Authors' objectives:

The Ontario Health Technology Advisory Committee asked the Medical Advisory Secretariat to prepare this report on the effectiveness and cost-effectiveness of the use of automated external defibrillators (AEDs). Specifically, the objectives were to identify the components of a program to deliver early defibrillation that optimize the effectiveness of AEDs in out-of-hospital and hospital settings, to determine whether AEDs are cost-effective, and if cost-effectiveness was determined, to advise on how they should be distributed in Ontario.

Authors' results and conclusions: A total of 133 articles were identified; 62 were excluded after reviewing titles and abstracts. Of the 71 articles reviewed, 8 reported findings of 2 large studies, the Ontario Prehospital Advanced Life Support (OPALS) study and the Public Access Defibrillation (PAD) trial. These studies examined the effect of a community program to respond to cardiac arrest with and without the use of AEDs. Their authors had reported a significant reduction in overall mortality from cardiac arrest with the use of AEDs. Factors That Improve the Effectiveness of an AED Program The PAD trial investigators reported a significant improvement in survival (P = .03) after providing AEDs in public access areas and training volunteers in cardiopulmonary resuscitation (CPR) compared with training volunteers in CPR only. The OPALS study investigators reported odds ratios (ORs) and 95% confidence intervals (CIs) for significant predictors of survival, which were age (OR [age per 10 year], 0.8; CI, 0.8-0.9), arrest witnessed by bystander (OR, 3.9; CI, 2.7-5.5), CPR initiated by bystander (OR, 3.7; CI, 2.6-5.1), CPR initiated by first responder (OR, 1.6; CI, 1.1-2.3), and emergency medical service response within 8 minutes (OR, 3.0; CI, 1.8-5.1). The last 3 variables are modifiable and thus may improve the effectiveness of an AED program. For example, the rate of bystander-initiated CPR was only 14% in the OPALS study, but it was 100% in the PAD trial. This was because PAD trial investigators trained community volunteers whereas the OPALS study investigators did not.

Authors' recommendations: The OPALS study model appears cost-effective, and effectiveness can be further enhanced by training community volunteers to improve the bystander-initiated CPR rates. Deployment of AEDs in all public access areas and in houses and apartments is not cost-effective. Further research is needed to examine the benefit of in-home use of AEDs in patients at high risk of cardiac arrest.

Authors' methods: Systematic review

Project Status: Completed

URL for project: http://www.health.gov.on.ca/english/providers/program/mas/tech/techlist_ mn.html

Year Published: 2005

English language abstract: An English language summary is available

Publication Type: Not Assigned

Country: Canada

Organisation Name: Medical Advisory Secretariat

Contact Address: Medical Advisory Secretariat, 20 Dundas Street West, 10th Floor, Toronto, ON M5G 2N6 CANADA. Tel: 416-314-1092l; Fax: 416-325-2364;

Contact Name: MASinfo.moh@ontario.ca

Contact Email: MASinfo.moh@ontario.ca

Copyright: Medical Advisory Secretariat, Ontario Ministry of Health and Long-Term Care