What are the indications and dosages for adrenaline (epinephrine) administration?

Indications and Dosages for Adrenaline (Epinephrine) Administration

Adrenaline (epinephrine) should be administered immediately upon recognition of anaphylaxis or cardiac arrest, with specific dosages based on the clinical indication, patient weight, and severity of presentation. 1

Anaphylaxis Management

Dosing for Anaphylaxis:

• Adults and children ≥30 kg (66 lbs):

  • 0.3-0.5 mg (0.3-0.5 mL of 1:1000 solution) IM or SC
  • Administer into anterolateral aspect of the thigh
  • May repeat every 5-10 minutes as necessary 2

• Children <30 kg (66 lbs):

  • 0.01 mg/kg (0.01 mL/kg of 1:1000 solution), maximum 0.3 mg (0.3 mL)
  • Administer IM or SC into anterolateral aspect of the thigh
  • May repeat every 5-10 minutes as necessary 2

Severity-Based Dosing for Perioperative Anaphylaxis:

• Grade II reaction (moderate hypotension or bronchospasm):

  • Initial dose: 20 μg IV epinephrine
  • If unresponsive after 2 minutes: 50 μg IV epinephrine
  • If IV access unavailable: 300 μg IM epinephrine 3

• Grade III reaction (life-threatening hypotension or bronchospasm):

  • Initial dose: 50 μg IV epinephrine if no other vasopressors/bronchodilators given
  • If unresponsive to other vasopressors/bronchodilators: 100 μg IV epinephrine
  • If unresponsive after 2 minutes: 200 μg IV epinephrine 3

• Grade IV reaction (cardiac or respiratory arrest):

  • Follow advanced life support guidelines: 1 mg IV epinephrine 3

Cardiac Arrest Management

• Adult cardiac arrest:

  • 1 mg IV epinephrine every 3-5 minutes during resuscitation 3, 4
  • Despite studies of high-dose epinephrine, standard dosing remains recommended as no improvement in survival rates has been demonstrated 4, 5

• Refractory management (inadequate response after 10 minutes):

  • Escalate epinephrine dose (doubling the bolus dose)
  • Consider epinephrine infusion (0.05-0.1 μg/kg/min) peripherally
  • Start epinephrine infusion if more than three epinephrine boluses administered 3

Route of Administration

• Intramuscular (IM): Preferred route for anaphylaxis in community settings

  • Mid-outer thigh provides more rapid and reliable absorption 1
  • Most effective and safest route for anaphylaxis outside hospital settings

• Intravenous (IV): For cardiac arrest or severe anaphylaxis in controlled settings

  • Central veins are optimal for rapid delivery into central circulation
  • Peripheral venous cannulation is often quicker, easier, and safer
  • Follow with 10-20 mL 0.9% saline flush 3

• Intraosseous (IO): Alternative when IV access is unavailable in cardiac arrest 6

• Endotracheal: When vascular access is unavailable

  • Use higher doses (2-3 times IV dose)
  • Dilute in 10 mL of sterile water 3

Important Considerations

• Prefilled and appropriately labeled IM-dosed epinephrine syringes should be available to prevent dosing errors 7
• Confusion between anaphylaxis dosing (lower dose, IM) and cardiac arrest dosing (higher dose, IV) can lead to potentially lethal complications 7
• Monitor patients with anaphylaxis for at least 4-6 hours for potential biphasic reactions 1
• Caution should be used before administering epinephrine in patients whose arrest is associated with solvent abuse, cocaine, and other sympathomimetic drugs 3
• Common adverse reactions include anxiety, tremor, dizziness, sweating, palpitations, nausea, headache, and respiratory difficulties 2
• Serious adverse events may include arrhythmias, including fatal ventricular fibrillation, rapid rises in blood pressure causing cerebral hemorrhage, and angina 2

Supportive Care for Anaphylaxis

• Position patients with hypotension supine with legs elevated
• Administer fluid resuscitation immediately
• Provide supplemental oxygen for patients with respiratory symptoms
• Monitor vital signs, including blood pressure, heart rate, and oxygen saturation 1

The evidence clearly supports immediate administration of epinephrine as the cornerstone of treatment for anaphylaxis and cardiac arrest, with appropriate dosing based on the clinical scenario and patient characteristics.