REVERSIBILITY OF HEPATORENAL-SYNDROME BY PROLONGED ADMINISTRATION OF ORNIPRESSIN AND PLASMA-VOLUME EXPANSION

Hepatorenal syndrome is caused by a marked vasoconstriction of the ren al circulation, It is suggested that the renal vasoconstriction is rel ated to an overactivity of vasoconstrictor systems secondary to a vaso dilation of the arterial circulation that causes a reduction in effect ive arterial blood volume, To test this hypothesis, 16 cirrhotic patie nts with hepatorenal syndrome were treated with a combination of ornip ressin, a potent vasoconstrictor agent, and plasma volume expansion wi th albumin to improve effective arterial blood volume. The combined tr eatment was administered either for 3 or 15 days (8 patients each), an d the effects on renal function, vasoactive systems, and systemic hemo dynamics were assessed, The 3-day treatment with ornipressin and album in was associated with a normalization of the overactivity of renin-an giotensin and sympathetic nervous systems, a marked increase in atrial -natriuretic peptide levels, and only a slight improvement in renal fu nction, However, when ornipressin and albumin were administered for 15 days, a remarkable improvement in renal function was observed, with n ormalization of serum-creatinine concentration, a marked increase in r enal plasma flow and glomerular filtration rate, and a persistent supp ression in the activity of vasoconstrictor systems, However, 3 of 8 pa tients on 15-day therapy treatment had to be discontinued because of i schemic complications. In conclusion, the decrease in effective arteri al blood volume and the activation of vasoconstrictor systems play a c rucial role in the pathogenesis of hepatorenal syndrome. Although the prolonged administration of ornipressin combined with plasma volume ex pansion reverses hepatorenal syndrome, this treatment should be used w ith great caution in clinical practice because of the risk of ischemic complications.