– If humans breathe in oxygen and exhale CO2, then why does mouth-to-mouth resuscitation work?

Question

– If humans breathe in oxygen and exhale CO2, then why does mouth-to-mouth resuscitation work?

In: 172

Answer 1

Basically, the “breathe in oxygen breath out CO2” line is an over simplification

Your lungs turn Oxygen into CO2. That doesn’t mean they’re 100% efficient at it.

The air you breathe in is 21% oxygen

The air you breathe out is still 16% oxygen

This is why you can hold your breath for a minute or two; you still have oxygen in your lungs, just less than is comfortable.

In the case of CPR life breaths, comfort isn’t really your first perrogative. You possibly even broke some ribs during the chest compressions anyway.