When should an electrocardiogram (EKG) be performed on an intoxicated patient?

EKG Indications for Intoxicated Patients

An EKG should be performed on any intoxicated patient who presents with chest pain, dizziness, syncope, palpitations, or has received an overdose of illicit drugs known to have cardiac effects. 1

Primary Indications for EKG in Intoxicated Patients

• Symptomatic patients:

  • Chest pain or discomfort
  • Dizziness or syncope
  • Palpitations
  • Unexplained dyspnea
  • Extreme fatigue or weakness 1

• Suspected overdose or toxicity:

  • Known or suspected overdose of alcohol or drugs with cardiac effects
  • Concomitant use of alcohol with other substances (especially cocaine) 1
  • History of binge drinking or chronic alcoholism 2

• Abnormal vital signs:

  • Significant tachycardia or bradycardia
  • Hypertension or hypotension
  • Irregular pulse

Evidence-Based Rationale

Alcohol intoxication can cause several significant ECG changes that may indicate increased risk for arrhythmias:

1. Interval prolongation: High blood alcohol concentrations are associated with prolongation of P wave, PR, QRS, and QTc intervals 3

2. Arrhythmia risk: Intoxicated patients may develop:

   • Atrial fibrillation (most common tachyarrhythmia)
   • Ventricular arrhythmias including torsades de pointes
   • Sinus bradycardia (which may cause syncope) 2

3. Holiday Heart Syndrome: Even in otherwise healthy individuals, alcohol can trigger arrhythmias 2

4. Silent myocardial ischemia: Alcohol intoxication can worsen ischemia in patients with underlying coronary disease, often without symptoms 2

Special Considerations

Cocaine and Alcohol

When alcohol is combined with cocaine use, the risk of cardiac complications increases significantly. Patients with cocaine and alcohol co-ingestion should receive an ECG regardless of symptoms due to:

• Increased risk of coronary vasospasm
• Potential for myocardial ischemia even hours after use
• Formation of cocaethylene (more cardiotoxic than cocaine alone) 1

Withdrawal States

Patients in alcohol withdrawal also warrant ECG monitoring as:

• ECG changes similar to acute intoxication can occur during withdrawal
• Risk of stress-induced cardiomyopathy during withdrawal 4
• Delirium tremens carries particularly high cardiovascular risk 2

Management Algorithm

1. For all intoxicated patients:

   • Obtain baseline vital signs
   • Assess for cardiac symptoms (even if minimized by patient)
   • Consider EKG if any cardiac symptoms are present

2. Mandatory EKG indications:

   • Any cardiac symptoms (chest pain, palpitations, syncope)
   • Known or suspected overdose
   • Abnormal vital signs
   • History of cardiovascular disease
   • Co-ingestion with other substances (especially stimulants)
   • Signs of alcohol withdrawal

3. Interpretation considerations:

   • Look specifically for prolonged intervals (P wave, PR, QRS, QTc)
   • Assess for arrhythmias (especially atrial fibrillation)
   • Compare with previous ECGs when available
   • Do not rely solely on automated measurements 5

4. Follow-up:

   • Consider repeat ECG after sobriety if initial ECG showed abnormalities
   • For patients with significant arrhythmias, monitor until resolution

Common Pitfalls

• Dismissing symptoms as solely due to intoxication - cardiac symptoms may be attributed to anxiety or intoxication when they represent true cardiac pathology
• Missing electrolyte disturbances - alcohol can cause electrolyte abnormalities that further increase arrhythmia risk
• Overlooking withdrawal risk - patients may develop cardiac complications during withdrawal, not just during acute intoxication
• Relying on patient history alone - intoxicated patients may minimize or be unaware of cardiac symptoms

Remember that the American College of Cardiology/American Heart Association guidelines specifically state that physician judgment may transcend specific recommendations, and there may be instances when it is appropriate to obtain an ECG even when no cardiac symptom is present 1.