Page 72 - Postoperative Intra-Abdominal Adhesions- New insights in prevention and consequences
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Chapter 4
PVA gel
Polyvinyl alcohol gel (A-Part Gel®) consists of PVA and CMC. The PVA is the anti-adhesion component, whereas the CMC prevents the gel from slipping away from the operative site. The gel acts as a barrier and is applied at the end of the operation. Polyvinyl alcohol gel is absorbed completely in three to four weeks, and its main route of excretion is via the urine19.
Study Design
Animals were anaesthetized by inhalation of an isoflurane-oxygen mixture. The abdomen was shaved and cleaned with alcohol 70%. The abdominal cavity was opened through a midline incision of 4 cm. The mesentery was cleaved one centimetre aborally to the cecum, without damaging the vessels, after which the colon was transected. An end-to- end anastomosis was formed with 12 interrupted sutures (Dafilon 8-0, B. Braun). In the study group 2.0 ml of PVA gel was applied around the anastomosis; the control group did not receive any treatment. The colon was repositioned and the abdominal wall was closed in two layers with Safil 5-0 (B. Braun). Postoperatively rats were observed and weighed daily during one week.
Outcome measurements after 7 days
On the seventh post-operative day rats were re-operated on through laparotomy. The abdomen was inspected for signs of anastomotic leakage (peritonitis with visible anastomotic dehiscence, or peri- anastomotic abscesses).
Anastomotic bursting pressure (ABP) was measured in vivo with intact adhesions. A catheter was introduced into the colon 2 cm proximally to the anastomosis, with the tip lying intraluminally at the site of the anastomosis. Subsequently, the colon was ligated proximal of the probe and distal of the anastomosis in order to create a closed cavity. The pressure in the cavity was increased by pumping air through the probe at a constant rate of 100ml/hr. One limb of the probe was connected to a pressure transducer, continuously measuring pressure during infusion. Bursting of the colon followed by a sudden drop in pressure
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