Asthma

Question 1

Define

Answer 1

Chronic respiratory condition associated with airway inflammation and hyper-responsiveness

MOST COMMON chronic childhood respiratory disorder

It can be well controlled but is still an important cause of absence from school, restricted activity and anxiety

THREE patterns of wheezing:
1. Viral episodic wheezing- wheeze only in response to viral infections
2. Multiple trigger wheeze- wheeze in response to multiple triggers and is more likely to develop into asthma over time

Viral Induced/Episodic Wheeze (VEW) – from small airways more likely to narrow and obstruct with inflammation and aberrant immune response to viral infection -> episodic nature resolves by 5yo – thought to be on spectrum:

Bronchiolitis (<1yo) -> viral-induced wheeze (1-5yo) -> asthma (>5yo)

Mutliple trigger wheeze (the prodrome of atopic asthma)
* Multiple-Trigger Wheeze- wheeze that is triggered by several stimuli- e.g. cold air, dust, animal dander, exercise, food allergens
* A significant proportion go on to develop asthma
* It is classified as atopic asthma when recurrent wheezing is associated with symptoms between viral infections (interval symptoms) and evidence of allergy to ≥1 inhaled allergens e.g. house dust mite, pollens are present

Atopic asthma is strongly associated with:
1. Eczema 2. Rhinoconjunctivitis 3.Food allergy

But
* Croup occurs between 6m and 6yo (it does not really lie on the above spectrum though)
* RFs: maternal smoking (ante-/post-natal), prematurity, FHx of VEW

Question 2

Clinical features

Answer 2

Wheeze (end-expiratory polyphonic), cough, SoB, chest tightness

• Symptoms worst at night / early morning
• Symptoms with non-viral triggers
• Personal or FHx of atopy
• Positive response to asthma bronchodilator therapy

Examination:

• Hyperinflated chest ± accessory muscle use
• Polyphonic expiratory wheeze with a prolonged expiratory phase (if long-standing asthma)
• Harrison’s sulci (depressions at base of thorax where diaphragm has grown in muscular size)
• Check for evidence of eczema and allergic rhinitis
• Growth should be monitored (is usually normal but can be affected by severe asthma)

Question 3

Investigations

Answer 3

<5yo: clinical diagnosis

If > 5 years old- offer/ consider:
* Spirometry- FEV1/ FVC < 70% of expected = positive result
* Bronchodilator Reversibility- consider in children with a positive spirometry result. An improvement in FEV1 of > 12% = positive result
* Peak Expiratory Flow Variability- consider peak flow monitoring for 2-4 weeks in children if there is diagnostic uncertainty (variability over 20%) - peak flow diaries
* Use height and age chart to see their PEFR
* FeNo Test- consider if there is diagnostic uncertainty after initial assessment. A level > 35ppb = positive test

NOTE: this is a measure of airway inflammation

• Skin-prick testing for common allergens may be performed (after a formal diagnosis of asthma has been made) as it helps identify triggers and demonstrates atopy
• If an adult, young person or child with symptoms suggestive of asthma cannot perform a particular test, try to perform at least 2 other objective tests. Diagnose suspected asthma based on symptoms and any positive objective test results.
• Vital signs: BP, HR, RR, SpO2, temperature
• PEFR ± diary!
• Spirometry + bronchodilator test therapy (improvement of 12%+) ± FeNO testing

Question 4

Management

Question 5

Prognosis

Question 6

PACES

Answer 6

Important questions to ask:

• When were they diagnosed with asthma?
• CHECK IF THEY HAVE ECZEMA OR HAYFEVER
• How frequent are the symptoms?
• How many times have they used the blue inhaler?
• Do they use a spacer?
• Does it help resolve the issue?
• Poorly controlled if they use blue inhaler regularly
• What triggers the symptoms? Specifically, are sport and general activities affected by the asthma?
• Allergies, exercise, infection
• Any chest infections and how were they treated?
• How often is sleep disturbed by asthma? How often does it wake you up from your sleep or earlier than usual in the morning?
• How severe are the interval symptoms between exacerbations?/ Usual symptoms during the day?
• Does it interfere with activities?
• How much school has been missed due to asthma?
• How would you rate your asthma control?
• Have they been in hospital due to asthma? Did they need oxygen?
• Check about smoking and pets
• Esp smoking at home

CHECK ABOUT THEIR PERSONALISED ASTHMA PLAN and if they are sticking to it

(Asthma and lung UK)
https://www.asthma.org.uk/e75bf921/globalassets/health-advice/resources/children/my-asthma-plan-2021-v5-multi-media-live.pdf