Venous Insufficiency
Hydrostatic Pressure
Principles/
Equations 1
Principles/
Equations 2
Miscellaneous
100
Because of the pressure volume relationship that exists within vessels, When there is low pressure in a vein the vessel changes to more of this kind of a shape.
What is Elliptical shape. Flatter. Ovoid.
100
The hydrostatic pressure at the heart when a person is standing upright
What is 0 (the right atrium is the reference point)
100
Using Poiseulle's Law, this is a descriptive effect of flow when radius is increased.
What is a large/dramatic increase in Flow. Thus residual radius rather than the percent stenosis affects blood flow.
100
This must occur when pressure inside a vessel decreases (Bernoulli)
What is Velocity is increased (stenosis) *Show them by sideways B trick*
100
This picture demonstrates this kind of peripheral resistance: http://img.medscape.com/fullsize/migrated/494/434/ar494434.fig2.jpg
What is low resistance
200
This is an example of the proper sequence order of flow when a person is not suffering from venous insufficiency (perforator, posterior tibial vein, greater saphenous vein)
What is starting at the PTV's (deep vein) extra blood flow from travels through a perforator vein (mode of transport) to the great saphenous vein (the helper vein).
200
When the height of an object is increased above the point of reference, the hydrostatic pressure does this
What is decrease (Think of sticking arm above head. "Taller" than rt atrium but hydrostatic pressure decreases).
200
This happens to velocity when flow stays the same but area increases?
What is decrease in velocity (V= Q/A)
200
These are two of the three factors that influence resistance in Pouseiulle's Law
What is vessel length, fluid viscosity, tube radius
200
These are 2 of the 3 major factors in resistance
What is length, fluid viscosity, and tube radius.
300
Primary varicose veins are caused by this __________. This regurgitation results in an increase in venous pressure and thus the volume _______
What are incompetent valves, volume increases (the veins are filled with blood and expand to a larger size)
300
The hydrostatic pressure of a person lying supine on an exam table is near this value at the level of the of their ear.
What is near zero (-2 to 15mmHg)
300
***DAILY DOUBLE*** This is a descriptive explanation of what happens to flow when length of the vessel is doubled and radius and viscosity are held constant.
What is flow reduces by half. When the length of the vessel increases the flow is half of what is was previously. (tin can example in notes)
300
When the resistance is increased and the pressure drop is held constant, this happens to flow.
What is decrease in flow (Q) (R=Delta P/Q)
300
During Inspiration the diaphragm moves down causing this in the abdominal cavity (increase or decrease), this in the abdominal cavity, and the IVC collapses impeding this from the lower extremities.
What is decrease in chest pressure, increase in abdominal pressure, and venous return from the legs is impeded
400
Venous Ulcers occur because of increased venous pressure and volumes caused by distended capillary beds. This is velocities role in Venous ulcerations
What is decreased velocity. If volume goes up, pressure goes up (volume=pressure), if pressure goes up then velocity must go down (pressure=1/velocity). When the blood is stagnant and sits without moving quickly this causes ulceration.
400
This is the explanation of what happens to hydrostatic pressure when blood moves further away and below from the point of reference.
What is an increase in the hydrostatic pressure. Because the total height of a column increases hydrostatic pressure. Because we are below the point of reference our value will be positive (gravity).
400
Ohm's law states that I=voltage/resistance. The I stands for this.
What is current.
400
When the resistance is increased and the pressure drop is held constant, this happens to flow.
What is decrease in flow (Q) (R=Delta P/Q)
400
***DAILY DOUBLE*** The property of a fluid that resists the force tending to cause fluid to flow
What is Viscosity
500
This is the description of the uterus, IVC/Iliac veins of why during pregnancy women can get varicose veins or venous stasis ulcers
What is increased venous pressure caused by the uterus compressing the IVC and iliac veins. This increase in pressure decreases velocity. Blood sits.
500
The approximate hydrostatic pressure in mmHg at the ankles of an average person who is standing upright.
What is ~+100 mmHg
500
This is the explanation and equation that tells us why Velocity is slowest in capillaries allowing for proper exchange of nutrients and oxygen.
What is V=Q/A. Total cross-sectional area is highest in capillaries (think of cough drop in mouth). More area = less velocity so the tissues have enough time to absorb the necessary nutrients.
500
The description each of the four types of arterial blood flow listed on the diagram that will be projected
What is 1. Plug flow, 2. laminar/parabolic flow, 3. Disturbed flow, 4. Turbulent flow.
500
This is the explanation of the role the calf muscle plays in aiding venous circulation
What is the venous calf pump propels blood back to the IVC by contracting and forcing blood up through the leg. One way valve help prevent blood from regurgitating back down the leg.
M
e
n
u