BLOOD Vessel & Hemodynamics Flashcards
(162 cards)
1
Q
Vessel walls structures
A
Know structures.
2
Q
Arteries
A
Carry blood away from the heart
3
Q
Atherosclerosis
A
Fats
4
Q
Elastic arteries
A
Conducting arteries.
5
Q
Exchange of oxygen
A
Capillaries.
6
Q
Capillary bed blood flow
A
Contolled by metarteriole/ Precapillary sphincters.
7
Q
Capillary bed blood flow
A
Controlled by metarteriole/ Pre-capillary sphincters.
8
Q
Types of capillaries: Continuous
A
Occurs in most tissues
9
Q
Types of capillaries:Fenestrated:
A
Kidneys small intestine, choroid plexus.
Cilliary bodies
10
Q
Types of capillaries: Sinusoids
A
Found in liver, bone marrow, and spleen
11
Q
Sinusoids
A
irregular filled blood spaces.
12
Q
Capillary exchanged (3)
A
Simple diffusion
Transcytosis
Bulk flow.
13
Q
Transcytosis
A
Large lipid insoluble molecules cross capillaries in vesicles via transcytosis
14
Q
Filtration is
A
pressure driven movement of fluid and solutes from blood capillaries into interstitial fluid.
15
Q
Filtration is promoted by
A
Blood hydrostatic pressure (BHP ) and Interstitial fluid osmotic pressure
16
Q
Reabsorption is
A
Pressure driven movement of fluid and solutes from interstitial fluid into blood capillaries
17
Q
Left over fluids
A
Goes over to lymph and then to SUBCLAVIAN SINUS
18
Q
Net filtration: 2 forces
A
Hydrostatic Pressure
Colloid Osmotic pressure.
19
Q
Increase capillary filtration
A
increase BP
Increased permeability
20
Q
Increase capillary filtration
A
increase BP permeability
Poor venous return
Increase histamine
kidney failure
21
Q
Decreased capillary reabsorption can be due to ________, ______, ______, ________, _____ there is low ______Pressure related to _______ ______
A
Hypoproteinemia, cirrhosis, burns, famine, kidney disease
Decrease oncotic pressure
Blood albumin
22
Q
Veins
A
lower pressure 10mmhg
Thinner wall, less muscular and elastic tissue
Expand easily, have high capacitance
23
Q
Venules two types:
A
Post capillary venules
Muscular venules
24
Q
Venous sinuses; what are they?
A
Veins within walls.
25
Blood flow
Volume of blood flowing through the tissue in a given time
26
Perfusion
Rate of blood flow per given mass of tissue
27
Important for delivery of nutrients and oxygen and removal
metabolic wastes
28
CO determinants
SV and HR
29
Co also can be determine
MAP / R
30
MAP
Measurements taken at intervals
31
BP
Force of blood exerts against vessel wall.
32
BP is determined by
CO
Blood volume
Vascular resistance.
33
Factors that affect or increased BP
Increases SV and HR
| Increase SBP
34
Regulation of BP and Flow
Local control
Neural
Hormonal Control -->
35
Metabolic Theory of autoregulation
Tissue inadequately perfused
| Wastes accumulate= Vasodilation
36
Atrial nutrieretic peptide
Increase sodium excretion == decreased BP
37
ADH comes from
Posterior Pituitary
Increased water retention
Vasoconstriction
BP increased
38
Epi and norepinelphrie
Catecholamines released from
39
Epi and norepinephrine
Catecholamines released from
40
Shock and homeostatis
Inadequate CO that results in failure of the CV system
41
Cell membranes dysfunction: what happens to metabolism?
cell metabolism is abnormal
42
Homeostatic responses to SHOCK
Activation of RAAS
Secretion of ADH
Activation fo SNS
43
Signs and Symptoms of shock
Homeostatic mechanisms bring about recovery
| Decreased BP tri
44
What is an an anastomose? Function?
| Arteries that do not form an anastomosis are called__________
Union of the branches of 2 or more arteries supplying the same region of the body
This provides an alternate route for blood flow
“end arteries”
45
Elastic arteries (“conducting” arteries)
Large diameter
More elastic fibers, less smooth muscle
Function as pressure reservoirs
46
Muscular arteries (“distributing” arteries)
Medium diameter
More smooth muscle, fewer elastic fibers
Distribute blood to various parts of the body
47
Elastic expansion and recoil of the aorta & its main branches Functions?
