Lung Function Flashcards
1
Q
the epithelial lining of the bronchi contain
A
single celled exocrine glands = goblet and cilliated cells
2
Q
primary gas exchange site
A
Alveoli
3
Q
the Pores of Kohn permit
A
collateral ventilation = permit air to pass thru the septa from alveolus to alveolus
4
Q
Type I alveolar cells
A
provide structure and support
5
Q
Type II alveolar cells
A
produce surfactant
6
Q
how does surfactant prevent lung collapse
A
reduces surface tension so that alveoli can expand
7
Q
why is surfactant important
A
reduces surface tension
controls lung inflammation
bacteriostatic
8
Q
alveolar macrophages
A
clear surfactant
ingest foreign material
move thru lymphatic system
9
Q
the acinus contains
A
alveolar ducts
10
Q
what are the processes of gas exchange in the body
A
ventilation
diffusion
perfusion
11
Q
what process of gas exchange is driven by the CV system
A
perfusion
12
Q
the upper airways are lined with
A
cilliated mucosa
13
Q
cilliated mucosa
A
warms and humidifies air
removes foreign particles
14
Q
the larynx
A
connects upper and lower airways
15
Q
the conducting airways are made up of
A
the nasopharynx and the oropharynx
16
Q
where do most airway obstructions happen
A
the right bronchi because it is anatomically larger and more vertical than the left bronchi
17
Q
pulmonary circulation functions
A
facilitates gas exchange
delivers nutrients to lung tissues
acts as a blood reservoir for the Lft Ventricle
serves as filtering system for circulation
18
Q
Pressure of the Pulmonary Circulation
A
18 mmHg
19
Q
Pressure of Systemic Circulation
A
90 mmHg
20
Q
only ________of the pulmonary vessels are filled with blood at any given time
A
1/3
21
Q
pulmonary artery enters the lung at
A
the hilum
22
Q
respiratory membrane (alveolocapillary membrane) is made up of these structures
A
epithelial basement membrane of the alveolar cell and the capillary basement membrane of the capillary endothelium
23
Q
3 types of alveolar cells
A
TYPE I = squamous alveolar cell
TYPE II = surfactant secreting cell
TYPE III = alveolar macrophage
24
Q
Path of Deoxygenated Blood thru heart
A
Systemic capillaries Blood loses O2 and gains CO2 => SVC, IVC, Coronary Sinus => Right Atrium => Tricuspid Valve =>Right Ventricle => Pulmonary Valve => Pulmonary Trunk and Pulmonary Arteries => Pulmonary Capillaries blood loses CO2 and gains O2
25
Path of Oxygenated Blood thru heart
Pulmonary Capillaries blood loses CO2 and gains O2 => Pulmonary Veins => Left Atrium => Bicuspid valve => Left Ventricle => Aortic valve => Aorta and sytemic arteries
26
Pulmonary Vein leaves at _______ and enter heart at_____
hila, left atrium
27
T/F Bronchial Circulation participates in Gas Exchange
True - it is part of systemic circulation and accounts for 1% of CO
28
Bronchial Arteries supply
trachea, bronchi and branches, esophagus, visceral pleura, vaso vasorum of thoracic aorta, pulmonary arteries and nerves, pulmonary veins, thoracic lymph nodes
29
T/F All bronchial capillaries drain into their own system
F; some go into Pulmonary veins and some contribute to normal R to L shunt
30
where does lymph fluid and alveolar macrophages enter the pulmonary lymph?
migrate from alveoli to the terminal bronchioles, impt process in immune defense and keeping lungs free of fluid
31
what's the most important cause of PA constriction?
low Alveolar partial pressure (PaO2)
32
pulmonary circulation is innervated by
the medulla and pons of the autonomic nervous system
33
humoral factors are
endocrine and immune messengers transported by the blood
34
contraction and relaxation of the pulmonary artery is controlled primarily by
humoral factors
35
hypoxia leads to
ATP production decrease, causing damage to mitochondria releasing intracellular Ca causing a cascade of enzymes that results in cell damage
36
alveolar and venous hypoxia causes
pulmonary artery constriction, reduction of the PA caliber
37
PA vasoconstriction can affect
one segment of the lung or the entire lung
38
Pulmonary Hypertension is ____________occurs when___________ occurs through out the vasculature of the lung
elevated pulmonary artery pressure, vasoconstriction
39
pulmonary vasoconstriction reflex occurs as a response to ___________so that _____________can match__________
hypoxia, ventilation, perfusion
40
pulmonary artery HTN can lead to
right heart failure
41
pulmonary system
1. ventilates alveoli
2. diffuses gases into/out of blood
3. perfuses the lungs so that the organs and the tissues of the body receive oxygnated blood
42
central chemoreceptors monitor
CSF by sensing pH, PaCO2, and PaO2
43
alveolar ventilation is not good if
PaCO2 increases
44
if CO2 increase pH_________________
increases
45
increase ventilation causes PaCO2 to
decrease
46
peripheral chemoreceptors are located in the
aortic bodies, aortic arch, and carotid bodies at bifurcation of carotids
47
3 types of lung sensory receptors
Irritant receptors, Stretch Receptors, and Pulmonary C-Fiber Recptors
48
stretch receptors are located at
smooth muscles of airways
49
irritant receptors are found at
epithelium of conducting airways
50
Hering-Breuer Expiratory Reflex
active in newborns or in adults on respirators and assist in ventilation, sensitive to high increase in Tidal Volumes and decrease ventilation rate and volume to protect against excess lung inflation
51
Pulmonary C-fiber receptors are also known as __________ and are located near _____________
J-receptors/Juxtapulmonary capillary receptors, capillaries in the alveolar septa
52
when stimulated stretch receptors
decrease ventilatory rate and volume
53
when stimulated irritant receptors
