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Ohmeda Modulus 2 Checkout Procedure

Ohmeda Modulus 2 Checkout Procedure

This checkout, or a reasonable equivalent, should be conducted before administration of anesthesia. These recommendations are only valid for an anesthesia system that conforms to current and relevant standards and includes an ascending bellows ventilator and at least the following monitors: capnograph, pulse oximeter, oxygen analyzer, respiratory volume monitor (spirometer) and breathing system pressure monitor with high and low pressure alarms. This is a guideline which users are encouraged to modify to accommodate differences in equipment design and variations in local clinical practice. Such local modifications should have appropriate peer review. Users should refer to the operations manual for procedures and precautions.

Emergency Ventilation Equipment
1. Verify Backup Ventilation Equipment is available & Functioning

High Pressure System
2. Check Oxygen Cylinder Supply
a. Open O2 cylinder and verify at least half full (about 1000 psi).
b. Close cylinder.

3. Check Central Pipeline Supplies
a. Check that hoses are connected and pipeline gauges read about 50 psi.

Low Pressure System
4. Check Initial Status of Low Pressure System
a. Close flow control valves and turn vaporizers off.
b. Check fill level and tighten vaporizers' filler caps.

5. Perform Leak Check of Machine Low Pressure System
a. Verify that the machine master switch and flow control valves are OFF.
b. Attach "suction Bulb" to common (fresh) gas outlet.
c. Squeeze bulb repeatedly until fully collapsed.
d. Verify bulb stays fully collapsed for at least 10 seconds.
e. Open one vaporizer at a time and repeat 'c' and 'd' as above.
f. Remove suction bulb, and reconnect fresh gas hose.

6. Turn On Machine Master Switch
and all other necessary electrical equipment.

7. Test Flowmeters
a. Adjust flow of all gases through their full range, checking for smooth operation of floats and undamaged flowtubes.
b. attempt to create a hypoxic O2/N2O mixture and verify correct changes in flow and/or alarm.

Scavenging System
8. Adjust and check Scavenging system
a. Ensure proper connections between the scavenging system and both APL (pop-off) valve and ventilator relief valve.
b. Adjust waste gas vacuum (if possible).
c. Fully open APL valve and occlude Y-piece.
d. With minimum O2 flow, allow scavenger reservoir bag to collapse completely and verify that absorber pressure gauge reads above zero.
e. With the O2 flush activated, allow the scavenger reservoir bag to distend fully, and then verify that absorber pressure gauge reads < 10 cm H2O.

Breathing System
9. Calibrate O2 Monitor
a. Ensure monitor reads 21% in room air.
b. Verify low O2 alarm is enabled and functioning.
c. Reinstall sensor in circuit and flush breathing system with O2.
d. Verify that monitor now reads greater than 90%.

10. Check Initial Status of Breathing System
a. Set selector switch to "Bag" mode.
b. Check that breathing circuit is complete, undamaged and unobstructed.
c. Verify that CO2 absorbent is adequate.
d. Install breathing circuit accessory equipment (e.g. humidifier, PEEP valve) to be used during the case.

11. Perform Leak Check of the Breathing System
a. Set all gas flows to zero (or minimum).
b. Close APL (pop-off) valve and occlude Y-piece.
c. Pressurize breathing system to about 30 cm H2O with O2 flush.
d. Ensure that pressure remains fixed for at least 10 seconds.
e. Open APL (Pop-off) valve and ensure that pressure decreases.

Manual & Automated Ventilation Systems
12. Test Ventilation Systems and Unidirectional Valves
a. Place a second breathing bag on Y-piece.
b. Set appropriate ventilator parameters for next patient.
c. Switch to automatic ventilation (Ventilator) mode.
d. Turn Ventilator ON and fill bellows and breathing bag with O2 flush.
e. Set O2 flow to minimum, other gas flows to zero.
f. Verify that during inspiration bellows delivers appropriate tidal volume and that during expiration bellows fill completely.
g. Set fresh gas flow to about 5 L/min.
h. Verify that the ventilator bellows and simulated lungs fill and empty appropriately without sustained pressure at end of expiration.
i. Check for proper action of unidirectional valves.
j. Exercise breathing circuit accessories to ensure proper function.
k. Turn ventilator OFF and switch to manual ventilation (Bag/APL) mode.
l. Ventilate manually and assure inflation and deflation of artificial lungs and appropriate feel of system resistance and compliance.
m. Remove second breathing bag from y-piece.

13. Check, Calibrate and/or Set Alarm Limits of all Monitors
· Capnometer
· Oxygen Analyzer
· Pulse Oximeter
· Respiratory Volume Monitor
· Pressure Monitor with High and low Airway Alarms.

Final Position
14. Check Final Status of Machine
a. All flowmeters to zero
b. Patient suction level adequate
c. Breathing system ready to use
d. Selector switch to "bag"
e. Vaporizers off
f. APL valve open

*If an anesthesia provider uses the same machine in successive cases, these steps need not be repeated or may be abbreviated after the initial checkout.

Source: Anesthesia Apparatus Checkout Recommendations, FDA, Oct. 1993, BWH 2005
Document owner: Evelyn Fan
Added to site: 4/07

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This page was last updated on 4/30/2007