Helium must always be combined with at least how much O2?
a. 20%
b. 30%
c. 40%
d. 50%
ANS: A
He must always be combined with at least 20% O2. The higher the concentration of O2 used in a heliox mixture, the less likely it is that heliox would be beneficial. Heliox mixtures of less than 60% He are rarely used clinically.
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An elderly female fell down three steps and now complains of back pain. After performing the primary assessment, which question would be most important to ask first?
A) "Did you become dizzy and fall or slip and then fall?" B) "Why did you not use the ramp on the other side?" C) "Do you have a history of high blood pressure?" D) "Which medications are you taking?"