Cirrhotic patients may exhibit circulatory derangement and renal dysfunction during the
clinical course. Renal dysfunction in cirrhosis can occur without speific causative factors. This
functional renal failure in cirrhosis is considered as a consequence of renal vasoconsitriction.
These alterations of renal hemodynamics are already present in the early phase of the
disease, even in the condition that the conventional kidney function tests are normal. A new
method for noninvasive evaluation of arterial tone is duplex Doppler sonography. Among the
various sonographic indices proposed, the renal resistive index(RI) is the most widely used for
the estimation of intrarenal arteriolar vascular resistance.
This study was performed to evaluate the role of Doppler sonography in early detection of
renal dysfunction and to assess the clinical significance of RI. In 25 cirrhotic patients without
overt kidney failure and ten control subjects, the RI of the arcuate artery in both kidneys
was measured by Doppler sonography. The mean RI of cirrhotic group was significantly
higher than that of control subjects(0.68±0.08 vs. 0.62±0.06, p<0.05). According to Child
class, the RI showed increasing tendency from A to C, though without statistical significance.
In this study, the RI was significantly inversely correlated with 24hr urinary sodium
amount(r=-0.39, p<0.05) and correlated with serum creatinine(r=0.60, p<0.01). This study
indicates that the measurement of RI is a sensitive method to assess intrarenal hemodynamics
and to detect early changes of the renal dysfunction in cirrhotic patients.
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