Postprandial changes inportal haemodynamics in patients withcirrhosis

Previous studies haveshownthatportal venous pressureincreases in patients with cirrhosis after a protein meal.Sincethisincrease may bemediated byan increase in hepatic bloodflow or postsinusoidal hepatic vascular resistance, thepresentstudy was designed to examinetheprecise relation betweenthepostprandial changes inthese three variables inpatients withcirrhosis and portal hypertension. Estimated hepatic blood flow(EHBF;indocyanine green clearance), portosystemic gradient (PSG;wedgedfree hepatic venous pressure), andpostsinusoidal hepaticvascular resistance (PSR=PSG/ EHBF)were measured simultaneously before andat10minute intervals after a highprotein meal,containing 80g protein, 40g carbohydrate and12gfat(600kcal) inninepatients (sevenalcoholic, twonon-alcoholic) withcirrhosis andportal hypertension. After themeal, theportosystemic gradient increased by33% frommean (SEM)15*6(0.9) mm Hgto20*7 (1.3) mm Hg,(p<001;Wilcoxon signed ranks test) within 30minutes. Coincident withthis increase inportosystemic gradient, estimated hepatic bloodflowincreased by69-2%from 20x1(1.7) mUmin/kg to33-9(2.5) mUmin/kg (p=0.01), peakvalues occurring at25minutes, at whichtimethepostsinusoidal hepatic vascular resistance haddecreased by31%from 110(0.1) 10'2 mm Hg/mUminto0x8(0.5) 10'2 mm Hg/mUmin(p=001). Theseresults suggest that thepostprandial increase inportal venous pressureinpatients withcirrhosis is mediated byan increase inhepatic blood flow andmodified bya simultaneous decrease in postsinusoidal resistance.