COPD or Chronic Obstructive Pulmonary Disease is a disease that is characterized by what we call air flow limitation. Air flow limitation means the air flow through the bronchial tubes is less than it should be. The limitation of flow of air is not reversible. That means that if you give certain medications which would make this flow normal again in somebody with asthma, that even with those medications such as inhalers that people use, that you cannot get it to correct.
I think its important getting started to have a visual image of the lung in terms of its being divided into bronchial tubes and the lung tissue itself. The lung is like a tree; the tree trunk would be your windpipe, the air sacks where oxygen gets into the bloodstream, which is what your lung is about, are the leaves and the fruit all the way at the end of the many many many many branches. We think of the bronchial tubes as being all those branches that are dividing and dividing and dividing and dividing. So if the branches are narrowed, they don’t let the air out toward the edge of the lung. That’s obstructive lung disease or obstructive airways disease.
We think of COPD or chronic obstructive pulmonary disease or chronic obstructive lung disease as a condition that has many different parts to it. It can present in many different ways in different people. And importantly we’ve learned recently that it has effects in other parts of the body and can be connected with and associated with other illnesses as well.