Comparison of open and robot-assisted repair for ureteropelvic junction obstruction: Outcomes and direct costs from a single-institution.

Introduction: Robot-assisted laparoscopic pyeloplasty (RALP) is commonly performed to repair ureteropelvic junction obstruction (UPJO), but concerns remain regarding its efficacy and safety, as well as its cost compared to open pyeloplasty (OP). We hypothesized that primary RALP is equally efficacious to OP, with comparable direct costs.

Methods: An IRB-approved single institutional registry was retrospectively reviewed to identify all patients undergoing primary OP and RALP between July 2012 and March 2020. Intra- and postoperative surgical details were aggregated and compared. Successful reconstruction was defined as no need for additional interventions besides stent removal. Direct cost from day 0-60 from surgery was assessed for consecutive patients operated in FY2018 - 2019.

Results: Of 424 patients undergoing pyeloplasty, 346 patients were included in our analysis: 75 OP and 271 RALP. Patients underwent surgery at a median age of 39.8 months with younger patients in the OP group (p < 0.001). The 30-day complication rate was not different between groups, while higher-grade complications (Clavien G3 and 4) were significantly more prevalent in OP group (8.0 % vs 1.8 %, p < 0.01). With median follow-up of 17.5 months (IQR 8.8-34.1), no difference in overall long-term success was observed between the groups (96.0 vs 96.7, p = 0.73). The subset analysis performed for patients who had pyeloplasty at an age younger than 12 months showed similar results. 0-to-30 day direct costs were not significantly different between the two groups, but higher in the RALP group in the 30-60 day period secondary to additional procedures for stent removal. However, the total 0-60 day costs were not significantly different between RALP and OP (p = 0.47). Multivariate analyses identified 30-day post-operative complications as the only predictor for both success and direct cost.

Conclusions: In this contemporary cohort, RALP had similar success rate and was associated with fewer high grade post-operative complications compared to OP. While 30-60 day costs were higher in RALP due to post-operative stent removal, the overall 0-60 day costs were not statistically different between the two cohorts.