Learning curve for uniportal video-assisted thoracoscopic anatomical segmentectomy

Background: Anatomical segmentectomy by uniportal video-assisted thoracoscopic surgery ( U-VATS) is a delicate surgical procedure. Hitherto, only few studies have assessed the learning curves of anatomical segmentectomy by U-VATS, with varying data available. The present study aimed to investigate the learning curve and clinical advantages for U-VATS segmentectomy. Methods: The medical records of patients who underwent U-VATS or non-U-VATS segmentectomy between August 2017 and May 2020 were retrospectively reviewed. Cumulative sum (CUSUM) analysis was employed to illustrate the learning curve of U-VATS segmentectomy. Perioperative parameters were used to determine the structural intervals of the learning curve, and to compare U-VATS and non-U-VATS segmentectomy. Results: In total, 122 patients receiving U-VATS segmentectomy and 98 patients receiving non-VATS segmentectomy were included. Of these, 116 patients underwent successful U-VATS segmentectomy, while the other six patients underwent conversions. The structural intervals of 20-29 cases and 58-63 cases were determined as the threshold according to the CUSUM analyses. The learning process of U-VATS segmentectomy was therefore divided into three phases. Interestingly, the perioperative parameters differed significantly between Phases 1 and 3, including operative time (Op-T), postoperative hospital stays (Po-Hst), postoperative thoracic drainage (Po-D), and operative failure (Po-F) rates (P<0.05). Moreover, U-VATS segmentectomy in Phase 3 was associated with significantly shorter Po-Hst and Op-T, less Po-D, and reduced postoperative pain compared with non-U-VATS (P<0.05). Conclusions: U-VATS segmentectomy is an ideal alternative to non-U-VATS segmentectomy. Surgeons can preliminarily complete U-VATS anatomical segmentectomy after performing 20-29 cases, and can master the surgical techniques after completing 58-63 cases.