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

AGM Check: Initial Steps 1. 1 Quick visual check 1. 2 Back-up ventilation equipment

AGM Check: Initial Steps 1 1. 1 Quick visual check for: ü ü Obvious damage / Missing components Bio. Med notice of Return-to-Service Electrical power cord plugged into receptacle with generator backup System master switch OFF Ø Red receptacle

AGM Check: Initial Steps 2 1. 2 Back-up ventilation equipment ü Self-inflating resus bag & O 2 source Back to Menu Ø Check for incorrect assembly / damaged parts

AGM Check: High Pressure System 2. 1 Check central pipeline supplies 2. 2 Check O 2 reserve cylinder supply

AGM Check: High Pressure System 1 2. 1 Check central pipeline supplies ü ü ü Hoses are connected correctly (colours, DISS) Pipeline gauges read 50 -55 psig Disconnect O 2 pipeline Ø Misconnections Ø Line pressure fluctuations Ø Failure of central O 2 supply

AGM Check: High Pressure System 2 2. 2 Check O 2 reserve cylinder supply ü ü Bleed O 2 cylinder pressure to zero with O 2 flush (O 2 pipeline disconnected) Open O 2 cylinder and verify at least half full (approx. 1000 psig) Ø Avoid reading “old” cylinder pressure Ø Check for wrong cylinder double gasket defeats pin index system or pins are broken Ø Dust protection cap still in place

AGM Check: High Pressure System 2 (cont’d) 2. 2 Check O 2 reserve cylinder supply (cont’d) ü Listen - no audible leak Ø Missing gasket; cylinder not seated in yoke properly Ø Cylinder valve stem loose Ø Unused yoke vacant with no yoke plug ü Open and close O 2 flowmeter - no flow seen Ø Machine master switch allows leak ü Close cylinder - pressure gauge drops less than 100 psig in five min Back to Menu Ø Cylinder control valve leaks Ø Leaking pipeline check valve

AGM Check: Low-Pressure System 3. 1 Check vaporizer installation 3. 2 Perform low-pressure leak test 3. 3 Turn ON gas machine master switch 3. 4 Test flowmeters

AGM Check: Low Pressure System 1 3. 1 Check vaporizer installation ü ü ü Tops of vaporizers are parallel to manifold - cannot be lifted off manifold Vaporizers are full and fill ports closed Verify all vaporizers OFF Ø Vaporizer not locked on to manifold properly Ø Overfilling of vaporizer

AGM Check: Low Pressure System 2 3. 2 Perform low-pressure leak test ü ü 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 Ø Defective suction bulb Ø Leak somewhere between flow control valves and common gas outlet • Cracked, loose, misaligned flow tubes • Loose connections – internal piping, components

AGM Check: Low Pressure System 2 (cont’d) 3. 2 Perform low-pressure leak test ü Repeat leak test for each vaporizer, one at a time setting dial to 1% conc. Ø Partially open filler/drain port Ø Missing vaporizer port O-ring on manifold ü Verify with each vaporizer that the other vaporizer(s) cannot be turned ON Verify all vaporizers OFF, aux. gas outlet closed, and flush system with O 2 Ø Faulty interlock mechanism - can turn on two vaporizers simultaneously Ø Vaporizer will not turn ON interlock obstructed by ECG lead, etc ü

AGM Check: Low Pressure System 3 3. 3 Verify Electrical Power and Oxygen Supply Failure Alarm ü ü Unplug machine power from electrical receptacle Turn ON master switch Verify “Battery Power OK” message, plug in power cord and message disappears Ø Battery discharged because machine previously left ON and unplugged from AC outlet ü Turn ON vital signs monitor Ø Allows gas analyzer to “warm up” ü

