Hemodynamic effects of alpha-adrenergic blockade with prazosin in cirrhotic patients with portal hypertension.
This study was aimed at investigating whether the blockade of alpha 1-adrenergic receptors could reduce portal pressure in cirrhosis. Splanchnic and systemic hemodynamics were measured in 12 cirrhotic patients with esophageal varices at baseline and 1 hr after oral administration of 2 mg of prazosin (acute study). Measurements were repeated in 10 of these 12 patients after a 3-mo course of 5 mg/12 hr of prazosin (long-term study). Short-term prazosin significantly lowered the hepatic venous pressure gradient from 20.1 +/- 1.3 to 14.4 +/- 0.9 mm Hg (-25.7%) (p < 0.01), and chronic prazosin reduced it to 16.5 +/- 1.3 mm Hg (-19.1%) (p < 0.01). Hepatic blood flow was increased, thus changes in the hepatic venous pressure gradient resulted from a reduction in the estimated hepatic vascular resistance. Reductions in hepatic venous pressure gradient achieved after short-term and long-term prazosin were not significantly different. Reductions in mean arterial pressure and systemic vascular resistance were significantly greater after short-term than after long-term prazosin. Long-term prazosin was associated with significant increases in hepatic and intrinsic hepatic clearances of indocyanine green. This therapy also led to an increase in pulmonary capillary pressure (+ 28.6%, p < 0.05) and body weight (+ 3.06%, p < 0.01) and a decrease in hematocrit (-6.1%, p < 0.05) and urinary sodium excretion (-22.6%, p < 0.05). In contrast, there were no hemodynamic changes in a group of six cirrhotic patients receiving placebo. In cirrhotic patients, short-term prazosin lowers portal pressure by decreasing hepatic vascular resistance.(ABSTRACT TRUNCATED AT 250 WORDS)
Albillos
A
A
Department of Gastroenterology, Clinica Puerta de Hierro, Madrid, Spain.
Lledó
J L
JL
Bañares
R
R
Rossi
I
I
Iborra
J
J
Calleja
J L
JL
Garrido
A
A
Escartin
P
P
Bosch
J
J
D000317:Adrenergic alpha-Antagonists / Q000494:pharmacology*; D005260:Female; D006439:Hemodynamics / Q000187:drug effects*; D006801:Humans; D006975:Hypertension, Portal / Q000209:etiology*; D008103:Liver Cirrhosis / Q000150:complications* / Q000188:drug therapy* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D010919:Placebos; D011224:Prazosin / Q000008:administration & dosage / Q000494:pharmacology*; D013997:Time Factors
D000317:Adrenergic alpha-Antagonists; D010919:Placebos; D011224:Prazosin