Comparison of a novel one-step percutaneous nephrolithotomy sheath with a standard two-step device.

Objectives: Percutaneous nephrolithotomy (PCNL) is the treatment of choice for large renal calculi. The most widely used access sheath for PCNL involves two steps including placement of a high-pressure balloon catheter (HPBC) followed by advancement of a sheath over the balloon. A novel PCNL balloon/sheath combination (NSS) has been developed that allows for both dilation and sheath placement in a single step. The objective of this study was to compare the safety and efficacy of the NSS to the HPBC in a porcine model.

Methods: Six farm pigs underwent placement of a standard HPBC in one kidney and the NSS on the contralateral side. We obtained access in the upper pole in 2 animals, middle pole in 2 animals, and lower pole in 2 animals. We obtained data on insertion time, difficulty of insertion, estimated blood loss (EBL), ability to visualize the collecting system, and gross and histopathologic analysis.

Results: There was no statistical difference in degree of difficulty in placing the NSS (3 easy, 3 moderate) versus HPBC device (1 easy, 5 moderate; P = 0.07), estimated blood loss (P = 0.10), or the ability to visualize the collecting system (P = 0.32). There was a significantly shorter insertion time in the NSS group compared with the HPBC group (1:37 versus 2:26 minutes, P = 0.04).

Conclusion: This study demonstrates that the NSS is safe and effective in the porcine model. Trials in patients are currently under way.