Tract formation following percutaneous endoscopic gastrostomy in an animal model

Complications of percutaneous endoscopic gastrostomy (PEG) have often been related to the application of excessive traction to the gastrostomy tube in an attempt to achieve immediate juxtaposition of the gastric and abdominal walls. Recent clinical reviews have suggested that complication rates can be reduced by avoiding such traction and leaving a longer tract between these structures. Laboratory evaluation of tract development has been lacking. The present study was designed to evaluate tract formation in an animal model. Eight mongrel dogs underwent PEG placement using silastic (n = 4) or latex (n = 4) catheters. Two animals from each group were subsequently sacrificed at 1 week and the remaining animals, at 2 weeks. In each animal, 6 cm catheter length was left between the gastric and the abdominal walls. This distance was assured by crossbar and suture fixation of the catheter at the skin entry site. Complete tract formation was evident in all animals at the time they were sacrificed, with no significant gross or histologic differences being noted between the silastic and the latex groups. Increased collagen deposition was noted at 2 weeks in comparison with that observed at 1 week. In an additional three animals, the same procedure was performed, but the catheter was not secured to the abdominal wall at the site of skin penetration. In these animals, tract formation was incomplete as late as at 2 weeks, but there were no associated complications. We conclude that early PEG tract formation is not dependent on the immediate proximity of the gastric and abdominal walls. The type of catheter used does not dictate the time course of early tract development.(ABSTRACT TRUNCATED AT 250 WORDS)