Questions Derived From BRS Phys

Question 1

Volume of lungs that does not participate in gas exchange

May be greater than anatomic dead space in lung dz w/ ventilation/perfusion defects

Answer 1

Physiologic dead space

Question 2

The sum of tidal volume and inspiratory reserve volume is

Answer 2

Inspiratory capacity

Question 3

Alveolar pressure minus intrapleural pressure

Answer 3

Transmural pressure

Question 4

The major site of airway resistance is?

Answer 4

Medium size bronchi

Question 5

Parasympathetic stimulation, irritants, and the slow-reacting substance of anaphylaxis (asthma) ______ the airways, _______ the radius, and _______ the resistance to airflow

Answer 5

Constrict

Decrease

Increase

Question 6

Sympathetic stimulation and sympathetic agonists (isoproterenol) _____ the airways via beta-2 receptors, _______ radius, and _______ resistance to airflow

Answer 6

Dilate

Increase

Decrease

Question 7

High lung volumes are associated with greater traction on airways and _______ airway resistance

Answer 7

Decreased

Question 8

______ are associated w/ less traction and increased airway resistance, even to the point of airway collapse

Answer 8

Low lung volumes

Question 9

Intrapleural pressure can be measured by ?

Answer 9

A balloon cath in the esophagus

Question 10

Obstructive disease in which expiration is impaired

Characterized by decreased FVC, FEV1, and FEV1/FVC ratio.

Air that should have been expired is not, leading to air trapping, increased FRC

Answer 10

Asthma

Question 11

Obstructive dz w/ increased lung compliance in which expiration is impaired

Decreased FVC, FEV1, FEV1/FVC ratio.

Increased FRC

Barrel chest

Pink puffers or blue bloaters

Combo of chronic bronchitis and emphysema

Answer 11

COPD

Question 12

COPD type

Mild hypoxemia, maintained alveolar ventilation

Normocapnia

Primarily emphysema

Answer 12

Pink puffers

Question 13

COPD type

Severe hypoxemia

Do not maintain alveolar ventilation so they become hypercapneic

Right ventricular failure and systemic edema.

Cyanosis

Answer 13

Blue bloaters

Question 14

Restrictive dz w/ decreased lung compliance in which inspiration is impaired

Decreased in all lung volumes.

FEV1/FVC may be increased or normal

Answer 14

Fibrosis

Question 15

Lung diffusing capacity increases during exercise because:

Answer 15

There are more open capillaries and thus more SA for diffusion

Question 16

For a perfusion-limited process, diffusion of gas can be increased only if the _________ increases

Answer 16

Blood flow

Question 17

Perfusion-limited exchange is what O2 does in ____________ conditions

Answer 17

Normal

Question 18

Diffusion limited exchange is what O2 does in

Answer 18

Emphysema, fibrosis, strenuous exercise

Question 19

In _________, the gas does not equilibriate by the time blood reaches the end of the pulmonary capillary

Answer 19

Diffusion-limited exchange

Question 20

Hemoglobin increases O2 carrying capacity of blood by

Answer 20

70 fold

Question 21

Causes sickle cell disease

The alpha subunits are normal and the beta subunits are abnormal

In deoxygenated form, makes sickle shaped rods that deform RBC’s

Answer 21

Hemoglobin S

Question 22

Right shifts for hemoglobin oxygen associated curve

Answer 22

Increase 2,3-DPG concentration

Increase temperature

Increase in pCO2

Decrease pH

Question 23

Left shifts on the hemoglobin-O2 dissociation curve

Answer 23

Increased affinity of hemoglobin for O2

CO poisoning

HbF

Decreased pCO2

Increased pH

Decreased temperature

Decreased 2,3 DPG concentration

Question 24

A normal A-a gradient is

Answer 24

Between 0 and 10 mmHg

Question 25

The A-a gradient is increased if ?

