BIO-MED DEVICES IC-2A Service Manual page 24

b. Ventilator should cycle only on patient demand or when triggered by the back-
up timer.
period (after the set expiratory or back-up timer period has elapsed).
c. Set the EXPIRATORY TIME control to the "I" in IMV. Trigger the Ventilator
and let the expiratory period elapse.
Ventilator should be heard. Trigger the Ventilator again.
The exhalation valve should pressurize and a bolus of gas should be
delivered through the patient circuit. Continue to trigger the ventilator and it
should deliver unpressurized gas during each inspiration until the end of the
set expiratory period. After the next demand signal, the exhalation valve
should be pressurized and a pressurized bolus of gas should be delivered.
d. Stop triggering the Ventilator. The Back-up timer should start to cycle the
Ventilator at 4-2/3 to 6-3/4 bpm (depending upon inspiratory time).
e. Set the NORMAL/SIMV switch to NORMAL. The Ventilator should start to
cycle, delivering a pressurized bolus of gas during every inspiratory period.
MANUAL Button Operation Check
a. Connect a patient circuit and set the controls as follows:
1. FLOW RATE to 30 LPM
2. PEEP/CPAP fully clockwise
3. MAX. PRESSURE fully counterclockwise
4. INSPIRATORY EFFORT anywhere except so as to cause auto-cycling
5. CYCLE/MANUAL CPAP to MANUAL CPAP
6. OFF/ON switch to ON.
b. The Ventilator should start to cycle, but the exhalation valve will not be
pressurized. Press the MANUAL Button, and the exhalation valve should
immediately pressurize. A volume-limited bolus of gas should be delivered.
The tidal volume is the product of the inspiratory time and the flow rate.
c. Set the NORMAL/SIMV switch to SIMV. The MANUAL button should operate
as before.
Final Checkout Corrective Action
There are two possible causes of final checkout failure:
a. Incorrect line connection
b. Clogged logic circuit line.
Using the circuit schematic (Figure 2-1), check the circuit carefully. If all lines are
connected properly, the problem is a clogged line. Because of the difficulty in locating a
clogged line, factory-performed circuit replacement is recommended.
Exhalation valve should only pressurize during an inspiratory
An audible rush of gas inside the
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