Maintaines steady flow of blood during diastole;
Decrease stress on small arteries
Smoothes out pressure fluctuations
48
Elastic aorta and arteries STRETCH During
Ventricular contraction
49
Elastic aorta and arteries RECOIL During
Ventricular Relaxation
50
In general a blood vessel has 3 layers:
```
Tunica interna (a.k.a. tunica intima)
Innermost layer, adjacent to lumen(AL)
```
```
Tunica media (SMEF)
Middle layer, smooth muscle and elastic fibers
```
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Tunica externa (around tissue)
Outermost layer, adjacent to surrounding tissue
```
51
Parts of the capillary? (outer to inner) BEL
Basement membrane
Endothelium
Lumen
52
Parts of the Veins (outer to inner) TSBLE
```
Tunica externa
Smooth Muscle (TUNICA MEDIA)
Basement membrane
Lumen
Endothelium
```
53
Parts of the ARTERIES (outer to inner)
| TETIBE
```
Tunica EXTERNA
External Elastic Lamina
Tunica Media (smooth muscle)
Internal elastic Lamina
Basement membrane
Endothelium (Tunica INTERNA)
```
54
The walls of the arteries are _______ which allows them to do what?
smooth muscle in the tunica media regulate________
elastic; which allows them to absorb the pressure created by ventricles of the heart (creating a pressure resevoir)
- diameter
55
What layer in the arteries regulate diameter
ELASTIC SMOOTH MUSCLE IN THE TUNICA MEDIA
56
BP ____ with age: arteries become _________
rises ; less distensible
57
Name 3 arterial sense organs
Carotid Bodies
Carotid Sinuses
Aortic Bodies
58
Carotid Sinuses : What do they cause?
| Sensitive to ?
Dilation in wall of internal carotid arteries. (sensitive to pressure change)
Monitor BP - signaling brainstem
HR decrease and vessels dilate.
59
FUNCTION: Carotid bodies : oval bodies near carotids (cluster of _______) monitor ________
adjust _______ to stabilize _________
oval bodies near carotids (cluster of chemoreceptors)
blood chemistry
respiratory rate to stabilize pH, CO2, and O2
60
Aortic bodies found were
| Function ?
walls of aorta
| same as carotid bodies
61
Arterial sense organ innervation 2 nerves
Vagus
| GLOSSOPHARYNGEAL
62
Aortic bodies innervated by (think VA)
Vagus nerve
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Carotid bodies innervated by (think GC)
Glossopharyngeal nerve
64
Capillaries are
microscopic vessels that connect arterioles and venules
65
Capillaries Walls composed of_________
| Thin walls permit _______ _________
single layer of cells and basement membrane
| he exchange of nutrients & wastes between blood and tissue
66
Capillary Bed BLOOD flow is controlled by what?
Metarteriole
| PreCapillary Sphincters
67
PreCapillary sphinters Relaxed, what happen?
Blood flow through the capillaries
68
PreCapillary sphinters CONTRACTED,What happens?
Blood flow through thorough fare channels.
69
Capillaries most common route ?
Heart --> Arteries--> Arterioles
| Capillaries --> Venules --> Veins
70
Portal system has
2 capillary beds.
71
Explain the PORTAL SYSTEM
Blood flows through two consecutive capillary networks before returning to heart
Hypothalamus/pituitary
Kidneys
Hepatic Portal System between intestines - liver
72
Arteriovenous shunt
artery flows directly into vein
73
Venous anastomosis
most common, blockage less serious
| alternate drainage of organsVenous anastomosis
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Which is the most common blockage?
Venous anastomosis.
75
Arterial anastomosis
collateral circulation (coronary)
76
****Continuous - occurs in most _____and Functions
occur in most tissues
| endothelial cells have tight junctions with intercellular clefts (allow passage of solutes)
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**** Fenestrated - KSCC
Function?
Filtration pores do what?
located in kidneys, small intestine, choroid plexus (CSF), ciliary bodies (aqueous humor)
1.organs that require rapid absorption or filtration
2.filtration pores – allows passage of small molecules
KSCC
78
****Sinusoids (LBS) – found in liver, bone marrow, spleen
| FUNCTIONS:
irregular blood-filled spaces; some have extra large fenestrations, allow proteins and blood cells to enter
79
Substances cross capillary walls by:
| DTB
Diffusion
Transcytosis
Bulk flow.
