The formal diagnosis of COPD is made with breathing testing or what we call “pulmonary function testing”. This is a series of tests which measures how fast air flows through the bronchial tubes, how much air one exhales with a full and forced exhalation, and how fast that air is flowing is the most basic measurement. This test is done by what we call spyrometry. Simple spyrometry can be done in many or most primary care physicians’ offices.
As testing has become more sophisticated, and testing equipment, physiology testing is available in the office of a lung specialist, measurement can be done of the airflow in the smaller bronchial tubes, the very small bronchial tubes, measure how much air is left in the lung at the end of somebody’s most effective exhalation. When too much air is left in your lung, that’s called air trapping. It is believed that air trapping, or too much air in the lung because of the small bronchial tubes, influences your ability to breath comfortably and to exercise.
We measure how your oxygen is. If that is low at rest and/or with exercise and we can measure how gas gets from the air sack into the blood vessel, into the blood stream, which is really what your lung is all about. Your lung is there to get oxygen and carbon dioxide out, so depending on the situation and the patient and the clinical setting, there can be more or less testing done. But a screening test, that should be done really for every patient, it is believed as part of a well visit, especially patients who smoke, who have any other risk factors, patients with breathlessness, patients with cough. That can be done by a primary care physician and then referred to a pulmonary physician if need be, for further evaluation.
History, getting information from the patient, asking carefully about their breathing, querying carefully about coughing, about tendency to get chest colds, about wheezing, about why one can’t exercise as you think you should when you’re in the gym. Many people attribute it just to being de-conditioned and out of shape when, in fact, there is some lung disease present. So an index of suspicion is always very important.