Exam 2 Cardiac and Respiratory Flashcards
1
Q
What is the percentage of blood volume in the heart?
A
7-10%
2
Q
What is the percentage of blood volume in the arteries?
A
13%
3
Q
What is the percentage of blood volume in the arterioles/capillaries?
A
7%
4
Q
What is the percentage of blood volume in veins?
A
64%
5
Q
What is the percentage of blood volume in the pulmonary circulation?
A
9%
6
Q
If Blood Pressure is increased, what is the physiological response?
A
- Vasodilation of the arterioles
- Decreased heart rate and contractility
7
Q
If blood pressure is decreased, what is the physiological response?
A
- Vasoconstriction of the arterioles
- Increased heart rate and contractility
8
Q
Hematocrit of blood related to ____
A
viscosity
9
Q
There is an inverse relationship between cross sectional area and ___.
A
velocity
10
Q
According to Ohm’s Law, with a decrease in BP, what will happen?
A
There will be a decrease in CO, HR and Resistance
11
Q
According to Ohm’s Law, with an increase in BP, what will happen?
A
There will be an increase in CO, HR and Resistance
12
Q
Blood viscosity is mostly determined by ____.
A
The Hematocrit
13
Q
Hematocrit is the ratio of ____
A
red blood cells volume to the total blood volume
14
Q
The higher the hematocrit, ____
A
the greater the viscosity of the blood
15
Q
Viscosity of plasma is ____
A
about 1.8
16
Q
Viscosity of the whole blood may change from ___
A
3 to 5
17
Q
_____ is the most important factor affecting blood flow resistance.
A
Radius of the blood flow
18
Q
The length of blood vessels changes only during _____.
A
individual vasculature growth. Under normal physiological conditions length is constant.
19
Q
Laminar Flow
A
- smooth tubes
- low rates of flow
- greatest flow in the center of the tube
- close to zero near the vessel wall
- flow directly proportional to pressure (linear relationship)
- angle of flow is less than 25o
20
Q
Turbulent Flow
A
- rough tubes
- high velocity of flow
- flow through bends >25o, narrowing, and orifices
- resistance to flow is higher during turbulence
- flow - pressure relationship (nolinear relationship )
21
Q
Reynolds Number
A
indicates conditions when flow changes from laminar to turbulent
22
Q
Reynold’s Number is directly proportional to ____
A
fluid velocity, fluid density, and tube diameter
23
Q
Reynold’s Number is inversely proportional to ____
A
fluid viscosity
24
Q
Reynolds numbers less than 2000 flow is ___
A
laminar
25
Reynolds numbers 2000-3000 flow is \_\_\_\_\_
unstable (laminar/turbulent)
This is the most common flow in physiological areas of the body.
26
If Reynolds number is more than 3000, the flow is \_\_\_
turbulent
27
Turbulent flow in the body is a predisposing factor of \_\_\_\_
thrombus formation
| (due to increased platelet activation)
28
LaPlace's Law and Arterioles
Arterioles develop a smaller wall tension despite relatively high intravascular pressure
Thus, vasoconstriction of the arteriole involves less work, than of larger vessels.
29
With an aortic aneurysm, as the radius increases, \_\_\_\_
wall tension also increases
30
Pressure inside the aorta
100 mmHg
31
Radius inside the aorta
10-2 m
32
Tension inside the aorta =
1 (abstract unit)
33
Pressure inside the capillary
25 mmHg
34
Radius of the capillary
4 X 10-6 m
35
Tension in the capillary
1 X 10-4 (abstract units)
36
Venturi Effect
If liquid flows through a reduced area in a tube, the linear velocity of flow increases
37
Bernoulli Theorem
Pressure exerted by liquid upon the wall in a reduced area decreases
38
Compliance (capacitance) is related to \_\_\_
distensibility
39
Veins
Thin-walled vessels
Contain large volume of blood (2/3 of the circulating blood volume)
Venous pressure is very low (0-10 mmHg)
Venous valves provide unidirectional blood flow
40
Major Factors Affecting Vein Function
1. Right atrial pressure (Central venous pressure)
2. Respiratory pump
3. Skeletal muscle pump ("Venous pump")
4. Venous valves
5. Gravitational Effect Upon the Venous Pressure
41
Organization of Microcirculation
Artery .\> Arteriole \> Pre-capillaries \> Capillaries \> Post-capillaries \> Venule \> Vein
42
What are the three types of capillaries?
1. Continuous capillaries
2. Fenestrated capillaries
3. Sinusoid capillaries
43
Typical capillary size is \_\_\_
5 mm
44
What is a continuous capillary?
What can pass through it?
One that has a basement membrane & endothelial layer
Interceullar cleft
Water and electrolytes can pass through
\*TIGHT
45
What is a fenestrated capillary?
What can pass through it?
One that has fenestrations
Water, electrolytes and plasma proteins can pass through it
46
What is a sinusoid capillary?
