Time-Line for Tobacco-Related Diseases
Conclusion: The smoke-damaged lung has the capacity to work normally for a long time before symptoms occur. This delayed onset of symptoms catches the smoker by surprise at a time when the process is irreversible.
Chronic Obstructive Pulmonary Disease
Introduction: Emphysema (alveolar disease) and chronic bronchitis (airway disease) are different diseases. Pure forms exist, but patients often have some combination of both diseases. Both are included in the term chronic obstructive pulmonary disease. Here, some of the features of each disease will be described, beginning with a case history of a patient with symptoms of both emphysema and chronic bronchitis.
Clinical summary: A 65-year-old man was admitted to the hospital for severe difficulty breathing. A 50-pack-year* smoker, he had a long history of emphysema, for which he was being treated with corticosteroids (anti-inflammatory and immunosuppressive medicine) and supplemental oxygen. There was a history of cough with phlegm that was troublesome especially during the winter months. Every year he usually had several colds that seemed to last a long time. He often noted wheezing. For the last few years, he required supplemental oxygen because he was short of breath on walking up one flight of steps or even walking one block on level ground.
Physical examination showed a wasted man with noisy breath sounds and a prolonged expiratory phase with a wheeze. The skin was slightly blue (not enough oxygen). A breathing tube was inserted into his trachea to deliver oxygen. The airways had mucous plugs that had to be removed. After several days, his oxygenation improved, the tube was removed, and he was able to be discharged to a nursing home.
Pulmonary function tests at a time when he was stable indicated the following:
Interpretation of function tests: The ability to blow out only 0.9 L on maximal exertion indicates severe airflow obstruction and trapping of air in the lungs. The ratio of FEV1/FVC is another measure of the same airflow obstruction indicating airway disease. The low blood oxygen tension indicates that the lungs have failed to provide normal gas exchange indicating alveolar disease.
*He smoked 1 pack a day for 50 years.
Comment: Emphysema is a chronic, gradually progressive disease that limits activity and makes the person susceptible to infections. Symptoms begin years after a person begins to smoke. Treatment options are limited.