Learning curve of single-incision thoracoscopic surgery for primary spontaneous pneumothorax

Background Single-incision thoracoscopic surgery (SITS) requires extensive time and practice to achieve satisfactory technical skills. The aim of this study was to evaluate the learning curves of SITS for primary spontaneous pneumothorax (PSP). Methods This study included a total of 274 consecutive patients who underwent PSP surgery by a single operator between May 2011 and February 2014. During this period, SITS was applied as a routine approach. Learning curves were made by the cumulative sum (CUSUM) method using the number of cases and four surgical technique-related factors, including operation time, postoperative complication, non-SITS rate, and ipsilateral PSP recurrence. Results Among the 274 patients, 16 patients who were presented with a previous 3-port wound scar or inadequate chest tube site before surgery were not eligible for SITS. Hence, SITS was attempted on 258 patients and performed successfully in 251 patients. For these successful SITS patients, the mean age was 22.9 +/- 8.1 years, the mean operation time was 65.6 +/- 22.2 min, the mean chest tube indwelling time was 1.5 +/- 1.1 days, and the mean postoperative hospital stay was 1.7 +/- 1.1 days. The mean operation time decreased from 84.0 to 47.6 min when a comparison was made between patients operated in the initial 6 months and the last 6 months of the study period. As revealed by the CUSUM technique, more than 50 % of the cases experienced an operation time of < 70 min after the first 92 cases. After 57 cases, the postoperative complication rate was maintained at < 5 %. The non-SITS rate was achieved to be lower than 5 % after 112 cases. The ipsilateral PSP recurrence rate was maintained at below 8 % after 102 cases. Conclusions Although PSP is the most applicable scenario for the beginner of SITS, at least 100 cases of experience are needed to achieve optimal technical level.