hemodynamics

Question 1

what factors interfere with blood flow

Answer 1

viscosity
length
and diameter

Question 2

large vessels have

Answer 2

less resistance
more flow
more pressure

Question 3

smaller vessels have

Answer 3

more resistance
less flow
less pressure

Question 4

plug flow

Answer 4

concentric layers all travel at the same time and the same velocity

Question 5

parabolic flow

Answer 5

flow is highest in the center

Question 6

turbulent flow

Answer 6

noisy and causes a murmur

highest velocity is at the site of obstruction

Question 7

reynolds number

Answer 7

less than 1500 is laminar flow

more than 2000 is turbulent flow

Question 8

poiseuilles law of hemodynamics

Answer 8

vessel length and viscosity remain constant

vessel radius changes

Question 9

blood pressure

Answer 9

force exerted by blood against the walls of the vessels

flow occurs from higher pressure to lower pressure

Question 10

proximal pressure is …

Answer 10

always higher than the distal pressure

Question 11

pressure in a stenosis is

Answer 11

the lowest

Question 12

bernoullis principle

Answer 12

Question 13

bernoulli equation

Answer 13

Question 14

phase 1 of cardiac cycle: early diastole /rapid filling

Answer 14

• MV & TV open due to increase pressures in LA and RA
• 70% passive filling
• LV and RV expand

Question 15

phase 2 - late diastole / atrial contraction

Answer 15

LA and RA contract due stimulation forces 30% of blood into the ventricles
lv pressures begins to increase
active filling

Question 16

phase 3 : IVCT (isovolumetric contraction)

Answer 16

brief period when MV and TV close and the AV and PV open
all 4 valves are closed
ventricular pressure increase

Question 17

phase 4 ventricular systole

Answer 17

LV and RV pressures exceed the pressures in the Aorta and pulmonary artery causing the AV and PV to open
atria are also filling with blood

Question 18

phase 5 IVRT : isovolumetric relaxation time

Answer 18

the AV and PV close because of decrease in pressures