DARAY V460S Series, User Manual & Installation Manual

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The V460S has the added functionality of an SpO
2
Plethysmogram sensor. This measurement is
employed to determine the oxygen saturation of haemoglobin in the arterial blood.
If, for example; 97% haemoglobin molecules in the red blood cells are combined with oxygen, then
the blood has an SpO
2
rate of 97%. With a Plethysmogram signal you can also derive a pulse rate
signal and the plethysmograph waveform. ( NOTE - An SpO
2
waveform is not proportional to the
pulse volume).
The SpO2 measurement works by using a continuous, non-invasive light source that compares the
absorption spectra of unsaturated haemoglobin versus Oxyhemoglobin. It measures how much
light, sent from a light source on one side of the sensor, is transmitted through the patient tissue
(such as a finger or an ear) to a receiver on the other side (this process is called the
spectrophotometer principle).
The sensors measurement wavelengths are nominally 660nm for the Red LED and 940nm for the
Infrared LED. Maximum optical power output for the LED is 4mW.
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, this pulsation is what provides a waveform and the pulse rate signal.
The SpO
2
value and the PLETH waveforms are displayed on the main screen.
The update period for the SpO2 should be less than 5 seconds*, please read the measured value
when the waveform on screen is equal and steady. The measured value is the optimal value.
*Note the 5 second update is dependent on several factors such as placement and patient
movement.
Warnings
Pre-Use
Checks Check the device for any damage or cuts in the wiring before monitoring. Do
not use the SpO2 sensor once the monitor or the sensor is found damaged.
Electrosurgery be careful when conducting electrosurgical procedures, do not get the ES
equipment wire tangled with the SpO2 wire
Placement Do not put the sensor on extremities that also have arterial catheters or
venous syringes.
Do not perform SpO
2
measuring or NIBP measuring on the same arm at one
time, because obstruction of blood flow during NIBP measuring may
adversely affect the reading of the SpO
2
value.
As with any medical equipment, carefully route patient cabling to reduce
the possibility of patient entanglement or strangulation. Cables of electrical
surgical equipment should not be wound around that of the SpO2 sensor
Don’t use the monitor to measure patients whose pulse rate is lower than
30bpm, this may cause incorrect results.
Make sure no contamination or scar exists in the site where the sensor is
placed. Otherwise, the measured result may be incorrect because the signal
received by the sensor can be affected.
Damage Do not use the SpO
2
sensor if the package or the sensor is found damaged.
Instead, you should contact your supplier to discuss the best course of
action.
Prolonged Use Prolonged and continuous monitoring may increase the likelihood of
unexpected changes in the dermal condition of your patient, such as
abnormal sensitivity, erubescence, vesicle, repressive putrescence, etc. It is
especially important to check the sensor placement of neonatal patients or
those with poor perfusion or immature dermogram’s by light collimation.
To properly attach the sensor you should always take into consideration
changes in the skin. Check the sensor placement every 2/3 hours and move it
when the skin deteriorates. More frequent examinations may be required for
different patients.
Remove the SpO2
sensor from the patient after measurement
When used on different patients, the monitor is prone to cross
contamination, this should be prevented and controlled by the user.
Disinfection is recommended before using the SpO2 sensor on other patients.