Efficacy and safety of flexible ureteroscopy assisted by a flexible-tip negative pressure suction sheath for 2-4 cm renal calculi.

OBJECTIVE: To investigate the efficacy and safety of flexible ureteroscopy assisted by a flexible-tip negative-pressure suction sheath for the treatment of 2-4 cm renal calculi. METHODS: We retrospectively analyzed clinical data from 103 patients with 2-4 cm renal calculi who underwent flexible ureteroscopic holmium laser lithotripsy. Patients were divided into a flexible-tip suction sheath group (n=52) and a conventional sheath group (n=51) according to the type of ureteral access sheath used during surgery. Perioperative findings and surgical complications were compared between the two groups. RESULTS: The stone-free rate was significantly higher in the flexible-tip suction sheath group (92.31%) than in the conventional sheath group (76.47%), and hospital stay was significantly shorter (both P < 0.05). The incidences of postoperative fever and steinstrasse in the flexible-tip suction sheath group were 3.85% and 1.92%, respectively, which were significantly lower than the 17.65% and 15.67% observed in the conventional sheath group (both P < 0.05). Postoperatively, serum levels of TNF-α, IL-1β, IL-6, CRP, cortisol, norepinephrine, and adrenocorticotropic hormone increased in both groups; however, the magnitude of elevation was significantly smaller in the flexible-tip suction sheath group (all P < 0.05). In addition, postoperative levels of serum creatinine, cystatin C, blood urea nitrogen, and neutrophil gelatinase-associated lipocalin, as well as 6-month postoperative quality-of-life scores, were significantly better in the flexible-tip suction sheath group than in the conventional sheath group (all P < 0.05). CONCLUSION: The application of flexible-tip negative-pressure suction sheath-assisted flexible ureteroscopy in patients with 2-4 cm renal calculi was associated with a higher stone-free rate, reduced incidences of specific postoperative complications, and more favorable short-term recovery outcome. This suggests its clinical value. Nevertheless, prospective randomized controlled trials are warranted for further validation.