Asthma Flashcards
What is asthma?
Asthma is a chronic inflammatory condition of the airways characterised by reversible airway obstruction and hyperresponsiveness.
What are the common symptoms of asthma?
Symptoms include wheezing, shortness of breath, chest tightness, and cough, often worse at night or early morning.
What are the triggers for asthma?
Triggers include allergens (e.g., pollen, dust mites), respiratory infections, exercise, cold air, smoking, and stress.
What is the pathophysiology of asthma?
It involves airway inflammation, bronchoconstriction, and mucus hypersecretion, leading to reversible airway obstruction.
What are the risk factors for developing asthma?
Risk factors include a family history of asthma, atopy, exposure to tobacco smoke, and environmental allergens.
What is the role of atopy in asthma?
Atopy is a predisposition to develop allergic conditions such as asthma, eczema, and allergic rhinitis, often associated with raised IgE levels.
What are the common signs of asthma on clinical examination?
Signs include expiratory wheeze, tachypnoea, tachycardia, and in severe cases, reduced breath sounds or accessory muscle use.
How is asthma diagnosed?
Diagnosis is based on clinical history, spirometry showing reversible airflow obstruction, and positive bronchodilator or bronchoprovocation tests.
What spirometry findings are suggestive of asthma?
A reduced FEV1/FVC ratio (<70%) with an increase in FEV1 of at least 12% and 200 mL after bronchodilator use suggests asthma.
What is peak expiratory flow (PEF) testing in asthma?
PEF testing measures airway obstruction and variability, with diurnal variation >20% being suggestive of asthma.
What are the key features of mild asthma exacerbation?
Features include mild symptoms that are relieved by reliever inhalers with no significant impact on daily activities or sleep.
What are the features of a severe asthma exacerbation?
Features include inability to complete sentences, respiratory rate ≥25/min, heart rate ≥110 bpm, and PEF <50% of predicted.
What is life-threatening asthma?
Life-threatening asthma involves features such as silent chest, cyanosis, exhaustion, confusion, or a PEF <33% of predicted.
What investigations are used during an acute asthma exacerbation?
Investigations include oxygen saturation, arterial blood gas analysis, chest X-ray (to rule out complications), and blood tests (e.g., eosinophils).
What is the stepwise approach to asthma management?
It includes the use of short-acting beta-agonists (SABAs), inhaled corticosteroids (ICS), long-acting beta-agonists (LABAs), and leukotriene receptor antagonists (LTRAs).
