Mastering the robot-assisted pyeloplasty learning curve: analysis of operative efficiency, safety, and functional outcomes

Abstract

Robot-assisted pyeloplasty (RAPY) for ureteropelvic junction obstruction (UPJO) is a technically challenging procedure. This study evaluates the learning curve by analyzing operative time, complications, and renal function recovery across sequential cases. A retrospective study of sixty consecutive patients who underwent RAPY between 2019 and 2024, performed by a single surgeon in a specialized robotic department, was performed. Cases were divided into three phases: early (first 20), middle (21-40), and late (41-60). Outcomes included operative time, complications (as classified by the Clavien-Dindo system), length of hospital stay, and improvement in glomerular filtration rate GFR. Mean age was 56 years, 57% of UPJO was on the left side. 55% of patients were males, 90% presented with symptoms, and the mean lateral distribution of the affected kidneys in renal scintigraphy statistical analysis was 32%. All preoperative parameters showed no significant differences among the study groups. The mean console time was 91 min. The mean hospital stay was 4.8 days, and the mean bladder catheter days were 4.2 days. Operative time decreased significantly from the early to the late phases (118 ± 28 vs. 65 ± 18 min, p < 0.001). The overall complication rate was 16%, minor complications 11%, and major complications 5%. Major complications (Clavien ≥ III) decreased from 25 to 5% (p =0.02) from the early to the late phase. Five patients were readmitted within 90 days after surgery. GFR improvement was consistent across all phases (+ 14.2 mL/min, p =0.25). The RAPY learning curve plateaus at 40 cases, with optimized efficiency and safety and significant improvements in both efficiency and safety until then.