Combining Early Postoperative Parathyroid Hormone and Serum Calcium Levels Allows for an Efficacious Selective Post‐thyroidectomy Supplementation Treatment

Abstract

Optimal treatment protocol to prevent symptomatic hypocalcemia following total thyroidectomy is still matter of debate. We prospectively evaluated the efficacy of a selective supplementation protocol based on both early postoperative intact parathyroid hormone (iPTH) and serum calcium levels. Two hundred thirty consecutive patients were divided in three different groups of treatment according to iPTH levels 4 h after total thyroidectomy (4 h-iPTH) and serum calcium levels in the first postoperative day (1PO-Ca): group A (4 h-iPTH > 10 pg/ml, 1PO-Ca ≥ 8.5 mg/dl), no treatment; group B (4 h-iPTH > 10 pg/ml, 1PO-Ca < 8.5 mg/dl), oral calcium (OC) 3 g per day; and group C (4 h-iPTH ≤ 10 pg/ml), OC 3 g + calcitriol (VD) 1 μg per day. Development of biochemical and/or symptomatic hypocalcemia was evaluated. Fifty-nine patients (25.6%) had subnormal 4 h-iPTH levels (≤10 pg/ml) (group C). Among patients with normal 4 h-iPTH levels, 25 (10.9%) had subnormal 1PO-Ca (<8.5 mg/dl) (group B). The remaining 146 patients (63.5%) had normal 4 h-iPTH and 1PO-Ca levels (group A). One patient in group A, 2 in group B, and 18 in group C developed biochemical hypocalcemia. Only one patient in group C experienced major symptoms. Treatment was discontinued within 1 month in all the patients in group B. At a mean follow-up of 303 days, five patients in group C were still under supplementation treatment. The proposed supplementation protocol seems efficacious in preventing symptomatic hypocalcemia. It could allow a safe and early discharge of most patients, thus avoiding the constraints and the costs of routine supplementation.