Bronchial Asthma - S6 Medical Course

Bronchial Asthma Overview

• Bronchial asthma is a chronic inflammatory lung disease with significant respiratory symptoms, activity limitations, and potential for life-threatening flare-ups.
• Characterized by three primary airway issues: obstruction, inflammation, and hyperresponsiveness.

Definition and Etiology

• Asthma implies difficulty in breathing; main symptoms include dyspnea, cough, and wheezing.
• Risk factors include:
  • Activity: Exercise-induced asthma.
  • Diet: Allergens in eggs, fish, and milk.
  • Drugs: Reactions to aspirin and penicillin.
  • Family history: Correlation with urticaria and hay fever.
  • Inhalants: Tobacco smoke, dust, pollen, and molds.
  • Infections: Sources like tonsillitis and bronchitis.
  • Hormonal influences: Variations during pregnancy, menstruation, and menopause.

Genetic and Environmental Factors

• Genetic predisposition; the risk increases significantly if one or both parents have asthma.
• Atopic conditions are essential in asthma development, with environmental allergens provoking IgE antibody overproduction.
• Obesity and stress also contribute to the exacerbation of asthma symptoms.

Types and Phenotypes of Asthma

• Atopic Asthma: Most common variant, linked to allergies and high levels of IgE.
• Allergic Bronchopulmonary Mycosis (ABPM): Hypersensitivity to molds, especially Aspergillus fumigatus.
• Aspirin-sensitive Asthma (ASA): Onset typically in adulthood; severe reactions after NSAID use.

Pathogenesis and Clinical Features

• Triggers lead to inflammatory cell activation (mast cells, eosinophils, etc.) releasing mediators like histamine, causing bronchoconstriction and airway hyperresponsiveness.
• Clinical signs include:
  • General signs: Tachypnea, tachycardia, prolonged expiration.
  • Local signs: Hyperinflation, use of accessory muscles, wheezing, diminished breath sounds.

Diagnostic Investigations

• Chest X-ray, sputum analysis, blood tests, allergy tests, ECG, pulmonary function tests (PFT), bronchial provocation tests, and exercise testing.

Complications of Asthma

• Severe complications can include status asthmaticus, COPD development, respiratory failure, cor pulmonale, pneumothorax, and allergic aspergillosis.

Acute Severe Asthma (Status Asthmaticus)

• A progressive, severe asthma attack persisting for more than 6 hours, requiring immediate intervention.
• Symptoms include tachypnea, cyanosis, and potential vascular collapse.

Management Strategies

• Therapeutic: Inhaled bronchodilators (short and long-acting), anti-inflammatory drugs (corticosteroids, leukotriene inhibitors), and antihistamines.
• Long-term management: Avoidance of triggers and adherence to inhaler therapy.

Stepwise Treatment Approach

• Step 1: Intermittent treatment with short-acting B2 agonists.
• Step 2: Adding inhaled corticosteroids for mild asthma.
• Step 3: Combination therapy for moderate cases.
• Step 4: Intensive management for severe asthma.

Emergency Care for Acute Exacerbation

• Indications for ICU transfer include PaCO2 > 40 mmHg or PEF < 25% of baseline.
• ICU treatment involves frequent nebulization of B2 agonists, intravenous hydration, and potential intubation if necessary.

Contact Information

• Ass. Prof. Ragia Sharshar, Faculty of Medicine, Tanta University.
• Email: [email protected]

This quiz covers key concepts and principles related to bronchial asthma as part of the Respiratory course in the Competency-based Medical Bachelor Program. Learn about the pathophysiology, diagnosis, and management of this common respiratory condition. Test your knowledge and prepare effectively for your upcoming assessments.