Initial oxygen management in patients with an exacerbation of chronic obstructive pulmonary disease

QJM. 2005 Jul;98(7):499-504. doi: 10.1093/qjmed/hci084. Epub 2005 Jun 13.


Background: The Norfolk and Norwich University Hospital (NNUH) is situated in rural Norfolk, and ambulance journey times are often >30 min. Longer ambulance journeys could lead to a greater risk of hypercapnia, if inappropriately high concentrations of oxygen are given during an exacerbation of COPD.

Aim: To investigate the effect of high concentration oxygen (HCO, FiO(2) > 0.28) on COPD patients, and the outcome of instituting a simple protocol to reduce such exposure.

Design: Retrospective audit.

Method: An audit was conducted of all patients admitted with an exacerbation of COPD to the NNUH during the 2 months from 1 December 2001 to 31 January 2002 (n = 108). Results were shared with paramedics, and guidelines agreed for the initial provision of lower concentrations of oxygen (LCO, FiO(2) < or = 0.28). A second audit was conducted a year later between 1 December 2002 and 31 January 2003 (n = 103).

Results: HCO caused significant (p < 0.01) acidosis and inappropriately high PaO(2) and PaCO(2), compared to initial LCO therapy. There was a significantly increased complication rate during admission (p < 0.01) in those COPD patients receiving HCO compared to LCO, particularly when ambulance journeys exceeded 30 min. The second audit demonstrated a significant (p < 0.001) reduction in the number of patients initially receiving HCO, but the complication rate was unaltered.

Discussion: A simple intervention, such as providing paramedics with 28% Venturi masks, can reduce the number of COPD patients exposed to HCO. A randomized controlled trial is long overdue to establish whether HCO or LCO as initial management is associated with the most favourable prognosis in different hospital settings.

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Ambulances
  • Ambulatory Care / methods
  • Carbon Dioxide / physiology
  • Female
  • Humans
  • Male
  • Medical Audit / methods
  • Middle Aged
  • Oxygen / physiology
  • Oxygen Inhalation Therapy / adverse effects
  • Oxygen Inhalation Therapy / methods*
  • Pulmonary Disease, Chronic Obstructive / therapy*
  • Retrospective Studies
  • Time Factors


  • Carbon Dioxide
  • Oxygen