Different transgastric access techniques for natural orifice transluminal endoscopic surgery (NOTES) have been described.

To evaluate different methods of transluminal access with regard to leak pressures after the procedure.

Experimental endoscopic study in an ex vivo porcine stomach model.

The following endoscopic techniques for transgastric access were evaluated in 34 stomachs: (1) 1.5-cm to 2-cm linear incision, (2) balloon dilation after needle-knife puncture, (3) via a short submucosal tunnel, and (4) via an extended submucosal tunnel. For techniques 3 and 4, a submucosal tract was endoscopically created by physically separating the mucosa from the muscularis. Mucosal incisions were closed by the standardized application of clips. Handsewn gastric closure after a linear needle-knife incision served as a positive control, whereas, open 1.5-cm to 2-cm gastrotomies were negative controls. After the procedure, pressures to liquid leakage were recorded.

The unclosed controls demonstrated leakage at mean (SD) 2 ± 2 mm Hg, which represents a baseline system resistance. The handsewn gastric closure after linear incision leaked at 50 ± 7 mm Hg. The needle-knife gastrotomy, the balloon dilation, the short submucosal tunnel, and the extended submucosal tunnel leaked at 37 ± 15 mm Hg, 41 ± 24 mm Hg, 44 ± 13 mm Hg, and 87 ± 19 mm Hg, respectively. There were significant differences in leakage pressures between the group with the extended submucosal tunnel and all other transgastric access techniques (all P ≤ .002).

The extended submucosal tunnel yielded the best leak resistance, which is superior to standard transgastric access methods and rival handsewn interrupted stitches.