Postoperative parathyroid hormone level as a predictor of post-thyroidectomy hypocalcemia

Objectives: To evaluate levels of parathyroid hormone following total thyroidectomy in order to ascertain its ability to predict postoperative hypocalcemia. To establish standardized criteria permitting the safe discharge of total thyroidectomy patients within 13 hours of surgery. Methods: This is a prospective study in which parathyroid hormone levels were tested in 54 consecutive patients who underwent total thyroidectomy. Levels were measured postoperatively at 6, 12, and 20 hours. Corrected calcium levels were also measured at 6, 12, and 20 hours in accordance with the preexisting protocol. Results: Statistical analysis demonstrates that patients with corrected calcium levels greater than or equal to 2.14 mmol/L and parathyroid hormone levels greater than or equal to 28 ng/L at 12 hours post-thyroidectomy can be discharged without further need for calcium monitoring. The analysis also demonstrates that patients with 12-hour parathyroid hormone levels less than or equal to 20 ng/L are at significant risk of developing hypocalcemia. Conclusion: Parathyroid hormone levels in conjunction with corrected calcium values are accurate predictors of the calcium trends of post-thyroidectomy patients. Implementation of this protocol can result in shorter hospital stays for the majority of post-thyroidectomy patients, which can translate into substantial cost savings for the health care system.