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High-frequency oscillation does not improve outcomes in adults with ARDS

Clinical Question:
Does high-frequency oscillation ventilation improve outcomes in patients with acute respiratory distress syndrome?

Bottom Line:
High-frequency oscillation ventilation (HFOV) does not improve outcomes in patients with acute respiratory distress syndrome (ARDS), and may well worsen them. The authors speculate that previous studies may have seen a benefit because they were comparing HFOV to older, less-effective standard ventilation strategies. (LOE = 1b)

Ferguson ND, Cook DJ, Guyatt GH, et al, and the OSCILLATE Trial Investigators, for the Canadian Critical Care Trials Group. High-frequency oscillation in early acute respiratory distress syndrome. N Engl J Med 2013;368(9):795-805.  [PMID:23339639]

Study Design:
Randomized controlled trial (nonblinded)



Inpatient (ICU only)

HFOV uses very small tidal volumes delivered several times per second, and previous small studies have suggested reduces mortality in patients with ARDS. In this multicenter Canadian/Saudi trial, the researchers set out to randomize 1200 patients with hypoxemia and radiographic opacities due to moderate or severe ARDS to either HFOV or standard ventilator settings using pressure control mode. All patients were between 16 and 85 years of age (mean age = 55 years), approximately half were septic, and slightly more than half had pneumonia. Groups were balanced at the start of the study. Patients were followed up until hospital discharge or death, and all-cause mortality during the hospitalization was the primary outcome. An interim analysis found a significant increase in mortality in the HFOV group, so the trial was terminated (at the time of termination, 548 patients had been randomized). At that time, mortality was 47% in the HFOV group and 35% in the standard ventilation group (absolute risk increase = 12%; number needed to treat to harm = 8; hazard ratio = 1.33; 95% CI, 1.09 - 1.64). Patients assigned to HFOV also had a longer mean duration of ventilation (2.5 vs 1.9 days; P = .003). Another large randomized trial (N = 795) in the same issue of this journal found similar results, with no difference in 30-day mortality in a comparison of HFOV with standard ventilation (N Engl J Med 2013;368:806-13).


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