Does high-frequency ventilation offer benefits over conventional ventilation in adult patients with acute respiratory distress syndrome?
High-frequency ventilation is the application of mechanical ventilation with a respiratory rate > 100 breaths/min. High-frequency oscillatory ventilation (HFOV) is the form of high-frequency ventilation most widely used in adult critical care. The principles of lung-protective ventilation have matured in parallel with the technology for HFOV. The 2 basic principles of lung-protective ventilation are the use of small tidal volume and maintenance of adequate alveolar recruitment. Research in animal models and humans demonstrate that HFOV can support gas exchange with much smaller tidal volume than can be achieved with conventional ventilation. HFOV also provides more effective lung recruitment than conventional mechanical ventilation. However, at present, evidence is lacking that survival in adults with acute respiratory distress syndrome is improved by HFOV. Although HFOV may improve P(aO(2)) in some patients, this improvement is often transitory. Available evidence does not support tha