Anesthesia machine ppt 2/ week 3 quiz Flashcards

1
Q

Master switch on the machine when it is in the off position what still works?

A

Flush valves and side gas ports are usually still functional in the Off position

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

only thing that tells you the percentage of O2 in the line?

A

Oxygen analyzer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

When the concentration of oxygen falls below 19%

A

it will kick off your ability to deliver nitrous.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Oxygen Pressure Failure Devices (OPFD) or Fail-Safe, what do they do?

A

Detects pressure drops (not concentration), thus with a construction cross over the pressure may be maintained with a mixed in gas but the concentration is not right.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Fail-safe systems DO NOT prevent

A

Hypoxic mixtures

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Fail safe system activated when?

A

Activated if the oxygen pressure falls below 20 to 25 psi

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the Bowman’s whistle?

A
Pneumatic alarms (aka Bowman’s Whistle): Uses a pressurized canister that is filled with oxygen when the anesthesia machine is turned on.  When the oxygen pressure falls below a certain value, the alarm directs a stream of oxygen through a whistle(in the intermediate system)
This alarm heard when machine first turned on and turned off.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Because of the fail-safe device, a decrease in N2O flow (with the N2O flowmeter bobbins dropping to zero) may actually be the first sign of

A

loss of oxygen supply pressure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Fail-safe valves do not prevent administration of a hypoxic mixture because

A

they depend on pressure and not flow.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

UPSTREAM-means

A

that you are heading toward the 02 source-pipeline or tank

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

DOWNSTREAM-means

A

you are heading toward the patient.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Oxygen flush valve?

A

Designed to minimize accidental activation(recessed button)

Used to fill bellows or ambu bag will dilute gases as pushed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

oxygen flush valve May not increase or decrease the pressure at the outlet of a vaporizer (give me a percentage)

A

by more than 20%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Oxygen flush valve works whether the machine is on or off, what else does it do?

A

Bypasses the flow meters and vaporizers and delivers gas directly to the common gas outlet

Be careful when using it!

Can cause barotrauma

Can dilute your anesthetic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what percent oxygen given with the flush valve?

A

100%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

oxygen flush valve activated during inhalation or exhalation?

What happens if activated during the wrong time?

A

exhalation only.

If activated during INSPIRATORY phase-the ventilator relief valve is closed, (so excess volume cannot go to scavenge system) and the excess volume goes to the patient!

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

which knob has to be different than the other knobs?

A

The oxygen knob has to be different than the other knobs

typically larger and fluted.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

The APL valve has two functions.

A

It limits the maximum pressure during manual ventilation

And exhausts excess gas into the scavenger system during manual and spontaneous ventilation.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

APL valve, turning it clockwise or counterclock wise, one way increases pressure and the other decreases pressure, which is which?

A

Counterclock wise decreases pressure

Clockwise increases pressure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

APL valve functions only when?

A

only when the ventilator is in Manual/Spontaneous mode

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

While the ventilator is on should the APL valve be on or off?

A

While the ventilator is on it is suggested that the APL valve be turned to zero, thus you are not able to cause any trauma by accident by delivering too much pressure.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Adjustable limits of the APL valve?

A

0-70 cm H2O

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What marks the end of the intermediate system, and the beginning of the low pressure system?

A

Needle of the flow-meter.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

low pressure system is down stream from?

A

the flow control valves-which allow gas into the flowmeters

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Flow tubes are called what kind of tube?
the larger size of the tube is which end?
Is every flowmeter designed for a diff gas?

A

Thorpe tube

distal end is larger in size, larger at top

Yes, every flowmeter is designed for a different gas, they are not interchangeable.
Bc every gas has a different density and viscosity.

26
Q

why is the top/distal end of the Thorpe tube larger?

A

being larger at the distal end makes it to were you have to use more gas to advance the float upwards and thus you have a correct reading of gas flow.

27
Q

Does a reading of 4 or 6 require more gas flow?

A

6, bc it is higher in the thorpe tube.

28
Q

What are flow indicators calibrated at?

if you are in a hyperbaric chamber what happens and if you are in Denver what happens?

A

calibrated at room temp (20 C) and atmospheric pressure (sea level 760 torr)

hyperbaric= higher pressure system than sea level, thus the machine will deliver less gas than is indicated bc there is more pressure.

