Brainscape's Knowledge GenomeTM

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


See full index

Pulmonology > Pulmonary Function > Flashcards

Pulmonary Function Flashcards

1
Q

What are the three main components of PFTs?

A

spirometry (how air exits and enters) lung volume diffusion capacity

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

What are three ways of determining lung volumes?

A
  1. helium dilution 2. nitrogen washout 3. body plethysmography
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

How does helium dilution lung volume testing work?

A

Helium is inhaled and allowed to equilibrate. decrease in concentration is compared to previous concentration and volume, to calculate for new volume (of the lung)

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

What equation is used to determine lung volume during body plethysmography?

A

boyles law P1 V1 = P2V2

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

What would be characteristic of lung volumes in obstructive diseases?

A

hyperinflation

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

Why does emphysema increase lung volumes?

A

loss of elastic recoil elevates RV, while airway collapse traps gas on exhalation

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

Why does chronic bronchitis and asthma cause increased lung volumes?

A

Increased airway resistance traps air and causes hyperinflation

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

What is responsible for the decrease in lung volumes in restrictive diseases?

A

INcreased elastic recoil (decreased compliance) decreases lung volume

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

What is true of lung volumes in restrictive diseases?

A

they are decreased

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

What is the volume that patients are asked to inhale on spirometry?

A

total lung capacity

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

What is the volume that patients are asked to exhale to during spirometry?

A

RV

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

What value is generated from the difference between inhaled volumes and exhaled volumes in spirometry?

A

the forced vital capacity = TLC - RV

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

In normal individuals, how long does it take to reach FVC in spirometry?

A

~ 4 seconds

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

What is a normal FEV1?

A

~75%

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

In health, what is the ratio of FEV1 to FVC?

A

75% or 0.75

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

As you age, what happens to FEV1/FVC?

A

the ratio drops

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

When there is expiratory obstruction, what happens to FEV 1 and FVC?

A

FEV1 drops more than FVC, lowering FEV1/FVC

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

Why does FEV1 drop in obstructive lung disease?

A

FEV1 drops because of decreased lung elastic recoil pressure or increased airflow resistance

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

What accounts for the fact that FEV1 tends to drop more than FVC in obstructive disease?

A

patients compensate by exhaling longer to reach the same FVC

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

What do restrictive defects do to FEV1 and FVC?

A

drop both of them

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

Although FEV1 and FVC drop in restrictive disease, what happens to flow?

A

Flow at any given point will be higher (isovolume flow)

22
Q

Why is isovolume flow higher than normal in restrictive defects?

A

they may be higher than normal because elastic recoil pressure is higher and airway resistance is lower than normal i.e. exhalation is shorter than normal and FEV1/FVC may increase

23
Q

Although FEV1 and FVC both drop in restrictive diseases, FEV1/FVC can increase. Why?

A

exhalation is shorter and isovolume flow is higher, so the ratio of FEV1 to FVC is higher

24
Q

Can you tell asthma and COPD apart on spirometry alone?

A

no, unless you compare pre and post bronchodilator and see improvements in FEV1 and/or FVC

25
Q

What type of conditions elevate DLCO?

A

DLCO is elevated in disorders resulting in increased hemoglobin in areas of intact ventilation (e.g.: alveolar hemorrhage and polycythemia)

26
Q

What effect does alveolar hemorrhage have on DLCO?

A

increases it

27
Q

What effect does polycythemia (from chronic hypoxemia, for example) have on DLCO?

A

increases it

28
Q

What type of conditions decrease DLCO?

A

decreased when ventilation does not match perfusion (i.e. low V/Q) or when there is loss of blood (anemia) or functional blood vessels (pulmonary embolism, emphysema, interstitial lung disease)

29
Q

What does a low V/Q do to DLCO?

A

Decreases it

30
Q

What does anemia do to DLCO?

A

decreases it

31
Q

What does pulmonary embolism do to DLCO?

