When should we stop operating? Multicenter analysis of operative time, outcomes, and complications in ureteroscopy with flexible navigable suction access sheath (FANS) by EAU Endourology

Flexible ureteroscopy (FURS) is increasingly used for renal stones, with prolonged operative time (OT) linked to complications. Flexible and Navigable Suction Access Sheaths (FANS) may allow longer OTs due to better intrarenal pressure control. We aimed to evaluate risk factors for prolonged OT and associated outcomes using FANS. A retrospective analysis of a prospective multicentric database across 25 centres included 556 adults undergoing FURS with FANS between August 2023 and January 2024. Patients were stratified into three groups by OT: <60 min(group 1), 60–89 min(group 2), and ≥ 90 min(group 3). Multivariable linear regression assessed predictors of prolonged OT, and outcomes including complications, stone-free rate (SFR), and hospital stay were analysed between the groups. Longer OT correlated with larger stone volume, complex stone locations (multiple/lower pole), absence of pre-stenting, smaller access sheath (10/12 Fr), and low-power Ho: YAG laser use (p < 0.05). Use of TFL or high-power Ho: YAG reduced OT. Despite longer procedures, there was no significant increase in postoperative infections or sepsis in groups 2 and 3. However, overall SFR was lower with increasing OT (Group 1: 96.9%, Group 2: 93.5%, Group 3: 82.4%, p < 0.001), and same day discharges were lower in groups 2 and 3. Longer OTs during FURS with FANS are driven by stone complexity and procedural factors but do not increase postoperative infectious complications. The traditional 90-minute limit may not apply when using FANS, warranting re-evaluation of current OT thresholds.