Initial Workup and Management for Altered Mental Status in Elderly
The initial workup for altered mental status in elderly patients should include a comprehensive evaluation for delirium using validated screening tools, targeted laboratory testing, and neuroimaging when indicated, with immediate focus on identifying and treating reversible causes such as infections, medication effects, and metabolic disturbances. 1, 2
Immediate Assessment
Differentiate Delirium from Dementia
| Feature | Delirium | Dementia |
|---|---|---|
| Onset | Acute | Insidious |
| Course | Fluctuating | Constant |
| Attention | Disordered | Generally preserved* |
| Consciousness | Disordered | Generally preserved* |
| Hallucinations | Often present | Generally absent* |
*Variable in advanced dementia
Validated Screening Tools
- Use a two-step process 1:
- Highly sensitive delirium triage screen
- Brief Confusion Assessment Method (CAM)
- Richmond Agitation-Sedation Scale
- Glasgow Coma Scale for severity quantification 2
Essential Laboratory Workup
First-line laboratory tests 2:
- Complete blood count (CBC)
- Basic metabolic panel (BMP)
- Liver function tests
- Urinalysis
- Blood cultures (if febrile)
- Thyroid function tests
- Medication levels when appropriate
Additional testing based on clinical suspicion:
- Toxicology screen
- Blood gases
- Ammonia level
- Vitamin B12 level
Imaging Studies
- Head CT without contrast - first-line neuroimaging 2
- Brain MRI - when clinical picture is unclear, presentation is atypical, or abnormal findings on examination 2
- Indications for neuroimaging 2:
- Focal neurological deficits
- Abnormal neurological examination
- First-episode psychosis without clear psychiatric cause
- New or worsening headaches
- History of head trauma
- Suspected stroke, seizure, or intracranial infection
- Altered level of consciousness
Additional Diagnostic Considerations
- Electroencephalography (EEG) - to rule out nonconvulsive seizures 2, 3
- Lumbar puncture - when infection or autoimmune encephalitis is suspected 2, 4
Management Approach
Treat Underlying Causes
- Common etiologies to address 2, 5:
- Neurological (35%)
- Toxicological/medication-related (23%)
- Systemic/organic (14.5%)
- Infectious (9.1%) - especially UTI and pneumonia
- Endocrine/metabolic (7.9%)
- Psychiatric (3.9%)
- Traumatic (2.1%)
Supportive Care
- Maintain normothermia
- Ensure adequate oxygenation and perfusion
- Provide reorientation strategies
- Avoid physical restraints when possible 1, 2
Management of Agitated Delirium
Non-pharmacological approaches first 1, 4:
- Eliminate identified risk factors
- Foster orientation (clocks, calendars, caregiver identification)
- Ensure adequate pain control
- Use sensory aids as appropriate
- Regulate bowel/bladder function
- Provide adequate nutrition
- Increase supervised mobility
Pharmacological interventions - only when non-pharmacological approaches fail 4
Common Pitfalls to Avoid
- Attributing confusion solely to age or pre-existing dementia - always search for acute, reversible causes 2
- Overlooking hypoactive delirium - presents with cognitive and motor slowing rather than agitation; associated with greater morbidity and mortality 2
- Assuming bacteriuria equals UTI - asymptomatic bacteriuria is common in elderly and should not be treated based on confusion alone 2
- Overreliance on laboratory testing - use tests to complement, not replace, thorough clinical assessment 2
- Failing to reassess - mental status changes may wax and wane; delirium screening should be reevaluated regularly 1
Prognosis
- Overall mortality rate in patients with AMS is approximately 8.1% 5
- Mortality is significantly higher in elderly patients (10.8% vs. 6.9% in younger patients) 5
- Delirium is a medical emergency with mortality twice as high if left undiagnosed 2
Remember that altered mental status in elderly patients represents a medical emergency requiring prompt evaluation and treatment to decrease morbidity and mortality.