Ultrasonic scalpel with knot tying protects parathyroid function for total thyroidectomy with central neck dissection

Gland Surg. 2020 Apr;9(2):192-199. doi: 10.21037/gs.2020.01.12.

Abstract

Background: Hypoparathyroidism might be due to collateral thermal injury induced by harmonic scalpel (HS) after total thyroidectomy (TT) with central neck dissection (CND). The current study aimed to evaluate whether a clamp and tie (CAT) technique used to preserve parathyroid glands in situ could reduce damage to parathyroid function in HS patients undergoing TT plus unilateral or bilateral CND.

Methods: Medical records of 537 HS-operated patients with papillary thyroid carcinoma (PTC) undergoing TT plus unilateral or bilateral CND were retrospectively evaluated. Patients were divided into HS and HS-CAT groups based on whether the CAT techniques were used near parathyroid glands. Patients' characteristics such as age, sex, tumour size, operative time, pre- and post-operative levels of parathyroid hormone (PTH) and complications were analysed.

Results: For patients undergoing TT plus unilateral CND, operative time was significantly shorter (P<0.001), but there were significantly higher incidences of transient hypoparathyroidism (P=0.002) on postoperative day 1 and incidental parathyroidectomy (P=0.036) in the HS group. There was no significant difference in permanent hypoparathyroidism. For patients undergoing TT plus bilateral CND, a significantly shorter operative time and sharper postoperative PTH decline was found in the HS group (P=0.029). However, there were no significant differences regarding incidences of incidental parathyroidectomy, transient or permanent hypoparathyroidism.

Conclusions: The CAT technique applied near parathyroid glands was a practical surgical application for decreasing the incidence of postoperative transient hypoparathyroidism for TT plus unilateral CND.

Keywords: Cold knife; harmonic scalpel (HS); hypoparathyroidism; knot tying; total thyroidectomy (TT).