Experimental trial of transvaginal cholecystectomy: an ex vivo analysis of the learning process for a novel single-port technique

Background Interest in natural orifice transluminal endoscopic surgery (NOTES) has expanded, and the first experiences with patients using different techniques have been reported. However, no work has addressed the learning process or the limitations of the procedures. The relation between inexperience and complications became a major concern after the introduction of laparoscopic surgery. This study investigates the learning process for a new technique using specially designed instruments in an ex vivo model before clinical application. Methods Specially designed instruments and a single-port technique using the Tuebingen Trainer were used to evaluate instrument and surgeon performance (learning curve) in terms of time and errors. A total of 90 procedures performed by three surgeons were evaluated. Group and individual learning curves were plotted. Results All the surgeons showed a reduction in both mean cholecystectomy time (subject A: 27.2 vs 16.6 min; subject B: 21.4 vs 19.22 min; subject C: 21 vs 19.7 min) and mean errors (subject A: 2.8 vs 1.6; subject B: 3.5 vs 2.6; subject C: 3.5 vs 2). A plateau was reached after approximately 15 procedures. Group learning curve analysis showed a significant reduction in time between the first group (mean, 24.97 ± 5.8 min) and last group (mean, 19.30 ± 3.09 min; F [1,28] = 11.83; p = 0.001) for 15 procedures, as well as reduced technical errors in the fifth group, from 3.7 ± 1.65 to 1.6 ± 1.04 ( F [1,28] = 8.90; p