Confusion and delirium

Confusion and delirium are the most common behavioural disorders seen in an acute medical or surgical unit. Confusion can be regarded as a mild form of delirium and may give warning of the development of the more severe disorder. It causes an acute change of mental status, characterized by abnormal and fluctuating attention. It affects between 10 and 30% of medically ill patients, especially the elderly and often shortly after admission to hospital. It causes prolonged admission, increased morbidity and mortality, and delayed discharge, often culminating in long-term care. Its causation is reviewed and its prevention and management are described.