Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Apex Review > Anesthesia machine 3 > Flashcards

Anesthesia machine 3 Flashcards

1
Q

In the context of Thorpe tube flow dynamics, a low fresh gas flow will favor a ________ flow pattern

A

laminar

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

At a higher fresh gas flow, the annular space acts like an orifice, creating a _________ flow pattern

A

turbulent

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

Laminar flow is dependent on

A

gas viscosity (Poiseuille equation)

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

Turbulent flow is dependent on

A

gas density (graham’s law)

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

You are administering air 1 L/min and oxygen 3 L/min. Calculate the fraction of inspired oxygen.

A

80%

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

Describe how to calculate the FiO2 when using a flowmeter.

A

FiO2= (air flow rate x 21) + (oxygen flow rate x 100)/ total flow rate

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

Describe how to calculate fIo2 when using a nasal cannula.

A

add 4% FiO2 for every liter of O2 administered (up to a max of 44% FiO2 at 6 L/min)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

You are using an anesthesia machine that couples fresh gas flow to tidal volume and fully compensates for circuit compliance. Calculate the total tidal volume delivered to the patient.
oxygen= 3 L/min.
air = 1 L/min.
I:E= 1:2
bellows= 500 mL
RR= 10 bpm

A

632 mL

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

What is the tidal volume delivered to the patient equation?

A

Vt set on ventilator + FGF during inspiration- volume lost to circuit compliance

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

In flow-coupled anesthesia machines, changes in _________________ impacts the total tidal volume delivered to the patient.

A

respiratory rate, I:E ratio, FGF, and the height of the bellows

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

If an anesthesia machine does not couple FGF to tidal volume, then

A

what’s set on the ventilator is what’s delivered to the patient

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

Older anesthesia machines couple FGF to the tidal volume set on the ventilator which

A

may lead to errors in predicted Vt and minute ventilation

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

Vent changes that increase delivered tidal volume include

A

decreased RR
increased I:E ratio (from 1:2 to 1:1)
increased FGF
increased bellows height

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

Vent changes that decrease delivered tidal volume include

A

increased RR
decreased I:E ratio
Decreased FGF
decreased bellows height

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

Increasing the FGF will increase

A

tidal volume
minute ventilation
and peak inspiratory pressure
should see EtCo2 decrease

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

Decreasing the FGF will decrease

A

tidal volume
minute ventilation
peak inspiratory pressure
should see EtCo2 increase

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

A ventilator is programmed to deliver a tidal volume of 600 mL. If the breathing circuit compliance is 5 mL/cm H2O and the peak pressure is 25 cmH2O, what is the total tidal volume delivered to the patient?
a. 425 mL
b. 450 mL
c. 475 mL
d. 500 mL

A

c. 475 mL

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

Define compliance.

A

compliance is a change in volume for a given change in pressure- it’s a measure of distensibility

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

What is the compliance equation?

A

compliance= volume/pressure

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

Many modern ventilators ________________ for fresh gas lost to circuit compliance.

A

automatically compensate

21
Q

When the ventilator produces pressure inside the breathing circuit, some of this gas causes the circuit to expand. Since this doesn’t reach the patient,

A

it doesn’t contribute to the tidal volume that the patient receives

22
Q

Compliance is a measure of

A

distensibility

23
Q

The isoflurane dial is set to 2%. What percent of fresh gas exiting the vaporizing chamber is saturated with isoflurane?

A

100%

24
Q

When you consider the variable bypass vaporizer, think

A

variable bypass, flow-over, temperature compensated, out-of-circuit, and agent-specific

25
Q

Describe what out of circuit means.

A

the variable bypass vaporizer is positioned outside of the breathing circuit

26
Q

Describe what is meant by variable bypass.

A

when fresh gas enters the vaporizer, some of it encounters the liquid anesthetic while the rest bypasses the liquid anesthetic.

27
Q

With a variable bypass vaporizer, by setting the concentration on the dial, you determine

A

the splitting ratio (i.e. how much fresh gas contacts the liquid anesthetic)

28
Q

Describe what is meant by flow-over.

A

As the fresh gas enters the vaporizing chamber (liquid anesthetic is here), it flows over a series of baffles and wicks.

29
Q

Baffles and wicks increase _________ & _______________

A

surface area and turbulence

30
Q

Baffles and wicks ensure that fresh gas inside the vaporizing chamber becomes

A

100% saturated with the anesthetic agent

31
Q

Variable bypass vaporizers _______________ at changes in elevation

A

automatically compensate vaporizer output

32
Q

Describe agent-specific.

A

Each vaporizer is calibrated to one anesthetic agent- filling a vaporizer with the incorrect anesthetic can lead to catastrophic errors in output

33
Q

Describe temperature-compensated.

A

The temperature compensating valve adjusts the ratio of vaporizing chamber flow to bypass flow and guarantees a constant vaporizer output over a wide range of temperatures

34
Q

Setting a higher concentration directs more fresh gas towards _____________

A

the liquid anesthetic

35
Q

Setting a lower concentration directs

A

less fresh gas towards the liquid anesthetic

36
Q

Flows less than _________ or greater than __________ can lead to reduced vaporizer output

A

200 mL/min or greater than 15 L/min.

37
Q

If the vaporizer is tipped over some of the liquid anesthetic may enter

A

the bypass chamber leading to increased vaporizer output

38
Q

1 mL of liquid anesthetic produces _________ of anesthetic vapor

A

200 mL

39
Q

If the vaporizer is tipped, then you should run a high FGF through it for

A

20-30 minutes before it can be used for a patient

40
Q

The pumping effect can

A

increase vaporizer output

41
Q

Anything that causes gas that has already left the vaporizer to re-enter the vaporizing chamber can cause

A

the pumping effect

42
Q

The pumping effect is enhanced by

A

low fresh gas flows, low concentration dial setting, low levels of liquid anesthetic in the vaporizing chamber, positive pressure ventilation, and the use of the oxygen flush valve

43
Q

The pumping effect is minimized by

A

modern vaporizer design

44
Q

The most common cause of a vaporizer leak is

A

a loose filler cap

45
Q

The most common location for a leak to occur in the low-pressure system is

A

an internal leak in the vaporizer

46
Q

A leak can only be detected when

A

the vaporizer is turned off

47
Q

What is the equation to calculate how much liquid anesthetic is used?

A

mL of liquid anesthetic used per hour= Vol% x FGF (L/min) x3

48
Q

Setting the vaporizer to __________ eliminates the worry of tipping the vaporizer during transport or removal

A

transport mode (T)

Apex Review (224 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions