Physiology Flashcards
1
Q
Cardio pulmonary physical therapy (CPPT) assesses what?
A
the functioning of a multi-system process effecting the human body
2
Q
The purpose of CPPT?
A
prevent, mitigate or reverse CP dysfunction
3
Q
Any insult to the O2 transport system will cause what
A
impairments, especially to exercise tolerance
4
Q
how is the CP system related to movement?
A
we need to breath and oxygen to move
5
Q
what will abnormalities of the cardiovascular and pulmonary system produce?
A
limitations in physical function
6
Q
movement must be supported by what systems?
A
musculoskeletal, neuromuscular and cardiopulmonary
7
Q
If you cannot breath, you can’t do what?
A
Move
8
Q
The first step in O2 transport system
A
VE
9
Q
What is VE
A
movement of air in and out of lungs in 1 min
10
Q
VE occurs as a result of what?
A
respiratory muscle activity
11
Q
what is the percent of the concentration of inspired O2
A
relatively constant at 21%
12
Q
Step 2 of the O2 transport
A
Gas Exchange
13
Q
where does gas exchange occur?
A
between the alveoli and pulmonary capillary blood
14
Q
Blood must have sufficient transit time in the pulmonary capillary to allow what to happen?
A
time for diffusion of gases
15
Q
Approximately what is the time needed for CO2 to move into the alveoli and for O2 to move into capillary blood
A
0.25 s
16
Q
alveoli that are well ventilated must also be what?
A
well perfused
17
Q
step 3 in the O2 transport
A
oxygenated blood enters the left side of the heart
18
Q
What is diastole
A
when blood moves into the left ventricle
19
Q
During diastole, the myocardium is what?
A
relaxed and compliant
20
Q
A high degree of compliance is important for what?
A
to facilitate the movement of blood into the left ventricle
21
Q
When can compliance decrease ?
A
with myocardial ischemia and LVH
22
Q
With conditions of decreased compliance what symptoms may occur?
A
decreased Q, dyspnea
23
Q
Step 4 in the O2 transport
A
Q to active muscles and the skin
24
Q
the degree of vasodilation versus constriction is controlled by ? centrally and locally
A
Centrally: SNS and locally: cellular metabolites
25
as muscles become more active, there is an increase in the local concentration of what? (3) and causes what?
metabolites, CO2, H+
| causes vasodilation
26
An increase in temp cans facilitate what?
vasodilatation
27
Step 5 of the O2 transport
O2 carrying capacity of blood
28
Factors that alter the oxyhemoglobin dissociation curve will affect what?
O2 delivery to skeletal muscles
29
A shift to the left impairs what
the amount of O2 extracted by the muscle (carboxyhemoglobin)
30
A shift to the right facilities what?
the unloading of O2 from hemoglobin (acidosis and increased body temperature)
31
90% saturation of O2 is what?
a red flag, stop exercising, need oxygen at home
32
What is the normal % of saturation O2
98 99
33
100 % of saturation of O2 means?
all RBC. Anemia
34
step 6 of the O2 transport
Homeostasis of blood gases
35
What needs to be prevented to not produce changes in the VE?
large fluctuations in ABGs and pH
36
what systems illustrate as interdigitating gears, forming a single gas transport system that supports cellular respiration
musculoskeletal, respiratory, cardiovascular
37
what two systems are functionally integrated as a single gas transport system for the support of cellular respiration?
cardiovascular and respiratory
38
the four O2 transport pathway and its component steps?
1. the delivery of fully oxygenated blood to peripheral tissues
2. the cellular uptake of O2 from the blood
3. the utilization of O2 in the cells
4. the Return of partially desaturated blood to the lungs
39
Flow of air into the lungs is a result of what?
pressure differences between the lungs and atmosphere
40
during inspiration, alveolar press is what compared to the atm (- thoracic pressure)
less
41
muscular contraction of the respiratory muscles lowers what and enlarges what?
lowers alveolar pressure
| enlarges the thorax
42
pts. who cannot create negative pressure are what?
mechanically ventilated
43
when does exhalation occur?
alveolar pressure is greater than atm (+ thoracic pressure)
44
Compliance
ease with which the lungs are inflated during inspiration
45
how is distensibility measured
change in V / Change in P
46
What does an increase in P cause
a decrease in compliance and the alveolus will not inflate
47
A healthy lung resists what
enlargement during inspiration and tried to pull away from the chest wall
48
The normal lung is very what?
compliant
49
when does the lung become rigid
diseases that cause alveolar, interstitial, or pleural fibrosis and alveolar edema (decrease in compliance)
50
what increases compliance?
Emphysema and age
51
What is compliance dependent on?
surfactant
52
What is surfactant
a lipoprotein fluid that lines the alveoli
53
Restrictive
breathing in through a sip straw
54
Obstructive
blowing up a balloon
55
Surfactant increases compliance by
lowering the surface tension of the alveolus, reducing the muscular effort to ventilate the lungs
56
A decrease in surfactant causes the alveolus to
collapse as in respiratory distress syndrome of the infant and ARDS
57
Flow of air into the lungs depends on what
pressure differences and the resistance to flow by the A/w
58
Upper AW are responsible for what percent of RAW
45%
59
The Raw in the lower AW depends on what?
many factors and is difficult to predict
60
Flow through the lower AW can be either?
