Long-latency event-related potentials in acute hepatitis patients with severe coagulopathy.

In 19 acute hepatitis patients with severe coagulopathy who were fully alert and oriented without any changes of mood or behavior, the P300 latency and the arterial blood ketone body ratio (KBR) were assessed as predictors of fulminant hepatitis. All 5 patients developing fulminant hepatitis had a corrected P300 latency longer than 345 msec and 4 of them had a KBR below 0.6. There was a significant negative correlation between the KBR and the blood ammonia level and between the KBR and the corrected P300 latency, while there was a positive correlation between the blood ammonia level and the corrected P300 latency. These data suggest that hepatic encephalopathy develops when loss of hepatic detoxifying activity allows toxic substances to reach the brain and induce cerebral edema. Our findings also suggest the clinical value of using the P300 latency combined with the KBR as predictors of fulminant hepatitis.