Correlation between Electroencephalogram, Hepatic Encephalopathy Grade, and Biochemical Indices in Beagles with Portacaval Anastomosis

The EEG, grades of hepatic encephalopathy, and biochemical indices of 16 beagles with portacaval anastomosis were recorded throughout their lives and correlations between these parameters were investigated. The degree of deterioration of some biochemical indices, such as the ammonia concentration, glutamate oxaloacetate transaminase and alkaline phosphatase activities in the plasma, and percentage loss of body weight showed a progressive increase parallel to the severity of the hepatic encephalopathy (HE) grade (grading scale 0-IV), but other biochemical indices such as the concentrations of aromatic or branched-chain amino acids, the molar ratio of branched-chain to aromatic amino acids, or the total protein concentration in the plasma did not show such relationship. The SW ratio, an index of the incidence of slow-waves in the EEG, was calculated from frequency distribution histograms which were obtained by frequency analyses of EEG recordings. A slight but significant correlation was found between the S...