An elderly patient arrives confused. Family says they’re “not themselves.” The rookie dilemma: Is this delirium or dementia? Getting it wrong can mean missing sepsis or discharging someone unsafe. Here’s how to tell the difference quickly in the ED.
Why It Matters
- Delirium = acute, reversible emergency.
- Dementia = chronic, progressive condition.
- Many patients with dementia can still develop superimposed delirium — making it even harder to spot.
Key Differences Between Delirium and Dementia
| Feature | Delirium | Dementia |
|---|---|---|
| Onset | Acute (hours–days) | Chronic (months–years) |
| Course | Fluctuating, worse at night (“sundowning”) | Steady decline |
| Consciousness | Reduced, drowsy or hyperalert | Usually clear until late |
| Attention | Impaired (easily distractible) | Usually preserved early |
| Memory | Poor immediate recall | Poor recent memory, remote memory preserved |
| Reversibility | Often reversible if cause treated | Usually irreversible |
| Common Causes | Infection, hypoxia, meds, metabolic | Alzheimer’s, vascular, Lewy body, FTD |
Rookie pearl: Delirium = problem with attention. Dementia = problem with memory.
Step 1: Recognize Delirium in the ED
- Fluctuating confusion, disorganized thinking.
- Inattention (cannot spell “WORLD” backwards, cannot follow simple tasks).
- Altered sleep–wake cycle.
- Hallucinations or paranoia.
- Rapid onset (family: “they were fine yesterday”).
Step 2: Common Causes of Delirium (Think “PINCH ME” Mnemonic)
- Pain.
- Infection (UTI, pneumonia, sepsis).
- Nutrition (dehydration, electrolytes).
- Constipation/urinary retention.
- Hypoxia.
- Medications (benzos, anticholinergics, opioids).
- Environment (restraint, sensory deprivation).
Step 3: ED Workup
- Vitals + glucose immediately.
- Labs: CBC, electrolytes, renal, LFTs, UA, cultures if indicated.
- CXR if pneumonia suspected.
- ECG (arrhythmias, ischemia).
- CT head if trauma, focal neuro signs, or no clear cause.
- Medication review — one of the most common culprits.
Step 4: Management
- Treat underlying cause — infection, hypoxia, dehydration, medication toxicity.
- Supportive: quiet environment, reorientation, adequate lighting, family presence.
- Avoid physical restraints if possible.
- Medications: only if severe agitation threatens safety — low-dose haloperidol or atypical antipsychotics. Avoid benzos unless alcohol withdrawal suspected.
Step 5: Disposition
- Admit delirium unless fully reversible cause treated in ED and safe follow-up possible.
- Dementia patients may go home if at baseline, safe environment, no acute issues.
Common Rookie Mistakes
- Assuming all elderly confusion = dementia.
- Missing infection as cause of delirium (esp. UTI or pneumonia).
- Overusing sedatives/benzos — worsen delirium.
- Discharging delirious patient home without treating cause.
Rookie Pearls
- Rapid onset = delirium. Slow decline = dementia.
- Always ask family/caregivers about baseline.
- Delirium is common in elderly — up to 30% of inpatients.
- A delirious patient in the ED is unstable until proven otherwise.
Take-Home Message
For rookies:
- Delirium is acute, reversible, and dangerous.
- Dementia is chronic, progressive, but patients can get delirium on top of it.
- Always rule out reversible causes of delirium before attributing confusion to dementia.
Remember: In the ED, a confused elder is delirium until proven otherwise.
Leave a Reply