Use of heliox in critical upper airway obstruction. Physical and physiologic considerations in choosing the optimal helium:oxygen mix.
Heliox has a lower density than oxygen and nitrogen, and can improve ventilation rapidly in patients with critical upper airway obstruction. The choice of the best helium:oxygen ratio depends on whether the predominant problem is hypercarbia or hypoxia. In the former situation, 80% helium should be used, and in the latter, 100% oxygen is appropriate.
Ho
Anthony M H
AM
Department of Anaesthesia and Intensive Care, Faculty of Medicine, Prince of Wales Hospital Shatin, The Chinese University of Hong Kong, NT, Shatin, Hong Kong. hoamh@hotmail.com
Dion
Peter W
PW
Karmakar
Manoj K
MK
Chung
David C
DC
Tay
Beng A
BA
D000402:Airway Obstruction / Q000628:therapy*; D002245:Carbon Dioxide / Q000032:analysis; D006371:Helium / Q000008:administration & dosage*; D006801:Humans; D000860:Hypoxia / Q000628:therapy; D008962:Models, Theoretical; D010100:Oxygen / Q000008:administration & dosage*; D010313:Partial Pressure
D002245:Carbon Dioxide; D006371:Helium; C038949:heliox; D010100:Oxygen