Fluid Dynamics Part 2

Question 1

What are the parts of the waveform?

Answer 1

A	Early Systole
B 	Peak Systolic
C	Late Systole		      
D	Early Diastole		     
E 	Late Diastole

Question 2

What is systole flow?

Answer 2

Blood pressure has built up in left ventricle

Forward flow through the aorta & other arteries

Question 3

What is peak systole?

Answer 3

Maximum ventricular contraction and blood pushed to its peak

Question 4

What is late systole?

Answer 4

reversal of flow

Question 5

What is diastole?

Answer 5

Flow moves forward-a coming out of late systole until it hits the pressure of the next oncoming wave and then reverses direction
Diastole is characteristic of blood supplying low resistant beds

Question 6

Where are these branches going?

Answer 6

Depending on what the branches of the aorta are feeding they will produce a certain type of waveform
All arterial waveforms are somewhat alike but depending on whether they are feeding a high or low resistance organ will have different wave form

Question 7

What is low resistance?

Answer 7

Low resistance organs – have lots of blood flow – do not resist blood coming in
Liver, kidney and spleen
Fed by suprarenal branches which would be the celiac, splenic, and hepatic
Also renal arteries are low resistance because feeding the kidneys

Question 8

What is high resistance?

Answer 8

High resistance organs – not as needy for blood, resist some blood flow
Stomach, small intestines- changes when we eat
Fed by SMA
Small intestines and stomach
IMA also because it feeds the GI system which is high resistance

Question 9

What are examples of low resistance?

Answer 9

Forward, steady, continuous flow
Dilated vascular bed
ICA
Vertebral
Renal
Celiac
Splenic
Hepatic

Question 10

What are examples of high resistance?

Answer 10

Pulsatile, reversal component
Triphasic or biphasic
ECA
Subclavian
Aorta
Iliac
Extremities
SMA - fasting

Question 11

What do low resistance waveforms look like?

Answer 11

Systolic peak followed by a diastolic forward flow waveform

Question 12

What is the number one characteristic of low resisitive waveform?

Answer 12

Number one characteristics of a low resistance waveform is the diastolic component (forward flow)
High end diastolic meaning above the baseline.

Question 13

What do high resistance waveforms look like?

Answer 13

Triphasic – systole, reversed flow and absence or very little forward diastolic flow

Question 14

What is vasodilation? and examples

Answer 14

Vasodilation – decreases flow reversal in small and medium vessels
Exercise
Heat
Pathological states – distal to stenosis and proximal to stenosis due to increased resistance and arteriovenous fistulas

Question 15

What is vasoconstriction?

Answer 15

Vasoconstriction – increases flow reversal in small and medium vessels
Cold

Question 16

What happens when you exercise?

Answer 16

Most effective method for vasodilation
Vessels becomes larger
Resistance decreases
Perfusion increases
Decreases flow reversal

Question 17

What questions to ask for patients who present with vasodilation?

Answer 17

Has your patient exercised recently?
Has your patient been in warm temperatures?
What are the normal Doppler waveforms?

Question 18

What happens proximal to a stenosis?

Answer 18

Waveform is dampened
Not disturbed
tardus parvus waveform

Question 19

What happens at the stenosis?

Answer 19

At level of stenosis
Higher velocities
Pressure decreases
Disorganized flow

Question 20

What happens distal to stenosis?

Answer 20

Distal to stenosis
Post stenotic turbulence
Disturbed/chaotic flow
Bidirectional

Question 21

What are collaterals?

Answer 21

Collateral flow taking over for stenosis or occlusion
Flow is present but possibly not normal for site
Increased volume
Increased velocity
Waveform changes
Reversed flow