Retrograde flexible nephrolithotripsy using a navigation aspiration sheath for renal stones measuring > 2 cm

Introduction. The use of an aspiration sheath has expanded the surgical armamentarium for the management of urolithiasis. Nevertheless, comparative data on its efficacy and safety in the treatment of large renal stones (> 2 cm) during retrograde flexible nephrolithotripsy remain limited.

Objective. To assess the advantages of a ureteral sheath with active aspiration over a conventional sheath with respect to key clinical outcomes during flexible ureteroscopy in patients with urolithiasis.

Materials & methods. We performed a retro-prospective analysis of outcomes after flexible ureteroscopy in 108 patients with renal stones measuring 2 to 3 cm. A ureteral sheath was used as an adjunct in all cases. Two approaches were compared: use of a sheath without active aspiration (retrospective group, n = 54) and use of a sheath with active aspiration (prospective group, n = 54). The assessed outcomes included operative time, stone-free rate (SFR), severity of postoperative pain, blood loss, renal function parameters, the spectrum and severity of complications, length of hospital stay, and the rate of repeat procedures.

Results. The use of a ureteral sheath with active aspiration during flexible ureteroscopy was associated with a significant reduction in operative time: mean duration was 64.1 ± 5.7 min compared with 81.1 ± 8.6 min with a conventional sheath (p = 0.001). The stone-free rate in the active aspiration group reached 90.7%, exceeding that of the conventional sheath group (77.8%) by 12.9% (p = 0.001). The rate of postoperative complications was significantly lower in the active aspiration group, at 7.4% vs 16.7% in the control group (p = 0.001), while infectious complications were more frequent in the group without active aspiration (11.1%).

Conclusion. The use of a ureteral sheath with active aspiration during flexible ureteroscopy shortens operative time, increases the stone-free rate, and reduces the incidence of postoperative complications, including infectious events.

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