Assessment of the learning curve for the novel transanal minimally invasive surgery simulator model

Transanal minimally invasive surgery (TAMIS) is technically demanding and requires extensive training. We developed the TAMIS simulator model by remodeling an existing laparoscopic training system to educate trainees and analyzed their learning curves.

Between March 2020 and June 2020, 12 trainees performed TAMIS simulator training sessions. The total operative time, including specimen removal and wound closure, was recorded. The wound closure and specimen quality, trainee self-confidence, and supervisor evaluation of technical performance were documented. A moving average was used to analyze the number of training sessions required to stabilize the procedure time, while a cumulative sum analysis was performed to identify that required to reach proficiency with each item.

Each trainee completed 20 TAMIS simulator training sessions. The median total procedure time was 13 min (range, 4-60 min), which stabilized after 15 training sessions. The median times for specimen removal and wound closure were 3 min (range, 1-18 min) and 10 min (range, 2-50 min), respectively, which stabilized after 7 and 15 training sessions, respectively. The mean specimen and wound closure quality scores were 2.9 ± 0.9 (on a scale from 1 to 4) and 2.3 ± 1.1 (on a scale from 1 to 4), respectively, competencies in which were achieved after 16 and 20 training sessions, respectively. The mean trainee self-confidence and supervisor evaluation of technical performance scores were 2.4 ± 1.2 (on a scale from 1 to 5) and 2.7 ± 1.2 (on a scale from 1 to 5), respectively, competencies in which were achieved after 20 and 17 training sessions, respectively.

Trainees required 15 training sessions to stabilize the procedure time and 16-20 training sessions to demonstrate competencies with the TAMIS simulator model. We expect this simulator model may help surgeons more rapidly acquire the skills required for TAMIS.