Special Feature: Oral Presentations
BRIDGING MESENTERIC ISCHEMIA USING PERITONEAL PERFUSION WITH OXYGENATED PERFLUOROCARBONS – LOCAL AND SYSTEMIC RESULTS
For treatment for mesenteric ischemia, abdominal dialysis with oxygenated perfluorocarbons (PFCs) has been proposed. In small animal settings, this therapy has been shown to reduce effects of intestinal ischemia such as serum lactate, bowel mucosa status and translocation. We developed a PFC-application system for use in man and studied the local and systemic effects of this therapeutic concept in a near-human animal model. A system capable of cleaning, oxygenating, heating and circulating 800 ml/min PFC through the abdominal cavity was developed. Following approval of the local ethical committee, 18 pigs of 75 kg were starved for 24 hours with water ad libitum. They were anesthetized and their hemodynamics and regional perfusion monitored. Blood flow in the superior mesenteric artery was reduced to 20% (ISCH, n=6) for 4 hrs, followed by 1 hr of reperfusion. In the therapy group (n=6, THER), oxygenated PFC (Fluorinert FC-77, 3M Deutschland), was simultaneously circulated through the abdomen. Six animals received only SHAM surgery. After sacrificing, bowel tissue was examined for mucosal damage. Perfusing the abdomen with sufficient flow and reaching all parts of the bowel proved challenging due to anatomical reasons and required several technological solutions. Cardiac, circulation, and oxygenation parameters did not differ significantly between groups. Histological examination and scoring of bowel tissue samples showed no damage in SHAM, and equally extensive damage in ISCH and THER. Although partially effective in small animal experimental settings, intraabdominal application of oxygenated PFC presents no viable therapeutic concept for bridging intestinal ischemia in a porcine model of human dimensions. Limited O2-diffusion capacity through the bowel wall, O2-mismatch, and the abdominal cavity's anatomical resistance to PFC flow contributed to the therapy's failing.
Note. This study was supported by the European Union's Interreg IIIA-initiative.Copyright © 2006 by the American Society for Artificial Internal Organs