Mindray iMEC8 Vet, Руководство оператора

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11-1
11
Monitoring SpO
2
11.1 Introduction
SpO
2
monitoring is a non-invasive technique used to measure the amount of oxygenated hemoglobin 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 four 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; reposition 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 the Mindray SpO
2
module or the Masimo SpO
2
module.
4. Perfusion indicator: the pulsatile portion of the measured signal caused by arterial pulsation.
5. Pulse rate (derived from pleth wave): detected pulsations per minute.
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