An audit of thyroid surgery: the Hyderabad experience.
Objective: To make an audit of thyroid surgery performed in two private hospitals at Hyderabad.
Study design: Descriptive study.
Place and duration of study: This study was carried out at two private hospitals, mainly at Isra University Hospital, Hyderabad over a period of three years from April 2005 to March 2008.
Patients and Methods: 140 patients with goiter were operated after complete investigative work up during the above mentioned period. Various complications of thyroid surgery and histopathology reports were noted and compared with national and international literature.
Results: The benign lesions were 89% while 11% lesions were malignant. Papillary carcinoma was the most common malignant lesion while colloid goiter was the most common benign lesion. The overall complication rate was 10.7%, hypocalcaemia being the most frequent complication followed by recurrent laryngeal nerve (RLN) injury.
Conclusion: Colloid goiter is the most common benign lesion of the thyroid gland while papillary carcinoma is the most common malignant lesion of thyroid gland. The major complications of thyroid surgery were hypocalcaemia and RLN injury.
Thyroid enlargement in the form of solitary, multinodular or diffuse goiter is inexplicably frequent surgical problem and affect approximately one-third of adult world population1. The appropriate clinical management is focused primarily on excluding thyroid cancer and also on evaluating thyroid function and mechanical obstruction. The initial work up should include a complete clinical review, a thyroid ultrasonography, laboratory assessment of thyroid functions and where indicated, a cytological assessment of the nodule by FNAC. Thyroid disorders are more common in females as compared to males and its prevalence increases with age. The prevalence of a palpable thyroid nodule is approximately 5% in women and 1% in men in iodine sufficient parts of the world2. Thyroid surgery is one of the most frequently performed surgical procedure world wide, even if the risks of lethal postoperative complications prevented its evolution and diffusion until the beginning of the 20th century3.
At present, the mortality of this procedure approaches 0% and overall complication rate is less than 3%. Nonetheless, major complications of thyroid surgery (i.e. compressive haematoma, recurrent laryngeal nerve injury and hypoparathyroidism) are still fearful complications.
The objective of this study was to make an audit of thyroid surgery performed in two private hospitals at Hyderabad.
Patients and Methods
This study was carried out at the Isra University Hospital, Hyderabad, a private teaching university hospital and Memon Charitable Hospital, Hyderabad, a private non-teaching hospital over a period of three years from April 2005 to March 2008. All patients with goiter, who underwent any sort of thyroid surgery (i.e. lobectomy, isthmusectomy, subtotal thyroidectomy, near total thyroidectomy or total thyroidectomy) were included in this study. All patients were electively admitted via out patient department. Investigations like thyroid function tests, serum calcium, thyroid scan, ultrasonography and FNAC (where indicated) were performed. Indirect laryngoscopy was done a day before surgery by ENT surgeon to see any preoperative vocal cord abnormality.
Thyroid surgery was performed by collar incision two finger breadths above the sternal notch. Superior and inferior subplatysmal flaps was raised from sternal notch to thyroid cartilage. The strap muscles were not routinely divided except for large goiters. The middle thyroid veins were ligated and divided first whenever found. The superior thyroid pedicle was individually ligated and divided after retracting it downward and laterally after identifying the external branch of superior laryngeal nerve. The recurrent laryngeal nerve (RLN) was identified above the level of the inferior thyroid artery. Inferior thyroid artery was usually ligated in continuity. Procedure was completed according to extent of surgery. The neck was routinely drained with suction drains as long as required. Patients were usually discharged by 48-72 hours postoperatively. All patients had their vocal cords checked at the time of extubation. All patients had serum calcium analysis on the day of surgery and on two subsequent days.
Permanent RLN palsy was labeled when persisting for more than six months after surgery. Patients having serum calcium level less than 7mg/dl, requiring calcium and / or vitamin D supplements and having resolved by six months were defined as having temporary symptomatic hypocalcemia. Patients having serum calcium level less than 7mg/dl for more than six months were defined as having permanent hypocalcemia.
The data was collected on a pre-designed proforma and entered & analyzed in SPSS 16.0 software statistical program.
During the above mentioned study period, 140 patients underwent different thyroid operations ranging from hemithyroidectomy to total thyroidectomy. Female to male ratio was 9:1 with mean age of 32 years (SD+ 8.224) and range of 16-68 years. Of these, 52 (37.1%) were hemithyroidectomies, 57(40.7%) subtotal thyroidectomies (STT), 11 (7.8%) near total thyroidectomies, 19 (13.5%) total thyroidectomies and one (0.7%) was isthmusectomy only.
A total of 125 (89%) lesions were benign and 15 (11%) turned out to be malignant. The commonest benign pathological lesion encountered was colloid goiter accounting for 60% of all thyroid lesions. Other benign lesions were follicular adenoma and lymphocytic thyroiditis observed in 38 (27.1%) and 3 (2%) patients respectively. The overall distribution of thyroid lesions by histopathological type is shown in table 1.
