Philips BiPAP A40 - 2.2.1 AVAPS

BiPAP A40 user manual
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AVAPS-AE A novel Bi-level therapy mode that provides an automatically adjusting EPAP,
Pressure Support, and back-up breath rate.
In AVAPS-AE mode, the device monitors the patient’s upper airway resistance and
automatically adjusts the delivered EPAP required to maintain a patent airway.
In this mode, the AVAPS feature is always enabled. This allows the device to
automatically adjust Pressure Support to maintain a target tidal volume. (Refer to
the description of AVAPS in Section 2.2, Therapy Features.) The required Pressure
Support is delivered above the automatic EPAP setting.
Additionally, when the Breath Rate is set to Auto, the device will automatically adjust
the back-up breath rate based on the patient’s spontaneous respiratory rate.
2.2 Therapy Features
If prescribed for you, the device provides the following therapy features.
2.2.1 AVAPS
Average Volume Assured Pressure Support (AVAPS) is a feature available in the S, S/T, PC, and T
modes. (In AVAPS-AE mode, the AVAPS feature is always enabled.) AVAPS helps patients maintain
a tidal volume (VT) equal to or greater than the target tidal volume (Tidal Volume setting) by
automatically controlling the pressure support (PS) provided to the patient. The AVAPS feature
adjusts PS by varying the IPAP level between the IPAP Min and IPAP Max settings (or Pressure
Support Min and Pressure Support Max in AVAPS-AE mode). AVAPS will retain the learned PS for the
patient so that each time therapy is started the PS will start at the learned PS.
The AVAPS algorithm in the BiPAP A40 contains an improvement to more accurately achieve
and maintain the target tidal volume. The muscle eort of a spontaneous breath typically results
in a larger tidal volume than a machine breath delivered at the same pressure. The new AVAPS
algorithm will adjust the pressure slightly on machine delivered breaths to compensate for this
dierence, and throughout the night, the algorithm will “learn” the correct amount of pressure
adjustment to apply to machine triggered breaths.
If IPAP Max is reached and the target tidal volume is not achieved, the Low Tidal Volume alarm
activates (if enabled).