The pathophysiology of COPD involves chronic inflammation of the lung tissue, which occurs when inflammatory cells, such as T-lymphocytes and neutrophils accumulate in the airways, according to About.com Health. This inflammation is a response to chronic exposure to irritants, such as cigarette smoke and other air pollutants.
When inflammatory cells are triggered, they release inflammatory mediators, which remove or destroy foreign debris. In COPD, repeated inflammatory response causes physiological and structural changes in the lung tissue, such as narrowing of the airways and excessive production of mucus. These changes worsen over time and cause COPD symptoms such as shortness of breath, dyspnea, coughing and wheezing. About.com Health notes that bacteria may also accumulate in the affected lung tissue, leading to a bacterial infection and more inflammation.