Answer 25

O2 doesn’t equilibriate between alveolar gas and arterial blood (diffusion defect, V/Q defect, R-L shunt) And PAO2 is greater than PaO2

Question 26

Pressures are ____ in pulmonary circulation than in the systemic circulation

Answer 26

Much lower

Question 27

Resistance is _____ in the pulmonary circulation than in the systemic circulation

Answer 27

Much lower

Question 28

When a person is supine, blood flow is _____ throughout the lung

Answer 28

Nearly uniform

Question 29

When a person is standing, blood flow is uneven. It is lowest at the _____ and hight at the ______

Answer 29

Apex Base

Question 30

Zone of lung Blood flow highest Arterial pressure > venous pressure > alveolar pressure

Answer 30

Zone 3

Question 31

Zone of lung Blood flow medium Arterial pressure > alveolar pressure > venous pressure

Answer 31

Zone 2

Question 32

Zone of lung Blood flow low Alveolar pressure > arterial pressure > venous pressure

Answer 32

Zone 1

Question 33

In the lungs, hypoxia causes vaso________

Answer 33

Constriction

Question 34

Hypoxia induced vasoconstriction is the opposite of effect of hypoxia in other organs (most organs, hypoxia —> vasodilation) what effect does this have?

Answer 34

Local vasoconstriction redirects blood from poorly ventilated, hypoxic regions of the lung and towards the well ventilated regions, where the blood can pick up more oxygen

Question 35

Fetal pulmonary vascular resistance is ______ because of ___________

Answer 35

Very high Generalized hypoxic vasoconstriction

Question 36

Right to left shunts always result in ? ?

Answer 36

A decrease in arterial pO2

Question 37

Left to right shunts do what to arterial pO2?

Answer 37

Do not result in decrease

Question 38

Ratio of alveolar ventilation (V) to pulmonary blood flow (Q)

Answer 38

V/Q ratio

Question 39

With normal breathing rate, tidal volume, and cardiac output, the VQ ratio is approximately ____ and arterial pO2 is _______ and arterial pCO2 is _______

Answer 39

0.8 100mmHg 40mmHg

Question 40

Ventilation and perfusion are both lowest at ____ and highest at _____, but there is more of a difference in perfusion

Answer 40

Apex Base

Question 41

V/Q ratio is higher at the ________ of the lung and lower at the ________ of the lung

Answer 41

Apex Base

Question 42

Regional differences in pO2 are ______ than regional differences for pCO2

Answer 42

Greater

Question 43

V/Q ratio in pulmonary embolism

Answer 43

infinite (dead space)

Question 44

V/Q ratio in airway obstruction

Answer 44

V/Q = 0

Question 45

Resistance to blood flow decreases as you go to the _______ of the lung

Answer 45

Bottom

Question 46

Perfusion is _______ in the top and _______ in the lowest part of the lung

Answer 46

Smallest Greatest

Question 47

Pulmonary vascular smooth muscle _______ in low pO2

Answer 47

Contracts

Question 48

How does COPD lead to right heart failure?

Answer 48

People w/ obstructive/restrictive lung dz. alveolar pO2 is low. So overall pO2 is low, causes the entire lung to vasoconstrict (normal response to low pO2) and this increases vascular resistance, making the right heart insufficient.

Question 49

What accounts for the only marginal increase in pulmonary artery pressure in exercise, with increased cardiac output?

Answer 49

1. Recruitment; opening up of previously closed arteries | 2. Distention; increase in the radius of the existing blood vessels which decreases resistance

Question 50

Resistance to blood flow through the alveolar vessels ________ as the alveoli expand because the alveolar vessels are longer and their radii are smaller

Answer 50

Increases

Question 51

Resistance is ______ to length

Answer 51

Directly proportional

Question 52

Resistance is ________ to radius to the fourth power

Answer 52

Inversely proportional

Question 53

Inhibits inspiration, therefore regulating inspiratory volume and respiratory rate. Inhibitory signals to apneustic center

Answer 53

Pneumotaxic center

Question 54

What stimuli increases breathing rate in peripheral chemoreceptors, but does not in central chemoreceptors

Answer 54

Decreased oxygen level

Question 55

The distribution of V/Q ratios is ________ during exercise than when at rest

Answer 55

More even | There is resulting decrease in physiologic dead space

Question 56

The volume remaining in the lungs after the expiration of a tidal volume

Answer 56

Functional residual capacity

Question 57

Flow rates from large airways are effort ____

Answer 57

Dependent

Question 58

Flow rates from small airways are effort _____

Answer 58

Independent