Respiratory I Ventilation Flashcards
1
Q
what are the functions of the respiratory system
A
-exchange of gases between the atmosphere and the blood
- regulation of pH
- protection from inhaled pathogens and irritants
-vocalization
-route for water and heat loss
2
Q
what is ventilation
A
air moves in and out of lungs
3
Q
what do gases diffuse between
A
alveoli and blood
-blood and tissues
4
Q
what is the visceral pleura
A
attaches to the surface of the lung
5
Q
what is the parietal pleura
A
covers the surface of the chest wall, diaphragm, and mediastinum
6
Q
what does the pleural space contain
A
a thin layer of pleural fluid under negative pressure
7
Q
what is the negative pressure in the pleural space referred to as
A
the intrapleural pressure
8
Q
is intrapleural pressure higher or lower than atmospheric pressure
A
subatmospheric - lower
9
Q
what is a pleural effusion
A
excess fluid in the pleural space which makes lung expansion difficult so the person will breathe shallow and fast
10
Q
how many lobes are in the right and left lobe
A
right-3
left-2
11
Q
what zone is the best site for gas exchange and why
A
zone 3 because it gets more air and blood due to gravity
12
Q
what zone are the alveoli largest
A
zone 1
13
Q
normally most of the lungs are zones _____
A
3 and 2
14
Q
what two functional zones is the respiratory system divided into
A
conducting zone and the respiratory zone
15
Q
what does the conducting zone consist of
A
trachea, bronchi, bronchioles, and terminal bronchioles
16
Q
what does the respiratory zone consist of
A
respiratory bronchioles, alveolar ducts, and alveolar sacs
17
Q
how much air is in the conducting zone and what is it called
A
150 mL called the anatomic dead space
18
Q
what happens to the diameter and number of the airways as you move down
A
the diameter decreases and the number of each increases
19
Q
what happens to the amount of cartilage and smooth muscle of the airways as you move down
A
decrease in cartilage and increase in smooth muscle
20
Q
what happens to surface area of the airways as you move down
A
increases
21
Q
what happens to air in the conducting zone
A
it is warmed, humidified and filtered
22
Q
what is the function of cartilage and smooth muscle
A
cartilage: prevents airway collapse
smooth muscle: alters resistance to airflow
23
Q
what is the formula for velocity of air
A
V = flow/cross sectional area
24
Q
what are the cell types in alveoli
A
-type I cells (simple squamous epithelial cells)
- type II alveolar (produce surfactant)
-macrophages
25
what cells make up wall of alveoli
type I
26
what is the basement membrane fused of
the endothelium and the alveolar epithelium
27
what is the typical transit time at rest for an erythrocyte through an alveolar capillary
0.75 seconds
28
how long does gas exchange take
0.25 seconds
29
what are the numbers for diffusion equilibrium for O2 and CO2
PAO2 and PaO2 = 100
PACO2 and PaCO2 = 40
30
what are the partial pressure for O2 and CO2 in arteries
PaO2: 40 mmHg
PaCO2: 45 mmHg
31
what are the partial pressures for O2 and CO2 in alveoli
PAO2: 100mmHg
PACO2: 40 mmHg
32
what type of muscles are respiratory muscles
skeletal muscles
33
what controls the alpha motor neurons in the respiratory muscles
neurons in the medulla and pons
34
what are the inspiratory muscles and what does contraction do
-mainly diaphragm and external intercostals but also sternocleidomastoid and scalenes
- increases the size of the thorax and lungs and decreases Palv
35
what are the expiratory muscles and what does contraction do
-mostly internal intercostals, external oblique, internal oblique, transversus abdominus, and rectus abdominus
-contraction decreases the size of the thorax and the lungs causing increase in Palv
36
when do expiratory muscles contract
only with active expiration
37
what do the internal intercostals do in expiration
depress the ribs
38
what do the abdominal muscles do in expiration
push abdominal contents against the diaphragm compressing the lungs
39
what is the primary inspiratory muscle
the diaphragm
40
what is boyles law
P1V1=P2V2
41
what changes first: changes in volume or changes in pressure
changes in volume
42
for air to enter the lungs the pressure in the alveoli must be_____
lower than the atmospheric pressure
43
for air to leave the lungs the pressure in the alveoli must be ____
higher than atmospheric pressure
44
which way do the chest and lung recoil
chest recoils outward, lungs recoil inward
45
what does the elastic recoil of the lungs favor
a decrease in lung volume or compression
46
what does the elastic recoil of the chest wall favor
an increase in lung volume or expansion
47
how is the intrapleural fluid related to recoil
it overcomes recoil and keeps the chest wall and lungs attached together so when the chest moves the lungs move with it
48
what is the formula for transmural or transpulmonary pressure
Ptp = Palv - Pip
49
what must happen to the transmural pressure to produce inspiration vs expiration
-must increase to produce inspiration
