Safety and Efficacy of Total Thyroidectomy inHands of Endocrine Surgery Trainees

Anjali Mishra, MS, PDC, Gaurav Agarwal, MS, DNB, PDC, Amit Agarwal, MS,Saroj K. Mishra, MS, DNB, FACS, Lucknow, India

BACKGROUND: Fear of a high complication rate oftotal thyroidectomy, especially in the hands ofless experienced surgeons, limits its routine use.The results of total thyroidectomy in the handsof endocrine surgery trainees and consultantswere compared to know whether this procedurecan be performed effectively and safely by train-ees.

METHODS: Medical records of 232 patients whounderwent total thyroidectomy from 1990 to 1997were reviewed. Patients were put into groups A(operated by consultants) and B (trainees). Safety(postoperative hypoparathyroidism, recurrent la-ryngeal nerve palsy, and hemorrhage) and effi-cacy (postoperative radioactive iodine uptake) inthe two groups were compared.

RESULTS: There were 127 patients in group A and105 in group B. Rates of occurrence of perma-nent hypoparathyroidism and recurrent laryngealnerve palsy were comparable in the two groups.Postoperative radioactive iodine uptake in thetwo groups was not significantly different.

CONCLUSIONS: Total thyroidectomy can be safelyand effectively performed by endocrine surgicaltrainees. Am J Surg. 1999;178:377–380. © 1999by Excerpta Medica, Inc.

Total thyroidectomy has a definite place in the man-agement of malignant and some benign thyroiddisorders.1,2 However, many surgeons debate its rou-

tine use, mainly because of a reportedly higher risk ofcomplications, namely, recurrent laryngeal nerve palsy andpostoperative hypocalcemia, compared with less than totalthyroidectomy procedures.3 The complication rates are ap-parently higher when the procedure is performed by lessexperienced surgeons. Many authors have reported remark-ably low complication rate of total thyroidectomy in thehands of experienced surgeons.1,4 However, there are fewreports addressing the safety of thyroid surgery when per-formed by less experienced surgeons5 or trainees.6 Eventhese studies have not commented on the efficacy of total

thyroidectomy, nor have they provided a comparison of thesafety of the procedure in the hands of trainee and consul-tant surgeons.

Being the only training department of endocrine surgeryin India, which prepares surgeons to practice this surgicalsubspecialty, it appeared prudent for us to address thequestion whether total thyroidectomy can be performedsafely and effectively by less experienced but trained sur-geons. We compared the complication rates of total thy-roidectomy and its completeness in patient groups operatedon by consultant and trainee endocrine surgeons.

MATERIAL AND METHODSMedical records of 232 patients who underwent total

thyroidectomy between January 1990 and December 1997at our center were analyzed. Patients who underwent com-pletion total thyroidectomy (n 5 27) and near total thy-roidectomy (n 5 36) were also included, as the risksinvolved with these procedures are similar to total thyroid-ectomy. The patients were followed up for a minimumperiod of 12 months. Patients were divided in two groups:group A (operated on by consultant surgeons) and group B(operated on by a trainee). All the trainees have at least 3years’ residency training and experience in general surgery.Two consultant surgeons and 6 residents participated dur-ing the study period. Numbers of total thyroidectomy per-formed by individual surgeons are listed in Table I.

As per the protocol of the department, a trainee is al-lowed to perform a total thyroidectomy only after comple-tion of 1 year of endocrine surgical training, assisting a fairnumber of thyroid operations, and performing a minimumof 10 hemithyroidectomies under supervision. The traineesare thus prepared for the total thyroidectomy before per-forming one, which they perform under direct supervisionof a consultant. The consultant surgeon assists the traineefor the entire procedure in most instances. Occasionally,when a relatively experienced trainee (one who has per-formed at least 5 total thyroidectomies) is operating, theconsultant scrubs for the critical steps of nerve and para-thyroid identification only. The consultant remains phys-ically present in the operating room during the entireprocedure, irrespective of whoever is operating. In caseswhere a trainee faces difficulty or a complication occurs oris anticipated, the consultant takes over the case. Suchcases have been put into the group A, ie, those operated onby a consultant.

