Respiratory, Topnotch + CDB Flashcards
(157 cards)
1
Q
End of conducting zone
A
Terminal bronchioles
2
Q
How many generations of airways in the respiratory system
A
23
3
Q
How many alveoli are in the respiratory system
A
300 million
4
Q
Effect of SY nervous system on airways and via what receptor
A
Bronchodilation via b2
5
Q
Effect of PSY nervous system on airways and via what receptor
A
Bronchoconstriction via M
6
Q
% Type I pneumocyte in lungs
A
97%
7
Q
Histology of type I pneumocytes
A
Squamous
8
Q
Histology of type II pneumocytes
A
Cuboidal
9
Q
Purpose of Type I pneumocytes
A
Gas exchange
10
Q
Purpose of Type II pneumocytes (3)
A
1) Surfactant production
2) Turn into type I when needed
3) Proliferate during lung damage
11
Q
Special cells in the lungs in patients with CHF
A
Alveolar macrophages that have become siderophages/hemosiderin-laden macrophages
12
Q
Disease entity where goblet cells and submucous glands undergo hypertrophy and hyperplasia
A
COPD
13
Q
Cells that may play a role in epithelial regeneration, secrete component of surfactant, degrade toxins, and act as reserve cells
A
Clara cells
14
Q
Histology of Clara cells
A
Non-ciliated columnar
15
Q
Where pulmonary veins return
A
Left atrium
16
Q
Bronchial circulation receives ___% of cardiac output
A
1-2
17
Q
Where bronchial circulation drains (2)
A
1) 1/3 R atrium via bronchial veins
2) 2/3 L atrium via pulmonary veins
18
Q
Tidal volume in normal adult
A
500mL
19
Q
IRV
A
3000mL
20
Q
ERV
A
1200mL
21
Q
RV
A
1200mL
22
Q
Total volume of lung that does not participate in gas exchange
A
Physiologic dead space
23
Q
Formula of physiologic dead space
A
Anatomic dead space + alveolar dead space
24
Q
Air in conducting zone corresponds to
A
Anatomic dead space
25
Increase or decrease: Anatomic dead space during mechanical ventilation
Increase
26
Normal volume in conducting zone
150mL
27
Normal volume in alveolar dead space
0mL
28
Volume of air moved into and out of the lungs per unit time
Ventilation rate
29
Total rate of air movement in/out of lungs
Minute ventilation
30
Minute ventilation corrected for physiologic dead space
Alveolar ventilation
31
Formula for minute ventilation
Tidal volume x breaths per minutes
32
Formula for alveolar ventilation
(Tidal volume - Physiologic dead space) x breaths/min
33
Increased vs decreased: FEV1 and FVC in obstructive and restrictive lung diseases
Decreased
34
FEV1/FVC in normal healthy person
70%
35
FEV1/FVC ratio in restrictive disease
Increased or normal
36
FEV1/FVC ratio in obstructive disease
Decreased
37
Muscle involved in normal inspiration
Diaphragm
38
Muscle involved in normal expiration
None; passive process
39
Change in volume required for a fractional change of pulmonary pressure
Compliance
40
Pressure required for a fractional change of lung volume
Elastance
41
Pressure-volume work performed in moving air into and out of the lungs
Work of breathing
42
Property of matter that makes it resist deformation
Elastance
43
3 primary sources of resistance encountered during inspiration
1) Airway resistance
2) Compliance resistance
3) Tissue resistance
44
Airway resistance accounts for __% of work of breathing
20
45
Work that must be performed to overcome the intrinsic elastic recoil of the lungs
Compliance resistance/work
46
Compliance resistance accounts for __% of work of breathing
75
47
Law that implies that small changes in airway diameter have dramatic impact on airflow resistance because resistance is inversely related to the r^4
Poiseuille's Law
48
Large vs small airways: Arranged in series, resistance additive
Large
49
Large vs small airways: Arranged in parallel, resistance added reciprocally
Small
50
Forced Inspiration vs Expiration: External intercostals
Inspiration
51
Forced Inspiration vs Expiration: Internal intercostals
Expiration
52
FEV1
Maximum volume of air that can be exhaled in 1 second after maximal inspiration
53
