The RXc graph in evaluating and monitoring fluid balance in patients with liver cirrhosis.

A recent study, using height-standardized resistance (R/H) and reactance (Xc/H) and assuming a bivariate distribution, has proposed the "RXc graph". We applied this new approach for patients with chronic liver disease in differentiating various degrees of fluid unbalance. Our data showed that a 95% confidence ellipse of patients with chronic hepatitis (CH) overlapped that of healthy control subjects (CONTR), while those of patients with liver cirrhosis (CIR), patients with cirrhosis and ascites (ACIR), and patients with cirrhosis, edemas, and ascites (AECIR) were clearly different for both genders. A progressively shorter mean impedance vector proportional to the stage of liver disease and to the degree of fluid unbalance was found. The lower half of the 50% tolerance ellipse for the healthy population proved to be a threshold for cirrhotics, while almost all the subjects with clinically detectable edema fell outside this limit. The RXc graph was shown to be useful in monitoring the treatment of fluid unbalance and for the immediate selection of patients in whom BIA can precisely assess body composition.