1. To Menu

2. Anesthesia Gas Machine Checkout Procedure
Initial Steps
High-Pressure System
Low-Pressure System
Breathing System
Ventilator System
Final Status Check

3. AGM Check: Initial Steps
1.1 Calibrate the O2 monitor
1.2 Electrical Power
1.3 Quick Visual
1.4 Back-UP ventilation and Emergency Airway Equipment

4. AGM Check: Initial Steps
1.1 Calibrate O2 monitor
Turn on system master switch
Ensure monitor reads 21% with sensor in room air
Verify low O2 alarm enabled by breathing on to sensor through your surgical mask
Reinstall sensor in circuit - flush breathing system with O2 - monitor should read > 95%
cannot calibrate - faulty fuel cell
crossover between O2 supply and other gas - hospital piping, hoses or in gas machine
wrong gas in central supply / cylinder

5. AGM Check: Initial Steps
1.2 Verify Electrical Power
Unplug machine power from electrical receptacle (system master switch is still on)
Verify “Battery Power OK” message, plug in power cord and message disappears
Turn ON vital signs monitor
Battery discharged because machine previously left ON and unplugged from AC outlet
Allows gas analyzer to “warm up”

6. AGM Check: Initial Steps
1.3 Quick visual check for:
Obvious damage / Missing components
BioMed notice of Return-to-Service
Monitors are present
Circuit appears complete
Gas sampling line is attached

7. AGM Check: Initial Steps
1.4 Back-up ventilation and emergency airway equipment
Self-inflating resuscitation bag
Check that the laryngoscopes work
Bougie and stylet present
Airway device available –LMA, ETT
Check for incorrect assembly / damaged parts
Back to Menu

8. AGM Check: High Pressure System
2.1 Check central pipeline supplies
2.2 Check O2 reserve cylinder supply

9. AGM Check: High Pressure System
2.1 Check central pipeline supplies
Turn off the system master switch
Pipeline gauges read 50 – 55 PSI
Hoses are connected correctly (colours, DISS)
Disconnect O2 pipeline –gauge drops to zero
Must be off to check for leak – no minimum flow
Misconnections
Failure of central O2 supply
Line pressure fluctuations

10. AGM Check: High Pressure System
2.2 Check O2 reserve cylinder supply
Bleed O2 cylinder pressure to zero with O2 flush (O2 pipeline disconnected)
Open O2 cylinder and verify at least half full (approx psig)
Avoid reading “old” cylinder pressure
Check for wrong cylinder - double gasket defeats pin index system or pins are broken
Dust protection cap still in place

11. AGM Check: High Pressure System (cont’d)
Missing gasket; cylinder not seated in yoke properly
Cylinder valve stem loose
Unused yoke vacant with no yoke plug
Cylinder control valve leaks
Machine master switch allows leak
2.2 Check O2 reserve cylinder supply (cont’d)
Listen - no audible leak
Close cylinder – pressure gauge drops less than 100 PSI in one min
Open and close O2 flowmeter - no flow seen
Back to Menu

12. AGM Check: Low-Pressure System
3.1 Check vaporizer installation
3.2 Low pressure leak test

13. AGM Check: Low Pressure System
3.1 Check vaporizer installation
Tops of vaporizers are parallel to manifold - cannot be lifted off manifold
Vaporizers are full and fill ports closed
Verify all vaporizers OFF
Vaporizer not locked on to manifold properly
Overfilling of vaporizer

14. AGM Check: Low Pressure System
Defective suction bulb
Leak somewhere between flow control valves and common gas outlet
Extends leak test to secondary regulators
Cracked, loose, misaligned flow tubes
Loose connections – internal piping
Faulty system master switch
3.2 Perform low-pressure leak test
Do leak test with "suction bulb" device on auxiliary (fresh) gas outlet
Verify bulb stays collapsed for > 10 secs
Repeat leak test for each flowmeter (just leave them all on)
There should be no flow in the flowmeters

