Exam 2: Lecture 15: Hemodynamics 2 Flashcards
what describes the blood flow in the cardiovascular system
laminar (streamlined)
Where is the velocity of blood flow highest and where is it the lowest in the blood vessel
Highest is towards the center of the vessel and lowest is towards the walls of the vessels
What is the velocity of flow towards the wall
Zero
What is the velocity of flow towards the wall of the vessel
Maximal
What an irregularity occurs in a blood vessel (blood clot, etc.) the laminar stream is disrupted and blood may become _______
Turbulent
Is laminar flow silent or audible
Silent
Is turbulent Flow silent or audible
Audible
What is used in the ausculatory measurement of blood pressure are caused by turbulent flow
Korotkoff sounds
What term is used to describe blood vessel stenosis and cardiac valve disease can cause turbulent flow and often are accompanied by audible vibrations
Murmurs
What is the cut off on Reynolds number that says blood flow is laminar
2000
If Reynolds number is greater than this value we except turbulent flow
2000
What are the major influences on Reynolds number in the cardiovascular system
Changes in blood viscosity and velocity if blood flow
What term is associated with a decreased hemotracit and because of turbulent blood flow causes functional murmurs
Anemia
What term is associated with blood clots in the lumen of a vessel. This narrows the diameter of the blood vessel, which causes an increase in blood velocity at the site
Thrombi
What its the consequence of the fact that blood travels at different velocities within a blood vessel
Shear
Where is shear the highest in the blood vessel
Towards the blood vessel wall
Where is shear the lowest in the blood vessel
Towards the center of the blood vessel
Define compliance or capacitance of a blood vessel
Volume of blood the vessel can hold at a given pressure
What does it mean when compliance is higher in the vessel
The more blood it can hold
What describes how the volume of blood contained in a vessel changes for a given change in pressure
Compliance
Do veins or arteries have a higher compliance
Veins
Do veins or arteries have a lower compliance
Arteries
What does it mean that compliance of the veins is high
The veins can hold larger volumes of blood at low pressure
What does it mean that the compliance of the arteries is lower
They hold less volume of blood but at a higher blood pressure
Are the veins or arteries the most compliant and contain unstressed volume (large volume under low pressure)
Veins
Are the veins or arteries the less compliant and contain the stressed volume (low volume under high pressure)
Arteries
What happens if the compliance of capacitance of the veins increase
Increase in the volume in veins they can hold
Blood shift from the arteries to the veins
Unstressed volume increases and stressed volume decreases
As you age what happens to the compliance of blood vessels
They decrease