Predictors of hyperkalemia after total parathyroidectomy in patients with drug-refractory secondary hyperparathyroidism.

Background: The purpose of this retrospective study was to explore the primary possible risk factors for the development of postoperative hyperkalemia after total parathyroidectomy with autotransplantation (TPTX + AT) in patients with drug-refractory secondary hyperparathyroidism (SHPT). Methods: The clinical data of 149 patients receiving maintenance dialysis for drug-refractory SHPT, who underwent TPTX + AT, were reviewed and analyzed. Demographic data, dialysis status, and laboratory test indices were collected from enrolled patients. According to the postoperative serum potassium level >5.3 mmol/L or not, they were divided into hyperkalemia group and non-hyperkalemia group. The differences in general clinical data and laboratory indicators between the two groups were compared; logistic regression analysis was performed to analyze the risk factors affecting the development of postoperative hyperkalemia in patients; receiver operating characteristic (ROC) subject workup curves were analyzed for the threshold values of postoperative hyperkalemia. Results: Of the 149 participants, 25 (16.78%) developed postoperative hyperkalemia after TPTX + AT. Univariate analysis suggested that dialysis duration, SHPT duration, dialysis modality, and preoperative alkaline phosphatase, blood potassium, and blood calcium levels were independently associated with the development of hyperkalemia after TPTX + AT. Univariate logistic analysis suggested that dialysis duration [odds ratio (OR) 1.18, 95% confidence interval (CI): 1.03, 1.35, P=0.014], preoperative blood potassium (OR 4.95, 95% CI: 2.05, 11.96, P<0.001), and preoperative blood calcium (OR 16.17, 95% CI: 1.36, 191.58, P=0.027) were 3 factors that predicted hyperkalemia after TPTX + AT. According to ROC curve analysis, the optimal cutoff point for dialysis duration was 8.5 years, the optimal cutoff level for preoperative blood potassium was 4.57 mmol/L, and the optimal cutoff level for preoperative blood calcium was 2.31 mmol/L. Of these 3 factors, preoperative blood potassium had a more balanced sensitivity, specificity, and optimal diagnostic efficacy. Conclusions: Patients with drug-refractory SHPT are prone to hyperkalemia after TPTX + AT. Duration of dialysis and preoperative blood potassium and blood calcium levels can help predict the development of postoperative hyperkalemia.