Delirium, not to be confused with dementia.

The DSM criteria for delirium:

1. Disturbance of consciousness
2. Change in cognition
3. Develops over a short period of time (hours to days) and fluctuates
4. There is an identifiable general medical condition (or is substance induced)

It is important to recognize a delirium so that the underlying condition can be treated. It is also important because the delirium itself can be harmful to the patient, for example if someone who is delirious walks out into the cold with only a housecoat.

The longer one has delirium, the longer is takes to resolves, even after the underlying condition is treated.

If someone asks you to asses the level of competency of a person with delirium, it’s best to defer. Competency is both TIME- and QUESTION-dependent, so if you are asking someone when they are lucid, they could still be deemed competent, even if they are likely going to return to being delirious.

Mnemonic for delirium: I WATCH DEATH

1. Infectious: UTIs, pneumonia, meningitis
2. Withdrawal: alcohol, benzos
3. Acute metabolic: liver or kidney failure, electrolytes
4. Trauma: post-op, head injury
5. CNS pathology: tumor, stroke, seizure
6. Hypoxia: anemia, PE, heart failure
7. Deficiencies in vitamins: thiamine, B12, folate
8. Endocrine: Glucose, thyroid, adrenal, parathyroid (hypercalcemia)
9. Acute vascular: shock, hypertensive ecephalopathy
10. Toxins: alcohol, benzos, anticholinergics, opioids, anesthetics, anticonvulsants, dopaminergic agents, steroids, insulin, antibiotics (quinolines), NSAIDs
11. Heavy metals: lead, arsenic, mercury

Work up

Standard

1. CBC, BUN, Creatinine
2. Extended electrolytes (Na, K, HCO3, Ca, PO, Mg)
3. Glucose
4. Liver function tests
5. Albumin
6. Urine culture
7. TSH
8. Vitamin B12 & folate

And maybe

• ECG
• CXR
• Blood cultures
• CT head
• Heavy metal screen
• VDRL, HIV
• Lumbar puncture
• EEG

But I want to earn the radiologist tons of money…
Only if they have:

• Focal neurological deficit
• Acute change in status
• Anticoagulant use
• Acute incontinence
• Gait abnormality
• History of cancer