EVALUATION AND TREATMENT OF POST-THYROIDECTOMY HYPOCALCEMIA

Transient hypocalcemia is reported to occur postoperatively in approxi mately 7-25% of thyroidectomy patients. Permanent hypocalcemia is seen much less frequently. Although parathyroid insufficiency is most freq uently implicated in post-thyroidectomy hypocalcemia, it appears to be a phenomenon of multifactorial etiology. Preoperative hyperthyroidism causing parathyroid suppression and/or thyrotoxic osteodystrophy shou ld also be considered as causes. Factors that increase the chance of e xtensive dissection such as presence of a large/substernal goiter, thy roid malignancy, or repeat operation increase the likelihood of parath yroid injury and subsequent hypocalcemia. However, an uncomplicated he mithyroidectomy does not exclude the possibility of postoperative hypo calcemia, In the present review, we provide a series of recommendation s for the evaluation and treatment of this complex disorder. In brief, our suggestions are: 1) obtain a serum magnesium, phosphorus, and ion ized calcium level preoperatively and again at 12 and 24 hours after t he procedure, 2) treat a postoperative serum ionized calcium of less t han of 1.12 mMol/L in the asymptomatic patient with oral calcium and v itamin D preparations, 3) treat symptomatic hypocalcemia and/or a seru m ionized calcium of less than 1.0 mMol/L with intravenous calcium. Ca lculations to adjust or correct serum calcium for serum albumin tend t o overestimate the true serum calcium and are not recommended.