Psychiatry – Delirium: By Mark Oldham M.D.

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Psychiatry – Delirium
Whiteboard Animation Transcript
with Mark Oldham, MD
https://medskl.com/Module/Index/delirium

Delirium is a state of acute mental confusion. It can be caused by medical conditions or the psychoactive effects of medication or other substances. Unlike the terms encephalopathy and altered mental status, which also describe confusional states, delirium has a clear, reliable definition. As such, it is the preferred term when a patient meets diagnostic criteria.

Delirium is a clinical diagnosis. Imaging studies and laboratory tests cannot diagnose delirium itself, but may establish a cause of delirium.

Delirium diagnosis requires an acute change in mental status from baseline, characterized by:

Impaired attention.
Poor awareness of one’s surroundings.
Often a fluctuating course throughout the day.

It also requires evidence of cognitive impairment such as amnesia, disorientation, disorganized thoughts, delusions, or hallucinations; as well as a Medical or substance-induced cause.

Delirium is categorized based on psychomotor activity. It can be:

Hypoactive: with sluggishness and impoverished thinking;
Hyperactive: with agitation and intense emotions; or
Mixed level of activity: including combinations of the other two.

Delirium is a medical diagnosis, not a mental illness. It can present with depression, anxiety, or psychosis, but these typically improve when delirium resolves.

Certain risk factors, such as advanced age or cognitive impairment, may predispose a person to developing delerium. Often, multiple risk factors will be found.


Common delirium causes, or precipitants, include medications (especially anticholinergics and benzodiazepines), urinary tract infection, pneumonia, bacteremia, inflammation after major surgery, decompensated cirrhosis, hyponatremia, and hypoglycemia.

Delirium is often preventable. Preventive strategies include:

Avoiding or limiting deliriogenic medications.
Non-pharmacological interventions for healthy sleep.Good nutrition and hydration.
Correcting hearing and visual impairment, as well as cognitive and interpersonal stimulation.

The primary treatment of delirium, involves addressing the underlying cause or causes. Benzodiazepines, which often worsen or prolong delirium, should be avoided (except in alcohol withdrawal delirium), and neuroleptics reserved for agitation or distressing psychological symptoms. Delirium tends to improve – in most cases, resolve entirely – once its cause are addressed.