Page 56 - Postoperative Intra-Abdominal Adhesions- New insights in prevention and consequences

Chapter 3
Materials and methods:
Study design:
A reproducible rat model was used to investigate adhesion formation. 106 WAG/Rij rats were assigned to nine different groups: 14 animals per group in experiment one and 10 animals per group in experiments two and three. In each group a standardized peritoneal trauma was created and with exception of the control group an anti-adhesive agent was applied. After two weeks the animals were humanely sacrificed and adhesions were scored on quantity and severity. In experiment three the animals were sacrificed after four and six weeks
Animals:
Female WAG/Rij rats weighing 125-175 gram with an age of 9-11 weeks were obtained from a licensed breeder and accustomed to laboratory conditions for two weeks before the start of the experiment. The animals were kept under standard laboratory conditions (temperature 20-24°C; relative humidity 50%-60%; 12 hour light and 12 hour dark cycles) and had free access to water and standard rat food during the whole experimental period. The protocol of the experiment was approved by the Animal Experiments Committee of the Erasmus University Rotterdam.
PVA/CMC hydrogel
A-Part gel consists of polyvinyl-alcohol (PVA) and carboxymethylcellulose (A-Part®; B.Braun Aesculap). PVA is the anti adhesion component while carboxymethylcellulose promotes attachment at the wound side. The gel acts like a physical barrier and is applied at the end of the operation. PVA/CMC gel is completely absorbed in three to four weeks and its main route of excretion is via the urine.
Icodextrin
Icodextrin 4% (Adept®; Baxter USA) is a high molecular weight a-1,4 glucose polymer solution. It is metabolized by a-amylase to oligosaccharides, but since amylase is absent in the peritoneal cavity icodextrin 4% has a prolonged absorption time up to 3-5 days. Finally absorption occurs via lymphatic drainage into the systemic system. The
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