Asthma Diagnosis and Management Flashcards
Asthma Phenotypes
Allergic
Non-allergic (no eosinophils)
Adult-onset
Asthma with persistent airflow limitation (appears like COPD, airway remodelling)
Asthma with obesity
Asthma Diagnosis
Clinical judgement which is supported by tests showing evidence of reversible/variable airflow
Asthma features
Episodic wheeze, dry cough, chest tightness, SOB
- Worse at night and morning (diurnal variability)
- Triggers (allergen, drugs, exercise, cold air)
- Atopic features
- Family history
- Bilateral expiratory wheeze on examination
- Low PEFR
Asthma diagnostic tests for all patients
FeNO
Spirometry Reversibility test
Asthma diagnostic test for patients aged 5-16y
Spirometry Reversibility Test
Only FeNO if negative/obstructive pattern (>35ppb)
Asthma diagnostic test for patients <5y
No tests
Diagnosis made on clinical judgement
Spirometry diagnostic result
FEV1:FVC <0.7
Many asthmatics may have normal spirometry especially when not symptomatic
Spirometry Reversibility diagnostic result
FEV1 >200ml
Fraction Exhaled NO diagnostic result
> 40ppb
Inducible NOS increases in inflammatory cells e.g. eosinophils
1 in 5 false positive/negative rate
May not have eosinophils due to asthma variability
Direct Challenge Testing diagnostic result
20% decrease in FEV1 with 8mg/ml
Low false negative rate
Performed with histamine/methacholine
PEFR Diurnal Variability diagnostic result
> 20% diurnal variability
2x daily PEFR readings over 2 weeks
Occupational Asthma
MUST refer to specialists if suspected
Lifestyle management
Avoid triggers Check adherence and technique Stop smoking Weight loss Vaccinations CNS
Step 1 Management
SABA
- Salbutamol
Step 2 Management
Begin if >3 episodes/week or night-waking
SABA + Low ICS
- Salbutamol
- Beclamethasone
