Page 86 - Postoperative Intra-Abdominal Adhesions- New insights in prevention and consequences

Chapter 5
that the barrier does not promote infection or abscess formation [17,18]. Cross-linked biocompatible polyvinyl alcohol (PVA) hydrogels reduce adhesion formation after non-infectious abdominal surgery [16,19,20,21]. The aim of our experiment was to investigate the effects of PVA hydrogel on adhesion and abscess formation in an experimental bacterial peritonitis and adhesion model in rodents.
Methods and Materials
To study the effects of PVA hydrogel on adhesion and abscess formation, a combination of the cecal ligation and puncture (CLP) peritonitis model and the cecal abrasion side- wall defect (SWD) adhesion model was used. We believe that our combination model resembles adhesion formation in a clinical situation after abdominal surgery in the presence of peritonitis. The protocol of the experiment was approved by the Animal Experiments Committee of the Erasmus University, Rotterdam.
Study design
In 40 male Wistar rats, the CLP model was created by ligation and puncture of the cecum. The following day, the necrotic cecum was resected and the SWD model created. The hydrogel studied in this experiment was A-Part® Gel (B. Braun Aesculap AG, Tuttlingen, Germany), which is a cross-linked PVA and carboxymethylcellulose (CMC) formulation. After completion of the SWD model, the rats were assigned randomly to one of three experimental groups: A (control), B (1 mL of A-Part® Gel), or C (2 mL of A-Part® Gel). The viscous PVA/CMC gel was administered with a special nozzle to the sites of peritoneal damage; that is, the SWD and around the cecal stump. The abdominal wall and skin were closed separately with continuous, absorbable suture. After 14 days, the animals were sacrificed humanely and scored on adhesion and abscess formation.
Procedure
Day 0: CLP model. The surgery was performed under aseptic conditions. At the start of the experiment, the animals were anesthetized using isoflurane/O2 by inhalation, and buprenorphine analgesia (0.05 mg/
84