Prognostic Factors for Definitive Hypoparathyroidism Following Total Thyroidectomy

Introduction and objective: Hypocalcaemia, transient in most cases, is the main complication after thyroid gland surgery with regard to functional impairment of the parathyroid glands or other reversible factors. Sixty-seven patients who underwent thyroidectomy were evaluated to identify potential clinical, pathological and surgical factors that might be predictive for frank hypocalcaemia following total thyroidectomy. Methods: Serum samples were taken preoperatively and postoperatively to measure total calcium levels. Patients' plasma calcium levels were recorded post-operatively along with such factors as age, gender, thyroid function, definitive pathology-based diagnosis, accidental removal and autotransplantation of parathyroid glands, re-intervention to identify risk factors for the development of definitive hypoparathyroidism (DH). All comparisons were made between patients with hypocalcaemia and normal levels of post-operative calcaemia. Results: Transient acute hypocalcaemia was identified in 25 of 67 patients (43.3 %). DH was identified in 8 (11 %) patients. Conclusions: Our study revealed that the only risk factor for DH was a calcium level of less than 7.5 mg/dL within the first 24 hours following surgery; this is a reliable, inexpensive and rapid parameter that is highly predictive of the onset of HD. No statistical significant associations were detected with other factors such as thyroid function, histology, accidental removal or autotransplantation of parathyroid glands, thus it is possible to state that careful manipulation of the parathyroid to preserve the periglandular vascularization is of vital importance to ensure correct post-operative functionality.