Incidence and Risk Factors of Postoperative Hypocalcaemia Following Subtotal Thyroidectomy
DOI:
https://doi.org/10.54112/bcsrj.v7i5.2292Keywords:
Hypocalcemia; Thyroidectomy; Subtotal Thyroidectomy; Parathyroid Hormone; Vitamin D Deficiency.Abstract
Postoperative hypocalcaemia is a common metabolic complication after thyroid surgery and may result from transient parathyroid dysfunction, parathyroid gland manipulation, or impaired vascular supply. Identification of high-risk patients may help improve postoperative monitoring and early management. Objective: To determine the incidence and risk factors of postoperative hypocalcaemia among patients undergoing subtotal thyroidectomy. Methods: This observational study included 70 patients who underwent subtotal thyroidectomy at a Shaikh Zayed Hospital Lahore from July to December 2025. Demographic, clinical, biochemical, and operative data were recorded. Postoperative biochemical hypocalcaemia was defined as corrected serum calcium <8.0 mg/dL within 48 hours after surgery. Symptomatic hypocalcaemia was defined as biochemical hypocalcaemia with clinical symptoms requiring calcium supplementation. Data were analyzed using SPSS version 26. Univariate analysis and multivariable logistic regression were performed to identify independent predictors of postoperative hypocalcaemia. Results: The mean age of patients was 42.9 ± 12.1 years, and 53 patients (75.7%) were female. Postoperative biochemical hypocalcaemia occurred in 16 patients (22.9%), while symptomatic hypocalcaemia was observed in 7 patients (10.0%). No patient developed persistent hypocalcaemia at six months. Patients who developed hypocalcaemia had significantly lower preoperative corrected calcium, lower vitamin D levels, lower 24-hour postoperative calcium, lower 48-hour postoperative calcium, and lower 24-hour parathyroid hormone levels compared with normocalcaemic patients. On multivariable logistic regression, vitamin D deficiency, preoperative corrected calcium <9.0 mg/dL, operative duration >90 minutes, and visualization of fewer than two parathyroid glands were independent predictors of postoperative hypocalcaemia. Conclusion: Postoperative hypocalcaemia occurred in nearly one-fourth of patients following subtotal thyroidectomy, but most cases were transient and clinically manageable. Vitamin D deficiency, low preoperative calcium, prolonged operative duration, and limited parathyroid visualization were significant independent predictors. Preoperative biochemical assessment, correction of vitamin D deficiency, careful parathyroid preservation, and structured postoperative calcium monitoring may reduce clinically significant hypocalcaemia.
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Copyright (c) 2026 Qastoona Seemab, Muhammad Imran Anwar, Muhammad Afzaal, Muhammad Usama Khan, Muhammad Usman, Talha Saeed
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