The influence of intraoperative parathyroid hormone monitoring on the surgical management of hyperparathyroidism.

OBJECTIVE

To examine the role of intraoperative rapid parathyroid hormone (PTH) monitoring in the surgical management of hyperparathyroidism.

DESIGN

Thirty-eight-month retrospective review.

SETTING

Tertiary care academic medical center.

PATIENTS

One hundred consecutive patients undergoing surgery for primary hyperparathyroidism.

INTERVENTION

All patients underwent preoperative technetium Tc 99m sestamibi scan localization and intraoperative blood PTH monitoring by means of a rapid (12-minute) immunochemiluminometric assay.

MAIN OUTCOME MEASURES

The influence of intraoperative PTH levels on extent of surgical dissection and achievement of postoperative normocalcemia.

RESULTS

Intraoperative PTH levels dropped an average of 64%, 75%, and 83% at 5, 10, and 20 minutes, respectively, after excision of all hyperfunctioning parathyroid tissue. A PTH decrease of 46% or more at 10 minutes and 59% or more at 20 minutes after excision of hyperfunctioning tissue was predictive of postoperative normocalcemia. In 79 patients (79%), the sestamibi scan provided accurate preoperative localization; all but 1 of these patients were treated successfully, most often with a limited, gland-specific dissection. In 24 patients with inaccurate, negative, or misleading preoperative sestamibi scans, 23 (96%) were treated successfully with the use of the intraoperative PTH assay.

CONCLUSIONS

The rapid intraoperative PTH assay accurately predicts postoperative success in patients with primary hyperparathyroidism. The rapid PTH assay allows for greater confidence in performing limited dissections in well-localized uniglandular disease. In cases of inaccurate preoperative localization, the rapid PTH assay directly affects surgical decision making and provides greater confidence in determining when surgical success has been achieved.