Delirium Assessment in a Confused Elderly Patient
The Brief Confusion Assessment Method (bCAM) is the most appropriate cognitive assessment tool to assess for delirium in this 94-year-old nursing home patient presenting with acute confusion. 1, 2, 3
Rationale for Using the Brief Confusion Assessment Method (bCAM)
The bCAM is specifically designed for rapid delirium assessment in emergency settings and offers:
- High specificity (95.8-96.9%) and good sensitivity (78-84%) for delirium detection 1
- Brief administration time (under 5 minutes), making it practical for emergency department use
- Validation in elderly populations, including those with baseline cognitive impairment 2, 3
- Ability to distinguish delirium from other causes of cognitive impairment
How to Administer the bCAM
The bCAM evaluates four key features of delirium:
- Acute onset and fluctuating course: Confirm with nursing home staff that the confusion represents a change from baseline
- Inattention: Test by asking the patient to recite months of the year backward or perform digit span tests
- Altered level of consciousness: Assess if the patient is alert, vigilant, lethargic, or stuporous
- Disorganized thinking: Evaluate through simple questions and commands
A positive delirium diagnosis requires the presence of features 1 and 2, plus either feature 3 or 4.
Why bCAM is Superior to Other Options
- Beers Criteria: This is a medication appropriateness tool for elderly patients, not a cognitive assessment tool for delirium detection 4
- Buerger test: This evaluates peripheral arterial disease, not cognitive function
- Vestibular ocular motor screening: This assesses vestibular function and concussion symptoms, not delirium
- Standard CAM: While the full CAM is the gold standard, the bCAM is specifically adapted for emergency settings with comparable accuracy 1, 2
Clinical Implications
Early and accurate delirium detection is critical as:
- Missed delirium diagnosis can double mortality rates 5
- Delirium is associated with longer hospital stays and higher institutionalization rates 4
- Prompt identification enables investigation of underlying causes (infection, medication effects, metabolic disturbances) that may be reversible
Common Pitfalls to Avoid
- Mistaking baseline dementia for delirium: The bCAM helps distinguish between chronic cognitive impairment and acute delirium by focusing on acute changes and fluctuations 5
- Missing hypoactive delirium: Elderly patients often present with hypoactive rather than hyperactive delirium, which can be easily overlooked without formal assessment 5
- Inadequate history: Always obtain collateral information from caregivers about the patient's baseline cognitive status to identify acute changes 4
- Relying solely on orientation questions: These are insufficient to detect delirium; formal attention testing is essential 2
For this 94-year-old nursing home resident with acute confusion, the bCAM provides the most efficient and accurate approach to assess for delirium in the emergency department setting.