Pulseless Ventricular Tachycardia Pediatric Dose — Defibrillation
Pulseless ventricular tachycardia (pulseless VT) is a shockable, life-threatening cardiac arrest rhythm in which the ventricles depolarize rapidly without generating a palpable pulse. Immediate unsynchronized defibrillation delivers a high-energy shock to terminate the chaotic electrical activity and restore organized rhythm. It is managed identically to ventricular fibrillation (VF) within the Pediatric Advanced Life Support (PALS) cardiac arrest algorithm.
Pediatric Dosing
- Initial shock: 2 J/kg unsynchronized defibrillation
- Subsequent shocks: 4 J/kg unsynchronized defibrillation
Doses are weight-based. For higher energy requirements in refractory arrest, consult institutional protocol, as the source description does not specify a maximum dose ceiling beyond 4 J/kg.
Worked example — 20 kg child: Initial shock: 20 × 2 J/kg = 40 J. Subsequent shocks: 20 × 4 J/kg = 80 J.
Indications and Clinical Context
Pulseless VT is indicated for unsynchronized defibrillation when a child presents in cardiac arrest with a wide-complex tachycardia and no palpable pulse. Per PALS guidelines, pulseless VT and VF are treated as equivalent shockable rhythms within the cardiac arrest algorithm. Early defibrillation, combined with high-quality CPR, epinephrine, and antiarrhythmic therapy, is the cornerstone of resuscitation for these rhythms.
Defibrillation should not be delayed for vascular access; if IV/IO access is not immediately available, the shock should be delivered first. Rhythm and pulse checks occur after each 2-minute CPR cycle, with repeated shocks delivered if a shockable rhythm persists.
Administration and Monitoring
Pulseless VT requires unsynchronized defibrillation (not synchronized cardioversion). Pediatric-sized pads or paddles should be used for children under approximately 10 kg; adult pads are appropriate for larger children, ensuring pads do not overlap. Confirm correct pad placement (anterior-lateral or anterior-posterior) and minimize hands-off time. Resume CPR immediately after each shock without waiting to reassess rhythm.
- Confirm pulseless status before defibrillation — synchronized cardioversion is used for perfusing tachyarrhythmias
- Ensure all personnel are clear of the patient prior to shock delivery
- Monitor for return of spontaneous circulation (ROSC) after each shock cycle
- Escalate to 4 J/kg for all shocks after the initial 2 J/kg attempt
- Consult institutional protocol for energy dosing beyond 4 J/kg in refractory cases
Disclaimer: This article is an educational reference summarizing standard pediatric dosing values. It is not a substitute for clinical judgment. Always verify doses against institutional protocols, the current edition of authoritative references (e.g., Lexicomp, Harriet Lane Handbook, PALS guidelines), the patient’s accurate weight, and any patient-specific factors (renal/hepatic function, allergies, comedications) before administration.