Altered systemic organ blood flow after combined injury with burn and smoke inhalation

Systemic organ blood flow was longitudinally determined with fluorescent microspheres after severe thermal injury in unanesthetized sheep. After chronic instrumentation, 20 sheep were subjected to combined injury with 40% body surface area third-degree burn and 48 breaths of cotton smoke insufflation. During the next 72 h of the experimental period, all animals were resuscitated with Ringer's lactate following the Parkland formula. To test the effect of systemic administration of ibuprofen, animals were assigned to the control group (n=11) or the ibuprofen group (n=9). In the ibuprofen group, animals received ibuprofen as a 12 mg/kg bolus injection 1 h after injury and 6 mg/kg/h as a continuous infusion for the next 47 h. After this combined injury, animals exhibited a biphasic hemodynamic alteration, with an initial shock period and a later hyperdynamic period, a phenomenon often seen in severely burned patients. Among multiple organs, the splanchnic organs exhibited more dominant and sustained decreases in regional blood flow, whereas heart and kidney blood flow were maintained at more than 90% of baseline level even in the initial hypovolemic phase. In the postresuscitation period, no organ except the heart showed increased regional blood flow, despite a more than 20% increase in cardiac output. Ibuprofen had effects on early recovery from the initial shock period, and it improved intestinal organ blood flow, suggesting a potential benefit of this drug for severe thermal injury.