Delirium in critically ill patients.

Delirium in the intensive care unit (ICU) is a common diagnosis, with an incidence ranging between 45% and 87%. Delirium represents a significant burden both to the patient and to the health care system, with a 3.2-fold increase in 6-month mortality and annual US health care costs up to $16 billion. In this review, the diagnosis, epidemiology, and risk factors for delirium in the ICU are discussed. The pathophysiology of delirium and evolving prevention and treatment modalities are outlined.