Delirium

Description

• Delirium is a clinical syndrome characterized by acute changes in awareness, cognition, and perception with a waxing and waning course
• Delirium is often secondary to an underlying acute medical condition
• Pathophysiology unknown:
  • Diffuse cerebral dysfunction
  • Derangements of cerebral acetylcholine
  • CNS dopamine, γ-aminobutyric acid, and serotonin may be involved
• Frequently missed by emergency medicine physicians
• Associated with increased mortality, increased admission, and increased length of stay

Etiology

• Neurologic:
  • Meningitis or encephalitis
  • Seizure
  • Wernicke encephalopathy
  • Hypoxia and hypoperfusion of the brain
  • Intracranial bleed or mass
  • Stroke syndrome
• Pulmonary:
  • Pneumonia
  • Other pulmonary etiology of hypoxia or hypercapnia
• Cardiovascular:
  • Hypertensive crisis
  • Acute coronary syndromes
  • Arrhythmia
• GI:
  • Hepatic encephalopathy
  • Dehydration
• Renal:
  • UTI
  • Acute renal failure
• Endocrine:
  • Hypoglycemia
  • Hyperglycemia
  • Hypothyroid
• Rheumatologic:
  • Collagen vascular disorder
• Toxicologic:
  • Medications or supplements
  • Withdrawal from barbiturates or alcohol
  • Environmental toxins
• Other:
  • Electrolyte abnormalities
  • Vitamin deficiencies
  • Hypothermia
  • Hyperthermia
  • Trauma
  • Surgery

• Common presentation in older ED patients
• Up to 10% of older ED patients may have delirium
• Many patients will present with subtle symptoms and vague chief complaints:
  • Fall, dizzy, or not feeling well
• Waxing and waning symptoms
• Patients with known dementia are prone to develop delirium from acute medical conditions
• Life-threatening condition