Routine Anaesthetic Checks Flashcards
List the main topics for the ANAESTHETIC MACHINE CHECK
- POWER SUPPLY (With clock check and service history)
- MEDICAL GAS SUPPLY
- ANAESTHETIC MACHINE LEAKS
- VAPORIZER CHECK
- BREATHING SYSTEM INTEGRITY
- BREATHING SYSTEM LEAKS
- VENTILATOR CHECK
- MONITORS CHECK
- AIRWAY TROLLEY, BVM, RESUS Equipment checks
What are the 5 x POWER SUPPLY checks for the anaesthetic machine?
POWER, MAIN SWITCH, BATTERY, CLOCK, SERVICE Hx
- Connection to main power via its own designated emergency power source.
- Turn on master power switch
- Disconnect power mains to check machine battery.
- Is the system clock correct?
- Check service history/out of service labels?
MEDICAL GAS SUPPLY
GAS SUPPLY
1. Pipeline pressures - 4 x 100 kPa
- Check gas flow through variable orifice flowmeters (rotameters)
- Start with N2O to 3L/min (note spinning bobbins)
- Observe automatic O2 flow to 25% of N2O flow - Oxygen failure
- Disconnect O2 from wall supply
- Press O2 flush (flow of at least 30L/min) and observe bobbins:
- Note O2 supply alarm + warning on monitor and N2O dumping
- Emergency O2 cylinder check: open, seating, exclude leaks –> O2 failure alarm should disappear. Check cylinder gauge: < 50 x 100 kPa change cylinder. Max is 157 x 100 kPa. - Reconnect O2 hosing to the wall - perform tug test on all medical gases. Turn off O2 E-cylinder.
- O2 sensor calibration
- On ventilator control screen select calibrate O2 sensor - to room air 21% or 100% O2. Then either turn on Medical air or 100% O2. O2 sensor located at inspiratory limb of the breathing circuit. - Check that it is actually O2 in the mains supply –> dial in O2 concentration and check O2 sensor.
ANAESTHETIC MACHINE LEAKS
- Disconnect common gas outlet
- Occlude/disocclude (avoid HIGH pressures - can cause damage) the common gas outlet with preset flow and observe the rotameter bobbins and listen for leaks. If the bobbins bounce - unlikely significant leaks. If bobbins do not fall –> leak.
(Alternative: evacuated bulb test - stays evacuated for ≥30s) - Repeat the test with each vaporizer open - listen for leaks around each vaporizer
- Reconnect breathing circuit to common gas outlet
VAPORIZER CHECK
- Check the O-rings on the vaporizer manifold (back-bar)
- Ensure vaporizer sits flush on the back bar without tilt.
- Check safety interlock mechanism
- Check level of vaporizer fluid - not overfilled and that the filling port is tightly closed
BREATHING SYSTEM INTEGRITY
- CO2 absorber
- Colour: Minimal colour change
- Moisture: Appropriate quantity
- Seated correctly without leaks - Check pressure sensor and flow sensor connections to breathing circuit and to the back of the anaesthetic machine.
- Piping: Clean, no leaks, no water (Bain - use plunger of 2mL syringe to occlude inner tube at patient end and look for bobbin dip to prove no leak for connection at machine end of inner tube)
- Other apparatus checks:
- Scavenging: All connections securely connected.
- Filter
- Catheter mount
- Face masks
BREATHING CIRCUIT LEAKS AND VALVES
- Fully close APL valve and attach test lung.
- Build up pressure within the breathing circuit
- Turn off all FGF
- Squeeze bag
Observe for leaks - Partially open APL valve and ensure the APL allows gas escape, and check that the unidirectional valves are moving appropriately with inspiration and expiration.
VENTILATOR CHECK
- Select IPPV mode
- Ensure APL closed
- Dial in FGF rate
- Connect test lung
- Adjust FGF to very low levels –> if ventilator continues to work (Bag inflation/deflation continues) –> no leaks and system is working
- Assess bellows: Ensure bag seated correctly and ensure no leaks. If there is a leak the bellows will empty and wont refill –> triggering the apnoea alarm.
MONITOR CHECKS
Capnograph - check water trap (must be empty. Blow into the sample line. O2 analyzer (calibrated already) NIBP ECG Pulse Oximeter Alarm settings
When should an evacuated bulb test be used instead of FGO occlusion test?
In ventilators with built in automated check sequence - these are vulnerable to high pressure damage in the bouncing bobbins test.
What records should be kept for machine checks?
Morning and afternoon checks (at the start of every operating session) - name of person who completed the check. Some machines keep record of when checks were done.
What important check involving the BVM should be completed?
Check that the BVM can be connected to oxygen quickly as often the stepped nipple connector for the O2 tubing is incompatible
What is the mnemonic for all the anaesthetic checks
SAD MIMES
Suction
Airway trolley
Drugs: Emergency and planned
Machine Check (including breathing system)
Intravenous cannulae and fluids
Monitors
Emergency devices and drugs to deal with unexpected problems
Special: Regional block equipment, ultrasound machine
Suction
- Check both - anaesthetic room and theatre
- Check all connections
- Spare Yankauer and flexible tube catheters
- Pressure/flow test: Negative pressure of at least -80 kPa within 10 seconds (Flow 35 - 40 L/min)
Airway trolley
I.M.A.L.E.S
Introducers
Including Bougie
Magills’ forceps
Masks (2 sizes)
Airways (Oropharyngeal airways x 3 sizes) Alternative airway (LMA - check if inflatable x 2 sizes) Artery forceps (Secure breathing circuit to OR table)
Laryngoscope (Two blade sizes - adults: 3 and 4) - check illumination and bulb security
Laryngoscope (short handle for obstetrics)
Endotracheal tube (x 3 sizes) - check the cuff and load the stylet introducer - KY jelly - shape tube
Supplies
- Strapping (Securing ET tube)
- Syringe
- KY jelly
- HME filter
- Rigid Yankauer suction catheter
- BVM with RB and O2 supply tubing
- -> check reservoir bag, O2 tubing and valve check
