3
As with all mask ventilation systems, significant leak
may occur between the mask and the patient’s
face. The leak may vary depending on such factors
as the patient’s position and sleep stage. Variation
in leak may significantly affect patient ventilation,
potentially producing profound hypoventilation or
hyperventilation. The magnitude of this effect
depends on the ventilator’s ability to compensate
for leak.
Leak or variation in the leak may cause
mistriggering of the ventilator.
Increased face-to-mask leak will reduce effective
deadspace by washing out expired gases. In a
pressure-cycled ventilator which tolerates moderate
leak, the effect may be a reduction in arterial PCO2
with no change in ventilator settings.
ADDITIONAL INFORMATION
ResMed has tinted the MIRAGE NV FULL FACE MASK
SERIES 2 blue to help you identify it as a non-
vented mask for use with active-exhaust non-
invasive ventilator systems only.
The mask has a standard female 22mm tapered
fitting (ISO5356-1) for external connection to the
ventilator.
In determining the initial ventilator settings, and in
particular the tidal volume for volume-cycled
ventilators, make appropriate allowance for mask
dead space and leak. Refer to the Mask
Characteristics section of these instructions for more
information.
Refer to the relevant ventilator system operating
instructions for detailed information concerning
connecting the mask.