Gima OXY-5, Use And Maintenance Book

Page: 13 / 76

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2.3 Environment Requirements
Temperature:
Operating Temperature: 10°C ~40°C
Storage Temperature: -20°C~55°C
Humidity:
Operating Humidity: 35%~80%
Storage Humidity: 10%~100%
Atmospheric pressure:
Operating Pressure: 70kPa~106kPa
Storage Pressure: 50kPa~106kPa
2.4 Principle of Measurement
The measurement of pulse oximeter is that it uses a multi-functional oxyhemoglobinometer
to transmit some narrow spectrum light bands through blood samples and to measure
attenuation of spectrum with different wavelengths according wo the characteristic that
RHb, O
2
HB, Met Hb and COHb absorb the light of different wavelength, thereby determining
O
2
Hb saturation of different fractions. O
2
Hb saturation is called “fractional” O
2
Hb saturation.
Fractional O
2
Hb saturation = [O
2
Hb / (RHb + O
2
Hb + Met Hb + COHb)] × 100
Oppositely, pulse oxygen oximeter measures functional O
2
Hb saturation:
Functional O
2
Hb saturation = [O
2
Hb / (RHb + O
2
Hb)] × 100
Present SpO
2
oximeter transmits light of two wavelengths only, red light (wavelength 660
nm) and infrared (wavelength 940 nm), to differentiate HbO
2
from HbR. One side of the
sensor contains two LEDs, and the other side contains a photoelectric detector. SpO
2
oximeter measures HbO
2
saturation in the blood by the light plethysmograph when the pulse
beats. The result is quite precise when HbO
2
saturation is over 70% ~ 95%.
2.5 Caution
A. The finger should be placed properly (see the attached illustration of this manual), or else
it may cause inaccurate measurement.
B. The SpO
2
sensor and photoelectric receiving tube should be arranged in a way with the
subject’ s arteriole in a position there
in
between
.
C. The SpO
2
sensor should not be used at a location or limb tied with arterial canal or blood
pressure cuff or receiving intravenous injection.
D. Do not fix the SpO
2
sensor with adhesive or else it may result in venous pulsation and
inaccurate measure of SpO
2
.
E. Make sure the optical path is free from any optical obstacles like rubberized fabric.
F. Excessive ambient light may affect the measuring result. It includes fluorescent lamp, dual
ruby light, infrared heater, direct sunlight and etc.
G. Strenuous action of the subject or extreme electrosurgical interference may also affect
the accuracy.
H. Testee can not use enamel or other makeup on the finger.
ENGLISH