Patient Monitor User Manual CO
2
Measuring (Optional)
- 135 -
WARNING
9 The patient monitor will be damaged if the water quantity in the water trap reaches
the limit.
10 The machine will be damaged if any pipeline from the CO
2
module has been
disconnected, or the air tube/air inlet/air outlet has been plugged by water or other
materials.
NOTE:
After the Low battery alarm is activated, please do not start the CO
2
measurement, or the
monitor may be turned off for the low capacity of battery.
17.2 Monitoring Procedure
The principle of CO
2
measurement is primarily based on the fact that CO
2
molecule can absorb
4.3
μ
m infrared ray. Absorption intensity is proportional to CO
2
concentration of patient sample,
the CO
2
concentration will compute according to the detecting CO
2
absorption intensity of patient
sample. The relation between partial pressure and percentage of CO
2
concentration is given
below:
P (mmHg) = Percentage (%) × Pamp (Ambient Pressure)
LoFlo CO
2
module setup
NOTE:
You must perform a zero calibration as described in this procedure each time the ambient
temperature changes more than 10°C (for example during transport).
Figure 17-1 LoFlo CO
2
module