Papillary carcinoma was found to be the commonest malignant thyroid lesion, observed in 6.4% all thyroid lesions. This was followed by follicular carcinoma seen in 2.1% of all thyroid lesions.
The postoperative complication rate was 10.7%. The hypocalcaemia rate was 3.5%, accounted as the most common postoperative complication. Temporary hypocalcaemia was seen in four (2.8%) patients while permanent hypocalcaemia occurred in one (0.7%) patient. The RLN injury was observed in 2.8% of patients. It was temporary neuroprexia in two (1.4%) patients which recovered within one month after surgery. In two (1.4%) patients, there was permanent RLN injury, both of these patients had infiltrating papillary thyroid cancers in the posterior aspect of lobe. The lobe and cancer was carefully dissected out but postoperatively both patients had RLN palsy. Other post operative complications included postoperative bleeding in two (1.4%) patients, seroma formation in two (1.4%) patients, stitch sinus and wound infection each in one patient (0.7%). There was no post operative mortality in this study.
In early twentieth century, thyroidectomy became a safe and acceptable operation with the advent of safe general anaesthesia, antisepsis, fine surgical instruments and development of newer surgical and haemostatic techniques4. Successful thyroid surgery depends upon an intimate knowledge of surgical anatomy of neck with the provision of good operative exposure and skilful dissection to identify and preserve RLN and parathyroid glands.
The overall frequency of non-neoplastic lesions in this study was 89% as compared to 11% of neoplastic lesions. The commonest non neoplastic lesion in this study was colloid goiter including diffuse and multinodular goiters which constituted 60% of the thyroid specimens. This is consistent with some local studies in which multinodular goiter and diffuse colloid goiters were found to be the commonest pathologies of the thyroid lesions5-7. Follicular adenomas were seen in 27.1% of the specimens and it was the 2nd most common benign thyroid lesion. This finding is consistent with the observation of Suster8 and Bouq9 but in contrast to Virk et al showing follicular adenoma to be more common than colloid goiter (65% Vs 30%)10. Follicular adenoma clinically presents as solitary discrete cold nodule. FNAC does not help in differentiating a follicular adenoma and carcinoma, a diagnosis which is dependent upon the presence of capsular and vascular invasion.
This capsular and vascular invasion is not well appreciated in cases of FNAC. That's why the final diagnosis of follicular carcinoma depends upon histopathology report and not on FNAC. Patients with clinically discrete solitary nodules in whom FNAC shows "follicular lesion" should always undergo total lobectomy to exclude the diagnosis of follicular carcinoma on final histopathology report. The overall frequency of malignancy in this study was about 11%. This is consistent with figures from various international studies11,12. but in contrast to Mofti et al observing higher incidence of thyroid malignancies (29%) in a study of 158 patients13. In this study papillary carcinoma was the most common malignant thyroid lesion observed in about 60% (9/15) of the lesions.
The morbidity of thyroidectomy from its specific complications continues to be a matter of concern. The overall postoperative complication rate in this study was 10.7%. Post operative hypocalcaemia can be a significant clinical problem, which may delay patient's discharge and requires a considerable postoperative care in immediate postoperative period. In this study, hypocalcaemia was noted in 3.5% of patients, out of which one patient (0.7%) developed permanent hypocalcaemia. This frequency is consistent with some international14,15 and national studies16-18.
The exact incidence of RLN injury is unknown. Different studies have reported varying prevalence of 0 -14%19-21. This difference in complication rates reflects variation in surgical expertise, nature of operation, number of surgeries performed at that particular center. In this study, the frequency of RLN injury was 2.8%. Out of these, two patients (1.4%) had permanent RLN palsy. Both of these patients had infiltrating papillary thyroid cancers in the posterior aspect of the lobe. There was no palsy in benign groups. The permanent RLN palsy of 1.4% in this study can be compared with recent literature reporting this rate to be between 0.3 to 1.7%19,22,23. The temporary RLN palsy rate of 1.4% in this study is also consistent with the findings observed in some national studies up to 4.7%17,18,24. Identification of RLN at surgery is the fundamental step to avoiding damage.
When this policy is employed, any nerve damage is likely to be a transient neuropraxia and recovery will be expected, usually after a period of few weeks or months. If the nerve has not been identified, then paralysis will be permanent in up to one third of patients whose nerves have been injured. The anatomical relationship of RLN and inferior thyroid artery is highly variable and the operating surgeon should have complete knowledge of the normal as well as abnormal variation of the anatomy of this structure. Ligation in continuity of inferior thyroid artery and careful usage of bipolar diathermy minimizes the risks of RLN injury. However this incidence increases in cases of malignant thyroid diseases as noted by Spear et al25.
Thyroid disorders are one of the common problem encountered in general surgical practice. Colloid goiter is the most common benign lesion of the thyroid gland while papillary carcinoma is the most common malignant lesion of thyroid gland. The major complications of thyroid surgery were hypocalcaemia and RLN injury followed by postoperative bleeding and Seroma formation.
