Exam 3- Anesthesia Machines I (7-8-25)- SS cards

Question 1

How does excess gas leave the circuit? (2)

Answer 1

1. APL
2. Ventilator billows & pressure relief valve

Question 2

CGO =

Answer 2

Common gas outlet

Question 3

The ___________ set standards for the anesthesia machince since _____. The last time the standards were updated was in ________. What are the main differences from 2005 to now in regards to the anesthesia machine?

Answer 3

American Society for testing and materials

1979

2005

Just more technological advances but the basics are still the same (just fancier)

Question 4

The anesthesia machine is also called the anesthesia _______. Why? What does it include? (4)

Answer 4

“Anesthesia workstation”

The word “Workstation” is more inclusive of all the things the anesthesia machine has (vs “machine”)

1. Gas device
2. Ventilator
3. Monitoring devices
4. Protective devices

Question 5

What should the anesthesia workstation do? (5)

Answer 5

1. Provide accurate/safe gas delivery
2. Provider means for ventilating pt (independently of bagging/masking)
3. Provide electrical outlets on the back
4. Provide housing for monitoring devices
5. Provide storage/shelving (on top of machine)

Question 6

What should you plug into the anesthesia machine outlets? Why?

Answer 6

STUFF THAT ANESTHESIA (YOU) NEED FOR SX!!!!!!

NOT STUFF FOR THE SURGEON OR OTHERS

DONT LET NOBODY PLUG THEY STUFF INTO YOUR ISH!! MAKE THEM FIND THEY OWN OUTLET!!!!

Can overload machine –> circuit breakers activate –> shut down machine entirely

Question 7

_________ (2) functions are enabled when the master switch is ON. What does this activate? What can be bypassed?

Answer 7

1. pneumatic functions
2. Electrical functions

Alarms & safety features

Power-up protocols (SAMMTIDE) can be bypassed BUT a record is kept when machine check was last done.

Question 8

Pneumatic & electrical functions are ________ when the master switch is OFF. What are the exceptions? (4)

Answer 8

Disabled

Pneumatic:
1. O2 flush valve
2. Axillary O2 flow meter (able to bag pt or hook up NC, etc)

Electrical:
1. Battery charger
2. Electrical outlet

Question 9

There will be an _________ (2) indicator of power failure with the anesthesia machine. How does keeping the anesthesia machine plugged in affect this?

Answer 9

1. Visual
2. Audible

Keeps backup battery at its highest level

Question 10

The duration of the backup battery depends on _________. Example.

Answer 10

Power usage

Manual/hand ventilation uses no power vs ventilator mode that uses power.

Question 11

The anesthesia machine needs to be plugged into the _______ colored outlets. Why?

Answer 11

Red

They are backed up to generators in case the hospital loses power

Question 12

Equation: Ohm’s law

Answer 12

Flow = (Pressure / Resistance)

Question 13

What are the basic functions of the Pneumatic system? (3)

Answer 13

1. Receive gases from a supply
2. Create a gas mixture of unknown composition (whatever we turned on)
3. Deliver to CGO atmospheric pressure

Question 14

What are the three parts of the pneumatic system?

Answer 14

1. High-pressure (left)
2. Intermediate pressure (middle)
3. Low pressure (right)

Question 15

Compressed gas cylinders are included in the __________ of the pneumatic system.

Answer 15

High-pressure system

Question 16

What is all included in the High pressure system of the pneumatic system? (6)

Answer 16

1. Cylinders
2. Check valves
3. Filters
4. Pressure gauges
5. primary pressure regulator
6. Compressed gas lines

Question 17

In the High Pressure system in the pneumatics system, you receive gas at _________ (2) pressures at approximately ________.

Answer 17

High
Variable

2200 psi

(we dont want to inhale gaeses at this high of a pressure)

Question 18

The __________ reduces the pressure of gases received from cylinders in the High Pressure system in the pneumatics system to a more ______ pressure of _______

Answer 18

1st stage pressure regulators

Constant (& lower)

45 psi

Question 19

A _______ allows cylinders to get attached to the anesthesia machine. What are the functions of them? (3)

Answer 19

Hanger Yoke

functions:
1. Orient/supports cylinder
2. Provides a gas tight seal
3. Ensures unidirectional flow (cylinder –> machine)

Question 20

The anesthesia machine is required to have at LEAST 1 yoke ______ & 1 for ______. Where are they?

