Comparison of two different minimally invasive percutaneous nephrostomy sheaths for the treatment of staghorn stones.

OBJECTIVE: To compare the safety and effectiveness of using a conventional nephrostomy sheath (NS) vs using a new NS with suction and evacuation functions in minimally invasive percutaneous nephrolithotomy (MPCNL) for the treatment of staghorn stones. PATIENTS AND METHODS: A prospective and randomised study of 60 patients with staghorn stones randomly assigned into two groups of 30 patients. One group underwent MPCNL using conventional NS, whereas the other group underwent MPCNL with suction-evacuation NS (SENS). Patient demographics, stone characteristics, intraoperative data, perioperative data, and surgical results were collected and analysed. RESULTS: The patient demographics and stone characteristics were similar amongst the two groups. The SENS group had a significantly lower peak and a significantly lower average renal pelvic pressure (RPP) throughout the procedure. The SENS group was more efficient for stone removal and had a much shorter stone treatment time, a lesser use of the stone extractor, and ultimately a higher stone-free rate (SFR). The effects of a lower RPP and shorter stone treatment time translated into less severe postoperative complications as measured per modified Clavien grade. CONCLUSION: Using SENS in MPCNL for the treatment of staghorn stones has the advantages of lower RPP, increased effectiveness in stone retrieval, decreased surgery related complications, and an improved SFR.