Oxygen Transport and Consumption in Cirrhosis

A hyperdynamic systemic circulation is often observed in cirrhosis, especially in patients with impaired liver function. Features compatible with tissue hypoxia have recently been observed in patients with cirrhosis and hepatic insufficiency. Nitroglycerin is a venodilator which has been proposed for treatment of portal hypertension in patients with cirrhosis and to counteract the adverse effects of vasopressin on systemic hemodynamics. Oxygen deprivation appears to be due to arteriovenous shunting-induced limitation of tissue O2 extraction. Additionally, insufficient increase in O2 transport may contribute to impaired O2 supply to tissues. Limitation of tissue O2 extraction is responsible for an abnormal O2-supply dependency which may be unmasked by using drugs such as nitroglycerin and vasopressin.