Surgeons in both the groups use a fairly uniform andstandard operative technique for total thyroidectomy. Ex-ternal branch of superior laryngeal nerve is preserved by itsdemonstration and individual ligation of the vessels of thesuperior thyroid pole close to the lobe. Attempts are madeto demonstrate the entire course of the recurrent laryngeal

From the Department of Endocrine Surgery, Sanjay GandhiPostgraduate Institute of Medical Sciences, Lucknow, India.

Requests for reprints should be addressed to Saroj KantaMishra, MS, DNB, FACS, Additional Professor and Head, Depart-ment of Endocrine Surgery, Sanjay Gandhi Post Graduate Insti-tute of Medical Sciences, Raebareli Road, Lucknow-226 014,India.

Manuscript submitted February 18, 1999, and accepted in re-vised form September 8, 1999.

© 1999 by Excerpta Medica, Inc. 0002-9610/99/$–see front matter 377All rights reserved. PII S0002-9610(99)00196-8

nerves on either side, and to preserve them. The positionsof at least four parathyroid glands are defined, and are leftwithin their fat envelope. Parathyroid glands and theirvascular supply are preserved by individual ligation ofbranches of the inferior thyroid artery on the surface ofthyroid lobe. Utmost care is taken to avoid applying gauzeor suction on the surface of a parathyroid gland.

Safety of total thyroidectomy in terms of temporary (re-covery within 6 months) and permanent postoperativehypocalcemia and recurrent laryngeal nerve palsy werestudied. Postoperative radio-iodine (131I) uptake study wasdone routinely in cases of differentiated thyroid cancersand a few cases of benign goiter to document the efficacy(completeness) of total thyroidectomy.

The chi-square test or Student’s t test was employedwherever appropriate to study the significance of differ-ence.

RESULTSOf the 232 cases, 127 total thyroidectomies were per-

formed by consultant surgeons (group A) and 105 by en-docrine surgery trainees (group B). The indications fortotal thyroidectomy in the two groups are summarized inTable II. Mean age of patients was 43.5 years and 37.7years in group A and group B, respectively. There was nostatistically significant difference in goiter grade except forgrade O goiters (Table III). Toxicity status also did notdiffer in the two groups. In all, 130 thyroidectomies weredone for thyroid malignancies and 102 for benign thyroiddisorders. The distribution of benign and malignant thy-roid disorders did not differ between the two groups. Thebreak-up of type of thyroidectomy and additional surgicalprocedures in the two groups are listed in Table IV.

Three patients with poorly differentiated or anaplasticthyroid cancer died during the perioperative period. One ofthe patients died of respiratory failure due to compressivecervical myelopathy because of metastases from poorlydifferentiated papillary carcinoma. An elderly man withanaplastic carcinoma of thyroid died of mediastinitis fol-lowing a transsternal extirpation of a retrosternal invasivetumor. Another elderly man with anaplastic carcinomadied of multiorgan system failure following septicemiawhile on assisted ventilation.

Thirty-one patients in group A (24.41%) and 11 patientsin group B (10.48%) had extrathyroidal invasion (T4 tu-mors). The distribution of T1, T2, and T3 tumors in group

A and B was 5, 24, 22 (Tx 5 8) and 5, 18, and 6,respectively. There was no statistically significant differ-ence between the two groups in this regard.

None of the patients had bilateral recurrent laryngealnerve palsy. The overall incidences of various complica-tions were temporary hypocalcemia 28.45%, permanenthypocalcemia 1.29%, temporary recurrent laryngeal nervepalsy 4.31%, permanent recurrent laryngeal nerve palsy0.86%, and postoperative hemorrhage 2.59%. Eleven pa-tients with long-standing large goiters suffered tracheoma-lacia, 9 of whom required tracheostomy. Complicationrates in the two groups were comparable (Table IV).

