In pediatric unstable WPW, what is the initial DC energy dose for synchronized cardioversion?

• A. 1 J/kg
• B. 0.5 J/kg
• C. 2 J/kg
• D. 4 J/kg

Answer: (A)

In unstable pediatric WPW, the first step is synchronized cardioversion to restore perfusion. The starting energy for this shock is 1 J/kg, chosen to provide effective conversion while keeping safety in small children. If the rhythm persists, you follow up with higher energy doses: 2 J/kg for the next shock, and then 4 J/kg if needed. Delivering the shock with synchronization is crucial to avoid shocking on the T wave, which can trigger dangerous rhythms. While 0.5 J/kg is within some pediatric protocols for other tachyarrhythmias, the standard initial dose for unstable tachycardia requiring synchronized cardioversion is 1 J/kg.