BARRACLOUGH A N D REEVE
COMPLICATIONS OF THYROIDECTOMY REFERENCES BELL, G. and SHORT,D. W. (1g72), Brit. J. Surg., 59: 429.
FOLKOW,B. and NEIL, E. (1971), “Circulation”, Oxford University Press, New York, London, Toronto. GOODMAN,A. H. and LI~TLE, J. M. (I971), Mod. Med. Aust., 13: 81. LEE, B. Y . and TRAINOR, F. S. (IQ73), “Peripheral Vascular Surgery : Hanodynamics of Arterial
Pulsatile Blood Flow”, Appleton-Century-Crofts, New York. LITTLE,J. M., SHEIL,A. G. R., LOEWENTHAL, J. and GOODMAN, A. H. (1968), Lancet, 2: 648. MUNKO, R. (1973), personal communication. WEALE, F. E. (1969). Ann. Surg., 169: 489. WESOLOWSKI, S. A., MARTINEZ,A,, DOMINGO, R. T., FRIES, C. L., SCHAEFFER, H. L., SAWYER, P. N., GILLIE,E. and MCMAHON, J. D. (1966), Surgery, 60: 288.
Postoperative Complications of Thyroidectomy : A Comparison of Two Series at an Interval of Ten Years’ B. H. BARRACLOUGH’ A N D T. s. REEVE^ Royal North Shore Hospital of Sydney A comparison is presented of the complications found in two series each consisting of 331 consecutzve patients undergozng thyrordectomy In the some Unit ten sear: apart. T h e overall zrzcidence of postoperative complications has bee% redztced, particularly in the group of patients having thyroidectomy for thyrotoxicosis, following which it is n o w no greater than after thyroidectomy for benign non-toxic goitre. T h e techniques used to try to reduce the postoperative complication rote are discussed. T h e incidence of permanent recurrent laryngeal nerve palsy has been reduced to 0.3% and of permanent hypoparathyroidism to 1.2%. T h e overall incidence of complications causing permanent disability is now 3.9%.
TIIYROIDECTOMY is a commonly performed procedure which involves meticulous attention to anatomical detail and surgical technique. If it is to be performed with a low incidence of postoperative morbidity,‘ the surgeon must be IThis work has been supported in part by the Surgical Research Fund of the Royal North Shore Hospital. Honorary Surgeon (Relieving) Hornsby and District Hospital, N.S.W. ; latterly Senior Surgical Registrar, The Royal North Shore Hospital and Registrar to The Professorial Subunit in Surgery of The University of Sydney at the Royal North Shore Hospital. 8Professor of Surgery, University of Sydney at The Royal North Shore Hospital. Reprints : Professor T. S. Reeve, Professorial Surgical Unit. University of Sydney at The Royal North Shore Hospital, S t Leonards, N.S.W. 2065.
Ausr. N.Z. J. Suac., VOL. 45-No.
closely involved in the preoperative assessment, preparation for surgery and postoperative care of his patients. T h e object of this paper is to review the postoperative complications in a consecutive series of 331 patients who underwent thyroidectomy and to compare the morbidity with that associated with a similar series of patients who had undergone operation ten years previously (Series I) (Reeve et a%, 1966).
I, FEBRUARY, 1975
CLINICAL RECORDS Between June 30, 1971 and July 26, 1972, thyroidectomy was performed on 331 patients following assessment at the Thyroid Investigation Clinic of The Royal North Shore Hospital of Sydney. These patients have been followed for a period of at least twelve months after surgery (Table I ) . 21
BARRACLOUCH AND REEVE
COMPLICATIONS OF THYROIDECTOMY 77
EZl
Series I
0S e r i e s II
70
60
50
40
30
20
10
0-
9 10-19
20-29
30-39
40-49
50-59
FIGUREI: Series I, 331 patients, January I, 1956 to December 31, 1962; females, 285; males, 46. Series 11, 331 patients, June 30, 1971to July 26, 1972; females, 304; males, 27.
There were 304 females and 27 males, and their ages ranged from 12 to 87 years (comparison with Series I can be made by referring to Table I and Figure I ) . In this series, 157 patients had non-toxic nodular goitre, 136 thyrotoxicosis, 25 thyroiditis and 13 malignancy (Table 2). Twenty-seven patients (8.1%) had retrosternal extension of their goitre.
pected malignancy, obstructive or potentially obstructive problems in relation to the trachea, cesophagus or superior vena cava, thyrotoxicosis when judged not responsive to conservaTABLE2 Non-toxic nodular goitre
Malignancy Thyrotoxicosis Thyroiditis
TABLEr
..
Series I :
Series1 Series11
Indications for thyroidectomy. -Thyroidectomy was used in the definitive management of patients with thyroid malignancy or sus-
tive management (Hales et a%, I@v), and in those patients with large and unsightly goitres not responding to suppressive dosage of thyroxine.
371 patients, January I, 1956 to December 31, 1962. Females 285, males 46. Series I1 : 331 patients, June 30. 1971 to July 26, 1972. Females 304, m a l e 27.
22
..