Of the 66 patients who developed temporary hypocalce-mia, 2 had undergone excision of a coexistent parathyroidadenoma, too, and had postoperative hungry bone syn-drome. Two other patients in the group A underwent totalparathyroidectomy and autotransplantation. A known pre-disposing factor for hypocalcemia was present in 47 cases.25 had thyroid cancer (14 widely invasive), 18 were hy-perthyroid, and 4 were retrosternal goiters. In thyroid can-cer patients developing hypocalcemia, 5 cases had under-gone reoperation (with lymph node dissection in 1), and14 cases had cervical lymph node dissection (7 underwent

TABLE INumber of Total Thyroidectomies Performed by Individual

Surgeons

OperatorNumber of TotalThyroidectomies Duration

Consultant 1 120 8 yearsConsultant 2 7 6 monthsTrainee 1 10 3 yearsTrainee 2 9 3 yearsTrainee 3 1 1 year and 3 monthsTrainee 4 34 4 yearsTrainee 5 50 4 yearsTrainee 6 1 1 year and 6 months

TABLE IIIndications for Total Thyroidectomy

IndicationsGroup A(n 5 127)

Group B(n 5 105)

Differentiated thyroid cancer 78 37Medullary thyroid cancer 5 3Anaplastic cancer 5 0Rarer cancers* 2 0Follicular/Hurthle cell adenoma 2 7Euthyroid multinodular goiter 13 39Toxic multinodular goiter 8 5Graves’ disease 13 14Others† 3 0

* Squamous cell carcinoma, malignant hemangio-endothelioma.† Amyloid goiter, lymphocytic thyroiditis.

TABLE IIIClinicopathological Profile of Patients

Group A(n 5 127)

Group B(n 5 105) P Value

Age (mean 6 SD) 43.5 6 14.4 37.7 6 11.8Gender ratio M:F 1:1.59 1:4.5Grade* of goiter

O 19 (15.0%) 5 (04.8%) ,0.05I 33 (26.0%) 35 (33.3%) .0.05II 44 (34.6%) 41 (39.0%) .0.05III 31 (24.4%) 21 (20.0%) .0.05

Retrosternal goiters 5 (3.6%) 2 (1.9%) .0.05Thyroid function

Euthyroid 100 (79.5%) 85 (80.0%) .0.05Hyperthyroid 27 (21.3%) 25 (20.0%) .0.05

Thyroid pathologyBenign 37 (29.1%) 65 (61.9%) .0.05Malignant 90 (70.9%) 40 (38.1%) .0.05

* World Health Organization grading.

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superior mediastinal dissection also). One patient withmultinodular goiter with micropapillary carcinoma and 2with Grave’s disease had permanent hypocalcemia.

Ten patients had temporary recurrent laryngeal nervepalsy. In 1 of these group B patients, a ligature was putinadvertently over the nerve, but it was soon recognizedand the ligature was divided. Another patient with Grave’sdisease who developed neuropraxia had excessive bleedingduring the operation. Six patients with thyroid cancer and2 with multinodular goiter, in whom the nerve wasstretched over a nodule and had to be dissected, alsodeveloped neuropraxia. The vocal cord paralysis recoveredwithin 3 months in all these patients. Permanent recurrentnerve palsy occurred in 1 patient with Grave’s disease andin 1 with widely invasive thyroid cancer.

Postoperative radioactive iodine uptake results of 103patients were available, and were graded as nil uptake,minimal uptake (,2%), and significant uptake (.2%).There was no statistically significant difference in resultsfor these two groups (Table IV).

COMMENTSThe importance of performing safe thyroid surgery can

not be overemphasized, and considerable surgical skills arerequired for performing safe and effective total thyroidec-tomy. Total thyroidectomy is arguably the treatment ofchoice for differentiated thyroid cancers and should beperformed by a surgeon only if the incidence rates of thetwo most dreaded complications, namely, permanent hy-poparathyroidism and permanent recurrent laryngeal nervepalsy, can be kept below 2%.1 Owing to the higher com-plication rate of the procedure, many argue against per-forming total thyroidectomy, especially by less experiencedsurgeons. With experience and meticulous operation tech-nique, the rate of complications can be brought down.4

The incidence of complications in the 232 total thyroid-ectomies in our series is well within the acceptable rates, as

suggested by Clark.1 Permanent hypoparathyroidism andpermanent recurrent laryngeal nerve palsy occurred in1.29% and 0.89% patients, respectively. These figures com-pare favorably with figures reported by others.1,2,4 In ourexperience, preservation of the recurrent laryngeal nervesand parathyroid glands by their identification proves a saferapproach than presumptive safety of these vital structuresby the technique of capsular dissection alone.

