Respiratory System: Mechanical Properties Of The Lung And Chest Wall: Static And Dynamic Flashcards
0
Q
Composed of two or more volumes
A
Capacity
1
Q
Total volume of air that can be contained in the lung
A
Total lung capacity (TLC)
2
Q
Many lung volumes are measured with a
A
Spirometer
3
Q
Volume of air that is moved with each quiet breathing
A
Tidal volume
4
Q
Total volume of exhaled air, from a maximal inspiration to a maximal exhalation
A
Vital capacity
5
Q
Is the air remaining in the lung after complete exhalation
A
Residual volume
6
Q
Is the sum of VC and RV
A
Total lung capacity (TLC)
7
Q
Volume of air that can be moved
A. Vital capacity
B. Residual volume
C. Tidal volume
A
A. Vital capacity
8
Q
Volume of air that is always present
A. Vital capacity
B. Residual volume
C. Tidal volume
A
B. Residual volume
9
Q
Is the volume of air in the lung at the end of exhalation during quiet breathing
A
Functional residual capacity (FRC)
10
Q
Is composed of residual volume (RV) and expiratory reserve volume (ERV)
A
Functional residual capacity (FRC)
11
Q
The volume of air that can be exhaled from functional residual capacity (FRC) to residual volume (RV)
A
Expiratory reserve volume
12
Q
Ratio used to distinguish different types of diseases
A
RV / TLC ratio
In normal individuals - usually less than 0.25
13
Q
Elevated RV/TLC ratio, secondary to an increase in RV out of proportion to any increase in TLC is seen in individuals with
A
Obstructive pulmonary diseases
14
Q
An elevated RV/TLC ratio caused by a decrease in TLC occurs in individuals with
A
Restrictive lung diseases
15
Q
T or F
In the absence of external forces the lung will become almost airless.
A
T, 10% of TLC
16
Q
In the absence of the lung parenchyma, the volume of the chest wall is approximately (?)% of TLC
A
60
17
Q
Lung volumes are determined by the balance between the (1) and the (2)
A
(1) lung’s elastic properties
(2) properties of the muscles of the chest wall
18
Q
The maximum volume of air within the lung and chest wall is controlled by the muscles of (inspiration / expiration).
A
Inspiration
19
Q
As the muscles lengthen, their ability to generate force (increases / decreases)
A
Decreases
20
Q
Occurs when the inspiratory chest wall muscles are unable to generate the additional force to further distend the lung and chest wall
A. VC
B. FRC
C. TLC
A
C. TLC
21
Q
T or F
Minimal volume of air in the lung (i.e. RV) is controlled by inspiratory muscle force.
A
F, expiratory muscle force
22
Q
Occurs when expiratory muscle force is insufficient to further reduce chest wall volume
A. Vital capacity
B. Residual volume
C. Tidal volume
A
B. Residual volume
23
Q
Is determined by the balance between inward recoil and outward recoil
A. VC
B. FRC
C. TLC
A
B. FRC
24
T or F
| When the chest muscles are weak, FRC increases (lung elastic recoil < chest wall muscle force)
F, decreases (lung elastic recoil > chest wall muscle force)
25
In the presence of airway obstruction, FRC (increases / decreases)
Increases
26
True about lung compliance
A. Is a measure of the elastic properties of the lung
B. Is a measure of how easily the lung is distended
C. Is defined as the change in lung volume resulting from 1-cm H2O change in the distending pressure of the lung
D. B and C
E. All are true
E. All are true
27
(High / Low) lung compliance refers to a lung that is readily distended
(High / Low) lung compliance is a lung that is not readily distended
High
| Low
28
T or F
| The compliance of a normal human lung is always about 0.2 L/cm H2O regardless of lung volume.
