LE and UE Doppler Segmental Pressures

Question 1

Limitations of Doppler segmental pressures?

Answer 1

a) Cannot discriminate between stenosis and occlusion, precise area, or discriminate between CFA and external iliac disease.
b) Calcified vessels render falsely elevated Doppler pressures
c) Uncompensated CHF may result in decreased ABI
d) Artifactually elevated high thigh pressures when narrow cuff used on thigh
e) Difficult to interpret in presence of multi-level disease

Question 2

Patient should rest for how long prior to exam?

Answer 2

20 minutes

Question 3

How is cuff artifact created?

Answer 3

cuff too large, BP falsely lower

cuff too narrow, BP falsely higher

Question 4

Width of the cuff should be about what % greater than the diameter of the limb?

Answer 4

20%

Question 5

Order of segmental pressures?

Answer 5

brachial, ankle (PTA and DPA), calf (use highest ankle pressure for the rest of the leg), above the knee, high thigh

Question 6

Why is it important to inflate from the ankle up instead of the other way?

Answer 6

there isn’t enough time for the blood to completely flow normally into the leg so the obtained BP would likely be falsely lower than it should be.

Question 7

TO obtain complete cessation of blood flow the cuffs should be inflated to what pressure beyond the last audible Doppler arterial signal or to what pressure above the highest brachial pressure?

Answer 7

20-30 mmHg

Question 8

If pressure measurements need to be repeated the cuff should be fully deflated for how long prior to repeat inflation?

Answer 8

1 minute

Question 9

How is an ABI calculated?

Answer 9

divide ankle pressure by the higher of the two brachial pressures

Question 10

Another term for ABI?

Answer 10

ankle/arm pressure index

Question 11

ABI numbers

Answer 11

>1.0 = normal
>0.9-1.0 = asymptomatic or mild disease
0.5-0.9 = claudication (moderate)

Question 12

Incompressible vessels considered to have an ABI greater than what?

Answer 12

1.3-1.5

Question 13

Some authors feel an absolute ankle pressure of what, rather than the ABI of .5 has stronger weight for predicting symptoms at rest.

Question 14

Strandness’ work suggests that an ABI of > _____ represents single segment disease;

Answer 14

0.5

Question 15

A segmental pressure drop between two consecutive levels suggests obstruction?

Answer 15

> 30 mmHg

Question 16

In the 4 cuff technique the thigh cuff is normally what pressure higher than the highest brachial pressure?

Answer 16

> 30 mmHg

The AK and BK pressures should be at least the same as the highest brachial.

Question 17

In the 3 cuff technique the thigh pressure is similar to what?

Answer 17

the highest brachial pressure

Question 18

Toe pressures of

Answer 18

30 mmHg

Question 19

In diabetic patients what pressure is most reliable?

Answer 19

toe pressures

Question 20

Exercise is useful during testing how?

Answer 20

a) compare resting values to those after exercise
b) helps differentiate between true and pseudo-claudication
c) determine presence/absence of collaterals

Question 21

Contradictions of exercise include?

Answer 21

shortness of breath, hypertension, cardiac problems, stroke, walking problems

Question 22

Technique for exercise after resting exam?

Answer 22

a) patient walks on treadmill at a treadmill at

Question 23

post-exercise ABI’s normal and abnormal

Answer 23

a) Normal: ABI increases
b) Abnormal: ABI decreases minimally or to a severe amount
c) With drop after exercise, pressures obtained every 2 minutes until pre-exercise pressures are attained

Question 24

What level of disease takes 2 to 6 minutes for the ABI’s to increase back to resting levels after they dropped to low or unrecordable levels after exercise?

Answer 24

single level disease

Question 25

What level disease takes 6 to 12 minutes for the ABI’s to increase back to resting levels after they remained low or at unrecordable levels after exercise?

Answer 25

Multi-level disease

Question 26

Reactive hyperemia alternative method to exercise, what does it involve?

Answer 26

Bilateral thigh cuffs inflated to suprasystolic pressure levels, usually 20-30 mmHg above the higher brachial BP, maintaining the pressure 3 to 5 minutes.
Produces ischemia and vasodilatation distal to the occluding cuffs.

Question 27

With reactive hyperemia normal limbs may show a transient drop of?

Answer 27

17-34%

Question 28

In reactive hyperemia there is a > ______ % pressure drop in ankle pressure with multi-level disease.

Answer 28

50%

Question 29

What is the Allen test used for?

Answer 29

To evaluate patency of the palmar arch

Question 30

How is the Allen test preformed?

Answer 30

a) manual compression of radial artery by technologist while patient clenches fist for less than 1 minute inducing pallor.
b) patient relaxes hand while continuing manual compression of the radial artery.
c) PPG on the index finger to document arterial pulsations before and after the clenched fist

Question 31

Interpretation of Allen test of normal and abnormal?

Answer 31

Normal: reappearance of normal color to indicate ulnar flow to palmar arch
Abnormal: color does not reappear indicating ulnar artery occlusion or palmar arch obstruction

Question 32

A > 15-20 mmHg drop from upper arm to forearm suggests?

Answer 32

a) brachial artery obstruction distal to the upper cuff
b) obstruction in both radial and ulnar arteries
c) obstruction in single forearm artery which had decreased pressure

Question 33

A _____ mmHg difference from one brachial pressure to the other, suggests a > _____ % stenosis of subclavian artery and/or vessel under the cuff.

Answer 33

15-20 mmHg

50%

Question 34

A difference of > _____ mmHg between radial and ulnar pressures suggests obstruction in vessel with lower pressure.

Answer 34

20 mmHg