Gima 34285, Use And Maintenance Book

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calculated by the following method:
SpO
2
= HbO2/ (HbO2 +Hb)×100%
HbO
2
are the oxyhemoglobins (oxygenized hemoglobin), Hb are those
hemoglobins which release oxygen.
2. Principle of Measurement
Based on Lamber-Beer law, the light absorbance of a given substance
is directly proportional with its density or concentration. When the light
with certain wavelength emits on human tissue, the measured intensity
of light after absorption, reflecting and attenuation in tissue can reflect
the structure character of the tissue by which the light passes. Due to
that oxygenated hemoglobin (HbO
2
) and deoxygenated hemoglobin
(Hb) have different absorption character in the spectrum range from red
to infrared light (600nm~1000nm wavelength), by using these charac-
teristics, SpO
2
can be determined. SpO
2
measured by this oximeter is
the functional oxygen saturation - a percentage of the hemoglobin that
can transport oxygen.
In contrast, hemoximeters report fractional oxygen saturation - a per-
centage of all measured hemoglobin, including dysfunctional hemoglo-
bin, such as carboxyhemoglobin or metahemoglobin.
Clinical application of pulse oximeters: SpO
2
is an important physiologi-
cal parameter to reflect the respiration and ventilation function, so SpO
2
monitoring used in treatment has become more popular. (For example,
such as monitoring patients with serious respiratory disease, patients
under anesthesia during operation and premature and neonatal infants)
The status of SpO
2
can be determined in timely manner by measure-
ment and will allow finding the hypoxemia patient earlier, thereby pre-
venting or reducing accidental death caused by hypoxia effectively.
3. Factors affecting SpO
2
measuring accuracy
(interference reason)
• Intravascular dyes such as indocyanine green or methylene blue.
• Exposure to excessive illumination, such as surgical lamps, bilirubin
lamps, fluorescent lights, infrared heating lamps, or direct sunlight.
• Vascular dyes or external used color-up product such as nail enamel
or color skin care.
• Excessive patient movement.
• Placement of a sensor on an extremity with a blood pressure cuff,
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