F, not always because it varies with lung volume
29
The lung is (more or less) distensible at high lung volumes
Less
30
True about emphysema except
A. An obstructive lung disease
B. Disease usually of smokers
C. Destruction of alveolar septa and pulmonary capillary bed
D. Lung is noncompliant
E. Every 1-cm H2O increase in pressure, the increase in volume is greater than in normal
D. Lung is non compliant
It is compliant
31
True about pulmonary fibrosis except
A. Restrictive lung disease
B. Increased collagen fiber deposition in interstitial space
C. Lung is noncompliant
D. Every 1-cm H2O increase in pressure, the increase in volume is greater than in normal
E. All are true
D. Every 1-cm H2O increase in pressure, the increase in volume is greater than in normal
The increase in volume is less
32
Separates the lung and the chest wall
Pleural space
33
Pressure changes across the lung and across the chest wall are defined as
Transmural pressure
34
Is defined as the pressure difference between the alveolar pressure and the pleural pressure
A. Transpulmonary pressure
B. Transmural pressure across the chest wall
C. Pressure across the respiratory system
A. Transpulmonary pressure
35
The lung requires (positive / negative) transpulmonary pressure to increase its volume, and the lung volume (increases / decreases) with increasing transpulmonary pressure
Positive, increases
36
T or F
| The lung is totally devoid of air when the transpulmonary pressure is zero
F, is not totally devoid of air because of the surface tension-lowering properties of surfactant
37
Is the difference between pleural pressure and the pressure surrounding the chest wall
A. Transpulmonary pressure
B. Transmural pressure across the chest wall
C. Pressure across the respiratory system
B. Transmural pressure across the chest wall
38
Pleural pressure is (positive / negative) relative to atmospheric pressure during quiet breathing, the transmural pressure across the chest wall is (positive / negative)
Negative, negative
39
Is the sum of the pressure across the lung and the pressure across the chest wall
A. Transpulmonary pressure
B. Transmural pressure across the chest wall
C. Pressure across the respiratory system
C. Pressure across the respiratory system
40
Transmural pressure across the respiratory system at FRC is
A. 0
C. =0
C. =0
41
T or F
The resting volume of the chest wall is the volume at which the transmural pressure for the chest wall is 0, and it is approximately 60% of TLC
T
42
At volumes greater than 60% of TLC, the chest wall is recoiling (inward / outward), whereas at volumes less than 60% of TLC, the chest wall is recoiling (inward / outward)
Inward, outward
43
T or F
| Further increases in transmural pressure produce significant change in volume
F, because the elastic limits of the lung have been reached - no change in volume
44
Is the sum of the pleural pressure and elastic recoil pressure of the lung
Alveolar pressure
45
Is the pressure distending the lung
Transpulmonary pressure
46
Is the pressure tending to collapse the lung
Elastic recoil pressure
47
T or F
| There is airflow in the absence of a pressure gradient
F, no airflow
48
- Is the volume of gas moved per unit of time
| - is equal to the volume of gas moved with each breath times the number of breaths per minute
Minute ventillation
49
Pleural pressure in normal individuals before inspiration begins is approximately
-5 cm H2O
50
The pressure in the pleural space is (positive / negative) relative to atmospheric pressure before inspiration begins.
Negative
51
T or F
Just before inspiration begins alveolar pressure is zero because with no gas flow, there is no pressure drop along the airways
T
52
When chest is opened the lungs recoils until the alveolar pressure pressure is (?) and the chest wall (increase / decrease) in size
Zero, increase
53
Laminar flow is present at (high / low) flow rates
Low
Parallel to the airway walls
54
Turbulence occurs at (higher or lower) flow rates
Higher
The flow is disorganized
55
Is the most important determinant of resistance
Radius of the tube
56
```
If the radius of a tube is reduced in half, the resistance will increase (?)-fold
A. 2
B. 4
C. 8
D. 16
```
D. 16
57
```
If length of the tube is increased 2-fold, the resistance will increase (?)-fold
A. 2
B. 4
C. 8
D. 16
```
A. 2
58
Resistance is (directly / inversely) proportional to the fourth power of the radius, and it is (directly / inversely) proportional to the length of the tube and to the viscosity of the gas
Inversely, directly
Berne and Levy Physiology p.436
59
```
In turbulent flow, gas movement occurs
A. Parallel to the axis of the tube
B. Perpendicular to the axis of the tube
C. Both a and b
D. None
```
C. Both parallel and perpendicular to the axis
60
Second major factor that determines rates of airflow in the airways
Airflow resistance
61
The major site of resistance along the bronchial tree
Large bronchi
62
T or F
| The smallest airway contribute very little to the overall resistance of the bronchial tree
T
63
Airflow velocity (increases / decreases) substantially as the effective cross-sectional area increases
Decreases
64
T or F
| Airway generations exist in series rather than in parallel
F, in parallel rather than in series
65
T or F
As airway diameter decreases, the resistance offered by each individual airway increases, but the large increase in parallel pathway reduces the resistance at each generation of branching
T
66
Airway resistance in healthy individuals is approximately
1 cm H2O/L sec
67
T or F
| Resistance to airflow decreases with increasing lung volume
T
68
Factors that increase airway resistance except
A. Mucus
B. Edema
C. Contraction of bronchial smooth muscle
D. Low density gas
D.
