Comments on: When You Are Doing Cpr, Why Do You Breathe Into The Mouth Of The Victim, Don’t You Breathe Out Carbon Dioxide?

By: m

Tue, 13 Oct 2009 19:20:50 +0000

Agree with Aiden

By: Steve M

Steve M — Tue, 13 Oct 2009 15:44:46 +0000

Well, the patient has no air in their lungs and the only way to get direct air into the lungs with out the aid of a hospital or ambulance kitted air bag is through briefing into their lungs.

By: W W D

W W D — Tue, 13 Oct 2009 14:05:54 +0000

There’s a little less oxygen and a little more carbon dioxide in exhaled breaths than in the atmosphere, but the idea is that it’s better than nothing. If you’d like to carry around a laryngoscope, endotracheal tubes, and oxygen tank all the time just in case, that might be a better alternative, but it would probably get a little old.

By: Jay Jay

Jay Jay — Tue, 13 Oct 2009 10:45:26 +0000

You also breathe out a significant amount of O2. However, EMTs and other trained personal set up masks that are attached to a bag that pushes air into the patient. You can hook this mask up to pure O2. That’s usually better, and that’s what you’ll get in case of an emergency

By: Dave

Dave — Tue, 13 Oct 2009 06:23:36 +0000

The lungs only absorb about 16% of the oxygen breathed in meaning that there is still oxygen left in exhailed air.

By: Frank P

Frank P — Tue, 13 Oct 2009 00:45:35 +0000

You are inflating the lungs by using your breath, and the amount of CO2 is minimal in comparison to the benefit of forcing O2 into the lungs of a person who isn’t breathing. The action on the chest of the person who is giving CPR is to work the heart so that the blood is being circulated in the system. Without this action the entire activity of CPR is worthless. The object is to get blood that is carrying O2 to the brain and keep it alive until medical intervention is available. Regards Fap

By: csbiup

csbiup — Mon, 12 Oct 2009 21:54:42 +0000

it’s not all CO2. There’s enough O2 left to oxygenate the person’s blood. Basically some is better than nothing.

By: Irish Eyes

Irish Eyes — Mon, 12 Oct 2009 21:08:31 +0000

Aidens answer is the best

By: John H

John H — Mon, 12 Oct 2009 19:32:24 +0000

When you breathe you don’t absorb ALL the oxygen in the air. Your lungs only absorb some 16% of the oxygen you breathed in. The remaining 84% is more than enough for the victim to get his share. It’s sort of like the same reason a crowd doesn’t suffocate immediately when put in an unventilated room.

By: Aiden

Aiden — Mon, 12 Oct 2009 12:37:40 +0000

Your exhaled breath contains both O2 and CO2 … the O2 concentration of the surrounding environment (i.e. “room air”) is ~ 21% O2, so when we breathe in, our “fraction of inspired oxygen, or FiO2″ is ~ 21% (or .21).
Most atmospheric air (~78%) is nitrogen, ~21% oxygen, and ~ 1% CO2 … (the remainder is a mixture of all other gases).
When we breathe out, our “fraction of exhaled O2, or FeO2″ is ~ 16% – 18% O2.
The point is, exhaled air had a different composition, you’re right (more CO2, less O2) … but it still contains about 80% of the oxygen we breathe in.
I used to teach CPR and I used to advise students to take in two large breaths of air to increase their FeO2 prior to giving breaths … this isn’t necessary though — *some* oxygen beats none!