Clinical implications of a physiologic approach to paediatric high-frequency oscillatory ventilation

Paediatric acute respiratory distress syndrome (PARDS) is a manifestation of severe, life-threatening lung injury necessitating mechanical support. However, if inappropriately set and not tailored to the respiratory system mechanics of the individual patient, mechanical support of breathing can lead to ventilator-induced lung injury. High-frequency oscillatory ventilation (HFOV) is, at least theoretically, a justifiable mode to be considered to limit lung stress and strain, especially in patients severe PARDS. However, these theoretical benefits have not been translated into improved clinical outcomes. In addition, in adult ARDS HFOV is associated with harm. However, an important question is whether the results of the exisitng randomised clinical trials confirm that HFOV is not beneficial, and its use should be discouraged, or if it is a matter of how the oscillator was used that determins patient outcomes. Currently, HFOV is mainly used as a rescue mode of ventilation and titration of HFOV settings is mainly based on manufacturer’s recommendations, personal beliefs, and institutional preferences. We propose in this perspective a physiology-driven, open-lung strategy for paediatric HFOV for patients with moderate to severe lung disease to avoid injurious conventional ventilation settings, making use of lung recruitment manoeuvres, and setting high oscillatory frequencies to deliver the smallest distal pressure amplitudes. This approach has been shown feasible and safe in children, but needs evaluateion for efficacy. Future investigations should also explore HFOV weaning and monitoring during HFOV.