title: Evaluating the quality of prehospital cardiopulmonary resuscitation by reviewing automated external defibrillator records and survival for out-of-hospital witnessed arrests.
abstract: OBJECTIVE
  Without an easy method to monitor the performance of prehospital cardiopulmonary resuscitation (CPR), earlier studies have not been able to assess the quality of CPR. In this study, we have used a new approach to evaluate prehospital CPR performance and the impact on outcome using data retrieved from the automatic external defibrillators (AED).
  
  
  METHODS
  Electrocardiography (ECG) and voice records from AED data cards from 633 out-of-hospital cardiac arrests (OHCA) were reviewed. Fifty-two witnessed cardiac arrests in ventricular fibrillation (VF) requiring post-shock CPR underwent an independent, structured review by two physicians. The adequacy of prehospital CPR was defined on the basis of noticeable deflection of the ECG with chest compressions, the actual number of chest compressions delivered per minute, and the continuity of prehospital CPR at the scene and during transport. Outcome measures included return of spontaneous circulation (ROSC) and survival to hospital admission and discharge.
  
  
  RESULTS
  The quality of prehospital CPR was judged as adequate in 15 (29%, 95%; CI: 18-42%) and inadequate in 37 (71%, 95%; CI: 58-82%) of the consensus. Adequate CPR performance resulted in a higher rate of ROSC at the scene (53% versus 8%, 95% CI of the difference 14-76%), and survival to hospital discharge (53% versus 8%, 95% CI of the difference 14-76%). Two reviewers agreed on whether CPR was adequate in 92.3% of cases, with a kappa of 0.82.
  
  
  CONCLUSIONS
  The quality of prehospital CPR is associated with a greater likelihood of survival in witnessed VF arrests in need of post-shock CPR. The potential of widely available electrocardiography and voice records in AEDs in providing a convenient and real-time evaluation of prehospital CPR should be explored further.
authors.affiliation: Department of Emergency Medicine, National Taiwan University Hospital, College of Medicine, National Taiwan University, No. 7, Chung-Shan S. Rd., Taipei 100, Taiwan, ROC.
authors.forename: Patrick Chow-In
authors.initials: PC
authors.lastname: Ko
authors.forename: Wen-Jone
authors.initials: WJ
authors.lastname: Chen
authors.forename: Chih-Hao
authors.initials: CH
authors.lastname: Lin
authors.forename: Matthew Huei-Ming
authors.initials: MH
authors.lastname: Ma
authors.forename: Fang-Yue
authors.initials: FY
authors.lastname: Lin
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016887:Cardiopulmonary Resuscitation / Q000295:instrumentation / Q000706:statistics & numerical data*; D047548:Defibrillators / Q000706:statistics & numerical data*; D004562:Electrocardiography; D004632:Emergency Medical Services / Q000706:statistics & numerical data*; D005260:Female; D006323:Heart Arrest / Q000209:etiology / Q000628:therapy*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010043:Outcome and Process Assessment, Health Care; D016019:Survival Analysis; D013624:Taiwan; D016896:Treatment Outcome; D014693:Ventricular Fibrillation / Q000150:complications / Q000175:diagnosis