Usefulness of pre- and post-operative calcium and Vitamin D supplementation in prevention of hypocalcemia after total thyroidectomy: A randomized controlled trial

BACKGROUND Total thyroidectomy (TT) is a commonly performed surgery and postoperative hypocalcemia is a major detriment to early discharge. The aim of this randomized controlled trial was to ascertain the usefulness of routine pre- and post-operative calcium and Vitamin D supplementation in prevention of hypocalcemia after TT. MATERIALS AND METHODS Sixty consecutive patients who underwent total or near TT from February 2013 to August 2014 were included in the study. They were randomly divided into two groups - Group 1 received oral calcium (500 mg every 6 h) and Vitamin D (calcitriol 0.25 mcg every 6 h) 7 days before and 7 days after the surgery; and Group 2 did not receive supplementation. Symptoms and signs of hypocalcemia were monitored. Calcium profile was measured pre- and post-operatively at 6, 12, 24, 48, 72 h, and on 30th day. Hypocalcemia after surgery was either symptomatic or laboratory documented. Serum calcium level ≤ 8.5 mg/dl was considered as laboratory hypocalcemia. RESULTS Twelve patients from Group 2, and 3 patients from Group 1 developed symptomatic hypocalcemia (P < 0.01). Laboratory hypocalcemia within postoperative 24 h was comparable between two groups, but more patients of Group 2 compared to Group 1 developed hypocalcemia at 48 h (6 and 13, respectively; P = 0.04) and at 72 h after surgery (5 and 14, respectively; P = 0.01). Twenty-four hours postoperative serum calcium level was significantly associated with grade of goiter, preoperative calcium, and nature of thyroid disease (benign or malignant). On multiple linear regression analysis, preoperative serum calcium was only independent variable significantly associated with development of 24 h post-TT hypocalcemia. CONCLUSION Routine pre- and post-TT calcium and Vitamin D supplementation can significantly reduce postoperative hypocalcemia.