Asthma Flashcards
PATHOLOGY: Asthma
- Individual w/ genetic predisposition + environmental trigger = bronchial hypersensitivity
- Hypersensitivty + trigger = inflammation, oedema, bronchial constriction and increased mucous secretion
- Over time = remodelling = increase goblet cells, smooth muscle thickening
AETIOLOGY: Asthma
- Atopy
- Family history (esp. maternal)
- Parental smoking
What are common asthma triggers?
- Dust
- Animals
- Emotion
- Exercise
- Cold weather
- NSAIDs (10%)/B-blocker
CLINICAL FEATURES: Asthma
None when well
Symptoms
- Wheeze
- Cough (nocturnal esp)
- SOB
- Chest tightness
- Night-time waking
Signs
- Tachypnoea
- Tachycardia
- Cyanosis
- Diurnal variation
INVESTIGATION: Asthma
Can begin treatment if good Hx
NB: If adult onset MUST ask about foreign travel/occupation
- Peak flow diary
- Exercise tests
- Skin prick tests
- Spirometry - if adult
- Exclusion*
- CXR
Example spirometry results for asthmatic?
Must be during exacerbation of symptoms
- Before inhaler
- FEV1 = reduced
- FVC = reduced
- FEV1/FVC = reduced (OBSTRUCTIVE)
- After inhaler
- FEV1 = Increased >12%
- FVC = Increased
- FEV1/FVC = IMPROVED
MANAGEMENT: Adult Asthma
- Conservative*
- Trigger avoidance, no smoking, weight loss in obesity
- Medical*
- See stepwise management
NB: Must check inhaler technique before stepping up management
STEP 1 MANAGEMENT: Adult Asthma
(mild/intermittent or exercise induced)
Short-acting inhaled B agonist PRN (SABA)
e.g. SALBUTAMOL
SE: essential tremor, tachycardia
Step up if using >2 times per week
STEP 2 MANAGEMENT: Adult Asthma
(Mild persistent)
Add Low-dose steroid inhaler
e.g. 400mcg Beclomethasone (max 800mcg)
SE: oral candidiasis, easy bruising, osteoporosis, DM, HTN
NB: Must wash mouth out after use
STEP 3 MANAGEMENT: Adult Asthma
(moderate persistent)
Add LABA
e.g. SALMETEROL / FORMOTEROL
Assess control on LABA
- Good = continue LABA
- Benefit = continue LABA + increase steroids 800mcg
- Inadequete = stop LABA + increase steroids + consider step 4
STEP 4 MANAGMENT: Adult
- *Consider**
1. increasing inhaled steroid up to 2000 mcg/day
OR
- Add Leukotriene receptor antagonist (eg MONTELUKAST) / SR theophylline / B2 agonist tablet
NB: Theophylline may need blood monitoring
STEP 5 MANAGEMENT: Adult Asthma
Must be under respiratory physician
- Daily steroid tablet
AND
- High dose inhaled steroid (2000mcg)
CONSIDER:
- Immunosuppressants
STEPWISE MANAGEMENT: Children <5 Asthma
1 As-required reliever therapy:
- short-acting beta2-agonist
2. Regular preventer therapy: - inhaled Corticosteroids, 200-400mcg/day*
OR,
- Leukotriene receptor antagonist
3. Children aged 2-5 years: - trial of a leukotriene receptor antagonist. If already taking leukotriene receptor antagonist reconsider inhaled corticosteroids
4. Refer to a respiratory paediatrician
