title: The time dependent association of adrenaline administration and survival from out-of-hospital cardiac arrest.
abstract: BACKGROUND
  Recommended for decades, the therapeutic value of adrenaline (epinephrine) in the resuscitation of patients with out-of-hospital cardiac arrest (OHCA) is controversial.
  
  
  OBJECTIVE
  To investigate the possible time-dependent outcomes associated with adrenaline administration by Emergency Medical Services personnel (EMS).
  
  
  METHODS
  A retrospective analysis of prospectively collected data from a near statewide cardiac resuscitation database between 1 January 2005 and 30 November 2013. Multivariable logistic regression was used to analyze the effect of the time interval between EMS dispatch and the initial dose of adrenaline on survival. The primary endpoints were survival to hospital discharge and favourable neurologic outcome.
  
  
  RESULTS
  Data from 3469 patients with witnessed OHCA were analyzed. Their mean age was 66.3 years and 69% were male. An initially shockable rhythm was present in 41.8% of patients. Based on a multivariable logistic regression model with initial adrenaline administration time interval (AATI) from EMS dispatch as the covariate, survival was greatest when adrenaline was administered very early but decreased rapidly with increasing (AATI); odds ratio 0.94 (95% Confidence Interval (CI) 0.92-0.97). The AATI had no significant effect on good neurological outcome (OR=0.96, 95% CI=0.90-1.02).
  
  
  CONCLUSIONS
  In patients with OHCA, survival to hospital discharge was greater in those treated early with adrenaline by EMS especially in the subset of patients with a shockable rhythm. However survival rapidly decreased with increasing adrenaline administration time intervals (AATI).
authors: Department of Medicine, University of Arizona Sarver Heart Center, Tucson, AZ, United States; Department of Medicine, University of Arizona College of Medicine, Tucson, AZ, United States; Department of Medicine, University of Arizona College of Medicine, Phoenix, AZ, United States. Electronic address: gaewy1933@gmail.com.
authors: Gordon A
authors: GA
authors: Ewy
authors: Department of Medicine, University of Arizona Sarver Heart Center, Tucson, AZ, United States; Department of Emergency Medicine, University of Arizona College of Medicine, Phoenix, AZ, United States; Bureau of EMS and Trauma System, Arizona Department of Health Services, Phoenix, AZ, United States.
authors: Bentley J
authors: BJ
authors: Bobrow
authors: Bureau of EMS and Trauma System, Arizona Department of Health Services, Phoenix, AZ, United States.
authors: Vatsal
authors: V
authors: Chikani
authors: Department of Medicine, University of Arizona Sarver Heart Center, Tucson, AZ, United States; Department of Emergency Medicine, University of Arizona College of Medicine, Tucson, AZ, United States; Department of Emergency Medicine, University of Arizona College of Medicine, Phoenix, AZ, United States.
authors: Arthur B
authors: AB
authors: Sanders
authors: Department of Medicine, University of Arizona Sarver Heart Center, Tucson, AZ, United States; Department of Anesthesiology, University of Arizona College of Medicine, Tucson, AZ, United States; Department of Anesthesiology, University of Arizona College of Medicine, Phoenix, AZ, United States.
authors: Charles W
authors: CW
authors: Otto
authors: Department of Emergency Medicine, University of Arizona College of Medicine, Tucson, AZ, United States; Department of Emergency Medicine, University of Arizona College of Medicine, Phoenix, AZ, United States.
authors: Daniel W
authors: DW
authors: Spaite
authors: Department of Medicine, University of Arizona Sarver Heart Center, Tucson, AZ, United States; Department of Medicine, University of Arizona College of Medicine, Tucson, AZ, United States; Department of Medicine, University of Arizona College of Medicine, Phoenix, AZ, United States.
authors: Karl B
authors: KB
authors: Kern
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001130:Arizona / Q000453:epidemiology; D016887:Cardiopulmonary Resuscitation / Q000379:methods*; D002648:Child; D004305:Dose-Response Relationship, Drug; D004632:Emergency Medical Services / Q000379:methods*; D004837:Epinephrine / Q000008:administration & dosage*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007275:Injections, Intravenous; D008297:Male; D008875:Middle Aged; D058687:Out-of-Hospital Cardiac Arrest / Q000401:mortality / Q000628:therapy*; D012042:Registries; D012189:Retrospective Studies; D015996:Survival Rate / Q000639:trends; D013566:Sympathomimetics / Q000008:administration & dosage; D013997:Time Factors; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D013566:Sympathomimetics; D004837:Epinephrine
keywords: Asystole; Cardiac arrest; Emergency medical services; Epinephrine; Pulseless electrical activity; Ventricular fibrillation