T2 Pulmonary Function Test

Question 1

What is the partial pressure of nitrogen in room air?

Answer 1

560mmHg

Question 2

What test is depicted in the graph below?

Answer 2

Nitrogen washout test

Question 3

What should a normal nitrogen concentration in the atmosphere be?

Answer 3

75 - 80 %

Question 4

What percentage nitrogen should a healthy 20 y/o have at 3 minutes into a nitrogen washout test?

Answer 4

2.5% in 3 min

Question 5

What is a normal reading on a nitrogen washout test?

Answer 5

2.5% in less than 7 min

Question 6

What is an abnormal reading on a nitrogen washout test?

Answer 6

2.5% in greater than 7 min

Question 7

Which of the two nitrogen washout tests below displays an abnormal and uneven air distribution?

Answer 7

Right graph

Question 8

How might V_D be estimated from the graph below?

Answer 8

V_D = phase I + ½(phase II)

Question 9

What lung volume comprises the entirety of phase I in the figure below?

Answer 9

V_D (Anatomical Dead Space)

Question 10

What lung volume(s) comprise phase II in the figure below?

Answer 10

Phase II = Transitional Phase = V_D + V_A air

Question 11

Where is air coming from in phase III in the figure below?
What is the nitrogen concentration of this air?

Answer 11

• All areas of the lungs
• [N₂] ≈ 20%

Question 12

What phase in a closing capacity/volume test is the longest for healthy people?

Answer 12

Phase III

Question 13

What causes the sharp upswing noted in Phase IV in the figure below?

Answer 13

Lung base small airways start to collapse so [N₂] starts to increase.

Question 14

In what area of the graph below will we notice excessive compliance?

Answer 14

Question 15

At what lung volume does inspiration start when conducting a closing volume/capacity test?

Answer 15

RV

Question 16

What is indicated by 1 in the figure below?

Answer 16

Closing Volume

Question 17

What is indicated by 2 in the figure below?

Answer 17

Residual Volume

Question 18

What is indicated by 3 in the figure below?

Answer 18

Closing Capacity

Question 19

What is indicated by 4 in the figure below?

Answer 19

Vital Capacity

Question 20

What lung capacity changes the most with age?

Answer 20

Closing Capacity

Question 21

At what age will closing capacity equate to functional residual capacity?
What does this mean?

Answer 21

• Age: 50
• CC = FRC means that the airways of the lung base collapse in normal respiration.

Question 22

Which lung capacities decrease with age?

Answer 22

• IC
• VC
• ERV

Question 23

Which lung capacities increase with age?

Answer 23

• FRC
• RV
• CC

Question 24

Where would closing volume be located on the graph below?

Answer 24

Question 25

Why are small airways more prone to collapse as we age?

Answer 25

Loss of traction

Question 26

If a full inspiration of FiO₂ 100% were taken from this lung in the graph below, where would [N₂] be more diluted?

Answer 26

Base of the lung due to having a lower starting volume of 20%. *someone check this one, the O₂ should theoretically go to the apex first since we're taking an inspiration from RV, right?*

Question 27

At what stage of the respiratory cycle would you expect a healthy person to have the best possible traction?

Answer 27

2 seconds into inspiration and right before expiration when the lungs are fullest. *Best traction at higher lung volumes.*

Question 28

Does traction increase or decrease as we get closer to RV?

Answer 28

Traction decreases

Question 29

How can vital capacity be determined from the graph below?

Answer 29

TLC - RV

Question 30

Would effort-dependent expiration occur at higher or lower lung volumes?

Answer 30

Effort-dependent expiration = TLC and higher lung volumes

Question 31

Would effort-independent expiration occur at higher or lower lung volumes?

Answer 31

Effort-independent expiration = RV and lower lung volumes

Question 32

In a healthy patient, what percentage of vital capacity expiration should occur in the first second of expiration?

Answer 32

80% of VC expired in 1st second of expiration.

Question 33

What is the forced expiratory flow rate in someone young and healthy?

Answer 33

10 L/s

Question 34

What causes the pathology noted by 1 in the figure below?

Answer 34

Emphysema → Loss of P_ER

Question 35

Which of the following curves would have the greatest degree of effort-independent expiratory flow?

Answer 35

1. Emphysema

Question 36

What are the peak expiratory flow rates of each of the curves below?

Answer 36

1. 8 L/s 2. 13 L/s 3. 10 L/s

Question 37

Does a forced expiration or a passive expiration present more of a risk for small airway collapse?

Answer 37

Forced Expiration

Question 38

When would small airway collapse be more likely?

Answer 38

COPD/Emphysema

Question 39

Loss of what capability would increase the risk of small airway collapse?

Answer 39

P_ER

Question 40

How does pursed-lip breathing prevent airway collapse?

Answer 40

Pursed-lip breathing will restrict outflow and increase airway pressures **Airway pressures > P_IP = no collapse**

Question 41

What causes the increased pressures seen in the rightmost figure below?

Answer 41

Contraction of intercostal muscles, accessory muscles, and abdominal muscles.

Question 42

Loss of _____ will result in more collapsible airways.

Answer 42

P_ER (Traction)