The Influence of Procedural Volume on Short-Term Outcomes for Robotic Pancreaticoduodenectomy

Abstract

Introduction: An increasing number of robotic pancreaticoduodenectomies (RPD) are reported, with benefits in reduced complications and shortened postoperative stay. However, questions remain on the number of procedures needed for gaining technical proficiency in RPD and the impact of procedure volume on outcomes. Therefore, we aimed to assess the influence of procedure volume on short-term RPD morbidity and operative variables. Methods: A retrospective review of consecutive RPD cases performed by a single surgeon was undertaken. Cumulative sum (CUSUM) analysis was performed to identify the procedure volume threshold, following which before-threshold and after-threshold outcomes were compared. Results: Since May 2017, 57 patients underwent an RPD at our institution. The median operative time was 360 min (IQR 300 – 445 min). The overall morbidity (Clavien-Dindo grade ≥3) in the cohort was 27.1%. The postoperative pancreatic fistula rate was 8.3% (all grade A), while the re-operation rate was 6.3%. CUSUM analysis has identified 20 cases as proficiency threshold, indicated by curve inflexion (Figure 1). Median operative time was significantly shorter after the threshold of 20 cases (470 min vs 320 min, p<0.001). However, no significant difference between before- and after-threshold groups in median Clavien-Dindo complication grade (0.5 vs 1.5, p=0.675) was found. Conclusion: A decrease in operative time after 20 RPD cases suggests a threshold of technical proficiency potentially associated with an initial adjustment to new instrumentation, port placement and standardisation of operative step sequence. Nonetheless, no clinically meaningful decrease in short-term morbidity was found during the initial learning phase, suggesting its safety.