8.4 - Health Issues Related to the Human Respiratory System

**Chronic Obstructive Pulmonary Disease (COPD)**is a group of progressive lung diseases, characterized by airway blockage and breathing-related problems. The group of lung diseases includes emphysema, asthma and chronic bronchitis.

• Patients with emphysema will normally have shortness of breath. The alveoli in the lungs are damaged. Eventually, the inner walls of the alveoli weaken and rupture, creating large air spaces in the lung tissue.
• Asthmatic patients have swollen and thicker bronchiole walls in the lungs. As a result, the air passage becomes narrower over time which leads to breathing difficulties.
• People with chronic bronchitis have prolonged inflammation at the lining of the bronchial tubes. The inflamed condition leads to a build-up of mucus in the tubes, resulting in breathing difficulties. Constant and heavy coughing is one of the hallmarks seen in chronic bronchitis.

Figure 14 - Normal and healthy alveoli (left). Damaged alveoli with large air spaces (right) which can be seen in people with emphysema.

Figure 15 - Normal bronchiole (left) with normal air passage. In asthmatic patients, bronchiole walls are swollen and thicken which cause the airway to narrow (middle). In chronic bronchitis patients, inflamed bronchioles cause narrowing of the air passage. Mucus formed surrounds the airway leads to shortness of breath (right).