RESP Flashcards
What is the definition of asthma?
Chronic inflammatory condition of the lungs characterized by reversible airway obstruction, hyperresponsiveness, and inflammation.
What are the types of asthma?
- Extrinsic (Atopic, Allergic): Triggered by allergens like dust, pollen, or animal dander.
- Intrinsic (Non-Atopic): Not allergy-related; often starts in adulthood and triggered by respiratory infections or irritants.
What are the causes of airway narrowing in asthma?
- Smooth muscle contraction.
- Thickened airway walls from inflammation and swelling.
- Increased mucus production clogging the airways.
What cells and mediators are involved in asthma?
- Dendritic cells.
- Th2 lymphocytes.
- Eosinophils.
- Mast cells.
- Cytokines (e.g., IL-4, IL-5), histamine, and leukotrienes.
What are common triggers of asthma?
- Allergens: Dust, pollen, mold, animal dander.
- Irritants: Tobacco smoke, air pollution, strong odors.
- Other triggers: Cold air, exercise, viral infections, medications (e.g., NSAIDs, beta-blockers).
What are the symptoms and signs of asthma?
- Symptoms: Intermittent shortness of breath (SOB), wheezing, chest tightness, and cough.
- Worse at night or early morning.
- Triggered by allergens, exercise, or infections.
- Signs: Bilateral wheezing (expiratory > inspiratory), prolonged expiration time, use of accessory muscles during breathing, cyanosis or ‘silent chest’ in severe cases.
How is asthma diagnosed?
- Pulmonary Function Tests (PFTs): Show reversible airway obstruction (FEV1 increase ≥12% and 200 mL after bronchodilator).
- Peak Expiratory Flow Rate (PEFR): Useful for monitoring, especially during exacerbations.
- Methacholine Challenge Test: For normal PFTs but high suspicion.
- Skin Prick Test: Identifies allergic causes.
- ABG: Assesses severity (mild hyperventilation to respiratory failure).
What are the ABG findings in asthma exacerbations?
- Mild: Low CO2, high pH (hyperventilation).
- Moderate: Normal CO2 and pH.
- Severe: High CO2, low pH (respiratory acidosis).
What is the stepwise treatment of asthma according to GINA guidelines?
- Step 1: Low-dose ICS-formoterol(LABA) as needed or SABA + low does ICS
- Step 2: Daily low-dose ICS or as-needed ICS-formoterol.
- Step 3: Daily ICS-LABA or ICS-LTRA
- Step 4: Medium-dose ICS-LABA (consider adding tiotropium or LTRA).
- Step 5: High-dose ICS-LABA, add low-dose oral steroids if needed.
How is acute asthma exacerbation managed?
- Oxygen therapy: Maintain SpO2 ≥94%.
- Bronchodilators: Nebulized salbutamol (SABA) and ipratropium bromide.
- Corticosteroids: Oral prednisolone or IV hydrocortisone.
- Magnesium sulfate: IV for severe cases.
- Mechanical ventilation: For respiratory failure (silent chest, cyanosis, exhaustion).
What are signs of poor asthma control?
- Frequent symptoms (>2 days/week).
- Nighttime awakenings.
- Increased reliever use.
- Activity limitation.
What is the difference between asthma and COPD?
- Asthma: Reversible airway obstruction, typically in younger individuals, often allergy-associated.
- COPD: Irreversible obstruction, common in older adults with a smoking history.
What is COPD?
Chronic disease characterized by irreversible airflow limitation, caused by damage to the lungs and airways, typically due to smoking or other irritants.
What are the common causes and risk factors for COPD?
- Causes: Chronic exposure to harmful particles or gases (e.g., smoking, air pollution).
- Risk factors: Smoking (primary cause), long-term exposure to biomass fuels, occupational dusts and chemicals, genetic factors: Alpha-1 antitrypsin deficiency.
What are the symptoms of COPD?
- Chronic cough, usually productive.
- Progressive shortness of breath, especially with exertion.
- Wheezing and chest tightness.
- Frequent respiratory infections.
- Fatigue and unintended weight loss in severe cases.
What are the two main types of COPD?
- Chronic Bronchitis: Defined as chronic productive cough lasting at least 3 months for 2 consecutive years, involves inflammation and increased mucus production in the airways.
- Emphysema: Characterized by destruction of alveolar walls and loss of lung elasticity, leads to hyperinflation, air trapping, and reduced gas exchange.
What are the signs of COPD on physical examination?
- Barrel-shaped chest (hyperinflation).
- Prolonged expiratory phase.
- Use of accessory muscles for breathing.
- Reduced breath sounds and wheezing.
- Cyanosis and signs of right heart failure in advanced cases.
How is COPD diagnosed?
- Spirometry: Post-bronchodilator FEV1/FVC ratio <70% confirms airflow limitation.
- Chest X-ray: Hyperinflated lungs, flattened diaphragm, and increased retrosternal air space.
- ABG: Hypoxemia and hypercapnia in advanced disease.
- CT scan: For detailed imaging in severe cases or suspected complications.
What is the GOLD classification of COPD severity?
- GOLD 1: Mild (≥80% predicted).
- GOLD 2: Moderate (50-79% predicted).
- GOLD 3: Severe (30-49% predicted).
- GOLD 4: Very severe (<30% predicted).
How is stable COPD managed?
- Non-Pharmacological: Smoking cessation (most important intervention), pulmonary rehabilitation (exercise training, education), vaccinations (influenza and pneumococcal vaccines).
- Pharmacological: Bronchodilators: Long-acting (LAMA, LABA) are first-line, inhaled corticosteroids (ICS) for frequent exacerbators (eosinophilic phenotype), combined LAMA+LABA or LABA+ICS for moderate to severe COPD, mucolytics for chronic sputum production.
How is an acute exacerbation of COPD managed?
- Controlled oxygen therapy: Keep SpO2 between 88-92%.
- Bronchodilators: Nebulized salbutamol (SABA) and ipratropium bromide (LAMA).
- Systemic corticosteroids: Prednisolone (oral) or IV methylprednisolone.
- Antibiotics: For bacterial infections (e.g., amoxicillin, doxycycline).
- LMWH for DVT prophylaxis
- Non-invasive ventilation (NIV): For hypercapnic respiratory failure.
- Hospitalization: For severe cases or significant comorbidities.
What are complications of COPD?
- Respiratory failure.
- acute exacerbation (infection, noncompliance, cardiac problems).
- Pulmonary hypertension and cor pulmonale (right-sided heart failure).
- Secondary polycythemia (increased red blood cells).
How is end-stage COPD managed?
- Long-term oxygen therapy (LTOT) for patients with chronic hypoxemia.
- Palliative care to address symptoms and improve quality of life.
- Smoking cessation and supportive care remain key.
What is bronchiectasis?
A condition where the bronchi are permanently widened due to chronic infection and inflammation, leading to mucus buildup and recurrent infections.