Robotic Proctectomy: Beyond the Initial Learning Curve.

Background: Multiple authors have described an initial learning curve (LC) for robotic proctectomy (RP), but there is scant literature regarding continued technical progression beyond this stage. Total operating time is the most commonly used metric to measure proficiency. Our goal was to examine RP experience after the initial LC looking for evidence of further technical progression.

Methods: We reviewed our robotic surgery database for a single surgeon during operations 100 through 550 to identify 83 RPs for tumor. These were divided into quartiles by series order, indicating surgeon experience level over time. Demographics and outcomes were compared among the groups. We defined (PCT) as a new metric. PCT was defined as console time divided by total operative time (TOT).

Results: From March 2014 through March 2019, 450 robotic colorectal operations were performed, including 83 RPs for polyp or cancer. No significant differences were found among the quartiles in regard to demographics, tumor features, hospital stay, conversions, or readmissions. As experience was gained, there were significant increases in intracorporeal anastomosis (ICA), TOT, and PCT. Complications decreased with experience. Number of lymph nodes in the specimen increased. On multivariate analysis, later experience group, body mass index ≥30, and ICA were associated with increased PCT.

Discussion: ICA became a routine part of RP after the initial LC, with increases in TOT and PCT. Number of lymph nodes increased and number and severity of complications decreased with experience. Increased PCT may indicate increased expertise during RP.