Gas density rises and results in an increase in airway resistance
69
A condition associated with increased airway resistance because of a combination of bronchospasm, airway inflammation and mucus
Status asthmaticus
70
Efferent vagal fibers (increases / decreases) airway resistance and (increases / decreases) anatomic dead space
Increases, decreases
71
Stimulation of sympathetic nerves and release of norepinephrine (stimulate / inhibit) airway constriction
Inhibit
72
Reflex stimulation of the vagus nerve result in airway (constriction / dilatation) and coughing
Constriction
73
- A derivative of acetylcholine
| - Used to diagnose airway hyperresponsivenes
Methacholine
74
Airway obstruction develops in patient with asthma at much (higher / lower) concentrations of inhaled methacholine
Lower
75
The total volume of air that is exhaled during a maximal forced exhalation from TLC to RV
Forced vital capacity (FVC)
76
The volume of air exhaled in the first second during the maneuver
FEV1
77
```
In normal individuals, (1)% to (2)% of the FVC can be exhaled in the first second
A. 65% - 70%
B. 70% - 75%
C. 75% - 80%
D. 80% - 85%
```
C. 75% - 80%
78
FEV1 / FVC ratio is (,=) 75% to 80% in normal adults
greater than
79
FEV1/FVC ratio less than 75% suggest
Difficulty in exhaling because of obstruction
80
As exhalation proceeds the resistive drop in pressure is (greater / less) than in normal individuals to that of individuals with lung disease.
Greater
81
In individual with lung disease, at the start of exhalation, the driving pressure for expiratory gas flow is (,=) in a normal individual.
=
82
Results in a less than maximal exhalation that is known as air trapping and produces an increase in lung volume
Premature airway closure
83
Popping sound usually heard during inspiration on auscultation
Crackles/ rales
84
T or F
| Crackles are due to closing of airways during inspiration that opened during the previous exhalation
F, opening of airways that closed
85
```
Crackles can be due to the ff except
A. Mucus accumulation
B. Airway collapse
C. Fluid in airways
D. None
```
B.
Airway inflamation
86
Acute and chronic lung diseases can change the expiratory flow-volume relationship by changes in the ff except
A. Static lung pressure
B. Airway resistance and distribution of resistance
C. Loss of mechanical tethering if intraparenchymal airways
D. All are correct
E. All are wrong
D.
+ changes in the stiffness or mechanical properties of the airways
+ differences in the severity of the aforementioned changes in various lung regions
87
Dynamic compliance is always (,=) than/to static compliance and it (increases / decreases) during exercise
<, increase
88
T or F
During tidal volume breathing, a small change in alveolar surface are is sufficient to bring additional surfactant molecules to the surface and the lung is more compliant
F, is insufficient , less compliant
89
During exercise there are (small / large) changes in the tidal volume and (more / less) surfactant material is incorporated into air-liquid interface
Large, more
90
T or F
| Sighing or yawning increase dynamic compliance by increasing tidal volume and restoring the normal surfactant layer
T
91
T or F
| The dynamic compliance of the chest wall is significantly different from its static compliance
F
92
Is required to overcome inherent mechanical properties of the lung
Work
93
Is the most common cause of respiratory failure
Respiratory muscle fatigue
94
Process in which gas exchange is inadequate to meet the metabolic needs of the body
Respiratory failure
95
True about obstructive lung disease except
A. Airway resistance is elevated
B. Greater negative pleural pressure is needed to maintain normal respiratory flow rates
C. Increase in total inspiratory work
D. Increase in negative pleural pressure pressure during exhalation
E. All are correct
D, Increase in positive pleural pressure
96
T or F
| Only individuals with lung disease adopt respiratory patterns that minimize the work of breathing
Both normal individuals and those with lung disease
97
```
Work of breathing is also increased when
A. Deeper breaths are taken
B. When respiratory rate decreases
C. Both are correct
D. None
```
A
Respiratory rate increases
98
T or F
Just before inspiration begins alveolar pressure is zero because with no gas flow, there is no pressure drop along the airways
T
99
When chest is opened the lungs recoils until the alveolar pressure pressure is (?) and the chest wall (increase / decrease) in size
Zero, increase
100
Laminar flow is present at (high / low) flow rates
Low
Parallel to the airway walls
101
Turbulence occurs at (higher or lower) flow rates
Higher
The flow is disorganized
102
Is the most important determinant of resistance
Radius of the tube
103
```
If the radius of a tube is reduced in half, the resistance will increase (?)-fold
A. 2
B. 4
C. 8
D. 16
```
D. 16
104
```
If length of the tube is increased 2-fold, the resistance will increase (?)-fold
A. 2
B. 4
C. 8
D. 16
```
A. 2
105
Resistance is (directly / inversely) proportional to the fourth power of the radius, and it is (directly / inversely) proportional to the length of the tube and to the viscosity of the gas
Inversely, directly
Berne and Levy Physiology p.436
106
```
In turbulent flow, gas movement occurs
A. Parallel to the axis of the tube
B. Perpendicular to the axis of the tube
C. Both a and b
D. None
```
C. Both parallel and perpendicular to the axis
107
Second major factor that determines rates of airflow in the airways
Airflow resistance
108
The major site of resistance along the bronchial tree
Large bronchi
109
T or F
| The smallest airway contribute very little to the overall resistance of the bronchial tree
T
110
Airflow velocity (increases / decreases) substantially as the effective effective cross-sectional area increases
Decreases
111
T or F
| Airway generations exist in series rather than in parallel
F, in parallel rather than in series
112
T or F
As airway diameter decreases, the resistance offered by each individual airway increases, but the large increase in parallel pathway reduces the resistance at each generation of branching
T
113
Airway resistance in healthy individuals is approximately
1 cm H2O/L sec
114
T or F
| Resistance to airflow decreases with increasing lung volume
T
115
Factors that increase airway resistance except
A. Mucus
B. Edema
C. Contraction of bronchial smooth muscle
D. Low density gas
D.
