What is the initial approach to a patient presenting with delirium?

Initial Approach to Delirium Workup

The initial approach to a patient presenting with delirium should include identification of predisposing and precipitating factors through a comprehensive assessment, with particular focus on medication review, infection, metabolic abnormalities, and neurologic causes. 1

Diagnosis and Assessment

• Delirium diagnosis should be made by a trained healthcare professional using clinical assessment based on DSM or ICD criteria 1
• When cognitive or behavioral changes suggestive of delirium are present, a formal clinical assessment should be performed to confirm the diagnosis 1
• Distinguish delirium from dementia by assessing:
  • Onset (acute in delirium vs. insidious in dementia)
  • Course (fluctuating in delirium vs. constant in dementia)
  • Attention (disordered in delirium vs. generally preserved in dementia)
  • Consciousness (disordered in delirium vs. generally preserved in dementia) 1

Initial Workup

History and Examination

• Assess for recent changes or fluctuations in cognitive function, behavior, or physical function 1
• Evaluate for sentinel changes including impaired concentration, slow responses, withdrawal, sleep disturbances, hallucinations, confusion, agitation, or mood changes 1
• Perform a complete neurological examination with special attention to level of consciousness, attention, and cognition 1

Laboratory Investigations

• Complete blood count to assess for infection 1
• Comprehensive metabolic panel to evaluate electrolytes, renal function, liver function 1
• Urinalysis to rule out urinary tract infection 1
• Blood glucose measurement 1
• Medication levels when appropriate (e.g., digoxin, anticonvulsants) 1
• Consider blood cultures if infection is suspected 1
• Evaluate for hypercalcemia, hypomagnesemia, and SIADH as these are common metabolic causes 1

Imaging

• CT head without IV contrast is usually appropriate as the initial imaging test for new onset delirium 1
• MRI head without and with IV contrast may be appropriate when there is suspicion for intracranial process requiring intervention 1
• The yield of neuroimaging may be low in the absence of focal neurologic deficit or trauma 1

Evaluation of Common Precipitating Factors

Medications

• Review all medications with special attention to:
  • Vasodilators
  • Diuretics
  • Antipsychotics
  • Sedative/hypnotics
  • Anticholinergics 1
• Consider opioid-induced neurotoxicity, especially in cancer patients 1

Infections

• Evaluate for common infections including:
  • Urinary tract infection
  • Pneumonia
  • Sepsis 1
• Treat identified infections if consistent with patient's goals of care 1

Metabolic Abnormalities

• Assess for:
  • Electrolyte disturbances (particularly sodium, calcium, magnesium)
  • Hypoglycemia or hyperglycemia
  • Acid-base disorders
  • Renal or hepatic dysfunction 1

Management Approach

Non-pharmacological Interventions

• Reorient the patient frequently 2
• Ensure adequate hydration 2
• Promote early mobilization when appropriate 2
• Maintain normal sleep-wake cycles 1
• Provide appropriate sensory aids (glasses, hearing aids) 1
• Create a calm, well-lit environment 1

Pharmacological Management

• Pharmacological interventions should be limited to patients with distressing symptoms or safety concerns 1
• Medications should be used at the lowest effective dose and for the shortest time possible 1
• Evidence does not support routine use of haloperidol or risperidone for mild-to-moderate delirium 1
• Benzodiazepines should be reserved for alcohol or benzodiazepine withdrawal delirium or for severe symptomatic distress 1

Special Considerations

Imaging Challenges

• Patients with delirium may have difficulty following commands or remaining still for imaging studies 1
• Coordination with family members and managing physicians may be critical for successful diagnostic imaging 1

Education

• Interprofessional delirium education should be part of a unit- or hospital-wide strategy to improve recognition and management 1

Clinical Pitfalls to Avoid

• Failing to perform routine cognitive assessment in high-risk patients, particularly elderly hospitalized patients 3
• Mistaking delirium for dementia or psychiatric disorders 1
• Focusing on a single etiology when delirium is often multifactorial 1, 4
• Overlooking medications as a common reversible cause of delirium 3
• Delaying treatment of underlying causes, as delirium should be treated as an acute neurologic emergency 5