-must decrease to produce expiration
50
what pressure value equals zero in a pneumothorax
Ptp is 0 because Pip = Patm
51
where is half of the energy expended for inspiration stored and when is it released
stored in elastic recoil and released during expiration to overcome airway resistance
52
at what pressure does inspiration begin
at rest when Patm = Palv
53
what happens to the pressures during inspiration
decrease in Pip from -5 to -7.5mmHg causes Ptp to increase to 7.5 mmHg which causes the lung volume to increase
54
what happens to Palv as air enters the lungs
it increases again
55
when does air flow stop in inspiration
when Palv = Patm again
56
what volume of air does normal inspiration move
500mL - tidal volume
57
why is expiration a passive process in relaxed breathing
relaxation of inspiratory muscles
58
what happens to the pressures during expiration
increase in Pip from -7.5 to -5 mmHg which causes Ptp to decrease from 7.5 to 5 mmHg
59
what 2 factors affect pulmonary ventilation
lung compliance and airway resistance
60
what is the formula for compliance
change in volume/ change in pressure
61
what does high compliance vs low compliance mean
high: lung stretches easily
low: difficult for lung to stretch
62
where are alveoli more compliant
in the base of the lungs
63
what is the opposite of compliance
elasticity
64
what is elasticity
lungs ability to return to its normal resting position
65
what does high elasticity mean
easy recoil
66
lungs with lower compliance require a ___ Ptp to increase volume
larger
67
what happens in obstructive lung disease and what happens to compliance
-elastic fibers destroyed
- increase in compliance: will breathe deep and slowly to reduce the work of breathing
68
what happens in restrictive lung disease to compliance
decreased compliance
-will breathe shallow and fast to reduce the work of breathing
69
what is an example of obstructive lung disease
emphysema
70
what is an example of restrictive lung disease
pulmonary fibrosis
71
how much of pulmonary elasticity does surface tension account for
two thirds
72
what is surface tension
force that occurs at any gas liquid interface due to the cohesive forces between liquid molecules
73
what force does the fluid covering alveoli exert
a constant force favoring contraction
74
what does the law of laplace describe
the relationship between surface tension and radius of an alveolus
75
what is the formula for the law of laplace
P = 2T/r
76
if two alveoli are connected and the surface tension is equal, in which of the alveoli is the pressure greater? because of this where will the air flow
pressure is greater in the small alveolus and air will flwo into the larger alveoli
77
what does surfactant do and what is it secreted by
reduces surface tension (and thus elasticity) and equalizes pressure between alveoli of different sizes
-secreted by type II alveolar cells
78
what is surfactant made of
phospholipids
79
some components of surfactant are components of ____ immunity
innate
80
surfactant is particularly important for reducing surface tension where and what does this do
in small alveoli which decreases the likelihood of alveolar collapse
81
surfactant decreases the work of ____
inspiration
82
when is surfactant production increased
with hyperinflation of the lungs, exercise and beta adrenergic agonists
83
what pathologies are associated with decreases in surfactant production
infant respiratory distress syndrome, acute respiratory distress syndrome, chronic smoking
84
what is the formula for air flow in the lungs
(Patm- Palv)/ resistance
85
what are the determinants of resistance
-radius of bronchi/bronchioles
-viscosity of substance
-length of tube
86
what determines the radius of bronchi/bronchioles
-bronchodilation
-bronchoconstriction
-mucus accumulation
87
what causes bronchodilation
EPI on B2, decreased O2and increased CO2
88
what causes bronchoconstriction
ACH on M3, increased O2, decreased CO2, and histamine
89
the airways with the smallest radius have the ____individual resistance and the ____ total resistance
highest individual and smallest total
90
what are the pathologies that increase airway resistance
obstructive diseases such as asthma, emphysema and bronchitis
91
what is the resting normal tidal volume
500mL
92
what is IRV
deepest breath possible
93
what is expiratory reserve volume
deepest breath out possible
94
what is the normal anatomic dead space
1 mL per pound of idea body weight which is the conducting zone of the respiratory system
95
what is the formula for the physiologic dead space
anatomic DS + alveolar DS
96
describe the alveolar dead space of a healthy young person
little or no alveolar dead space
97
describe the alveolar dead space of someone with low cardiac output and why
a lot of alveolar dead space due to low perfusion and thus a higher V/Q ratio
98
what is included in vital capacity
IRV + ERV + TV
99
what is included in total lung capacity
VC + RV
100
what is included in inspiratory capacity
TV + IRV
101