Increased vs decreased: FRC in emphysema
Increased
54
Increased vs decreased: FRC in pulmonary fibrosis
Decreased
55
Force exerted by water in an air-fluid interface that minimizes surface area
Surface tension
56
Emphysema: Destruction of elastic tissue is mediated by
Neutrophil-derived elastases
57
Examples of restrictive lung disease (2)
1) Silicosis
| 2) Asbestosis
58
Increased tendency of alveoli to collapse on expiration as radius decreases
Law of Laplace
59
Predisposing factors for atelectasis in preterm babies
1) Small alveolar radius (50 um) compared to adult (100 um)
| 2) Lack of mature surfactant
60
Composition of surfactants
1) Lipids (90%)
| 2) Proteins (10%)
61
Active component of surfactant
DPPC
62
Mechanism for DPPC in reducing surface tension
Amphipathic nature
63
Start of surfactant production
24th week AOG
64
Maturation of surfactant
35th week AOG
65
L:S ratio that indicates lung maturation
>2.0
66
Transpulmonary pressure =
Alveolar pressure - Intrapleural pressure
67
Positive vs Negative: Transpulmonary pressure in expanded lungs
Positive
68
Positive vs Negative: Transpulmonary pressure in collapsed lungs
Negative
69
Ability of respiratory membrane to exchange gas
Diffusion capacity
70
Diffusion capacity of O2 at rest
21 mL/min/mmHg
71
Diffusion capacity of O2 at maximal exercise
65 mL/min/mmHg
72
Diffusion capacity for CO2 at rest
400-450 mL/min/mmHg
73
Diffusion capacity of CO2 at maximal exercise
1200-1300 mL/min/mmHg
74
Forms of gas in solutions
1) Dissolved
2) Bound
3) Chemically modified
75
Only form of gas that contributes to partial pressure
Dissolved gas
76
Difference between PAO2 and PaO2
A-a gradient
77
A vs a: Higher O2
Alveolar (A)
78
Why A is slightly higher than a
Due to blood that bypasses the alveoli (physiologic shunt)
79
2 types of alveolar-blood gas exchange
1) Perfusion-limited
| 2) Diffusion-limited
80
Characteristics of perfusion-limited gas exchange (2)
1) Gas equilibrates with the pulmonary capillary near the start of the pulmonary capillary
2) Diffusion increased only by increasing blood flow
81
Characteristic of diffusion-limited gas exchange
Gas does not equilibrate
82
O2 transport at rest
Perfusion-limited
83
O2 transport during exercise and disease states (emphysema, fibrosis)
Diffusion-limited
84
Percentage of dissolved O2
2%
85
Percentage of O2 bound to Hgb
98%
86
Hgb with iron in the ferric form hence does not bind with O2
Methemoglobin
87
Which hgb chain is abnormal in sickle cell anemia
Beta chain
88
Hgb increases the O2-carrying capacity of blood ___-fold
70
89
Shape of O2-Hgb dissociation curve
Sigmoidal
90
% saturated: PO2 of 25 mmHg
50% (P50)
91
% saturated: PO2 of 40 mmHg
75%
92
% saturated: PO2 of 100 mmHg
Almost 100%
93
Characteristic of O2-Hgb dissociation curve where binding of first O2 molecule increases affinity for 2nd O2 molecule and so forth
Positive cooperativity
94
Causes of shift to the left in the O2-Hgb dissociation curve
1) CO
| 2) HbF
95
90% (CDB: 70%) CO2 in blood is in the form of
HCO3-
96
5% (CDB: 7%) CO2 in blood is in the form of
Dissolved CO2
97
3% (CDB: 23%) CO2 in blood is in the form of
CarbaminoHgb
98
Cl-HCO3 exchange in the RBC
Chloride shift using Band 3 protein
99
O2 affecting affinity of CO2/H to Hgb INVERSELY
Haldane effect
100
CO2/H affecting affinity of O2 to Hgb INVERSELY
Bohr effect
101
Phenomenon normally encountered after a meal wherein there is a temporary increase in pH
Alkaline tide
102
Substances that cause bronchoconstriction
Leukotrienes
103
Effect of hypoxia (low pAO2) on pulmonary arterioles
Vasoconstriction
104
Zone of the lung: Local alveolar capillary pressure is less than alveolar air pressure THROUGHOUT the cycle
Zone 1
105
Zone of the lung: Local alveolar capillary systolic pressure > alveolar air pressure during systole but less than that during diastole
Zone 2
106
Zone of the lung: Local alveolar capillary pressure > alveolar air pressure THROUGHOUT the cycle
