Standardised nomenclature associated with acquired acute cognitive dysfunction
| Name | Definition | Time course | Cause |
|---|---|---|---|
| Acute encephalopathy | Change from baseline cognitive status. | Rapidly developing (<4 hours). | Pathobiological process in the brain. |
| Delirium | Disturbance in attention, cognition and awareness, not explained by another neurocognitive disorder or reduced level of arousal. | Hours to few days. Tends to fluctuate. | Direct physiologic consequence of another medical condition, intoxication, withdrawal, toxin exposure or multiple aetiologies. |
| Coma | Severely depressed responsiveness. | Variable. | May follow acute encephalopathy or delirium. |