11
2.2 Therapy Features
The device can provide the following therapy features.
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 (V
te
) 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 OmniLab Ad contains an improvement to more accurately achieve and maintain
the target tidal volume. The muscle effort 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 difference, 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).
WARNING: The effectiveness of the A-Flex, Bi-Flex, C-Flex, C-Flex+ or AVAPS therapy features or the autoSV
mode has not been established for pediatric patients at this time.
AVAPS Rate
The AVAPS Rate setting allows you to adjust the maximum rate at which the pressure support automatically
changes to achieve the target tidal volume. The actual rate may be less than this maximum setting depending
on how far the current estimated tidal volume is from the target tidal volume. A higher rate allows the AVAPS
algorithm to change pressure support faster to meet the target tidal volume. It can be set from 0.5 cm H
2
O per
minute to 5.0 cm H
2
O per minute in increments of 0.5 cm H
2
O per minute.
C-Flex Comfort Feature
The device provides the C-Flex feature in CPAP and Auto-CPAP
modes. The C-Flex attribute adjusts therapy by providing pressure
relief during active exhalation (the beginning part of exhalation). In
the diagram, the bold lines represent C-Flex in comparison to the
dashed line representing normal CPAP therapy. C-Flex levels of 1,
2, or 3 progressively reflect increased pressure relief that will take
place at the end of inspiration and at the beginning of expiration.
WARNING: The effectiveness of the A-Flex, Bi-Flex, C-Flex,
C-Flex+ or AVAPS therapy features or the autoSV mode has
not been established for pediatric patients at this time.
CPAP
Time
1
2
3
C-Flex