80
Capillaries exchange via DIFFUSION Include which substances?
COGAH
Substances such as oxygen, carbon dioxide, glucose, amino acids, and some hormones cross capillary walls via simple diffusion
81
Capillaries exchange via TRANSCYTOSIS INCLUDE (1) characteristics
Large, lipid-insoluble molecules (like insulin) cross capillary walls in vesicles via
82
Bulk flow is a passive process in which l
which large numbers of ions, molecules, or particles in a fluid move together in the same direction
Bulk flow is more important for regulation of the relative volumes of blood and interstitial fluid
83
Bulk flow occurs from an area of ______ _______ to an area of _______ ____, and it continues as long as a pressure difference exists
higher pressure ; lower pressure
84
Bulk flow is more important for ________
regulation of the relative volumes of blood and interstitial fluid
85
Define Filtration is
pressure-driven movement of fluid and solutes from blood capillaries into interstitial fluid
86
2 pressure promoting filtration
Blood Hydrostatic Pressure (BHP)
| Interstitial fluid osmotic pressure (IFOP)
87
Net filtration of arterial end at capillaries is _____L
20
88
Net REABSORPTION of Venous end at capillareis
17 L
89
Reabsorption is ___________
| Interstitial fluid hydrostatic pressure (IFHP) and blood colloid osmotic pressure (BCOP) promote reabsorption
pressure-driven movement of fluid and solutes from interstitial fluid into blood capillaries
90
2 pressure promoting REABSORPTION
Interstitial Fluid hydrostatic Pressure (IFHP)
| Blood Colloid Osmotic pressure (BCOP)
91
2 causes of Edema
```
Increased Capillary Filtration (increased BP or permeability )
Decreased Reabsorption ( Decreased oncotic pressure
```
92
Increased Capillary Filtration from
| PPICKI
poor venous return
congestive heart failure - pulmonary edema
insufficient muscular activity
kidney failure (water retention, hypertension)
Increased histamine = increased capillary permeability
93
Decreased Capillary Reabsorption from
| CFBK
```
hypoproteinemia (decreased oncotic pressure related to blood albumin)
cirrhosis
famine
burns
kidney disease
```
94
4 consequences of Edema
Tissue Necrosis: O2 delivery and waste removal impaired
Pulmonary Edema: suffocation
Cerebral Edema: Headaches, Nausea seizures coma
Circulatory Shock : xcessive fluid in tissue spaces cause low BP and blood voluem
95
What is Circulatory Shock?
excess fluid in tissue spaces causes low blood volume and low BP
96
Veins _____ blood pressure: _____mmHg with little fluctuation
______walls, ______ muscular and elastic tissue. expand ____,have_____capacitance valves aid _____ ______ ___ ________
lower; 10mmHg thinner ; less
easily, have high
skeletal muscles in upward blood flow
97
Venules postcapillary venules ____ _____than capillaries muscular venules have tunica _______
more porous ; tunica media
98
Venous sinuses
veins with thin walls, large lumens, no smooth muscle
99
Veins are formed from ____ ___
the union of several venules
100
Compared to arteries, veins have a ______tunica interna and media and a _______ tunica externa
thinner tunica interna and media and a thicker tunica externa
101
Veins have______elastic tissue and _____smooth muscle than arteries
less ; less
102
Veins have ____ ____ ____ that prevent backflow
one-way valves that
103
Venous return is the
the volume of blood flowing back to the heart through the systemic veins, occurs due to the pressure generated by contractions of the heart’s left ventricle
104
*****VENOURS RETURN (VEINS) ARE ASSISTED BY (CROGS)
```
Cardiac suction of expanding atrial space
Respiratory Pump
One way Valves
Gravity (for head and neck)
Skeletal muscle pump.
```
105
At rest the largest portion of the blood is where?
how much is in systemic arteries and arterioles
Heart
pulmonary
SYSTEMIC VEINS AND VENULES (BLOOD RESERVOIR (64%)
13%
7%
9%
106
****Perfusion definition
| Important for ____
rate of blood flow per given mass of tissue (ml/min/100g)
| delivery of nutrients and oxygen, and removal of metabolic wastes
107
*****Hemodynamics: Flow is based on ____and _____
Flow based on pressure and resistance
108
Total blood flow:
cardiac output (CO), the volume of blood that circulates through systemic (or pulmonary) circuits each minute
109
2 formulas for CO
```
CO= HR x SV
CO= MAP/ Resistance.