Answer 20

Oxygen

Nitrous

Attached to the anesthesia machine

(SN: you can have more but these are required)

Question 21

What are the parts of the Hanger Yoke? Briefly describe them (6)

Answer 21

1. Body: frame
2. Retaining screw: tighten cylinder (clamp)
3. Nipple: gas enters machine thru here
4. Index pins: PISS - prevents incorrect attachments
5. Washer: form seal between cylinder & yoke
6. Check valve assembly: ensures unidirectional flow

Question 22

What exactly is the purpose of the Check Valve Assembly?

Answer 22

Ensure Unidirectional Flow

-Prevents gas from exiting machine when there is no cylinder in yoke –> prevents gas from going into atmosphere

-prevent gas from being transferred from a cylinder with higher pressure to another with lower pressure –> prevents gas from going between cylinders
(when both in yoke & ON)

Question 23

A ________ must be present for each gas supplied by cylinders. They work on a ________ philosophy. Describe this

Answer 23

Cylinder pressure indicator

Bourdon tubes:
-curved hollow tubes
-analogue pressure devices

Pressure changes increase/decrease curve –> motion transmitted to gauge –> causes needle to move

Question 24

Cylinder pressure indicator gauges are required to be calibrated in _____________. What is the secondary?

Answer 24

Kilopascals (kPa)

psi

Question 25

Where does Intermediate pressure system in the pneumatic system received gas from? (2) What are the pressures of these gases?

Answer 25

**1st stage pressure regulator** from the high pressure system = 45 psi Pipeline/wall inlet = 50 - 55 psi

Question 26

If master switch is OFF, intermediate pressure system pressure is ____

Answer 26

0

Question 27

What does the intermediate pressure system of the pneumatic system include?

Answer 27

1. Pneumatic part of master switch 2. Pipeline inlet connections & indicators (DISS) 3. Piping 4. Oxygen pressure failure devices (safety devices) 5. Oxygen flush valve 6. Flow control valves (not the flow meter, just the control knob) (SN: Pipeline inlet, pressure relief valves, check valves, filter, secondary pressure regulators, compressed gas connections)

Question 28

The entry point for gases from pipelines is the ____________. Which are required? (2) which is not required?

Answer 28

Pipeline inlet connections 1. Oxygen 2. Nitrous NOT REQUIRED: Air (but most have it)

Question 29

The pipeline inlet connections are fitted with ______ & must contain __________ to prevent gas returning to pipeline/atmosphere

Answer 29

DISS Unidirectional check valves

Question 30

________________ indicators are required for each gas monitored and are found all the _____ of the anesthesia machine. They have to be located on the ________ side.

Answer 30

Pipeline pressure indicators Front -digital/new machines maybe on the LED screen Pipeline

Question 31

An image on a tank by the gauge represents what? Without it represents what?

Answer 31

Cylinder/tank pressure Pipeline/Wall inlet pressure

Question 32

The _____ connects the components inside the machine. What are the standards for this? (2)

Answer 32

Piping 1. Required to withstand 4x intended pressure 2. Leaks must not exceed 25 ml/min inside machine

Question 33

The other name for the oxygen failure safety device is ________. Describe the safety device

Answer 33

Oxygen failure protection device O2 pressure below 30 psi: -diaphragm decreases -nitrous flow decreases O2 pressure below 20 psi: -Nitrous flow closed completely off -only O2 is delivered to CGO **O2 failure alarm will sound within 5 secs**

Question 34

O2 flush receives oxygen from ________ (2) and since O2 to ______

Answer 34

1. Pipeline inlets 2. Cylinder pressure regulators CGO

Question 35

What are the standards that an O2 flush are required to have?

Answer 35

1. Operable w/ 1 hand 2. Single purpose 3. Self closing 4. Designed to minimize accidental use (recessed w/ ridge) 5. **Flow between 35 - 75 L/min** (barotrauma)

Question 36

What are the harzards of the O2 flush? (2)

Answer 36

May stick on: 1. Barotrauma 2. Awareness (dt dilution of gas)

Question 37

________ regulate flow of oxygen, air, other gases. They can be _________ or _______. What are the standards required for these? (3)

Answer 37

Flow adjustment controls Mechanical Electronic Standards: 1. Must have only 1 control for each gas 2. Must be adjacent to its flowmeter 3. **Oxygen flow knob must be fluted and larger than others**

Question 38

What does the Low Pressure system of the pneumatic system control? Describe the pressure here? What does it depend on?

