Common Respiratory Disorders

- Respiratory disorders encompass a wide range of conditions affecting the organs and structures involved in breathing and gas exchange.

- These disorders can result from infections, allergies, environmental factors, genetic predisposition, and lifestyle choices.

1. Asthma

Definition:   Chronic inflammatory disorder of the airways characterized by recurrent episodes of wheezing, breathlessness, chest tightness, and coughing.

Pathophysiology:  

  - Airway inflammation leads to bronchoconstriction, narrowing of the airways, and increased mucus production, causing airflow obstruction.

  - Triggers include allergens, respiratory infections, exercise, cold air, and stress.

Management:  

  - Short-acting bronchodilators (e.g., albuterol) for acute relief of symptoms.

  - Inhaled corticosteroids and long-acting bronchodilators for long-term control of inflammation and symptoms.

  - Avoidance of triggers and use of peak flow meters to monitor lung function.

2. Chronic Obstructive Pulmonary Disease (COPD)

Definition:   Progressive lung diseases, including chronic bronchitis and emphysema, characterized by airflow limitation and breathing difficulties.

Pathophysiology:  

  - Chronic inflammation and narrowing of the airways (chronic bronchitis).

  - Destruction of alveolar walls and loss of lung elasticity (emphysema).

  - Main risk factor: Smoking, although exposure to air pollutants and genetic factors also play a role.

Management:  

  - Smoking cessation is essential to slow disease progression.

  - Bronchodilators (short-acting and long-acting) and inhaled corticosteroids to relieve symptoms and reduce exacerbations.

  - Pulmonary rehabilitation, oxygen therapy, and vaccination against respiratory infections.

3. Pneumonia

Definition:   Infection of the lung parenchyma, often caused by bacteria, viruses, fungi, or parasites.

Pathophysiology:  

  - Inflammatory response leads to alveolar consolidation, edema, and exudate formation.

  - Symptoms include fever, cough, chest pain, shortness of breath, and sputum production.

Management:  

  - Antibiotics for bacterial pneumonia (guided by culture and sensitivity testing).

  - Antiviral medications for viral pneumonia (e.g., oseltamivir for influenza).

  - Supportive care, including rest, fluids, and fever control.

4. Influenza (Flu)

Definition:   Viral infection of the respiratory system caused by influenza viruses (types A, B, and rarely C).

Pathophysiology:  

  - Highly contagious virus transmitted via respiratory droplets.

  - Symptoms include sudden onset of fever, chills, sore throat, cough, muscle aches, and fatigue.

Management:  

  - Antiviral medications (e.g., oseltamivir, zanamivir) if started early in the course of illness to reduce severity and duration.

  - Supportive care, including rest, fluids, and fever control.

  - Annual influenza vaccination to prevent infection and reduce transmission.

5. Tuberculosis (TB)

Definition:   Infectious disease caused by Mycobacterium tuberculosis, usually affecting the lungs (pulmonary TB) but can involve other organs (extrapulmonary TB).

Pathophysiology:  

  - Spread via airborne droplets from coughing or sneezing by individuals with active TB.

  - Primary TB infection occurs when the bacteria are inhaled, leading to formation of granulomas (tubercles) in the lungs.

  - Reactivation TB may occur years later if the immune system weakens.

Management:  

  - Antibiotic therapy with multiple drugs (e.g., rifampin, isoniazid, pyrazinamide, ethambutol) for several months to eradicate the bacteria.

  - Directly Observed Therapy (DOT) to ensure adherence to treatment.

  - Infection control measures to prevent transmission, including isolation of contagious individuals and contact tracing.