Terms used in the guideline

Acute exacerbation of COPD

An exacerbation is a sustained worsening of the person's symptoms from their usual stable state, which is beyond normal day-to-day variations, and is acute in onset. Commonly reported symptoms are worsening breathlessness, cough, increased sputum production and change in sputum colour. (NICE guideline on COPD in over 16s).

Severity of exacerbation

A general classification of the severity of an acute exacerbation (NICE guideline on COPD in over 16s; Oba Y et al. [2017]) is:

  • mild exacerbation: the person has an increased need for medication, which they can manage in their own normal environment

  • moderate exacerbation: the person has a sustained worsening of respiratory status that requires treatment with systemic corticosteroids and/or antibiotics

  • severe exacerbation: the person experiences a rapid deterioration in respiratory status that requires hospitalisation.

Anthonisen et al. (1987) classified the type of an acute exacerbation based on 3 cardinal exacerbation symptoms:

  • increased breathlessness

  • increased sputum volume

  • sputum purulence.

The presence all 3 symptoms was defined as type 1 exacerbation; 2 of the 3 symptoms was defined as type 2 exacerbation; and 1 of the 3 symptoms with the presence of 1 or more supporting symptoms and signs was defined as type 3 exacerbation. This classification has been widely used to determine the severity of exacerbation in research studies, with more symptoms indicating a more severe exacerbation.

Supporting symptoms were:

  • cough

  • wheezing

  • fever without an obvious source

  • upper respiratory tract infection in the past 5 days

  • respiratory rate increase or heart rate increase 20% above baseline.

  • Public Health England
  • National Institute for Health and Care Excellence (NICE)