AGM Check: Low Pressure System 3 (cont’d) 3. 3 Verify Electrical Power and Oxygen Supply Failure Alarm (cont’d) ü ü ü Verify O 2 supply failure alarm ü Drain O 2 – press O 2 Flush ü Distinctive auditory pattern ü Visual message on Vent Turn ON O 2 cylinder to silence alarm Remove O 2 sensor from circuit Ø Alarm mechanism malfunction Ø Exposes O 2 sensor to room Air for later calibration

AGM Check: Low Pressure System 4 3. 4 Test flowmeters ü ü Minimum flows are 25 ml/min for O 2 and zero ml/min for other gases Flowtubes are undamaged; floats move smoothly throughout their full range Ø No flow - broken tip of needle valve Ø Floats sticking - dirt, grease, static Ø Float stuck at top of flow tube Ø Stop broken off from top of flow tube and resting on float

AGM Check: Low Pressure System 4 (cont’d) 3. 4 Test flowmeters (cont’d) ü O 2 and N 2 O flow controls cannot supply hypoxic flowrates Ø N 2 O/O 2 3: 1 proportioner linkage broken or gear stop misaligned ü Turning vaporizer ON does not lower gas flow (Then verify vaporizer OFF) Ø Obstruction in vaporizer or manifold

AGM Check: Low Pressure System 4 (cont’d) 3. 4 Test flowmeters (cont’d) ü ü Low O 2 pressure stops N 2 O gas flow but NOT Air • Set all 3 floats to mid-range - close O 2 cylinder - push O 2 flush • O 2 supply failure alarm sounds and N 2 O float drops while Air continues Close all 3 gas flow controls and reconnect O 2 pipeline - verify pipeline pressure Back to Menu Ø No low O 2 supply alarm when O 2 supply pressure@ 30 psig Ø Shutoff valve for N 2 O fails to close when O 2 @ 20 psig

AGM Check: Breathing System 4. 1 Calibrate O 2 monitor 4. 2 Check initial status of breathing system 4. 3 Check function of unidirectional valves 4. 4 Perform leak test - Bag / APL valve circuit 4. 5 Check APL valve and scavenging system

AGM Check: Breathing System 1 4. 1 Calibrate O 2 monitor ü ü ü Ensure monitor reads 21% with sensor in room air Verify low O 2 alarm enabled by breathing on to sensor through your surgical mask Reinstall sensor in circuit - flush breathing system with O 2 - monitor should read > 95% Ø cannot calibrate - faulty fuel cell Ø crossover between O 2 supply and other gas - hospital piping, hoses or in gas machine Ø wrong gas in central supply / cylinder

AGM Check: Breathing System 2 4. 2 Check initial status of breathing system ü ü Set selector switch to “Bag/APL” Circuit complete, undamaged, unobstructed ü Verify CO 2 absorbent is adequate (colour, quantity) ü Attach gas sampling line to circuit ü Set all flows to zero (or minimum) Ø manufacturing defects causing leaks or obstruction Ø foreign object obstructing e. g. sampling port cap inside elbow

AGM Check: Breathing System 3 4. 3 Check function of unidirectional valves ü ü 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 O 2 flush until pressure gauge reads 35 cm H 2 O – pressure should hold Open APL valve – pressure holds but only reservoir bag deflates If needed, repeat test on expiratory inlet with inspiratory outlet occluded Ø Missing, incompetent valves or incorrectly seated Ø If pressure holds - both valves are competent Ø If reservoir bag deflates before opening APL valve - expiratory valve is leaking

AGM Check: Breathing System 4 4. 4 Perform leak test - Bag / APL valve circuit ü ü ü Set selector switch to Bag/APL close APL valve and attach spare breathing bag to Y-piece Inflate bag with O 2 flush to just < 40 cm H 2 O Circuit pressure holds steady for > 10 secs • ü Sustained pressure alarm sounds Ventilator bellows does not move Numerous leak sites possible ØAuxiliary FGF outlet left open (alarm sounds) ØCO 2 canisters not locked into position ØFaulty canister seals or granules are preventing a good seal ØCO 2 drain plug partially open ØUnidirectional valve housing loose ØO 2 sensor not firmly seated in port or sensor housing is cracked ØFlow sensor housing cracked ØPressure sensing tubing from gauge is not tightly connected (internal) ØLeak in breathing bag, circuit hoses ØUnused sampling ports not capped ØFaulty selector switch - allows crossover of gas into ventilator circuit

