Factors affecting hypocalcaemia following total thyroidectomy: a prospective study

After thyroidectomy hypocalcaemia is the most significant complication for clinicians. In this study, we investigated the factors associated with development of hypocalcaemia after thyroidectomy.

We investigated the patients prospectively for age, gender, preoperative diagnosis, hormonal status, operative time, operating surgeon, existence of parathyroid gland injury at the operation, parathyroid gland auto-transplantation, preoperative use of anti-thyroid drugs and amount of bleeding at the operation. After operation in 1 and 2 days, serum calcium and phosphor, and in the 1 day parathyroid hormone values were evaluated. The chi-square test was applied in the analysis of categorical variables. Logistic regression model was used to determine the risk of hypocalcaemia in the univariate analysis.

Hypocalcaemia developed in 47 of 196 patients. Female gender, preoperative diagnosis of thyroid cancer and toxic nodular goitre, <3cm nodule size, parathyroid injury and auto-transplantation and low vitamin D levels were factors found to be associated with hypocalcaemia in the Logistic regression analysis.

The factors associated with hypocalcaemia were defined to be "gender, preoperative diagnosis, parathyroid gland injury, nodule size and vitamin D deficiency", it is a multifactorial problem and it would not be proper to define a few etiological factors.