Asthma

• Asthma is a chronic inflammatory airway disease leading to variable airway obstruction. The smooth muscle in the airways is hypersensitive and responds to stimuli by constricting, narrowing the space for air to flow through. This bronchoconstriction is reversible with bronchodilators, such as inhaled salbutamol.
• Asthma is one of several atopic conditions, including eczema, allergic rhinitis (e.g., hay fever) and food allergies.
• Diagnosis for children aged 5-16:

  1. Measure FeNO level - 35ppb or greater suggests asthma
  2. Bronchodilator reversibility with spirometry - FEV1 increase is 12% or more from baseline suggests asthma
  3. Measure PEF twice daily for 2 weeks - variability of 20% or more suggests asthma
  4. Skin prick testing to house dust mite, or measure total IgE level and blood eosinophil count
• Children under 5 with suspected asthma:

  • 8-12 week trial of BD paediatric low-dose inhaled ICS as maintenance therapy
  • SABA for reliever therapy
  • Perform objective diagnostic tests if still symptomatic once 5 years old
• First line therapy in newly diagnosed asthmatics 5-11:

  • Twice daily paediatric low-dose ICS
  • AND a SABA for as needed relief
• If symptoms not controlled with BD ICS + SABA, assess ability to manage MART regimen:

  • Able to manage MART Regimen = start MART
  • Unable to manage = start conventional regimen
• MART regimen:

  1. Paediatric low-dose MART (ICS plus LABA)
  2. Paediatric moderate-dose MART
  3. Refer to specialist
• Conventional regimen:

  1. Add an LTRA to BD low-dose ICS for a trial period of 8-12 weeks, continue SABA
  2. Twice daily paediatric low-dose ICS/LABA combination (with or without an LRTA), continue SABA
  3. Twice daily paediatric moderate-dose ICS/LABA combination (with or without an LTRA), continue SABA
  4. Refer to specialist
• There is evidence that inhaled steroids can very slightly reduce growth velocity and may cause a slight reduction in final adult height of up to 1cm when used long-term (for more than 12 months). This effect is dose-dependent, meaning it is less of a problem with smaller doses.
• MDI technique without a spacer:

  • Remove the cap
  • Shake the inhaler (depending on the type)
  • Sit or stand up straight
  • Lift the chin slightly
  • Fully exhale
  • Make a tight seal around the inhaler between the lips
  • Take a steady breath in whilst pressing the canister
  • Continue breathing in for 3 – 4 seconds after pressing the canister
  • Hold the breath for 10 seconds (or as long as comfortably possible)
  • Wait 30 seconds before any further doses
  • Rinse the mouth after using a steroid inhaler
• MDI technique with a spacer:

  • Assemble the spacer
  • Shake the inhaler (depending on the type)
  • Attach the inhaler to the correct end
  • Sit or stand up straight
  • Lift the chin slightly
  • Make a seal around the spacer mouthpiece or place the mask over the face
  • Spray the dose into the spacer
  • Take steady breaths in and out 5 times until the mist is fully inhaled
• Spacers are cleaned once a month with warm water and washing up liquid. They should avoid scrubbing the inside and allow the spacer to air dry to avoid creating static. Static can interact with the mist and prevent the medication from being inhaled.