Exam 3 Anesthesia Machine I [7/8/24] Flashcards
1
Q
- What group oversees the standards of the anesthesia machine?
- When was this group founded?
A
- American Society for Testing and Materials
- Since 1979 (reapproved in 2005)
slide 2
2
Q
What should the anesthesia machine do?
A
- Provide Storage/shelving
- Provide a Housing for monitoring devices
- Provide Accurate and safe gas delivery
- Provide a Means for ventilating patients
- Provide Electrical outlets for things that the machine needs, not for external items
- Provide a place to prop your feet during long cases lol
SHAME on the anesthesia machine if it does not provide these things
slide 3
3
Q
What features of the anesthesia works if the Master Switch is OFF?
A
- All electronic functions disabled except:
- Oxygen flush valve is active
- Auxillary oxygen flowmeter
- Battery charger
- Electrical outlets
Only ABE! works when the machine is OFF
Oh BAE
slide 4
Still have to have things plugged in if it is off for these things to work
4
Q
What features of the Anesthesia Machine work when the master switch is on?
A
- Pneumatic and electrical functions
- activates alarms and safety features
- power-up protocol can be bypassed
Everything should be on and working
slide 4
5
Q
Things to know about the power failure indicator
A
- Will be visual or audible
- Keep the machine plugged in
- battery backup at the highest level
- Duration of backup depends on power usage
- manual ventilation vs ventilation
slide 5
6
Q
for the power failure indicator what is the primary indicator visual or audible?
A
- visual is the primary indicator
- ideally we want both visual and audible
S5- lecture
7
Q
What is the best way to save power on your ventilator if you lose power during an operation?
A
- Switch from control ventilator to manual ventilation
S5-lecture
8
Q
how do we know the power failure/battery life of machine?
A
S6
9
Q
anesthesia machine should always be plugged into a red outlet, why?
A
- this is the hospitals backup
- all critical machines should be plugged into the red outlet
S7
If plugged into the white outlet, when the power goes out so the does the anesthesia machine.
10
Q
What are the electrical outlets on the anesthesia machine used to power?
What kind of stuff can be plugged in?
A
- Power the Anesthesia monitors
- Used for add on monitors like BIS, CO.
- If requirements exceed outlet; circuit breaker will activate
slide 8
11
Q
Can bair huggers, suction machines, x-rays machines be plugged into the electrical outlet on anesthesia machne?
A
- No, other appliances should be plugged into hospital’s main outlets
S8
12
Q
What are the 3 parts of the pneumatic system?
A
- High Pressure
- Intermediate Pressure
- Low Pressure
slide 9
13
Q
Click here for the picture of the pneumatic system
A
- everything on the left side is high pressure
- circles are the canisters of gases on the back of machine
- arrows are check valves
- middle is intermediut
- right is low presure system
- flow meeters
- vaporizers
- common gas outlet
slide 10-lecture
14
Q
Where does the high-pressure system recieve gas from? At what pressure?
A
- Receives gas from cylinders
- at HIGH, VARIABLE pressure of 2200 psi
slide 11
15
Q
How does the high pressure system reduce the pressure to a lower more constant pressure?
A
- Uses the pressure regulator (1st stage regulator) to reduce to a lower more constant pressure
slide 11
16
Q
In a high pressure system the pressure is reduced by a pressure regulator. What is the pressure reduced to?
A
- Reduced to 45 psi [from 2200 PSI]
S11
17
Q
Without pressure regulators what would we constantly be changing?
A
- flow meters
- this is not efficient, not time friendly, and not cost friendly*
S11
18
Q
What is the purpose of pressure regulators?
A
- Reduce high, variable pressure in cylinders to lower constant pressure for the machine.
- One pressure regulator must be present for each cylinder
Andy
Pressure regulators are also called reducing valves
19
Q
What is the purpose of the Hanger Yoke?
A
- Orients and support the cylinder
- Provide a gas-tight seal
- Ensures unidirectional flow
OPE
slide 12/13
20
Q
With a hanger yoke, how many “o” rings do you use?
A
- only use one
- if you use 2 the pin index safety system (PISS) could be bypassed
S12-lecture
21
Q
It is required to have at least one hanger yoke for ____ and one hanger yoke for ____?
A
- 1 for oxygen
- 1 for nitrous
S13
22
Q
What are the parts of the Hanger Yoke?
A
- Body- principle framework
- Retaining screw- tightens cylinder (clamp)
- Nipple- thru which gas enters the machine
- Index pins- prevents attaching an incorrect cylinder (PISS)
- Washer- forms seal between cylinder and yoke
- Check valve assembly- ensure unidirectional flow
slide 14
23
Q
What is the purpose of the check valve assembly of the hanger yoke?
