infections, allergens, occupational exposures, food additives and chemicals, irritants, aspirin and strong emotions
What lymphocyte is the inflammatory reaction in asthma led by?
Th2 lymphocytic response
Investigations for Asthma
- Spirometry and reversibility
- NO test -> rarely used
- Blood test -> eosinophil
- Histamine challenge
- Skin prick/IgE CXR -> mostly to exclude and is usually clear.
Criteria to determine if a person has a high probability of asthma
- recurrent episodes
- symptom variability
- absence of symptoms of alternative diagnosis
- observed wheeze
How to diagnose Asthma using peak flow?
record peak flow qds for 2-4 wks
Mild PEF reading?
>80% of best/predicted
Moderate PEF reading?
50-80% of best/predicted
Acute Severe PEF reading?
Life threatening PEF reading?
What would be considered as a positive result for asthma when doing a bronchodilator reversibility test?
an increase in FEV1 of 12% (or more) and an increase in volume of 200 ml (or more)
example of inhaled steroid?
example of oral steroid?
example of muscarinic antagonist?
example of leukotriene receptor antagonist and what type of asthma is it used to treat?
montelukast and allergy induced asthma
Is magnesium used more for asthma or COPD?
Criteria for well controlled asthma?
don't experience: daytime symptoms night time waking need for rescue meds asthma attacks limited activity abnormal lung fn minimal side effects
Treatment pathway for asthma
1. SABA 2. ICS 3. LABA 4. stop LABA and increase ICS 5. consider increasing ICS + alternative treatment + specialist care 6. Oral steroid
Management of acute asthma attack?
Oxygen 5mg salbutamol in nebuliser or 50 spacer puffs Prednisolone 40-50mg for 5 days Admit severe asthma
When should respiratory specialist follow up patients who've had a severe asthma attack?
at least 12 months after admission
When should primary care be informed of asthma attack?
within 24 hours of the attack
Features of a moderate asthma attack
increasing symptoms PEF >50-75% no signs of severe asthma
Features of a severe asthma attack
any one of: PEF 33-50% RR >25 HR >110 can't complete sentence in one breath
Features of a life threatening asthma attack
features of severe asthma plus any one of the following: PEF <33% SpO2 <92% silent chest cyanosis poor respiratory effort arrhythmia exhaustion low GCS hypotension
Features of near fatal asthma attack
raised PaCO2 and or requiring mechanical ventilation
Things you want to rule out when suspecting COPD
Lung cancer, PE and asthma
Investigations for COPD
- FBC (eosinophilia and anaemia)
- CXR (hyperinflation, bullae and flattened diaphragms)
- spirometry with reversibility
What is the only intervention proven to have a prognostic effect on COPD?
Treatment of patient with stable COPD
stop smoking, vaccines, exercise
Management of COPD Exacerbations
Increase frequency of SABA
Antibiotics (Amoxicillin 500mg tds)
Offer prednisolone 30mg
(some patients given rescue packs)
Stage 1 (Mild) COPD FEV1
Stage 2 COPD (Moderate) FEV1
Stage 3 (Severe) COPD FEV1
Stage 4 (very severe) COPD FEV1
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