WHY is already exhausted air bringing a person to their senses during artificial respiration? As we know, if you stay in an airtight room for a long time, you can suffocate, since during breathing the amount of oxygen in the air decreases and the amount of carbon dioxide increases. However, contrary to popular belief,
a person does not exhale pure carbon dioxide but a mixture of gases that contains 16-17% oxygen and about 4% carbon dioxide. (For comparison: atmospheric air, which is 21% oxygen, contains a negligible amount of carbon dioxide - 0.04%.)
This oxygen is enough to bring a person back to life by artificial respiration -
from mouth to mouth or from mouth to nose. Such stimulation sometimes takes a long time, up to an hour and a half.
@Health