Denver it will deliver more gas than is indicated bc there is less pressure.

29
Q

At low flow how does the gas flow?

A

Laminar, flow follows a parallel line of high pressure to low pressure.

30
Q

In laminar flow where is the most resistance?

A

resistance is near the sides of the tube, more flow towards the middle.

31
Q

What are the two key components in regards to gas flow?

A

viscosity vs density

32
Q

What is viscosity?

A

how easily the arrangement of the gas molecules are changed.

33
Q

What is density?

A

how many gas molecules are within a certain area.

34
Q

low flow is more important to what (property of gas) and high flow is more important to what (property of gas)

A

low flow- Viscosity

high flow - Density

35
Q

At high flows, with shorter and wider constriction, flow is more turbulent and dependent on?

A

density of the gas

36
Q

where do you read a bobbin from?

A

top flat part of the float

37
Q

where do you read a ball float from?

A

middle of the ball

38
Q

Where are oxygen flowmeters supposed to be in the united states?

A

furthest to the right

39
Q

oxygen always enters the common manifold?

A

downstream of other gases.

40
Q

Even when the O2 thorpe tube is turned off why does it still not touch the bottom of the tube?

A

a quarter of a L of 02 is still flowing through the machine, the float will not touch the bottom of the tube bc this is the amount that a person needs to live, safety feature.

41
Q

what should you make sure is turned off before turning the machine on? (most fragile part of the machine)

A

Make sure the flow meters are shut/turned off before you turn on the ventilator.

42
Q

The gas furthest down stream needs to be?

A

oxygen

43
Q

What is the ratio in the ohmeda link 25

what min. concentration of 02 does it prevent?

A

minimum 1:3 ratio of oxygen to nitrous oxide.

Ohmeda link 25 does not let an oxygen concentration of less than 25%

44
Q

Oxygen gear has how many teeth and nitrous oxide has how many gears?

A

29 teeth for oxygen

14 teeth for nitrous oxide

45
Q

The gears will not help with?

A

construction gas crossover

46
Q

Flow indicators are calibrated at what temp and pressure?

A

room temp and atm pressure

47
Q

which gear is larger and which is smaller?

A

Oxygen gear is larger and NO2 is smaller

48
Q

Use of an oxygen analyzer is mandatory if you are using how many gases?

A

if you are using a 3rd inert gas

49
Q

Again, what is the only thing that can detect a hypoxic mixture in any machine?

A

oxygen analyzer

50
Q

leaks in the piping section may not exceed how many ml/min?

A

30ml per min at 30 psi. 30 is ok, 31 is not.

51
Q

vaporizer interlock mechanism does what?

A

safety mechanism that allows ONLY one vaporizer at a time to be open.

52
Q

female connections are how many mm and male connections are how many mm?

A

15mm female

22mm male

53
Q

Double-circuit means

A

that a pneumatic force compresses a bellows, which empties its contents (gas from flowmeters and vaporizer) into the patient.

54
Q

What does a Piston do?

A

A piston has gas compressed within it, raising the pressure, which causes gas to flow into the patients lungs.

55
Q

Thus a piston ventilator?

A

uses no driving gas, and may be used without depleting the oxygen cylinder in case of oxygen pipeline failure

56
Q

Most machines today are what kind of bellow and why?

A

Most machines today are ascending bellows, because if you have a disconnect the bellow will stop working. Thus when there is a disconnect you have an alarm that tells you visually – hey this does not look right.

57
Q

What are the two types of bellows?

A
Ascending bellows (standing) ascend during expiration. 
and descending bellows(hanging) descend during expiration.
58
Q

Two most important factors to reduce anesthetic waste?

A

Scavenger and operating room ventilation

59
Q

scavenging systems may be ——- or ——?

A

active (suction applied) or passive (waste gases proceed passively down corrugated tubing through the room ventilation exhaust grill of the OR)

60
Q

Hazards of scavenging?

A

Barotruama or inability to ventilate

occupational exposure.

61
Q

Should you check the scavenger system daily?

A

Yes
There aredefinitehazards to patients when scavenging systems fail- so consider the scavenger part of the breathing system and check it each day. The smell of gas during a case is abnormal and the cause should be sought.