1. Galofre JC, Lomvardias S, Davies TF. Evaluation and treatment of thyroid nodules: a clinical guide. Mt Sinai J Med. 2008; 75: 299-311.
2. Wong KT, Choi FPT, Lee YYP, Ahuja AT. Current role in radionuclide imaging in differentiated thyroid cancer. Cancer Imaging 2008; 8: 159-62.
3. Lombardi CP, Raffaelli M, De Crea C, Traini E, Oraganao L, Sollazzi L et al. Complications in thyroid surgery. Minerva Chir 2007 ; 62 : 395-408.
4. Dionigi G, Rovera F, Boni L, Castano P, Dionigi R. Surgical site infections after thyroidectomy. Surg Infect 2006; 7 Suppl 2: S117-20.
5. Elahi S, Manzoor-ul-Hassan A, Syed Z, Nazeer L, Nagra SA, Hyder SW. A study of goiter among female adolescents referred to centre for nuclear medicine, Lahore. Pak J Med Sci 2005; 21: 56-61.
6. Niazi S, Arshad M, Muneer M. A histopathological audit of thyroid surgical specimens. Annals King Edward Med Coll 2007; 13: 51-6.
7. Imran AA, Majid A, Khan SA. Diagnosis of Enlarged thyroid - an analysis of 250 cases. Ann King Edward Med Coll 2005; 11: 203-4.
8. Suster S. Thyroid tumor with a follicular growth pattern: problem in differential diagnosis. Arch Pathol and Lab Med 2006; 130: 984-8.
9. Bouq YA, Fazili FM, Gaffar HA. A current pattern of surgically treated thyroid diseases in the Medinah region of Saudi Arabia. JK- Practitioner 2006; 13: 9-14.
10. Virk NM, Azeem M, Abbar M, Cheema LM. The pattern of thyroid disease in non-toxic solitary thyroid nodule. Ann King Edward Med Coll 2001; 7: 245-6.
11. Abu-Eshy SA, Al-Shehri MY, Khan AR, Khan GM, Al-Humaidi MA, Malatani TS. Causes of goiter in the Asir region. A histopathological analysis of 361 cases. Ann Saudi Med 1995; 15:1-3.
12. Al-Ghamdi SAA, Ali Reza M, Al-Shehri G. The pattern of surgically treated thyroid diseases in the Bisha Region of Saudi Arabia. Ann Saudi Med 2002; 5: 409-10.
13. Mofti AB, Al Momen AA, Suleiman Si, Jain GC, Assaf HM. Experince with thyroid surgery in Security Forces hospital, Riyadh .Saudi Med J 1991; 12: 504-6.
14. Thomusch O, Machens A, Sekulla C, Ukkat J, Brauckhoff M, Dralle H. The impact of surgical technique on postoperative hypothyroidism in bilateral Thyroid Surgery: A multivariate analysis of 5846 consective cases. Surgery 2003; 133: 180-5.
15. Ozbas S, Kocak S, Aydintug S, Cakmak A, Demirkiran MA, Wishart GC. Comparison of subtotal, near total and total thyroidectomy in surgical management of multinodular goiter. Endocr J 2005; 52: 199-205.
16. Jamil M, Amin M. Risk factors for respiratory Complications in Thyroidectomy. J Surg Pak 2002; 7:12-6.
17. Shah SSH, Khan A. Assessment of complications of total thyroidectomy. J Surg Pak 2005; 10: 24-6.
18. Chaudhary IA, Samiullah, Masood R, Mallhi AA. Complications of thyroid surgery: a five year experience at Fauji Foundation Hospital. Rawalpindi. Pak J Surg 2006; 22: 134-7.
19. Bron LP, O'Brien CJ. Total thyroidectomy for clinically benign disease of the thyroid gland. Br J Surg 2004; 91: 569-74.
20. Myssiorek D. Recurrent laryngeal nerve paralysis: anatomy and etiology. Otolaryngol Clin N Am 2004; 37: 25-44.
21. Mc Henry CR. Patient volumes and complications in thyroid surgery. Br J Surg 2002; 89:821-3.
22. Pattou F, Combermale F, Fabre S, Carnaille B, Decoulx M, Wemeau JL et al. Hypocalcaemia following thyroid surgery: incidence and prediction of outcome. World J Surg 1998; 22: 718-24.
23. Delbridge L, Guinea AI, Reeve TS. Total thyroidectomy for bilateral benign multinodular goiter: effect of changing practice. Arch Surg 1999; 134:1389-93.
24. Dholia KR, Shaikh SA. Risks and complications of thyroid surgery: A 10 years experience. J Surg Pak 2007; 12: 19-22.
25. Spear SA, Theler J, Sorensen DM. Complications after the surgical treatment of malignant thyroid disease. Mil Med 2008; 173: 399-402.
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|Author:||Khanzada, Tariq Wahab; Memon, Waseem; Samad, Abdul|
|Publication:||Pakistan Armed Forces Medical Journal|
|Article Type:||Clinical report|
|Date:||Jun 30, 2011|
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