Paeds · investigations-procedures-and-technology
Defibrillation, cardioversion and transcutaneous pacing
Also known as Paediatric defibrillation · Synchronised cardioversion · Transcutaneous pacing · External cardiac pacing · Shockable rhythm management
A fellowship approach to delivering an electric shock or an external pacing stimulus to a child's heart, covering the critical distinction between unsynchronised defibrillation for pulseless ventricular fibrillation and pulseless ventricular tachycardia at 4 joules per kilogram, synchronised cardioversion for a perfusing tachyarrhythmia such as supraventricular tachycardia at 1 joule per kilogram escalating to 2 joules per kilogram, and transcutaneous pacing for symptomatic bradycardia from complete heart block. The page teaches the energy doses, the pad positions (anterolateral and anteroposterior), automated external defibrillator use with attenuated paediatric pads in the under-eight-year-old, the sync function that prevents an R-on-T shock, capture thresholds and analgesia for pacing, and the complications of skin burns, myocardial injury and failure to capture. Every dose is anchored to the 2020 American Heart Association Pediatric Advanced Life Support guidance, the 2021 European Resuscitation Council Paediatric Life Support guidelines, and APLS.
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Red flags
- Ventricular fibrillation or pulseless ventricular tachycardia in a child — this is a shockable cardiac arrest rhythm; deliver an unsynchronised shock at 4 joules per kilogram immediately and resume compressions without a pulse check
- Delivering a shock with the synchronisation function left ON for ventricular fibrillation — the defibrillator will not fire because it cannot find an R wave to synchronise to
- A child with supraventricular tachycardia who is shocked in unsynchronised mode — a shock landing on the T wave can precipitate ventricular fibrillation, so always switch SYNC on for a perfusing tachyarrhythmia
- Symptomatic bradycardia with complete heart block that fails to respond to adrenaline — start transcutaneous pacing early rather than escalating inotropes indefinitely
- Using adult defibrillator pads that touch each other on the small chest of an infant — use anteroposterior placement or paediatric pads to avoid arcing between pads
- An infant under one year shocked with an automated external defibrillator using adult energy when a manual defibrillator is available — a manual machine allows the weight-based 4 joules per kilogram dose
Life stages
Care settings
Clinical exam formats
Board mappings
- General and Community Paediatrics
- Recognition and management of the acutely ill child
- Procedural skills — defibrillation and cardioversion
- Emergency and resuscitation medicine
- Current 2026 PREP curriculum — Learning Objective 2.2.1: Recognise, prioritise and manage an acutely ill infant, child or young person including management of shockable cardiac arrest rhythms
- Clinical Applications
- Medical Sciences
- Procedural skills
- Short Cases
- Structured oral — acutely ill or collapsing child
- 1.4 Safely and appropriately performs practical procedures and uses medical devices
- 4. Patient management
- 8. Patient safety
- Foundation of Practice (FOP)
- Applied Knowledge in Practice (AKP)
- Clinical — structured oral and communication in an emergency
- General Pediatrics Content Outline — Emergency Medicine; Procedural skills
- Universal Task 4: Management and Treatment
- Patient Care 1: procedural competency
- Systems-Based Practice
- Medical Expert
- Collaborator
- Pediatrics: Procedural skill — defibrillation and cardioversion
Overview & Definition
Picture a six-year-old in the emergency department with a heart rate of 250, pale and breathless, the monitor showing a narrow-complex tachycardia you cannot break with vagal manoeuvres. Now picture a different child, collapsed and pulseless, the monitor showing a chaotic writhing trace of ventricular fibrillation. Both need an electric shock, but the shocks are different, and confusing them can kill. This topic teaches the three ways electricity is delivered to a child's heart: defibrillation, cardioversion, and transcutaneous pacing. [1] [6]
Defibrillation is the unsynchronised delivery of a direct-current shock across the chest to a heart in ventricular fibrillation or pulseless ventricular tachycardia. The goal is to depolarise the whole myocardium at once, extinguish every re-entry circuit, and hand the sinus node a silent heart it can recapture. Synchronised cardioversion is a timed shock, discharged on the R wave, delivered to a heart that still has a perfusing rhythm — supraventricular tachycardia, atrial flutter, or a stable monomorphic ventricular tachycardia with a pulse — when drug therapy has failed or the child is haemodynamically unstable. Transcutaneous pacing is external electrical stimulation of a bradycardic heart through pads on the chest wall, used as a bridge when intrinsic conduction has failed. [1] [5]
The numbers a fellowship candidate must hold in one line are these: defibrillate ventricular fibrillation and pulseless ventricular tachycardia at 4 joules per kilogram; cardiovert a perfusing tachyarrhythmia at 1 joule per kilogram, escalating to 2 joules per kilogram; and pace a symptomatic bradycardia at a rate of 80 to 100 per minute, increasing the output until you see electrical and mechanical capture. [1] [2]
References12ShowHide
- [1]Topjian AA, Raymond TT, Atkins D, et al Part 4: Pediatric Basic and Advanced Life Support 2020 American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Pediatrics, 2021.PMID 33087552
- [2]Van de Voorde P, Turner NM, Djakow J, et al European Resuscitation Council Guidelines 2021: Paediatric Life Support Resuscitation, 2021.PMID 33773830
- [3]Mercier E, Laroche E, Beck B, et al Defibrillation energy dose during pediatric cardiac arrest: Systematic review of human and animal model studies Resuscitation, 2019.PMID 31029714
- [4]Brugada J, Blom N, Sarquella-Brugada G, et al Pharmacological and non-pharmacological therapy for arrhythmias in the pediatric population: EHRA and AEPC-Arrhythmia Working Group joint consensus statement Europace, 2013.PMID 23851511
- [5]Neubrand TL, Topoz I, Mistry RD Updated Approaches to Cardiac Electrical Stimulation and Pacing in Pediatrics Pediatric Emergency Care, 2020.PMID 32868549
- [6]Samson RA, Atkins DL Tachyarrhythmias and defibrillation Pediatric Clinics of North America, 2008.PMID 18675025
- [7]Lupton JR, Newgard CD, Dennis D, et al Initial Defibrillator Pad Position and Outcomes for Shockable Out-of-Hospital Cardiac Arrest JAMA Network Open, 2024.PMID 39250154
- [8]Atkins DL, Jorgenson DB Attenuated pediatric electrode pads for automated external defibrillator use in children Resuscitation, 2005.PMID 15993727
- [9]Berg RA Attenuated adult biphasic shocks for prolonged pediatric ventricular fibrillation: support for pediatric automated defibrillators Critical Care Medicine, 2004.PMID 15508658
- [10]Atkinson E, Mikysa B, Conway JA, et al Specificity and sensitivity of automated external defibrillator rhythm analysis in infants and children Annals of Emergency Medicine, 2003.PMID 12883506
- [11]Morgan RW, Kirschen MP, Kilbaugh TJ, et al Pediatric In-Hospital Cardiac Arrest and Cardiopulmonary Resuscitation in the United States: A Review JAMA Pediatrics, 2021.PMID 33226408
- [12]Abbasi E, Vijayashankar SS, Goldman RD Management of acute supraventricular tachycardia in children Canadian Family Physician, 2023.PMID 38092445