The occurrence of temporary hypocalcemia in 28.5% ofour patients undergoing total thyroidectomy may appear abit too high. If the 4 patients who underwent excision of acoexistent parathyroid adenoma or total parathyroidec-tomy and autotransplantation are excluded from the cal-culations, the incidence of hypocalcemia in the remainingpatients is 27.2%. In 47 (75.8%) of the remaining 62patients who had hypocalcemia, one or more known riskfactors for occurrence of this complication were present.Hyperthyroid state, malignancy, and lymph node dissec-tion have been reported as risk factors for occurrence ofpostthyroidectomy hypocalcemia7,8; and 75.8% of our pa-tients having hypocalcemia had one of these predisposingfactors.

Transient hypocalcemia after thyroid surgery is probablya multifactorial phenomenon, and mere preservation ofviable parathyroid glands during surgery may not be suffi-cient to prevent the occurrence of this morbidity.9,10 Apreliminary probe into the cause of high incidence ofpostthyroidectomy hypocalcemia in our patients suggeststhat the widely prevalent vitamin D deficiency and poorcalcium intake and skeletal calcium reserves in the Indianpopulation (unpublished results) may have a role to play.This hypothesis gains strength from the fact that most ofour patients who suffered postoperative hypocalcemia be-came normocalcemic within 3 to 6 months after surgery.As a result, although the incidence of transient hypocal-cemia was high, the incidence of permanent hypocalcemia

TABLE IVOperative Procedures and Outcome

Group A(n 5 127)

Group B(n 5 105)

PValue

Type of surgeryTotal thyroidectomy 84 (66.1%) 85 (80.9%) ,0.05Near total thyroidectomy 26 (20.5%) 10 (9.5%) ,0.05Completion thyroidectomy 17 (13.4%) 10 (9.5%) .0.05

Associated proceduresCervical lymph node dissection 38 (29.0%) 25 (23.8%) .0.05Mediastinal lymph node dissection 14 (11.0%) 1 (0.9%) .0.05

ComplicationsTemporary hypocalcemia 31 (24.4%) 35 (33.3%) .0.05Permanent hypocalcemia 1 (0.8%) 2 (1.9%)Temporary RLN palsy 5 (3.6%) 5 (4.8%) .0.05Permanent RLN palsy 1 (0.8%) 1 (0.9%)Hemorrhage 2 (1.6%) 4 (3.8%) .0.05

Postoperative RAIU (n 5 103) (n 5 53) (n 5 50)Nil 8 (15.1%) 20 (40.0%) .0.05Minimal 24 (45.3%) 19 (38.0%) .0.05Significant 21 (39.6%) 11 (22.0%) .0.05

RLN 5 recurrent laryngeal nerve; RAIU 5 radioactive iodine uptake.

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in our series remained low at 1.29%. The reported inci-dence of transient hypocalcemia after thyroidectomyranges from as low as 1.6% to as high as 53.6%.10 Unlikeour series, most published series reporting a relatively highincidence of transient hypocalcemia have reported a rela-tively high incidence of permanent hypocalcemia, too,ranging from 2.8% to 9.3%.10

