Hemodynamics

Question 0

what are the 2 types of directional flow

Answer 0

forward and reverse flow

Question 1

what is hemodynamics

Answer 1

blood movement

study of blood flow or the circulation

Question 2

what is circulation

Answer 2

flow of blood through a closed system

Question 3

describe arterial system

Answer 3

multibranched elastic conduit that carries blood away from the heart

the heart is the pump through contractions and relaxations

Question 4

when the heart contracts, the intended flow is forward into the _____ and ______ artery

Answer 4

aorta and pulmonary artery

Question 5

blood flow is in _____

ability to do _____

Answer 5

motion

work

Question 6

what is conservation of energy

Answer 6

energy is never lost only converts to another form

Question 7

potential - _____ energy

kinetic - _____ energy

total energy = _____ + _____

Answer 7

resting - static

motion - dynamic

potential + kinetic

Question 8

what is work

Answer 8

amount of energy transferred over time

units - joules

Question 9

what is power

Answer 9

concentration of force per unit area

force behind fluid flow

Question 10

what is hydrostatic pressure

Answer 10

pressure exerted by a fluid due to its weight or force per unit area

measured related to the heart

units - mmHG

Question 11

factors of hydrostatic pressure

Answer 11

height of the column of blood

density of the fluid

force of gravity

Question 12

what is energy or pressure gradient

Answer 12

pressure difference in order for blood to move

**flow is from high to low pressure

Question 13

pressure in the left ventricle rises and blood is ejected out of the _____ valve into the _____

Answer 13

aortic valve

aorta

Question 14

what is stroke volume

Answer 14

amount of blood ejected

equal to the difference between end-diastolic volume and end-systolic volume

Question 15

heart pump generates _____ to move the blood

Answer 15

pressure (potential energy)

Question 16

pressure gradient is the same as pressure _____

Answer 16

difference

**necessary to maintain flow

Question 17

greater the pressure gradient, the _____ the flow rate

Answer 17

greater

Question 18

loss in flow is due to…

Answer 18

friction

resistance

Question 19

greater the resistance, the _____ the flow

Answer 19

lower

Question 20

what is viscosity (thickness)

Answer 20

the resistance to flow

units - poise or kilogram per meter second

Question 21

what is laminar flow

Answer 21

normal flow

layers with the highest velocities in the center stream

Question 22

types of laminar flow

Answer 22

parabolic - shape of a bullet

plug - same velocity

Question 23

energy is lost in the form of _____ due to friction

Answer 23

heat

Question 24

what is Poiseuille's Law

Answer 24

flow rate through a cylindrical tube is directly proportional to pressure gradient, the driving pressure along the tube, and the 4th power of the radius flow is inversely proportional to length of the tube and viscosity of the liquid

Question 25

Poiseuille's Law - 3 primary factors that determine the resistance to blood flow within a single vessel

Answer 25

vessel diameter (radius) - MOST IMPORTANT vessel length viscosity of the blood

Question 26

Poiseuille's Law relationships: pressure and flow rate && diameter and flow rate

Answer 26

directly related

Question 27

Poiseuille's Law relationships: length and flow rate && viscosity and flow rate && resistance and flow rate

Answer 27

indirectly related

Question 28

Poiseuille's Law radius decrease, resistance _____, flow rate _____ viscosity increases, resistance _____, flow rate _____ length increases, resistance _____, flow rate _____

Answer 28

increases, decreases (for all 3)

Question 29

resistance of the arterioles accounts for about _____ of the resistance in systemic circulation

Answer 29

half

Question 30

what is Bernoulli's Principle

Answer 30

velocity and pressure are inversely related high velocity - low pressure low velocity - high pressure relationship in a stenosis

Question 31

peripheral resistance low resistance flow - _____ diastolic flow high resistance flow - _____ diastolic flow

Answer 31

high low **look at images on slide 35

Question 32

stenotic vessel might present with what

Answer 32

reduction in volume flow bruits spectral broadening

Question 33

what are the 2 types of flow

Answer 33

laminar - parabolic or disturbed turbulent - chaotic or eddies

Question 34

what is Reynold's

Answer 34

shows turbulance ***above 2000 = turbulent flow

Question 35

what can increase the Reynold's number

Answer 35

increased flow speed and vessel radius

Question 36

what is pulsatile flow

Answer 36

non steady flow with acceleration and deceleration over the cardiac cycle

Question 37

_____ or _____ produces disturbed or turbulent flow

Answer 37

narrowing or stenosis

Question 38

what is the continuity rule

Answer 38

flow rate must be constant

Question 39

flow speed _____ at a stenosis and turbulence can occur _____

Answer 39

increases distally

Question 40

what is bruit

Answer 40

sound produced by turbulence

Question 41

what is occlusion

Answer 41

blocked vessel - no flow - no sound (bruit)

Question 42

at the stenosis the pressure is _____...

Answer 42

less

Question 43

pressure difference - fluid _____

Answer 43

accelerates

Question 44

decreased pressure in high flow speed = _____ effect

Answer 44

Bernoulli

Question 45

what are the 3 waveforms

Answer 45

triphasic biphasic monophasic

Question 46

what is triphasic

Answer 46

high pulsatility sharp upstroke in systole forward flow

Question 47

what is biphasic flow

Answer 47

moderate pulsatility

Question 48

what is monophasic flow

Answer 48

low pulsatility broad systolic peaks