What can pass through it?
One that has an incomplete basement membrane
Has intercellular gap
Water, electrolytes, plasma proteins and blood can pass through
\*LEAKY
47
Where are continuous capillaries found in the body?
skin
muscle
lung
CNS
48
Where are fenestrated capillaries found in the body?
exocrine glands
renal glomeruli
intestinal mucosa
49
Starling Law in Microcirculation
1. Capillary hydrostatic pressure (30 mmHg -----15 mmHg)
2. Plasma oncotic pressure ( 25 mmHg )
3. Interstitial fluid hydrostatic pressure ( -2 mmHg )
4. Interstitial fluid oncotic pressure ( 8 mmHg )
50
Respiratory system is the link between \_\_\_.
the circulatory system and the atmosphere
51
High metabolic rate requires \_\_\_\_.
a specialized organ with high surface area gas exchange
52
Respiratory system has a very large \_\_\_
surface area for gas diffusion
53
The respiratory system provides close physical contact for \_\_\_
efficient gas exchange
54
The respiratory system provides excretory route for \_\_\_\_
volatile substances
55
The rspiratory system is important in \_\_\_
metabolism
56
What is the immunological role in the respiratory system?
airborne antigens
57
Nasopharyngeal Zone
NASAL CAVITIES, PARANASAL SINUSES, PHARYNX, and LARYNX
- air is cleaned
- air temperature and humidity may be changed
58
Tracheobronchial Zone
**conducting zone**: - 5 generations
**respiratory zone**: 17- 23 generations
mucocilliary transport (1cm/min)
respiratory bronchiole (0.5 mm diameter ) have no outer cartilage
59
Alveolar Zone
ALVEOLI
surface area 60-90 m2
300 million/adult lung
100-300 μm in diameter
0.1 µm -1 µm wall (alveolar-capillary membrane)
60
Factors Affecting Alveolar Stability
1. **Pulmonary Surfactant** (which decreases surface tension)
2. **Alveolar Interdependence** (If one starts to collapse the other will remain stable)
3. **Residual Volume** (amount left at end of every breath- it’s what holds the alveoli open even during expiration)
61
Surfactant decreases \_\_\_
The ability of water molecules to interact with each other
62
Phospholipids reduce \_\_\_
surface tension of the alveoli
63
Alveolar Cells Type I
alveolar wall
64
Alveolar Cells Type II
produce surfactant
65
Pulmonary Surfactant Facts
Equalizes pressure within alveoli
Prevents collapse of bronchioles and alveoli
Without surfactant, small alveoli would collapse
Cartilage prevents upper airways from collapsing
Surfactant packed in lamellar bodies exported by exocytosis
66
Turbulence – mostly in the area of \_\_\_\_\_\_
branches and bifurcations
67
Laminar flow is found only \_\_\_\_
in the smallest airways
68
Turbulence has a significant effect in \_\_\_\_
airway resistance
69
There is the lowest pressure in which bronchiole?
the medium bronchiole
70
Mechanics of Breathing
1. Lateral expansion of the thoracic cage
2. Superior-inferior expansion of the thoracic cage
3. Elastic recoil is responsible for lung elasticity
71
Pneumothorax
A dangerous pathophysiological condition. Pressure in the pleural cavity equals atmospheric pressure.
72
Negative Pressure in the Pleural Cavity
Intrapleural Pressure
1. Negative pressure in the pleural cavity (-4 to -9 mmHg)
2. Occurs during prenatal development
3. Chest cavity grows more rapidly than the lungs
4. Creates a semi-vacuum within the space
5. Tends to pull lung towards chest wall à slightly expanded
73
Ventilation Work
Change in intrapleural pressure x Change in respiratory volume
74
Ventilation is the sum of:
- work against the elastic recoil of the lung tissue
- work against the resistance component of the airways
75
Slow inspirations and expiration
- resistance component is negligible
- elastic component accounts for the work
76
Rapid inspirations and expiration
- resistance component is more important
77
Dalton’s Law
PRESSURE IS PROPORTIONAL TO THE CONCENTRATION OF GAS MOLECULES
78
Henry’s Law
GAS DISSOLVES IN THE LIQUID IN PROPORTION TO PARTIAL PRESSURE AND SOLUBILITY
79
Arterial PO2 at sea level
O2 saturation
100 mmHg
96
80
Arterial PO2 at 5,000 feet
O2 saturation
80 mmHg
95
81
Arterial PO2 at 15,000ft
O2 saturation
50 mmHg
O2 Saturation: 85
82
Arterial PO2 at 30,000ft
O2 saturation
25 mmHg
Saturation: 50
83
What are lungs directly exposed to?
atmospheric pollutants
products of thermo-degradation
84
Process of lung injury seems to be \_\_\_\_.
rapid
85
A high concentration of nanoparticles = \_\_\_\_
rapid death