General surgery training programs do not give adequateexposure to thyroid surgery.11 As endocrine surgery con-tinues to evolve as a distinct specialty, more and moremajor thyroid operations in future will be performed inspecialized centers by experienced surgeons. General sur-gery residents in future will thus have limited exposure tothyroid surgery. However, with proper training under closesupervision of an experienced surgeon, total thyroidectomyis rendered a safe operation even in hands of traineesurgeons. In a report of 200 thyroid operations performedby residents, 40 of which were total thyroidectomies, 1patient each had transient recurrent laryngeal nerve palsyand transient hypocalcemia. The authors thus concludedthat thyroidectomy is a safe operation in the hands ofresidents with close supervision and assistance by the at-tending surgeons.6 Reeve et al5 found that surgeons prac-ticing at provincial medical centers who have receivedadequate training in the technique of total thyroidectomycould perform it as proficiently as surgeons in specializedendocrine surgical units do. They concluded that the mostimportant factor in the ability to perform safe and totalthyroidectomy is to have received appropriate training.Shaked et al12 have shown that surgery performed byresidents in a teaching institution is quite safe and haveemphasized the need for painstaking supervision and guid-ance of a consultant. This view was supported by Sharma etal,13 who expressed the need to develop a variable that canbe easily monitored in an operative setting. Achievementof skill for performing safe surgery remains a result ofcombined efforts made by a dedicated teacher and a recep-tive trainee.

Performance of effective total thyroidectomy (leaving noor minimum residual thyroid tissue) is equally importantfor adequate primary treatment of thyroid cancer. This isespecially relevant in developing countries like ours withfew centers equipped with facilities for radio-iodine ther-apy. Postoperative radioactive iodine uptake studies re-vealed nil uptake in 27.18% of our patients, which iscomparable to results reported by Clark.1

The authors believe that total thyroidectomy should beperformed by a person who is specifically trained for thisprocedure under the care of experts. This view has beenexpressed by others as well.2,14 Obviously, if such is thecase, the consultant imparting this training should be aperson who is a dedicated endocrine surgeon with consid-erable skills and experience. Our study demonstrates thatwith proper training and supervision, trainees can safelyand effectively perform total thyroidectomy.

REFERENCES1. Clark OH. Total thyroidectomy—the treatment of choice forpatients with differentiated thyroid cancer. Ann Surg. 1982;196:361–370.2. Reeve TS, Delbridge L, Cohen A, Crummer P. Total thyroid-ectomy—the preferred option for multinodular goiter. Ann Surg.1987;206:782–786.3. Hay ID, Grant CS, Taylor WF, McConahey WM. Ipsilaterallobectomy versus bilateral lobar resection in papillary thyroidcarcinoma: a retrospective analysis of surgical outcome using anovel prognostic scoring system. Surgery. 1987;102:1088–1095.4. Harness JK, Fung L, Thompson NW, et al. Total thyroidectomy:complications and technique. World J Surg. 1986;10:781–786.5. Reeve TS, Curtin A, Fingleton L, et al. Can total thyroidectomybe performed safely by general surgeons in provincial centers as bysurgeons in specialized endocrine surgical units? Arch Surg. 1994;129:834–836.6. Shaha A, Jaffe BM. Complications of thyroid surgery performedby residents. Surgery. 1988;104:1109–1114.7. McHenry CR, Speroff T, Wentworth D, Murphy T. Risk factorsfor post-thyroidectomy hypocalcemia. Surgery. 1994;116:641–648.8. Wingert DJ, Friesen SR, Iliopoulos JI, et al. Post-thyroidectomyhypocalcemia: incidence and risk factors. Am J Surg. 1986;152:606–610.9. Bergamaschi R, Becouarn G, Ronceray J, Arnaud J-P. Morbidityof thyroid surgery. Am J Surg. 1998;176:71–75.10. Pattou F, Combemale F, Fabre S, et al. Hypocalcemia followingthyroid surgery: incidence and prediction of outcome. World J Surg.1998;22:718–724.11. Harness JK, Organ CH, Thompson NW. Operative experienceof U.S. general surgery residents in thyroid and parathyroid dis-eases. Surgery. 1995;118:1063–1070.12. Shaked A, Calderom I, Durst A. Safety of surgical proceduresperformed by residents. Arch Surg. 1991;126:559–560.13. Sharma AK, Surange R, Mishra SK. Safety of surgical proce-dures. Arch Surg. 1992;127:993–994. Letter.14. Gough IR. Total thyroidectomy: indications, technique andtraining. Aust NZ J Surg. 1992;62:87–89.

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