Physiology
This is the hallmark physiological abnormality in COPD, caused by airway narrowing, airway obstruction, and reduced elastic recoil.
What is persistent airflow limitation?
The two major structural disease processes that together make up most COPD are chronic bronchitis and this other condition.
What is emphysema?
This is the leading cause and most important risk factor for COPD.
What is cigarette smoking?
This symptom develops because hyperinflation, increased work of breathing, and impaired gas exchange make breathing feel difficult.
What is dyspnea
Patients with COPD usually have more difficulty with this phase of breathing than with inspiration.
What is expiration?
In emphysema, destruction of alveolar walls reduces the surface area for this essential gas-exchange process.
What is diffusion of oxygen and carbon dioxide across the alveolar-capillary membrane?
Besides cigarette smoking, long-term exposure to these workplace and environmental inhalants can also cause COPD.
What are dusts, chemical fumes, air pollution, biomass smoke, and secondhand smoke?
During flare-ups of COPD, these common triggers often worsen airway inflammation and obstruction.
What are respiratory infections and inhaled irritants such as poor air quality, cold air, or fumes?
This phenomenon happens when air cannot be fully exhaled before the next breath begins, increasing end-expiratory lung volume.
What is air trapping
This pathophysiological mismatch occurs in COPD because some alveoli are poorly ventilated relative to their blood flow.
What is ventilation-perfusion (V/Q) mismatch?
This inherited condition is a classic genetic risk factor for COPD, especially early-onset emphysema.
What is alpha-1 antitrypsin deficiency?
As COPD becomes severe, patients may develop this blood-gas abnormality because they cannot adequately remove carbon dioxide.
What is hypercapnia?