How our Lungs Work
Our lungs are responsible for providing our body with oxygen and expelling the carbon dioxide that's left over once our body has used the oxygen. The lungs do this through a series of clusters of small air sacs called, alveoli. These clusters are separated by a very thin membrane that allows the exchange of oxygen and carbon dioxide through the tiny blood vessels that travel through the membrane.
Air enters the alveoli through the the "bronchial tree. The trachea splits into the right and left mainstem bronchi, which branch further into bronchioles and finally ends in the alveolar air sacs" (www.medicinenet.com). As we breathe in, the alveoli expand, and the oxygen is transferraed to the hemoglobin in the red blood cells to be distributed to the rest of the body. During this transfer, carbon dioxide transfers from the bloodstream to the alveoli to be expelled.
What is Emphysema?
Emphysema is the name given to the condition where the alveolar walls have been destroyed along with the tiny (capillary) blood vessels that run within them. The loss of these membranes means that there is less total area in the lungs for the oxygen/carbon dioxide exchange to happen. In some cases, there is only inflammation of the bronchioles (airways) which limits the amount of air traveling through the alveoli. In severe cases, the bronchioles and alveoli collapse making it hard to expel and take in air.
With the oxygen intake of the body impaired, oxygen concentrations in the bloodstream are also compromised which leads to an increased breathing rate. The heart has to work harder to push blood through blood vessels which have narrowed due to lack of oxygen resulting in pulmonary hypertension - the increase of blood pressure within the lungs. Over time, this can lead to heart failure.
Emphysema is considered part of the group of diseases called chronic obstructive pulmonary disease (COPD). It is a chronic condition that worsens over time.
- One in every 135 Canadians has emphysema
- Over 2 million Americans have emphysema