Learning Curve for Uniportal VATS Anatomical Pulmonary Resections: The Activity Monitor Operating Characteristic Method

Abstract

We aimed to analyze the learning process of the uniportal video-assisted thoracoscopic surgery (uVATS), the most up-to-date approach in VATS, to determine the learning curve cut-off value and to share the technical details in our application. Fifty patients who underwent anatomical pulmonary resection with the uVATS technique in our institute between May 2020 and June 2021 were retrospectively analyzed. The cut-off point in the learning curve (patient 26) was determined with the activity monitor operating characteristic (AMOC) method, which was developed for monitoring the most sensitive changes in the timeline. Patients were divided into two groups based on this cut-off value (group 1: first 25 patients vs. group 2: established phase, 25 patients) and compared. Comparison of groups (group 1 vs. 2) revealed a median resection time of 200 vs. 110 min (p < 0.001) and median bleeding amount of 50 vs. 30 cc (p = 0.033). Duration of pulmonary resection was statistically significantly correlated with lymph node dissection time (r = 0.698; p < 0.001) and hospital stay (r = 0.437; p = 0.029) in group 1. The most common complication was prolonged air leak (16%). The uVATS technique has video features very different from the tri-port and bi-port VATS methods. Our study using the AMOC method to compare two groups of uVATS in a continuous timeline over approximately 1 year (May 2020-June 2021) showed that, with increasing experience, resection times and bleeding amounts decreased significantly between the groups. Thus emphasizing the learning curve required for uVATS, anatomical pulmonary resection could be adequately and safely performed in all patients in this study.