Based on the “West Haven criteria,” hepatic encephalopathy (HE) is classified into the following stages:
| Stage | Description | Psychometric test procedures* |
| 0 (minimum HE) | Asymptomatic; no clinical neurological symptoms, but deficits in cognitive subdomains such as attention, fine motor skills, short-term memory, visuospatial perception | pathological (pathological) |
| I | Onset of drowsiness, poor concentration, sleep disturbances, mood swings, slowing down, slurred speech, confusion | Pathological |
| II | Apathy, flutter tremor (coarse tremor of hands), greater drowsiness; changes in writing samples, EEG: triphasic waves | Pathological |
| III | Flutter tremor, patient predominantly asleep but can be awakened; corneal reflexes (eyelid closure reflex) and tendon reflexes preserved; onset of smell of raw liver (“foetor hepaticus”); EEG: triphasic waves | no longer possible |
| IV | Hepatic failure coma (coma hepaticum): no more response to painful stimuli, no corneal reflexes, marked foetor hepaticus, flutter tremor usually absent, deep sleep, unable to awaken; EEG: delta activity | no longer possible |
22-74% of patients with liver cirrhosis already have “minimal hepatic encephalopathy” (synonym: latent (hidden) hepatic encephalopathy).
* Psychometric test procedures = number-connection test, line-tracing test, number-symbol test; They serve as parameters for concentration ability, fine motor skills as well as logical thinking.
