Automatic external defibrillators: changing the way we manage ventricular fibrillation.
OBJECTIVE
To discuss recent developments in automatic defibrillation and to review the evidence that first-responders equipped with automatic external defibrillators (AEDs) improve survival from out-of-hospital cardiac arrest.


METHODS
MEDLINE search from 1966 to 1999 (articles in English only) and examination of bibliographies.


METHODS
Published studies of out-of-hospital cardiac arrest and first-responders equipped with AEDs. Studies had to have a control group and to report survival to hospital discharge from ventricular fibrillation (VF).


METHODS
Six studies met the selection criteria (two prospective randomised trials, two prospective controlled trials, and one cohort study and one retrospective study, both with historical controls).


RESULTS
A random effects meta-analysis of odds ratios for survival from VF.


CONCLUSIONS
Meta-analysis suggests that equipping first-responders with AEDs increases the probability of survival to hospital discharge after out-of-hospital cardiac arrest (odds ratio, 1.74; 95% CI, 1.27-2.38; P < 0.001). However, most of the studies lacked sufficient power to draw definitive conclusions. Until the impact of wide deployment of AEDs is fully understood, first-responder defibrillation in Australia should only occur as part of coordinated multicentre research studies.
Smith
K L
KL
Department of Epidemiology and Preventive Medicine, Monash Medical School, Alfred Hospital, Melbourne, VIC. karen.smith@med.monash.edu.au
Cameron
P A
PA
Peeters
A
A
Meyer
A D
AD
McNeil
J J
JJ
D001315:Australia / Q000453:epidemiology; D001331:Automation / Q000295:instrumentation; D004554:Electric Countershock / Q000295:instrumentation*; D004632:Emergency Medical Services; D004638:Emergency Treatment / Q000295:instrumentation*; D006323:Heart Arrest / Q000401:mortality / Q000628:therapy*; D006801:Humans; D016017:Odds Ratio; D016019:Survival Analysis; D016896:Treatment Outcome