title: Initial oxygen management in patients with an exacerbation of chronic obstructive pulmonary disease.
abstract: 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.
  
  
  OBJECTIVE
  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.
  
  
  METHODS
  Retrospective audit.
  
  
  METHODS
  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.
  
  
  CONCLUSIONS
  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.
authors.affiliation: Department of Respiratory Medicine, Medicine, Norfolk and Norwich University Hospital, Norwich, Norfolk, UK. hannahd@doctors.org.uk
authors.forename: H J
authors.initials: HJ
authors.lastname: Durrington
authors.forename: M
authors.initials: M
authors.lastname: Flubacher
authors.forename: C F
authors.initials: CF
authors.lastname: Ramsay
authors.forename: L S G E
authors.initials: LS
authors.lastname: Howard
authors.forename: B D W
authors.initials: BD
authors.lastname: Harrison
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000552:Ambulances; D000553:Ambulatory Care / Q000379:methods; D002245:Carbon Dioxide / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D008485:Medical Audit / Q000379:methods; D008875:Middle Aged; D010100:Oxygen / Q000502:physiology; D010102:Oxygen Inhalation Therapy / Q000009:adverse effects / Q000379:methods*; D029424:Pulmonary Disease, Chronic Obstructive / Q000628:therapy*; D012189:Retrospective Studies; D013997:Time Factors
chemical_list: D002245:Carbon Dioxide; D010100:Oxygen