title: Duration of ventilations during cardiopulmonary resuscitation by lay rescuers and first responders: relationship between delivering chest compressions and outcomes.
abstract: BACKGROUND
  The 2010 guidelines for cardiopulmonary resuscitation allow 5 seconds to give 2 breaths to deliver sufficient chest compressions and to keep perfusion pressure high. This study aims to determine whether the recommended short interruption for ventilations by trained lay rescuers and first responders can be achieved and to evaluate its consequence for chest compressions and survival.
  
  
  RESULTS
  From a prospective data collection of out-of-hospital cardiac arrest, we used automatic external defibrillator recordings of cardiopulmonary resuscitation by rescuers who had received a standard European Resuscitation Council basic life support and automatic external defibrillator course. Ventilation periods and total compressions delivered per minute during each 2 minutes of cardiopulmonary resuscitation cycle were measured, and the chest compression fraction was calculated. Neurological intact survival to discharge was studied in relation to these factors and covariates. We included 199 automatic external defibrillator recordings. The median interruption time for 2 ventilations was 7 seconds (25th-75th percentile, 6-9 seconds). Of all rescuers, 21% took <5 seconds and 83% took <10 seconds for a ventilation period; 97%, 88%, and 63% of rescuers were able to deliver >60, >70, and >80 chest compressions per minute, respectively. The median chest compression fraction was 65% (25th-75th percentile, 59%-71%). Survival was 25% (49 of 199), not associated with long or short ventilation pauses when controlled for covariates.
  
  
  CONCLUSIONS
  The great majority of rescuers can give 2 rescue breaths in <10 seconds and deliver at least 70 compressions in a minute. Longer pauses for ventilations are not associated with worse outcome. Guidelines may allow longer pauses for ventilations with no detriment to survival.
authors.affiliation: Msc, Department of Cardiology, Room G4-248, Academic Medical Center, University of Amsterdam, Meibergdreef 9 1105 AZ, Amsterdam, The Netherlands. s.g.beesems@amc.nl
authors.forename: Stefanie G
authors.initials: SG
authors.lastname: Beesems
authors.forename: Lizzy
authors.initials: L
authors.lastname: Wijmans
authors.forename: Jan G P
authors.initials: JG
authors.lastname: Tijssen
authors.forename: Rudolph W
authors.initials: RW
authors.lastname: Koster
mesh_terms: D000368:Aged; D000572:American Heart Association; D001925:Brain Damage, Chronic / Q000453:epidemiology / Q000517:prevention & control; D016887:Cardiopulmonary Resuscitation / Q000193:education / Q000379:methods / Q000592:standards / Q000706:statistics & numerical data*; D047548:Defibrillators; D060731:Emergency Responders / Q000706:statistics & numerical data*; D005062:European Union; D005260:Female; D061388:Firefighters / Q000706:statistics & numerical data; D006336:Heart Massage; D006801:Humans; D002534:Hypoxia, Brain / Q000209:etiology / Q000517:prevention & control; D008297:Male; D008875:Middle Aged; D009426:Netherlands / Q000453:epidemiology; D058687:Out-of-Hospital Cardiac Arrest / Q000401:mortality / Q000628:therapy*; D016495:Police / Q000706:statistics & numerical data; D017410:Practice Guidelines as Topic; D011446:Prospective Studies; D012042:Registries; D012121:Respiration, Artificial; D015996:Survival Rate; D013997:Time Factors; D014481:United States