how is mouth to mouth (CPR) beneficial if you’re blowing carbon dioxide into their lungs?

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In: Biology

Answer 1

Human lungs are not all that efficient. The air you exhale has less oxygen and more CO2, but it’s actually still breathable. You can even repeat that for a few cycles before it becomes a problem, though it does eventually. Some scuba divers take advantage of this, using machines called *rebreathers* to make their air supply last longer.