Predictive factors for post-total thyroidectomy hypocalcaemia

Abstract

Introduction: Post total thyroidectomy hypocalcemia is a frequent and serious complication of thyroid surgery. Predictive Factors of its risk, justifying the prescription of preventive treatment are to be determined.
Aim of the work: to identify the predictive factors of hypocalcemia secondary to total thyroidectomy. Methods: We report a retrospective study involving 260 patients operated with total thyroidectomy at the ENT department of the military hospital of Tunis over a period of 5 years. A statistical study was carried out to find out predictors of hypocalcemia.
Results: Our patients were women in 85% of cases with an average age of 49 years. The incidence of postoperative hypocalcemia was 31.9%. Hypoparathyroidism was definitive in 1.1% of cases. Univariate statistical analysis identified the following factors: presence of cervical swelling at the initial physical exam, gradual onset of mass, thyroid nodule size greater than 4 cm, preoperative calcium level <2.25 mmol/L, one-shot thyroidectomy operating time, histological appearance of thyroiditis and accidental excision of a parathyroid gland. The factors retained in the multivariate study were: gradual onset of mass, nodule size> 4 cm, preoperative calcium level <2.25 mmol/L and histological appearance of thyroiditis.
Conclusion: Post total thyroidectomy hypocalcemia is linked to intrinsic factors of the thyroid, preoperative calcium level, preoperative and intraoperative parathyroid lesions. Its prevention would include: supplementation of patients with hyperthyroidism or with low preoperative calcium levels, systematic identification of the parathyroid glands and their reimplantation in cases of devascularization.