Clinical Reference

FOR DOCTORS & CAREGIVERS

Clinical tools, screening protocols, and differential diagnosis guidance to help you catch delirium before it becomes a crisis.

70%

of delirium cases missed by clinical staff

CAM

gold-standard bedside screening tool

< 5 min

to complete a CAM assessment

WHY DELIRIUM GETS MISSED

Delirium is the most common acute neuropsychiatric syndrome in hospitalized older adults, and the most under-recognized. Hypoactive delirium, which presents as withdrawal, quiet confusion, or apparent depression, is missed in up to 70% of cases. Misdiagnosis leads to inappropriate sedation, delayed treatment of the underlying cause, prolonged hospitalization, and significantly increased mortality.

Hypoactive Presentation

Quiet, withdrawn, or 'cooperative' patients are often assumed to be stable. This is the most dangerous missed presentation.

Dementia Overlap

Patients with pre-existing dementia are at highest risk for delirium and are most often misdiagnosed — the two conditions can and do coexist.

Atypical Symptoms

In older adults, delirium may present without classic agitation. Subtle changes in attention, sleep-wake cycle disruption, and psychomotor slowing are key signals.

THE CONFUSION ASSESSMENT METHOD (CAM)

The CAM is the most validated bedside tool for delirium diagnosis. A positive CAM requires Features 1 AND 2, plus either Feature 3 OR Feature 4.

Acute Onset & Fluctuating Course

Required

Is there evidence of an acute change in mental status from the patient's baseline? Does the behavior fluctuate during the day — tending to come and go or increase and decrease in severity?

Inattention

Required

Does the patient have difficulty focusing attention — for example, being easily distracted or having difficulty keeping track of what was being said?

Disorganized Thinking

Is the patient's thinking disorganized or incoherent, such as rambling or irrelevant conversation, unclear or illogical flow of ideas, or unpredictable switching from subject to subject?

Altered Level of Consciousness

Overall, how would you rate this patient's level of consciousness? Any rating other than 'alert and normal' — vigilant, lethargic, stuporous, or comatose — is considered abnormal.

CAM POSITIVE = Features 1 + 2 + (3 or 4). A positive result requires immediate workup for underlying cause.

The full CAM instrument with scoring instructions is available from the Hospital Elder Life Program (HELP) at helpdesk.agingbraincare.org

DIFFERENTIAL DIAGNOSIS

Delirium must be distinguished from dementia, depression, and primary psychiatric disorders. Key differentiators:

Characteristic	Delirium	Dementia	Depression
Disease Progression	Hours to days	Months to years	Weeks to months
Cognition	Globally impaired, fluctuates	Stable decline, memory-first	Patchy, effort-dependent
Attention	Always impaired	Preserved early	May be impaired
Consciousness	Altered	Normal until late	Normal
Reversible?	Yes, with treatment	No	Often, with treatment

INITIAL WORKUP WHEN DELIRIUM IS SUSPECTED

Once CAM is positive, the goal is rapid identification of the underlying cause. Common reversible causes include:

Infection

UTI, pneumonia, sepsis, meningitis — UTI is the single most common trigger in older women

Medications

Anticholinergics, benzodiazepines, opioids, polypharmacy interactions, recent medication changes

Metabolic

Hyponatremia, hypoglycemia, thyroid dysfunction, hepatic or renal failure, dehydration

Neurological

Stroke, subdural hematoma, seizure (post-ictal), CNS infection

Cardiac / Pulmonary

Hypoxia, hypotension, MI, PE, heart failure exacerbation

Pain / Retention

Uncontrolled pain, urinary retention, fecal impaction — often overlooked in non-verbal patients

Labs:Minimum initial labs: CBC, BMP, LFTs, TSH, urinalysis with culture, blood cultures if febrile, chest X-ray. Consider CT head if focal neuro signs or fall history.

PREVENTION & NON-PHARMACOLOGICAL MANAGEMENT

The HELP (Hospital Elder Life Program) protocol reduces delirium incidence by up to 40% through targeted non-pharmacological interventions.

Orientation

Reorient patient to time, place, and situation at every interaction. Visible clocks and calendars. Consistent caregivers.

Sensory Optimization

Ensure hearing aids and glasses are in place. Adequate lighting during the day. Minimize unnecessary noise.

Sleep Protocol

Protect nighttime sleep. Avoid waking for non-urgent vitals. Minimize nighttime light and noise. No sedatives.

Early Mobilization

Get the patient out of bed as soon as medically safe. Prolonged bed rest is an independent delirium risk factor.

Hydration & Nutrition

Dehydration is a major precipitant. Monitor fluid intake. Encourage oral hydration. Nutritional support as needed.

Avoid High-Risk Medications

Review the Beers Criteria. Avoid anticholinergics, benzodiazepines, and unnecessary sedatives in older adults.

COMMUNICATING WITH FAMILIES

Families are your most valuable diagnostic resource. They know the patient's baseline. Engage them early and specifically.

Ask families directly: 'Is this how they normally think and act?' A family member saying 'this isn't like them' is a clinical signal.

Explain that delirium is not dementia and is not permanent. Fear of permanent cognitive loss causes families to accept delirium as 'normal aging.'

Invite family presence during assessments. Familiar faces and voices reduce agitation and improve cooperation.

Give families a role: reorientation, hydration encouragement, bringing familiar objects from home. Involvement reduces helplessness and improves outcomes.

CLINICAL RESOURCES

Evidence-based tools, validated screening instruments, and clinical guidelines for delirium assessment and management.

View Resources & References