Clinical Research
Heart Rhythm Disorders
Survival After Application of Automatic External Defibrillators Before Arrival of the Emergency Medical System: Evaluation in the Resuscitation Outcomes Consortium Population of 21 Million

https://doi.org/10.1016/j.jacc.2009.11.077Get rights and content
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Objectives

The purpose of this study was to assess the effectiveness of contemporary automatic external defibrillator (AED) use.

Background

In the PAD (Public Access Defibrillation) trial, survival was doubled by focused training of lay volunteers to use an AED in high-risk public settings.

Methods

We performed a population-based cohort study of persons with nontraumatic out-of-hospital cardiac arrest before emergency medical system (EMS) arrival at Resuscitation Outcomes Consortium (ROC) sites between December 2005 and May 2007. Multiple logistic regression was used to assess the independent association between AED application and survival to hospital discharge.

Results

Of 13,769 out-of-hospital cardiac arrests, 4,403 (32.0%) received bystander cardiopulmonary resuscitation but had no AED applied before EMS arrival, and 289 (2.1%) had an AED applied before EMS arrival. The AED was applied by health care workers (32%), lay volunteers (35%), police (26%), or unknown (7%). Overall survival to hospital discharge was 7%. Survival was 9% (382 of 4,403) with bystander cardiopulmonary resuscitation but no AED, 24% (69 of 289) with AED application, and 38% (64 of 170) with AED shock delivered. In multivariable analyses adjusting for: 1) age and sex; 2) bystander cardiopulmonary resuscitation performed; 3) location of arrest (public or private); 4) EMS response interval; 5) arrest witnessed; 6) initial shockable or not shockable rhythm; and 7) study site, AED application was associated with greater likelihood of survival (odds ratio: 1.75; 95% confidence interval: 1.23 to 2.50; p < 0.002). Extrapolating this greater survival from the ROC EMS population base (21 million) to the population of the U.S. and Canada (330 million), AED application by bystanders seems to save 474 lives/year.

Conclusions

Application of an AED in communities is associated with nearly a doubling of survival after out-of-hospital cardiac arrest. These results reinforce the importance of strategically expanding community-based AED programs.

Key Words

automatic external defibrillator
cardiac arrest
cardiopulmonary resuscitation
defibrillation
resuscitation

Abbreviations and Acronyms

AED
automatic external defibrillator
CPR
cardiopulmonary resuscitation
EMS
emergency medical services
OHCA
out-of-hospital cardiac arrest
OR
odds ratio
VF
ventricular fibrillation
VT
ventricular tachycardia

Cited by (0)

The Resuscitation Outcomes Consortium (ROC) is supported by a series of cooperative agreements to 10 regional clinical centers and 1 data coordinating center (5U01 HL077863, HL077881, HL077871HL077872, HL077866, HL077908, HL077867, HL077885, HL077887, HL077873, and HL077865) from the National Heart, Lung and Blood Institutein partnership with the National Institute of Neurological Disorders and Stroke; the U.S. Army Medical Research & Material Command; The Canadian Institutes of Health Research (CIHR)–Institute of Circulatory and Respiratory Health; Defence Research and Development Canada; the American Heart Association; and the Heart and Stroke Foundation of Canada. Some ROC site emergency medical systems have received equipment or concessions from automatic external defibrillator manufacturers. The ROC coordinating center accepts support for receptions from corporations. Dr. Weisfeldt receives salary support from NIH via the ROC. Dr. Ornato is an unpaid Science Advisory Board member of Zoll. Dr. Rea received research support from Medtronic, Inc., and Philips, Inc.Dr. Aufderheide is a consultant for Medtronics, Inc., and JoLife, Inc. Dr. Nichol is a co-principal investigator of the ROC Data Coordinating Center (NHLBI); principal investigator of the randomized trial of hemofiltration after resuscitation from cardiac arrest (NHLBI); co-investigator of the randomized field trial of cold saline IV after resuscitation after cardiac arrest (NHLBI); principal investigator of the randomized trial of CPR training aid in community (Asmund S. Laerdal Foundation for Acute Medicine); has received travel expenses from Innercool Therapies Inc., Radiant Medical Inc., and the American Heart Association; and is a consultant for Triage Wireless.