Asthma

Question 0

Describe in outline, the pathophysiology of asthma

Answer 0

Healthy lung –> asthmatic lung
Damage and repair, B cells –> IgE, oedema, thickening of walls, mucus, smooth muscle contraction
Radius of airway decreased –> flow decreases –> work of breathing must increase

Question 1

Define asthma

Answer 1

A chronic disorder
Reversible airflow obstruction
Airway wall inflammation and remodelling
Increased airway smooth muscle thickness
Increase in airway responsiveness to a variety of stimuli

Question 2

Describe the major precipitating factors for asthmatic attack

Answer 2

Histamine
Cold air
Exercise
Air pollution
Tobacco spores
Animals

Question 3

Describe the symptoms and signs of asthma and their pathological basis

Answer 3

Symptoms - wheeze, breathlessness, chest tightness, cough (often worse at night), variable airflow obstruction
Signs - eczema, hay fever, lethargy, hyper resonant during percussion, polyphonic wheeze during auscultation, chest deformity (barrel chest)

Question 4

Describe the tests used to assess the condition of a patient suspected of asthma, and how they are interpreted

Answer 4

PEFR (with bronchodilator to determine reversibility)
Spirometry (FEV1:FVC<70%)
Bronchial hyper responsiveness (BHR) 
Allergy testing 
CXR

Question 5

Describe, in outline, the principles of treatment of asthma

Answer 5

Education
Primary prevention - stop smoking, minimise exposure
Pharmacology:
Relaxants e.g. bronchodilator, B2 agonist - widen airway
Anti-inflammatory agents e.g. corticosteroids

Question 6

What is a wheeze and why does it occur?

Answer 6

A high pitched noise due to small airways narrowing by compression/obstruction during expiration