Brainscape's Knowledge GenomeTM

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


See full index

physiology IV > Ventilation and Lung Volumes > Flashcards

Ventilation and Lung Volumes Flashcards

1
Q

What effect does increasing lung compliance have on FRC?

A

It increases FRC

-not able to expel as much air

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

What happens to lung compliance with age?

A

it decreases

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

What is total lung capacity? What is the normal value?

A

max volume of gas that the lungs can contain

6-7 L

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

What is the tidal volume? What is the normal value?

A

Volume of gas which flows into and then out with each breath

-500-600 mL

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

How can tidal volume be increased?

A

exercise

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

can tidal volume be measured by a spirometer?

A

Yes

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

What is inspiratory reserve volume?

A

max volume of gas that can be inhaled from end-tidal inspiratory position

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

What is expiratory reserve volume?

A

-volume of gas that can be exhaled from end-tidal expiratory position

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

What is residual volume?

A

volume of gas contained in the lungs after max force of expiration
-can’t be exhaled

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

What is vital capacity?

A

-max volume of gas that can be exhaled after normal inspiration

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

What is inspiratory reserve capacity? (IC)

A

max volume of gas that can be inhaled from resting expiratory position

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

What is the formula for vital capacity ?

A

VC= IRV +Vt + ERV = TLC- RV

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

What is the formula for IC?

A

IC= VT+IRV = TLC - FRC

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

What is functional residual capacity?

A

Volume of gas in the lungs after normal expiration

-when diaphragm and chest muscles are relaxed

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

Can FRC be measured by a spirometer?

A

NO - it includes RV

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

What is the ultimate goal of using a N2 washout?

A

You want to measure FRC

  • can’t measure with a spirometer
  • this value is a good indicator of obstructive or restrictive diseases
17
Q

What are the steps involved in N2 washout ?

A
  1. subject breathes normal air
    - N2 fraction is measured
  2. at the end of eupneic breathing - lung is at FRC and subject breathes in 100% O2
    - for at least 7 minutes
    - washes out all N2 from the lung
  3. expired gas is collected in spirometer
18
Q

What is the issue with using N2 washout to record FRC?

A
  • if there are regions in the lung with trapped air, this volume won’t be measured
  • FRC is underestimated
19
Q

do we have to know the FRC equation for N2 washout, or the pletysmograph equation ????

A

not sure, making this flash card to remind us to memorize them if need be

20
Q

What is a plethysmograph?

A

a gas-tight chamber in which a patient sits in and breathes through a tube leading to outside
-used to measure FRC

21
Q

As a patient expires against a pressure transducer with a closed valve in a pletysmograph, what happens to their lung volume and P?

A
  • the volume of the lung is compressed

- the P of the lung is raised

22
Q

Since the chamber is gas tight, what happens to the air in the box outside the subject’s body as they breathe air to the outside?

A
  • the air will expand

- this change in volume is exactly equal to the amount of compression of air in the lungs

23
Q

What is the amount of dead space in mL approximated as ?

A

equal to the subject’s weight in pounds

24
Q

What is total ventilation equal to?

A

Dead space ventilation plus alveolar ventilation

25
Q

Hypoventilation results in what two consequences?

A
  1. alveolar hypercapnea - inc PACO2

2. hypoxia - dec PAO2

26
Q

Hyperventilation results in what two consequences?

A
  1. alveolar hypocapnea - dec PACO2

2. hyperoxia - inc PAO2

27
Q

Increasing oxygen consumption, has what effect on alveolar oxygen?

A

decreases it

28
Q

What does R mean in the equation:

PAO2=PlungO2-PACO2/R

A

-ratio of O2 consumption to production

29
Q

Vt is about what percentage of TLC?

A

only about 10%

-volume of air going into and out of the lung with each breath = small fraction of air in the lung

30
Q

About by how much do the PO2 and PCO2 oscillate by in alveoli during eupnea?

A

1-2 mmHg

31
Q

Why does the PO2 first decrease when you first inspire?

A

O2 is going into blood when air is going through the dead space

32
Q

What is a single breath analysis of dead space?

A

-subject inspires air containing neglible CO2 and then exhales into a spirometer
-fraction of CO2 is measured
(contains CO2 from the body)

33
Q

As the subject exhales, what does the FECO2 rise to and plateau at?

A

5%

34
Q

Why when the patient first exhale, does the first gas contain negligibly low CO2?

A

gas comes from the anatomic dead space

35
Q

What does the time of the midpoint of the rise of FECO2 correspond to?

A

the time at which all of the dead space air would be expired
-if there was a sharp boundary btwn dead space gas and alveolar gas

36
Q

What does the alveolar ventilation equation predict?

A

It describes the dependence of alveolar and arterial Pco2 on alveolar ventilation

37
Q

What does the alveolar gas equation predict?

A

Predicts the alveolar Po2, based on the he alveolar Pco2

physiology IV (40 decks)

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