63 4%) 157 147'4%)
210
30(9'1%) 13 (3'9%)
AUST. N.Z. J. SURG.,VOL.45-No.
I,
FEBRUARY,1975
COMPLICATIONS OF THYROIDECTOMY Operative Procedure The types of operation performed are listed in Table 3. The gross pathology of each patient's thyroid gland was assessed at operation, and the appropriate operation was performed. A total lobectomy with isthmectomy was used almost exclusively as a first step in patients with nodules arousing suspicion of thyroid cancer, as for instance a single nodule in a lobe or a lobe containing a dominant nodule. TABLE3 Operative Procedures Series I I
.
Bilateral subtotal thyroidectomy . Subtotal lobectomy Total Iobectomy and isihmectbmy . ' Total lobectomy and subtotal lobectbmy other side Total thyroidecidmy 1: Miscellaneous procedures .. ,. Registrar operations . . . . ..
::
::
.. ' '
br
::. .
..
Series I1
--
_ I _
161
1q8
16 79
18 72
26 28
31
21
25%
12 0
34.4%
Frozen section examination was carried out as a routine in cases of nodular goitre. Where a diagnosis of thyroid cancer was made, total thyroidectomy was performed (Hales et aG, 19693). One of these patients had bilateral modified neck dissection as well as total thyroidectomy and tracheostomy. Another patient had unilateral modified neck dissection and total thyroidectomy. Total thyroidectomy was performed in one patient with a benign multinodular goitre, and in another who was thyrotoxic. In the thyrotoxic patient the operation was done in two stages, the second being done after the initial paraffin sections were interpreted as containing malignancy ; this ultimately proved to be incorrect. Ten patients with recurrent goitre ( 3 % ) following previous thyroidectomy had a further thyroidectomy performed. The operations were performed by three surgeons and their registrars, 34.4% of operations being performed by surgical registrars under supervision. I n Series I, 2 5 % of operations were performed by registrars. The operative techniques used were those described by Lahey (1938, I947), and subsequently modified, by Rundle (1951). Further modifications have been made, and in this group of patients the inferior thyroid artery is not ligated in subtotal thyroidectomy, and in total lobectomy its branches are ligated and divided as they enter the thyroid gland itself. This is done in an attempt to preserve the
BARRACLOUGH AND REEVE blood supply of the parathyroid glands, as both superior and inferior glands are supplied by branches of the inferior thyroid artery and only rarely by branches of the superior artery (Halstead and Evans, 1907; Hunt et alii, 1968). If the parathyroid glands are found on the surface of the lobe to be removed, they are carefully dissected from the gland capsule and left with their blood supply intact. The recurrent laryngeal nerve is identified in all cases. The external laryngeal nerve is protected by ligating and dividing each branch of the superior thyroid artery as it enters the capsule of the upper pole of the gland, rather than by mass ligation of the superior vascular pedicle ( H u n t e t dii, 1968). This nerve most commonly lies in close proximity to the medial aspect of the vascular pedicle of the superior pole before entering the larynx, and may be observed in about 70% of cases in close relationship to the medial aspect of the superior pole of the thyroid gland (Durham and Harrison, 1964; Reeve et alii, 1969). Approximately 4% of nerves are deemed vulnerable. The pyramidal lobe is totally excised, as it may later undergo hypertrophy. This is particularly important in operations for suspected malignancy. When thyroidectomy was performed for retrosternal goitre the operative principles reported earlier by Reeve et alii (1962) and Reeve (1972) were followed, and it was not found necessary to split the sternum in any of these operations.
DISCUSSION OF RESULTS T h e patients have been divided into four separate categories to allow comparison of morbidity data with those reported by Reeve et alii (1966) in respect of a similar series of operations performed between January I, 1956 and December 31, 1962. These categories are non-toxic nodular goitre, thyrotoxicosis, malignancy and thyroiditis. As can be seen by comparing the two series (Table 2 ) the number of patients with thyrotoxicosis and thyroiditis was greater, and patients with carcinoma and nontoxic nodular goitre were fewer.
Mortality In the present series one death occurred (0.3%), which was not related to the thyroid surgery but followed a colostomy for carcinoma of the colon. I n Series I, two deaths occurred (06%), one on the night following surgery and due to cerebral edema, and one due to staphylococcal pneumonia, occurring three weeks after thyroidectomy for malignancy. T h e details are summarized in Table 4. Recurrent Laryngeal Nerve Palsy Recurrent laryngeal nerve injury causing vocal cord paralysis is a hazard which is of the
BARRACLOUGH AND REEVE
COMPLICATIONS OF THYROIDECTOMY TABLE4
Non-toxic nodular goitre Series
. . . . . . . . . . . . . . . . . . . .
Number of patients Deaths
Malignant
Thyrotoxicosis
I
I1
I
I1
I
I1
I
I1
I
I1
157
30
13
a2
136
9
25
331
33'
0
I
I
0
I
0
0
0
Non-toxic nodular goitre
. . . .
Permanent recurrent laryngeal nerve palsy . . . . . .
5
Malignant
Thyrotoxicosis
Thyroiditis
Total
___-_-_
I
I1
I
I1
I
I1
I
I1
I
I1
210
157
30
13
a2
136
9
25
331
331
2
0
2.
