Public access defibrillation in out-of-hospital cardiac arrest: a community-based study.

BACKGROUND: The dissemination and use of automated external defibrillators (AEDs) beyond traditional emergency medical services (EMS) into the community has not been fully evaluated. We evaluated the frequency and outcome of non-EMS AED use in a community experience. METHODS AND RESULTS: The investigation was a cohort study of out-of-hospital cardiac arrest cases due to underlying heart disease treated by public access defibrillation (PAD) between January 1, 1999, and December 31, 2002, in Seattle and surrounding King County, Washington. Public access defibrillation was defined as out-of-hospital cardiac arrest treated with AED application by persons outside traditional emergency medical services. The EMS of Seattle and King County developed a voluntary Community Responder AED Program and registry of PAD AEDs. During the 4 years, 475 AEDs were placed in a variety of settings, and more than 4000 persons were trained in cardiopulmonary resuscitation and AED operation. A total of 50 cases of out-of-hospital cardiac arrest were treated by PAD before EMS arrival, which represented 1.33% (50/3754) of all EMS-treated cardiac arrests. The proportion treated by PAD AED increased each year, from 0.82% in 1999 to 1.12% in 2000, 1.41% in 2001, and 2.05% in 2002 (P=0.019, test for trend). Half of the 50 persons treated with PAD survived to hospital discharge, with similar survival for nonmedical settings (45% [14/31]) and out-of-hospital medical settings (58% [11/19]). CONCLUSIONS: PAD was involved in only a small but increasing proportion of out-of-hospital cardiac arrests.

Factors impeding dispatcher-assisted telephone cardiopulmonary resuscitation.

STUDY OBJECTIVE: Dispatcher-assisted telephone cardiopulmonary resuscitation (CPR) instruction can increase the proportion of sudden cardiac arrest victims who receive bystander CPR and has been associated with improved survival. Most sudden cardiac arrest victims, however, do not receive bystander CPR. The study objective was to examine factors that may impede implementation of telephone CPR. METHODS: We reviewed dispatcher audio recordings and emergency medical services reports for 404 cases of sudden cardiac arrest that occurred from July 1, 2000, to June 30, 2002, in the study county to assess the phase (1, instructions not offered; 2, instructions offered but declined; or 3, instructions offered and accepted but CPR not implemented) and specific factors within each phase that potentially impede telephone CPR. RESULTS: Twenty-five percent (99/404) of victims received bystander CPR without dispatch assistance, 34% (139/404) received telephone CPR, and 41% (166/404) did not receive bystander CPR. Each phase of telephone CPR process impeded the implementation of CPR: (1) instructions not offered in 48% (80/166); (2) instructions offered but declined in 31% (52/166); and (3) instructions offered and accepted but CPR not implemented in 21% (34/166). During the first phase, telephone CPR was potentially impeded most frequently because the victim was reported to have signs of life (51/80, 64%); during the second and third phases, telephone CPR was most often impeded because of bystander physical limitation (32/86, 37%). Emotional distress, disease transmission, disagreeable victim characteristics, or medicolegal concerns uncommonly impeded telephone CPR (10/86, 12%). CONCLUSION: Factors potentially impeding telephone CPR can be identified. Although many are logistically challenging, some may be addressable and hence provide opportunities to strengthen the chain of survival.