Evaluation of amniotic membrane as adhesion prophylaxis in a novel surgical gastroschisis model.

Adhesions are a leading cause of bowel obstruction and infertility. The coverage of peritoneal defects, as in gastroschisis, is still a crucial problem. Despite biodegradable substitutes and synthetic implants such as PTFE membrane, a satisfactory replacement for gastroschisis has not been identified. The amniotic membrane, which is available at birth with a low antigenicity, was evaluated as a peritoneal substitute. Viable, partially viable, and inversed-used amniotic membranes were compared in a rat model. A full-thickness abdominal wall defect was made and the amniotic membrane sutured into this defect. The skin was closed over the amniotic membrane. Reoperation was performed 3 weeks after initial surgery, and the adhesion formation was measured by computerized area calculation. Viable amniotic membrane showed 0 to 3% area adhesion formation, while partially viable (50%) amniotic membrane demonstrated 33% area adhesion formation. Inversed-used amniotic membrane, with the stromal side directed toward the abdominal cavity, showed 70% of the amniotic membrane area to be covered with adhesions. The same amount was found in the control group, in which no substitute was sutured into the defect. This animal model is suitable for the straightforward evaluation of peritoneal substitutes with regard to adhesion formation. It is easy to perform and mimics surgical needs. Viable amniotic membrane proved to be an excellent antiadhesive tissue.