Why does a copd patient have a prolonged exhalation time?

Narrowed Plumming: Through means we do not completely understand, people with COPD have narrowing of the tubes that deliver air to sacs in the lung where oxygen is absorbed. This is probably due to prolonged exposure to irritants that damage the tissue. The pressure from breathing out can further compress the tubes. The smaller the tube the longer it takes the air to pass.

Lung structuring: As the condition advances, the lungs themselves may change and lose their elasticity. and other structural changes. If this is a problem, you may want to discuss lung rehabilitation with your physician. This may help. Good Luck