title: Prolonged cardiopulmonary resuscitation and outcomes after out-of-hospital cardiac arrest.
abstract: It is unclear whether prolonged resuscitation can result in successful outcome following out-of-hospital cardiac arrests (OHCA). We assessed associations between duration of pre-hospital resuscitation on survival and functional outcome following OHCA in patients achieving pre-hospital return of spontaneous circulation (ROSC).
  
  
  
  We included 1316 adult OHCA individuals with pre-hospital ROSC (2005-2011) handled by the largest nationwide ambulance provider in Denmark. Patients were stratified into 0-5, 6-10, 11-15, 16-20, 21-25 and >25min of cardiopulmonary resuscitation (CPR) by emergency medical services until ROSC was achieved. Nursing home admission and diagnosis of anoxic brain damage were measured as proxies of poor neurological/functional outcomes.
  
  
  
  Median time from CPR initiation to ROSC was 12min (IQR: 7-18) while 20.4% achieved ROSC after >25min. Overall, 37.5% (494) of the study population achieved 30-day survival. Thirty-day survival was inversely related to minutes of CPR to ROSC: ranging from 59.6% (127/213) for ≤5min to 13.8% (19/138) for >25min. If bystander initiated CPR before ambulance arrival, corresponding values ranged from 70.4% (107/152) to 21.8% (12/55). Of 30-day survivors, patients discharged to own home rather than nursing home ranged from 95.0% (124/127) to 84.7% (18/19), respectively. Of 30-day survivors, patients discharged without diagnosis of anoxic brain damage ranged from 98.4% (125/127) to 73.7% (14/19) for corresponding intervals.
  
  
  
  Even those requiring prolonged resuscitation duration prior to ROSC had meaningful survival rates with the majority of survivors able to return to live in own homes. These data suggest that prolonged resuscitation is not futile.
authors.affiliation: Department of Cardiology, Copenhagen University Hospital Gentofte, Kildegårdvej 28, Post 635, 2900 Hellerup, Denmark. Electronic address: shahzleen@gmail.com.
authors.forename: Shahzleen
authors.initials: S
authors.lastname: Rajan
authors.affiliation: Department of Cardiology, Rigshospitalet, Copenhagen University Hospital, Blegdamsvej 9, 2100 Copenhagen, Denmark; Emergency Medical Services Copenhagen, University of Copenhagen, Telegrafvej 5, 2750 Ballerup, Denmark.
authors.forename: Fredrik
authors.initials: F
authors.lastname: Folke
authors.affiliation: Cardiovascular Research Center, Department of Anesthesiology, Aalborg University Hospital, Sdr. Skovvej 15, 9000 Aalborg, Denmark.
authors.forename: Kristian
authors.initials: K
authors.lastname: Kragholm
authors.affiliation: Department of Cardiology, Copenhagen University Hospital Gentofte, Kildegårdvej 28, Post 635, 2900 Hellerup, Denmark.
authors.forename: Carolina Malta
authors.initials: CM
authors.lastname: Hansen
authors.affiliation: Duke Clinical Research Institute, 2400 Pratt St, Durham, NC, USA.
authors.forename: Christopher B
authors.initials: CB
authors.lastname: Granger
authors.affiliation: Department of Health, Science and Technology, Aalborg University, Niels Jernes Vej 12, 9220 Aalborg, Denmark.
authors.forename: Steen Møller
authors.initials: SM
authors.lastname: Hansen
authors.affiliation: Duke Clinical Research Institute, 2400 Pratt St, Durham, NC, USA.
authors.forename: Eric D
authors.initials: ED
authors.lastname: Peterson
authors.affiliation: Emergency Medical Services Copenhagen, University of Copenhagen, Telegrafvej 5, 2750 Ballerup, Denmark.
authors.forename: Freddy K
authors.initials: FK
authors.lastname: Lippert
authors.affiliation: Department of Cardiology, Copenhagen University Hospital Gentofte, Kildegårdvej 28, Post 635, 2900 Hellerup, Denmark.
authors.forename: Kathrine B
authors.initials: KB
authors.lastname: Søndergaard
authors.affiliation: Department of Cardiology, Rigshospitalet, Copenhagen University Hospital, Blegdamsvej 9, 2100 Copenhagen, Denmark.
authors.forename: Lars
authors.initials: L
authors.lastname: Køber
authors.affiliation: The National Institute of Public Health, University of Southern Denmark, Øster Farimagsgade 5A, 1353 Copenhagen K, Denmark.
authors.forename: Gunnar H
authors.initials: GH
authors.lastname: Gislason
authors.affiliation: Department of Health, Science and Technology, Aalborg University, Niels Jernes Vej 12, 9220 Aalborg, Denmark.
authors.forename: Christian
authors.initials: C
authors.lastname: Torp-Pedersen
authors.affiliation: Department of Cardiology, Copenhagen University Hospital Gentofte, Kildegårdvej 28, Post 635, 2900 Hellerup, Denmark; Emergency Medical Services Copenhagen, University of Copenhagen, Telegrafvej 5, 2750 Ballerup, Denmark.
authors.forename: Mads
authors.initials: M
authors.lastname: Wissenberg
mesh_terms: D000368:Aged; D016887:Cardiopulmonary Resuscitation / Q000379:methods* / Q000401:mortality*; D004554:Electric Countershock; D004632:Emergency Medical Services / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D002534:Hypoxia, Brain / Q000209:etiology; D008297:Male; D018447:Medical Futility; D008875:Middle Aged; D058687:Out-of-Hospital Cardiac Arrest / Q000401:mortality* / Q000628:therapy*; D016019:Survival Analysis; D015996:Survival Rate; D013997:Time Factors
keywords: Cardiopulmonary resuscitation; Epidemiology; Prolonged resuscitation; Survival