In pediatric cardiac arrest, for which rhythm is defibrillation indicated?

• A. Asystole
• B. Pulseless Electrical Activity
• C. Shockable rhythms (VF/VT)
• D. Normal rhythm

Answer: (C)

Defibrillation is used to treat rhythms that are “shockable,” meaning the heart is in a chaotic electrical state that can be reset by a brief electrical shock. In pediatric cardiac arrest, these shockable rhythms are ventricular fibrillation and pulseless ventricular tachycardia. The shock aims to depolarize the heart cells simultaneously so the natural pacemaker can re-establish an organized rhythm and a pulse.

Asystole and pulseless electrical activity, on the other hand, do not have the same chaotic electrical pattern that defibrillation can fix. In asystole there’s no electrical activity to reset, and in PEA there is electrical activity without effective mechanical contraction; delivering a shock won’t restore perfusion in those scenarios, so defibrillation isn’t indicated there. Normal rhythm isn’t a situation requiring defibrillation either.

So the scenario in which defibrillation is indicated is when the rhythm is a shockable one—VF or VT without a pulse. In practice, when this rhythm is identified, deliver the initial shock at the pediatric defibrillation dose (2 J/kg, then 4 J/kg for subsequent shocks) alongside continuing high-quality CPR and appropriate medications per pediatric Advanced Life Support guidelines.