SpO2 Monitoring
Note
If the sensor cannot be positioned accurately to the part to be measured, it may result
in inaccurate SpO2 reading, or even that the SpO2 cannot be measured because no
pulse is detected. If this is true, you must position the sensor again.
The excessive patient movement may result in inaccurate reading. In this situation, you
must keep the patient quiet or change the part for monitoring to reduce the adverse
influence of excessive movement.
^-IA Warning ZIA
In the process of extended and continuous monitoring, you should check the
peripheral circulation and the skin every 2 hours. If any unfavorable changes take
place, you should change the measured position in time.
In the process of extended and continuous monitoring, you should periodically check
the position of the sensor. In case that the position of the sensor moves during
monitoring, the measurement accuracy may be affected.
12.4 Limitations for Measurement
Measurement Limitations
In operation, the accuracy of oximetry readings can be affected by:
High-frequency electrical noise, including noise created by the host system, or
noise from external sources, such as electrosurgical apparatus connected to the
system.
Do not use oximeters and oximetry sensors during magnetic resonance imaging
(MRI) scanning. Induced current could potentially cause burns.
Intravascular dye injections
Excessive patient movement
External light radiation
Improper sensor installation or incorrect contact position of the patient
Sensor temperature (optimal temperature between 28° C and 42° C)
Placement of the sensor on an extremity that has a blood pressure cuff, arterial
catheter, or intravascular line.
Significant concentrations of dysfunctional hemoglobin, such as
carboxyhemoglobin and methemoglobin.
SpO2 too low
Bad circular injection of the part being measured
Shock, anemia, low temperature and application of vasomotor may all cause the
arterial blood flow to reduce and hence make the measurement impossible.
The absorption of oxyhemoglobin (HbO2) and deoxyhemoglobin to the light of
special wavelength may also affect SpO2 measurement. If there exist other objects
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