Abstract
Objectives:
Hypocalcemia linked to a diminished circulating intact parathormone (iPTH) is the most common complication after total thyroidectomy. The outcome of our single-center prospective study is to determine the interest of iPTH as a predictor of post-thyroidectomy hypocalcemia.
Methods:
One hundred eight patients who underwent total thyroidectomy were included. Blood samples (iPTH, calcium, and albumin) were performed at different times: preoperatively (H0), after removal of the gland (Hdrop), 6 hours (H6) after surgery, and one day (D1) after surgery. A measurement of calcium and albumin was performed on the second postoperative day (D2). The area under the receiver-operating characteristic (ROC) curve (AUC) was used to determine the best cutoff value and predictability of iPTH for hypocalcemia in terms of absolute value (ng/L), decrease in the slope (ng/L), and decline (%) between 2 times.
Results:
Seven patients were excluded. Of the remaining 101 patients, 39 had hypocalcemia (38.6%). At H6, an iPTH absolute value less than 14.35 ng/L (Se = 0.706; Sp = 0.917) and a decline from the preoperative time of more than 59.5% (Se = 0.850; Sp = 0.820) were predictive of hypocalcemia. Other absolute values, decrease in the slope, and decline between preoperative and postoperative values are less efficient.
Conclusions:
The iPTH 6 hours after total thyroidectomy is predictive of hypocalcemia. It could be used to identify patients not at risk of hypocalcemia, and earlier discharge could be considered.