Prosthetic mesh contamination during NOTES(®) transgastric hernia repair: a randomized controlled trial with swine explants.

PURPOSE: Natural Orifice Translumenal Endoscopic Surgery (NOTES(®)) is a developing field in minimally invasive surgery that has been applied across a wide range of procedures; however, infectious concerns remain. Most of the applications have been for extraction, rather than reconstructive procedures. Prosthetic hernia repair, is a constructive procedure, has the unique challenge of avoiding contamination and infection of a permanent implant. Utilizing a novel device, we hypothesize that we can significantly reduce or eliminate prosthetic contamination during a transgastric approach for delivery of a clinically relevant, permanent, synthetic prosthetic.
METHODS: 20 swine explants of stomach with attached esophagus were prepared by placing an ultraviolet (UV) light sensitive gel within the lumen of the stomach. Each stomach then underwent endoscopic gastrotomy utilizing a needle, wire guide, and 18-mm balloon dilator. A 10 × 15 cm polypropylene prosthetic was rolled and tied with a 2-0 silk suture, and delivered with one of two methods. Group A (control) utilized a snare to grasp the prosthetic adjacent to the endoscope, which was used to drag it through the gastrotomy. Group B (device) utilized a modified esophageal stent delivery system to deliver the prosthetic through the gastrotomy. Each prosthetic was then digitally photographed with UV illumination, with the contaminated areas illuminating brightly. Software analysis was performed on the photographs to quantify areas of contamination for each group. Statistical analysis was performed using a two-tailed t test with unequal variance.
RESULTS: Group A demonstrated a mean of 57 % of the surface area of the prosthetic contaminated with UV light sensitive gel. Group B (experimental group) showed a mean of 0.01 % of the surface area contaminated (p < 0.0001). 95 % confidence intervals indicated that the unprotected delivery technique exposes approximately 6,000 times more of the surface area to contamination than the delivery device.
CONCLUSION: Use of this modified stent delivery system can nearly eliminate prosthetic contamination when placed via a transgastric approach in a swine explants model. Theoretically, the reduced inoculum size would reduce or eliminate clinical infection. Since the inoculum size required for clinical prosthetic infection for intraperitoneal mesh is unknown, further study is warranted to test the ability to eliminate clinical infection related to prosthetic delivery with this technique.