title: Conservative oxygen therapy in mechanically ventilated patients: a pilot before-and-after trial.
abstract: OBJECTIVE
  To assess the feasibility and safety of a conservative approach to oxygen therapy in mechanically ventilated ICU patients.
  
  
  METHODS
  Pilot prospective before-and-after study.
  
  
  METHODS
  A 22-bed multidisciplinary ICU of a tertiary care hospital in Australia.
  
  
  METHODS
  A total of 105 adult (18 years old or older) patients required mechanical ventilation for more than 48 hours: 51 patients during the "conventional" before period and 54 after a change to "conservative" oxygen therapy.
  
  
  METHODS
  Implementation of a conservative approach to oxygen therapy (target SpO2 of 90-92%).
  
  
  RESULTS
  We collected 3,169 datasets on 799 mechanical ventilation days. During conservative oxygen therapy the median time-weighted average SpO2 on mechanical ventilation was 95.5% (interquartile range, 94.0-97.3) versus 98.4% (97.3-99.1) (p < 0.001) during conventional therapy. The median PaO2 was 83 torr (71-94) versus 107 torr (94-131) (p < 0.001) with a change to a median FIO2 of 0.27 (0.24-0.30) versus 0.40 (0.35-0.44) (p < 0.001). Conservative oxygen therapy decreased the median total amount of oxygen delivered during mechanical ventilation by about two thirds (15,580 L [8,263-29,351 L] vs 5,122 L [1,837-10,499 L]; p < 0.001). The evolution of the PaO2/FIO2 ratio was similar during the two periods, and there were no difference in any other biochemical or clinical outcomes.
  
  
  CONCLUSIONS
  Conservative oxygen therapy in mechanically ventilated ICU patients was feasible and free of adverse biochemical, physiological, or clinical outcomes while allowing a marked decrease in excess oxygen exposure. Our study supports the safety and feasibility of future pilot randomized controlled trials of conventional compared with conservative oxygen therapy.
authors.affiliation: 1Department of Intensive Care, Austin Hospital, Heidelberg, VIC, Australia. 2Australian and New Zealand Intensive Care Research Centre, Melbourne, VIC, Australia.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Suzuki
authors.forename: Glenn M
authors.initials: GM
authors.lastname: Eastwood
authors.forename: Neil J
authors.initials: NJ
authors.lastname: Glassford
authors.forename: Leah
authors.initials: L
authors.lastname: Peck
authors.forename: Helen
authors.initials: H
authors.lastname: Young
authors.forename: Mercedes
authors.initials: M
authors.lastname: Garcia-Alvarez
authors.forename: Antoine G
authors.initials: AG
authors.lastname: Schneider
authors.forename: Rinaldo
authors.initials: R
authors.lastname: Bellomo
mesh_terms: D018806:APACHE; D000328:Adult; D000368:Aged; D001784:Blood Gas Analysis / Q000379:methods; D005260:Female; D006801:Humans; D018496:Hyperoxia / Q000209:etiology* / Q000517:prevention & control; D000860:Hypoxia / Q000517:prevention & control / Q000628:therapy*; D007362:Intensive Care Units; D008297:Male; D008875:Middle Aged; D010100:Oxygen / Q000008:administration & dosage* / Q000009:adverse effects; D010102:Oxygen Inhalation Therapy / Q000379:methods*; D010865:Pilot Projects; D011446:Prospective Studies; D012044:Regression Analysis; D012121:Respiration, Artificial / Q000379:methods*; D016896:Treatment Outcome
chemical_list: D010100:Oxygen