title: Chest compression-only cardiopulmonary resuscitation for out-of-hospital cardiac arrest with public-access defibrillation: a nationwide cohort study.
abstract: BACKGROUND
  It remains unclear which is more effective to increase survival after out-of-hospital cardiac arrest in those with public-access defibrillation, bystander-initiated chest compression-only cardiopulmonary resuscitation (CPR) or conventional CPR with rescue breathing.
  
  
  RESULTS
  A nationwide, prospective, population-based observational study covering the whole population of Japan and involving consecutive out-of-hospital cardiac arrest patients with resuscitation attempts has been conducted since 2005. We enrolled all out-of-hospital cardiac arrests of presumed cardiac origin that were witnessed and received shocks with public-access automated external defibrillation (AEDs) by bystanders from January 1, 2005, to December 31, 2009. The main outcome measure was neurologically favorable 1-month survival. We compared outcomes by type of bystander-initiated CPR (chest compression-only CPR and conventional CPR with compressions and rescue breathing). Multivariable logistic regression was used to assess the relationship between the type of CPR and a better neurological outcome. During the 5 years, 1376 bystander-witnessed out-of-hospital cardiac arrests of cardiac origin in individuals who received CPR and shocks with public-access AEDs by bystanders were registered. Among them, 506 (36.8%) received chest compression-only CPR and 870 (63.2%) received conventional CPR. The chest compression-only CPR group (40.7%, 206 of 506) had a significantly higher rate of 1-month survival with favorable neurological outcome than the conventional CPR group (32.9%, 286 of 870; adjusted odds ratio, 1.33; 95% confidence interval, 1.03-1.70).
  
  
  CONCLUSIONS
  Compression-only CPR is more effective than conventional CPR for patients in whom out-of-hospital cardiac arrest is witnessed and shocked with public-access defibrillation. Compression-only CPR is the most likely scenario in which lay rescuers can witness a sudden collapse and use public-access AEDs.
authors.affiliation: Kyoto University Health Service, Yoshida Honmachi, Sakyo-ku, Kyoto 606-8501, Japan. iwamit@e-mail.jp
authors.forename: Taku
authors.initials: T
authors.lastname: Iwami
authors.forename: Tetsuhisa
authors.initials: T
authors.lastname: Kitamura
authors.forename: Takashi
authors.initials: T
authors.lastname: Kawamura
authors.forename: Hideo
authors.initials: H
authors.lastname: Mitamura
authors.forename: Ken
authors.initials: K
authors.lastname: Nagao
authors.forename: Morimasa
authors.initials: M
authors.lastname: Takayama
authors.forename: Yoshihiko
authors.initials: Y
authors.lastname: Seino
authors.forename: Hideharu
authors.initials: H
authors.lastname: Tanaka
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Nonogi
authors.forename: Naohiro
authors.initials: N
authors.lastname: Yonemoto
authors.forename: Takeshi
authors.initials: T
authors.lastname: Kimura
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016887:Cardiopulmonary Resuscitation / Q000379:methods / Q000706:statistics & numerical data*; D015331:Cohort Studies; D004554:Electric Countershock / Q000706:statistics & numerical data*; D005260:Female; D006336:Heart Massage / Q000379:methods / Q000706:statistics & numerical data*; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D058687:Out-of-Hospital Cardiac Arrest / Q000401:mortality* / Q000628:therapy*; D011446:Prospective Studies; D012042:Registries / Q000706:statistics & numerical data; D017180:Tachycardia, Ventricular / Q000401:mortality / Q000628:therapy; D014693:Ventricular Fibrillation / Q000401:mortality / Q000628:therapy; D055815:Young Adult