Citation Information :
Shanmugam S, Balakrishnan S. Intraoperative Parathyroid Hormone Levels: A Predictor of Postoperative Hypocalcemia in Total Thyroidectomy for Thyroid Cancer Patients. 2023; 18 (2):49-52.
Background: During parathyroidectomy, intraoperative parathyroid hormone (ioPTH) levels are commonly utilized as a sign of parathyroid gland function. However, they are not commonly utilized in thyroid cancer surgery. The ability to successfully identify individuals at risk for postoperative hypocalcemia may reduce morbidity by initiating early replacement treatment and identifying patients who can be safely discharged from the hospital.
Aims and objective: To determine whether the use of ioPTH assay can accurately predict postoperative calcium levels following total or completion thyroidectomy in thyroid cancer patients.
Materials and methods: We analyzed the ioPTH of all patients who underwent total thyroidectomy with or without neck dissection in our institution for thyroid cancer and neoplasm. In postoperative period, serum calcium was measured in those patients on POD 1 and POD 6. The ioPTH levels are correlated with postoperative calcium levels.
Results: In our study, we included 35 patients who underwent total thyroidectomy in our institution. Postoperative histopathological examination revealed 30 patients had papillary carcinoma, three had follicular carcinoma, one had medullary carcinoma, and one without any malignancy. Out of 35 patients, 14 patients showed biochemical hypocalcemia in immediate postoperative period. Among these 14 patients, 10 patients had clinical signs/symptoms of hypocalcemia. Out of these 14 patients, 12 patients had ioPTH levels less than 10 pg/mL which shows a positive correlation between intraoperative parathyroid levels and immediate postoperative calcium levels.
Conclusion: Intraoperative PTH monitoring may be a quick and effective tool for identifying those patients who are at risk for postoperative hypocalcemia and a useful tool in identifying thyroid cancer patients who will not require postoperative calcium supplementation following total or completion thyroidectomy.
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