DARAY V409, Руководство пользователя, Страница: 8 / 17

8
6 Operation
Press the power button to turn on the device. The OED screen appears display. If there is no
finger inserted into the device, the device will automatically shut down in 8 seconds to save
power.
NOTE
The device is powered by batteries. The batteries must be installed in the device before
powering on. If the battery power is insufficient, the device may fail to be turned on. At
this moment, the batteries should be replaced with new ones.
7. SpO2 Measurement
Measurement principle
SpO2 plethysmogram measurement is employed to determine the oxygen saturation of
hemoglobin in the arterial blood. The SpO2/PLETH parameter can also provide a pulse rate
signal, pulse strength and a plethysmogram wave. How the SpO2 I PLETH Parameter Works

Arterial oxygen saturation is measured by a method called pulse oximetry. It is a
continuous, non-invasive method based on the different spectra absorption of hemoglobin
and oxyhemogiobin (called spectrophotometer principle). It measures how much light,
sent from light sources on one side of the sensor, is transmitted through patient tissue
(such as a finger or a toe), to a receiver on the other side.
 The sensor measurement wavelengths are nominally 660nm for the Red

LED and 940nm for Infrared LED.
Maximum optical power output for LED is 4 mW.

The amount of light transmitted depends on many factors, most of which are constant.
However, one of these factors, the blood flow in the arteries, varies with time, because it
is pulsating. By measuring the light absorption during a pulsation, it is possible to derive
the oxygen saturation of the arterial blood. Detecting the pulsation gives a PLETH
waveform, pulse rate signal and pulse strength.
 The SpO2 value, PR value and pulse strength can be displayed on the screen.
 SpO2 is a non-invasive measurement of the functional oxygen saturation.

The light sources and the receiver of the sensor are laid in the two rubber cushions of the
device respectively.
Measurement steps
 Press (5) in the Figure3-1 and open the clip.

Insert the patient's finger into the rubber cushions of the clip, make sure the finger is in
the right position as shown in figure 6-1, and then clip the finger.

Press the power button on the front panel to turn on the device.

Using first finger, middle finger or ring finger when doing test.

Do not shake the finger and keep the patient at ease during the process.

The readings will be displayed on the LED screen momentarily.
Figure 6-1 Put Finger Into the correct position