Show Summary Details
Page of

Defibrillation and pacing during cardiac arrest 

Defibrillation and pacing during cardiac arrest
Defibrillation and pacing during cardiac arrest

Charles D. Deakin

Page of

PRINTED FROM OXFORD MEDICINE ONLINE ( © Oxford University Press, 2022. All Rights Reserved. Under the terms of the licence agreement, an individual user may print out a PDF of a single chapter of a title in Oxford Medicine Online for personal use (for details see Privacy Policy and Legal Notice).

date: 25 June 2022

Defibrillation is the passage of electrical current across the myocardium to allow synchronized repolarisation and return of a perfusing rhythm. It is now an established intervention for patients in shockable rhythms during cardiac arrest and is administered every 2 minutes during resuscitation until return of spontaneous circulation. Modern biphasic waveforms are more effective than older monophasic waveforms, achieving first shock success rate of approximately 90%. For ventricular fibrillation in adults, the initial shock should be delivered at 150 J, and if further shocks are required, escalating energy is probably more effective than a fixed energy strategy. All paediatric shocks should be delivered at 4 J/kg. Although it is important to stand clear of the patient when the shock is delivered, defibrillation should be administered with minimal interruption to resuscitation, ideally resulting in a pause to chest compressions of no more than 5 seconds. External pacing may be life-saving in patients refractory to pharmacological support of bradyarrhythmias, but is ineffective for asystole.

Access to the complete content on Oxford Medicine Online requires a subscription or purchase. Public users are able to search the site and view the abstracts for each book and chapter without a subscription.

Please subscribe or login to access full text content.

If you have purchased a print title that contains an access token, please see the token for information about how to register your code.

For questions on access or troubleshooting, please check our FAQs, and if you can't find the answer there, please contact us.