 42

B Bleeding points — control of, 31 — subcutaneous — diathermy of, 7 — ligation of, 7 — final control of before skin closure, 56 — during division of left thyroid lobe — control by ligation or coagulation, 31 Bleeding, postoperative — causes of, 60 — treatment of, 60 — respiratory obstruction due to, 60

Body cooling - in treatment of postoperative hyperpyrexia, 60 Bronchoscopy - in treatment of postoperative respiratory obstruction, 60 Bulldog artery clamp - on left inferior thyroid artery, 15 - on right inferior thyroid artery, 4 0 , 4 6 - removal of, 35, 53

C Calcium - postoperative treatment with for postoperative tetany, 60 for permanent hypoparathyroidism, 60 Carbimazole - in treatment of thyrotoxicosis, 6 - in treatment of postoperative thyrotoxicosis, 60 Complications, postoperative - early, 60 - late,60

D Drain, suction - placement of, 54 - postoperative removal of, 60 Drugs - anti-thyroid, 6 - carbimazole,6,60 - radoiodine, 6 - in postoperative thyroid crisis hydrocortisone, 60 propranolol, 6 , 6 0 sodium iodide, 60 thyroxine, 6 Dunhill retractor - u s e o f t o e x p o s e u p p e r p o l e , 16

E External laryngeal nerve (see under Nerves) 61

F

M

F a s c i a , superficial, 5 G

M a n a g e m e n t of patient — preoperative,6 — postoperative,60

Graves'disease (see under T h y r o t o x i c o s i s )

N

H H o r m o n e s , thyroid (see under T h y r o i d ) Hydrocortisone - in treatment of p o s t o p e r a t i v e thyroid crisis, 60 Hyperthyroidism, postoperative, 6 - incidence and treatment o f , 60 Hypoparathyroidism, permanent postoperative - treatment of, 60 Hypothyroidism, postoperative, 6 - incidence and treatment o f , 60 I Inferior thyroid artery - t e m p o r a r y clamping o f , 15 Infrahyoid muscles ( s e e under S t r a p ) Isthmus ( s e e under T h y r o i d )

K K o c h e r ' s thyroid dissector - d e e p to left u p p e r p o l e , 19 - d e e p to thyroid isthmus, 28 - pointing to t r a c h e a , 26, 27 - p a s s e d d e e p to thyroid i s t h m u s ; 28 in position, 29 relationship to recurrent laryngeal nerve, 29 relationship to parathyroid g l a n d s , 29 - d e e p to right upper p o l e , 41

L L a h e y gland holding f o r c e p s , 12 Larynx - recurrent laryngeal nerve e n t e r s , 45 - o e d e m a o f , 60 Ligatures - applying o f , 22

62

N e r v e , external laryngeal — avoiding injury to, 20 — p o s t o p e r a t i v e voice c h a n g e s d u e to injury to, 2 0 , 6 0 — left recurrent laryngeal — lying between trachea and o e s o p h a g u s , 23 — relationship to inferior thyroid artery, 2 3 , 2 9 — relationship to lower left parathyroid g l a n d , 24 — relationship to K o c h e r ' s dissector, 29 — care in avoiding during fixation of left lobe r e m n a n t , 35 — right recurrent laryngeal — relationship to inferior thyroid artery, 40 — relationship to p o s t e r o m e d i a l part of thyroid l o b e , 45 — entering larynx, 4 5 — relationship to p o s t e r o l a t e r a l part of thyroid l o b e , 46 N e r v e s , recurrent laryngeal — identification at o p e r a t i o n , 7 — p o s t o p e r a t i v e voice changes d u e to injury to, 60 O O e d e m a of larynx (see under Larynx) Oesophagus — relationship of left recurrent laryngeal nerve to, 23 Op-site, 2

P Parathyroid glands — checking position o f , 29 — d a m a g e to at o p e r a t i o n , 7 — identification at o p e r a t i o n , 7 — c a u s e of p o s t o p e r a t i v e tetany, 60 — maintaining b l o o d supply to, 14 -left — position of u p p e r , 24 — relationship to recurrent laryngeal n e r v e , 24 — checking position o f , 28 — relationship to K o c h e r ' s d i s s e c t o r , 29 — care to avoid when fixing lobe r e m n a n t , 3 5 — right — no attempt to locate, 4 6

Pharynx - relationship to right upper pole, 41,58 Platysma muscle, 5,56 Position of patient - extension of neck, 1 - shoulders, 1 - two-pillow technique, 1 Propranolol - preoperative preparation with, 6 - in treatment of postoperative thyroid crisis, 60 Pyramidal lobe - obscuring trachea, 27 - dissection of, 36 - blood supply of, 36 - excision of, 37 - on operation specimen, 58 R Radioiodine (see under Drugs) Recurrent laryngeal nerves (see under Nerves) Redivac (see under Drain) Remnant, thyroid (see under Thyroid) Remnant, size of - relationship to postoperative hypothyroidism, 6 - relationship to postoperative hyperthyroidism, 6 Respiratory obstruction, postoperative - causes of, 60 - treatment of, 60 Retractor (see Dunhill's and Sloane's) Rule of thumb - use in checking position of skin incision, 4 S Skin incision - siting of, 3 - use of thread to mark out, 3 - rule of thumb to check, 4 - deepening of, 5 Skin clips - skin closure with, 57 - postoperative removal of, 60 Skin flaps - raising of, 5 , 6

