Chronic obstructive pulmonary disease (COPD) refers to a type of obstructive lung disease that is characterized by difficulties in long-term breathing and airflow issues. Common symptoms of the disease include limitations in breathing, wheezing, cough, as well as sputum production. The most widespread cause of COPD’s development is the exposure of an individual to particulate matter or irritating gases, most often from cigarette smoke. The severity of COPD increases with the occurrence of chronic bronchitis and emphysema.
The lungs contain more than 300 million small air sacs, alveoli, which, in a healthy state, are stretchy and expand during inhalation. Breathing out, therefore, does not take much effort as the alveoli can get back into their original size. However, with COPD, the walls of the alveoli become severely damaged and are not as flexible as they are in a healthy state. This means that the alveoli cannot empty easily, leading to complications in exhaling.
Individuals diagnosed with obstructive pulmonary disease have shortness of breath because of the difficulty exhaling all from the lungs and not inhaling. This is associated with the increased damage to the lungs as well as the narrowing of the airways inside the lungs. This contributes to the slowing down of the air that is being exhaled from the lungs. At the end of a full exhalation of air, the lungs may still contain high amounts of exhaled air, which is often referred to as ‘air trapping.’ The inability to fully exhale leads to an increased expansion (hyperinflation) of the lungs. The long-term build-up of air in the lungs combined with the continuous extra effort needed to breathe results in an individual experiencing constant shortness of breath.