To investigate whether a smaller tract size for percutaneous nephrolithotomy (PCNL) may result in fewer complications including blood loss, while retaining similar stone-free rates and operative time, utilizing a modern approach without postoperative nephrostomy tube.

We performed a randomized controlled trial at five participating EDGE institutions in North America. Patients were randomized to receive 17.5Fr miniature tract vs 30Fr standard sized tract for PCNL without postoperative nephrostomy tubes.

Demographic variables were similar. Mean decrease in hemoglobin was 1.84 g/dL for standard and 1.67 g/dL for mini ( p  = .654), with similar blood transfusion rates. Differences in stone-free rates (71% standard vs 77% mini) emergency room visits (13% vs 23%), additional procedural interventions (9% vs 3%), and intrarenal pressure measurements were not statistically significant. Mean pain scores in the post-anesthesia care unit were low in both groups (2.53 standard vs 1.88 mini, p  = .440). Clavien-Dindo complication rates were 14% for standard and 15% for mini ( p  = .593). There were 11% and 5% of patients in standard and mini groups who experienced at least 2/4 systemic inflammatory response syndrome (SIRS) criteria ( p  = .370).

Results from a multi-institutional randomized controlled trial evaluating mini versus standard PCNL without postoperative nephrostomy tubes indicate no statistically significant differences in intraoperative, postoperative, or stone-free outcomes. Surgeons should be empowered to utilize the PCNL tract size that best meets the needs of their patient, institution, and practice.