Signs and Symptoms

Many of the signs of COPD are caused by the body's attempt to compensate for a damaged respiratory system. Symptoms develop as a direct result of disease processes.

Signs
Signs of COPD are consequences of the anatomical changes caused by the disease: barrel chest, pursed-lip breathing, productive cough, and cyanosis.

Barrel Chest
One telling sign is the change in the shape of the chest, known as barrel chest. When the lungs become enlarged, the diaphragm is displaced downward and is unable to contract efficiently. Furthermore, the chest wall is enlarged, making accessory breathing muscles (muscles in the neck, upper chest, and between the ribs) less efficient as well. These changes contribute to shortness of breath. This becomes apparent when a person with COPD tries do something with the arms raised above the head, such as changing a light bulb in a ceiling fixture, and becomes short of breath.

To compensate, a person with COPD often sits leaning forward with their arms supported on a surface in front of them or on their knees. This stabilizes the upper chest and shoulders and allows them to use accessory respiratory muscles more efficiently.

Pursed-Lip Breathing
Because airflow out of the lungs becomes limited, exhalation takes longer. Because the alveoli lose their elasticity, one tries to shorten the time needed for exhalation by forcefully exhaling. Unfortunately, forced exhalation increases pressure on the lungs and causes structurally weakened airways to collapse. To prevent airways from closing during forced exhalation, pursed-lip breathing is used: The lips are narrowed together, which slows exhalation at the mouth. This keeps positive pressure in the airways, thus preventing their collapse and allowing some forced exhalation.

Productive Cough
A productive cough is caused by inflammation and excessive amounts of mucus in the airways. Coughing becomes less effective because of obstructed airflow.

Cyanosis
People who have a poor supply of oxygen usually have a bluish tinge to their skin, lips, and nailbeds, called cyanosis.

Symptoms

Shortness of Breath (dyspnea)
Dyspnea, the most common symptom of COPD, comes on gradually and is first noticed during physical exertion or during acute exacerbations. It usually begins when patients are in their 60s and 70s and slowly becomes more prominent. It is closely associated with lung function decline and is not always associated with low oxygen in the blood.

Patients often wonder why dyspnea occurs so long after beginning to smoke, say 50 to 60 years later. Some patients have even quit smoking several years before symptoms appear. The main reason is that lung function declines slowly with age, even in a nonsmoker. At approximately age 30, people begin to lose lung function at a rate of 25 to 30 mL/year of forced expiratory volume in 1 second (FEV1; see Spirometry). People who smoke lose lung function at a more rapid rate, approximately 125 mL/year. Because the lungs have a considerable amount of reserve, a large portion must become nonfunctional before symptoms occur. It can take more than 30 years to lose enough lung function to experience symptoms.

When a person quits smoking, the loss in function slows to approximately the rate of a nonsmoker. If smoking has already destroyed a large portion of the lungs, the threshold will be reached, eventually, at a rate of decline of 30 mL/year instead of 125 mL/year. Without quitting, decline would continue at a rate of 125 mL/year. Quality of life can improve by quitting, even if lung function has already declined.

Chronic Cough
Chronic cough typically begins as a morning cough and slowly progresses to an all-day cough. The cough usually produces small amounts of sputum (less than 60 mL/day) and is clear or whitish but may be discolored. Sputum production decreases when one quits smoking.