Prospective Randomized Comparison Of Gastrotomy Closure Associating Tunnel Access And Over-The-Scope Clip (Otsc) With Two Other Methods In An Experimental Ex Vivo Setting

Background: Safe transgastric natural orifice transluminal endoscopic surgery (NOTES) procedures require a reliable closure of the gastrotomy. Recently a novel peritoneal access method via a submucosal tunnel has been described with encouraging preliminary results.Aim: The aim is to compare a submucosal tunnel access plus over-the-scope clip (OTSC) system for closure with two other closure modalities.Patients and methods: This is a prospective ex vivo study conducted on 42 porcine stomach models equally randomized into three groups in an academic medical center. The procedures performed in each group included: (1) Tunnel (6cm) +endoclips; (2) Knife+balloon dilation access+ OTSC; and (3) Tunnel+OTSC. A pressurized air-leak test was performed to evaluate the strength of the closure. Stomach volumes, procedure times, number of clips, and incision sizes were also registered.Results: The mean air-leak pressure was statistically higher in Group 3 than in Groups 1 and 2-95.2 +/- 19.3 mmHg versus 72.5 +/- 35.2 and 79.0 +/- 24.5 mmHg (P<0.05). The gastrotomy creation times for Groups 1, 2, and 3 were 28.0 +/- 10.1, 4.3 +/- 1.4, and 20.1 +/- 10.6 minutes, respectively, with significantly lower time in Group 2 (P<0.001). The closure times were 16.1 +/- 6.1, 6.5 +/- 1.2, and 5.3 +/- 3.0 minutes, respectively, and significantly longer in the endoclip group (P<0.001). There were no differences in the volumes and the incision sizes among the three groups.Conclusion: The combination of a submucosal tunnel access and OTSC offers a stronger closure than the other methods studied.