0
0
1
0
0
4' 1.2%
Temporary recurrent laryngeal nerve palsy . . . . . .
* Intentional division of nerve in 2 24
(0.3%)
transient cord dysfunction, may not be accurately detected without indirect laryngoscopy (Blackburn and Salmon, 1961 ; Wade, 1972). Three patients with recurrent goitre were found to have recurrent laryngeal nerve damage following thyroidectomy at other institutions some time previously. Although this measure is not a substitute for a subsequent indirect laryngoscopy, the anzsthetist should, if technically possible, observe the vocal cords at the conclusion of the operation, as it is most useful to be warned of laryngeal cedema or cord dysfunction, which may cause respiratory embarrassment after operation. Laryngeal e d e m a has not been a problem in Series IT and was seen after only one operation, which involved tracheostomy as well as bilateral neck dissection and total thyroidectomy. The relevant figures appear below, in Table 5. Voice changes without recurrent laryngeal nerve palsy.-This problem is not usually serious, but may be significant if the patient is a professional singer or teacher or is engaged in any occupation where he or she depends on voice control. Three patients (0.9%) had deeper voices after operation, and five (1.5%) had transiently weaker voices. 'This problem is related to external laryngeal nerve injury,
_ _ _ _ - ~ . . . . . . . .
I
2
(0.6%)
TABLE
Number of patients
Total
210
utmost concern to both the thyroid surgeon and the anathetist. It is widely accepted that identification of the recurrent laryngeal nerve at operation results in a lower rate of nerve injury; Riddell (1970) had an incidence of injury of 06% and 2.0% for identified and unindentified nerves respectively. It is our practice to identify the ipsilateral nerve if any part of that lobe of the gland is to be resected. One patient ( 0 3 % ) suffered permanent recurrent laryngeal nerve palsy, and six ( 1 4 % ) had transient paresis with full return of function within six months. I n Series I, four patients (1.2%) had permanent recurrent Iaryngeal nerve palsy, but in two of these patients, who had advanced cancer, the recurrent nerve was sectioned intentionally, giving' an incidence of unintentional injury of 0.6%. The incidence of 0.6% in Series I and 0.3% in Series TI is comparable with the results of other workers who expose the nerve in all cases (Mountain et nlii. 1971 ; Wade, 1961). All patients who have thyroidectomy have their laryngeal function assessed by an ear, nose and throat surgeon. Indirect laryngoscopy is now performed both before and after operation. This was, not done in Series I, and transient nerve paresis was not recorded. Unilateral compensated cord dysfunction, or partial or
Series
Thyroiditis
patients,
3
_
0
-
-
-
I
0.3% 6 1.8%
- Data not recorded for Series I. A u s ~ .N.Z. J. SURG., VOL.45-No.
I,
FEBRUARY, 1975
BARRACLOUGH A N D REEVE
COMPLICATIONSOF THYROIDECTOMY TABLEG Non-toxic nodular goitre
__-
~
Series
. . . . . . . . . . . .
Number of patients
Malignant
Thyrotoxicosis
Thyroiditis
Total
I
I1
I
I1
I
I1
I
I1
I
I1
210
I57
30
13
a2
136
9
25
331
331
palsy p = permanent.
T
=
transient.
and ligation of the individual branches of the superior thyroid artery may help in avoiding injury to this nerve. In Series I, before this technique was in common use, five patients ( 1.5%) had permanent voice changes and ten (3%) had transient voice changes (Table 6) .
H y p o parathyroidism Despite the use of the technique described to help to preserve the parathyroid blood supply and greater familiarity with the normal positions of these glands, four patients (1'3%) developed permanent hypoparathyroidism and seven (2.1 %) developed transient hypoparathyroidism, requiring calcium supplements for a short period of time. I n Series I eight patients (2'4%) had permanent hypoparathyroidism and four ( 1.2%) transient hypoparathyroidism. Hypoparathyroidism may occur after any thyroidectomy, but the patients most likely to suffer from tetany are those having total thyroidectomy for carcinoma. Of those patients undergoing primary surgery, there were two such (20%) in the ten patients in Series 11, compared with three (10.7%) in the 28 patients in Series I. The incidence of hypoparathyroidism following total thyroidectomy for cancer
has been reported to range between 2'30 (Thompson et a%, 1973) and 33% (Harold and Wright, 1966). Of the 22 patients who had total thyroidectomy, completion thyroidectomy or a second thyroidectomy for recurrent goitre, three ( 13.6%) developed permanent hypoparathyroidism. Two of these had previously undergone thyroidectomy elsewhere. In delayed secondary thyroid surgery for malignancy the parathyroid vasculature is at considerable risk. T h e overall rate of permanent hypoparathyroidism has been reduced from 2.4% to 1.2%~ but further reduction of this complication to the level of 0.32% reported by Watkins et alii (1962), in a series of 37,000 thyroid operations at the Lahey Clinic, can only be achieved by careful preservation of the parathyroid glands and their blood supply (Wade et alii, 1965). However, there are others who doubt whether there is any influence of inferior thyroid artery ligation on parathyroid function (Michie et a&, 1965). It is now our practice to perform non-stasis serum calcium estimations (Baume et alii, 1969) on all our patients before operation, and on the first and fifth days following thyroidectomy. If a lowered serum calcium level is associated with any symptoms of hypocalcaemia, the patient is treated and fol-
TABLE7 Non-toxic nodular goitre
Malignant
_______I__-------
I . . . . . . . . __Number of patients . . . . 210
Series
Permanent hypoparathyroidism
I
11
r57
3
I
Thyrotoxicosis
2
I
Total
__-I
~____________________--3'3 13 8z 136 9 25 331 _-__ __-__3
2
2
1
I
2
0
0
_____
Temporary hypoparathyroidism
Thyroiditis
_ _ I _ I1_ _ I ~ I1- ~ I1
I
4
0
8 2.4%
0
4 1-2%
AUST. N.Z. J. SIJRC., VOL.45-No.
