The “How To” of BiVent (APRV) . David Pitts II, RRT Clinical Applications Specialist, Maquet Birmingham, Alabama Sponsored by Maquet, Inc – Servo Ventilators. Objectives. Provide the definition and names for APRV Explain the four set parameters.
David Pitts II, RRT
Clinical Applications Specialist, Maquet
Sponsored by Maquet, Inc – Servo Ventilators
Increase the ventilator rate
Airway Pressure Release Ventilation
High Frequency Ventilation
Extracorporeal Life Support
To provide the lung protective ventilation supported by the ARDSnet research.
Use an “Open lung” approach.
Minimize alveolar overdistension.
Avoid repeated alveolar collapse and reexpansion.
Restore FRC through recruitment and,
Maintain FRC by creating intrinsic PEEP.
Thus, regional auto-PEEP a desirable outcome with APRVRelease Time - TPEEP
Atelectasis can develop in seconds when Paw drops below a critical value in the injured lung.(Neumann P, JAP 1998, Newmann P, AJRCCM 1998, Frawley, 2001; McCunn, Internat’l Anesth Clinics 2002).
Too long a release time would interfere with oxygenation and allow lung units to collapse.
T High/T low- 12-16 releases
T High (s) T low (s) Freq.
3.0 0.5 17
4.0 0.5 13
5.0 0.5 11
6.0 0.5 9
P high 20-30 cm H2O, according to the following chart.
T high range 4-6 sec.
PS- as indicated with special attention given to PIP.
T low = 0.5 sec and
P low = 0
Set Releases and I:E
Create releases and I:E
(On P High)
(On P High)
Spontaneous Breaths w/PS
To Increase PaO2
Add Pressure Support judiciously.
Add Pressure Support to P High in order to decrease WOB while avoiding over-distention,
P High + PS < 30 cmH2O.
APRV is a pressure-targeted mode of ventilation.
Volume delivery depends on lung compliance, airway resistance and the patient’s spontaneous effort.
APRV does not completely support CO2 elimination, but relies on spontaneous breathing