Screening for delirium within intensive care units in scotland: a national survey

Delirium is defined by the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) as a disturbance in consciousness and alteration in cognition over a short time period. It tends to fluctuate throughout the day and is evident from the clinical history, examination or investigations that delirium is as a result of a medical condition, drug withdrawal or intoxication. All of the above factors need to be present for a diagnosis of delirium to be made.¹