Impact of thyroid volume on serum ionized calcium and PTH levels after total thyroidectomy

This is the authors' abstract. We don't add key points for this paper.

BACKGROUND: The relationship between thyroid gland volume and hypoparathyroidism after total thyroidectomy remains controversial. OBJECTIVE: To evaluate thyroid gland mass as a risk factor for hypoparathyroidism after total thyroidectomy. DESIGN AND SETTING: A Retrospective cross-sectional observational study was conducted at Centro Universitário Lusíada (UNILUS), Santos/SP, Brazil. METHODS: Patients undergoing total thyroidectomy between January 2022 and September 2023 were retrospectively evaluated for serum levels of ionized calcium and ultrasensitive parathyroid hormone (PTH), measured preoperatively and 30-60 days postoperatively, and thyroid mass, obtained by weighing the specimen. RESULTS: A total of 174 patients were evaluated, with a predominance of women (89.7%), a median age of 50.5 years, and a median goiter volume of 36.3 mL. A reduction in both PTH and ionized calcium levels was observed in the postoperative period compared with the preoperative period (P < 0.05). No significant changes were observed in PTH levels and volume (P = 0.481). For calcium, there was a tendency towards an association between volume measurements and its change between the pre- and postoperative periods, which was marginally significant (P = 0.051). CONCLUSION: There was a marginal association between volume and changes in pre- and postoperative ionized calcium levels, but no significant association with pre- and postoperative PTH measurements.

Thyroid volume lacks significant PTH association post-thyroidectomy; leaves open need for prospective studies on hypoparathyroidism risk.