What is the best next step in managing a patient with a history of depression and alcohol use disorder who presents to the ED with slurred speech and drowsiness, smelling of alcohol, and stable vitals?

Head CT is the Best Next Step

In a patient with slurred speech, drowsiness, and alcohol odor who has stable vitals, head CT should be performed emergently to exclude structural intracranial pathology before attributing symptoms solely to intoxication. 1

Why Head CT Takes Priority

Intoxication Does Not Exclude Structural Brain Injury

• Intoxicated patients with altered mental status have significantly impaired sensitivity of clinical decision rules for detecting intracranial injury. The Canadian CT Head Rule demonstrated only 70% sensitivity and NEXUS Head CT showed only 83% sensitivity in intoxicated patients with minor head injury, meaning these tools miss a substantial proportion of clinically important brain injuries when alcohol is involved. 1

• Alcohol intoxication was specifically identified as a higher-risk feature in the New Orleans Criteria for head CT, defined by history, witness account, or examination findings such as speech changes or odor on breath—all present in this patient. 1

• In patients with cirrhosis and altered mental status (relevant given her alcohol use disorder), brain imaging should be considered for first episodes of confusion or when patients present with features different from prior episodes. 1

Depression and Alcohol Use Disorder Increase Risk

• This patient's depression raises concern for intentional self-harm or overdose, which could include head trauma from a fall or assault that she may not recall or report. 1

• Chronic alcohol users are at higher risk for subdural hematomas due to brain atrophy and fragile bridging veins, and these can present with subtle findings that overlap with intoxication. 1

Alternative Diagnoses Must Be Excluded

Hepatic encephalopathy is a diagnosis of exclusion in patients with alcohol use disorder and altered mental status. 1 Other critical causes include:

• Intracranial bleeding (subdural, epidural, subarachnoid hemorrhage)
• Ischemic stroke
• Wernicke's encephalopathy (which can present with altered mental status and slurred speech) 2, 3
• Hypoglycemia
• Electrolyte disorders
• Infections (meningitis, encephalitis)
• Drug toxicity or withdrawal 1

Routine head CT is not warranted in patients with recurrent, nonfocal presentations similar to prior episodes, but this appears to be a first presentation to the ED with these specific symptoms, making imaging appropriate. 1

Why Other Options Are Insufficient as the "Next Step"

Urine Drug Screen (Option A)

• Routine toxicologic screening in alert psychiatric patients with normal vitals and noncontributory exams has only 20% sensitivity for organic etiologies and does not change acute ED management. 1

• While this patient has marijuana cravings, cannabinoids do not cause acute slurred speech and drowsiness requiring ED evaluation. 1

• Drug screening may be useful later for disposition planning but does not take priority over excluding life-threatening structural brain pathology. 1

Liver Function Tests (Option B)

• LFTs provide information about chronic liver disease but do not address the acute presentation of slurred speech and altered mental status. 1

• While important for assessing alcohol-related liver damage, they will not identify the cause of her current neurological symptoms. 1

• These can be obtained after structural brain injury is excluded. 1

TSH (Option C)

• Thyroid dysfunction can cause altered mental status but develops gradually over weeks to months, not acutely. 1

• In patients with psychiatric complaints and normal vital signs, diagnostic evaluation should be directed by history and physical examination, with routine laboratory testing having very low yield. 1

• TSH would be appropriate if there were clinical features suggesting thyroid disease (weight changes, temperature intolerance, skin changes), but acute slurred speech and drowsiness are not typical presentations. 1

Critical Management After Head CT

If CT is Normal

• Administer thiamine 100-500 mg IV immediately before any glucose administration to prevent Wernicke's encephalopathy. 2, 4

• Check fingerstick glucose, complete metabolic panel (including sodium), and magnesium level. 1, 5

• Assess for alcohol withdrawal syndrome, which can begin within 6-24 hours of last drink and includes tremor, tachycardia, hypertension, anxiety, and altered mental status. 6, 2, 5

• Consider benzodiazepines if withdrawal symptoms are present, as they are the gold standard to prevent progression to seizures and delirium tremens. 6, 2

Common Pitfalls to Avoid

• Never attribute altered mental status solely to intoxication without excluding structural brain injury, especially in patients with risk factors for falls or head trauma. 1

• Never administer glucose before thiamine in alcohol-dependent patients, as this can precipitate acute Wernicke's encephalopathy. 2, 4

• Do not assume stable vital signs exclude serious pathology—subdural hematomas and early strokes can present with normal vital signs initially. 1

• The patient's cognitive abilities, rather than a specific blood alcohol level, should guide psychiatric assessment, but structural pathology must be excluded first. 1