Predicting Calcium Status Post Thyroidectomy with Early Calcium Levels

OBJECTIVE: The study goals were to predict postoperative normocalcemia and hypocalcemia after total thyroidectomy using calcium levels and to assess the value of a standardized protocol in managing the total thyroidectomy patient. STUDY DESIGN: We conducted a prospective study encompassing 68 patients undergoing a total thyroidectomy using a standardized protocol. Blood to measure postoperative calcium levels was drawn at 6, 12, and 20 hours and then twice daily thereafter. Calcium slope was calculated from the 6- and 12-hour serum corrected calcium levels. RESULTS: Logistic regression analysis allowed the comparison of the 6- and 12-hour calcium slope versus proportion of normocalcemic patients postoperatively. A slope of +0.02 had a 97% chance of remaining normocalcemic (p = 0.0007). CONCLUSION: Successful prediction of calcium status post total thyroidectomy can be achieved using the slope of the 6- and 12-hour calcium levels. The risk of developing severe hypocalcemia can also be predicted with these slope values. Implementation of the protocol resulted in a significant reduction in the duration of hospital stay for patients who remain normocalcemic.