Does the use of a ureteral access sheath improve perioperative outcomes in ureteroscopy? A real-world multi-institutional study.

Retrograde intrarenal surgery (RIRS) is commonly performed with a ureteral access sheath (UAS). Our objective was to evaluate the impact of UAS use in patients undergoing RIRS for renal stones. We conducted a retrospective, multicenter cohort study of all patients who underwent RIRS for kidney stones between January 2017 and December 2018 at six academic medical centers. Patients were stratified according to UAS use. To adjust for baseline differences, we applied inverse probability of treatment weighting (IPTW), a propensity score-based method that balances covariates between groups. A total of 1,177 patients were included: 740 (62.8%) underwent RIRS with a UAS and 437 (37.2%) without. After adjustment, adequate balance was achieved between groups. In IPTW analysis, the stone-free rate (SFR) at three months was comparable between groups (OR = 0.75; 95% CI [0.53-1.08]; p = 0.12). UAS use was associated with longer operative time (estimate = 3.71 min; 95% CI [1.08-7.32]; p = 0.04), lower probability of outpatient procedure (OR = 0.67; 95% CI [0.49-0.91]; p = 0.01), and higher likelihood of postoperative stenting (OR = 3.61; 95% CI [2.72-4.78]; p < 0.001). There were no significant differences in overall complications (OR = 1.16; 95% CI [0.68-1.99]; p = 0.57) or major complications (OR = 1.07; 95% CI [0.45-2.57]; p = 0.86). In this large multicenter retrospective study, UAS use during RIRS was associated with a similar stone-free rate but increased perioperative morbidity. These real-world findings suggest that routine UAS use may not always be necessary, although randomized controlled trials are required to define its role more definitively.