title: Influence of Acute Normobaric Hypoxia on Hemostasis in Volunteers with and without Acute Mountain Sickness.
abstract: BACKGROUND
  The aim of the present study was to investigate whether a 12-hour exposure in a normobaric hypoxic chamber would induce changes in the hemostatic system and a procoagulant state in volunteers suffering from acute mountain sickness (AMS) and healthy controls.
  
  
  METHODS
  37 healthy participants were passively exposed to 12.6% FiO2 (simulated altitude hypoxia of 4,500 m). AMS development was investigated by the Lake Louise Score (LLS). Prothrombin time, activated partial thromboplastin time, fibrinogen, and platelet count were measured and specific methods (i.e., thromboelastometry and a thrombin generation test) were used.
  
  
  RESULTS
  AMS prevalence was 62.2% (LLS cut off of 3). For the whole group, paired sample t-tests showed significant increase in the maximal concentration of generated thrombin. ROTEM measurements revealed a significant shortening of coagulation time and an increase of maximal clot firmness (InTEM test). A significant increase in maximum clot firmness could be shown (FibTEM test).
  
  
  CONCLUSIONS
  All significant changes in coagulation parameters after exposure remained within normal reference ranges. No differences with regard to measured parameters of the hemostatic system between AMS-positive and -negative subjects were observed. Therefore, the hypothesis of the acute activation of coagulation by hypoxia can be rejected.
authors.affiliation: Institute for Sports Medicine, Alpine Medicine and Health Tourism, University for Health Sciences, Medical Informatics and Technology (UMIT), Eduard-Wallnöfer-Zentrum 1, 6060 Hall, Austria.
authors.forename: Marc
authors.initials: M
authors.lastname: Schaber
authors.affiliation: Institute for Sports Medicine, Alpine Medicine and Health Tourism, University for Health Sciences, Medical Informatics and Technology (UMIT), Eduard-Wallnöfer-Zentrum 1, 6060 Hall, Austria.
authors.forename: Veronika
authors.initials: V
authors.lastname: Leichtfried
authors.affiliation: Department for General and Surgical Critical Care Medicine, Medical University of Innsbruck, Anichstrasse 35, 6020 Innsbruck, Austria.
authors.forename: Dietmar
authors.initials: D
authors.lastname: Fries
authors.affiliation: Department of Sports Science, Leopold Franzens University Innsbruck, Fürstenweg 185, 6020 Innsbruck, Austria.
authors.forename: Maria
authors.initials: M
authors.lastname: Wille
authors.affiliation: Department of Sports Science, Leopold Franzens University Innsbruck, Fürstenweg 185, 6020 Innsbruck, Austria.
authors.forename: Hannes
authors.initials: H
authors.lastname: Gatterer
authors.affiliation: Department of Sports Science, Leopold Franzens University Innsbruck, Fürstenweg 185, 6020 Innsbruck, Austria.
authors.forename: Martin
authors.initials: M
authors.lastname: Faulhaber
authors.affiliation: Central Institute for Medical and Chemical Laboratory Diagnosis, Medical University of Innsbruck, Anichstrasse 35, 6020 Innsbruck, Austria.
authors.forename: Philipp
authors.initials: P
authors.lastname: Würtinger
authors.affiliation: Institute for Sports Medicine, Alpine Medicine and Health Tourism, Tirol Kliniken Innsbruck and University for Health Sciences, Medical Informatics and Technology (UMIT), Eduard-Wallnöfer-Zentrum 1, 6060 Hall, Austria.
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Schobersberger
mesh_terms: D000208:Acute Disease; D000532:Altitude Sickness / Q000150:complications / Q000503:physiopathology*; D001777:Blood Coagulation; D005260:Female; D005342:Fibrinolysis; D006487:Hemostasis; D006801:Humans; D000860:Hypoxia / Q000150:complications / Q000503:physiopathology*; D008297:Male; D010100:Oxygen / Q000378:metabolism*; D010101:Oxygen Consumption
chemical_list: D010100:Oxygen