Asthma

• How is asthma diagnosed in under 5s?


  Clinically
• How common is asthma in children?


  1 in 11 children

  Most common chronic condition in childhood
• What are the RFs of paediatric asthma?


  Hx of atopy

  FHx of atopy

  Preterm birth & low birth weight

  Obesity in childhood

  Exposure to air pollution, damp or mould in the home & second-hand smoke
• What can trigger asthma?


  Air pollution

  Dust mites

  Viral resp tract infections

  Exercise

  Cold air

  Strong emotions

  Medications (e.g. NSAIDs)
• What are the signs & symptoms of acute asthma?


  Progressively worsening SOB

  Signs of resp distress

  Tachypnoea

  Expiratory wheeze

  Reduced air entry

  Can be silent chest
• What is the management of acute asthma?


  OSHITME

  O2

  SABA

  Hydrocortisone

  Ipratropium

  Theophylline

  Magnesium

  Escalate

  Also give Abx if bacterial cause is suspected.
• What is the step-down regime of SABA? When is it considered safe to discharge?


  10 puffs 2 hourly

  10 puffs 4 hourly

  6 puffs 4 hourly

  4 puffs 6 hourly

  Safe to discharge when child is well on 4 puffs 6 hourly.

  Can be prescribed reducing regime at home

  -> 6 puffs 4 hourly (for 48 hrs) -> 4 puffs 6 hourly (for 48 hrs) -> 2-4 puffs as required
• What is the paediatric presentation suggestive of asthma?


  Episodic symptoms w/intermittent exacerbations

  Diurnal variability (worse @ night & early morning)

  Dry cough w/wheeze & SOB

  Hx of other atopic conditions

  FHx of atopy

  Bilateral polyphonic wheeze

  Symptom improvement w/bronchodilators

  Possible chest hyperinflation
• What is the paediatric presentation that indicates a diagnosis other than asthma?


  Wheeze only related to coughs & colds -> more suggestive of viral-induced wheeze

  Isolated or productive cough

  Normal Inx

  No response to bronchodilators

  Unilateral wheeze -> focal lesion, inhaled foreign body, infection
• What are the DD of asthma?

  Resp tract infection

  Cystic fibrosis

  Bronchopulmonary dysplasia

  Bronchiectasis

  GORD

  Foreign body inhalation

  Bronchiolitis
• What is bronchopulmonary dysplasia?


  Chronic lung disease

  Caused by prematurity, usually pts who previously required ventilation in infancy
• What are the Inx for asthma (over 5)?


  Spirometry w/bronchodilator reversibility

  FeNO (> 35 ppb = positive)

  Peak flow
• What is the lowest age a child will be diagnosed with asthma?


  2-3
• What is the medical management of asthma in under 5s?

  Stepwise management

  1. SABA
  2. Low dose ICS or LTRA (oral montelukast)
  3. Low dose ICS + LTRA
  4. Refer to specialist
• What is the medical management of asthma in 5-12 yrs?


  Stepwise

  1. SABA (as required)
  2. Low dose ICS
  3. LABA
  4. Medium dose ICS (consider adding LTRA or theophylline)
  5. High dose ICS
  6. Refer to specialist
• What is the medical management of asthma in over 12s?


  Same as adults

  1. SABA
  2. Low dose ICS
  3. LABA (continue only if good response)
  4. Medium dose ICS (consider trial LTRA, theophylline or LAMA)
  5. High dose ICS
  6. Refer to specialist
  7. Possible oral steroids at lowest dose
• Apart from medication, what is the other management of asthma?


  Regular reviews (at least annually)

  Check inhaler technique (each review & each change in inhalers)

  Education on modifiable RFs (smoke exposure, household chemicals, obesity)
• What are the possible complications of asthma?


  Acute exacerbations

  Reduced growth

  Poor school attendance

  Low mood & self-esteem
• Some children may 'grow out' of their asthma, or asthma may become less severe with age.
• Pathophys - asthma


  Initial trigger exposure → activates immune cells (mast cells, DCs, macrophages, Th2) → release histamine, leukotrienes & cytokines (IL-4, IL-5, IL-9, IL-13) → inflam → bronchoconstriction (smooth muscle contraction) → narrows airway → SOB

  Stimulate goblet cells → excess mucous production → more airflow obstruction → cough & wheeze

  Chronic inflammation → structural changes → persistent airflow limitation & reduces treatment effectiveness

  Combined effects of inflam, airway hyperresponsiveness, mucus overproduction, & remodelling = episodic symptoms (SOB, wheeze, cough)