High frequency oscillation ventilation
Background
- High Frequency Oscillation Ventilation (HFOV) is an alternative method for mechanical ventilation in difficult to oxygenate in critically ill ARDS patients.
- Studied in patients with PaO2/FiO2 < 200
- Goal is to maintain alveolar recruitment for adequate gas exchange and decrease lung injury/atelectrauma
- Low tidal volumes based around mean airway pressures to keep alveoli open
- Delivered at high frequency
Pros
- Limits VILI
- May improve oxygenation when ECMO not available
Cons
- No difference or likely to cause harm in adult ARDS patients
- Requires heavy sedation
- Increase mean airway pressures may result in more hemodynamic instability
Procedure
Example protocol from Oscillate trial[1]
- Set FiO2 at 100%
- Recruitment maneuver of 40 cmH2O PEEP for 40 seconds
- I:E time of 1:2
- Initiate high frequency ventilation → 3-15 Hz
- VT minimized to keep pH >7.25
- Goal of 1-4 ml/Kg
- Maintain mean airway pressure of 30 cmH2O with pressure adjusted to maintain a PaO2 of 55-80 mmHg
- Reversion to standard ventilation of mean airway pressure was ≤24 cmH2O for 12 hours or anytime when ≤20 cmH2O
- Re-initiation of HFOV if FIO2 >0.4 or PEEP >14 cmH2O for >1 hour in the subsequent 48 hours
Targets
- pH>7.25
- SpO2 >88% or PaO2 >55mmHg
Oxygenation altered by:
- FiO2
- Mean airway pressures
Ventilation altered by:
- Frequency
- Decrease frequency to increase TV and ventilation
- Inspiratory time
- Amplitude of oscillations
See Also
Mechanical Ventilation Pages
- Noninvasive ventilation
- Intubation
- Mechanical ventilation (main)
- Miscellaneous
External Links
- Life in the Fast Lane - for an excellent review and tutorial
- Oscillate
- OSCAR
References
- ↑ Fergusson N, Cook D, Guyatt G. High-frequency Oscillation in Early Acute Respiratory Distress Syndrome. NEJM 2013; 368:795-805