Vital Signs Monitor User Manual Monitoring SpO
2
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2 The pulse rate accuracy is obtained by comparison to the pulse rate generated with
an arterial oxygen simulator (also an electronic pulse simulator).
3 During monitoring, if the monitor's reading differs significantly from the patient's
physiological condition, it indicates that the signal may be disturbed, resulting in an
inaccurate reading. In this case, the artifact can disguise as a similar reading,
causing the monitor to fail to send an alarm. In order to ensure reliable monitoring, it
is necessary to regularly check whether the sensor is wearing properly and the signal
quality is good.
11.6 SpO
2
Alarm Delay
There is a delay between a physiological event at the measurement site and the corresponding
alarm at the monitor. This delay has two components:
1.
The time between the occurrence of the physiological event and when this event is
represented by the displayed numerical values. This delay depends on the algorithmic
processing time and the sensitivity setting. The lower the sensitivity configured, the longer
the time needed until the numerical values reflect the physiological event.
2.
The time between the displayed numerical values exceeding an alarm limit and the alarm
indication on the monitor. This delay is the combination of the configured alarm delay time
plus the general system delay time.
11.7 Perfusion Index (PI)*
*
Only applicable to the EDAN SpO
2
module.
PI is a numeric value indicating perfusion level. It reflects the perfusion level at the monitoring
site.
As the measurement of SpO
2
is based on the pulsation caused by the blood flow through the
vessel, PI is in relation to the strength of the pulse. Also, you can use PI as a signal quality
indicator for the measurement of SpO
2
.
PI is indicated by a value ranging from 0 to 10. The bigger the value is, the better the perfusion
and the signal quality will be. The perfusion level and the signal quality are at their maximum
when the value reaches 10. When PI is below 2, it indicates the low perfusion and the poor signal
quality at the monitoring site; you need to reposition the sensor or find a better site.
The PI value will be displayed in the SpO
2
parameter area.
11.8 Setting Pitch Tone
If tone modulation is on, the PR sound lowers when the SpO
2
level drops. In the
SpO
2
Setup
menu, select pitch tone to toggle between
On
and
Off
. The lower SpO
2
value is, the lower the
frequency of Pitch tone is.