What is Delirium?

Delirium is:

1. A neurologic emergency

2. Characterized by an acute change in attention and cognition

    • Develops over a short period of time
    • Fluctuates over the course of the day

3. Is an interplay between predisposing risk factors and precipitating factors

4. Has 3 main motoric subtypes

    • Hypoactive
    • Hyperactive
    • Mixed

Let's elaborate:

DSM-V. Arlington, VA: American Psychiatric Association; 2013

  • Delirium is characterized by disturbances in:
    • Attention
    • Awareness (reduced orientation to the environment)
    • Cognition (memory deficit, disorientation, language disturbance, perceptual disturbance)
  • Develops over a short period, is a change from baseline, and tends to fluctuate during the course of the day
  • Not explained by pre-existing, established, or evolving neurocognitive disorder
  • Evidence from HPI, PE, or lab tests that disturbance is a physiologic consequence of medical condition, intoxicating substance, and/or medication use


DSM-V. Arlington, VA: American Psychiatric Association; 2013
Han JH, et al. Acad Emerg Med. 2009;16(3):193–200


ED, emergency department

HPI, history of present illness

PE, pulmonary embolism