title: Comparison Between 30:1 and 30:2 Compression-to-ventilation Ratios for Cardiopulmonary Resuscitation: Are Two Ventilations Necessary?
abstract: OBJECTIVE
  Controversy is continuing over the need for ventilation and the optimal compression-ventilation (CV) ratio during cardiopulmonary resuscitation (CPR). The aim of this study was to comparatively elucidate the effect on hemodynamics and arterial oxygen saturation of a single ventilation relative to two consecutive ventilations during CPR in a dog model of cardiac arrest.
  
  
  METHODS
  Twenty mongrel dogs were divided into two groups. After 3 minutes of ventricular fibrillation (VF), the single-ventilation group received CPR with a 30:1 CV ratio, and the two-ventilation group received CPR with a 30:2 CV ratio, all with room air for 7 minutes. Thereafter, continuous chest compressions and intermittent ventilation at rate of 10 per minute were followed for both groups for 10 minutes. Hemodynamic parameters, arterial blood gas profiles, and variables from CPR were compared at baseline and at 5, 10, 15, and 20 minutes after induction of VF.
  
  
  RESULTS
  Hemodynamic parameters including aortic systolic and diastolic pressures, right atrial systolic and diastolic pressures, coronary perfusion pressure, end-tidal carbon dioxide tension, and arterial blood gas profiles including arterial oxygen tension, arterial oxygen saturation, and arterial carbon dioxide tension were not different between two groups during CPR. In the 30:1 group, the period of compression interruption was shorter and chest compression fraction was higher than that in the 30:2 group (6 sec/min vs. 10.9 sec/min, p < 0.001; 90.0% vs. 81.8%, p < 0.001).
  
  
  CONCLUSIONS
  CPR with a 30:1 CV ratio, compared to CPR with a 30:2 CV ratio, results in comparable arterial oxygenation saturation and hemodynamics.
authors.affiliation: Department of Emergency Medicine, Yonsei University Wonju College of Medicine, Wonju, Republic of Korea.
authors.forename: Kyoung-Chul
authors.initials: KC
authors.lastname: Cha
authors.affiliation: Department of Emergency Medicine, Yonsei University Wonju College of Medicine, Wonju, Republic of Korea.
authors.forename: Yong Won
authors.initials: YW
authors.lastname: Kim
authors.affiliation: Department of Emergency Medicine, Yonsei University Wonju College of Medicine, Wonju, Republic of Korea.
authors.forename: Tae Hoon
authors.initials: TH
authors.lastname: Kim
authors.affiliation: Department of Emergency Medicine, Yonsei University Wonju College of Medicine, Wonju, Republic of Korea.
authors.forename: Woo Jin
authors.initials: WJ
authors.lastname: Jung
authors.affiliation: Department of Emergency Medicine, Yonsei University Wonju College of Medicine, Wonju, Republic of Korea.
authors.forename: Hyun
authors.initials: H
authors.lastname: Yook
authors.affiliation: Institute of Lifestyle Medicine, Yonsei University Wonju College of Medicine, Wonju, Republic of Korea.
authors.forename: Eunhee
authors.initials: E
authors.lastname: Choi
authors.affiliation: Department of Emergency Medicine, Yonsei University Wonju College of Medicine, Wonju, Republic of Korea.
authors.forename: Yong Sung
authors.initials: YS
authors.lastname: Cha
authors.affiliation: Department of Emergency Medicine, Yonsei University Wonju College of Medicine, Wonju, Republic of Korea.
authors.forename: Oh Hyun
authors.initials: OH
authors.lastname: Kim
authors.affiliation: Department of Emergency Medicine, Yonsei University Wonju College of Medicine, Wonju, Republic of Korea.
authors.forename: Hyun
authors.initials: H
authors.lastname: Kim
authors.affiliation: Department of Emergency Medicine, Yonsei University Wonju College of Medicine, Wonju, Republic of Korea.
authors.forename: Kang Hyun
authors.initials: KH
authors.lastname: Lee
authors.affiliation: Department of Emergency Medicine, Yonsei University Wonju College of Medicine, Wonju, Republic of Korea.
authors.forename: Sung Oh
authors.initials: SO
authors.lastname: Hwang
mesh_terms: D000818:Animals; D001784:Blood Gas Analysis; D001794:Blood Pressure; D016887:Cardiopulmonary Resuscitation / Q000379:methods*; D004285:Dogs; D005260:Female; D006323:Heart Arrest / Q000150:complications / Q000628:therapy*; D006439:Hemodynamics; D008297:Male; D012121:Respiration, Artificial / Q000379:methods*; D014693:Ventricular Fibrillation / Q000209:etiology / Q000628:therapy*