Asthma Flashcards
What is required for a diagnosis of asthma?
Demonstration of REVERSIBLE airflow obstruction by spirometry or peak flow rate
The pathogenesis of asthma is explained by the 3 S’s which are?
Spasm of smooth muscle
Swelling/ oedema of bronchial mucosa
Secretions from hypertrophic mucous glands - thick+tenacious mucous
Immune cells involved in asthma?
X3
Eosinophils, mast cells and lymphocytes
Host risk factors for Asthma
Atopic tendencies
Environmental risk factors for asthma
X2
Allergens (dust mites, animal dander, pollen, moulds)
Irritants (Cold air, exercise, smoke, fumes, URTIs)
Diagnosis of asthma on the basis of lung function tests
1) decreased baseline
bronchodilator response test, oral steroid trial, serial home peak flow charting
2) Normal baseline
Serial home peak flow measurements must show a drop of 20% post trigger exposure/exercise.
What is an oral steroid trial for asthma?
Describe in three steps
Measure FEV1/PEF
Then give 40mg Prednisone PO for 2 weeks
Follow up and assess response
What do you find on examination in an asthmatic?
Wheeze
Hyperinflation
OR
Nothing
Occupational history red flags for ?asthma
X6
Latex, baking, spray painting, plastics, animals, platinum industries
Medication history red flags for asthma
X3
Aspirin
NSAIDS
B-blockers
Benefits of inhalation treatment for asthma
X6
Targets site of disease Lower dose Lower systemic absorption Fewer side effects Patient can tritrate the dose Rapid onset
Drawbacks of inhalation treatment for asthma
X4
Poor inhaler technique
Cultural suspicion
Patient fear of addiction
Overuse/underuse difficult to monitor
When is it more likely to be COPD as opposed to asthma?
X5
Onset after 50 Significant smoking history >15 PYs Constant SOB and cough Slow progression Poor treatment response
When is it more likely to be asthma as opposed to COPD?
X4
Young age of onset
Patient or family history of atopy or asthma
Variation in symptoms: Episodic/ diurnal variation/ day to day variation
Good response to treatment
Other differentials for asthma
Upper airway obstruction Local bronchial obstruction - e.g. Tumor Cardiac disease Bronchiectasis Recurrent pulmonary emboli
Name two types of reliever therapy
Short acting B2 agonists
Anti-cholanergics
Short acting B2 agonists:
Time of onset
Side effects
Example of a drug
5-15 minutes
Tremor/palpitations
Salbutamol
Anti cholanergics:
Time of onset
Side effects
Example of a drug
Within 30 minutes
Urinary retention, worsen closed angle glaucoma, paradoxical bronchospasm, hypersensitivity
Name four classes of controller therapy
Steroids
Long acting B2 agonists
Leukotriene receptor modifiers
Sustained release theophyllines
Steroids
Time of onset
Side effects
Example of a drug
2-3 hours
Bruising, thrush, hoarseness
Budeflam (inhaled), prednisone (oral)
Long acting B2 agonists:
Length of action,
Dosing interval
Provides 12+ hours of bronchodilation
Used BD
Leukotriene receptor modifiers:
What TYPES of asthma is this treatment most effective for?
Example
Exercise and aspirin induced asthma
Monteleuklast
Sustained release theophyllines Onset Side effects Example Dangers?
30 minute onset
Nausea, diarrhoea, vomiting, dyspepsia, muscle cramps, palpitations, arrythmias
Theophilus, Nuelin SA
Danger - narrow therapeutic index
Approach to acute severe asthma
3
Assess
First line treatment (15-20) minutes
Assess response to treatment + plan