```
110
measurements taken at intervals of cardiac cycle, best estimate: diastolic pressure + (1/3 of pulse pressure)
diastolic pressure + (1/3 of pulse pressure)
111
Which varies with Gravity
MAP
112
Which varies with Gravity (hemodynamics)
MAP
113
– force blood exerts against vessel wall
Blood pressure.
114
AS the distance from the left ventricle increases, pressure
Decreases.
115
Contraction of the _______ generates BP
| The higher the BP, the greater the blood flow
ventricles
CO, blood volume, and vascular resistance
greater
116
3 BP determinants (CBV)
CO
Blood Volume
Vascular Resistance
117
R is the opposition to blood flow due to f
| The higher the R, the ______the blood flow
friction between blood and the walls of blood vessels
| smaller
118
Vascular Resistance depends on which 3 things (TBS)
Size of the blood vessel lumen
Blood viscosity
Total blood vessel length
119
3 ways of Regulation of BP and Flow
Autoregulation
Neural Regulation
Hormonal regulation.
120
Autoregulation of BP via
Physical and chemical stimuli
121
Autoregulation of BP via: Metabolic theory of autoregulation?
1. Tissue inadequately perfused
| 2. wastes accumulated resulting in VASODILATION
122
Autoregulation of BP via vasoactive chemicals:
substances that stimulate vasomotion; histamine, bradykinin
123
Autoregulation of BP via vasoactive :
| Reactive hyperemia
blood supply cut off then restored
124
Autoregulation of BP via vasoactive: Angiogenesis
growth of new vessels
regrowth of uterine lining, around obstructions, exercise, malignant tumors
controlled by growth factors and inhibitors
125
Neural CONTROL of BP and Blood flow
Medulla OBLONGATA VASOMOTOR CENTER
| sympathetic control stimulates most vessels to constrict, but dilates vessels in skeletal and cardiac muscle
126
In neural control of BP and BLOOD flow, SYMPATHETIC control stimulates most vessels to ______ but _____vessels in _____And cardiac muscle
Constrict; dilate ; skeletal
127
*****Medulla OBLONGATA VASOMOTOR CENTER integrates (BMC)
integrates 3 autonomic reflexes
Baroreflexes
Chemoreflexes
Medullary ischemic reflex
128
******BARORECEPTORS : Explain
```
Detect changes in BP detected by stretch receptors (baroreceptors), located in large arteries above heart aortic arch
aortic sinuses (behind aortic valve cusps)
carotid sinus (base of each internal carotid artery)
```
129
****Where are BARORECEPTORS LOCATED?
| ACA
large arteries above heart
aortic arch
aortic sinuses (behind aortic valve cusps)
carotid sinus (base of each internal carotid artery)
130
Signals sent to Medulla Oblongata:
1. Increase BP causes rate of signals to rise, inhibits vasomotor center, Decreases sympathetic tone, vasodilation causes BP decreased.
2. Decreasd BP causes rate of signals to drop, excites vasomotor center, increased sympathetic tone, vasoconstriction and BP increases
131
Chemoreceptors in aortic bodies and carotid bodies
located in aortic arch, external carotids, subclavian arteries
Autonomic response to changes in blood chemistry
pH, O2, CO2
primary role: adjust respiration
secondary role: vasomotor
hypoxemia, hypercapnia and acidosis stimulate chemoreceptors, stim. vasomotor center to cause vasoconstriction, inc. BP, inc. lung perfusion and gas exchange
132
Medullary Ischemic Reflex
| Inadequate perfusion of brainstem lead do
1. cardiac / vasomotor centers send sympathetic signals to heart & blood vessels
2. Increased C.O. and causes widespread vasoconstriction
increased BP
Other brain centers
stress, anger, arousal can also incr. BP
133
Input to CV centers comes from (nerve impulses)
higher Brain centers: cerebral cortex, limbic, hypothalamus
Proprioceptors: monitor joint movements
Baroreceptors: Monitor BP
Chemoreceptors: monitor Blood acidity, ph, CO2, H+
134
OUTPUT FROM CV to EFFECTOR organs
increased frequency of nerve impulses
Heart: decreased HR (parasympathetic vagus nerve)
heart: increased rate of contractility (through cardiac accelerator from sympathetic nerve)
Blood vessels: Vasoconstriction (through vasomotor nerves of sympathetic system
135
Hormonal control of BP
Renin --> Angiotensinogen -->Angiotensin I --> ACE --> Angiotensin II--> Vasoconstriction = increased BP
-->Aldosterone : stims. Kidney to reabsorb Na+, water follows salt = increased BP
136
BP rises with age because
Arteries become less distensible.
