LOOP DIURETIC THERAPY IN LIVER-CIRRHOSIS WITH ASCITES

Medical treatment of ascites is aimed at reverting sodium retention, t hat is, at creating a negative sodium balance to relieve ascites. Bed rest and low-sodium diet induce the disappearance of ascites in about 10% of patients. Loop diuretics and aldosterone antagonists must be ad ministered to the patients not responding to the previous regimen. Ava ilable evidence indicates that aldosterone antagonists are the first-c hoice drugs, as these substances are more effective than furosemide. N evertheless, loop diuretics potentiate the effects of aldosterone anta gonists. The reduced efficacy of furosemide in these patients, when co mpared with that of spironolactone, may be related to an impairment of both pharmacodynamics and pharmacokinetics. In fact, most sodium not reabsorbed in Henle's loop, due to the action of furosemide, is subseq uently taken up in the distal nephron because of hyperaldosteronism. A further mechanism of resistance may be related to an impaired excreti on of furosemide into the tubular lumen. The use of diuretics in the t reatment of ascites is associated with several side effects, including prerenal azotemia, hepatic encephalopathy, and electrolyte and acid-b ase disorders. A stepped-care approach, together with careful monitori ng of patients, is the best way to reduce the incidence of these compl ications. Ethacrynic acid has been shown to be highly effective in the treatment of ascites, even in patients refractory to other diuretics, but its use is associated with a high incidence of hypokalemia and hy pochloremic alkalosis. Bumetanide and piretanide are comparable to fur osemide, in terms of both efficacy and side effects. Recent data sugge st that torasemide, administered in equipotent doses to furosemide, ex erts a higher natriuretic and diuretic effect, together with a similar kaliuretic effect.