Year: 2010
Type: article
Abstract: OverviewThis chapter presents guidelines for defibrillation with manual defibrillators and automated external defibrillators (AEDs), synchronized cardioversion, and pacing.AEDs may be used by lay rescuers and healthcare providers as part of basic life support.Manual defibrillation, cardioversion, and pacing are advanced life support therapies. Defibrillation Plus CPR: A Critical CombinationEarly defibrillation is critical to survival from sudden cardiac arrest (SCA) for several reasons 1 : the most frequent initial rhythm in out-of-hospital witnessed SCA is ventricular fibrillation (VF), 2 the treatment for ventricular fibrillation is defibrillation, 3 the probability of successful defibrillation diminishes rapidly over time, 4 and VF tends to deteriorate to asystole over time.1,5,6 Several studies have documented the effects of time to defibrillation and the effects of bystander CPR on survival from SCA.For every minute that passes between collapse and defibrillation, survival rates from witnessed VF SCA decrease 7% to 10% if no CPR is provided.1 When bystander CPR is provided, the decrease in survival rates is more gradual and averages 3% to 4% per minute from collapse to defibrillation.1,2,5,7 CPR can double 1,3 or triple 4 survival from witnessed SCA at most intervals to defibrillation.If bystanders provide immediate CPR, many adults in VF can survive with intact neurologic function, especially if defibrillation is performed within 5 to 10 minutes after SCA.8,9 CPR prolongs VF, delays the onset of asystole, 10 -12 and extends the window of time during which defibrillation can occur.Basic CPR alone, however, is unlikely to terminate VF and restore a perfusing rhythm. New Recommendations to Integrate CPR and AED UseTo treat VF SCA, rescuers must be able to rapidly integrate CPR with use of the AED.To give the victim the best chance of survival, 3 actions must occur within the first moments of a cardiac arrest 1 : activation of the emergency medical services (EMS) system, 2 provision of CPR, and operation of an AED. 3 When 2 or more rescuers are present, activation of EMS and initiation of CPR can occur simultaneously.Delays to either the start of CPR or the start of defibrillation reduce survival from SCA.In the 1990s, some predicted that CPR could be rendered obsolete by the widespread development of community AED programs.However, Cobb 9 noted that as more of Seattle's first responders were equipped with AEDs, survival rates from SCA unexpectedly fell.This decline was attributed to reduced emphasis on CPR, and there is growing evidence to support this view.Part 5: "Adult Basic Life Support" summarizes the evidence on the importance of provision of high-quality CPR (including chest compressions of adequate rate and depth, allowing full chest recoil after each compression and minimizing interruptions in compressions).Two critical questions about integration of CPR with defibrillation were evaluated during the 2010 International Consensus Conference on CPR and Emergency Cardiovascular Care.13 The first question concerned whether CPR should be provided before defibrillation is attempted.The second question concerned the number of shocks to be delivered in a sequence before the rescuer resumes CPR. Shock First Versus CPR FirstWhen any rescuer witnesses an out-of-hospital arrest and an AED is immediately available on-site, the rescuer should start CPR and use the AED as soon as possible.Healthcare providers who treat cardiac arrest in hospitals and other facilities with AEDs on-site should provide immediate CPR and should use the AED/defibrillator as soon as it is available.These recommendations are designed to support early CPR and early defibrillation, particularly when an AED is available within moments of the onset of SCA.In studies in which EMS call-to-arrival intervals were 4 9 to 5 8 minutes or longer, 1 1 ⁄2 to 3 minutes of CPR before defibrillation increased the rate of initial resuscitation (return of spontaneous circulation or ROSC), survival to hospital discharge, 8,9 and 1-year survival 8 when compared with immediate defibrillation
Source: Circulation
Language: English
Subfield: Emergency Medicine
Field: Medicine
Domain: Health Sciences
Open Access status: bronze
OpenAlex ID: W1970448437