title: Cardiopulmonary resuscitation during severe hypothermia in pigs: does epinephrine or vasopressin increase coronary perfusion pressure?
abstract: The American Heart Association does not recommend epinephrine for management of hypothermic cardiac arrest if body core temperature is below 30 degrees C. Furthermore, the effects of vasopressin administration during hypothermic cardiac arrest are totally unknown. This study was designed to assess the effects of vasopressin and epinephrine on coronary perfusion pressure in a porcine model during hypothermic cardiac arrest cardiopulmonary resuscitation (CPR). Pigs were surface-cooled until their body core temperature was 26 degrees C. After 30 min of untreated cardiac arrest, followed by 3 min of basic life support CPR, 15 animals were randomly assigned to receive, at 5-min intervals, either vasopressin (0.4, 0.4, and 0.8 U/kg; n = 5), epinephrine (45, 45, and 200 microg/kg; n = 5), or saline placebo (n = 5). Compared with epinephrine, mean +/- SEM coronary perfusion pressure was significantly higher (P < 0.05) 90 s and 5 min after the first (35+/-4 vs 22+/-3 mm Hg and 37+/-2 vs 16+/-2 mm Hg) and the second vasopressin administration (40+/-5 vs 26+/-5 mm Hg and 36+/-5 vs 18+/-2 mm Hg, respectively). After the third drug administration, coronary perfusion pressure in the epinephrine group increased dramatically and was comparable to vasopressin. In the saline placebo group, coronary perfusion pressure was significantly lower (P < 0.05) than in the vasopressin and epinephrine groups. Six animals treated with epinephrine or vasopressin had transient return of spontaneous circulation, whereas all placebo animals died (P < 0.05). During CPR in severe hypothermia, administration of both vasopressin and epinephrine resulted in significant increases in coronary perfusion pressure when compared with placebo.
  
  
  CONCLUSIONS
  Our study was designed to assess the effects of vasopressin and epinephrine in a porcine model simulating cardiac arrest during severe hypothermia. This study demonstrates that the administration of both emergency drugs results in an increased perfusion pressure in the heart.
authors.affiliation: Department of Anesthesiology and Critical Care Medicine, Leopold-Franzens-University of Innsbruck, Austria. anette.krismer@uibk.ac.at
authors.forename: A C
authors.initials: AC
authors.lastname: Krismer
authors.forename: K H
authors.initials: KH
authors.lastname: Lindner
authors.forename: R
authors.initials: R
authors.lastname: Kornberger
authors.forename: V
authors.initials: V
authors.lastname: Wenzel
authors.forename: G
authors.initials: G
authors.lastname: Mueller
authors.forename: W
authors.initials: W
authors.lastname: Hund
authors.forename: S
authors.initials: S
authors.lastname: Oroszy
authors.forename: K G
authors.initials: KG
authors.lastname: Lurie
authors.forename: P
authors.initials: P
authors.lastname: Mair
mesh_terms: D000818:Animals; D001794:Blood Pressure / Q000187:drug effects*; D001831:Body Temperature / Q000187:drug effects / Q000502:physiology; D016887:Cardiopulmonary Resuscitation; D003326:Coronary Circulation / Q000187:drug effects*; D004837:Epinephrine / Q000627:therapeutic use*; D005260:Female; D006323:Heart Arrest / Q000473:pathology; D007035:Hypothermia / Q000628:therapy*; D008297:Male; D013552:Swine; D014662:Vasoconstrictor Agents / Q000627:therapeutic use*; D014667:Vasopressins / Q000627:therapeutic use*
chemical_list: D014662:Vasoconstrictor Agents; D014667:Vasopressins; D004837:Epinephrine