Critical analysis of the intraoperative parathyroid hormone decrease during parathyroidectomy for secondary and tertiary hyperparathyroidism

Abstract

Background: This study aims to determine whether intraoperative parathyroid hormone monitoring helps to predict early surgical outcomes in patients with renal hyperparathyroidism and evaluate the impact on decision making during surgery.

Methods: A prospective study was conducted. Serial samples of the intraoperative parathyroid hormone were collected; 2 of these were taken before the excision, and 2 were taken after the planned parathyroid resection (10 minutes and 15 minutes). We tested the criterion of an intraoperative parathyroid hormone percentage decay ≥80% of the highest value of the basal samples as a predictor of success.

Results: Of the 228 patients, parathyroidectomy achieved success in 92.1%. In patients with secondary hyperparathyroidism, the failure group showed a tendency to stabilize or even increase the intraoperative parathyroid hormone values from the 10-minute measure (577 pg/mL) to the 15-minute measure (535 pg/mL) (P = .903). Conversely, intraoperative parathyroid hormone continued to drop in those with a successful outcome: 245 pg/mL (10 minutes) and 206 pg/mL (15 minutes) (P < .001). The failure group had a significantly lower percentage decay (P < .001) from baseline when compared with the success group. The intraoperative parathyroid hormone influenced the surgical management in up to 7% of the cases. The intraoperative parathyroid hormone dosage method showed an accuracy of 86%, a sensitivity of 88%, and specificity of 67%.

Conclusion: In patients with renal hyperparathyroidism undergoing parathyroidectomy, the use of intraoperative parathyroid hormone may help to predict an early therapeutic outcome with high sensitivity and accuracy by indicating the operation's success when there is an 80% reduction of baseline intraoperative parathyroid hormone 15 minutes after removal of the enlarged glands, an associated continuous decrease in serum intraoperative parathyroid hormone levels between 10 and 15 minutes, and achievement of plasma target values <500 pg/mL.