DOES THE ROUTE OF FEEDING MODIFY THE INFLAMMATORY RESPONSE

Objective The authors compared the responses to endotoxin in enterally and parenterally fed human volunteers. Background Recent investigatio ns have reported that the response to endotoxin in humans is greater i n individuals who receive parenteral nutrition rather than enteral fee ding. It was proposed that this difference was related to gut barrier dysfunction during intravenous nutrition. To evaluate this hypothesis, the authors analyzed the responses of human subjects to an intravenou sly administered bolus of endotoxin after enteral or parenteral nutrit ion. Methods Fifteen randomly selected healthy volunteers were studied during two separate investigations; ten studies were performed in ten subjects who received enteral nutrition, and nine studies were carrie d out in five additional subjects who received parenteral nutrition. A fter 2 days of enteral feedings or 7 days of parenteral feedings, endo toxin was administered by intravenous injection; temperature, symptom score, and duration then were measured serially. Blood samples were ob tained for leukocyte and platelet count, and plasma concentrations of corticotrophin, cortisol, epinephrine, norepinephrine, tumor necrosis factor, and interleukin-6. Mononuclear cell response to phytohemagglut inin was determined at 0, 4, and 24 hours. Results In the parenteral g roup, a diminished response was observed in platelet count and plasma interleukin-6 levels compared with volunteers who received enteral nut rition. The duration of symptoms tended to be reduced in the parentera lly fed group, although this did not achieve significance. Other respo nses were not significantly different between the two groups. Conclusi on The responses to endotoxin in human subjects who received parentera l nutrition were similar compared with subjects who received enteral n utrition, although platelet count and plasma interleukin-6 concentrati on were diminished.