COPD: Pathophysiology and Diagnosis

Developed and produced for http://www.MDPracticeGuide.com, a CME resource for physicians and healthcare providers.

Animation Description: Cigarette smoking is by far the most common primary risk factor of COPD worldwide.

According to global statistics, approximately 210 million people have COPD.

By 2030, COPD is predicted to be the fourth leading cause of death worldwide.

Epithelial cells lining the airways will respond to smoke inhalation by undergoing cellular changes due to long-term exposure.

Over time, chronic irritation and inflammation of the air passages causes small airways disease and parenchymal destruction.

Irritation and inflammation of the air passages causes constriction in the bronchi and bronchioles of the lung.

In a healthy individual, standing at rest at the foot of a staircase while breathing normally, lung volume is well balanced in terms of:
- IRV (Inspirational Reserve Volume);
- VT (Tidal Volume);
- FRC (Functional Residual Capacity).

In the severe COPD patient, lung function is extremely imbalanced with only a tiny capacity for IRV. A patient with severe COPD has a very difficult time managing everyday tasks such as stair climbing.

(Spirometry test) The patient is asked to inhale and then forcefully exhale until the lungs are completely emptied via a tube attached to a recording device.

The most important values from the spirometry readings are FEV1 and FVC.

If the ratio of these values is less than 0.7 then COPD is suspected. More detailed results from spirometry can reveal the stage of COPD in the patient.