Alcohol ingestion before burn injury decreases splanchnic blood flow and oxygen delivery

Recent studies from our laboratory have shown that alcohol and burn injury impair intestinal barrier and immune functions. Although multiple factors can contribute to impaired intestinal barrier function, such an alteration could result from a decrease in intestinal blood flow (BF) and oxygen delivery (DO2). Therefore, in this study, we tested the hypothesis that alcohol ingestion before burn injury reduces splanchnic blood flow and oxygen delivery. Rats (250 g) were gavaged with alcohol to achieve a blood ethanol level in the range of 100 mg/dl before burn or sham injury (25% total body surface area). Day 1 after injury, animals were anesthetized with methoxyflurane. Blood pressure, cardiac output (CO), +/-dP/dt, organ BF (in ml.min(-1).100 g(-1)), and DO2 (in mg.ml(-1).100 g(-1)) were determined. CO and organ BF were determined using a radioactive microsphere technique. Our results indicate that blood pressure, CO, and +dP/dt were decreased in rats receiving a combined insult of alcohol and burn injury compared with rats receiving either burn injury or alcohol alone. This is accompanied by a decrease in BF and DO2 to the liver and intestine. No significant change in BF to the coronary arteries (heart), brain, lung, skin, and muscles was observed after alcohol and burn injury. In conclusion, the results presented here suggest that alcohol ingestion before burn injury reduces splanchnic BF and DO2. Such decreases in BF and DO2 may cause hypoxic insult to the intestine and liver. Although a hypoxic insult to the liver would result in a release of proinflammatory mediators, a similar insult to the intestine will likely perturb both intestinal immune cell and barrier functions, as observed in our previous study.