I,
FERRUARY, 1975
I1 331
4 1.2%
-
7 2.1%
25
BARRACLOUCH AND REEVE
COMPLICATIONS O F 'rHYROIDECTOMY
lowed closely after leaving hospital, as a number of these patients have only a transient reduction of parathyroid function, and individual replacement requirements vary widely. Serum calcium estimation should always be performed after operation ; otherwise some cases of hypoparathyroidism may be missed (Reeve, 1967, 1969) (Table 7).
W o u n d Reexploration f o r Hewzorrhage This was necessary in one patient only (0.3%), for reactionary hzmorrhage following operation for thyrotoxicosis. I n Series I, nine patients (2.7%) required reexploration for bleeding. As well as improved preoperative preparation, the use of suction drainage both deep to the strap muscles and under the skin flaps may have contributed to this improved result. W o u n d Infection Suction drainage of the neck may also have been a contributory factor in the reduction of the wound infection rate in this series from 6% to 2.4%, and in the thyrotoxic group from 8.4% to 2.2%, by reducing dead space, haematoma formation and collection of serum in the neck wound. It has also been our custom since 1965 to wash all wounds with 5% Milton solution prior to closure (Table 8). Other Complications Directly Related to Thyroid Surgery These are listed in Table 9. Reciirrent thyrotoxicosis. -This occurred in one patient (0.7%) after a second thyroidectomy. This patient was subsequently treated with radioiodine to ablate the small amount of
remaining thyroid tissue. This complication occurs less frequently than hypothyroidism, and an incidence of 2 . 1 % has been reported by Hunter (1967)~1.4% by Michie et alii (1972) and 6% by Hedley et alii (1970). Bilateral subtotal thyroidectomy, leaving approximately two grammes of tissue as the remnant of each lobe, usually produces a satisfactory long-term euthyroid state. TABLEg Other Complications Directly Related to Thyroid Surgery Series I
Series I1
Recurrent thyrotoxicosis . . . . . . I (0.3%) I (0.3%) Hypothyroidism . . . . . . . . 3 (0.9%) 1 (0.3%) . . . . 7 (2.1%) 1(0.3%) Tracheostomy Laryngeal edema. . . . . I(O'3%) Wound adherence to trachea riquiring'reopir: ation . . . . . . . . I l0.70/,1 0 GoitrereGowth . . .. .. .. .. .. .. .. .. 3 i0.X) 0 Neutropenia . . .. .. .. .. .. .. .. .. I (0'3%) Dysphagia I(O'3%) Arteriovenous fiitula . . . . . . . . I (0.3%) o
-
(-
=
not included in data recorded for Series I)
Hypothyroidiswz. - One patient developed hypothyroidism following thyroidectomy for thyrotoxicosis (0.7%). This can occur in up to 6% of cases over a ten-year period (Green and Wilson, 1964)) but more recently Michie et alii (1972) reported a hypothyroidism rate of 49% over a three to five year period, which they related to remnant size. This complication is produced intentionally in those patients having total thyroidectomy for malignancy, exophthalmos (Catz and Perzik, 1965) or neartotal thyroidectomy for nodular goitre in which there is little normal thyroid tissue, who are therefore excluded from our results. These patients were treated with appropriate replacement dosage of thyroxine.
TABLE8 Non-toxic nodular goitre
-
. . . . . . . . I Number of patients . . . . _____210
Series
Wound re-exploration for h e morrhage . . . . . .
Wound infection
26
. . . .
3
a
Malignant
Thyrotoxicosis
Thyroiditis
Total
-
~-
I1
I
I1
I
I1
I
I1
I
11
157
30
13
82
136
9
25
331
331
0
0
0
6
1
0
0
9 2'7%
4
2
I
7
3
3
20
0
6.0%
AUST. N.Z. J. SURG., VOL. 45-NO.
I,
I
0.3%
P
I% ”.
ILL.
WADE,J. S., GCODALL, P., DEANE,L., DANCY,T. M. and FOURMAN, P. (1g65), Brit. J. Surg., 5 2 : 497. WATKINS,E., BELL,G. O., SNOW, J. C. and ADAMS, H. D. (rg62), J. Amer. med. Ass., 184: 138.
