Question:
I have a friend who has more than 400 dives but might have COPD (Chronic Obstructive Pulmonary Disease). Will this affect his diving?

Answer:
COPD describes several lung problems, but the most common form of COPD is pulmonary emphysema caused by cigarette smoking. As a Navy diving medical officer, I counseled many divers on the enormous benefits of quitting smoking.

While I concede that the addictive properties of nicotine are well known, there are many new medications and quitting strategies available to motivated individuals. So what about COPD and diving?

Emphysema is caused by destruction of elastic tissue within the lungs, creating air sacs that can no longer completely empty when the diver exhales. Not only does this impair gas exchange, but it also creates areas of the lung that can trap air and predispose the diver to a pulmonary overexpansion injury (e.g., pneumothorax, air embolism).

Making matters worse are the increased secretions and mucous plugging of airways that also result from smoking. The benefits of quitting smoking are nearly immediate, and can be directly applied to safer diving.