Exhalation

Exhalation or exhalation is when the air leaves the lungs or the phenomenon opposite to the inhalation, during which the air that is in the lungs leaves of these. It is a passive phase of breathing, because the chest is removed and all diameters decrease, without intervention of the muscular contraction, returning to recover the thorax its previous form. The muscles in play, when dilating the thorax, relax in this phase; The ribs return to their initial position as well as the diaphragm. Expiration is considered as a passive phenomenon, and yet it is also partly active, as was inspiration, since some muscles such as the internal intercostals intervene in this act, to which must be added the abdominal muscles in the forced expiration and the wide dorsal in the accesses of cough.

In exhalation the air exits quickly, which facilitates the expulsion of mucus and foreign particles that could obstruct the airways. Notes

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