IHSMachineFlashCards.txt

• American Society for Testing & Materials
• ATSM

ATSM F1850

Yes

• 1) 30 minute battery backup
• 2) alarms: high, medium, and low priority
• 3) Monitors
• 4) Hypoxic guard system
• 5) Gas monitoring
• 6) Pulse oximetry, EKG, and BP monitoring
• 7) Breathing circuit pressure limited to 125cmH2O (12.5kPa)
• 8) Detachable resistant or non-detachable electric supply cord
• 9) At least 1 backup oxygen cylinder
• 10) Flowmeters
• 11) Auxillary oxygen flowmeter recommended
• 12) Oxygen flush capable of 35-75lpm that bypasses vaporizers
• 13) Vaporizer features

Rate of power consumption; it assumes you're hand ventilating

Cannot be silenced >120 seconds

Must be automatically enabled and functioning prior to use by turning the machine on or by following the pre-use checklist

• 1) breathing circuit pressure
• 2) oxygen concentration
• 3) exhaled volume and/or ETCO2

• 1) user adjustable limits are exceeded (high peak airway pressure)
• 2) continuing high airway pressure (APL valve closed)
• 3) Negative pressure (attempted inhalation against obstruction)

• 1) low pressure
• 2) exhaled volume
• 3) CO2

• 1) exhaled volume
• 2) inspired oxygen with high priority alarm within 30 seconds if oxygen < 18% (or user set limit)
• 3) oxygen supply failure alarm

<21% oxygen mixture when nitrous oxide is in use

• 1) a PISS hanger yoke
• 2) clamping device that resists leaks
• 3) a filter
• 4) check valve to prevent trans filling tank-to-tank
• 5) cylinder pressure gauge
• 6) cylinder pressure regulator
• 7) the machine must use pipeline gas as long as pipeline pressure >50psi (345kPa)

• 1) single control for each gas
• 2) each flow control is next to flow indicator
• 3) uniquely shaped oxygen flow control knob
• 4) valve stops to prevent excessive rotation and flowmeter damage
• 5) oxygen flow indicator is to the right side of the flowmeter bank
• 6) oxygen enters the common gas manifold downstream of other gases

• 1) concentration-calibrated
• 2) interlock system
• 3) liquid level indicator to prevent overfilling
• 4) "should" used keyed-filler devices
• 5) no discharge of liquid anesthetic occurs from vaporizer even at maximum fresh gas flow

Electrical and pneumatic system

AC power into the machine

Yes but it is on battery power and the electrical outlets are off.

• 4 Cs
• Communicate
• Check power cord
• Check outlet
• Conserve power

To charge the battery

• Monitors
• Do not use for any device that produces heat: bair hugger, fluid warmer, bovie
• Not powered if machine is unplugged or mains power switch is off

Reduce load, reset breaker

High, intermediate, and low pressure

• 1) gases from cylinder at variable pressure from hanger yoke
• 2) PISS, nipple, and O-ring
• 3) debris filter
• 4) check valve
• 5) cylinder pressure gauge
• 6) primary pressure regulator

Tank pressure (800-2200psi down to 50psi for Oxygen; 745 to 50psi for nitrous)

Backup only, not a primary source of gas

Petroleum based products - may cause adiabatic explosion if there is a rapid increase in heat when tank turned on quickly in the presence of a petroleum fuel

Primary pressure regulator

• Placed in hanger yoke when cylinder is empty and another is not available
• Backup to prevent gas escape in the event of check valve failure

• 1) gases from either pipeline connection (50-55psi) or pressure regulated gases from the high pressure system (45-50psi)
• 2) check valve to prevent backflow into pipeline
• 3) filter
• 4) gauges for pipeline pressure
• 5) pressure relief valve to avoid over-pressurization
• 6) flush valve
• 7) master switch - pneumatic component
• 8) oxygen failure safety device
• 9) secondary pressure regulator
• 10) flow control valves

Flowmeter

DISS

Directly from the first-stage pressure regulator to the common gas outlet at 35-75lpm @ 45-55psi

Vents all pressure in the intermediate system and beyond to zero

Prevent delivery of gas mixture that does not contain oxygen

Fail safe

• Either shuts off or proportionally decreases and eventually shuts off non-oxygen gas flow
• Prevent nitrous only gas flow in the event of loss of oxygen pressure

• Sounds in less than 5 seconds when oxygen pressure less than 30psi
• Prevents inhalation of gas containing <21%

• They do not detect the composition of the gas, only the pressure
• Do not prevent gas other than oxygen from being supplied through oxygen line
• Depend on pressure, not gas composition

• Prevents using a combination of air and nitrous
• Must use oxygen and air or oxygen and nitrous

• Oxygen 14 psi
• Nitrous 26 psi

• Create fail safe with pressure difference to prevent running nitrous without oxygen
• Helps reduce pressure fluctuations at flowmeters thereby reducing flow fluctuations

So you can find it in the dark

Mechanical backup in the event of power failure

• 1) flowmeters
• 2) vaporizers
• 3) auxillary or courtesy oxygen flowmeter (side-port)
• 4) common gas outlet
• 5) unidirectional valves
• 6) patient

Slightly above atmospheric pressure

• 1) total flow
• 2) back-pressure devices
• 3) back-pressure from breathing system

Prevent pt from breathing into the machine

• 20 degrees C
• 760mmHg

Will have greater than dialed flow due to reduced atmospheric resistance

• 1) pressure drop across constriction
• 2) size of annular opening
• 3) physical properties of the gas

Middle

Series

Safer in the event of bank or flowmeter failure to prevent hypoxic gas delivery

No they're specific to each gas

• Older machines would have oxygen flow of 50-250ml/min when flowmeter in full off position with pneumatic system on
• Reduces nitrous flow to maintain oxygen >25%
• Aka proportioning system

Mechanical proportioning system to prevent <25% oxygen delivery with nitrous

• Between vaporizers and common gas outlet
• Prevent pt from exhaling into the flowmeters/vaporizers

During spontaneous or manual ventilation

• Limits the amount of pressure buildup possible during manual ventilation
• Should be kept open unless giving positive pressure ventilation