A
- Prevent gas from exiting the machine when there is no cylinder in the yoke
- Prevent gas from being transferred from a cylinder with higher pressure to one with lower pressure (if both are in a yoke and ON)
Ensures Unidirectional Flow
slide 15/16
24
Q
How does check valve assembly work?
A
- Either coiled spring or valve seat that allows to get around or occlude gas flow.
- Coiled Spring:
- Collpased –> gas gets around
- Open –> occludes gas flow
- Valve Seat:
- Lifted valve –> air gets around
S16
25
Cylinder pressure indicator must be present for what?
* must be present for each gas supplied by cylinders
| slide 17
26
What are Bourdon Tubes?
What do they do?
* curved hollow tubes
* working mechanism for analogue pressure devices
* pressure changes ↑/↓ curve
* motion is transmitted to gauge
| S17
27
The cylinder pressure indicator gauge is required to be calibrated in what?
* kilopascals kPA]
* *may also be in psi*
| S17
28
What were the components of the high-pressure system?
* Cylinder
* Pressure Reducing Valve
* Bourdon Guages
* Hanger Yoke
**C**an **P**ressure **B**e **H**igh
| S11-18
29
Where does the intermediate system receive gas from/ get its pressure from?
* Receives gases from the pressure regulator or pipeline
| slide 19
30
The intermediate pressure system receives gases from the pressure regulator or pipeline. What is the psi from these?
* 1st pressure regulator: 45 psi
* pipeline: 50-55 psi
| S19
31
What is the intermediate pressure system pressure if the master switch is OFF?
* 0 mmHg
| slide 19
32
What is included in the intermediate pressure system?
* **P**neumatic part of the master switch
* **F**low control valves
* **P**ipeline inlet connections
* **O**xygen pressure failure devices
* **O**xygen flush valve
* **P**iping
POOF PP
**P F**or **POOP**
| slide 19
33
What is the pipeline inlet connection?
* The entry point for gases from the pipelines.
* *Pipeline inlet connects are fitted with a diameter index safety system (DISS)*
| slide 21
34
The anesthesia machines are required to have pipeline inlets for what gases?
* Required: Oxygen and Nitrous
* Most also have air
* *inlets are fitted with DISS*
| slide 21
35
Pipeline Inlet connections must conatin what to prevent the anesthesia machine gas from returning to the pipeline?
* Unidirectional check valve
| slide 21
36
Where is the pipeline pressure indicator located?
* Found on the front of the anesthesia machine
* indicator is required for each gas monitored
| slide 23
## Footnote
Picture next to the pressure indicator signifies whether gas is from the pipeline or cylinder.
37
Pipeline pressure indicators:
* indicator must be where?
* What do newer machine have?
* Indicator must be on pipeline side
* if downstream and cylinder valve open will have adequate pressure reading until cylinder is 0/empty
* digital and newer machines have LED
| slide 23
38
The intermediate system contains piping.
* What is the function of piping?
* What must piping be able to withstand?
* Function: The piping connects the components inside the machine
* Must be able to withstand 4x the intended pressure (about 200 psi)
| slide 25
39
With piping, leaks must not exceed ____ ml/min inside the anesthesia machine.
* 25 ml/min
| slide 25
40
How does the oxygen failure safety device work?
* If O2 pressure is reduced to 30 psi, other gases like nitrous will decrease or discontinue to maintain at least 19% O2 concentration at the common gas outlet.
* this continues until O2 flow ceases - simulated in machine check
| slide 26
41
O2 failure alarm will sound within ____
5 seconds
| slide 26
42
* What two places does the oxygen flush get its supply?
* Where does it send O2?
* Receives oxygen from pipeline inlet or cylinder pressure regulator
* sends O2 to common gas outlet
| slide 27
43
What are the standards for the oxygen flush?
* Have **f**low between 35-75 L/min (can cause barotrauma)
* Designed to **m**inimize accidental use
* Must be **o**perable with 1 hand
* **S**ingle purpose
* **S**elf-closing
Flush MOSS
| slide 27
44
What are the hazards of using the oxygen flush?
* **If stuck on, could cause:**
* Barotrauma
* Awareness
| slide 28
45
What is the function of the flow adjustment control?
* Regulate the flow of oxygen, air, and other gases
* Mechanical or electrical
* **Must be only one control for each gas; must be adjacent to its flowmeter**
| slide 30
46
What is unique about the oxygen flow knob?
