9 Monitoring SpO2
Adjusting the Desat Limit Alarm
The Desat alarm is a high priority (red) alarm notifying you of potentially life threatening drops in
Adjust the limit.
The Pleth wave is autoscaled to maximum display size. It decreases only when the signal quality
becomes marginal. It is NOT directly proportional to the pulse volume. If you need an indication of
change in pulse volume, use the perfusion indicator.
Minimum size for reliable SpO
The perfusion numeric (
the pulsating arterial blood flow.
As pulse oximetry is based on the pulsatile nature of the signal, you can also use the perfusion numeric
as a quality indicator for the SpO
Below 0.3 is marginal; reposition the sensor or find a better site.
Perfusion Change Indicator
The perfusion change indicator is a graphic symbol which shows the change in the perfusion value,
relative to a reference value which you can set.
To set the current perfusion value as the reference value:
When a reference value has been set, the perfusion change indicator is displayed next to the perfusion
Setting SpO2/Pleth as Pulse Source
) gives a value for the pulsatile portion of the measured signal caused by
measurement. Above 1 is optimal, between 0.3-1 is acceptable.
Set Perf Ref.
to enter the
and select the correct SpO
label from the pop-up