title: Dispatcher assistance and automated external defibrillator performance among elders.
abstract: OBJECTIVE
  Automated external defibrillators (AEDs) provide an opportunity to improve survival in out-of-hospital, ventricular fibrillation (VF) cardiac arrest by enabling laypersons not trained in rhythm recognition to deliver lifesaving therapy. The potential role of emergency dispatchers in the layperson use of AEDs is uncertain. This study was performed to examine whether dispatcher telephone assistance affected AED skill performance during a simulated VF cardiac arrest among a cohort of older adults. The hypothesis was that dispatcher assistance would increase the proportion who were able to correctly deliver a shock, but might require additional time.
  
  
  METHODS
  One hundred fifty community-dwelling persons aged 58-84 years were recruited from eight senior centers in King County, Washington. All participants had received AED training approximately six months previously. For this study, the participants were randomized to AED operation with or without dispatcher assistance during a simulated VF cardiac arrest. The proportions who successfully delivered a shock and the time intervals from collapse to shock were compared between the two groups.
  
  
  RESULTS
  The participants who received dispatcher assistance were more likely to correctly deliver a shock with the AED during the simulated VF cardiac arrest (91% vs 68%, p = 0.001). Among those who were able to deliver a shock, the participants who received dispatcher assistance required a longer time interval from collapse to shock [median (25th, 75th percentile) = 193 seconds (165, 225) for dispatcher assistance, and 148 seconds (138, 166) for no dispatcher assistance, p = 0.001].
  
  
  CONCLUSIONS
  Among older laypersons previously trained in AED operation, dispatcher assistance may increase the proportion who can successfully deliver a shock during a VF cardiac arrest.
authors.affiliation: Department of Medicine, University of Washington, Seattle, WA, USA.
authors.forename: R
authors.initials: R
authors.lastname: Ecker
authors.forename: T D
authors.initials: TD
authors.lastname: Rea
authors.forename: H
authors.initials: H
authors.lastname: Meischke
authors.forename: S M
authors.initials: SM
authors.lastname: Schaeffer
authors.forename: P
authors.initials: P
authors.lastname: Kudenchuk
authors.forename: M S
authors.initials: MS
authors.lastname: Eisenberg
mesh_terms: D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D017147:Defibrillators, Implantable / Q000523:psychology; D004554:Electric Countershock / Q000295:instrumentation / Q000523:psychology; D005260:Female; D006323:Heart Arrest / Q000150:complications / Q000523:psychology / Q000628:therapy; D006801:Humans; D008297:Male; D016743:Mental Competency / Q000523:psychology; D008875:Middle Aged; D013997:Time Factors; D014693:Ventricular Fibrillation / Q000150:complications / Q000523:psychology / Q000628:therapy; D014861:Washington / Q000453:epidemiology