Background: Significant bowel distention can result from lumenal gas insufflation during NOTES procedures. This can reduce the peritoneal cavity operative domain. Bowel distention may be more apparent with tunneling-type access techniques that require more time to cross the viscus wall. Objective: Utilizing commercially available products, we designed an intestinal occlusion catheter (IOC) that can be positioned distal to the translumenal access site. We assessed its ability to minimize bowel distention during a NOTES operation. Methods: We obtained transgastric peritoneal access in 6 swine (mean 30 kg) utilizing a submucosal tunneling technique. An IOC was placed in the duodenum. Briefly, the IOC was grasped with endoscopic forceps and advanced through an overtube parallel to the endoscope. After positioning, the IOC was inflated. Occlusion was maintained for the duration of the procedure. Degree of bowel distention was subjectively noted at the conclusion of the operation. IOC pressure was measured with inflation and reassessed prior to removal. The animals were sacrificed at two weeks and necropsy was performed to assess for duodenal injury. Results: IOCs were successfully placed in all 6 animals. Placement time was 209 ± 62 seconds. Initial balloon pressure was 39 ± 4.8 mmHg. Bowel occlusion was maintained for 148 ± 20 minutes. The IOC failed in 2 animals (33%). Failure, readily detectable as increasing small bowel distention, resulted from balloon rupture (n=1) or back migration (n=1). IOC pressure at the conclusion of the case was 34 ± 1.3 mmHg. The IOC subjectively improved the working domain and enhanced visualization of the viscera. Necropsy revealed no evidence of duodenal injuries. Conclusion: Placement of an IOC may be of benefit for NOTES procedures. Successful occlusion minimized bowel distention and improved abdominal working space. All study animals had an IOC placed with minimal time requirements, but the failure rate suggests a need for improved design. We have not determined the optimum occlusion pressure to minimize distention and to allow adequate mucosal blood flow, however no signs of ischemia were noted at necropsy. We are encouraged by our experience using the IOC and believe that it holds promise as an adjunct for NOTES procedures. We are currently evaluating a more robust design to improve the IOC failure rate.
Program Number: P196