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Circulatory System-Rodriguez' Notes
Circulatory System-Rodriguez' Notes
111
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Not Applicable
06/16/2011

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Term
2 Systems of the circulatory system: High pressure, high energy ________ reservoir
Definition
arterial
Term
2 Systems of the circulatory system: A _________ pool of low pressure energy
Definition
venous
Term
The two systems of the circulatory system are connected by the ________
Definition
microcirculation
Term
Consisting of arterioles, capillaries, & venules
Definition
microcirculation
Term
Arteries progressively decrease in size from Aorta (largest) to the smallest called the _______. These are considered resistance vessels because they are dynamic [help regulate blood flow by contracting (vasoconstriction) & relaxing (vasodilation)]
Definition
Arterioles
Term
Arterioles measure ____ microns in diameter & cannot see!!
Definition
30
Term
Increased state of contraction
Definition
Vasoconstriction
Term
Decreased state of contraction (This mechanism is most important for the arterial side of the circuit)
Definition
Vasodilation
Term
Multi-branched elastic conduit set into oscillation by each beat of the heart
Definition
Arterial system
Term
Arterial system: Each beat pumps about ______ milliliters of blood into the aorta causing a blood pressure pulse (about 1/3rd of a cup)
Definition
70
Term
Cardiac Contraction Begins: 1. Pressure elevates in the _____ ventricle rises rapidly
Definition
Left
Term
Cardiac Contraction Begins: 2. Pressure of the left ventricle exceeds that of the _________
Definition
Aorta
Term
Cardiac Contraction Begins: 3. ________ opens, blood is ejected, BP rises
Definition
Aortic valve
Term
Tachycardia/Increased heart rate= ________ blood volume
Definition
increased
Term
Patient's cardiac status does/does not play an important role in the movement of blood throughout the vascular system
Definition
DOES
Term
Pressure changes determine __________ and direction of blood flow through the heart
Definition
valve action
Term
Period of cardiac cycle either when ventricles or atria are contracting
Definition
systole
Term
Resting phase of atria and ventricles
Definition
Diastole
Term
Heart valves open & close in response to differences in _____________ on their two sides.
Definition
blood pressure
Term
Do both atria contract at the same time?
Definition
Yes
Term
Do both Ventricles contract at the same time?
Definition
Yes
Term
Every time the heart beats pressure (potential) energy is generated and moves the blood!! Producing an arterial pressure wave that, travels rapidly throughout the _________ system, demonstrating a gradual transformation as it travels distally
Definition
arterial
Term
The pumping action of the heart results in _______ volume of blood in arteries to maintain a ______ pressure gradient between the arteries & veins
Definition
high; high
Term
Pressure is greater at the ________, gradually decreasing as the blood moves farther ______; This is necessary to maintain blood flow
Definition
heart; away
Term
The amount of blood that enters the arteries
Definition
Cardiac Output
Term
The amount of blood that leaves depends on the arterial pressure and on the total _____________ [which is controlled in turn by the amount of vasoconstriction in the arterioles (microcirculation)]
Definition
peripheral resistance
Term
If an artery directly feeds an organ the microcirculation is vasodilated or vasoconstricted?
Definition
Vasodilated
Term
If the microcirculation is feeding a muscle that is currently not working will it be vasoconstricted or vasodilated?
Definition
Vasoconstricted
Term
Each cardiac contraction _____the arteries
Definition
distends
Term
During this instant in time (cardiac contraction), the arteries serve as _________ to store some of the blood volume and potential energy supplied to the system
Definition
reservoirs
Term
Circulation of blood in the vascular system utilizes the basic principles of _________
Definition
fluid dynamics
Term
What determines whether blood flow exists in a vessel?
Definition
Energy gradient
Term
A difference in energy of the fluid at 2 locations
Definition
Energy gradient
Term
The greater the energy gradient the ______ the volume flow
Definition
greater
Term
On side of tube 70 mmHg, the other side 50mmHg...will flow exist?
Definition
Yes...towards the side with 50mmHg
Term
2 vessels...Vessel A=100mmHg & 80mmHg...Vessel B=100mmHg & 20mmHg....which will have greater volume of flow?
Definition
Vessel B (the difference is greater)
Term
Amount of blood that moves through a vessel in a time period; Units of volume divided by time (7 Liters per minute)
Definition
Volume flow
Term
Measure of swiftness or speed of blood flowing through through the circulation; Has direction; Units of distance divided by time (100 cm per second)
Definition
Velocity
Term
Do the following have the same velocity? Vessel A 1000 RBC's at 100cm/sec...Vessel B 5000 RBC's at 100 cm/sec.