AGM Check: Breathing System 5 4. 5 Check APL valve and scavenging system ü With APL valve still closed and Ø Improperly adjusted APL valve circuit occluded, squeeze inflated - set to release either too high bag until pressure reaches approx. or too low 70 cm H 2 O Ø No alarm - upper limit set too • High pressure alarm sounds when high • ü limit exceeded (e. g. 40 cm H 2 O) APL valve partially releases and reservoir bag on scavenger fills Ø Cannot adjust pressure - valve sticking Ø (Sustained pressure limit is the high pressure limit or a max of Pressure should stabilize and hold 30 cm H 2 O) Sustained pressure alarm stops Open APL valve slowly until pressure drops below 20 cm H 2 O, then stop • •

AGM Check: Breathing System 5 (cont’d) 4. 5 Check APL valve and scavenging system (cont’d) ü Open APL valve fully, flush occluded circuit with O 2 • • ü Circuit pressure stays < 10 cm H 2 O Scavenging reservoir bag fills and then positive pressure relief valve releases APL valve fully open, flows set at minimum and circuit still occluded • • Back to Menu Circuit breathing bag does not deflate Scavenging reservoir bag does deflate Ø opening pressure of APL too high Ø hose from circuit to scavenger blocked Ø faulty positive pressure relief valve on scavenger Ø opening pressure of APL too low Ø too much vacuum and faulty negative pressure relief valve Ø no vacuum; needle valve closed

AGM Check: Ventilation Systems 5. 1 Test automatic ventilation system 5. 2 Test manual ventilation system

AGM Check: Ventilation System 1 5. 1 Test automatic ventilation system Ø Defective ventilator relief valve should release when > 2. 5 cm H 2 O ü Selector switch set to Ventilator - all flows set to minimum, breathing bag on Y-piece ü Fill bellows with O 2 flush between Ø Relief valve does not close to ventilator breaths allow bellows to fill completely - pressure does not exceed 15 cm H 2 O Ø Bellows housing not fastened - release flush tightly Set appropriate ventilator Ø Drive gas hose not firmly attached parameters for next patient Ø Connection from absorber to - Inspiration - bellows delivers correct bellows is leaking ü tidal volume - Expiration - bellows fills completely - Volume monitor is consistent with ventilator - Proper action of unidirectional valves Ø Volume sensor faulty Ø Valves stick or do not seat properly

AGM Check: Ventilation System 1 (cont’d) 5. 1 Test automatic ventilation system (cont’d) ü ü Remove breathing bag from Ypiece 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 Ø Alarm faulty OR ventilator senses pressure 4 - 9 cm H 2 O with breathing bag off obstruction somewhere? Ø Leak somewhere – see previous slide

AGM Check: Ventilation System 2 5. 2 Test manual ventilation system ü ü ü Switch in Bag/APL mode Ventilate manually and assure inflation and deflation of artificial Ø Faulty APL valve - incorrect lungs and appropriate feel of pressure adjustment system resistance and compliance Remove second breathing bag from Y-piece Back to Menu

AGM Check: Final Status Checks 6. 1 Gas machine and breathing system 6. 2 Monitors

AGM Check: Final Status Checks 1 6. 1 Gas machine and breathing system ü ü ü Vaporizers OFF Selector switch to Bag/APL and adjust APL valve to MIN Set O 2 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 O 2 flow to minimum

AGM Check: Final Status Checks 2 6. 2 Monitors ü ü Check that capnometer registers the CO 2 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