(Science: neurology, psychiatry) An acute, reversible organic mental disorder characterised by reduced ability to maintain attention to external stimuli and disorganised thinking as manifested by rambling, irrelevant or incoherent speech.
there are also a reduced level of consciousness, sensory misperceptions, disturbance of the sleep wakefulness cycle and level of psychomotor activity, disorientation to time, place or person and memory impairment.
delirium may be caused by a large number of conditions resulting in derangement of cerebral metabolism, including systemic infection, poisoning, drug intoxication or withdrawal, seizures or head trauma and metabolic disturbances such as hypoxia, hypoglycaemia, fluid, electrolyte or acid base imbalances or hepatic or renal failure.
Synonym: acute confusional state, acute brain syndrome.
Origin: L. Lira = furrow or track, i.e., off the track