Management of Acute Severe Asthma in Adults in A&E

N.B. The flowchart has been adapted for local use. The original flowchart is available at: Scottish Intercollegiate Guidelines Network (SIGN). British guideline in the management of Asthma. Edinburgh: SIGN; 2019 (SIGN publication no. 158). Available from

All changes in the flowchart and in the notes below have been denoted by # and should not be taken as an endorsement by the original authors. 

Notes on Potential Discharge from A&E

  • Patients should be monitored closely after initial treatment to ensure sufficient clinical improvement prior to consideration of discharge.#
  • In all patients who received nebulised beta2 agonists prior to presentation, consider an extended observation period prior to discharge.#
  • If PEF <50% on presentation, prescribe prednisolone oral 40-50mg/day for a minimum of 5 days.#
  • Ensure all patients have a supply of inhaled steroid and beta2 agonist and check inhaler technique.#
  • Consider if adverse psychological factors (e.g. severe mental health issues, social isolation) may impact on safety of discharge and if so consider admission for observation for 24 hours.#
  • Arrange GP follow up within 2 working days post discharge.#
  • Ensure patient's electronic discharge letter is completed.#
  • Refer to asthma liaison nurse / chest clinic.

Peak Expiratory Flow Rate - Normal Values

For peak expiratory flow chart, see SIGN 158 Annex 4 at


Guideline reviewed and updated June 2021