A

Decreases it

32
Q

What does emphysema do to DLCO?

A

decreases it

33
Q

What does ILD do to DLCO?

A

decreases it

34
Q

How do you calculate inspiratory capacity?

A

TLC - FRC

35
Q

How do you calculate the expiratory reserve volume?

A

FRC - RV

36
Q

how do you calculate theinspiratory reserve volume?

A

IC-TV

37
Q

Where is TLC found on the flow volume curve?

A

on the X axis, where you shift from inspiration to expiration

38
Q

What does the width of the flow volume curve correspond to?

A

the FVC

39
Q

What is suggested by a flattened inspiratory loop on the flow volume curve?

A

Flattening of the inspiratory loop suggests inadequate strength, effort or technique during the forced inhalation maneuver, or upper airway obstruction (eg, vocal cord dysfunction, epiglottitis, laryngeal edema, and laryngeal malignancy).

40
Q

Which side of the flow volume loop is asymmetric: expiratory or inspiratory?

A

expiratory

41
Q

Why is the expiratory part of the flow volume loop asymmetric?

A

The normal expiratory loop is asymmetric because higher expiratory flows are generated at larger lung volumes. This is because at higher lung volumes lung elastic recoil pressure (Pel) is greater (like stretching a sponge or rubber band) and airway resistance is lower as the inflated lung “pulls” airways open via the tethering effects of alveoli.

42
Q

What are the two determinants of maximal expiratory flow?

A

flow = Pel/Rus

Where Pel: elastic recoil pressure

Rus: resistance distal to the equal pressure point

43
Q

Why is Ppl (pleural pressure) not part of the equation for maximum flow in the flow volume loop?

A

Ppl, which is related to effort, is not a part of this equation; thus the concept of effort independence of maximal airflow: expiratory flow is independent of effort

44
Q

How are expiratory flow rates related to lung volume?

A

at higher lung volumes, expiratory flow rates are higher

45
Q

what does the obstructive defect look like on the time volume curve?

A

A ramp

46
Q

What does restrictive disease look like on the volume time curve?

A

a rectangle

47
Q

Expiratory airflow is decreased most by what combination of pathophysiologic conditions?

a) low Pel and high Raw
b) high Pel and high Raw
c) low Pel and low Raw
d) high Pel and low Raw

A

a) low Pel and high Raw

b) high Pel and high Raw
c) low Pel and low Raw
d) high Pel and low Raw

48
Q

Emphysema is best characterized by:

a) high FEV1/FVC
b) hyperinflation with low DLCO
c) high Pel and low Raw
d) fixed inspiratory and expiratory airflow obstruction

A

a) high FEV1/FVC

b) hyperinflation with low DLCO

c) high Pel and low Raw
d) fixed inspiratory and expiratory airflow obstruction

49
Q

. Isovolume airflow is high in:

a) asthma
b) vocal cord paralysis
c) pulmonary fibrosis
d) pulmonary embolism

A

a) asthma
b) vocal cord paralysis

c) pulmonary fibrosis - restrictive disease

d) pulmonary embolism

50
Q

Which of the following test results suggests asthma?

  1. Low FEV1/FVC that normalizes after albuterol
  2. Low FEV1/FVC with low diffusing capacity
  3. Normal FEV1/FVC after an irritant challenge
  4. Normal FEV1/FVC with low diffusing capacity
A
  1. Low FEV1/FVC that normalizes after albuterol
  2. Low FEV1/FVC with low diffusing capacity
  3. Normal FEV1/FVC after an irritant challenge
  4. Normal FEV1/FVC with low diffusing capacity
51
Q

Flattening of the inspiratory loop suggests:

a) asthma
b) vocal cord paralysis
c) pulmonary fibrosis
d) pulmonary embolism

A

a) asthma

b) vocal cord paralysis

c) pulmonary fibrosis
d) pulmonary embolism

Pulmonology (35 decks)

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