initiate cough reflex by causing bronchoconstriction and increase ventilation rate
54
J-receptors are sensitive to ___________pulmonary capillary pressure which when stimulated _________
increase- rapid, shallow breathing, laryngeal constriction on expiration, and mucus secretion, hypotension and bradycardia
55
T/F the adequacy of alveolar ventilation can be observed
F must be measured via arterial gas
56
CO2 is a product of ______________
cellular metabolism
57
T/F Ventilation and Respiration are the same
F Ventilation is the mechanical movement of air in and out of the lungs while Respiration is the exchange of O2 for CO2
58
medullary rythmicity area
in the brainstem its composed of interconnected bilateral groups of neuron = DRG & VRG
59
efferent fibers
carrying impulse from the CNS to the organs
60
afferent fibers
receive sensory information from the PNS and carry info to the brain (CNS)
61
VRG - Ventral Respiratory Group
is a cluster of efferent fibers sending impulses to the diaphragm and inspiratory intercostal muscles - responsible for the basic autorythmicity or respiration
62
DRG - Dorsal Respiratory Group
receives afferent impulses from peripheral chemoreceptors - alters breathing patterns to restore normal blood gases
63
pneumotaxic & apneustic centers
do not generate 1 respiratory rythm but modify inspiratory rate and depth
64
breathing can also be modified by
cortex, limbic system, hypothalamus, pattern of breathing due to emotion and disease
65
normal PaO2
80-100 mmHg
66
peripheral chemoreceptors monitor
pH (1),PaCO2,PaO2
67
peripheral chemoreceptors are primarily stimulated by
O2 levels in arterial blood
68
Receptors that are sensitive to noxious areosols
Irritant Receptors
69
Receptors located in the smooth muscle airways
Stretch Receptors
70
Receptors stimulated by increases in Volume
C-Fiber Receptors
71
Receptors sensitive to alterations in pulmonary capillary pressure
J-Receptors
72
diaphragm is innervated by
Phrenic Nerve (C3, C4, C5)
73
diaphragm contraction causes the muscle to flatten and
increase intrathoracic volume, and decrease intrathoracic pressure pulling air inwards
74
accessory muscles of inspiration
SCM and scalenes
75
accessory muscles of exhalation
none, usually passive
76
Law of Laplace
w/in a sphere surface tension makes expansion of the sphere difficult, because all force vectors point inward. the smaller the sphere the greater the pressure to inflate
77
Surfactant __________the Law of Laplace by
reverses, as the radius of the alveoli decreases because the surfactant concentration increase repellling the water molecules from ea other and reversely as the radius of the alveoli increases the surface tension increases due to decreasing surfactant molecules
78
function of surfactant
keeps alveoli open, free of fluid and pathogen
79
surfactant SP-B and SP-C
hydrophobic molecules seperating fluid molecules thereby decreasing surface tension
80
surfactant SP-A and SP-D
anti pathogenic
81
compliance
measure of lung and chest wall to swell as a result of pressure from inside
82
compliance is determined by
alveolar surface tension/elastic recoil of lung
83
lo compliance means ________work of inspiration or ______lungs
increased, stiff lungs
84
hi compliance means__________work of expiration or _______to inspire and lungs that________
increased, easy, have lost recoil
85
bronchoconstriction results in _________caused by__________
increased airway resistance, PS receptors in bronchial smooth muscles stimulated by irritants, or inflammatory mediators
86
bronchodilation results in ________caused by ______
decreased airway resistance, beta adrenergic receptor stimulation
87
airway resistance can also be increased by
edema of bronchial mucosa, airway obstruction
88
examples of airway obstruction
mucus, tumors, foreign bodies
89
more muscular effort required when
decreased lung compliance, chest wall compliance, airway obstruction
90
effective gas exchange requires
ventilation and perfusion to be equal
91
T/F Effective lung perfusion is body position dependent
T/ base of lung perfused better than apexes
92
Zone 1 (apex)
alveolar pressure exceeds pulmonary arterial and venous pressures
93
Zone 2 (above L Atrium)
alveolar pressure is greater than venous pressure but not greater than arterial pressure
94
Zone 3 (base of lung)
arterial and venous pressures are greater than alveolar pressure and blood flow is not affected by alveolar pressure
95
an ABG measure how much __________where a PulseOx measures ____________
how much PaO2, % Hgb bound to O2
96
in the lungs shifts to the right in the dissociation curve of Hgb corresponds to
the ease with which oxyhemoglobin dissociates and O2 moves from the capillaries into the cells of tissues
97
in the lungs shifts to the left in the dissociation curve of Hgb corresponds to
when PaO2 increases and HgB has a higher want for O2 than the tissues promoting association in the lungs and inhibits dissociation into the tissues
98
things that increase Hgb affinity to O2
hi pH, low lactic acid, hypothermic, lo DPG SHIFT to THE LEFT
99
things that decrease Hgb affinity for O2
decreased pH, hi PaCO2, hi lactic acid, increased temperature, hi DPG SHIFT To THE RIGHT
100
how is CO2 carried in blood
dissolved in plasma, H2CO3, carbamino compounds
101
the most important factor controlling the rate and depth of breathing is
the effect of CO2 on the central chemoreceptors
102
an increase in PCO2 in the blood leads to an increase in
H ions in the CSF/blood decreasing pH
103
what changes will occur if a person hyperventilates
during hyperventilation, CO2 is exhaled lowering PCO2