- knife dissection of, 7 - blunt dissection of, 7 - retraction of, 8,16 Sloane's spring retractor, 8 Sodium iodide (see under Thyroid crisis) Strap muscles - exposure of, 5 - separation of, 9,38 - held apart, 10 - approximation with catgut, 55 Subtotal thyroidectomy - individual technique of, 7 - division of strap muscles in, 7 T Tetany, postoperative - causes of, 60 - treatment of, 60 - calcium in, 60 Thymus gland, 25 Thyroid cartilage - inferior cornu of, 45 - relationship to recurrent laryngeal nerve, 45 Thyroid crisis, postoperative - treatment of, 60 Thyroid gland - vascularity of, control by thyroxine, 6 - remnant size, 6 - degenerative nodules of, 6 - autoimmune thyroiditis in, 6 Thyroid hormones - measurement of blood level in thyrotoxicosis, 6 - reduction in blood level of, 6 Thyroid isthmus - exposure of, 9 - Kocher's dissector deep to, 28 - Kocher's dissector in position under, 29 - lifted off trachea,37 - on operation specimen, 58 Thyroid lobe, left - mobilisation of, 11-29 - posterolateral aspect of, 13 - posterolateral structures exposed, 23 - lower pole vessels ligated, 26 - knife division of, 30 - posterolateral capsule of, 63

— a r t e r y f o r c e p s o n , 30 — posteromedial capsule — a r t e r y f o r c e p s o n , 32 — division o f , 35 — remnant — stitched t o t r a c h e a , 34 — c a r e of r e c u r r e n t laryngeal n e r v e a n d p a r a t h y r o i d g l a n d s d u r i n g fixation o f , 35 — c o n t r o l of o o z i n g f r o m , 35 — subtotal removal of, 33 — upper pole of, 1 6 , 1 7 , 1 8 — K o c h e r ' s d i s s e c t o r a n d , 19 — a r t e r y f o r c e p s o n , 20 — division of b e t w e e n f o r c e p s , 21 — control o f b l e e d i n g f r o m , 2 1 — ligation of vessels in, 22 T h y r o i d l o b e , right — k n i f e dissection o f . 49 — mobilisation of, 38-48 — posterolateral aspect of, — s t r u c t u r e s e x p o s e d , 46 — r e l a t i o n s h i p t o r e c u r r e n t laryngeal n e r v e , 46 — posterolateral capsule of, — artcryforcepson,47 — posteromedial aspect of, — exposure of, 45 — attachment to trachea, 45 — r e l a t i o n s h i p t o r e c u r r e n t laryngeal n e r v e , 45 — posteromedial capsule of, — a r t e r y f o r c e p s o n , 48 — d i v i d e d , 50 — r e m n a n t a w a i t i n g fixation t o t r a c h e a , 52 — s u b t o t a l excision c o m p l e t e , 51 — upperpole, — m o b i l i s a t i o n o f , 41 — Kocher'sdissectordeepto,41 — r e l a t i o n s h i p with p h a r y n x , 41 — vessels l i g a t c d . 42 Thyrotoxicosis — a n t i b o d i e s , t h y r o i d in, 6 — diagnosis of, 6 — drug therapy in,6 — f u n c t i o n tests, t h y r o i d in, 6 — h o r m o n e s , t h y r o i d b l o o d level in, 6 — i m m u n o l o g i c a l i n v e s t i g a t i o n s in, 6 — i s o t o p e s c a n n i n g , t h y r o i d , in, 6 — l a b o r a t o r y i n v e s t i g a t i o n s in, 6 64

- medical treatment of, 6 - postoperative (see under Hyperthyroidism) - preparation for surgery for, 6 - radioiodinefor,6 - surgical t r e a t m e n t o f , 6 Thyroxine (T4) - b l o o d level m e a s u r e m e n t o f , 6 - preoperative administration of, 6 - in t r e a t m e n t of p o s t o p e r a t i v e h y p o t h y r o i d i s m , 60 Towel application, 2 Trachea - r e l a t i o n s h i p of left r e c u r r e n t l a r y n g e a l n e r v e , 2 3 - left i n f e r i o r t h y r o i d veins lying o n , 25 - i d e n t i f i c a t i o n o f , 26, 27 - fixation of l o b e r e m n a n t t o , 34 - right l o b e r e m n a n t , a w a i t i n g fixation to, 52 - both lobe r e m n a n t s sutured to, 53 - postoperative obstruction of, collapse o f , 60 m u c u s a c c u m u l a t i o n in, 60 t r a c h e a l s u c t i o n f o r , 60 b r o n c h o s o p y f o r , 60 t e m p o r a r y t r a c h e o s t o m y f o r , 60 Tracheostomy, temporary - f o r t r a c h e a l o b s t r u c t i o n , 60 V V e i n , left m i d d l e t h y r o i d - crossing c o m m o n c a r o t i d a r t e r y , 12 - division a n d l i g a t u r e , 13 - left s u p e r i o r t h y r o i d , 16 - right m i d d l e t h y r o i d division o f , 39 V e i n s , left i n f e r i o r t h y r o i d - a w a i t i n g ligation, 25 - right a n t e r i o r j u g u l a r ligation a n d division o f , 44 - anterior jugular a v o i d i n g i n j u r y t o d u r i n g w o u n d c l o s u r e , 55 V e s s e l s , left s u p e r i o r t h y r o i d - ligation a n d division o f , 17 Vitamin D - in t r e a t m e n t of p o s t o p e r a t i v e h y p o p a r a t h y r o i d i s m , 60 Vocal cords - paralysis o f , 60 Voice changes - postoperative, 20,60