COMPLICATIONS OF THYROIDECTOMY REFERENCES BELL, G. and SHORT,D. W. (1g72), Brit. J. Surg., 59: 429.
FOLKOW,B. and NEIL, E. (1971), “Circulation”, Oxford University Press, New York, London, Toronto. GOODMAN,A. H. and LI~TLE, J. M. (I971), Mod. Med. Aust., 13: 81. LEE, B. Y . and TRAINOR, F. S. (IQ73), “Peripheral Vascular Surgery : Hanodynamics of Arterial
Pulsatile Blood Flow”, Appleton-Century-Crofts, New York. LITTLE,J. M., SHEIL,A. G. R., LOEWENTHAL, J. and GOODMAN, A. H. (1968), Lancet, 2: 648. MUNKO, R. (1973), personal communication. WEALE, F. E. (1969). Ann. Surg., 169: 489. WESOLOWSKI, S. A., MARTINEZ,A,, DOMINGO, R. T., FRIES, C. L., SCHAEFFER, H. L., SAWYER, P. N., GILLIE,E. and MCMAHON, J. D. (1966), Surgery, 60: 288.
Postoperative Complications of Thyroidectomy : A Comparison of Two Series at an Interval of Ten Years’ B. H. BARRACLOUGH’ A N D T. s. REEVE^ Royal North Shore Hospital of Sydney A comparison is presented of the complications found in two series each consisting of 331 consecutzve patients undergozng thyrordectomy In the some Unit ten sear: apart. T h e overall zrzcidence of postoperative complications has bee% redztced, particularly in the group of patients having thyroidectomy for thyrotoxicosis, following which it is n o w no greater than after thyroidectomy for benign non-toxic goitre. T h e techniques used to try to reduce the postoperative complication rote are discussed. T h e incidence of permanent recurrent laryngeal nerve palsy has been reduced to 0.3% and of permanent hypoparathyroidism to 1.2%. T h e overall incidence of complications causing permanent disability is now 3.9%.
TIIYROIDECTOMY is a commonly performed procedure which involves meticulous attention to anatomical detail and surgical technique. If it is to be performed with a low incidence of postoperative morbidity,‘ the surgeon must be IThis work has been supported in part by the Surgical Research Fund of the Royal North Shore Hospital. Honorary Surgeon (Relieving) Hornsby and District Hospital, N.S.W. ; latterly Senior Surgical Registrar, The Royal North Shore Hospital and Registrar to The Professorial Subunit in Surgery of The University of Sydney at the Royal North Shore Hospital. 8Professor of Surgery, University of Sydney at The Royal North Shore Hospital. Reprints : Professor T. S. Reeve, Professorial Surgical Unit. University of Sydney at The Royal North Shore Hospital, S t Leonards, N.S.W. 2065.
Ausr. N.Z. J. Suac., VOL. 45-No.
closely involved in the preoperative assessment, preparation for surgery and postoperative care of his patients. T h e object of this paper is to review the postoperative complications in a consecutive series of 331 patients who underwent thyroidectomy and to compare the morbidity with that associated with a similar series of patients who had undergone operation ten years previously (Series I) (Reeve et a%, 1966).
I, FEBRUARY, 1975
CLINICAL RECORDS Between June 30, 1971 and July 26, 1972, thyroidectomy was performed on 331 patients following assessment at the Thyroid Investigation Clinic of The Royal North Shore Hospital of Sydney. These patients have been followed for a period of at least twelve months after surgery (Table I ) . 21
BARRACLOUCH AND REEVE
COMPLICATIONS OF THYROIDECTOMY 77
EZl
Series I
0S e r i e s II
70
60
50
40
30
20
10
0-
9 10-19
20-29
30-39
40-49
50-59
FIGUREI: Series I, 331 patients, January I, 1956 to December 31, 1962; females, 285; males, 46. Series 11, 331 patients, June 30, 1971to July 26, 1972; females, 304; males, 27.
There were 304 females and 27 males, and their ages ranged from 12 to 87 years (comparison with Series I can be made by referring to Table I and Figure I ) . In this series, 157 patients had non-toxic nodular goitre, 136 thyrotoxicosis, 25 thyroiditis and 13 malignancy (Table 2). Twenty-seven patients (8.1%) had retrosternal extension of their goitre.
pected malignancy, obstructive or potentially obstructive problems in relation to the trachea, cesophagus or superior vena cava, thyrotoxicosis when judged not responsive to conservaTABLE2 Non-toxic nodular goitre
Malignancy Thyrotoxicosis Thyroiditis
TABLEr
..
Series I :
Series1 Series11
Indications for thyroidectomy. -Thyroidectomy was used in the definitive management of patients with thyroid malignancy or sus-
tive management (Hales et a%, I@v), and in those patients with large and unsightly goitres not responding to suppressive dosage of thyroxine.
371 patients, January I, 1956 to December 31, 1962. Females 285, males 46. Series I1 : 331 patients, June 30. 1971 to July 26, 1972. Females 304, m a l e 27.
22
..
63 4%) 157 147'4%)
210
30(9'1%) 13 (3'9%)
AUST. N.Z. J. SURG.,VOL.45-No.
