L33 & 34

Question 1

What is tidal volume (Vt)?

Answer 1

The volume of air entering or leaving the lungs during a single breath. Includes the volumes that fills the alveoli and the what fills the airway.

Question 2

What is the inspiratory reserve (IRV)?

Answer 2

Additional volume inspired above Vt, used when exercising

Question 3

What is the expiratory reserve volume (ERV)?

Answer 3

Additional volume expired below Vt.

Question 4

What is residual volume (RV)?

Answer 4

Volume of gas left in lungs after maximal forced expiration. Cannot be measured by Spirometry

Question 5

What is inspiratory capacity?

Answer 5

Vt + IRV

Question 6

What is the functional reserve capacity?

Answer 6

Volume of air in the lungs at the end of normal passive expiration or normal Vt (ERV+ RV)

Question 7

What is vital capacity? What changes it?

Answer 7

Volume expired after maximal inspiration (IC+ ERV)

• Increases with male gender, increased body size, and physical conditioning.
• Decreases with age

Question 8

What is total lung capacity?

Answer 8

Sum of all 4 lung volumes. The maximum volume of air that the lungs can hold

Question 9

What increases the RV/TLC ratio?

Answer 9

Obstructive lung disease (by increasing RV) and restrictive lung disease (by decreasing TLC)

Question 10

What is forced expiratory volume in one second (FEV1) used for?

Answer 10

To differentiate between lung diseases

Question 11

How is physiologic dead space calculated?

Answer 11

VD= Vt (PaCO2 - PECO2/ PaCO2)

Question 12

What is the average diet RQ?

Answer 12

0.8

Question 13

What produces the intrapleural fluid?

Answer 13

Parietal pleura

Question 14

What is the function of the conducting zone?

Answer 14

To bring air into and out of the respiratory zone

-Warms, humidifies, and filters air before it reaches gas exchange.

Question 15

What are the mucous secreting cells?

Answer 15

Goblet cells

Question 16

What does SNS activation do to airway diameter and resistance?

Answer 16

Increased diameter, decrease resistance

Question 17

What does PNS activation do to airway diameter and resistance?

Answer 17

Decreased diameter and increased resistance

Question 18

What is the Ficks law of diffusion?

Answer 18

The amount of gas moving across a tissue is proportional to the area but inversely proportional to its thickness

Question 19

What are the pores of Kohn?

Answer 19

Pores in the walls of alveoli that allow airflow between adjacent cells.

Question 20

What are the two types of alveolar cells and what do they do?

Answer 20

• Type 1: wall forming

- Type 2: surfactant producing

Question 21

What are the two layers that facilitate mucociliary transport?

Answer 21

The sol fluid layer and the gel fluid layer

Question 22

What regulates the sol fluid layer?

Answer 22

-Regulated by cAMP/calcium chloride channels (CFTR)

Question 23

What is ciliary dyskinesia?

Answer 23

Recessive genetic disorder that results in defect in gene encoding for dynein, which compromises mucociliary clearance

Question 24

Typically, forced viral capacity (FVC) is expired in **.

Answer 24

3 seconds

Question 25

Normally, FEV1/FVC = ***. What does this mean?

Answer 25

0.8 80% of the VC can be forcibly expired in the 1st second

Question 26

How does fibrosis affect FEV1 and FVC?

Answer 26

It decreases both, however FVC has a greater decrease. Therefore FEV1/FVC is increased.

Question 27

How does asthma affect FEV1 and FVC?

Answer 27

Both are decreased, however FEV1 has a greater decrease. Therefore, FEV1/FVC is decreased.

Question 28

What is the difference between anatomic and physiologic dead space?

Answer 28

Anatomic dead space is the conducting zone, physiologic dead space is the total volume of the lungs not participating in gas exchange.

Question 29

What are the two ways that ventilation relate can be expressed, including the equations.

Answer 29

-Minute ventilation Minute ventilation = Vt x breaths/min -Alveolar ventilation: Alveolar ventilation= (Vt-Vd) x breaths/min Vd= physiologic dead space

Question 30

What is the alveolar ventilation equation?

Answer 30

Va= (VCO2 x K)/ PACO2 VCO2= rate of CO2 production

Question 31

What does increased alveolar ventilation mean for PACO2?

Answer 31

It is decreased.

Question 32

What happens to alveolar ventilation when CO2 production is doubled?

Answer 32

It must also double and the curve shifts to the right

Question 33

What are the two alternate methods to measure FRC since it cannot be measured by spirometry?

Answer 33

-Helium dilution and body plethysmograph