Confusion and delirium

Definition

Confusion is a loss of orientation (not knowing where, when, who and what you are), often combined with a loss of memory. Delirium is a short term state of confusion, accompanied with altered consciousness.

Epidemiology

Very common, especially in the elderly, or very ill.

Pathophysiology

As far as we can ascertain:

• If your body is a bit messed up, ie. electrolyte disturbance, infection etc, you get confused.
• If your brain isn't working properly, ie. alzheimer's disease, etc, you get confused.
• If your brain is getting squashed, ie. massive brain tumour or brain abscess, etc, you get confused.

Clinical and Associated Features

• Impaired cognitive function
• Hallucination
• Thought disturbances
• Aggression
• Agitation
• Retardation
• Sleep disturbance
• Mood disturbance

Dementia rears its ugly head

It's important to know the difference between dementia and delirium, although Lewy Body dementia can be misleading because it can fluctuate so wildly:

Dementia has a chronic onset. It is usually primary, and has a relatively constant state, worsening over months rather than hours.

Delirium has an acute onset, and is secondary to something else. It often causes sleep disturbance and affects consciousness levels, and fluctuates rapidly, over days rather than months.

Differential Diagnosis

• Sepsis
• Dementia
• Electrolyte disturbance
• Drug and alcohol abuse
• Stroke
• Alcohol withdrawal
• Trauma
• Brain cancer (either a brain tumour or a brain met)

Investigations

1. History, to screen for dementia and drug or alcohol abuse.
2. Septic screen.
3. CT scan of brain, to check for bleeds or clots.