PTH Testing Reduces Post‐thyroidectomy Hypocalcemia

Objective To determine if routine rapid intact parathyroid hormone (PTH) testing in the post‐anesthesia care unit (PACU) would reduce post‐thyroidectomy hypocalcemia. Methods Controlled cohort study comparing mean serum calcium and rate of hypocalcemia on postoperative day 1 (POD1) following total or completion thyroidectomy by a single surgeon. The control group consists of 133 subjects undergoing surgery between 2003–2005 prior to availability of rapid PTH testing for whom calcium and vitamin D supplementation was instituted only if patients developed hypocalcemia (calcium<8.0mg/dl) postoperatively. The routine PACU PTH group consists of 169 subjects undergoing surgery between 2006–2007 with routine PACU PTH testing for whom calcium and vitamin D supplementation was instituted for PACU PTH < 15 or subsequent development of hypocalcemia. Results Mean serum calcium corrected for albumin was significantly lower in the control group than the routine PACU PTH group on POD1 (8.2 vs 8.6, p<0.0001). The rate of hypocalcemia on POD1 was higher in the control group than the routine PACU PTH group (35% vs. 14%, p<0.0001). Conclusions Routine PACU PTH testing and early calcium and vitamin D supplementation for patients with hypoparathyroidism significantly reduced the proportion of patients experiencing hypocalcemia following total or completion thyroidectomy.