Bronchial Asthma: Definition and Pathophysiology

Study Notes

Definition and Epidemiology

Bronchial asthma is a chronic inflammatory disorder of the airways.
Characterized by recurring episodes of wheezing, breathlessness, chest tightness, and coughing, particularly at night or in the early morning.
It's a common respiratory disease affecting people of all ages globally.
Prevalence varies significantly across different populations and geographical regions.

Pathophysiology

The underlying inflammatory process involves immune cells and mediators, leading to airway hyperresponsiveness.
Exposure to certain triggers (allergens, irritants, exercise, etc.) leads to activation of the immune system and release of inflammatory mediators.
This process results in airway narrowing, mucus production, and edema, contributing to the symptoms of asthma.
Airway remodeling is a long-term consequence of chronic inflammation, leading to structural changes in the airways.

Triggers

Allergens: Dust mites, pollen, pet dander, mold, cockroaches, and food.
Irritants: Smoke, strong odors, chemical fumes, air pollution, and cold air.
Infections: Respiratory viral infections can trigger or exacerbate asthma attacks.
Exercise: Physical activity can induce bronchospasm in some individuals.
Medications: Certain medications (e.g., aspirin, beta-blockers) can trigger asthma attacks in susceptible individuals.
Stress and emotions: Emotional stress can trigger or worsen asthma symptoms.

Diagnosis

Diagnosis relies on a combination of patient history, physical examination, and lung function tests (e.g., spirometry).
Spirometry measures the airflow in the lungs, identifying airflow limitation, typical of asthma.
Peak expiratory flow rate (PEFR) monitoring can be used to assess symptom variability and response to treatment.
Allergen testing may be used to identify specific allergies contributing to asthma.
Bronchoprovocation testing can be used to demonstrate airway hyperresponsiveness.
Chest X-rays or CT scans may be helpful to rule out other lung diseases.

Classification

Asthma is categorized based on severity, symptom frequency, and response to treatment.
Different classifications exist, with varying criteria to define different levels of severity.
Severity is important for appropriate management and treatment strategies.

Treatment

Inhaled corticosteroids: These are the most commonly prescribed medications for long-term control of asthma.
Long-acting beta2-agonists: These medications help relax the airways and improve airflow.
Leukotriene modifiers: These medications block certain inflammatory mediators.
Bronchodilators: These rapidly relieve symptoms during an acute attack and improve airflow.
Immunotherapy (allergy shots): Useful for allergen-induced asthma to reduce sensitivity.
Avoidance of triggers: Recognizing and avoiding triggers can significantly reduce exacerbations (e.g., keeping pets out of bedroom).
Asthma action plans: Customized plans that guide daily management to help patients cope with flare-ups.

Management and Prevention

Lifestyle modifications to minimize exposure to triggers.
Regular monitoring of lung function.
Adherence to prescribed medications.
Vaccination against respiratory infections.
Early intervention and close monitoring for children with asthma.
Patient education plays a crucial role in asthma management.
Public health measures to reduce exposure to environmental factors that trigger or worsen asthma.

Complications

Frequent exacerbations can lead to irreversible airway damage (airway remodeling).
Uncontrolled asthma may result in significant morbidity and mortality, increasing the risk of hospitalization and emergency department visits.
Increased risk of other respiratory infections.
Poor quality of life due to persistent symptoms and limitations in physical activity.

Acute Exacerbation

Assessment and intervention are needed during acute exacerbations.
Rapid treatment and diagnosis are critical.
Treatment involves increasing the dose of bronchodilators, corticosteroids, possibly other medications.
Emergency medical attention should be sought if symptoms worsen rapidly.

Description

This quiz covers the definition, epidemiology, and pathophysiology of bronchial asthma. Learn about the chronic inflammatory disorder, its triggers, and how it affects individuals globally. Test your knowledge on the mechanisms that lead to asthma symptoms and airway remodeling.