What is the initial management of a young person presenting with altered mental status, including the need for a CT (Computed Tomography) scan of the head with CTA (Computed Tomography Angiography)?

Initial Management of Altered Mental Status in a Young Person

In a young person presenting with altered mental status, a non-contrast head CT should be performed as the first-line neuroimaging test, with CT angiography (CTA) added when there is suspicion of vascular pathology, stroke, or hemorrhage. 1

Initial Assessment and Stabilization

1. Airway, Breathing, Circulation (ABC)

   • Ensure patent airway and adequate oxygenation
   • Maintain systolic blood pressure between 130-150 mmHg 1
   • Consider intubation for patients with decreased level of consciousness 2

2. Immediate Bedside Testing

   • Blood glucose (treat if <60 mg/dL) 3
   • Vital signs including temperature, oxygen saturation
   • Electrocardiogram for cardiac causes 4

Neuroimaging Decision-Making

When to Obtain Head CT Without Contrast

• Non-contrast head CT is the first-line neuroimaging test for altered mental status and can be performed safely and rapidly in all patients 1
• Yield of acute findings on CT ranges from 2% to 45% depending on clinical presentation 1
• Risk factors associated with positive findings include:
  • History of trauma or falls
  • Hypertension
  • Anticoagulant use
  • Headache, nausea, or vomiting
  • Impaired consciousness or unresponsiveness
  • Neurologic deficit
  • History of malignancy 1

When to Add CT Angiography (CTA)

• Add CTA when there is suspicion of:
  • Stroke (especially large vessel occlusion)
  • Intracranial hemorrhage requiring vascular assessment
  • Vascular malformation 1
• CTA should be performed immediately following non-contrast CT if ischemic stroke is suspected with disabling deficits 1

MRI Considerations

• MRI may be considered as a second-line test when:
  • Initial CT is unrevealing but clinical suspicion remains high
  • There is suspicion of small infarcts, encephalitis, or subtle subarachnoid hemorrhage 1
  • Patient is stable with suspected central nervous system malignancy, inflammatory disorder, or infection 1

Common Etiologies to Consider

1. Neurological (35%)

   • Stroke (ischemic or hemorrhagic)
   • Seizure (including post-ictal state)
   • Intracranial mass
   • Hydrocephalus 5

2. Toxicological/Pharmacological (23%)

   • Drug intoxication or withdrawal
   • Medication side effects 5
   • Consider naloxone for suspected opioid overdose 3

3. Systemic/Organic (14.5%)

   • Hypoxia
   • Sepsis
   • Organ failure 5

4. Infectious (9.1%)

   • Meningitis/encephalitis
   • Systemic infection with CNS effects 5

5. Metabolic (7.9%)

   • Hypoglycemia/hyperglycemia
   • Electrolyte abnormalities
   • Thyroid disorders 5

Special Considerations for Young Patients

• In young patients, psychiatric causes of altered mental status should be considered only after ruling out organic causes 1
• The diagnostic yield of CT in young patients with new-onset psychosis and no focal neurologic findings is very low (0-1.5%) 1
• Young military recruits with new-onset psychosis showed no clinically significant findings on brain CT scans in one study 1
• Consider substance use, which is common in this age group

Management Algorithm

1. Stabilize (ABCs, treat immediate life threats)
2. Test (glucose, vital signs, ECG)
3. Image (non-contrast head CT ± CTA based on clinical suspicion)
4. Treat specific causes:
   • If intracranial hemorrhage: reverse anticoagulation if applicable, neurosurgical consultation 1
   • If ischemic stroke: consider thrombolysis/thrombectomy if eligible 1
   • If metabolic: correct abnormalities
   • If toxic: specific antidotes as indicated

Pitfalls to Avoid

• Premature attribution to psychiatric causes - Always rule out organic causes first, especially in young patients with new-onset altered mental status
• Delayed neuroimaging - When indicated, neuroimaging should be performed promptly as delays can lead to worse outcomes
• Missing subtle neurological signs - A thorough neurological examination is essential even when initial presentation seems psychiatric
• Overlooking toxicologic causes - Young patients with altered mental status commonly have substance-related etiologies
• Failure to reassess - Continuous monitoring and reassessment is crucial as mental status can rapidly deteriorate

Remember that altered mental status in young people is a serious presentation that requires prompt evaluation and management to prevent morbidity and mortality.