User's Manual

4-25

4.5.8

Oxygen Monitoring. This parameter is part of the EtCO2/Agents module. That is, it uses the

exhaust air from the EtCO2/Agents module as its imput and its air flow is controlled by the pneumatic

hardware in the EtCO2/Agents hardware module. The O2 value is displayed in the Anesthetic Agents

Display (See Figure 4-17).

a. Oxygen Module Calibration. The O2 module is calibrated automatically upon

power-up (as described in the NOTE above). Thereafter, is calibrated everytime an O2

CAL is initiated by the user (See the GAS CAL menu (SETUPS/SERVICE(BIO-

MED)/GAS CAL) for further information). The operator is prompted that an O2

calibration is required if O2 remains above 22% for 12 hours and, since O2 calibration

requires one (1) minute, the operator may reject the calibration request by answering

NO to the YES/NO prompt. If NO is selected the operator is then prompted every 30

minutes until the O2 calibration is initiated by a YES response. Calibration is done

based on the assumption that the ambient O2 concentration, sensed at the EtCO2

Zeroing Port, is 20.9% (during calibration, the patient GAS Input Port must not be

connected to an oxygen source).

b. Oxygen Sensor Replacement. The Oxygen Sensor (Invivo Part Number 9445) is

located on the rear of the WPU near the DCU mounting pole. The Oxygen Sensor has

an expected life of greater than six months with expected life inversely proportional to

changes in Oxygen Concentration, Temperature and Pressure. The Oxygen Sensor

begins aging immediately upon the opening of the package and should, therefore, not

be opened until ready for use. The Oxygen Sensor should be replaced periodically as

part of routine maintenance. This monitor cannot be connected to the scavenge gas

system without the Oxygen Sensor installed, never operate without the monitor

connected to the scavenge gas system. Always operate the monitor with the Oxygen

Sensor installed.

(1) Oxygen Sensor Replacement Instructions. Replace the Oxygen Sensor as

follows:

(a) Unplug the adapter cable from the Oxygen Sensor.

(b) Unscrew the Oxygen Sensor by turning it counterclockwise until it

comes free.

(d) Screw Oxygen Sensor into threaded port on Adaptor Subassembly.

(e) Plug adapter cable assembly into the Oxygen Sensor.

READJUSTING CO2

ZERO

Message flashing red. Occurs during CO2/Anesthesia

Gas Sensor zeroing operation.

REPLACE O2 SENSOR The Oxygen Sensor is bad and must be replaced.

NOTE

When the Agents parameter is turned on the O2 sensor is automatically calibrated during initial

warm up of the EtCO2/Agent Module. During this time the patient GAS input port must not be

connected to an oxygen source as the monitor requires 20.9% Oxygen (room air) for automatic

calibration.