Acid-base disturbance in patients with fulminant hepatic failure.

Forty-two arterial blood pH and gas determinations were carried out on 11 patients with fulminant hepatic failure. The most common type of acid-base disturbance was that of respiratory alkalosis in 22 cases (52.4%). This was partially compensated in 13 subjects (31.0%) while an accompanying metabolic alkalosis was present in 9 (21.5%). Partially compensated metabolic acidosis was observed on 15 occasions (35.7%), all of which were in patients with laboratory evidence of impaired renal failure. The mental status of the patients was evaluated in each of the categories of acid-base disturbances. Some degree of correlation was evident between the PCO2 and the magnitude of base excess and that of the severity of the encephalopathy. The lower PCO2 and greater negative base excess values tended to be nearly always present in totally comatose subjects. By contrast, there was no clear cut relationship between pH and mental state.