* It must be fluted and larger than other gases (looks and feels different)
| slide 30
47
What kind of pressure does the low Pressure system have? What is this dependent on?
* Pressure is slightly above atmospheric and variable
* Depends on flow from flowmeters and backpressure from breathing circuit
| slide 32
48
What are the components of the low-pressure system?
* Flowmeters
* Hypoxia prevention devices
* Unidirectional valves (within the machine)
* Pressure relief devices
* Common gas outlet
UP CHF
PH(F)UC
| slide 32
49
Where is the low-pressure system located?
* located downstream from flow control devices (knobs)
| slide 32
50
What indicates the rate that gas passes through?
* Flowmeter
| slide 34
51
What is the Thorpe tube?
* Flowmeters have a Thorpe tube- vertical glass tube design
* Smallest diameter at bottom
* Free floating indicator
* A stop at top of tube
* A flow scale
| slide 34
52
What are the flowmeter requirements?
* Must be marked with appropriate color and chemical symbol
* 2nd stage regulator maintains 14-30psi
* Gases empty into a common manifold
| slide 34
53
what does the 2nd stage regulator do?
What does the 1st stage regulator do?
* 2nd stage regulator: Maintains flows at 14-30psi
* 1st stage regulator: at the cylinder to drop pressure to 45 PSI
| S34- lecture
54
30 psi is important. What alarm goes off here?
* At 30 PSI is where the O2 pressure alarm occurs.
| S34 - lecture
55
What is the flowmeter sequence?
Which comes 1st with Drager flowmeter & Ohmeda/Daytex?
* Normal gas flow from:
* bottom to top
* Left to right
* Drager: N2O
* Ohmeda: Air
| slide 36
56
What is the standard for the flowmeter sequence?
* The standard requires **oxygen** flowmeter to be placed on the **right** side.
* *By having the O2 flowmeter on the right, there is the least chance of leaking and being hypoxic*
| slide 36
57
Which is the safe option in flowmeter sequence?
* C or D becuase O2 is at the end
* in A or B if there is a leak up stream pt risk not getting O2
| S37-lecture
58
What are the hypoxia prevention devices?
* Mandatory Minimum Oxygen Flow
* Minimum Oxygen Ratio
| slide 38
59
For the mandatory minimum oxygen flow:
* What is the minimum flow?
* When is it activated?
* Minimum of 50 to 250 ml/min flow
* Master switch needs to be ON for mandatory minimum oxygen flow to work.
| slide 38
60
What is the minimum oxygen ratio?
* Gas ratio between oxygen and nitrous uses **mechanical linkage with nitrous**
* Link engages when oxgyen concentration is 25%.`
| slide 38
## Footnote
-doesn’t allow you to give all nitrous without turning oxygen on
-doesn’t allow you to turn O2 down to 0 with nitrous going on
-when O2 concentration drops to ~25% the link between nitrous and oxygen engages and when the oxygen goes down, it will pull down the nitrous also
-if you hit the 25% concentration mark —> there’s a mechanism in there that lets it disengage/fall off or engage and tighten up to where youre turning on both of them
61
Where are the unidirectional valves located in the low-pressure system?
* Located between the vaporizer and common gas outlet.
* Upstream from oxygen flush valve.
| slide 40
62
What is the function of low-pressure unidirectional valves?
* Unidirectional valves will lessen the back pressure from flush or breathing circuit
* Prevents back pumping /pumping effect
| slide 40
63
- Pressure relief devices are located where?
- what do they do with excess pressure?
* Near common gas outlet
* Opens to atmosphere and vents if preset pressure is exceeded
| slide 41
64
What is the drawback to the pressure relief device of the low-pressure system?
* Limits the ability of the machine to provide adequate jet ventilation
Jet ventilation = sending jets of O2 or air
| slide 41
65
What component receives all gases from the machine and delivers the mixture to the circle system?
* Common gas outlet
| S42/43
66
The Common Gas outlet must be what?
must be difficult to disconnect
| slide 42
67
The common gas outlet should not be used for what? Why?
* Common gas outlet should not be used for **supplemental oxygen** because:
* it can cause delay in emergencies
* and if used during emergencies, potential delivery of inhalation agents to the patient
| slide 42
68
What can deliver oxygen in case of an electronic power failure?
* Alternate Oxygen Control
| slide 44
69
What happens if you press the on/off button on the alternative oxygen control?
* If you press this button, everything shuts off except for O2.
* this is for when there is an emergency and you need volatiles and everything else off and just need to deliver O2
| S44- lecture
