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The crashing patient: Life-threatening asthma


No or limited improvement following initial treatment

Symptoms: Worsening dyspnoea, unable to speak/speaking words only, agitation, drowsiness, fatigue, paradoxical chest wall movements

Vital signs: HR 120, cardiac arrhythmia, saturations

Clinical signs: Quiet/silent chest, cyanosis

VBG/ABG: Worsening hypercarbia, hypoxia, PaCO2 within normal range despite low PaO2


For a flowchart on the management of the crashing asthmatic - click here.

1. 10-12L/min O2 via a nebuliser mask / high flow nasal prongs and continuous salbutamol nebulisation. Aim sats at least 95%.

2. If tiring but still cooperative patients will require a trial of non-invasive ventilation with BIPAP.

  • Settings: FiO2 1.0, IPAP 10 and above, EPAP 5

  • Titrate support according to ABGs

  • Nebulise bronchodilators through the BIPAP circuit

3. Simultaneously start regular ipratropium bromide nebulisation 250-500mcg every 20 minutes.

4. IV hydrocortisone 100mg (if not already given)

5. IV magnesium sulphate infusion - click here for infusion guide.

6. Treatment preferences at this stage may vary between institutions/clinicians and national guidelines but include:

7. If patient is peri-arrest give adrenaline as a bolus. Adrenaline 500mcg (0.5mLs) of 1:1000 IM or 500mcg (5mLs) of 1:10000 from an adrenaline minijet given slowly IV.

8. If failing BIPAP and maximal medical therapy in progress will need intubation and urgent ICU admission.


  • Not involving the most experienced airway doctor available.

  • Not involving your critical care colleagues.

  • Not appreciating the potential for patient to deteriorate:

    • Hypoxia and respiratory arrest

    • Hypotension and cardiovascular collapse – reduced preload with positive pressure ventilation (patients are pre-load dependant).

  • Taking patient off BIPAP and lying patient flat pre delivery of RSI drugs.

  • Using conventional ventilation strategies.

  • Not adequately sedating and paralysing patient post intubation.

  • Failure to deliver nebulisers via the ventilation circuit.

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