RESPIRATORY: 594 - 596

Question 1

What are the two parts of the respiratory tree?

Answer 1

Conducting zone and respiratory zone

Question 2

What makes up the conducting zone?

Answer 2

1. Large airways: nose, pharynx, larynx, trachea, and bronchi
2. Small airways: bronchioles and terminal bronchioles

Question 3

How are the terminal bronchioles arranged and why?

Answer 3

Large numbers in parallel giving minimal airway resistance

Question 4

What is the function of the conducting zone?

Answer 4

Warms, humidifies, and filters air

Question 5

What does it mean that the conducting zone is “anatomic dead space”?

Answer 5

Does NOT participate in gas exchange

Question 6

How far do the cartilage and goblet cells extend in the conducting zone?

Answer 6

To the end of the bronchi

Question 7

Describe the epithelia in the conducting zone.

Answer 7

Pseudostratified ciliated columnar cells extend to the beginning of the terminal bronchioles, then transition to cuboidal cells

Question 8

In general, how far do the airway smooth muscles extend?

Answer 8

To the end of the terminal bronchioles

Question 9

What makes up the respiratory zone?

Answer 9

Lung parenchyma: respiratory bronchioles, alveolar ducts, alveoli

Question 10

Why is most of the epithelia in the conducting zone ciliated?

Answer 10

To beat mucus up and out of the lungs

Question 11

What is the function of the respiratory zone?

Answer 11

Gas exchange

Question 12

Describe the epithelia in the respiratory zone.

Answer 12

Mostly cuboidal cells in the respiratory bronchioles then simple squamous cells up to alveoli

Question 13

Is the epithelia in the respiratory zone ciliated?

Answer 13

No

Question 14

What do alveolar macrophages do?

Answer 14

Clear debris and participate in immune response

Question 15

What are the three types of pneumocytes?

Answer 15

1. Type I
2. Type II
3. Club (Clara) cells

Question 16

What is the main function of Type I vs. Type II pneumocytes?

Answer 16

Type I - Line the alveolar surfaces and allow for gas diffusion

Type II - Secrete pulmonary surfactant, also serve as precursors to Type I and Type II cells

Question 17

How are type I pneumocytes optimized for gas diffusion?

Answer 17

Squamous cells that are thin

Question 18

What is pulmonary surfactant made of?

Answer 18

Complex mix of lecithins - most important of which is dipalmitoylphosphatidylcholine

Question 19

What is the term for alveolar collapse?

Answer 19

Atelectasis

Question 20

Explain the Law of Laplace.

Answer 20

Alveoli have an increased tendency to collapse on expiration as the radius decreases

Question 21

Why do we need pulmonary surfactant?

Answer 21

Decreases alveolar surface tension and prevents alveolar collapse

Question 22

Which cells proliferate during lung damage?

Answer 22

Type II

Question 23

When does surfactant synthesis begin?

Answer 23

Around week 26 of gestation, but mature levels are not achieved until around week 35

Question 24

What is an indicator of fetal lung maturity?

Answer 24

Lecithin-to-sphingomyelin ratio > 2.0 in amniotic fluid

Question 25

Describe club/clara cells.

Answer 25

Nonciliated, low-columnar/cuboidal with secretory granules

Question 26

What are 3 functions of club cells?

Answer 26

1. Secrete component of surfactant 2. Degrade toxins 3. Act as reserve cells

Question 27

How many lobes does each lung have?

Answer 27

Right - 3 | Left - 2

Question 28

What is the homologue of the right middle lobe?

Answer 28

Lingula - it is a projection of the upper lobe of the left lung

Question 29

Why is the right lung a more common site for inhaled foreign body?

Answer 29

Right main stem bronchus is wider and more vertical than the left

Question 30

Describe the difference in location of where an aspirated item will likely end up while a person is upright vs. supine.

Answer 30

Will tend to end up regardless in the right inferior lobe Upright - lower portion Supine - superior portion

Question 31

Describe the relationship between the location of the pulmonary artery to the bronchus on each side.

Answer 31

RALS - Right anterior Left superior

Question 32

At what levels do the IVC, esophagus, and aorta pass through the diaphragm?

Answer 32

Mnemonic: I (IVC) ate (8) ten (10) eggs (esophagus) at twelve (12). IVC - T8 Esophagus - T10 Aorta - T12

Question 33

What nerve innervates the diaphragm and what are its roots?

Answer 33

Phrenic nerve - C3, 4, 5 | Mnemonic: C3, 4, 5 keep the diaphragm alive

Question 34

Where can pain from diaphragm irritation be referred to?

Answer 34

Shoulder (C5) and the trapezius ridge (C3, 4)

Question 35

What is inspiratory reserve volume (IRV)?

Answer 35

Air that can still be breathed in after normal inspiration

Question 36

What is tidal volume (TV)?

Answer 36

Air that moves into lung with each quiet inspiration

Question 37

What is the normal value for tidal volume?

Answer 37

Around 500 mL

Question 38

What is expiratory reserve volume (ERV)?

Answer 38

Air that can still be breathed out after normal expiration

Question 39

What is residual volume?

Answer 39

Air in lung after maximal expiration

Question 40

Which lung volume cannot be measured on spirometry?

Answer 40

Residual volume

Question 41

What is the difference between volume and capacity?

Answer 41

Capacity - made up of 2 or more volumes

Question 42

What are the components of inspiratory capacity (IC)?

Answer 42

IRV + TV

Question 43

What is functional residual capacity (FRC)?

Answer 43

Volume in lungs after normal expiration

Question 44

What are the components of FRC?

Answer 44

RV + ERV

Question 45

What is vital capacity (VC)?

Answer 45

Maximum volume of gas that can be expired after a maximal inspiration

Question 46

What are the components of VC?

Answer 46

TV + IRV + ERV

Question 47

What is total lung capacity (TLC)?

Answer 47

Volume of gas present in lungs after a maximal inspiration

Question 48

What are the components of TLC?

Answer 48

IRV + TV + ERV + RV

Question 49

What makes up physiologic dead space (VD) in the respiratory system?

Answer 49

Anatomic dead space of conducting airways plus functional dead space in alveoli (volume of inspired air that does not take part in gas exchange

Question 50

What is the largest contributor of functional dead space?

Answer 50

Apex of healthy lung

Question 51

How do we calculate VD?

Answer 51

VD = VT x (PaCO2 - PECO2) / (PaCO2) ``` PaCO2 = arterial PCO2 PECO2 = expired air PCO2 ``` Mnemonic: Taco, Paco, Peco, Paco

Question 52

What are two measures of ventilation?

Answer 52

1. Minute ventilation | 2. Alveolar ventilation

Question 53

What is minute ventilation?

Answer 53

Total volume of gas entering the lungs per minute

Question 54

How do we calculate minute ventilation?

Answer 54

VE = VT x respiratory rate (RR)

Question 55

What is alveolar ventilation?

Answer 55

Volume of gas per unit time that reaches the alveoli

Question 56

How do we calculate alveolar ventilation?

Answer 56

VA = (VT - VD) x RR