Assessing transgastric Natural Orifice Transluminal Endoscopic Surgery prior to clinical implementation.

The objective was to investigate whether transgastric Natural Orifice Transluminal Endoscopic Surgery (NOTES) could be implemented safely in clinical practice. The experimental studies proved ultrasonography guided access through the stomach to be feasible and safe without iatrogenic complications. Although the technique was safe, further development is needed to increase reproducibility and reduce the procedural time used for gaining access. Closing the gastrotomy after the procedure can be performed easily by application of an endoscopic clip (Over-The-Scope-Clip). Microscopic evaluation of excised gastrorrhaphies revealed that sufficient healing had been achieved after long-term follow-up. A fundamental problem with TG peritoneoscopy is the lack of NOTES specific endoscopes. With the combination of intraluminal EUS and peritoneoscopy with extraluminal EUS, it was possible to achieve sufficient visualisation of anatomical structures of interest in the diagnostics and staging of upper gastrointestinal cancers. Another problem with TG NOTES is the risk of intra-abdominal infections. Using a multimodal decontamination regimen reduced the rate of intra-abdominal pathology, but the risk of intra-abdominal abscess formation as a result of contamination from the access route was still present. To reduce this contamination, mouthwash with chlorhexidine was effective in a human randomised study. The same study also found significant higher bacterial load in the stomach of patients using proton pump inhibitor, emphasising the need to pause PPI prior to future TG interventions. Whether the risk of infectious complications after TG NOTES is comparable between animals and humans is debatable. Despite this, the subject of infectious complications and the safety profile of the TG technique require further research. Based on the evidence available in the literature and current experience, clinical implementation to the benefit of patients does not seem justifiable at present time.