Asthma Flashcards
What is asthma?
A chronic obstructive inflammatory disease that affects both the large and small airways.
Patients will experience episodic bronchoconstriction.
Is asthma progressive?
No.
Does asthma affect the lungs?
No, it affects the airways only.
What are the two main groupings of asthma patients?
Atopic/Extrinsic (most common)
Non-atopic/Intrinsic
What is meant by atopic/extrinsic asthma?
It is caused by an external stimulus (often an allergic reaction).
May co-present with eczema and allergic rhinitis (the ‘atopic triad’). There is a genetic predisposition.
What is meant by non-atopic/intrinsic asthma?
It is caused by an internal stimuli.
What occurs in an asthma attack?
An immediate wave of bronchospasm (type 1 hypersensitivity), followed by a delayed inflammatory process (type 4 hypersensitivity).
What are precipitating factors in non-atopic asthma?
Animal dander
Infection
Cold/Damp conditions
Night/Early mornings
Is the airflow obstruction in asthma reversible?
Yes.
What is a typical presentation of asthma?
Episodic symptoms
Diurnal variability (often worse at night)
Dry cough, wheeze, SOB
Decreased exercise tolerance
Can chronic asthma cause irreversible damage?
Yes - this may result in airway remodelling.
This is characterised by:
Thickening of the basement membrane
Collagen deposition in the submucosa
Hypertrophy of the smooth muscle
How does spirometry show in an asthmatic patient?
They will have reduced expiratory ratio (FEV1/FVC < 70%).
This is reversible by up to 15% upon commencement of salbutamol therapy (only raises FEV1 - FVC remains constant).
What is the first-line for asthma treatment?
SABA and ICS.
What is the second-line for asthma treatment?
SABA and ICS and LABA.
If no response, then remove LABA, and increase ICS dose.
If some response, keep LABA and increase ICS dose.
What is third-line for asthma treatment?
SABA/ICS/LABA, plus one of the following:
LTRA
Theophylline
LAMA
Chromones