Predictive factors for percutaneous nephrolithotomy outcomes in neurogenic bladder population

Abstract

Purpose: To review experience performing percutaneous nephrolithotomy (PCNL) on patients with neurogenic bladder, evaluating predictors for increased length of stay (LOS), intensive care unit (ICU) stay, stone-free rate, and number of procedures and outcomes measures between spinal cord injury (SCI) and spina bifida (SB) patients.

Patients and methods: We retrospectively reviewed our PCNLs from January 1, 2002 to December 31, 2009 and identified 47 patients. Data collected included LOS, ICU stay, stone-free rate, complications, and total procedures.

Results: A total of 66 PCNLs were performed on 47 patients. The mean LOS was 5.3 days, and nine patients needed ICU stay (mean 13.9 d). Initial stone-free rate was 60.6%, and final stone-free rate was 69.7%. Multiple access was associated with increased LOS (P=0.01), ICU stay (P<0.01), transfusion (P<0.01), and pulmonary complications (P=0.03). Upper-pole access was associated with decreased initial stone-free rate (P=0.04). Midpolar access predicted increased final stone-free rate (P=0.04). Mean stone size was 3.31 cm and was predictive of an increased number of procedures (P=0.04). Larger stone size was also predictive of decreased initial stone-free rate (P=0.03) and final stone-free rate (P=0.05). There were no statistically significant differences between SCI and SB patients in terms of outcomes.

Conclusions: Increasing stone size and multiple access were predictors of adverse outcomes, and location of access affected stone-free status. We found no differences in outcomes between SB and SCI patients. To our knowledge, this is the largest series reported regarding PCNLs in this patient population.