Can intramuscular (IM) epinephrine be administered in a code situation when no intravenous (IV) access can be established?

Intramuscular Epinephrine in Code Situations When IV Access Cannot Be Established

When intravenous access cannot be established during a code situation, intramuscular (IM) epinephrine can be administered as an alternative route while continuing efforts to obtain IV or intraosseous (IO) access.

Route Prioritization in Cardiac Arrest

1. First-line routes:

   • Intravenous (IV) access
   • Intraosseous (IO) access

2. Alternative routes when IV/IO unavailable:

   • Endotracheal (ET) administration (higher doses required)
   • Intramuscular (IM) administration

Evidence-Based Recommendations

Pediatric Patients

• The 2020 American Heart Association guidelines for pediatric life support state that if no IV or IO access is available, epinephrine may be given via the endotracheal route at a dose of 0.1 mg/kg 1.
• Recent research (2024) in a pediatric porcine model found that IM epinephrine resulted in similar resuscitation outcomes to IV epinephrine in both bradycardic and asystolic cardiac arrest 2.

Neonatal Patients

• For neonatal resuscitation, if adequate ventilation and chest compressions have failed to increase heart rate to 60 beats per minute and IV access is not available, endotracheal epinephrine administration is reasonable 1.
• When using the endotracheal route in neonates, a larger dose (0.05-0.1 mg/kg) will likely be required to achieve an effect similar to the 0.01 mg/kg IV dose 1.

Dosing Considerations

• IV/IO dosing: 0.01 mg/kg (0.1 mL/kg of 1:10,000 concentration)
• ET dosing: 0.05-0.1 mg/kg (0.5-1 mL/kg of 1:10,000 concentration)
• IM dosing (based on anaphylaxis protocols):
  • Adults: 0.3-0.5 mg (0.3-0.5 mL of 1:1,000 concentration)
  • Children: 0.01 mg/kg up to 0.3 mg maximum 3

Important Clinical Considerations

Anatomical Site for IM Administration

• Administer IM epinephrine into the anterolateral aspect of the thigh for optimal absorption 3.
• Avoid injection into buttocks, digits, hands, or feet as this may lead to poor absorption or tissue damage 3.

Limitations and Caveats

• IM administration may have delayed onset compared to IV/IO routes due to compromised peripheral perfusion during cardiac arrest.
• Continue efforts to establish IV or IO access while using alternative routes.
• The 2015 AHA guidelines emphasize that IV administration is preferred as soon as venous access is established 1.

Emerging Evidence

• While traditional guidelines prioritize IV/IO/ET routes, recent research suggests IM epinephrine could be considered when immediate administration is needed and other routes are unavailable 2.
• This approach may be particularly relevant in settings with limited resources or personnel trained in IV/IO access.

Algorithm for Epinephrine Administration in Code Situations

1. Attempt IV/IO access immediately
2. If IV/IO access unsuccessful after 2 minutes:
   • Option A: Continue attempts at IV/IO access while administering ET epinephrine (if airway established)
   • Option B: Administer IM epinephrine into anterolateral thigh while continuing attempts at IV/IO access
3. Once IV/IO access established:
   • Switch to standard IV/IO epinephrine administration protocol
   • Continue CPR and reassess every 2 minutes

Remember that establishing definitive IV or IO access remains the priority, but IM epinephrine may serve as a bridge until preferred routes are available.