Use of heliox in critical upper airway obstruction. Physical and physiologic considerations in choosing the optimal helium:oxygen mix

Resuscitation. 2002 Mar;52(3):297-300. doi: 10.1016/s0300-9572(01)00473-7.


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.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Airway Obstruction / therapy*
  • Carbon Dioxide / analysis
  • Helium / administration & dosage*
  • Humans
  • Hypoxia / therapy
  • Models, Theoretical
  • Oxygen / administration & dosage*
  • Partial Pressure


  • Carbon Dioxide
  • Helium
  • heliox
  • Oxygen