Modulation of splanchnic circulation: Role in perioperative management of liver transplant patients

Figure 1 Fluid loading in a healthy subject. Low vascular compliance combined with decreased pooling of blood in splanchnic circulation is associated with increased central venous pressure.

Figure 2 Fluid loading in a cirrhotic patient. High vascular compliance combined with increased pooling of blood in splanchnic circulation is associated with a minimal increase in central venous pressure.

Figure 3 Anatomy of splanchnic blood flow. The liver receives 25% of its arterial blood supply via the hepatic artery and the remaining 75% via the portal vein.

Figure 4 Distribution of catecholamine receptors in the splanchnic area. The hepatic artery contains α1-, α2-, and β2-adrenergic receptors; the preportal (intestinal capacitance) and portal veins contain α-adrenergic, but not β2-adrenergic receptors. Capacitance vessels located inside the liver contain only α-adrenergic receptors, while the hepatic veins contain both α- and β2-adrenergic receptors.

Figure 5 Effect of stimulation of catecholamine receptors within the splanchnic area on blood flow. Stimulation of α receptors in the pre- and post-portal capacitance vessels failed to create a gradient sufficient to shift blood from splanchnic to systemic circulation.

Figure 6 Distribution of vasopressin receptors in the splanchnic area. V1a receptors are more prevalent on the portal venous side than the arterial side.