title: High frequency oscillatory ventilation compared with conventional mechanical ventilation in adult respiratory distress syndrome: a randomized controlled trial [ISRCTN24242669].
abstract: BACKGROUND
  To compare the safety and efficacy of high frequency oscillatory ventilation (HFOV) with conventional mechanical ventilation (CV) for early intervention in adult respiratory distress syndrome (ARDS), a multi-centre randomized trial in four intensive care units was conducted.
  
  
  METHODS
  Patients with ARDS were randomized to receive either HFOV or CV. In both treatment arms a priority was given to maintain lung volume while minimizing peak pressures. CV ventilation strategy was aimed at reducing tidal volumes. In the HFOV group, an open lung strategy was used. Respiratory and circulatory parameters were recorded and clinical outcome was determined at 30 days of follow up.
  
  
  RESULTS
  The study was prematurely stopped. Thirty-seven patients received HFOV and 24 patients CV (average APACHE II score 21 and 20, oxygenation index 25 and 18 and duration of mechanical ventilation prior to randomization 2.1 and 1.5 days, respectively). There were no statistically significant differences in survival without supplemental oxygen or on ventilator, mortality, therapy failure, or crossover. Adjustment by a priori defined baseline characteristics showed an odds ratio of 0.80 (95% CI 0.22-2.97) for survival without oxygen or on ventilator, and an odds ratio for mortality of 1.15 (95% CI 0.43-3.10) for HFOV compared with CV. The response of the oxygenation index (OI) to treatment did not differentiate between survival and death. In the HFOV group the OI response was significantly higher than in the CV group between the first and the second day. A post hoc analysis suggested that there was a relatively better treatment effect of HFOV compared with CV in patients with a higher baseline OI.
  
  
  CONCLUSIONS
  No significant differences were observed, but this trial only had power to detect major differences in survival without oxygen or on ventilator. In patients with ARDS and higher baseline OI, however, there might be a treatment benefit of HFOV over CV. More research is needed to establish the efficacy of HFOV in the treatment of ARDS. We suggest that future studies are designed to allow for informative analysis in patients with higher OI.
authors.affiliation: Intensive Care, University Medical Centre Utrecht, The Netherlands. c.w.bollen@umcutrecht.nl
authors.forename: Casper W
authors.initials: CW
authors.lastname: Bollen
authors.forename: Gijs Th J
authors.initials: GT
authors.lastname: van Well
authors.forename: Tony
authors.initials: T
authors.lastname: Sherry
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Beale
authors.forename: Sanjoy
authors.initials: S
authors.lastname: Shah
authors.forename: George
authors.initials: G
authors.lastname: Findlay
authors.forename: Mehran
authors.initials: M
authors.lastname: Monchi
authors.forename: Jean-Daniel
authors.initials: JD
authors.lastname: Chiche
authors.forename: Norbert
authors.initials: N
authors.lastname: Weiler
authors.forename: Cuno S P M
authors.initials: CS
authors.lastname: Uiterwaal
authors.forename: Adrianus J
authors.initials: AJ
authors.lastname: van Vught
mesh_terms: D018806:APACHE; D000293:Adolescent; D000328:Adult; D000368:Aged; D001784:Blood Gas Analysis; D001794:Blood Pressure; D018592:Cross-Over Studies; D005260:Female; D006612:High-Frequency Ventilation / Q000379:methods; D006801:Humans; D008297:Male; D008875:Middle Aged; D010102:Oxygen Inhalation Therapy; D012121:Respiration, Artificial / Q000379:methods*; D012128:Respiratory Distress Syndrome / Q000145:classification / Q000628:therapy*; D016019:Survival Analysis; D016896:Treatment Outcome