Brainscape's Knowledge GenomeTM

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


See full index

Patient Monitoring and Instrumentation > Principles of the Anesthesia Machine Part 2 > Flashcards

Principles of the Anesthesia Machine Part 2 Flashcards

1
Q

An anesthetist is running 6L/min Air, 3L/min N2O, and 1L/min O2. What is the FiO2?

A

22.6%

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

An anesthetist is running 3L/min of air and 0.5L/min of oxygen. What is the patient’s FiO2?

A

32.3%

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

What is vapor pressure?

A

the pressure a vapor exerts above the liquid in a closed container

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

What is latent heat of vaporization?

A

when the liquid evaporates it loses heat (gets cold)

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

What is the vaporizer dial?

A

It determines the concentration of the agent that is delivered to patient

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

An anesthetist is delivering straight Air and 6% Desflurane to a patient. What is the patient’s FiO2?

A

19.74%

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

An anesthetist is delivering 1L/min O2, 1L/min N2O, and 2% Sevoflurane. What is the FiO2?

A

49%

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

What is variable bypass?

A

some of the FGF gases bypass the vaporizer

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

What volatile agents have variable bypass?

A

Isoflurane and Sevoflurane

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

What volatile agent doesn’t have variable bypass? What happens instead?

A

Desflurane; a percentage of Des joins the FGF gases

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

What is special about Desfluranes vaporizer?

A

It is pressurized and heated; Des has a high vapor pressure and would lose heat and it’s ability to vaporize without this special vaporizer

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

What are the volatile agent safety features?

A

1-color
2-safety interlock system (one on at a time)
3- keyed filler adapter (only can put it in correct vaporizer)

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

How does the machine control pressure in vent mode?

A

The ventilator has its own APL valve, relieves pressure at the end of expiration

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

What could a leak in the bellows of the ventilator lead to (2)?

A

1- higher than expected PIP

2- Higher than expected FiO2

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

Would you prefer your ventilator to have descending (hanging) bellows or ascending (standing) bellows? Why?

A

Ascending bellows because you can better diagnose a leak in the bellow. (No gravity to help open it up)

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

What is compliance?

A

The ability of a container to expand when pressure is added to it. (old balloon [high] vs. new balloon[low])

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

What are the units of pulmonary compliance?

A

mL/cmH2O

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

What is the equation for pulmonary compliance?

A

change in volume (mL)/change in pressure (cmH2O)

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

What is pulmonary elastic recoil (elasticity)?

A

the ability of a container to return to the original volume after the pressure has been released

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

Fill in the blank:

High compliance means _____ elasticity.

A

low

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

What type of patients would have high compliance?

A

COPD patients, smokers (easy inhale, hard exhale)

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

What type of patients would have low compliance?

A

acute respiratory distress syndrome (hard inhale, easy exhale)

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

A patient’s pulmonary compliance is 20mL/cmH2O. They are being ventilated with positive pressure ventilation (PPV) on a ventilator with 30cm/H2O pressure. What is the patient’s tidal volume?

24
Q

A patient on a ventilator is receiving a tidal volume of 600 mL. The inspiratory pressure waveform is shown. What is the patient’s dynamic lung compliance in mL/cmH2O?

A

30mL/cmH2O

25
Q

What are the 5 common ventilator settings?

A 
1- Tidal volume (Vt)
2- Respiratory Rate (RR)
3- Inspiratory:Expiratory Ratio (I:E)
4- Peak Inspiratory Pressure (PIP)
5- Positive End Expiratory Pressure (PEEP)
26
Q

What is a normal Vt?

27
Q

What is a normal RR?

28
Q

What is a normal I:E?

A

1:2 (smokers/COPD= 1:2.5)

29
Q

What is a normal PIP?

A

35-40cm/H2O for ETT

30
Q

What is a normal PEEP?

A

~5cm/H2O (if used)

31
Q

Why use PEEP?

A

To keep a small volume in the lungs after expiration to keep alveoli open and prevent atelectasis.

32
Q

What is CPAP?

A

Continuous positive airway pressure; constant PEEP

33
Q

When do you (anesthesia) use CPAP?

A

preoxygenation for obese patients

34
Q

What are the common uses for CPAP?

A

1-sleep apnea
2-patients intubated for long periods of time
3-intubated patients getting lung surgery
4-preoxygenation for obese patients

35
Q

A patient is being ventilated with a ventilator in the operating room. The respiratory rate is 10, and the I:E ratio is 1:2. How long is each inspiration/expiration for this patient?

A

2sec inspiration; 4sec expiration

36
Q

A patient is being ventilated with a ventilator in the operating room. The respiratory rate is 6, and the I:E ratio is 1:4. How long is each inspiration/expiration for this patient?

A

Each breath is 10. 2, 8 respectively

37
Q

A patient is being ventilated with a ventilator in the operating room. The respiratory rate is 3, and the I:E ratio is 1:3. How long is each inspiration/expiration for this patient?

