BT-740 Operation manual
79
P/N : 740-ENG-OPM-EUR-D03
Bistos Co., Ltd.
2018.05
10.6 Measuring influencing factors
During operation, the following factors can affect the accuracy of SpO
2
measurement:
High-frequency radio wave interference, such as interference generated by the host
system or interference from electrosurgery instrument connected to the system.
Intravenous dye.
Too frequent movement of the patient.
External light radiation.
Sensor is improperly installed or improperly in contact with the patient.
Sensor temperature.
The sensor is placed on limbs with blood pressure cuff, arterial duct or lumen tube.
Concentration of non-functional hemoglobin such as carboxyhemoglobin (COHb) and
methemoglobin (MetHb).
Shock, anemia, hypothermia, and the application of vasoconstrictor drugs may reduce the
arterial blood flow to a level that cannot be measured.
The measurement also depends on the absorption of specific wavelengths of light by
oxyhemoglobin and reduced hemoglobin. If there is any other substance that absorbs the
same wavelength, the measurement may have false or low SpO
2
values, such as: carbon
hemoglobin, methemoglobin, methylene blue, and indigo carmine.
SpO
2
probe described in Annex is recommended.
Operating environment limit: Operating temperature range: 5
～
40
℃
, Humidity
range:30%~85% (non-condensing) Atmospheric pressure: 700hPa
～
1060hPa.
10.7 Alarm setup
In “SpO
2
Setup” menu, select “Alarm Setup >>” to enter “Alarm Setup” interface, and set SpO
2
alarm switch, alarm level, upper and lower alarm limit. See 6.5 Alarm Setup for detailed setting
method.
