Postoperative hypocalcemia in patients who did or did not undergo parathyroid autotransplantation during thyroidectomy: A comparative study

Abstract

Background: Permanent hypoparathyroidism is a recognized complication of thyroidectomy. Apart from preservation of parathyroid glands in situ by meticulous dissection, parathyroid autotransplantation (PTHAT) has been performed increasingly to avoid permanent hypoparathyroidism. Methods: From January 1995 to October 1997, PTHAT was performed routinely for devascularized or inadvertently removed glands in 98 (36%) of 271 patients undergoing thyroidectomy. Potential risk factors and the impact of PTHAT on postoperative hypocalcemia were studied. Results: Postoperative hypocalcemia occurred in 40 patients (14.8%), whereas 5 patients (1.8%) had permanent hypocalcemia during a median follow-up of 9 months. The incidence of transient hypocalcemia (n = 35) was higher in patients who underwent PTHAT (21.4%) than in patients who did not undergo PTHAT (8.1%) ( P < .01). Permanent hypocalcemia occurred only in patients who did not undergo PTHAT. None of the 21 patients who had postoperative hypocalcemia after PTHAT had permanent hypoparathyroidism compared with 26% (5/19) of patients who did not undergo PTHAT ( P = .018). When the resected thyroid gland was examined for parathyroid tissue, the incidence of positive identification was higher in patients who did not undergo PTHAT (13%) than in patients who did undergo PTHAT (4%) ( P = .015). Conclusions: Patients with postoperative hypocalcemia after PTHAT have virtually no risk of having permanent hypoparathyroidism. A more careful examination of the resected thyroid tissue can help to identify inadvertently removed parathyroid glands for autotransplantation. (Surgery 1998;124:1081-7.)