Respiratory disorders are medical conditions that affect the organs of the respiratory system, such as the nasal passage, bronchi, lungs, and alveoli.
They can result from infections, allergies, pollution, occupational exposure, or genetic factors.
These disorders interfere with respiration, leading to reduced oxygen supply and accumulation of carbon dioxide in the body.
Respiratory disorders are classified based on the affected region or cause:
Asthma is a chronic inflammatory disorder of the airways characterized by reversible narrowing of bronchi and bronchioles.
Cause:
Allergic reactions due to pollen, dust, cold air, or pollutants trigger inflammation and mucus secretion.
Symptoms:
Mechanism:
The bronchial smooth muscles constrict, and mucus production increases, obstructing airflow during exhalation.
Emphysema is a chronic obstructive pulmonary disease (COPD) where the alveolar walls are destroyed, reducing the surface area for gas exchange.
Cause:
Long-term smoking, air pollution, or exposure to harmful gases.
Symptoms:
Biological Effect:
Loss of elasticity in alveoli prevents proper exhalation, leading to carbon dioxide retention.
Chronic bronchitis is an inflammation of the bronchi leading to excessive mucus production and airway obstruction.
Cause:
Prolonged exposure to smoke, industrial dust, or air pollutants.
Symptoms:
Pathophysiology:
The inner lining of bronchi thickens, and mucus accumulation blocks airflow, causing difficulty in breathing.
Pneumonia is an infection of the alveoli, usually caused by bacteria (Streptococcus pneumoniae) or viruses.
Cause:
Inhalation of infectious droplets or weakened immunity.
Symptoms:
Effect:
The alveoli fill with fluid and pus, reducing oxygen absorption and resulting in breathing difficulty.
These disorders develop from prolonged inhalation of dust and chemical particles in industrial environments.
Examples:
Symptoms:
Impact:
Causes fibrosis (hardening) of lung tissue, reducing lung elasticity and gas exchange efficiency.
Lung cancer is caused by uncontrolled growth of abnormal cells in lung tissue.
Cause:
Cigarette smoking, asbestos exposure, genetic mutations.
Symptoms:
Pathogenesis:
Carcinogenic substances trigger mutations that cause abnormal cell proliferation, leading to tumor formation.
Respiratory diseases interfere with one or more steps of respiration:
The overall result is hypoxia (low oxygen) and hypercapnia (excess carbon dioxide), leading to fatigue, respiratory distress, or even failure.
Early detection and lifestyle modification can significantly reduce the risk of severe respiratory damage.
(Session 2026 - 27)