Background: Protracted hypocalcemia is the most common complication after parathyroidectomy for secondary hyperparathyroidism. Several parameters have been identified to predict the degree of postoperative hypocalcemia. The purpose of this study was to determine whether there were any factors associated with prolonged hospitalization in these patients.
Methods: A total of 81 consecutive patients with end-stage renal disease and advanced secondary hyperparathyroidism who underwent parathyroidectomy between January 2004 and December 2006 were studied. The postoperative calcium infusion protocol and discharge criteria were standardized. Clinical variables were compared between patients with a shorter or longer postoperative stay.
Results: The mean postoperative hospital stay was 5.6 days. Preoperative alkaline phosphatase levels were significantly higher in patients with a longer stay (p=0.035). In a linear regression model, the postoperative length of stay was moderately but significantly correlated with preoperative alkaline phosphatase levels (R2=0.254; p<0.001). Receiver operating characteristic analysis showed a significant area under the curve (0.678; 95% confidence interval 0.550-0.805; p=0.014). With a cutoff of preoperative alkaline phosphatase levels at 200 IU/L, the sensitivity was 0.57 and the specificity was 0.59 for predicting a prolonged stay.
Conclusions: A high preoperative alkaline phosphatase level is significantly associated with prolonged hospital stay in patients undergoing parathyroidectomy for secondary hyperparathyroidism.