15. AGM Check: Low Pressure System (cont’d)
3.2 Perform low-pressure leak test
Repeat leak test for each vaporizer, one at a time – verify that the vaporizer goes through it’s dial settings then set dial to 1% conc.
Verify with each vaporizer that the other vaporizer(s) cannot be turned ON
Verify all vaporizers OFF, aux. gas outlet closed
Partially open filler/drain port
Missing vaporizer port O-ring on manifold
Faulty interlock mechanism - can turn on two vaporizers simultaneously
Vaporizer will not turn ON - interlock obstructed or vaporizer not seated properly

16. AGM Check: Low Pressure System
3.3 Test flowmeters
Put a test lung on the end of the circuit (to collect waste anesthetic gas)
Turn on the system master switch
Minimum flows are 25ml/min for O2 and zero ml/min for all other gases
Flowtubes are undamaged; floats move smoothly throughout their full range
Floats sticking - dirt, grease, static
Float stuck at top of flow tube
Stop broken off from top of flow tube and resting on float
No flow – broken tip of needle valve

17. AGM Check: Low Pressure System (cont’d)
3.3 Test flowmeters (cont’d)
O2 and N2O flow controls cannot supply hypoxic flowrates – Increase the N2O flow and watch the O2 flow increase - 1.5:.5, 3:1, 6:2 then decrease O2 flow and watch the N2O fall
Turn on Air flowmeter and ensure it works through the range and then leave it on
Turning vaporizers ON does not lower gas flow (Then verify vaporizer OFF)
N2O/O2 3:1 proportioner - linkage broken or gear stop misaligned
Obstruction in vaporizer or manifold

18. AGM Check: Low Pressure System (cont’d)
3.4 Verify Oxygen Supply Failure Alarm
Set all flowmeters to mid range
Drain O2 by pushing flush
Distinctive auditory pattern
Visual message on vent
Ensure that the low O2 pressure stops N2O but not air
Turn ON O2 cylinder to silence alarm
N20 and Air flow resume
Close all 3 gas flowmeters
Reconnect O2 pipeline
Verify Pipeline pressure
Alarm mechanism malfunction
No O2 supply alarm when O2 30 PSI
Shutoff valve for N2O fails to stop N2O when O2 20 PSI

19. AGM Check: Low Pressure System (cont’d)
3.5 Scavenging System
Ensure test lung is in place to collect waste anesthetic gas
Selector switch is in Bag/APL position
Open APL valve fully – flush occluded circuit with O2 – circuit pressure stays below 10 cm H2O
Empty reservoir bag and test lung in order to get rid of waste anesthetic gases into scavenger
The scavenger reservoir bag fills and the pressure relief valve releases
The scavenger reservoir bag should then deflate
Circuit breathing bag does not deflate
Hose from circuit to scavenger is blocked
Faulty positive pressure relief valve
No Vacuum, needle valve closed
Too much vacuum and faulty negative pressure relief valve

20. AGM Check: Breathing System
4.1 Check initial status of breathing system
4.2 Perform leak test - Bag / APL valve circuit
4.3 Check APL valve
4.4 Check the function of the unidirectional valves

21. AGM Check: Breathing System 2
4.1 Check initial status of breathing system
Circuit complete, undamaged, unobstructed
Verify CO2 absorbent is adequate (colour, quantity)
Attach gas sampling line to circuit
Set all flows to zero (or minimum)
manufacturing defects causing leaks or obstruction
foreign object obstructing e.g. sampling port cap inside elbow

22. AGM Check: Breathing System
Numerous leak sites possible
Auxiliary FGF outlet left open (alarm sounds)
CO2 canisters not locked into position
Faulty canister seals or granules are preventing a good seal
CO2 drain plug partially open
Unidirectional valve housing loose
O2 sensor not firmly seated in port or sensor housing is cracked
Flow sensor housing cracked
Pressure sensing tubing from gauge is not tightly connected (internal)
Leak in breathing bag, circuit hoses
Unused sampling ports not capped
Faulty selector switch - allows cross-over of gas into ventilator circuit
4.2 Perform leak test - Bag / APL valve circuit
Close APL valve (spare breathing bag is still attached to Y-piece)
Inflate bag with O2 flush to just < 40 cm H2O
Circuit pressure holds steady for > 10 secs
Sustained pressure alarm sounds
Ventilator bellows does not move

