DIAGNOSIS OF FUNCTIONAL KIDNEY FAILURE OF CIRRHOSIS WITH DOPPLER SONOGRAPHY - PROGNOSTIC VALUE OF RESISTIVE INDEX

Time-velocity wave-form analysis of Doppler signals from small intrare nal arteries allows estimation of intrarenal arteriolar vascular resis tance. Among the various indexes proposed, the resistive index is the most widely used for this estimation. To investigate whether the resis tive index is useful in the diagnosis of functional kidney failure and prediction of survival in cirrhotic patients with ascites, we measure d resistive index, kidney and liver function and plasma levels of reni n, aldosterone and antidiuretic hormone in 10 healthy subjects, 12 pat ients with compensated cirrhosis and 32 patients with cirrhosis and as cites (17 with kidney failure). A total of 28 clinical and laboratory variables were analyzed for prognostic value. Resistive index was sign ificantly increased in patients with kidney failure (0.74 +/- 0.01) co mpared with those in the other three groups (0.64 +/- 0.01, 0.64 +/- 0 .02 and 0.67 +/- 0.01) and correlated significantly with glomerular fi ltration rate, arterial pressure, plasma renin activity and free water clearance in the cirrhotic patients, The sensitivity and specificity of the resistive index in detecting kidney failure in patients with as cites were 71% and 80%, respectively. Nine variables were correlated w ith survival in the univariate analysis, including resistive index, ag e, hepatomegaly, blood urea nitrogen, serum creatinine, plasma sodium concentration, glomerular filtration rate, plasma renin activity and p lasma concentration of antidiuretic hormone. Multivariate analysis dis closed only three independent predictors of survival: plasma renin act ivity, plasma concentration of antidiuretic hormone and serum sodium c oncentration. In conclusion, resistive index is a sensitive method to assess intrarenal hemodynamics in patients with cirrhosis and ascites. It also has predictive value for survival in these patients.