GE iVent 201 Series User's Reference Manual page 148

Figure 128: Adaptive Bi-Level Mode
The Vte display shows the estimated Tidal Volume delivered to the patient
calculated using the measured flow leak during EPAP. An estimated Leak is
shown below the Tidal Volume field of the display.
The Leak Estimate value is measured in lpm (See Figure 129)
Figure 129: Leak Estimated Value in LPM
In SW version 19.18.01 estimated leak in adaptive Bi-Level mode is
presented in % (See Figure 130). Estimates Vti/Vte (Inhale/Exhale tidal volume
ratio) are disregarded at leaks above 40 Liters/minute.
Figure 130: % Leak Estimated Value as Shown in Version 19.18.01
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