Vasoactive Drugs and Splanchnic Perfusion

Abstract

Vasoactive drugs, especially sympathomimetic amines, are often needed to support tissue perfusion in circulatory failure. The effects of sympathomimetic drugs on splanchnic circulation and metabohsm have not been well documented in humans. Based on the available data, it seems evident that the regional hemodynamic effects of various vasoactive drugs in intensive care patients can neither be predicted from their pharmacological characteristics alone nor extrapolated from experimental models. Inadequate splanchnic tissue perfusion may contribute to the development of multiple organ failure and ultimately death in critically ill patients. The catecholamines used to support the circulatory functions may markedly modify the activity of various metabolic pathways in the liver and simultaneously alter the splanchnic blood flow and its distribution. Accordingly, catecholamines may induce regional perfusion abnormalities and alter the balance between regional oxygen delivery and tissue metabolic demands. Due to these interactions, the effects of vasoactive drugs on splanchnic oxygen transport and substrate metabohsm should be evaluated in intensive care patients.