what is included in functional residual capacity
ERV + RV
102
what is the formula for minute, pulmonary or total ventilation
tidal volume x respiration rate
103
what is the formula for alveolar ventilation
(tidal volume - dead space volume) x respiration rate
104
which pulmonary function test is a better indicator of gas exchange: total ventilation or alveolar ventilation
alveolar ventilation
105
what is the normal respiratory rate
between 12-20 breaths/minute at rest
106
is it better to breath deeper or faster and why
deeper to get more air into the respiratory zone for gas exchange
107
what do measurements of expiratory flow reflect
air flow within large airways. used to test for increased airway resistance
108
what are the measurements of expiratory flow
-forced vital capacity
- forced expiration volume
109
what is the forced vital capacity
volume of air forcibly expired after maximal inhalation ~5L
110
what is the forced expiration volume
fraction of FVC expired during the first second
111
what is the normal forced expiration volume
.8 or 80%
112
what is FEV1 in obstructive lung diseases
less than 80%
113
what does FEV1 reflect
flow in large airways
114
what is eupnea
normal quiet breathing
115
what is hyperpnea and when does it occur
increased rate or volume due to higher metabolism
-during exercise
116
what is hyperventilation and when does it occur
increased rate or volume without increased metabolism
- during emotions,blowing up a ballon
117
what is hypoventilation and when does it occur
- decreased alveolar ventilation
- shallow breathing, asthma, restrictive lung disease
118
what is tachypnea and when does it occur
rapid breathing usually with decreased depth
-panting
119
what is dyspnea and when does it occur
-difficulty breathing, air hunger
- various pathologies or hard exercise
120
what percentage of total body energy does normal quiet breathing take
3-5%
121
what are obstructive diseases due to and examples
-due to increased airway resistance
- ex: asthma, emphysema, bronchitis, cystic fibrosis
122
what do obstructive diseases primarily impact and describe the breathing pattern
impacts expiration
- breathe slow and deep
123
what are restrictive diseases due to and example
decreased lung compliance
-ex: pulmonary fibrosis
124
what do restrictive diseases primarily impact and describe the breathing patttern
-impacts inspiration
-breathe fast and shallow
125
what is atopic asthma
-IgE mediated- type 1 hypersensitivity reaction
-an allergen leads to an inflammatory response that causes bronchospasms that obstruct airflow
126
what can chronic inflammation in atopic asthma lead to
imparied mucociliary response, edema and increased airway responsiveness
127
what are the quick relief and long term treatment options for atopic asthma
-quick: B2 agonists, anticholinergic agents
- long: inhaled corticosteroids, long acting bronchodilators
128
what can nonatopic asthma occur with
respiratory infections, exercise, hyperventilation, cold air, inhaled irritants, aspirin and other NSAIDS
129
what happens in the early phase response and late phase responses of atopic asthma
early: increased mucus production and mast cells release cytokines upon IgE binding
late: increased vascular permeability and edema
130
what type of lung disease is cystic fibrosis and what happens in it
- obstructive disease
-autosomal recessive disorder resulting in defective CTFR ion channel that results in abnormally thick mucus that obstructs airways
-defective Cl- secretion and excessive Na+ and H2O absorption
131
what are the treatments for cystic fibrosis
-antibiotics
-chest physical therapy (percussion and postural drainage)
- mucolytic agents
-pancreatic enzyme replacement
132
what chromosome is defective in cystic fibrosis
7
133
what is the pathway in cystic fibrosis
abnormal thick and viscid secretions
-development of a microenvironment that is protective of microbial agents and defective mucociliary clearance
- chronic airway obstruction and bacterial infection
- neutrophil influx and release of elastase and inflammatory mediators
- development of chronic bronchitis and respiratory failure
134
what happens in emphysema
destruction of elastic fibers and enlargement of airspaces due to destruction of airspace walls
135
what does emphysema lead to
- airway collapse which increases resistance and decreases flow
- damage to alveolar membrane so decreased gas exchange
- decreased elasticity and increased compliance
136
what happens in restrictive respiratory diseases
-chronic inflammation and the normal lung tissue is replaced with scar tissue/fibrosis (collagen fibers decrease lung compliance)
- low compliance - more difficult to inhale
- work of breathing increases (pt breathes shallow and fast decreases alveolar ventilation and decreases gas exchange
137
what are signs and symptoms of restrictive pulmonary diseases
-increased respiratory rate
-chronic cough - dry, non productive
-polycythemia due to hypoxia (decreased PaO2 and increased # RBCs)
