title: Prehospital surface cooling is safe and can reduce time to target temperature after cardiac arrest.
abstract: OBJECTIVE
  Mild therapeutic hypothermia proved to be beneficial when induced after cardiac arrest in humans. Prehospital cooling with i.v. fluids was associated with adverse side effects. Our primary objective was to compare time to target temperature of out-of hospital cardiac arrest patients cooled non-invasively either in the prehospital setting vs. the in-hospital (IH) setting, to assess surface-cooling safety profile and long term outcome.
  
  
  METHODS
  In this retrospective, single center cohort study, a group of adult patients with restoration of spontaneous circulation (ROSC) after out-of hospital cardiac arrest were cooled with a surface cooling pad beginning either in the prehospital or IH setting for 24h. Time to target temperature (33.9°C), temperature on admission, time to admission after ROSC and outcome were compared. Also, rearrests and pulmonary edema were assessed. Neurologic outcome at 12 months was evaluated (Cerebral Performance Category, CPC 1-2, favorable outcome).
  
  
  RESULTS
  Between September 2005 and February 2010, 56 prehospital cooled patients and 54 IH-cooled patients were treated. Target temperature was reached in 85 (66-117)min (prehospital) and in 135 (102-192)min (IH) after ROSC (p<0.001). After prehospital cooling, hospital admission temperature was 35.2 (34.2-35.8)°C, and in the IH-cooling patients initial temperature was 35.8 (35.2-36.3)°C (p=0.001). No difference in numbers of rearrests and pulmonary edema between groups was observed. In both groups, no skin lesions were observed. Favorable outcome was reached in 26.8% (prehospital) and in 37.0% (IH) of the patients (p=0.17).
  
  
  CONCLUSIONS
  Using a non-invasive prehospital surface cooling method after cardiac arrest, target temperature can be reached faster without any major complications than starting cooling IH. The effect of early non-invasive cooling on long-term outcome remains to be determined in larger studies.
authors.affiliation: Department of Emergency Medicine, Medical University of Vienna, Austria.
authors.forename: Thomas
authors.initials: T
authors.lastname: Uray
authors.affiliation: Department of Critical Care Medicine, University of Pittsburgh School of Medicine, PA, USA.
authors.forename: Florian B
authors.initials: FB
authors.lastname: Mayr
authors.affiliation: Department of Emergency Medicine, Medical University of Vienna, Austria.
authors.forename: Peter
authors.initials: P
authors.lastname: Stratil
authors.affiliation: Department of Emergency Medicine, Medical University of Vienna, Austria.
authors.forename: Stefan
authors.initials: S
authors.lastname: Aschauer
authors.affiliation: Department of Emergency Medicine, Medical University of Vienna, Austria.
authors.forename: Christoph
authors.initials: C
authors.lastname: Testori
authors.affiliation: Department of Emergency Medicine, Medical University of Vienna, Austria. Electronic address: fritz.sterz@meduniwien.ac.at.
authors.forename: Fritz
authors.initials: F
authors.lastname: Sterz
authors.affiliation: Department of Emergency Medicine, Medical University of Vienna, Austria.
authors.forename: Moritz
authors.initials: M
authors.lastname: Haugk
mesh_terms: D061605:Administration, Intravenous; D000368:Aged; D001831:Body Temperature; D016887:Cardiopulmonary Resuscitation / Q000379:methods; D015331:Cohort Studies; D057186:Comparative Effectiveness Research; D004632:Emergency Medical Services / Q000379:methods / Q000706:statistics & numerical data; D005260:Female; D005440:Fluid Therapy / Q000009:adverse effects / Q000379:methods; D006760:Hospitalization / Q000706:statistics & numerical data*; D006801:Humans; D007036:Hypothermia, Induced / Q000009:adverse effects / Q000295:instrumentation / Q000379:methods; D008297:Male; D008875:Middle Aged; D058687:Out-of-Hospital Cardiac Arrest / Q000503:physiopathology / Q000628:therapy; D017063:Outcome Assessment, Health Care; D012189:Retrospective Studies; D014481:United States
keywords: Ambulances; Body temperature; Cardiopulmonary resuscitation (CPR); Emergency medical services; Hypothermia, induced; Out-of-hospital cardiac arrest