137
Walls of capillaries composed of
single layer of cells
| Basement membrane,
138
Simplest pathway
1 Capillary bed
139
Portal pathway
2 capillary beds.
140
Histamine makes capillaries more
permeable.
141
During inhalation
What happens to increased blood flow to what? Intrathoracic pressure, blood flow into thoracic veins, Diaphragm , intraabdomial pressure
```
Blood flow into thoracic veins.
Decreased
Increased
contracts
Increased.
```
142
During exhalation
What happens to increased blood flow to what? Intrathoracic pressure, blood flow into thoracic veins, Diaphragm , intraabdomial pressure
Increases blood flow to heart and abdominal veins
Increased thoracic pressure
Diaphragm relaxes
Decreased intra-abdominal pressure
Release of compression of abdominal veins.
143
Chemoreflex
Chemoreceptors in aortic bodies and carotid bodies. \
| Located in aortic arch, external carotids, subclavian arteries.
144
2 roles of chemoreflex
Autonomic response to change in blood chemistry
ph, O2, Co2
Primary role: Adjust respiration
Secondary role: Vasomotor
145
3 things that chemoreflex response to
hypoxemia
Hypercapnia
acidosis
stimulate vasomotor center to cause vasoconstriction by Increasing BP and lung perfusion and gas exchange.
146
Hormonal Control of BP --> 4 ways
ANP : increase sodium excretion = decrease BP
ADH: Increased water retention, vasocontriction = increase BP
Epinephrine and Norepinephrine: catecholamines released from adrenal medulla increase CO and BP
General somatic blood vessels: Binds to alpha adrenergic receptors , vasoconstriction = BP increased
147
Pulse points are
```
Superficial temporal artery
Facial artery
Common carotid artery
Brachial artery
Femoral artery
Popliteal
Radial
Dorsal artery of foot
```
148
Homeostatic Responses to Shock?
Activation of the Renin-angiotensin aldosterone system
Secretion of ADH
Activation of the sympathetic division
Release of local vasodilators.
149
Responses to hypovolemic shock
Increase Renin, ADH, Epi
150
Signs of SHOCK
Tachycardia
Clammy cool, pale skin
weak, rapid pulse
151
Shock is and
inadequate CO that results in failure of the CV systm to meet metabolic demands of body cells
Cell membranes dysfunction, cell metabolism is abnormal and cell death occurs
152
Types of SHOCK
Hypovolemic
Neurogenic (from decreased vasomotor tone)
Cardiogenic (acute MI)
Vascular (normal volume w/ vasodilation septic, anyphylactic)
Obstructive (PE, cardiac tamponade)
153
Compensated shock
Homeostatic mechanisms bring about recovery
Decreased BP triggers baroreflex and production of angiotensin II< both stimulate vasonconstriction.
If faint: Gravity restores blood flow to brain
154
Decompensated Shock
Life threatening positive feedback loops occur
Decreased CO--> Myocardial ischemia
slow circulation --> DIC --> slow circulation
Ischemia and acidosis _-> Decreased vasomotor tone, vasodilation, decreased CO, ischemia and acidosis of brainstem.
155
TIA
Lasts from a moment to a few hours
| WARNING OF IMPENDING STROKE
156
CVA
Brain infarction caused by ischemia
due to atherosclerois, thrombosis, ruptured aneurysm
recovery depends on surrounding neurons, collateral circulation
157
Ascending Aorta
Right and left coronary arteries supply heart
158
Aortic arch
Brachiocephalic
Right common carotid supplying right side of head
Right subclavian supplying R shoulder and upper limb
Left common carotid supplying left side of head
Left subclavian supplying shoulder and upper limb
159
Descending aorta include
Thoracic aorta above diaphragm
| Abdominal aorta below diaphragm.
160
Organs that require rapid absorption or filtration use what kind of capillaries
Fenestrated
161
Filtration pores does what?
Allow passage of small molecules.
162
characteristic of the sinusoids basement membrane
Sinusoids have an incomplete basement membrane
