What is the first drug to administer in cardiac arrest?

First Drug to Administer in Cardiac Arrest

In a patient with cardiac arrest, epinephrine (1 mg IV/IO) is the first drug that should be administered every 3-5 minutes regardless of the rhythm. 1, 2

Medication Administration in Cardiac Arrest

Initial Management

• Ensure high-quality CPR is ongoing (100-120 compressions/minute, depth of at least 2 inches/5 cm)
• Check rhythm to determine if shockable (VF/pVT) or non-shockable (asystole/PEA)
• If rhythm is shockable (VF/pVT):
  • Deliver shock immediately
  • Resume CPR for 2 minutes
  • Administer epinephrine 1 mg IV/IO
• If rhythm is non-shockable (asystole):
  • Continue CPR
  • Administer epinephrine 1 mg IV/IO as soon as possible

Epinephrine Administration

• Dose: 1 mg IV/IO every 3-5 minutes 1, 2
• For non-shockable rhythms: Give as soon as feasible after onset of arrest 1
• For shockable rhythms: Administer after the third shock if the patient remains in cardiac arrest 1

Rationale for Epinephrine

Epinephrine works through its alpha-adrenergic effects to increase coronary perfusion pressure and cerebral perfusion pressure during CPR 1. The alpha-adrenergic effects improve cerebral and myocardial blood flow by preventing arterial collapse and increasing peripheral vasoconstriction 3.

Additional Medication Considerations

Amiodarone or Lidocaine

• Only indicated for shock-resistant VF/pVT
• Amiodarone: 300 mg IV/IO bolus, followed by 150 mg if needed 1
• Lidocaine: 1-1.5 mg/kg IV/IO, followed by 0.5-0.75 mg/kg if needed 1

Timing Considerations

While the 2020 AHA guidelines recommend epinephrine as the first drug for cardiac arrest, timing may vary slightly based on the initial rhythm:

• For non-shockable rhythms: Administer as soon as possible 1
• For shockable rhythms: Some evidence suggests administering after the third shock if defibrillation is unsuccessful 1

Common Pitfalls to Avoid

1. Delaying epinephrine administration - For non-shockable rhythms, early administration of epinephrine (within 5 minutes) may increase survival-to-discharge rates 1

2. Excessive focus on airway management - While securing the airway is important, it should not delay or interrupt chest compressions or epinephrine administration

3. Inappropriate dosing - Standard dose of 1 mg is recommended; higher doses have not been shown to improve survival to hospital discharge 4

4. Administering epinephrine too early in shockable rhythms - For VF/pVT, early epinephrine (before adequate defibrillation attempts) may be associated with decreased odds of survival 5

5. Interrupting chest compressions - Medication administration should not cause significant interruptions in chest compressions

The 2020 AHA guidelines provide clear direction that epinephrine is the first-line medication for cardiac arrest, with the timing of administration dependent on the initial rhythm but generally recommended every 3-5 minutes throughout the resuscitation effort 1, 2.