Patients with COPD often describe fatigue as a feeling of general tiredness that occurs daily. Its occurrence may be intermittent throughout the day and constant during the evening, following a day of normal activities. It is also a result of the poor quality of sleep many patients experience, due to the nocturnal events (such as struggling to breathe) of COPD. Fatigue is generally described as constantly present during exacerbations.

Changes in lung tissue interfere with gas exchange in a progressive way until patients have low levels of oxygen and high levels of carbon dioxide in their blood. Lack of proper oxygenation in the blood can result in tissue hypoxemia (a lack of oxygen in the tissues), cyanosis (a bluish or purplish discoloration due to lack of oxygen) that may appear on the lips, and edema, often in the ankles or feet. Hypoxemia gives the tissues a bluish tone, and chronic edema produces a swollen appearance. Many of these patients have abnormalities of oxygenation that worsen during sleep because of upper airway obstruction and/or an altered breathing drive in the brainstem.

The terms “blue bloaters” and “pink puffers” may be used by physicians to describe patients with COPD. Because a lack of proper oxygenation of the blood can lead to cyanosis and edema, physicians may refer to patients with advanced bron­chitis as “blue bloaters.” Physicians may refer to other patients as “pink puffers.” These patients present with good color, but use the accessory muscles of the neck while breathing in, often through pursed lips.

Weight loss is associated with decreased lung function, as the body works harder and harder to breathe adequately. It is also indicative of the emphasis on COPD as a systemic disease – and not a disease solely associated with lung function. Weight loss in patients with COPD is due to increased metabolism and manifests itself as a loss of skeletal muscle and a wasting of limb muscle. Skeletal muscle weakness is common in patients with COPD, and exacerbates dyspnea. Weight loss alone is not a predictive factor, however, and may indicate carcinoma.

Wheezing is the descriptive term for the whistling sound that COPD patients can make on expiration, either at rest or when breathing is labored. As the disease progresses, wheezing becomes more prominent, and may be either constant or sporadic. Patients in the earlier stages of COPD may wheeze upon moderate to heavy exertion, or wheezing may accompany a cough. Patient-reported wheezing, however, has limited usefulness in diagnosing COPD. Rhonchi is the name for loud, rattling wheezes, often associated with very thick secretions and mucus in the central airways of patients with active chronic bronchitis or acute exacerbations of COPD.