Answer 38

Downstream of flow control devices Slightly above atmospheric pressure & variable **Depends on flow from flowmeter & back pressure from breathing circuit** ## Footnote Low= geta **CUP** of **H**ot **F**udge

Question 39

What does the low pressure system of the pneumatic system include? (5)

Answer 39

1. Flowmeter 2. Hypoxia prevention devices 3. Unidirectional valves 4. Pressure relief devices 5. Common gas outlet --> to pte

Question 40

What are flowmeters built to do? What are the standards required of them? (3)

Answer 40

Indicate rate that gas is passing through 1. Must be marked with appropriate color/chemical symbol (Ex. O2 flowmeter = green) 2. 2nd stage regulator maintains 14-30 psi 3. Empty gases into common manifold

Question 41

Flowmeters are designed w/ _________. This is a _____ glass tube has the ______ diameter at the bottom. Describe how it works

Answer 41

Thorpe Tube Vertical Smallest There is a **flow scale** that has a **free floating indicator** in the **center**. Being in the center helps **maintain laminar flow**. As **flow increases** through the tube --> **indicator rises**. There's a stop at the top of the tube to prevent the indicator from going higher

Question 42

What are the different type of Flowmeter indicators? (4) Generally describe them

Answer 42

1. Ball type -read from middle 2. Non-Rotating type 3. Skirted 4. Non-Skirted The rest are read from the top Skirted & non-skirted spin continuously so you know they aren't stuck

Question 43

Normal flowmeter sequence has gas flowing from _______ & _______. What is the standard that is required w/ this? Why?

Answer 43

Bottom – top (in flowmeter) Left – right (across machine) Oxygen flow meter is required to be placed on the R side (nearest the CGO) If there's a leak in a flowmeter upstream, gases like nitrous or air would leak 1st. Placing O₂ last ensures it still enters the CGO and minimizes the risk of delivering a hypoxic mixture to pt.

Question 44

What is the flowmeter sequence of the Drager?

Answer 44

Nitrous --> air --> O2

Question 45

What is the flowmeter sequence of the Ohmeda?

Answer 45

Air --> nitrous --> O2

Question 46

What are the hypoxia prevention devices? (2) Describe them?

Answer 46

1. Mandatory minimum oxygen flow -activated when master switch ON -**delivers minimum of 50-250 ml/min flow** 2. Minimum oxygen ratio -engages when oxygen concentration is at 25% or below -**mechanical linkage w/ nitrous automatically decreases it concentration** to prevent hypoxic mixtures

Question 47

T/F: the oxygen/nitrous linkage is only activated when nitrous is turned on

Answer 47

T Linkage is not active when only using oxygen. It's active when using nitrous to help prevent hypoxic mixtures if the O2/nitrous ratio is off

Question 48

The unidirectional valves in the low pressure system of the pneumatic system are located between ______ & ________. They are upstream from __________. What do they do?

Answer 48

Vaporizer CGO Oxygen flush valve Lessens back pressure from flush or breathing circuit

Question 49

The pressure relief devices in the low pressure system of the pneumatic system are located near the ________. What do they do? What limitations does this have?

Answer 49

CGO Open to atmosphere & vents if preset pressure is exceeded Limitations: Prevents jet ventilation --> need to hook up to pipeline/wall inlet

Question 50

What does the common gas outlet do? What is the standard that is required of it?

Answer 50

Receive all gases from machine & delivers mixture to circuit --> pt Standard: Must be difficult to disconnect

Question 51

Why should you NOT use the CGO for supplemental oxygen? (2)

Answer 51

1. Delays emergencies -->if you need to start ventilating a patient gonna have to put it back together 2. Potential delivery of inhalation agents

Question 52

The alternate oxygen control in the low pressure system of the pneumatic system does what? What happens when you push the button......

Answer 52

Delivers oxygen in case of electronic power failure The rest of the machine turns off.. do not push the button.

Question 53

Which system in the pneumatic system has the most parts?

Answer 53

Intermediate system