Enteral nutrition ameliorates hepatic oxygenation and bioenergy status in endotoxic dogs

Since enteral nutrients vasodilate gut blood vessels, thus producing postpradial intestinal hyperemia, the purpose of this experimental study is to investigate whether this hyperemia has any beneficial effect on the disturbed hepatic oxygenation and energy charge during early endotoxemia. Fourteen dogs - after E. coli endotoxin administration through portal vein - were divided into enteral feeding groups via a jejunostomy, or placebo feeding groups. Hepatic artery and portal vein blood flow was measured through transit-time flow probes, while liver microcirculation was assessed using the laser-Doppler technique. A Clark-type electrode allowed hepatic tissue pO2 monitoring, and liver tissue samples were obtained at different periods of the study for determination of ATP, ADP and AMP by reversed phase high-performance liquid chromatography, in order to calculate energy charge. All parameters were registered before, during and after endotoxin infusion, as well as during and after enteral or placebo feeding. All the previously described parameters revealed a statistically significant decline [p<0.001] during the endotoxin infusion period in relation to baseline. After enteral feeding, all parameters exhibited a statistically significant increase in relation to controls [p<0.001]. It is concluded that enteral nutrition has a beneficial influence on the affected hepatic oxygenation and energy charge caused by early phase endotoxic shock.