A

Each breath is 20. 5, 15 respectively

38
Q

A patient is being ventilated with positive pressure ventilation on the ventilator. Their respiratory rate is 8 and their minute ventilation reads 3.2L. What is their tidal volume?

39
Q

A 35 year old, 85kg male patient is undergoing a laparoscopic hiatal hernia repair in the operating room. They are being mechanically ventilated. The fresh gas flow and ventilator settings are as follows:
RR= 10, I:E Ratio= 1:2, FGF= 2L/min air and 1L/min O2
How much FGF is entering the circuit during each inspiration?

40
Q

A patient is receiving mechanical ventilation with the following parameters:
RR= 10, Vt= 300mL, I:E Ratio= 1:2
What is the inspiratory flow rate in L/min?

41
Q

A patient is receiving mechanical ventilation with the following parameters:
RR: 4, Vt= 600mL, I:E Ratio= 1:2
What is the expiratory flow rate in L/min?

42
Q

What is the Valsalva Maneuver?

A

forced exhalation against a closed glottis

43
Q

What are the three results of a Valsalva Maneuver?

A
  • increased intrathoracic pressure
  • decreased venous return
  • decreased arterial blood pressure
44
Q

How can a patient do their own valsalva maneuver?

A

bearing down or blowing through a straw

45
Q

What is a valsalva maneuver for?

A

it is a vagal response to terminate a tachyarrhythmia known as supraventricular tachycardia (SVT)

46
Q

Under general anesthesia we can deliver a valsalva maneuver by?

A
  • close APL valve
  • deliver positive pressure via bag
  • hold pressure for several seconds at 30-40cm/H2O
47
Q

Why would we do a valsalva maneuver (3)?

A

1- treat atelectasis
2- lung leak (lung surgery)
3- dura leak (neurosurgery)

48
Q

What is volume control ventilation?

A

We set the Vt that the machine will deliver no matter what pressure (assuming no Pressure limit is set)

49
Q

Let’s say that an anesthetist sets a tidal volume of 900mL for me, and it generated a peak inspiratory pressure (PIP) of 28cm/H2O. What would you expect to happen to the peak inspiratory pressure if I were 300lbs heavier, had my abdomen insufflated with CO2 for a laparoscopic surgery, and/or was placed in the Trendelenburg position?

A

It would still deliver 900mL, but the PIP would INCREASE

50
Q

Suppose an anesthetist ventilated their previous patient with 700mL tidal volumes. The next patient is 2-years old. On this 2 year old, the anesthetist turns on the ventilator without remembering to lower the tidal volume. What’s gonna happen?

A

It would still deliver 700mL, and the kids lungs would “blow up”

51
Q

What is pressure control ventilation?

A

we set the Pinspired (pressure inspired)

52
Q

What is the advantage of pressure control ventilation?

A

You will never exceed the pressure set

53
Q

What are the disadvantages of pressure control ventilation?

A

1- don’t know immediately the Vt that will be given

2- Vt will change as things in surgery change (trendelenburg; laparoscopic)

54
Q

An anesthetist is using volume control when ventilating a patient. Vent settings are as follows:
RR= 8, Vt= 700mL, PIP= 30cm/H2O
If the anesthetist increases the respiratory rate to 12, what will happen to the patients Vt and PIP?

A

Tidal volume (Vt)? Unchanged

Peak Inspiratory Pressure (PIP)? Increase, same volume must go in over a shorter period of time; vent must push faster/harder

55
Q

An anesthetist is using pressure control when ventilating a patient. Vent settings are as follows:
RR= 8, Vt= 550mL, PIP= 25cm/H2O
If the anesthetist increases the respiratory rate to 12, what will happen to the patients Vt and PIP?

A

Tidal volume (Vt)?
Decrease, bc the ventilator has to push it in faster/harder, the PIP is reached sooner; the lungs have less time to expand
Peak Inspiratory Pressure (PIP)?
Unchanged

56
Q

An anesthetist is using volume control when ventilating a patient. Vent settings are as follows:
PIP= 25cm/H2O ,Vt= 550,I:E= 1:2
If the I:E ratio is changed to 1:3, what will happen to the patient’s Vt and PIP?

A 
Tidal volume (Vt)?
Unchanged 
Peak Inspiratory Pressure (PIP)?
Increase, shorter time to deliver the Vt
57
Q

An anesthetist is using pressure control when ventilating a patient. Vent settings are as follows:
PIP= 25cm/H2O ,Vt= 550,I:E= 1:2
If the I:E ratio is changed to 1:1, what will happen to the patient’s Vt and PIP?

A 
Tidal volume (Vt)?
Increase; inspiratory time is longer and more volume is able to get in 
Peak Inspiratory Pressure (PIP)?
Unchanged

Patient Monitoring and Instrumentation (24 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions