| Abstract: | In patients with cirrhosis, endogenous catecholamines may influence the circulatory effects of propranolol. We intended to evaluate the interaction of adrenaline and propranolol on azygos blood flow, an estimate of blood flow in the superior portosystemic collateral circulation. We investigated 6 patients with cirrhosis, 5 with good liver function, receiving an intravenous infusion of adrenaline (50 ng/kg/min) before and after administration of propranolol. The median value for baseline azygos blood flow was increased from 700 ml/min (range 340-1 470 ml/min) to 1 050 (range 570-1 840 ml/min) with adrenaline alone (P less than 0.05), and decreased to 610 ml/min (range 260-1 190 ml/min) with propranolol alone (P less than 0.05). The infusion of adrenaline given after propranolol further reduced azygos blood flow to a median value of 530 ml/min (range 200-730 ml/min) (P less than 0.05). Thus, following beta-adrenergic blockade, there is a reversal of the effects of adrenaline on azygos blood flow, which corresponds to a potentiation of the effects of propranolol. Similar endogenous adrenaline-propranolol interactions may play a role in preventing recurrent variceal bleeding in cirrhotic patients. |
