title: Impact of early intravenous epinephrine administration on outcomes following out-of-hospital cardiac arrest.
abstract: BACKGROUND
  The effectiveness of epinephrine administration for cardiac arrests has been shown in animal models, but the clinical effect is still controversial.
  
  
  RESULTS
  A prospective, population-based, observational study in Osaka involved consecutive out-of-hospital cardiac arrest (OHCA) patients from January 2007 through December 2009. We evaluated the outcomes among adult non-traumatic bystander-witnessed OHCA patients for whom the local protocol directed the emergency medical service personnel to administer epinephrine. After stratifying by first documented cardiac rhythm, outcomes were compared among the following groups: non-administration, ≤10, 11-20 and ≥21 min as the time from emergency call to epinephrine administration. A total of 3,161 patients were eligible for our analyses, among whom 1,013 (32.0%) actually received epinephrine. The epinephrine group had a significantly lower rate of neurologically intact 1-month survival than the non-epinephrine group (4.1% vs. 6.1%, P=0.028). In cases of ventricular fibrillation (VF) arrest, patients in the early epinephrine group who received epinephrine administration within 10 min had a significantly higher rate of neurologically intact 1-month survival compared with the non-epinephrine group (66.7% vs. 24.9%), though other epinephrine groups did not. In cases of non-VF arrest, the rate of neurologically intact 1-month survival was low, irrespective of epinephrine administration.
  
  
  CONCLUSIONS
  The effectiveness of epinephrine after OHCA depends on the time of administration. When epinephrine is administered in the early phase, there is an improvement in neurological outcome from OHCA with VF.
authors.affiliation: Senri Critical Care Medical Center, Osaka Saiseikai Senri Hospital, Suita, Japan. yhayashi@senri.saiseikai.or.jp
authors.forename: Yasuyuki
authors.initials: Y
authors.lastname: Hayashi
authors.forename: Taku
authors.initials: T
authors.lastname: Iwami
authors.forename: Tetsuhisa
authors.initials: T
authors.lastname: Kitamura
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Nishiuchi
authors.forename: Kentaro
authors.initials: K
authors.lastname: Kajino
authors.forename: Tomohiko
authors.initials: T
authors.lastname: Sakai
authors.forename: Chika
authors.initials: C
authors.lastname: Nishiyama
authors.forename: Masahiko
authors.initials: M
authors.lastname: Nitta
authors.forename: Atsushi
authors.initials: A
authors.lastname: Hiraide
authors.forename: Tatsuro
authors.initials: T
authors.lastname: Kai
mesh_terms: D000322:Adrenergic Agonists / Q000008:administration & dosage*; D000368:Aged; D000369:Aged, 80 and over; D016009:Chi-Square Distribution; D016757:Death, Sudden, Cardiac / Q000209:etiology / Q000517:prevention & control*; D004334:Drug Administration Schedule; D004562:Electrocardiography; D004632:Emergency Medical Services; D004837:Epinephrine / Q000008:administration & dosage*; D005260:Female; D006801:Humans; D007275:Injections, Intravenous; D007564:Japan; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D009422:Nervous System Diseases / Q000209:etiology / Q000517:prevention & control; D016017:Odds Ratio; D058687:Out-of-Hospital Cardiac Arrest / Q000175:diagnosis / Q000188:drug therapy* / Q000209:etiology / Q000401:mortality; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012042:Registries; D018570:Risk Assessment; D012307:Risk Factors; D013997:Time Factors; D016896:Treatment Outcome; D014693:Ventricular Fibrillation / Q000150:complications
chemical_list: D000322:Adrenergic Agonists; D004837:Epinephrine