Comparing surrogates of oxygenation and ventilation between airway pressure release ventilation and biphasic airway pressure in a mechanical model of adult respiratory distress syndrome

Randomized Feasibility Trial of a Low Tidal Volume-Airway Pressure Release Ventilation Protocol Compared With Traditional Airway Pressure Release Ventilation and Volume Control Ventilation Protocols

“…2 ) which supports concerns about potential harms ( 28 , 61 , 63 ). The P aw in APRV is often considered to be similar to the intrinsic PEEP required by the patient to achieve the critical opening pressure on the hysteresis curve but often it approaches P high ( 28 , 64 , 65 ). In our study, both APRV protocols demonstrated numerically higher P aw compared with VC-LTV.…”

Airway Pressure Release Ventilation: A Review of the Evidence, Theoretical Benefits, and Alternative Titration Strategies

“…However, this calculation of PEEPi may be inaccurate, often underestimating the PEEPi as seen in a previous lung simulator model. 64 Thus, following this initial setting of T low based on the time constant, the operator following the Zhou protocol would further titrate T low to maintain an EEFR:PEFR ratio of 0.5 as previously discussed. Further titrations of T low could be accomplished by viewing the flow-time curve on the ventilator to achieve an angle of expiratory deceleration of 45°.…”

APRV for ARDS: the complexities of a mode and how it affects even the best trials

“…In recent years, very detailed studies (23,24) examining the effects of setting T low on APRV demonstrated that de-recruitment occurs very rapidly in animal lung models of ARDS. Actually, to maintain recruitment of the injured alveoli population requires a very short T low , less than 0.2 sec [which, by the way, not many ventilators can achieve (25) ]. Thus, APRV remains a mode with a potential to expose the lung to high transpulmonary pressures, cyclic de-recruitment and potentially high tidal volumes, along with the possibility of overconfidence in the face of improved oxygenation (26).…”