SPLANCHNIC AND PERIPHERAL TISSUE PERFUSION IN EXPERIMENTAL FAT-EMBOLISM

Objective: To investigate the acute effects of experimental fat emboli sm on splanchnic and peripheral perfusion and oxygenation in pigs. Des ign: Randomized, controlled trial. Setting: Animal laboratory. Subject s: Eighteen domestic pigs, weighing 25 to 31 kg. Interventions: The 18 pigs were randomized to either the fat embolism or control groups. Ni ne anesthetized and mechanically ventilated pigs were intracavally inf used with a 10% allogeneic bone marrow suspension at a dose of 100 mg/ kg over 5 mins (the fat embolism group); nine control pigs received no rmal saline in the same volume and speed (control group). Measurements and Main Results: Mean pulmonary arterial pressure, pulmonary vascula r resistance, and pulmonary shunt increased, and Pao(2) decreased imme diately after the bane marrow suspension infusion, In the fat embolism animals, oxygen delivery decreased, oxygen content difference widened , and total oxygen consumption remained high, indicating enhanced oxyg en extraction, Further, superior mesenteric artery blood flow and mese nteric oxygen delivery decreased, while intramucosal pH in the small b owel was stable. Subcutaneous Po-2 decreased in both groups, whereas t ranscutaneous Po-2 decreased only in the animals receiving bone marrow suspension, Skin red cell flux showed no significant changes. Conclus ions: The present model of fat embolism results in significant impairm ent in systemic oxygenation, Despite this fact, the intestinal oxygena tion remains unaffected probably due to sufficient compensatory mechan isms, Transcutaneous Po-2 measurements may provide a useful index for early detection of fat embolism.