Heliox

This article is about the breathing gas. For the cryogenic system, see Heliox (cryogenic equipment).
Heliox
Identifiers
CAS Number
PubChem CID
Chemical and physical data
FormulaHe.O2
Molar mass36.001

Heliox is a breathing gas mixture of helium (He) and oxygen (O2). It is used as a medical treatment for patients with difficulty breathing because this mixture generates less resistance than atmospheric air when passing through the airways of the lungs, and thus requires less effort by a patient to breathe in and out of the lungs. It is also used as a breathing gas diluent for deep ambient pressure diving as it is not narcotic at high pressure, and for its low work of breathing.

Heliox has been used medically since the 1930s, and although the medical community adopted it initially to alleviate symptoms of upper airway obstruction, its range of medical uses has since expanded greatly, mostly because of the low density of the gas.[1][2] Heliox is also used in saturation diving and sometimes during the deep phase of technical dives.[3][4][5]

  1. ^ Barach AL, Eckman M (January 1936). "The effects of inhalation of helium mixed with oxygen on the mechanics of respiration". The Journal of Clinical Investigation. 15 (1): 47–61. doi:10.1172/JCI100758. PMC 424760. PMID 16694380.
  2. ^ "Heliox product information". BOC Medical. Archived from the original on 21 November 2008.
  3. ^ US Navy Diving Manual, 6th revision. United States: US Naval Sea Systems Command. 2008. Archived from the original on 2008-05-02. Retrieved 2008-07-08.
  4. ^ Brubakk AO, Neuman TS (2003). Bennett and Elliott's physiology and medicine of diving (5th Rev ed.). United States: Saunders Ltd. p. 800. ISBN 0-7020-2571-2.
  5. ^ "COMEX PRO".