Gas density rises and results in an increase in airway resistance
116
A condition associated with increased airway resistance because of a combination of bronchospasm, airway inflammation and mucus
Status asthmaticus
117
Efferent vagal fibers (increases / decreases) airway resistance and (increases / decreases) anatomic dead space
Increases, decreases
118
Stimulation of sympathetic nerves and release of norepinephrine (stimulate / inhibit) airway constriction
Inhibit
119
Reflex stimulation of the vagus nerve result in airway (constriction / dilatation) and coughing
Constriction
120
- A derivative of acetylcholine
| - Used to diagnose airway hyperresponsivenes
Methacholine
121
Airway obstruction develops in patient with asthma at much (higher / lower) concentrations of inhaled methacholine
Lower
122
The total volume of air that is exhaled during a maximal forced exhalation from TLC to RV
Forced vital capacity (FVC)
123
The volume of air exhaled in the first second during the maneuver
FEV1
124
```
In normal individuals, (1)% to (2)% of the FVC can be exhaled in the first second
A. 65% - 70%
B. 70% - 75%
C. 75% - 80%
D. 80% - 85%
```
C. 75% - 80%
125
FEV1 / FVC ratio is (,=) 75% to 80% in normal adults
greater than
126
FEV1/FVC ratio less than 75% suggest
Difficulty in exhaling because of obstruction
127
As exhalation proceeds the resistive drop in pressure is (greater / less) than in normal individuals to that of individuals with lung disease.
Greater
128
In individual with lung disease, at the start of exhalation, the driving pressure for expiratory gas flow is (,,=) in a normal individual.
=
129
Results in a less than maximal exhalation that is known as air trapping and produces an increase in lung volume
Premature airway closure
130
T or F
Just before inspiration begins alveolar pressure is zero because with no gas flow, there is no pressure drop along the airways
T
131
When chest is opened the lungs recoils until the alveolar pressure pressure is (?) and the chest wall (increase / decrease) in size
Zero, increase
132
Laminar flow is present at (high / low) flow rates
Low
Parallel to the airway walls
133
Turbulence occurs at (higher or lower) flow rates
Higher
The flow is disorganized
134
Is the most important determinant of resistance
Radius of the tube
135
```
If the radius of a tube is reduced in half, the resistance will increase (?)-fold
A. 2
B. 4
C. 8
D. 16
```
D. 16
136
```
If length of the tube is increased 2-fold, the resistance will increase (?)-fold
A. 2
B. 4
C. 8
D. 16
```
A. 2
137
Resistance is (directly / inversely) proportional to the fourth power of the radius, and it is (directly / inversely) proportional to the length of the tube and to the viscosity of the gas
Inversely, directly
Berne and Levy Physiology p.436
138
```
In turbulent flow, gas movement occurs
A. Parallel to the axis of the tube
B. Perpendicular to the axis of the tube
C. Both a and b
D. None
```
C. Both parallel and perpendicular to the axis
139
Second major factor that determines rates of airflow in the airways
Airflow resistance
140
The major site of resistance along the bronchial tree
Large bronchi
141
T or F
| The smallest airway contribute very little to the overall resistance of the bronchial tree
T
142
Airflow velocity (increases / decreases) substantially as the effective effective cross-sectional area increases
Decreases
143
T or F
| Airway generations exist in series rather than in parallel
F, in parallel rather than in series
144
T or F
As airway diameter decreases, the resistance offered by each individual airway increases, but the large increase in parallel pathway reduces the resistance at each generation of branching
T
145
Airway resistance in healthy individuals is approximately
1 cm H2O/L sec
146
T or F
| Resistance to airflow decreases with increasing lung volume
T
147
Factors that increase airway resistance except
A. Mucus
B. Edema
C. Contraction of bronchial smooth muscle
D. Low density gas
D.
Gas density rises and results in an increase in airway resistance
148
A condition associated with increased airway resistance because of a combination of bronchospasm, airway inflammation and mucus
Status asthmaticus
