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Asthma

Services

RIE: Dr Tracey Bradshaw
WGH: Dr Peter Reid  
St John’s: Dr Donald Noble

Diagnosis of asthma

When to consider a diagnosis of asthma;

  • Has the patient had an attack, or recurrent attacks of wheezing?
  • Does the patient have a troublesome cough at night?
  • Does the patient have a wheeze or cough after exercise?
  • Does the patient have wheeze, chest tightness, or cough after exposure to airborne allergens or pollution?
  • Do the patient’s colds go to the chest or take more than 10 days to clear up?
  • Are the symptoms improved by appropriate anti-asthma treatment

How to diagnose asthma

Consider the diagnosis if the patient has 1 or more of the following;
Symptoms  

  • Wheeze
  • SOB
  • Chest tightness
  • Cough

Signs

  • None (common)
  • Wheeze
  • Tachypnoea

Helpful additional information

  • Symptoms worse at night and/or early morning
  • Personal or family history of asthma or atopy
  • History of worsening after use of NSAIDs or β blockers   
  • Recognised triggers- e.g. allergens, cold air, exercise

Objective measurements that can be performed in primary care

  • 20% diurnal variation on 3 or more days in a week for 2 weeks on PEF diary
    or
  • FEV1 ≥ 15% (and 200mls) increase after short acting β2 agonist (e.g. Salbutamol 400mcg by pMDI + spacer or 2.5mg by nebuliser)
    or
  • FEV1 ≥ 15% (and 200mls) increase after trial oral steroids (prednisolone 40mg/day for 14 days)

Using FEV1 or PEF as a response to treatment is of limited value in patients with near/normal lung function. Assess symptomatic response to treatment using a validated tool e.g. Asthma Control Test

Who to refer:

  • Diagnosis unclear or in doubt
  • Spirometry or PEF not appropriate to clinical picture
  • Suspected occupational asthma- refer Dr Reid
  • Patients who remain symptomatic and/or have impaired lung function and/or frequent exacerbations despite treatment at Step 4 BTS/SIGN Guidelines
  • Previous life-threatening or near-fatal attack (How to recognise patients at-risk of near-fatal asthma opens a new window)

Who not to refer:

  • Mild intermittent, or mild to moderate persistent asthma who are well controlled unless any features documented above

How to refer:

  • Use Gateway to refer to these services
  • Dictation Checklist opens a new window
  • FEV1 or PEF if spirometry not available
  • assessment of adherence (prescription records for asthma medications over past 12 months)
  • CXR