I,
FEBRUARY,1975
COMPLICATIONS OF THYROIDECTOMY Operative Procedure The types of operation performed are listed in Table 3. The gross pathology of each patient's thyroid gland was assessed at operation, and the appropriate operation was performed. A total lobectomy with isthmectomy was used almost exclusively as a first step in patients with nodules arousing suspicion of thyroid cancer, as for instance a single nodule in a lobe or a lobe containing a dominant nodule. TABLE3 Operative Procedures Series I I
.
Bilateral subtotal thyroidectomy . Subtotal lobectomy Total Iobectomy and isihmectbmy . ' Total lobectomy and subtotal lobectbmy other side Total thyroidecidmy 1: Miscellaneous procedures .. ,. Registrar operations . . . . ..
::
::
.. ' '
br
::. .
..
Series I1
--
_ I _
161
1q8
16 79
18 72
26 28
31
21
25%
12 0
34.4%
Frozen section examination was carried out as a routine in cases of nodular goitre. Where a diagnosis of thyroid cancer was made, total thyroidectomy was performed (Hales et aG, 19693). One of these patients had bilateral modified neck dissection as well as total thyroidectomy and tracheostomy. Another patient had unilateral modified neck dissection and total thyroidectomy. Total thyroidectomy was performed in one patient with a benign multinodular goitre, and in another who was thyrotoxic. In the thyrotoxic patient the operation was done in two stages, the second being done after the initial paraffin sections were interpreted as containing malignancy ; this ultimately proved to be incorrect. Ten patients with recurrent goitre ( 3 % ) following previous thyroidectomy had a further thyroidectomy performed. The operations were performed by three surgeons and their registrars, 34.4% of operations being performed by surgical registrars under supervision. I n Series I, 2 5 % of operations were performed by registrars. The operative techniques used were those described by Lahey (1938, I947), and subsequently modified, by Rundle (1951). Further modifications have been made, and in this group of patients the inferior thyroid artery is not ligated in subtotal thyroidectomy, and in total lobectomy its branches are ligated and divided as they enter the thyroid gland itself. This is done in an attempt to preserve the
BARRACLOUGH AND REEVE blood supply of the parathyroid glands, as both superior and inferior glands are supplied by branches of the inferior thyroid artery and only rarely by branches of the superior artery (Halstead and Evans, 1907; Hunt et alii, 1968). If the parathyroid glands are found on the surface of the lobe to be removed, they are carefully dissected from the gland capsule and left with their blood supply intact. The recurrent laryngeal nerve is identified in all cases. The external laryngeal nerve is protected by ligating and dividing each branch of the superior thyroid artery as it enters the capsule of the upper pole of the gland, rather than by mass ligation of the superior vascular pedicle ( H u n t e t dii, 1968). This nerve most commonly lies in close proximity to the medial aspect of the vascular pedicle of the superior pole before entering the larynx, and may be observed in about 70% of cases in close relationship to the medial aspect of the superior pole of the thyroid gland (Durham and Harrison, 1964; Reeve et alii, 1969). Approximately 4% of nerves are deemed vulnerable. The pyramidal lobe is totally excised, as it may later undergo hypertrophy. This is particularly important in operations for suspected malignancy. When thyroidectomy was performed for retrosternal goitre the operative principles reported earlier by Reeve et alii (1962) and Reeve (1972) were followed, and it was not found necessary to split the sternum in any of these operations.
DISCUSSION OF RESULTS T h e patients have been divided into four separate categories to allow comparison of morbidity data with those reported by Reeve et alii (1966) in respect of a similar series of operations performed between January I, 1956 and December 31, 1962. These categories are non-toxic nodular goitre, thyrotoxicosis, malignancy and thyroiditis. As can be seen by comparing the two series (Table 2 ) the number of patients with thyrotoxicosis and thyroiditis was greater, and patients with carcinoma and nontoxic nodular goitre were fewer.
Mortality In the present series one death occurred (0.3%), which was not related to the thyroid surgery but followed a colostomy for carcinoma of the colon. I n Series I, two deaths occurred (06%), one on the night following surgery and due to cerebral edema, and one due to staphylococcal pneumonia, occurring three weeks after thyroidectomy for malignancy. T h e details are summarized in Table 4. Recurrent Laryngeal Nerve Palsy Recurrent laryngeal nerve injury causing vocal cord paralysis is a hazard which is of the
BARRACLOUGH AND REEVE
COMPLICATIONS OF THYROIDECTOMY TABLE4
Non-toxic nodular goitre Series
. . . . . . . . . . . . . . . . . . . .
Number of patients Deaths
Malignant
Thyrotoxicosis
I
I1
I
I1
I
I1
I
I1
I
I1
157
30
13
a2
136
9
25
331
33'
0
I
I
0
I
0
0
0
Non-toxic nodular goitre
. . . .
Permanent recurrent laryngeal nerve palsy . . . . . .
5
Malignant
Thyrotoxicosis
Thyroiditis
Total
___-_-_
I
I1
I
I1
I
I1
I
I1
I
I1
210
157
30
13
a2
136
9
25
331
331
2
0
2.
