Example checking protocol for the
Aestiva 5 Anaesthetic machine
Key...

Machine is on standby
Machine is switched on - in Bag mode
Machine is switched on - in Vent mode
Initial setup...
Accessories...

Check draw for leads:
     - red invasive monitoring
     - blue temperature probe
     - orange entropy

Have available: Neostigmine/Glycopyrolate, Atropine, airways, syringes, needles, tapes.
Negative pressure leak test...
  1. Turn all flow controls 1½ turns anti-clockwise
  2. Fit bulb test device into Auxiliary Common Gas Outlet (ACGO)
  3. Switch on ACGO
  4. Switch vapouriser on @ 1%
  5. Deflate bulb (vacuum causes flow control floats to move)
  6. Bulb should not reinflate within 30 secs
  7. Repeat steps 4-6 for each vapouriser
  8. Turn off all gas flow controls (clockwise)
  9. Turn ACGO off
  10. Remove test device
  11. Depress drain button for 10 seconds
Vapouriser back-pressure test...
  • System switch and top monitor on
  • Set oxygen flow @ 6 L
  • Ensure oxygen flow is steady, and bobbins move freely
  • Adjust vapouriser to 1% - 1 click at a time

Ensure oxygen flow doesn't drop more than 1 L through range. If oxygen flow drops more than 1 L, either the vapouriser or the machine is faulty.
Cylinder checks...
  • Set flows @ 1 L
  • Turn on and check level of each cylinder (oxygen, N2O,Air)
  • Ensure bobbins move freely
  • Cylinders off - drain gases until gauges drop to nil
Other line checks...
  • Connect main pipelines
  • Check gas pressures (4 bar)
  • Check suction
  • Ensure active scavenging flow tube shows green
  • Ensure auxiliary oxygen flows
Oxygen calibration...
  • Unplug oxygen sensor
  • Do a 21% calibration test
  • If successful (30-40 secs), refit the sensor
  • If unsuccessful, do a 100% calibration test.

If still unsuccessful, replace sensor.
Hypoxic guard...
  • • Switch N2O and oxygen flows to minimum (clockwise)
  • • Increase N2O; check oxygen maintains 21% partial pressure
  • • Switch off oxygen, N2O should drop first
  • • Set oxygen, N2O, Air @ 1 L
  • • Disconnect main oxygen supply; wait for alarm
  • • Ensure N2O drops before oxygen - Air still flows
  • • Reconnect oxygen supply; check oxygen flow returns to 1 L
  • • Switch off N2O and Air
  • • Allow oxygen flow for 1 minute (to flush volatile agents)
PAW alarm checks...
  • Set oxygen flow @ 0.5 L*
  • Occlude patient end of circuit (reservoir bag)
  • Set APL (Adjustable Pressure Limiting) valve @ 30 cm/H2O**
  • Flush to 30 cm/H2O; force "Sustained PAW" alarm
  • Set APL valve @ 70 cm/H2O
  • Flush to 40 cm/H2O
  • Force "High PAW" alarm
  • Turn APL valve off

* Compensates for sampling line "leak".
** Normal lung pressure is 20-30 cm/H2O.
Ventilator settings...
  • Set: Vt = 400 ml
  • Breath rate = 12
  • I:E = 1:2
  • Set Volume mode
Ventilator operation...
  • Set the ventilation switch to Vent mode
  • Set oxygen flow to minimum
  • Flush with oxygen to fill bellows
  • Ensure VTE level reaches 90% VT (360 ml) within 6 cycles
  • Ensure 1-way inspiratory valve rises on inspiration
  • Ensure 1-way expiratory valve rises on expiration
  • Disconnect reservoir bag to force "cannot drive bellows" alarm
  • Reconnect reservoir bag
  • Flush bellows
  • With bellows at highest point, set switch to Bag mode*

* If bellows fall more than 100 ml/min, there is a leak in the ventilator circuit.
Standby mode...