Zone 3
107
Lung zone seen with severe hemorrhage and positive-pressure ventilation
Zone 1
108
Normal V/Q ratio
0.8
109
V/Q in ventilated area of the lungs with (-) perfusion
Infinity
110
Disease entity where V/Q = infinity
Pulmonary embolism
111
V/Q in lungs with perfusion but no ventilation
0
112
Disease entity where V/Q = 0
Shunt/airway obstruction
113
Conversion of CO2 to carbonic acid as it reacts with water is catalyzed by what enzyme
Carbonic anhydrase
114
Structure that is defective in congenital diaphragmatic hernia
Pleuroperitoneal membrane
115
Anterior diaphragmatic hernia
Morgagni
116
Posterior diaphragmatic hernia
Bochdaleck
117
Accessory inspiratory muscles (3)
1) SCM
2) Scaleni
3) Serratus anterior
118
Accessory expiratory muscles
1) Internal intercostals
| 2) Abdominal recti
119
Pleural pressure at the beginning of inspiration
-5 cm H2O
120
Pleural pressure at the end of inspiration
-7.5 cm H2O
121
Flail chest (2)
1) 2 or more contiguous ribs
| 2) 2 or more fracture points
122
Driving force for inspiration
Negative intrapleural pressure created by diaphragm and external intercostals
123
Driving force for expiration
1) Increase in intrapleural pressure
| 2) Alveolar recoil
124
Alveolar ventilation at rest
4L/min
125
Mechanisms of maintaining V/Q matching (2)
1) Hypoxia-induced vasoconstriction
| 2) Changes during exercise (recruitment and distention)
126
Blood that bypasses the lungs or for another reason does not participate in gas exchange
Shunt
127
Anatomic shunt of the respiratory system
Blood bypasses lungs
128
Examples of anatomic shunt of the respiratory system (2)
1) Fetal blood flow
| 2) Intracardiac shunting
129
Physiologic shunt of the respiratory system
Blood flows to unventilated portions of lungs
130
Examples of physiologic shunt of the respiratory system (3)
1) Bronchial circulation
2) Pneumonia
3) Pulmonary edema
131
Causes the arterial PO2 to decrease from 104 to 95mmHg
Bronchial circulation
132
Regulators of respiration (5)
1) Cerebral cortex
2) Midbrain and pons
3) Central and peripheral chemoreceptors
4) Mechanoreceptors
5) Respiratory muscles
133
Central controller of breathing that can override the autonomic brainstem centers
Cerebral cortex
134
Creates the basic respiratory rhythm
Medulla
135
Modifies the basic respiratory rhythm
Pons
136
Inspiratory center
DRG
137
Overdrive mechanism during exercise
VRG
138
Prolongs inspiratory phase > decreases RR
Apneustic
139
Limits time for inspiration > increases RR
Pneumotaxic phase
140
Central chemoreceptors for respiration are found in the
Ventral medulla
141
Regulators of respiration: Ventral medulla responds directly to
CSF H+
142
Regulators of respiration: Response of ventral medulla to acidosis
Increases RR
143
Where peripheral chemoreceptors of respiration are found
Carotid and aortic bodies
144
Peripheral chemoreceptors of respiration respond mainly to
PaO2
145
Response of peripheral chemoreceptors of respiration to decrease on PaO2
Increases RR
146
Mechanoreceptors of respiration
1) Lung stretch receptors
2) Joint and muscle receptors
3) Irritant receptors
4) J receptors
147
Stimulus to lung stretch receptors
Lung distension
148
Response of lung stretch receptors
Hering-Breuer reflex
149
Hering-Breuer reflex
Decreases RR by prolonging expiratory time
150
Regulators of respiration: Stimulus to joint and muscle receptors
Limb movement
151
Regulators of respiration: Response of joint and muscle receptors
Increases RR during exercise
152
Stimulus to irritant receptors of respiration
Noxious chemicals
153
Regulators of respiration: Response of irritant receptors (2)
1) Bronchoconstriction
| 2) Increases RR
154
Responsible for dyspnea in left-sided heart failure
J receptors
155
Stimulus to J receptors
Pulmonary capillary engorgement
156
Response of J receptors
Rapid shallow breathing
157
Only gas in inspired air found exclusively in dissolved form
Nitrogen
