Should High-Frequency Ventilation in the Adult Be Abandoned?

Abstract

SummaryHigh-frequency oscillatory ventilation (HFOV) can improve ventilation-perfusion matching without excessive alveolar tidal stretching or collapse-reopening phenomenon. This is an attractive feature in the ventilation of patients with ARDS. However, two recent large multi-center trials of HFOV failed to show benefits in this patient population. The following review addresses whether, in view of these trails, HFOV should be abandoned in the adult population? Key words: acute respiratory failure; high-frequency oscillatory ventilation. [Respir Care 2016;61(6):791-800.

The Role of Rescue Therapies in the Treatment of Severe ARDS

“…HFOV should not be used routinely in place of conventional lung-protective ventilation, and it should be reserved as a rescue therapy for those patients with refractory hypoxemia and in selected cases of severe ARDS. 54 The assessment of transpulmonary pressure by measuring esophageal pressure may represent a valid strategy to adopt more physiological P aw , reducing the risk of further lung injury and leading to maximal lung recruitment and minimal overdistention. 55 The EPOCH Study (Clinical Trials.gov NCT02342756) is using this approach to adjust PEEP during conventional mechanical ventilation and P aw during HFOV.…”

Why All the Shots at Airway Pressure Release Ventilation When Conventional Ventilation Doesn't Have Consensus?

“…This last point is particularly important in complex interventions like mechanical ventilation where potential settings and management strategies can be quite variable." 3 Miller et al 1 state that "APRV is not an on-off switch … as a consequence, interpreting trials and making recommendations about APRV problematic." However, one of the authors in 2016 stated the following about high-frequency oscillatory ventilation (HFOV), "[HFOV] is certainly not an onoff switch and involves not only numerous specific ventilator adjustments but also adjustments in other aspects of management (eg, fluids, pressors) that clearly can impact results.…”

“…To draw the conclusion that HFOV managed differently in different patients is necessarily harmful seems excessive." 3 The question now becomes, why do the authors differ in their interpretation of APRV and HFOV not serving as an on-off switch? The evidence reported to date on APRV shows that it is no worse than conventional ventilation in the limited studies that compared the 2 methods, in contrast with a large clinical trial that demonstrated poor outcomes with HFOV.…”

“…The evidence reported to date on APRV shows that it is no worse than conventional ventilation in the limited studies that compared the 2 methods, in contrast with a large clinical trial that demonstrated poor outcomes with HFOV. 3,4 When you look at the authors' 1 reported survey responses on the P high setting, a patient with conventional settings and measurements of PEEP 15 cm H 2 O, P pl 28 cm H 2 O, and peak inspiratory pressure 30 cm H 2 O, the patient would have a mean of approximately 20 cm H 2 O. This would mean that 79% of the survey respondents would set their P high at 25-28 cm H 2 O.…”

Quantifying Regional Lung Deformation Using Four-Dimensional Computed Tomography: A Comparison of Conventional and Oscillatory Ventilation

“…In some instances, high-frequency oscillatory ventilation (HFOV) has been proposed as a rescue treatment for refractory hypoxemia in ARDS, given its theoretically ideal qualities for lung-protection: small tidal volumes that mitigate the risk of dynamic strain injury (i.e., volutrauma), and high mean airway pressures that prevent cyclic recruitment/derecruitment (i.e., atelectrauma) (Sklar et al, 2017). Despite an extensive history of scientific and clinical research over several decades, optimal strategies for HFOV initiation and management remain a subject of controversy (Malhotra and Drazen, 2013;Kneyber and Markhorst, 2016;Nguyen et al, 2016). As it is currently delivered, HFOV may not be an appropriate ventilatory modality in many patients with ARDS for several reasons.…”