title: Variable effects of high-dose adrenaline relative to standard-dose adrenaline on resuscitation outcomes according to cardiac arrest duration.
abstract: OBJECTIVE
  Adjustment of adrenaline (epinephrine) dosage according to cardiac arrest (CA) duration, rather than administering the same dose, may theoretically improve resuscitation outcomes. We evaluated variable effects of high-dose adrenaline (HDA) relative to standard-dose adrenaline (SDA) on resuscitation outcomes according to CA duration.
  
  
  METHODS
  Twenty-eight male domestic pigs were randomised to the following 4 groups according to the dosage of adrenaline (SDA 0.02 mg/kg vs. HDA 0.2mg/kg) and duration of CA before beginning cardiopulmonary resuscitation (CPR): 6 min SDA, 6 min HDA, 13 min SDA, or 13 min HDA. After the predetermined duration of untreated ventricular fibrillation, CPR was provided.
  
  
  RESULTS
  All animals in the 6 min SDA, 6 min HDA, and 13 min HDA groups were successfully resuscitated, while only 4 of 7 pigs in the 13 min SDA group were successfully resuscitated (p=0.043). HDA groups showed higher right atrial pressure, more frequent ventricular ectopic beats, higher blood glucose, higher troponin-I, and more severe metabolic acidosis than SDA groups. Animals of 13 min groups showed more severe metabolic acidosis and higher troponin-I than animals of 6 min groups. All successfully resuscitated animals, except two animals in the 13 min HDA group, survived for 7 days (p=0.121). Neurologic deficit score was not affected by the dose of adrenaline.
  
  
  CONCLUSIONS
  HDA showed benefit in achieving restoration of spontaneous circulation in 13 min CA, when compared with 6 min CA. However, this benefit did not translate into improved long-term survival or neurologic outcome.
authors.affiliation: Department of Emergency Medicine, Chonnam National University Hospital 671, Jebongno, Donggu, Gwangju, Republic of Korea. neoneti@hanmail.net
authors.forename: Kyung Woon
authors.initials: KW
authors.lastname: Jeung
authors.forename: Hyun Ho
authors.initials: HH
authors.lastname: Ryu
authors.forename: Kyung Hwan
authors.initials: KH
authors.lastname: Song
authors.forename: Byung Kook
authors.initials: BK
authors.lastname: Lee
authors.forename: Hyoung Youn
authors.initials: HY
authors.lastname: Lee
authors.forename: Tag
authors.initials: T
authors.lastname: Heo
authors.forename: Yong Il
authors.initials: YI
authors.lastname: Min
mesh_terms: D000818:Animals; D016887:Cardiopulmonary Resuscitation / Q000379:methods*; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D004837:Epinephrine / Q000008:administration & dosage*; D005500:Follow-Up Studies; D006323:Heart Arrest / Q000503:physiopathology / Q000628:therapy*; D006439:Hemodynamics / Q000187:drug effects*; D008297:Male; D020127:Recovery of Function / Q000187:drug effects*; D013552:Swine; D013997:Time Factors; D016896:Treatment Outcome; D014662:Vasoconstrictor Agents / Q000008:administration & dosage
chemical_list: D014662:Vasoconstrictor Agents; D004837:Epinephrine