High-frequency oscillatory ventilation (HFOV)

High-frequency oscillatory ventilation (HFOV) is increasingly utilized for adult patients with ARDS who remain hypoxemic despite optimal settings of conventional mechanical ventilation (CMV).

HFOV maintains a constant mean airway pressure and delivers very small tidal volumes (1-3 ml/kg) at very high respiratory rates (frequency range up to 10 Hz).

Potential advantages to HFOV over CMV include greater alveolar recruitment, prevention of atelectrauma, and limiting excess alveolar distension (i.e. volutrauma).
Studies on HFOV in adults are not as numerous as those in neonates. As a result, optimal timing for initiation of HFOV is unclear.
Nevertheless, some recommend considering HFOV for patients who persistently need an F_iO₂ > 60% with at least 10 cm H₂O of PEEP on CMV.
Due to the ventilator settings, patients receiving HFOV often require significant sedation and often neuromuscular blockade.

References
Ip T, Mehta S. The role of high-frequency oscillatory ventilation in the treatment of acute respiratory failure in adults. Curr Opin Crit Care 2012; 18:70-9.

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