Air and fluid leak tests after NOTES procedures: a pilot study in a live porcine model (with videos)

Abstract

Background: Transluminal access site closure remains a major challenge in natural orifice transluminal endoscopic surgery (NOTES).

Objective: Our purpose was to develop in vivo leak tests for evaluation of the integrity of transgastric access closure.

Settings: Survival experiments on 12 50-kg pigs.

Design and interventions: After a standardized transgastric approach to the peritoneal cavity and peritoneoscopy, the gastric wall incision was closed with T-bars (Wilson-Cook Medical, Winston-Salem, NC) deployed on both sides of the incision and then cinched together. Gastrotomy closure was assessed with air and fluid leak tests. The animals were observed for 1 week and then underwent endoscopic evaluation and necropsy.

Main outcome measurements: (1) Leak-proof closure of the gastric wall incision. (2) Gastric incision healing 1 week after the procedure.

Results: The mean intraperitoneal pressure increased 10.7 +/- 3.7 mm Hg during gastric insufflation when the air leak test was performed before closure compared with 0.9 +/- 0.8 mm Hg after transmural closure of the transgastric access site with T-bars (P < .001). Fluid leak tests demonstrated no leakage of liquid contrast from the stomach into the peritoneal cavity after closure. Necropsy in 1 week confirmed completeness of the gastric closure in all animals with full-thickness healing and no spillage of the gastric contents into the peritoneal cavity.

Limitations: Leak tests were only evaluated on an animal model.

Conclusions: Fluid and air leak tests are simple techniques to evaluate in vivo the adequacy of the transluminal access site closure after NOTES procedures. Leak-proof gastric closure resulted in adequate tissue approximation and full-thickness healing of the gastric wall incision.