Delirium

Abstract

For hundreds of years it has been recognised that some individuals with physical illness experience a sudden and frightening deterioration in their mental functioning. The condition has variably been known as ‘acute confusional state’ or ‘acute brain failure’ among others; however, the name by which it is best known is delirium from the Latin ‘delire’, meaning deranged. Delirium is a common condition, which most doctors will encounter during their professional lives and thus knowledge of its features and management is important. It is a neuropsychiatric syndrome that is characterised by disturbances in a wide variety of domains, particularly areas such as consciousness, orientation and perception. It is a distressing experience, not only for the patient and staff involved, but also for the individual’s relatives. Effective management and identification of those at risk of the condition can help improve outcomes such as prolonged hospital admissions. Both the British Geriatrics Society and the National Institute for Health and Care Excellence have produced guidance regarding how delirium should be identified and managed. This article summarises an approach to assessment, investigation and management for primary care clinicians.