Post thyroidectomy hypocalcaemia - an audit of 100 cases

Abstract

Purpose of our study is to compare the incidence of hypocalcaemia after total, near total or subtotal thyroidectomy for benign multinodular goitre. One hundred consecutive thyroidectomies performed for euthyroid benign multinodular goitre at West surgical unit, Mayo hospital, Lahore Pakistan, were included in the study. Mean age of patients was 33 (range 14 to 60) years. Preoperative serum calcium level ranged from 7.7 to 10.0 with an average of 8.8mg/dl. 34 patients had total thyroidectomy, 31 had near total thyroidectomy, 28 had subtotal thyroidectomy and 7 had lobectomy & isthmusectomy. Consultants performed 46 thyroidectomies, while senior registrars and residents performed 52 and 2 thyroidectomies respectively. 28 patients developed clinical features of hypocalcaemia.8 out of 31 patients who had near total thyroidectomy developed hypocalcaemia (25.8%). Out of 34 total thyroidectomies, 11 patients had hypocalcaemia (32.3%). In 28 patients who had subtotal thyroidectomy, 7 developed hypocalcaemia (25%) . 2 out of 7 lobectomy & isthmusectomy patients also required treatment for hypocalcaemia (28.5%). Hypocalcaemia developed within 48 hours of surgery in 53% of our patients. Incidence of hypocalcaemia among patients operated by consultants was 23.9 % (11 out of 46), while among patients operated by senior registrars and residents 17 out of 54 developed hypocalcaemia i.e. 31.5%. Average postoperative duration of hospital stay was 5.42 days in hypocalcaemic patients (range 2-17 days) and it was 2.77 days in normocalcaemic patients (range 1-6 days). We conclude that post thyroidectomy hypocalcaemia is a complication with significant morbidity. The incidence of this complication can be reduced by meticulous surgical technique with special emphasis on haemostasis. Identification and preservation of well vascularized parathyroid glands must be attempted in every thyroidectomy.