helium

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helium

 (He) [he´le-um]
a chemical element, atomic number 2, atomic weight 4.003. (See Appendix 6.) Helium is a chemically inert element that is odorless, tasteless, and noncombustible. Because of its low density it is easily moved through the air passages and therefore requires little effort in breathing on the part of the patient in respiratory distress. Although helium itself has no chemical therapeutic value, when combined with oxygen it facilitates delivery of oxygen to the lungs (see helium-oxygen therapy). It should be noted that helium causes the voice to be high-pitched and the spoken word difficult to understand. This should be explained to the patient with the assurance that the effect is harmless and temporary.
helium-oxygen therapy the administration of a mixture of helium and oxygen (commonly 80 per cent He and 20 per cent O2, or 70 per cent He and 30 per cent O2); used in the management of airway obstruction associated with bronchospasm or bronchial asthma. The He-O2 mixture is about one third the density of air. This reduces turbulent flow and the patient effort required for ventilation.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.

he·li·um (He),

(hē'lē-ŭm),
A gaseous element present in minute amounts in the atmosphere (0.000524% of dry volume); atomic no. 2, atomic wt. 4.002602; used as a diluent of medicinal gases; used as a diluent of oxygen principally in nonmedical applications, and in its liquid form as the coolant for super-conducting magnets (as in magnetic resonance imaging).
[G. hēlios, the sun]
Farlex Partner Medical Dictionary © Farlex 2012

he·li·um

(hē'lē-ŭm)
A gaseous element present in minute amounts in the atmosphere (0.000524% of dry volume); atomic no. 2, atomic wt. 4.002602; used as a diluent of medicinal gases, particularly oxygen.
[G. hēlios, the sun]
Medical Dictionary for the Health Professions and Nursing © Farlex 2012

he·li·um

(He) (hē'lē-ŭm)
A gaseous element present in minute amounts in the atmosphere used as a diluent of medicinal gases.
[G. hēlios, the sun]
Medical Dictionary for the Dental Professions © Farlex 2012
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