Asthma – Definitions & Management

Moderate Asthma

  • Peak Flow 50-75%
  • No features of acute severe asthma

Acute Severe Asthma Attack

Defined of any one of:

  • Peak Flow 33-50% best of predicted
  • Respiratory Rate 25 or more
  • Heart Rate 110 or more
  • Inability to complete sentences in one breath.

Acute Severe:

Mum, Fuse, more than Knife Lollys,

Mum has had acute severe asthma, she’s unable to complete sentances in one breath… picture Mum (33) smashing a fuse  (50) box up with a knife (25) and loads of lollys (110) coming out

Life Threatening Asthma Attack

Defined as any one of:

  • Peak flow less than 33%
  • O2 sats less than 92%
  • PaO2 < 8kPa
  • Normal PaCO2
  • Silent Chest
  • Cyanosis
  • Poor Respiratory effort
  • Arrhythmia
  • Exhaustion / altered conscious level

Picture Katie in ITU (life threatening)… with mum (33) by her side holding a gun (92)  at the doctors Shoe (8)



There’s no stepwise management plan now but here’s a 7 point summary.

  1. Newly diagnosed asthma –>  SABA
  2. If not controlled on step 1 or using SABA 3 times a week, or waking at night –> SABA + Low Dose Corticosteroid
  3. SABA + Low Dose Corticosteroid + Leucotriene Receptor Antagonist (LTRA)
  4. SABA + Low Dose ICS + LABA +/- LTRA (depending on patient’s response to LTRA)
  5. SABA + LTRA. Switch ICS/LABA for maintainence and reliever therapy (MART) which includes a low dose ICS
  6. SABA +/- LTRA + Medium Dose ICS MART, or consider changing back to a fixed dose of a moderate Dose ICS and a separate LABA
  7. SABA +/- LTRA + one of the following:
    1. Increase ICS to high dose
    2. A trial of an additional drug (for example a long acting muscarinic receptor antagonist or theophylline)
    3. Seek advice from professional with expertise in asthma