DAILY VARIATION IN PORTAL BLOOD-FLOW AND THE EFFECT OF PROPRANOLOL ADMINISTRATION IN A RANDOMIZED STUDY OF PATIENTS WITH CIRRHOSIS

A nocturnal increase in portal pressure and blood flow was demonstrate d in patients with cirrhosis, suggesting that these hemodynamic change s may contribute to the triggering of the hemorrhagic episodes observe d during the night in these patients. It is known that propranolol red uces portal flow, thus reducing the risk of variceal bleeding. In a do uble-blind, placebo-controlled study, we evaluated the effect of long- term propranolol administration on the daily fluctuation of systemic a nd splanchnic hemodynamic parameters in 14 patients with cirrhosis. Ca rdiac output and portal blood flow were measured by the Doppler techni que. A daily fluctuation of both cardiac output and portal blood flow was observed, peaking at midnight. beta-Adrenergic blockade was manife sted by a significant reduction in heart rate (-21% +/- 4%, P < .01) a nd cardiac output (-12% +/- 2%, P < .05). A significant decrease in po rtal blood flow (-20% +/- 4%, P < .01) was also observed in these pati ents. Propranolol administration blunted the time-related changes in c ardiac output and portal blood flow. In contrast, patients receiving p lacebo had a nocturnal peak of both parameters similar to that observe d under basal conditions. Our study shows that chronic propranolol adm inistration abolishes the nocturnal peak of portal blood flow in patie nts with cirrhosis and indicates a preventive effect of propranolol in these patients.