Laminar or turbulent
61
Laminar flow
Streamlined where resistance occurs between the sides of the tubes and the air molecules
62
Laminar flow occurs at what rates
low flow
63
When does Turbulent occur?
when there are frequent molecular collisions- high rates, irregularities
64
What can cause turbulent irregularities ?
mucus, exudate, tumor, other obstructions
65
A normal lung has turbulent or laminar
Mixture of both
66
The elastic properties of the lung tend to collapse the lung if there is no what?
counterbalanced by external forces
67
Elastic recoil of the lungs is pulling in what direction
inward
68
Elastic recoil of the lungs is balanced by what?
the elastic recoil of the chest wall
69
Elastic recoil of the chest wall is pulling in what direction
outward
70
if the elastic recoil forces are interrupted what occurs?
(pneumothorax) lung collapses and the thoracic wall expands
71
Explain the barrel chest of a pt with COPD
elastic tension of the chest wall being unopposed by the forces of the lungs.
72
which direction does the chest move with increased compliance and why
outwards, decrease in elastic recoil of the lungs
73
Which direction does the chest move with decrease compliance and why?
inward, increase in elastic recoil of the lungs
74
What is ventilation
process by which air moves in to the lungs
75
difference in ventilation throughout the lungs is due to the effect of what ?
POSITION or gravity on the lungs
76
Where is ventilation favored regardless of body position
lower most lung
77
Where must air cross (4)
- Alveolar-capillary membrane
- Surfactant lining
- Alveolar epithelial membrane
- Capillary endothelial membrane
78
O2 travels more then air, where else does it go, where does it stop?
- layer of plasma
- erythtocyte membrane
- intracellular fluid in erythrocyte
- end hemoglobin molecule
79
O2 molecule passes?
gas, tissue and liquid
80
Diffusion in a healthy lung
very quick
81
what separates the 2 membranes
fluid, edema, exudate
82
O2 or CO2 diffusion slower through membrane ?
O2
83
Patients with diffusion problems have
hypoxemia but normal PaCO2
84
diffusion disorders?
disorders of Connective tissue, (sarcoidosis, scleroderma, pulmonary edema)
85
What is perfusion?
Blood flow of the pulmonary circulation available for gas exchange
86
Pulmonary circulation operates at what type of pressure unlike the systematic circulation
low pressure
87
Walls in the pulmonary circulation are?
thinner
88
PAP should be?
10-20 mmHg
89
Hydrostatic pressure has a side effect on what?
lung perfusion, lower lobes
90
Hydrostatic pressure reflects the effect of what?
gravity on the blood
91
hydrostatic pressure favors perfusion on what portions of the lungs
lower lung/ dependent portions
92
Pull blood vessels contract in response to what?
low arterial pressures of O2
93
What is Hypoxic vasoconstriction ?
protective reflex diverting blood away from under ventilated or poorly oxygenated lung areas.
94
Hypoxic vasoconstriction leads to what?
pull hypertension
95
What causes Hypoxic vasoconstriction ?
a low pH
96
what 3 factors are dependent on the distribution of blood within the pulmonary circulation
1. gravity
2. amount of blood ejected by the right ventricle
3. pulmonary vascular resistance
97
Ventilation-perfusion ratio V/Q
Ventilated area of the lung need to be in contact with perfused areas of the lung to effect normal gas exchange
98
Where are the areas of optimal gas exchange occur?
where there is the greatest amount of perfusion and ventilation
99
what will change the V/Q ratio?
changes in position
100
What is the alveolar gas flow referred as?
alveolar ventilation (V)
101
What is the pulmonary capillary blood flow referred as?
pulmonary perfusion (Q)
102
How much V does the lungs receive
4 L/min
103
how much Q does the lungs receive
5 L/min
104
what section of the lung is optimal zone for ventilation and perfusion?
Middle/ zone II
105
Most dependent section of the lung
Lowest/ Zone III
106
What regions acts as a Shunt
low ratios/ perfusion in excess of vent
107
What regions acts as dead space?
high ratios/ vent in excess of perfusion
108
shunts
no vent but perfusion
109
dead space
no perfusion but vent
110
Test used to rule out pulmon embolism
V/Q scan
111
Do you treat someone who is getting a V/Q scan
No
112
Where is there increases in vent and perfusion?
down the upright lung
113
where do optimal V/Q ratios occur?
mid-lung zones
114
Why do uneven vents occur?
uneven RAW or uneven compliance in different parts of the lung
115
What are problems that have adverse effects on O2 transport? (6)
- respiratory muscle dysfunction and chest wall deformities
- V/Q mismatching
- Diffusion abnormalities
- Inadequate cardiac output
- Limitations in peripheral blood flow
- Low O2 carrying capacity
