title: Evaluation of hemodynamic effects of xenon in dogs undergoing hemorrhagic shock.
abstract: OBJECTIVE
  The anesthetic gas xenon is reported to preserve hemodynamic stability during general anesthesia. However, the effects of the gas during shock are unclear. The objective of this study was to evaluate the effect of Xe on hemodynamic stability and tissue perfusion in a canine model of hemorrhagic shock.
  
  
  METHODS
  Twenty-six dogs, mechanically ventilated with a fraction of inspired oxygen of 21% and anesthetized with etomidate and vecuronium, were randomized into Xenon (Xe; n = 13) or Control (C; n = 13) groups. Following hemodynamic monitoring, a pressure-driven shock was induced to reach an arterial pressure of 40 mmHg. Hemodynamic data and blood samples were collected prior to bleeding, immediately after bleeding and 5, 20 and 40 minutes following shock. The Xe group was treated with 79% Xe diluted in ambient air, inhaled for 20 minutes after shock.
  
  
  RESULTS
  The mean bleeding volume was 44 mL.kg-1 in the C group and 40 mL.kg-1 in the Xe group. Hemorrhage promoted a decrease in both the cardiac index (p<0.001) and mean arterial pressure (p<0.001). These changes were associated with an increase in lactate levels and worsening of oxygen transport variables in both groups (p<0.05). Inhalation of xenon did not cause further worsening of hemodynamics or tissue perfusion markers.
  
  
  CONCLUSIONS
  Xenon did not alter hemodynamic stability or tissue perfusion in an experimentally controlled hemorrhagic shock model. However, further studies are necessary to validate this drug in other contexts.
authors.affiliation: Hospital das Clínicas da Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP, Brazil.
authors.forename: Ruben C
authors.initials: RC
authors.lastname: Franceschi
authors.forename: Luiz
authors.initials: L
authors.lastname: Malbouisson
authors.forename: Eduardo
authors.initials: E
authors.lastname: Yoshinaga
authors.forename: Jose Otavio Costa
authors.initials: JO
authors.lastname: Auler
authors.forename: Luiz Francisco Poli de
authors.initials: LF
authors.lastname: Figueiredo
authors.forename: Maria Jose C
authors.initials: MJ
authors.lastname: Carmona
mesh_terms: D018685:Anesthetics, Inhalation / Q000494:pharmacology*; D000818:Animals; D004285:Dogs; D006439:Hemodynamics / Q000187:drug effects*; D008297:Male; D023421:Models, Animal; D010477:Perfusion; D011897:Random Allocation; D012119:Respiration / Q000187:drug effects; D012771:Shock, Hemorrhagic; D013997:Time Factors; D016896:Treatment Outcome; D014978:Xenon / Q000494:pharmacology*
chemical_list: D018685:Anesthetics, Inhalation; D014978:Xenon