Chronic bronchitis is defined clinically as a productive cough that persists for periods of up to three months and occurs one or more times a year for at least two years. During these periods, the risk of infection, including pneumonia, is high. The inflammation of the bronchial passages and increased mucus production that characterize these periods are uncomfortable: Patients report wheezing, difficulty breathing and feeling as though they cannot get enough air.
For divers, the inflammation and excess mucus lead to the possibility of trapping dense compressed gas at depth. Upon ascent the gas will expand in volume, potentially leading to pulmonary barotrauma, which could include pneumothorax (collapsed lung) and, in the worst case, arterial gas embolism (AGE). Of these, AGE is the most immediate threat to life, but a complicated pneumothorax can also be fatal.
Emphysema is defined clinically as permanent abnormal enlargement of the air spaces within the lungs due to the deterioration of the alveoli. These enlarged spaces are conducive to trapping air at depth, which creates the same possibility of pulmonary barotrauma as chronic bronchitis.
For medical management purposes with regard to medications and other therapies, physicians classify COPD as mild, moderate, severe or very severe, as determined by severity of airflow obstruction. Even with the clinical designation of mild there is measurable obstruction beyond what is considered safe among pulmonology experts trained in dive medicine. For these reasons, diving with COPD — even mild COPD — is not recommended.
THANKS FOR THE INFORMATION AND FOR ANSWERING MY QUESTION, I HAVE SEVERE EMPHYSEMA AND CHRONIC BRONCHITIS AND COPD PLUS CONGESTIVE HEART FAILURE I'M 58 YEARS OLD I HAD BEEN WONDERING IF YOU COULD SCUBA DIVE HAVING A LUNG CONDITION LIKE MINE, NOW I KNOW THAT YOU CANNOT AND ARE PLAYING A GAME WITH YOUR LIFE IF YOU TRIED IT. THANK YOU ALL. MIKE HARTSOOK JOHNSON CITY TENNESSEE USA.