Post-thyroidectomy Hypocalcemia in High- Risk Patients Following Total Thyroidectomy

ABSTRACT

PURPOSE: Parathyroid injury is the major cause of post-thyroidectomy hypocalcemia. This prospective study aimed to define the relation between the preservation status of the parathyroid glands and post-thyroidectomy hypocalcemia as well as to determine whether the number of preserved parathyroid glands could be a guideline for the management of post-thyroidectomy hypocalcemia. METHODS: We analyzed a total of 76 cases of total thyroidectomy due to malignancy were analysed. Parathyroid gland status at the end of thyroidectomy was classified as preserved intact, discolored (color change or equivocal viability), or autotransplanted. Patients were grouped according to the number of intact preserved parathyroid glands into group 1 (more than two), group 2 (one), or group 3 (zero). The total and ionized serum calcium levels of each group were monitored for three days after surgery. RESULTS: The number of intact preserved parathyroid glands was not found to be closely related to serum calcium level, although ionized serum calcium level was significantly lower in group 1 than group 2 (P<0.001). Hypocalcemia was not found in group 1. Hypocalcemia was found in 31% (10/32) of group 2. Among the 32 patients of group 2, all 4 parathyroid gland were identified in 9 patients and 4 patients were shown to be hypocalcemic. Therefore, the incidence of hypocalcemia for patients in whom only one intact parathyroid was preserved and all 4 parathyroid were indentified was 44% (4/9). Hypocalcemia was transient in all patients. CONCLUSION: The parathyroid glands should be preserved as much as possible to minimize post-thyroidectomy hypocalcemia. The number of intact preserved parathyroid glands can be a good guideline for predicting post-thyroidectomy hypocalcemia and proper care management.