title: Trial of Continuous or Interrupted Chest Compressions during CPR.
abstract: BACKGROUND
  During cardiopulmonary resuscitation (CPR) in patients with out-of-hospital cardiac arrest, the interruption of manual chest compressions for rescue breathing reduces blood flow and possibly survival. We assessed whether outcomes after continuous compressions with positive-pressure ventilation differed from those after compressions that were interrupted for ventilations at a ratio of 30 compressions to two ventilations.
  
  
  METHODS
  This cluster-randomized trial with crossover included 114 emergency medical service (EMS) agencies. Adults with non-trauma-related cardiac arrest who were treated by EMS providers received continuous chest compressions (intervention group) or interrupted chest compressions (control group). The primary outcome was the rate of survival to hospital discharge. Secondary outcomes included the modified Rankin scale score (on a scale from 0 to 6, with a score of ≤3 indicating favorable neurologic function). CPR process was measured to assess compliance.
  
  
  RESULTS
  Of 23,711 patients included in the primary analysis, 12,653 were assigned to the intervention group and 11,058 to the control group. A total of 1129 of 12,613 patients with available data (9.0%) in the intervention group and 1072 of 11,035 with available data (9.7%) in the control group survived until discharge (difference, -0.7 percentage points; 95% confidence interval [CI], -1.5 to 0.1; P=0.07); 7.0% of the patients in the intervention group and 7.7% of those in the control group survived with favorable neurologic function at discharge (difference, -0.6 percentage points; 95% CI, -1.4 to 0.1, P=0.09). Hospital-free survival was significantly shorter in the intervention group than in the control group (mean difference, -0.2 days; 95% CI, -0.3 to -0.1; P=0.004).
  
  
  CONCLUSIONS
  In patients with out-of-hospital cardiac arrest, continuous chest compressions during CPR performed by EMS providers did not result in significantly higher rates of survival or favorable neurologic function than did interrupted chest compressions. (Funded by the National Heart, Lung, and Blood Institute and others; ROC CCC ClinicalTrials.gov number, NCT01372748.).
authors.affiliation: From the University of Washington-Harborview Center for Prehospital Emergency Care (G.N.) and Clinical Trial Center (G.N., B.L., R.H.S., S.M.) and Seattle-King County Center for Resuscitation Research, University of Washington (P.K., T.D.R.) - all in Seattle; University of Alabama School of Medicine (H.W., S.S.) and Birmingham Fire and Rescue Service (J.R.) - both in Birmingham; Pittsburgh Resuscitation Network, University of Pittsburgh, Pittsburgh (C.W.C., J. Condle); National Heart, Lung, and Blood Institute, Bethesda (G.S., D.E.), and Johns Hopkins University School of Medicine, Baltimore (M.W.) - both in Maryland; Ottawa/Ontario Prehospital Advanced Life Support Resuscitation Outcomes Consortium, Ottawa Hospital Research Institute, University of Ottawa, Ottawa (I.S., C.V.), Li Ka Shing Knowledge Institute, St. Michael's Hospital, University of Toronto, Toronto (L.J.M., S.C.), and the University of British Columbia, Vancouver (J. Christenson, R.S.) - all in Canada; the Department of Emergency Medicine, Medical College of Wisconsin, Milwaukee (T.P.A., R.C.); Dallas-Fort Worth Center for Resuscitation Research, University of Texas Southwestern Medical Center, Dallas (A.H.I., M.I.); and Virginia Commonwealth University Health System, Richmond (J.P.O.).
authors.forename: Graham
authors.initials: G
authors.lastname: Nichol
authors.forename: Brian
authors.initials: B
authors.lastname: Leroux
authors.forename: Henry
authors.initials: H
authors.lastname: Wang
authors.forename: Clifton W
authors.initials: CW
authors.lastname: Callaway
authors.forename: George
authors.initials: G
authors.lastname: Sopko
authors.forename: Myron
authors.initials: M
authors.lastname: Weisfeldt
authors.forename: Ian
authors.initials: I
authors.lastname: Stiell
authors.forename: Laurie J
authors.initials: LJ
authors.lastname: Morrison
authors.forename: Tom P
authors.initials: TP
authors.lastname: Aufderheide
authors.forename: Sheldon
authors.initials: S
authors.lastname: Cheskes
authors.forename: Jim
authors.initials: J
authors.lastname: Christenson
authors.forename: Peter
authors.initials: P
authors.lastname: Kudenchuk
authors.forename: Christian
authors.initials: C
authors.lastname: Vaillancourt
authors.forename: Thomas D
authors.initials: TD
authors.lastname: Rea
authors.forename: Ahamed H
authors.initials: AH
authors.lastname: Idris
authors.forename: Riccardo
authors.initials: R
authors.lastname: Colella
authors.forename: Marshal
authors.initials: M
authors.lastname: Isaacs
authors.forename: Ron
authors.initials: R
authors.lastname: Straight
authors.forename: Shannon
authors.initials: S
authors.lastname: Stephens
authors.forename: Joe
authors.initials: J
authors.lastname: Richardson
authors.forename: Joe
authors.initials: J
authors.lastname: Condle
authors.forename: Robert H
authors.initials: RH
authors.lastname: Schmicker
authors.forename: Debra
authors.initials: D
authors.lastname: Egan
authors.forename: Susanne
authors.initials: S
authors.lastname: May
authors.forename: Joseph P
authors.initials: JP
authors.lastname: Ornato
mesh_terms: D000328:Adult; D000368:Aged; D016887:Cardiopulmonary Resuscitation / Q000379:methods*; D003131:Combined Modality Therapy; D018592:Cross-Over Studies; D004632:Emergency Medical Services; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D058687:Out-of-Hospital Cardiac Arrest / Q000401:mortality / Q000628:therapy*; D011175:Positive-Pressure Respiration; D015996:Survival Rate; D061665:Time-to-Treatment; D014662:Vasoconstrictor Agents / Q000627:therapeutic use
chemical_list: D014662:Vasoconstrictor Agents