Skip to main content
Intermediate Technical IVT

delirium

Pronunciation: dih-LEER-ee-um

An acute confusional state characterized by fluctuating consciousness and cognitive dysfunction in critically ill patients.

Full Definition

Delirium is a common and serious complication in surgical critical care, occurring in up to 80% of mechanically ventilated patients. It is characterized by acute onset of fluctuating disturbances in consciousness, attention, and cognitive function that develop over hours to days. Delirium presents as hyperactive (agitated), hypoactive (lethargic), or mixed subtypes, with hypoactive delirium being more common but often underrecognized. Risk factors include advanced age, pre-existing cognitive impairment, sedative medications, sleep deprivation, and severity of illness. Assessment tools like CAM-ICU (Confusion Assessment Method for ICU) enable systematic screening. Prevention strategies include early mobilization, minimizing sedation, optimizing sleep-wake cycles, and addressing modifiable risk factors.

Usage

Usage note: Distinguish between delirium (acute, reversible) and dementia (chronic, progressive) in documentation.

In Context

  • "CAM-ICU assessment revealed positive delirium requiring adjustment of sedation protocol." — Nursing assessment
  • "The patient developed hypoactive delirium on post-operative day 2, responding to environmental modifications." — Progress note

Also known as

acute confusional state ICU delirium

Don't confuse with

dementia sedation encephalopathy

Editors from these organisations have used our services since 1998

Reuters BBC Oxford University Press Penguin Random House Springer Microsoft Suncor Energy United Nations Fisher Investments IBM The Home Depot KODAK CHEVRON