Risk factors of hypocalcemia after thyroid surgery

Background Hypocalcemia is a common complication that may be encountered after thyroid surgery. This study was conducted to evaluate the risk factors for postoperative hypocalcemia after thyroid operations. Patients and methods We retrospectively reviewed the data of 200 consecutive cases that underwent thyroidectomy at our department between January 2017 and December 2019. The following data were collected; age, sex, systemic comorbidities, disease nature, preoperative calcium levels, operation type, need for neck lymph node dissection, operative time, surgeon experience, and postoperative calcium and parathyroid hormone levels. Results Temporary hypocalcemia was encountered in 36 (18%) cases. The hypocalcemic group showed higher female prevalence (P=0.045), more toxic cases, more malignant cases (P=0.005), more total thyroidectomy operations (P=0.039), lower preoperative calcium levels (0.015), more low experienced surgeons (P=0.021), and lower postoperative parathyroid hormone levels (P<0.001). Conclusion Toxic goiter, malignancy, total thyroidectomy, level D surgical experience, and preoperative calcium levels are independent predictors for postoperative hypocalcemia. Moreover, female sex, lymph node dissection, and postoperative low parathyroid hormone levels are risk factors for that complication.