There are many ways in which cancer can cause fatigue. The growth of a tumor, in general, can be taxing for your body. Other symptoms of cancer such as shortness of breath, anemia, pain, or a decreased level of oxygen in your blood (hypoxia) can cause fatigue.
A pulmonary function test may take 30 to 60 minutes to complete. This will vary according to the amount of trials necessary for you to get repeatable test results.
1 Just Breathe: Studies in Pulmonary Function The lungs move oxygen into the body and carbon dioxide out into the air. 2  Pulmonary function studies are conducted to measure the effectiveness of your lung function.3  Here is â¦. The primary causeâ¦. 2  Just Breathe: Studies in Pulmonary Function The lungs move oxygen into the body and carbon dioxide out into the air. 3  Pulmonary function studies are conducted to measure the effectiveness of your lung function. 4  Here is â¦.