Definition
Yes
Term
Do the following have the same volume flow? Vessel A 1000 RBC's at 100cm/sec...Vessel B 5000 RBC's at 100 cm/sec.
Definition
No (B has 5 times the flow)
Term
T/F? Direction of flow is from higher energy level to lower energy level.
Definition
T
Term
Vessel on the right side 50mmHg...on the left 70mmHg...what is direction of flow?
Definition
Right to Left (high to low)
Term
The total energy contained in moving fluid is the sum of pressure (potential), kinetic, and gravitational (if standing) energies (This is the proper to use NOT Pressure gradient)
Definition
Energy gradient
Term
Typically the difference in energy levels are due to ________ level difference
Definition
pressure
Term
Main form of energy present in flowing blood; distends the vessels; form of potential energy; created by the pumping action of the heart
Definition
Pressure energy (Potential)
Term
Ability of flowing blood to do work as a result of its velocity (blood is moving); A small component of the energy in blood when compared to potential energy; In normal circumstances: Equivalent to a few mmHg's
Definition
Kinetic energy
Term
Proportional to the blood's density (stable); squared to the velocity of blood (therefore, significant increases of this energy occur when flow is high Ex: Exercise, stenotic lesions with an increase in blood velocity); Converted back to pressure (potential) energy when velocity has normalized/decreased (Ex: Normal segment of the artery distal to a stenosis)
Definition
Kinetic energy
Term
______=velocity squared
Definition
Kinetic energy
Term
Due to the gravitional pull; Variations in the energy of blood is associated with differences in the levels of the body parts
Definition
Gravitational Energy
Term
The weight of a column of blood; Equals the weight of blood pressing on the vessels from heart level to the point of measurement (standing); Transmural pressure and distension of the vessels increases
Definition
Hydrostatic pressure
Term
Could arterial blood flow be improved by standing or laying down? Due to which pressure?
Definition
Standing; Hydrostatic
Term
How can venous distention due to standing be relieved?
Definition
Movement (The muscles push the blood upwards)
Term
What patient position can eliminate hydrostatic pressure?
Definition
Supine
Term
Low peripheral resistance=_____Flow rate
Definition
High
Term
High peripheral resistance=_______Flow rate
Definition
Low
Term
Flow that is continuous and 'steady' throughout systole & diastole
Definition
Low resistance
Term
Flow that ALWAYS moves forward
Definition
Low resistance
Term
Feeding a dilated vascular bed or organ
Definition
Low resistance
Term
Active arms/legs, ICA, Vertebral, Renal, Celiac, Splenic, Hepatic [Post-prandial (after you eat) SMA]
Definition
Low resistance
Term
Pulsatile in nature
Definition
High resistance
Term
Flow reversals are produced from the peripheral resistance
Definition
High resistance
Term
A normal high resistance flow pattern is called tri-phasic flow
Definition
High resistance
Term
Forward, reversal, & resumption of forward flow
Definition
High resistance
Term
Example: Resting arms/legs, ECA, subclavian, Aorta, Iliac arteries, extremity arteries, & fasting (pre-prandial) SMA
Definition
High resistance
Term
Diastolic flow reversal is a trademark of vessels that supply _________ peripheral vascular beds
Definition
High resistance
Term
Low resistance flow, broad systolic peak, sharp upstroke, delayed downstroke, High (velocity) diastolic component
Definition
Low
Term
Narrow and sharp systolic peak, Sharp upstroke, sharp downstroke, low diastolic component, High resistance flow
Definition
Moderate
Term
High resistance flow, narrow systolic peak, sharp upstroke, sharp downstroke, reversal component in early diastole
Definition
High pulsatility
Term
Exercise & peripheral arteries: Includes peripheral vasodilation in the microcirculation; thus _________ peripheral resistance; _________ blood flow (______ times more)
Definition
decreasing; increasing; 5-7
Term
Flow reversal __________ with vasoconstriction (cooling/resting)
Definition
increases
Term
If a waveform has resistance or is triphasic what type of resistance is it?
Definition
High resistance
Term
Flow reversal ________ with vasodilation (heating/activity)
Definition
decreases
Term
Peripheral resistance can also be ________ in response to heat, cold, tobacco and emotional distress.
