Comparison of cecal abrasion and multiple-abrasion models in generating intra-abdominal adhesions for animal studies.

Background: The formation of postoperative adhesions is a common problem in abdominal surgery that may lead to serious complications. Appropriate animal adhesion models are essential for the investigation of adhesiogenesis and the development of new anti-adhesive products. Although animal models have been developed to study the process of adhesion formation in the abdomen, they are not effective in generating adhesions located over small bowel where adhesions are most commonly observed in clinical practice.

Methods: Twenty-nine Sprague Dawley rats were subjected to standardized cecal abrasion (group 1; n=9), or two types of multiple abrasion, in which cecal and 3 or 5 abrasions were performed on small bowel (group 2, n=10; and group 3, n=10). An observer blinded to the randomization assessed the difficulty of adhesiolysis on a 6-point scale, and the locations of the adhesions were recorded 21 days after the initial surgery.

Results: Adhesiolysis was significantly more difficult in group 3 than in group 1 (p=0.01). The number of animals that had adhesions between the small bowel segments and the total number of locations where small bowel adhered were significantly greater in group 2 and 3 than in group 1 (p<0.05 for all comparisons).

Conclusions: Abrasions to the small bowel created consistent adhesions that have clinical characteristics of intra-abdominal adhesions as compared to the standard cecal abrasion model and that can be used in future animal studies on adhesions.