Hemodynamics Dr. Raynes

Question 1

What is Hemodynamics?

Answer 1

The principle that govern blood flow in the cardiovascular system (transport of blood throughout the body)

Question 2

Purpose of the capillaries?

Answer 2

To exchange nutrients, ions, gases, etc between the aorta and the vena cava

Question 3

Arteries:

Answer 3

Will deliver OXYGENATED blood to the organs
** Stressed volume

Question 4

What is the exception for the pulmonary artery ?

Answer 4

Blood will not be oxygenated , will carry DEOXYGENATED blood

Question 5

T/F: Arteries have thick muscular walls

Answer 5

True, due to being under the highest pressure in the vasculature

Question 6

Arterioles:

Answer 6

-Will deliver oxygenated blood
-Smallest branches of the arteries
-Highest resistance in the vasculature to blood flow> due to their small size
-Site where resistance to blood flow can be changed by sympathetic nerve activity, catecholamines
-Located in different organs

Question 7

Where is the pulmonary artery located?

Answer 7

Right side of the heart. Will carry deoxygenated blood

Question 8

Why are the artery thicker and under the highest pressure?

Answer 8

Because they receive blood directly from the heart

Question 9

What are the walls of the arteries made from?

Answer 9

Elastic fibers. Helps them be able to contract

Question 10

Alpha 1 receptors:

Answer 10

Found in the arterioles of the skin, splenic nerve, renal circulation. Excitatory response

Question 11

Alpha 2:

Answer 11

Inhibitory receptor: I.e. when a catecholamine interact with a alpha 2 receptor, there will be dilation of that blood vessel

Question 12

Beta 1:

Answer 12

Found in the heart.

Question 13

Beta 2:

Answer 13

Found in the skeletal and smooth muscles. Excitatory response. I.e. Dilation of lungs

Question 14

Capillaries:

Answer 14

-Thin walled
- Site of nutrient and gas exchange
-Sympathetic will have a response on capillaries
- Have the ability to contract and dilate
-Lined by smoothed muscles

Question 15

Veins:

Answer 15

-Will carry deoxygenated blood> EXCEPT in the pulmonary vein (will carry oxygenated blood; left side of heart)
-Thin walled (large capacity to hold blood)
-Blood will be under low pressure
-Unstressed volume

Question 16

Which vessel has the highest cross sectional area?

Answer 16

Capillaries due the anatomical structure and the wall being thiner

Question 17

Which vessel has the lowest cross sectional area?

Answer 17

Aorta due to the wall being thicker.

Question 18

Velocity of blood flow:

Answer 18

v=Q/A
v= velocity of blood flow
Q=Flow
A=Cross sectional area

Question 19

Relationship between blood flow, pressure, and resistance

Answer 19

Q= ∆ P/R

Q=Flow
P=Pressure difference
R=Resistance

Question 20

Poiseuille equation:

Question 21

Series resistance:

Answer 21

Sequence distribution of blood flow

Question 22

Parallel blood flow:

Answer 22

Simultaneous distribution of blood flow

Question 23

Mean arterial pressure:

Answer 23

Diastolic pressure + 1/3 (systolic pressure-diastolic pressure)

Question 24

Pulmonary wedge pressure:

Answer 24

Pressure used from the left atrial pressure to measure the left side of the heart (from the left atrium)

Question 25

T/F: Cardiac output of the left side of the heart and right side of the heart are equal under normal physiological conditions

Answer 25

True