Serum octopamine, coma, and charcoal haemoperfusion in fulminant hepatic failure

Serum octopamine levels were significantly higher in twenty patients with fulminant hepatic failure (FHF) during the first 48 h of grade IV coma than in health control subjects (3.38 +/- 0.20 ng/ml and 1.75 +/- 0.19 ng/ml respectively, P less than 0.001). Serial measurements in five patients who died without regaining consciousness showed serum octopamine to remain raised, and concentrations in the cerebrospinal fluid at death reflected serum levels. In five patients who regained consciousness, improvement in encephalopathy was associated with a significant reduction in serum octopamine. Renal failure in patients with FHF was found to contribute to raised serum octopamine but could not alone account for the observed levels. Patients given neomycin therapy did not have significantly lower serum octopamine levels than an untreated group. There was, however, a significant correlation between elevated serum octopamine and the occurrence of gestrointestinal bleeding during the previous 24 h. Charcoal haemoperfusion did not appreciably reduce serum octopamine levels.