Although arterial vasodilation is a well-known feature in patients with cirrhosis, the venous system remains unexplored. To measure total effective vascular compliance, a reflection of the properties of the venous system, rapid volume expansion (300 ml of a gelatin solution in 3 min) was performed in 23 patients. Eleven patients had compensated cirrhosis (Child-Pugh grade A or B), and eight had decompensated cirrhosis (Child-Pugh grade C). Four control patients had mild chronic hepatitis, normal hepatic venous pressure and normal liver architecture. Cardiac index, hepatic venous pressures, hepatic and azygos blood flow and renal plasma flow were measured before and immediately after volume expansion. Right atrial pressure was recorded during volume expansion. This allowed the calculation of total effective vascular compliance, which was higher in patients with decompensated cirrhosis than in those with compensated cirrhosis (4.65 +/- 4.21 vs. 1.34 +/- 0.63 ml.mm Hg-1.kg-1; p less than 0.05). In response to volume expansion, renal vascular resistance decreased significantly in patients with compensated cirrhosis, but not in those with decompensated cirrhosis (-30% +/- 33% vs. +2% +/- 23%; p less than 0.05). No change was seen in glomerular filtration rate. Systemic oxygen consumption increased in patients with compensated cirrhosis, but not in those patients with decompensated cirrhosis (25% +/- 33% vs. -4% +/- 9%; p less than 0.05). Although in all patients with cirrhosis volume expansion increased central venous pressures, azygos blood flow and the hepatic venous pressure gradient did not change.(ABSTRACT TRUNCATED AT 250 WORDS)