EDAN iM50, Руководство пользователя

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Patient Monitor User Manual Monitoring AG
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For the Masimo AG modules, the following table is for your reference:
O
2
Range Set O
2
Range
0 to 30 vol% Low
30 to 70 vol% Med.
70 to 100 vol% High
For G7 module, the following items are available in the AG Other Setup menu: O
2
Compens.
and Vapor Compen. . The concentration of compensated gas should be set based on the current
gas concentration which is supplied for patient. As for O
2
, Make the supplied gas concentration
multiply to its volume to get the concentration. For instance, supply 100% O
2
, and its volume is
60%, then O
2
compensation is: 100%*60% = 60%. AG concentration is decided by anaesthesia
apparatus. For G7 with O
2
module, the O
2
compensation is automatic; for G7 without O
2
module,
the O
2
compensation is manual. After settings, the interface will display a dialog box: Confirm
to change the settings? And the detailed settings are displayed under the warning. Click Yes to
confirm, and click No to cancel the settings.
19.6 Effects of Humidity
The partial pressure and the volume percentage of CO
2
, N
2
O, O
2
and anesthetic agents depend on
the amount of water vapor in the measured gas. The O
2
measurement will be calibrated to show
20.8 vol% at actual ambient temperature and humidity level, instead of showing actual partial
pressure. 20.8 vol% O
2
corresponds to the actual O
2
concentration in room air with 0.7 vol% H
2
O
concentration (at 1013 hPa this equals for example 25°C and 23% RH). The measurement of CO
2
,
N
2
O, and anesthetic agents (e.g. all gases measured by the IR-bench) will always show the actual
partial pressure at the current humidity level.
In the alveoli of the patient, the breathing gas is saturated with water vapor at body temperature
(BTPS).
When the breathing gas flows through the sampling line, the gas temperature will adapt to
ambient before reaching the gas analyzer. As the NOMO section removes all condensed water, no
water will reach the ISA gas analyzer. The relative humidity of the sampled gas will be about
95%.
If CO
2
values at BTPS are required, the following equation can be used:
where:
EtCO
2
= EtCO
2
value sent from ISA [vol %]
Pamb
= Ambient pressure sent from ISA [kPa]
3.8
= Typical partial pressure of water vapor condensed between patient circuit and ISA [kPa]
EtCO
2
(BTPS) = EtCO
2
gas concentration at BTPS [vol%]
O
2
is assumed to be room air calibrated at a humidity level of 0.7 vol% H
2
O.