Passport 12/Passport 8 Operator’s Manual 11-1
11 Monitoring SpO
2
11.1 Introduction
SpO
2
monitoring is a non-invasive technique used to measure the amount of oxygenated haemoglobin and pulse rate
by measuring the absorption of selected wavelengths of light. The light generated in the probe passes through the
tissue and is converted into electrical signals by the photodetector in the probe. The SpO
2
module processes the
electrical signal and displays a waveform and digital values for SpO
2
and pulse rate.
This device is calibrated to display functional oxygen saturation. It provides the following measurements:
1. Pleth waveform (Pleth): visual indication of patient’s pulse. The waveform is not normalized.
2. Oxygen saturation of arterial blood (SpO
2
): percentage of oxygenated hemoglobin in relation to the sum of
oxyhemoglobin and deoxyhemoglobin.
3. Perfusion index (PI): gives the numerical value for the pulsatile portion of the measured signal caused by arterial
pulsation. PI is an indicator of the pulsatile strength. You can also use it to assess the quality of SpO
2
measurement.
Above 1 is optimal
Between 0.3 and 1 is acceptable
Below 0.3 indicates low perfusion;. When PI is below 0.3, a question mark (?) is displayed to the right of the
SpO
2
value, indicating that the SpO
2
value may be inaccurate. R eposition the SpO
2
sensor or find a better site.
If low perfusion persists, choose another method to measure oxygen saturation if possible.
PI is available for Masimo SpO
2
module. For Masimo SpO
2
module, PI value can be displayed under the PR value in
larger characters if [PI Zoom] is enabled.
4. Perfusion indicator: the pulsatile portion of the measured signal caused by arterial pulsation.
5. Pulse rate (derived from the pleth wave): detected pulsations per minute.
NOTE
A functional tester or SpO
2
simulator cannot be used to assess the accuracy of a SpO
2
module or a SpO
2
sensor.
4
1
3
5
2
To Next Page
Loading...
Need help?
General
