Anesthesia Machines (Exam III) Marcus's Cards

Question 1

What still works if master switch is off?

Answer 1

• Battery charger
• electrical outlets
• O2 flush valve

Question 2

What is the biggest power draw in an anesthesia machine?

Answer 2

Ventilator

Question 3

What are the electrical outlets on the anesthesia machine intended for?

Answer 3

Anesthesia monitors

Question 4

What all is part of the high pressure system?

Answer 4

• Cylinders
• Hanger yoke
• Check valve assembly
• Cylinder pressure indicators
• Pressure regulators

Question 5

What is the purpose of the high pressure system?

Answer 5

Reduce gas from cylinders to lower, more constant pressures suitable for the anesthesia machine

Question 6

What are the functions of the hanger yoke?

Answer 6

• Orient & support cylinder
• Provide gas-tight seal
• Ensure unidirectional flow

Question 7

What are the parts of the hanger yoke?

Answer 7

• Body
• Retaining screw: tightens cylinder
• Nipple: thru which gas enters machine
• Index pins
• Washer: forms seal between cylinder & yoke
• Check valve assembly: Ensures unidirectional flow

Question 8

What are the purposes of the hanger yoke check valve assembly?

Answer 8

• Ensures unidirectional flow
• Prevents gas from exiting machine when no cylinder is in the yoke

Question 9

Cylinder pressure gauges are required to be calibrated in what units?

Answer 9

kilopascals (kPa)

Question 10

Increasing pressure on a Bourdon tube increases or decreases the curve?

Answer 10

decreases or straightens

Question 11

What is the purpose of pressure regulators?
How many are there supposed to be?

Answer 11

• Reduce high variable pressure in cylinders to lower constant pressure for machines.
• One regulator for each gas supplied by a cylinder

Question 12

What is part of the Intermediate pressure sytem?

Answer 12

• Pneumatic part of master switch
• Pipeline inlet connections & indicators
• Piping
• Oxygen pressure failure devices
• Oxygen flush valve
• Flow control valves

Question 13

What is the pressure reading with the master switch turned off?

Answer 13

Zero

Question 14

What are the pipeline & cylinder pressures in the intermediate pressure system?

Answer 14

• Pipeline: 50-55 psi
• Cylinder: 45 psi

Question 15

What part of the intermediate pressure system relates to the DISS?

Answer 15

The pipeline inlet connections

Question 16

Pipeline inlet connections must have what?

Answer 16

Unidirectional check valves to prevent gas returning to pipeline

Question 17

Where are the pipeline pressure indicators located?
How many are there?

Answer 17

• Front of the anesthesia machine
• At least 1 for each gas

Question 18

What pressure does the intermediate pressure system piping have to withstand?
What about leaks?

Answer 18

• Must withstand 4x intended pressure. Around 200-220 psi
• Leaks must not exceed 25 mL/min

Question 19

What is happening if you hear an alarm about every 5 seconds?

Answer 19

The oxygen pressure is reduced to 30 psi

Question 20

What is the purpose of the O2 failure safety device?

Answer 20

• Decreases or discontinues N₂O when in use
• Maintains 19% O₂ concentration at common gas outlet
• Continues until O₂ flow ceases

Question 21

What is the flow when the O2 flush button is pressed?

Answer 21

35-75 L/min

Question 22

Where does the O₂ flush button send oxygen?

Answer 22

To the common gas outlet

Question 23

The oxygen flush must be what?

Answer 23

• Operable with 1 hand
• Single purpose
• self-closing
• designed to minimize accidental use
• have flow between 35-75 L/min

Question 24

What are the hazards of the oxygen flush?

Answer 24

• May cause barotrauma
• May cause awareness d/t backwash

Question 25

Flow adjustment controls must be?

Answer 25

• Only control one gas for each control knob/button
• Must be adjacent to its flowmeter
• O₂ flow knob must be larger & fluted compared to others

Question 26

What are the parts of the low pressure system?

Answer 26

• Flowmeters
• Hypoxia prevention devices
• Unidirectional valves
• Pressure relief devices
• common gas outlet

Question 27

The low pressure system starts where?

Answer 27

Downstream of flow control devices (Flowmeters)

Question 28

What design do flowmeters have?

Answer 28

Thorpe tube design

Question 29

Flowmeters empty into what?

Answer 29

Common manifold

Question 30

What is the correct flowmeter sequence?

Answer 30

• Left: N₂O or Air
• Middle: Air or N₂O
• Right: ALWAYS O₂

Question 31

What is the hypoxia prevention device?

Answer 31

• A minimum O₂ flow of 50-250 mL/min thru the machine
• Activated when master switch is turned on

Question 32

What is the minimum O₂ ratio?

Answer 32

• It uses a mechanical linkage between O₂ & N₂O to keep O₂ concentration at at least 25% when N₂O is turned up

Question 33

Where are the low pressure system unidirectional valves located?

Answer 33

• Between vaporizer & common gas outlet
• Upstream from O₂ flush valve

Question 34

Where are pressure relief devices located?How do they work?

Answer 34

• Near common gas outlet
• Open to atmosphere if preset pressure is exceeded

Question 35

What is a downside to pressure relief devices?

Answer 35

Limits the ability of the machine to provide adequate pressure for Jet ventilation

Question 36

What characteristic must the common gas outlet have?

Answer 36

Difficult to disconnect

Question 37

What should the common gas outlet not be used for?
Why?

Answer 37

• Supplemental O₂
• As it may deliver volatile anesthetics

Question 38

What is the alternative O₂ control used for?
Why should one be careful with it?

Answer 38

• Delivers O₂ in case of loss of electricity
• If turned on it will turn off power to rest of the anesthesia machine