Percutaneous nephrostolithotomy: Predictors of length of stay

Purpose: Percutaneous nephrostolithotomy (PNL) is commonly used to treat patients with complex renal calculi. A goal at our medical center is to discharge patients home less than 24 hours after PNL. We performed a study to determine factors that caused patients to be hospitalized longer than this period. Material and Methods: The available hospital records and office charts of 133 consecutive patients undergoing initial PNL at our institution between January 1, 1999 and December 31, 2000 were reviewed. All PNL procedures were performed by one of us using a (DGA) 1-stage technique. Mean patient age was 52 years (range 25 to 84). Of the subjects 85 were male and 48 were female. Results: A total of 91 patients (68%) were discharged home less than 24 hours after surgery. The overall stone-free rate was 91%. Mean length of stay in the entire group was 1.97 days. Mean length of stay in those hospitalized longer than 24 hours was 4.12 days. Mean operative time, including time to obtain access, was 188.6 minutes. Multivariate analysis demonstrated that neurogenic bladder, endocrine comorbidity and perioperative complications were factors associated with a length of stay of greater than 24 hours. Univariate analysis demonstrated that preoperative urinary tract infection and infection related calculi were also associated with a length of stay of greater than 24 hours. Conclusions: The majority of patients undergoing PNL can be discharged home less than 24 hours after surgery. Patients with neurogenic bladder, those with endocrine comorbidity, those who sustain significant perioperative complications and those harboring stones associated with urinary tract infection or preoperative urinary tract infection are more likely to require longer hospitalization.