Preoperative ureteral rest and outcomes of robot-assisted upper urinary tract reconstruction: a systematic review and meta-analysis.

To evaluate whether a preoperative period of ureteral rest, defined as the absence of any indwelling stent crossing the diseased or anastomotic segment (irrespective of whether upper-tract drainage is maintained by a percutaneous nephrostomy), is associated with improved surgical success and perioperative outcomes after robot-assisted upper urinary tract reconstruction, comprising ureteral reconstruction and pyeloplasty for ureteropelvic junction obstruction. We searched PubMed/MEDLINE, Embase, Web of Science Core Collection and the Cochrane Library from inception to 31 July 2026, and included English-language studies that compared ureteral rest with immediate reconstruction. Studies without a no-rest comparator or without the key outcomes were excluded. Random-effects meta-analyses were performed in Review Manager 5.3 and R, using odds ratios (OR) or risk ratios (RR) for dichotomous outcomes and mean differences (MD) for continuous outcomes. The review was registered with PROSPERO (registration number CRD420261504719). Five retrospective comparative studies including 707 patients (478 managed with preoperative ureteral rest and 229 managed without) were analysed. Preoperative ureteral rest was associated with a higher pooled surgical success rate (OR 2.82, 95% CI 1.57 to 5.07, P = 0.0005; 447/478 [93.5%] versus 198/229 [86.5%]; absolute risk difference + 7.6%, 95% CI 2.9% to 12.4%) and with a small reduction in estimated intraoperative blood loss (MD -23.91 mL, 95% CI -35.79 to -12.03, P < 0.0001; three studies). No statistically significant differences were detected for operative time (MD 7.00 min, 95% CI -2.05 to 16.05, P = 0.13), length of hospital stay (MD -0.26 days, 95% CI -1.00 to 0.48, P = 0.49; I2 = 95%) or postoperative complications (OR 0.81, 95% CI 0.51 to 1.31, P = 0.40). Subgroup analyses by indication showed no significant interaction for any outcome (P for subgroup difference: surgical success 0.97, operative time 0.59, complications 0.98); the confidence interval for the ureteropelvic junction obstruction subgroup was wide because only two studies contributed data. Available retrospective comparative evidence suggests that preoperative ureteral rest is associated with higher surgical success after robot-assisted upper urinary tract reconstruction and with a small reduction in estimated blood loss. No clear association was observed with operative time, length of stay or postoperative complications. Because the available evidence is limited to a small number of retrospective studies with heterogeneous indications, definitions and reconstructive techniques, these findings should be considered hypothesis-generating. Current data are insufficient to establish whether the effect differs between acquired ureteral strictures and ureteropelvic junction obstruction.