During CPR, when an AED monitor shows sinus bradycardia, which drug is appropriate to administer?

During CPR, when an AED monitor shows sinus bradycardia, which drug is appropriate to administer?

• A. Epinephrine
• B. Amiodarone
• C. Atropine
• D. Lidocaine

Answer: (C)

When the rhythm is sinus bradycardia with poor perfusion during CPR, the first-line drug is atropine. It works by blocking vagal influences on the heart, which increases SA node automaticity and improves AV conduction, helping to raise the heart rate and restore better perfusion during resuscitation. The usual dose is 0.5 mg IV every 3–5 minutes, up to a total of 3 mg. If bradycardia persists after atropine, escalation is appropriate, such as pacing or infusions of drugs like epinephrine or dopamine. Epinephrine is more central to cardiac arrest rhythms (like asystole or PEA) and is not the preferred first choice for isolated bradycardia. Amiodarone and lidocaine are antiarrhythmics used for tachyarrhythmias (e.g., VT/VF) and are not indicated for sinus bradycardia; they wouldn’t address the slowed rhythm and can worsen it.

When the rhythm is sinus bradycardia with poor perfusion during CPR, the first-line drug is atropine. It works by blocking vagal influences on the heart, which increases SA node automaticity and improves AV conduction, helping to raise the heart rate and restore better perfusion during resuscitation. The usual dose is 0.5 mg IV every 3–5 minutes, up to a total of 3 mg.

If bradycardia persists after atropine, escalation is appropriate, such as pacing or infusions of drugs like epinephrine or dopamine. Epinephrine is more central to cardiac arrest rhythms (like asystole or PEA) and is not the preferred first choice for isolated bradycardia. Amiodarone and lidocaine are antiarrhythmics used for tachyarrhythmias (e.g., VT/VF) and are not indicated for sinus bradycardia; they wouldn’t address the slowed rhythm and can worsen it.