23. AGM Check: Breathing System 5
Improperly adjusted APL valve - set to release either too high or too low
No alarm - upper limit set too high
Cannot adjust pressure - valve sticking
(Sustained pressure limit is the high pressure limit or a max of 30 cm H2O)
4.3 Check APL valve
With APL valve still closed and circuit occluded, squeeze inflated bag until pressure reaches approx. 70 cm H2O
High pressure alarm sounds when limit exceeded (e.g. 40 cm H2O)
APL valve partially releases
Open APL valve slowly until pressure drops below 20 cm H2O, then stop
Pressure should stabilize and hold
Sustained pressure alarm stops

24. AGM Check: Breathing System 3
4.4 Check function of unidirectional valves
Attach a spare breathing bag to the inspiratory outlet of the absorber and close APL valve completely
Fill both test bag and reservoir bag with O2 flush until pressure gauge reads 35 cm H2O – pressure should hold
Open APL valve – pressure holds but only reservoir bag deflates
If needed, repeat test on expiratory inlet with inspiratory outlet occluded
Missing, incompetent valves or incorrectly seated
If pressure holds - both valves are competent
If reservoir bag deflates before opening APL valve - expiratory valve is leaking

25. AGM Check: Ventilation Systems
5.1 Test automatic ventilation system
5.2 Test manual ventilation system

26. AGM Check: Ventilation System
5.1 Test automatic ventilation system
Selector switch set to Ventilator - all flows set to minimum, breathing bag on Y-piece
Fill bellows with O2 flush between ventilator breaths - pressure does not exceed 15cm H2O - release flush
Set appropriate ventilator parameters for next patient - Inspiration - bellows delivers correct tidal volume - Expiration - bellows fills completely - Volume monitor is consistent with ventilator - Proper action of unidirectional valves
Defective ventilator relief valve - should release when > 2.5 cm H2O
Relief valve does not close to allow bellows to fill completely
Bellows housing not fastened tightly
Drive gas hose not firmly attached
Connection from absorber to bellows is leaking
Volume sensor faulty
Valves stick or do not seat properly

27. AGM Check: Ventilation System 1 (cont’d)
5.1 Test automatic ventilation system (cont’d)
Remove breathing bag from Y-piece while ventilator is still working
Low pressure alarm sounds (“Cannot drive bellows”) until breathing bag is replaced
Set selector switch back to Bag/APL (turns ventilator OFF) when bellows fully inflated
Ventilator bellows does not drift downward
Alarm faulty or ventilator senses pressure cm H2O with breathing bag off - obstruction somewhere?
Leak somewhere – see previous slide

28. AGM Check: Ventilation System 2
5.2 Test manual ventilation system
Switch in Bag/APL mode
Ventilate manually and assure inflation and deflation of artificial lungs and appropriate feel of system resistance and compliance
Remove second breathing bag from Y-piece
Faulty APL valve - incorrect pressure adjustment
Back to Menu

29. AGM Check: Final Status Checks
6.1 Gas machine and breathing system
6.2 Monitors

30. AGM Check: Final Status Checks 1
6.1 Gas machine and breathing system
Vaporizers OFF
Selector switch to Bag/APL and adjust APL valve to MIN
Set O2 flow to 3 L/min - other gases to zero
Attach face mask to Y-piece and through a surgical mask, breathe in and out through the circuit as final test
Set O2 flow to minimum

31. AGM Check: Final Status Checks 2
6.2 Monitors
Check that capnometer registers the CO2 from your breath - and apnea alarm sounds after appropriate interval; check alarm settings
Check oximeter on your own finger for function; check alarm settings
Make sure manual BP cuff is available
Patient suction adequate (“thumb test”)
Back to Menu