title: Increasing first responder CPR during resuscitation of out-of-hospital cardiac arrest using automated external defibrillators.
abstract: OBJECTIVE
  Evidence supports that increasing the balance of "hands-on" CPR may improve survival in ventricular fibrillation out-of-hospital cardiac arrest (OHCA). We assessed whether training and/or AED reconfiguration was associated with an increase in the proportion of time during which CPR was performed between first and second stacks of shocks.
  
  
  METHODS
  The investigation was a cohort study of 291 persons who suffered ventricular fibrillation OHCA and were treated with at least two stacks of AED shocks by emergency medical services (EMS) first-tier responders. In January 2003, first-tier providers were retrained regarding the importance of CPR. In addition, a subset of AEDs was reconfigured to remove continuous fibrillation detection and its associated voice prompts as to be comparable with other AED models. The amount of time spent on CPR was assessed through review of AED electronic and audio recordings to compare the pre-intervention (n = 241) and post-intervention periods (n = 50).
  
  
  RESULTS
  The proportion of time spent performing hands-on CPR between first and second stacks of shocks was 0.40 in the pre-intervention period compared to 0.51 in the post-intervention period (p = 0.001). The difference was greatest for AEDs where EMS was retrained and the AED reconfigured (0.33 versus 0.50, p = 0.01). No difference in survival was detected between the pre- and post-intervention periods (24.9% versus 28.0%, p = 0.65).
  
  
  CONCLUSIONS
  An intervention consisting of retraining and AED reconfiguration was associated with an increase in the proportion of time spent performing CPR between first and second stacks of shocks by first-tier EMS. Whether this increase improves patient outcomes requires additional study.
authors.affiliation: Department of Emergency Medicine, Brigham and Women's Hospital and Mass General, Harvard University, Neville House, Boston (SS), MA 02115, USA. SSHAH11@PARTNERS.ORG
authors.forename: Sachita
authors.initials: S
authors.lastname: Shah
authors.forename: Michele
authors.initials: M
authors.lastname: Garcia
authors.forename: Thomas D
authors.initials: TD
authors.lastname: Rea
mesh_terms: D000368:Aged; D016887:Cardiopulmonary Resuscitation; D015331:Cohort Studies; D047548:Defibrillators; D004632:Emergency Medical Services; D005260:Female; D006323:Heart Arrest / Q000628:therapy*; D006801:Humans; D008297:Male; D012151:Resuscitation / Q000295:instrumentation*; D016896:Treatment Outcome; D014693:Ventricular Fibrillation / Q000628:therapy