Evaluation of a sprayable polyethylene glycol adhesion barrier in a porcine efficacy model

Abstract

Background: The formation of adhesions following pelvic surgery remains one of the leading causes of infertility, small bowel obstruction and re-operation for pelvic pain. A novel hydrophilic polyethylene glycol based adhesion barrier (SprayGel) is formed by simultaneously spraying two liquid precursors onto surgical sites. The liquids polymerize to form a gel that effectively coats and adheres to tissue. After about 5 days, the hydrogel layer is absorbed and subsequently undergoes renal clearance. It is believed that the presence of such a barrier would inhibit the formation of adhesions following surgical insult. Methods: A porcine adhesion model was developed wherein bilateral uterine horn transection and re-anastomosis, along with peritoneal side wall excision was performed via laparotomy. In each animal (n = 10, including the pilot study) one pelvic side wall was treated with adhesion barrier, while the contralateral side remained untreated. Results: At second look laparoscopy, 90% of the untreated sites had adhesions, compared with 30% of the treated sites (P = 0.006). Also observed were statistically significant reductions in the adhesion extent (P = 0.029) and adhesion severity scores (P = 0.023) at the treated sites. However, if the pilot study was excluded (n = 8) the differences obtained were no longer significant. Conclusions: Polyethylene glycol (SprayGel) merits further investigation as an effective barrier to the formation of post-operative adhesions in this porcine model.