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Biology/Mouth-to-mouth resuscitation

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Expert: Florence M Rollwagen - 11/9/2008


Question
During mouth-to-mouth resuscitation, after the rescuer breathes through the victim's mouth, air flows OUT by itself. Why does this happen?  
I would appreciate your help,
Thanks
Jazira

Answer
Hi Jazira:  Thanks for your question.

One important thing to remember is that the relaxed state of the lungs is in the expired air position.  This means that when you inhale, the muscles of the ribs (intercostals) contract and expand the lungs.  The diaphragm also contracts, moving down.  Both these actions serve to increase the space in the lungs thereby drawing air into the lungs.  When these sets of muscles relax, then air is forced out of the lungs.

So when the rescuer breathes air into the victim's lungs, they expand.  But when the rescuer ceases inflating the lungs, the muscles relax, thereby forcing air out of the lungs.

Here's a website that may help.

http://en.wikipedia.org/wiki/Artificial_respiration

Hope this helps!

FM Rollwagen. PhD

Biology

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Florence M Rollwagen

Expertise

I can answer questions in biology, microbiology and immunology on the undergraduate or graduate level. I can also address medical and health concerns regarding alternative medicine, autoimmune diseases (lupus, MS) liver disease and intestinal problems.

Experience

I have over 20 years experience in research and teaching at the medical/graduate level, and 5 years teaching college biology and microbiology. My expertise is in microbiology and immunology, specifically the biology of cytokines and soluble immune response modifiers. I also carried out original research in blood substitutes and shock/trauma.

Organizations
American Association of Immunologists (AAI) American Association for the Advancement of Science (AAAS)

Publications
Journal of Experimental Medicine, Journal of Immunology, Cytokine, Shock, Experimental Hematology

Education/Credentials
BS biology 1966 MS biology 1968 PhD immunology 1979

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