What is the plan of care for a patient presenting with altered mental status?

Management of Altered Mental Status

The management of altered mental status requires immediate airway assessment, rapid identification of underlying causes, and concurrent empiric treatment, with neuroimaging reserved for specific clinical scenarios.

Initial Assessment and Stabilization

• Airway protection is the first priority in patients with altered mental status to prevent aspiration, with transfer to a monitored setting if necessary 1, 2
• Assess mental status severity using validated scales such as the Glasgow Coma Scale or West Haven criteria to objectively quantify impairment 1, 3
• Decisions regarding intubation should be based on: inability to maintain airway, massive upper GI bleeding, or respiratory distress 1
• For sedation in intubated patients, short-acting medications such as propofol or dexmedetomidine are preferred over benzodiazepines 1

Diagnostic Evaluation

• Investigation of altered mental status should occur concurrently with initial stabilization and empiric treatment 1, 3
• Obtain comprehensive metabolic laboratory assessment including complete blood count, comprehensive metabolic panel, electrolytes, renal and liver function tests 3, 4
• Toxicology screens should be performed when substance use is suspected 3, 5
• Head CT without contrast is usually appropriate as first-line neuroimaging for patients with:
  • First episode of altered mental status
  • Focal neurological deficits
  • Seizures
  • Increased risk for intracranial bleeding (anticoagulant use, coagulopathy)
  • Hypertensive emergency
  • Clinical suspicion for intracranial infection, mass, or elevated intracranial pressure 1, 3
• Brain MRI may be appropriate when CT is negative but clinical suspicion for intracranial pathology remains high 3

Common Etiologies to Consider

• Neurological causes (30-35%): intracranial mass, stroke, encephalitis, meningitis 3, 6
• Toxicologic/Pharmacologic causes (20-25%): medication side effects, alcohol intoxication, illicit drug use 3, 5
• Metabolic/Systemic causes (15-20%): hypoglycemia, electrolyte abnormalities, hepatic encephalopathy, uremia 3, 6
• Infectious causes (9-18%): sepsis, urinary tract infection, pneumonia, meningitis 3, 6

Management Principles

• Treat underlying causes while providing supportive care 4
• For hepatic encephalopathy, follow these principles:
  • Identify and treat precipitating factors 1
  • Initiate empiric therapy with lactulose 1
  • Consider rifaximin for patients not responding to lactulose alone 1
  • Avoid sedating medications such as benzodiazepines and opioids when possible 1
• For suspected intracranial infection, early empiric antimicrobial therapy should be initiated while awaiting diagnostic results 1, 3
• For toxicologic causes, specific antidotes should be administered when available 3, 5
• For metabolic derangements, correct electrolyte abnormalities, glucose levels, and acid-base disturbances 3, 4

Special Considerations

• In patients with cirrhosis, hepatic encephalopathy is a common cause of altered mental status but remains a diagnosis of exclusion 1
• Routine ammonia level testing is not recommended in patients with cirrhosis and altered mental status, as a normal value calls for diagnostic reevaluation 1
• In elderly patients, delirium is often multifactorial and carries higher mortality (10.8% vs 6.9% in younger patients) 3, 5
• For patients with known intracranial pathology and worsening mental status, neuroimaging should be performed to assess for progression 3

Pitfalls to Avoid

• Attributing altered mental status solely to psychiatric causes without adequate medical workup 3, 4
• Failing to consider multiple concurrent etiologies, especially in elderly patients 3, 6
• Relying on ammonia levels alone to diagnose hepatic encephalopathy in cirrhotic patients 1
• Delaying empiric treatment while awaiting diagnostic results in potentially life-threatening conditions 3, 4
• Using physical restraints, which should be avoided or used only for the shortest time possible when no alternatives exist 4