0
0
1
0
0
4' 1.2%
Temporary recurrent laryngeal nerve palsy . . . . . .
* Intentional division of nerve in 2 24
(0.3%)
transient cord dysfunction, may not be accurately detected without indirect laryngoscopy (Blackburn and Salmon, 1961 ; Wade, 1972). Three patients with recurrent goitre were found to have recurrent laryngeal nerve damage following thyroidectomy at other institutions some time previously. Although this measure is not a substitute for a subsequent indirect laryngoscopy, the anzsthetist should, if technically possible, observe the vocal cords at the conclusion of the operation, as it is most useful to be warned of laryngeal cedema or cord dysfunction, which may cause respiratory embarrassment after operation. Laryngeal e d e m a has not been a problem in Series IT and was seen after only one operation, which involved tracheostomy as well as bilateral neck dissection and total thyroidectomy. The relevant figures appear below, in Table 5. Voice changes without recurrent laryngeal nerve palsy.-This problem is not usually serious, but may be significant if the patient is a professional singer or teacher or is engaged in any occupation where he or she depends on voice control. Three patients (0.9%) had deeper voices after operation, and five (1.5%) had transiently weaker voices. 'This problem is related to external laryngeal nerve injury,
_ _ _ _ - ~ . . . . . . . .
I
2
(0.6%)
TABLE
Number of patients
Total
210
utmost concern to both the thyroid surgeon and the anathetist. It is widely accepted that identification of the recurrent laryngeal nerve at operation results in a lower rate of nerve injury; Riddell (1970) had an incidence of injury of 06% and 2.0% for identified and unindentified nerves respectively. It is our practice to identify the ipsilateral nerve if any part of that lobe of the gland is to be resected. One patient ( 0 3 % ) suffered permanent recurrent laryngeal nerve palsy, and six ( 1 4 % ) had transient paresis with full return of function within six months. I n Series I, four patients (1.2%) had permanent recurrent Iaryngeal nerve palsy, but in two of these patients, who had advanced cancer, the recurrent nerve was sectioned intentionally, giving' an incidence of unintentional injury of 0.6%. The incidence of 0.6% in Series I and 0.3% in Series TI is comparable with the results of other workers who expose the nerve in all cases (Mountain et nlii. 1971 ; Wade, 1961). All patients who have thyroidectomy have their laryngeal function assessed by an ear, nose and throat surgeon. Indirect laryngoscopy is now performed both before and after operation. This was, not done in Series I, and transient nerve paresis was not recorded. Unilateral compensated cord dysfunction, or partial or
Series
Thyroiditis
patients,
3
_
0
-
-
-
I
0.3% 6 1.8%
- Data not recorded for Series I. A u s ~ .N.Z. J. SURG., VOL.45-No.
I,
FEBRUARY, 1975
BARRACLOUGH A N D REEVE
COMPLICATIONSOF THYROIDECTOMY TABLEG Non-toxic nodular goitre
__-
~
Series
. . . . . . . . . . . .
Number of patients
Malignant
Thyrotoxicosis
Thyroiditis
Total
I
I1
I
I1
I
I1
I
I1
I
I1
210
I57
30
13
a2
136
9
25
331
331
palsy p = permanent.
T
=
transient.
and ligation of the individual branches of the superior thyroid artery may help in avoiding injury to this nerve. In Series I, before this technique was in common use, five patients ( 1.5%) had permanent voice changes and ten (3%) had transient voice changes (Table 6) .
H y p o parathyroidism Despite the use of the technique described to help to preserve the parathyroid blood supply and greater familiarity with the normal positions of these glands, four patients (1'3%) developed permanent hypoparathyroidism and seven (2.1 %) developed transient hypoparathyroidism, requiring calcium supplements for a short period of time. I n Series I eight patients (2'4%) had permanent hypoparathyroidism and four ( 1.2%) transient hypoparathyroidism. Hypoparathyroidism may occur after any thyroidectomy, but the patients most likely to suffer from tetany are those having total thyroidectomy for carcinoma. Of those patients undergoing primary surgery, there were two such (20%) in the ten patients in Series 11, compared with three (10.7%) in the 28 patients in Series I. The incidence of hypoparathyroidism following total thyroidectomy for cancer
has been reported to range between 2'30 (Thompson et a%, 1973) and 33% (Harold and Wright, 1966). Of the 22 patients who had total thyroidectomy, completion thyroidectomy or a second thyroidectomy for recurrent goitre, three ( 13.6%) developed permanent hypoparathyroidism. Two of these had previously undergone thyroidectomy elsewhere. In delayed secondary thyroid surgery for malignancy the parathyroid vasculature is at considerable risk. T h e overall rate of permanent hypoparathyroidism has been reduced from 2.4% to 1.2%~ but further reduction of this complication to the level of 0.32% reported by Watkins et alii (1962), in a series of 37,000 thyroid operations at the Lahey Clinic, can only be achieved by careful preservation of the parathyroid glands and their blood supply (Wade et alii, 1965). However, there are others who doubt whether there is any influence of inferior thyroid artery ligation on parathyroid function (Michie et a&, 1965). It is now our practice to perform non-stasis serum calcium estimations (Baume et alii, 1969) on all our patients before operation, and on the first and fifth days following thyroidectomy. If a lowered serum calcium level is associated with any symptoms of hypocalcaemia, the patient is treated and fol-
TABLE7 Non-toxic nodular goitre
Malignant
_______I__-------
I . . . . . . . . __Number of patients . . . . 210
Series
Permanent hypoparathyroidism
I
11
r57
3
I
Thyrotoxicosis
2
I
Total
__-I
~____________________--3'3 13 8z 136 9 25 331 _-__ __-__3
2
2
1
I
2
0
0
_____
Temporary hypoparathyroidism
Thyroiditis
_ _ I _ I1_ _ I ~ I1- ~ I1
I
4
0
8 2.4%
0
4 1-2%
AUST. N.Z. J. SIJRC., VOL.45-No.
