Editorial Comment for Kadlec et al.

P ercutaneous nephrolithotomy (PCNL) remains the gold standard for treatment of patients with large (>2.0 cm) and branching renal calculi. Improvements in technique and hospital care have led to excellent outcomes with low morbidity and short hospital stay as reported in a recent contemporary series at a high-volume center. ¹ At our own center, with increasing pressure from insurance providers to limit inpatient stays, the majority of PCNLs are performed as 23-hour observation procedures with the goal of having the patient discharged before noon on postoperative day one.

In the current study, the authors attempt to define complication rates for PCNL as they relate to surgical volume using the 2010 Healthcare Cost and Utilization Project Nationwide Inpatient Sample. Although case volume did correlate with short length of stay (LOS), somewhat surprisingly, complication rates were similar regardless of volume. As noted by the authors, “high-volume” centers in this study performed 11 to 33 PCNLs per year and “very high-volume” was 33+ (volume was divided by quartiles). In comparison, in a Clinical Research Office of the Endourological Society database study that evaluated complications after PCNL, the authors reported that not only were complications lower in high-volume centers, but also stone-free rates were higher and LOS shorter. The median case volume was 77 cases per year, substantially more than the current study. ² It is possible in the current study that the overall lack of true high-volume centers has resulted in a data set that is skewed toward lower volume centers and may help to explain why differences between low- and high-volume centers were not identified.