Emphysema develops when many of the small air sacs or alveoli in the lungs get stretched out and lose their ability to empty out all of the air. Air becomes trapped in the alveoli and the alveoli become stretched out and over-inflated.
This damage can cause the alveoli to come apart (rupture), and form one large air space instead of many small ones. The destruction of healthy air sacs makes it difficult for the lung to work properly.
There are less alveoli to deliver oxygen to the bloodstream. The damage is progressive and, as lung tissue does not repair itself, the damage is permanent. The whole body suffers when the lung cannot deliver the essential oxygen and remove the carbon dioxide waste.
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