Definition
altered
Term
Vasoconstriction and vasodilation of the blood vessels within the skeletal muscles are also influenced by _______________ that function primarily to regulate body temperature
Definition
sympathetic innervation fibers
Term
Tobacco ________________ the microcirculation
Definition
Vasoconstricts
Term
Characterized by individual layers of blood that travel at individual speeds; these layers of blood are parallel to each other & are aligned; layers at the wall are at "zero" speed; this type of flow pattern is associated with normal physiologic states
Definition
Laminar flow
Term
2 Types: Plug Flow & Parabolic Flow
Definition
Laminar Flow
Term
A) Occurs when all layers of the blood travel at the same velocity (typically seen at vessel origins) EX: Renal Artery near Aorta
Definition
Plug Flow (Type of laminar flow)
Term
B) Occurs when velocity is higher in the center of the lumen and slower at the periphery (bullet shaped profile) (typically seen downstream) EX: Renal Artery farther from Aorta
Definition
Parabolic Flow (Type of laminar flow)
Term
Are plug or parabolic flow normal?
Definition
Both!
Term
Energy is lost in the blood: due to friction between the lamina and particles, causing a decrease in pressure and energy levels from both systems
Definition
Viscous energy loss
Term
Energy is lost due to friction; Amount of friction & energy loss is determined MOSTLY by ______________
Definition
the dimensions of the vessels
Term
Small vessels: Microcirculation-Friction is increased due to the lamina rubbing against the walls resulting in resistance to flow (_________ energy loss)
Definition
increased
Term
Large Vessels: Less rubbing of layers against the walls of the vessel resulting in frictional energy losses at a minimal (resistance is at a __________)
Definition
minimum
Term
Occurs due to deviations from laminar flow due to: 1.Changes in direction of flow; 2.Changes in velocity
Definition
Inertial energy losses
Term
What are these types of deviation of laminar flow: bifurcations & curves (p145 figure 7-4-carotid bifurcation)?
Definition
Changes in Direction
Term
What are these types of deviation of laminar flow: parabolic flow profile becomes flattened; flow moves in a disorganized fashion; largest energy loss occurs at the EXIT of a stenosis?
Definition
Changes in Velocity
Term
Factors that affect resistance to flow: Movement of fluid is dependent upon the physical properties of the ______ & what is moving through.
Definition
fluid
Term
Viscosity and length have an effect on resistance, however, a change in _____________ has a more profound effect on resistance! (L, n are typically constant)
Definition
vessel diameter
Term
The _____ the vessel, the longer the fluid is contact with the vessel, thus increasing friction, producing energy losses, increasing resistance!
Definition
longer
Term
Friction is also generated by the viscous properties of fluid; the _______ the fluid, the greater molecular attraction and the more energy required to move the fluid, increased energy losses and increase of resistance
Definition
thicker
Term
High viscosity situation in the circulatory system: elevated hematocrit-erythrocytosis, polycythemia (___________ resistance)
Definition
increased
Term
Low viscosity situation in the circulatory system-low hematocrit-anemia (___________ resistance)
Definition
decreased
Term
If friction goes up resistance goes _____
Definition
up
Term
Resistance _______ with high viscous properties & longer vessels
Definition
increases
Term
Viscosity goes up velocity goes ______ (Inversely related)
Definition
down (It is not enough to significantly alter our studies sonographically)
Term
Calculates how much fluid is moving through a vessel
Definition
Poiseuille's Law
Term
Volume Flow is ______ proportional to the difference between the inflow & outflow pressures
Definition
directly
Term
Volume flow is _____ proportional to the fourth power of the radius
Definition
directly
Term
Volume flow is ______ proportional to the length of the tube and viscosity
Definition
inversely
Term
Helps define the relationship between: pressure, volume flow, & resistance
Definition
Poiseuille's Law
Term
Resistance is inversely related to r4, therefore, when there is a narrowing, resistance will ________!
Definition
Increase
Term
Pressure difference & blood flow can be measured, therefore _________ can be calculated
Definition
resistance
Term
Therefore, Poiseuille's law can be rewritten or simplified: Q=P/R (__________=Pressure/Resistance)
Definition
Volume Flow
Term
Movement of fluid through a tube and the movement of electricity through a wire are somewhat similar; Please be aware of the similar relationship between _________ and the way movement of fluid is described
Definition
Ohm's Law
Term
Poiseuille's Law can ONLY be used with __________ flow!
Definition
Laminar
Term
Realistically, alterations in blood flow occur MAINLY as a result of changes in the ________ of the vessels and the pressure energy available for flow. Vessel length & viscosity are pretty much stable!
Definition
radius
Term
Velocity is _______ related to cross-sectional area
Definition
Inversely
Term
In a closed system, Q (volume flow) is ______. v (velocity) is inversely proportional to A (area) (Ex: Area reduction from a stenosis)
Definition
constant
Term
Area goes down then velocity goes _____
Definition
up
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