Anesthesia Machine Pre-Use Checklist

Note: Because modern anesthesia workstations differ widely, no single procedural checklist applies to all machines. Each department should develop a machine-specific version based on these principles and the manufacturer's manual. Items marked * must be completed before every case, not just daily.

FREQUENCY KEY

• D = Daily (or when machine is moved / vaporizer changed)
• E = Before every case

SECTION 1 - Emergency Backup (D)

• Confirm a self-inflating manual resuscitation bag (e.g., Ambu bag) is present and functional at every anesthetizing location
• A non-self-inflating Mapleson circuit is NOT adequate as backup
• Confirm a portable oxygen cylinder is present, separate from the wall supply, with an attached flowmeter and cylinder wrench
• Open the cylinder to confirm it is adequately filled; then close the valve

SECTION 2 - Electrical Power (D)

• Confirm the machine is plugged into AC mains power
• Turn on the anesthesia delivery system and all required electrical equipment
• Some machines perform an automatic battery test during startup; verify battery backup function if not automated
• Modern workstations run automatic self-check routines - confirm all automated checks pass

SECTION 3 - Suction (E)

• Confirm functioning suction with tubing of adequate length
• Confirm a Yankauer suction tip is present and functional
• Test suction strength before every case

SECTION 4 - Monitors & Alarms (E)

• Confirm availability and function of all ASA standard monitors:
  • Pulse oximeter (with probe)
  • Capnograph (with sampling line connected)
  • Oxygen analyzer
  • Respiratory volume monitor (spirometer)
  • Breathing-system pressure monitor with high and low alarms
  • Blood pressure cuff (appropriate size)
  • ECG
• Enable all alarms, set thresholds to departmental defaults, and confirm audible alarm volume is sufficient

SECTION 5 - Gas Supply: High-Pressure System (D)

• Open the O2 cylinder mounted on the back of the machine
• Verify adequate pressure (≥ half full, ~1000 psig for a full E-cylinder)
• Close the cylinder valve after checking

• Confirm all pipeline hoses are connected to the correct wall outlets (check pin-index or DISS fittings)
• Verify pipeline gauge pressures are ≥ 50 psig (typically ~50-55 psig)
• If N2O or air is used, confirm those pipeline supplies are also connected and at adequate pressure

SECTION 6 - Low-Pressure System (D + E)

• Confirm vaporizer(s) are correctly seated and locked in place on the manifold
• Check agent fill level; refill if needed
• Tightly close all filler ports
• Confirm only one vaporizer is enabled at a time

• Close all flow control valves and turn all vaporizers off
• Attach the negative-pressure suction bulb to the common gas outlet
• Squeeze the bulb until fully collapsed; it should remain collapsed for ≥ 10 seconds (no leak)
• Repeat with each vaporizer turned on individually
• Remove the bulb and reconnect the fresh gas hose

On machines WITHOUT an outlet check valve, a positive-pressure breathing circuit test will also detect low-pressure leaks.

SECTION 7 - Flow Meters & Hypoxic Guard (D)

• Turn on the machine master switch
• Attempt to dial a hypoxic O2/N2O mixture (< 21% O2)
• Verify the anti-hypoxic device prevents this (flow changes or alarm activates)
• Confirm all flowmeter bobbins/balls move freely and read zero at minimum flow

SECTION 8 - Scavenging System (D)

• Verify proper connections between the scavenging system and:
  • The APL (pop-off) valve
  • The ventilator relief valve
• Adjust waste-gas vacuum to the recommended setting
• Fully open the APL valve and occlude the Y-piece
• With minimum O2 flow: allow scavenger reservoir bag to collapse - absorber pressure gauge should read ~0 cm H2O
• With O2 flush active: allow scavenger bag to fully distend - absorber pressure gauge should read < 10 cm H2O

SECTION 9 - Breathing System (E)

• Expose the O2 sensor to room air and confirm reading = 21%
• Verify the low-O2 alarm is enabled and functioning
• Reinstall the sensor in the circuit; flush with O2 and confirm reading > 90%
• Calibrate or verify calibration of the capnometer and anesthetic agent analyzers

• Set the selector switch to Bag mode
• Confirm the breathing circuit is complete, undamaged, unobstructed, and properly assembled
• Verify CO2 absorbent (soda lime/Amsorb) is not exhausted (not discolored, not hardened)
• Install any accessory equipment to be used (humidifier, PEEP valve, HME filter)

• Set all gas flows to zero (or minimum)
• Close the APL valve and occlude the Y-piece
• Pressurize the circuit to ~30 cm H2O using the O2 flush
• Confirm pressure remains stable for ≥ 10 seconds (no leak)
• Open the APL valve and verify pressure drops promptly to zero

• Test APL valve: after pressurizing the circuit, open the APL valve and confirm rapid pressure release
• Confirm unidirectional (inspiratory and expiratory) valves are seated and moving correctly

SECTION 10 - Ventilator (E)

• Place a test lung or second breathing bag on the Y-piece
• Set appropriate ventilator parameters for the next patient
• Switch to ventilator mode; turn on the ventilator
• Fill the bellows and breathing bag with O2 flush; set O2 flow to minimum
• Confirm the bellows fills and empties correctly during the ventilator cycle
• Confirm the breathing bag on the Y-piece moves appropriately (ventilator tidal volumes visible)
• Switch back to bag (manual) mode and confirm bellows ceases cycling
• Test the O2 flush button - confirm no major change in tidal volume (no "flush dumping")
• Perform the flow test: manually ventilate the test lung in a to-and-fro motion; confirm inspiratory valve opens during inspiration and expiratory valve opens during exhalation - feel for obstruction in either limb

SECTION 11 - Final Checks (E)

• Functioning laryngoscope with backup blade
• Appropriate endotracheal tubes (with stylet) and oropharyngeal/nasopharyngeal airways
• Magill forceps
• Difficult airway supplies as appropriate (videolaryngoscope, LMAs, bougie)

• Induction agents, opioids, muscle relaxants drawn up and labeled
• Resuscitation drugs available (ephedrine, epinephrine, atropine, succinylcholine)
• IV fluids and giving sets ready

• Defibrillator functional and immediately accessible
• Difficult airway kit available
• Malignant hyperthermia (MH) kit immediately accessible (if applicable)
• Emergency drug kit confirmed

SECTION 12 - Documentation & Time-Out (E)

• Record completion of the checkout in the anesthetic record
• Departments should maintain a log for quality assurance purposes

• Confirm ventilator settings are appropriate for the patient
• Review the surgical safety checklist (Sign-In)
• Confirm patient identity, procedure, allergies, NPO status, and site marking
• Confirm team briefing is complete before induction

Quick Summary: The 15 Items of the 2008 ASA PAC

• Morgan & Mikhail's Clinical Anesthesiology, 7e, Table 4-3 (FDA Anesthesia Apparatus Checkout Recommendations)
• Miller's Anesthesia, 10e, Chapter 20 - Items 1-15 of the 2008 ASA Pre-Anesthesia Checkout Recommendations
• Canadian Anesthesiologists' Society Pre-Anesthetic Checklist (2022), based on 2008 ASA guidelines