Mindray WATO EX-55, Service Manual

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4-11
4.2.1.1 Check Volume Control Ventilation (VCV)
NOTE
z
VCV is the standard ventilation mode of the anesthesia machine and also the most
basic mechanical ventilation mode.
To check VCV:
1. Make sure that the supply pressure is normal and that the tubes in the breathing circuit
are correctly connected as required for mechanical ventilation. Connect a 2 L bag, which
is used as the test lung, to the Y piece in the patient circuit.
2. Set the bag/mechanical ventilation switch to the mechanical ventilation position.
3. Select VCV as the ventilation mode.
4. Adjust total amount of fresh gas to 0.5 L/min.
5. Set the following combinations of TV and Rate respectively: 300 ml and 15 BPM, 600
ml and 15 BPM, 900 ml and 15 BPM, 1200 ml and 15 BPM. Set others to the defaults.
Record the displayed TVe and Ppeak values, and the peak pressure reading on the
airway pressure gauge in each setting stabilized status.
6. Judge if the above measured data meet the following conditions:
‹ TV control and measurement are normal: the displayed TVe value should be within
the range of TV setting X (1±10%) ml.
‹
Circuit leak is within the acceptable range: the folding bag can reach the top of the
bellows housing each time and the lowest graduation on the bellows housing which
the bag falls to each time corresponds to approximately TV setting.
‹ Pressure measurement is normal: the Ppeak measured value is close to the peak
pressure reading on the airway pressure gauge. The error should not exceed 2
cmH2O.
‹ No other ventilation failure occurs: the Paw and flow waveforms are displayed
normally and no technical alarms occur.
If the above test requirements are not met, perform subsequent checks and do the test again.
NOTE
z
If any errors are detected during VCV test, perform troubleshooting as per
5Troubleshooting and do the test again until the system is normal.