I,
FERRUARY, 1975
I1 331
4 1.2%
-
7 2.1%
25
BARRACLOUCH AND REEVE
COMPLICATIONS O F 'rHYROIDECTOMY
lowed closely after leaving hospital, as a number of these patients have only a transient reduction of parathyroid function, and individual replacement requirements vary widely. Serum calcium estimation should always be performed after operation ; otherwise some cases of hypoparathyroidism may be missed (Reeve, 1967, 1969) (Table 7).
W o u n d Reexploration f o r Hewzorrhage This was necessary in one patient only (0.3%), for reactionary hzmorrhage following operation for thyrotoxicosis. I n Series I, nine patients (2.7%) required reexploration for bleeding. As well as improved preoperative preparation, the use of suction drainage both deep to the strap muscles and under the skin flaps may have contributed to this improved result. W o u n d Infection Suction drainage of the neck may also have been a contributory factor in the reduction of the wound infection rate in this series from 6% to 2.4%, and in the thyrotoxic group from 8.4% to 2.2%, by reducing dead space, haematoma formation and collection of serum in the neck wound. It has also been our custom since 1965 to wash all wounds with 5% Milton solution prior to closure (Table 8). Other Complications Directly Related to Thyroid Surgery These are listed in Table 9. Reciirrent thyrotoxicosis. -This occurred in one patient (0.7%) after a second thyroidectomy. This patient was subsequently treated with radioiodine to ablate the small amount of
remaining thyroid tissue. This complication occurs less frequently than hypothyroidism, and an incidence of 2 . 1 % has been reported by Hunter (1967)~1.4% by Michie et alii (1972) and 6% by Hedley et alii (1970). Bilateral subtotal thyroidectomy, leaving approximately two grammes of tissue as the remnant of each lobe, usually produces a satisfactory long-term euthyroid state. TABLEg Other Complications Directly Related to Thyroid Surgery Series I
Series I1
Recurrent thyrotoxicosis . . . . . . I (0.3%) I (0.3%) Hypothyroidism . . . . . . . . 3 (0.9%) 1 (0.3%) . . . . 7 (2.1%) 1(0.3%) Tracheostomy Laryngeal edema. . . . . I(O'3%) Wound adherence to trachea riquiring'reopir: ation . . . . . . . . I l0.70/,1 0 GoitrereGowth . . .. .. .. .. .. .. .. .. 3 i0.X) 0 Neutropenia . . .. .. .. .. .. .. .. .. I (0'3%) Dysphagia I(O'3%) Arteriovenous fiitula . . . . . . . . I (0.3%) o
-
(-
=
not included in data recorded for Series I)
Hypothyroidiswz. - One patient developed hypothyroidism following thyroidectomy for thyrotoxicosis (0.7%). This can occur in up to 6% of cases over a ten-year period (Green and Wilson, 1964)) but more recently Michie et alii (1972) reported a hypothyroidism rate of 49% over a three to five year period, which they related to remnant size. This complication is produced intentionally in those patients having total thyroidectomy for malignancy, exophthalmos (Catz and Perzik, 1965) or neartotal thyroidectomy for nodular goitre in which there is little normal thyroid tissue, who are therefore excluded from our results. These patients were treated with appropriate replacement dosage of thyroxine.
TABLE8 Non-toxic nodular goitre
-
. . . . . . . . I Number of patients . . . . _____210
Series
Wound re-exploration for h e morrhage . . . . . .
Wound infection
26
. . . .
3
a
Malignant
Thyrotoxicosis
Thyroiditis
Total
-
~-
I1
I
I1
I
I1
I
I1
I
11
157
30
13
82
136
9
25
331
331
0
0
0
6
1
0
0
9 2'7%
4
2
I
7
3
3
20
0
6.0%
AUST. N.Z. J. SURG., VOL. 45-NO.
I,
I
0.3%
P
I% ”.
ILL.
WADE,J. S., GCODALL, P., DEANE,L., DANCY,T. M. and FOURMAN, P. (1g65), Brit. J. Surg., 5 2 : 497. WATKINS,E., BELL,G. O., SNOW, J. C. and ADAMS, H. D. (rg62), J. Amer. med. Ass., 184: 138.
