Class 13: Duplex Imaging of UEA & Hemodialysis Grafts

Question 1

what are the normal waveforms for the upper extremity arteries?

Answer 1

triphasic or biphasic. may be monophasic if arm has been heated or exercised

Question 2

at the stenosis in the UE, you can expect to see (high/low) velocity

Answer 2

high velocity

Question 3

what is hemodialysis?

Answer 3

a treatment used in renal failure

Question 4

what is a dialyzer?

Answer 4

machine used during hemodialysis that removes waste products from blood through a filter – acts like the kidneys

Question 5

how often is hemodialysis treatment?

Answer 5

typically 3x/week for 3-5 hours

Question 6

what is a fistula?

Answer 6

abnormal connection bw artery & vein

Question 7

what is an access graft?

Answer 7

a synthetic material placed between artery & veinn

Question 8

what is an access graft used for?

Answer 8

hemodialysis puncture

Question 9

what is another name for an AV fistula?

Answer 9

brescia-cimino

Question 10

what is the most recommended type of hemodialysis graft?

Answer 10

AV fistula

Question 11

why is the AV fistula the most recommended type of hemodialysis graft?

Answer 11

it provides long-term patency with low complication rates

Question 12

which arteries & veins does an AV fistula connect?

Answer 12

radial artery to cephalic vein
or
ulnar artery to basilic vein

Question 13

what are the other types of grafts made from PTFE?

Answer 13

1. straight grafts
2. looped grafts

Question 14

what is another name for PTFE?

Answer 14

gortex

Question 15

what does PTFE stand for?

Answer 15

polytetrafluoroethylene

Question 16

what artery & vein does the forearm straight graft connect?

Answer 16

radial artery to median antecubital v. or basilic v.

Question 17

what artery & vein does the upper arm reverse straight graft connect?

Answer 17

brachial a. to basilic v.

Question 18

what does the forearm looped graft connect?

Answer 18

brachial artery to cephalic v./ median cubital v./basilic v.

Question 19

what does the upper arm looped graft connect?

Answer 19

brachial a. to axillary v.

Question 20

what does the looped graft in the LE connect?

Answer 20

SFA to GSV

Question 21

what 5 areas do we need to evaluate for grafts?

Answer 21

1. inflow artery
2. PROX anastomotic area
3. within graft
4. DIST anastomotic area
5. outflow vein

Question 22

what are you looking for when evaluating grafts?

Answer 22

• aneurysms
• leaks at puncture sites
• peri-graft fluid collection
• other abnormalities

Question 23

6 graft complications

Answer 23

1. thrombosis/occlusion
2. stenosis
3. arterial steal syndrome
4. venous hypertension
5. aneurysm
6. pseudoaneurysm

Question 24

PSV & EDV velocity & resistance within the graft?

Answer 24

both slightly elevated velocities with low resistance

Question 25

a low PSV within a graft may be due to ____

Answer 25

arterial inflow problems

Question 26

most common sites for stenosis with grafts?

Answer 26

1. venous anastomosis
2. outflow vein

Question 27

what is arterial steal syndrome?

Answer 27

flow is stolen from the distal part of graft

Question 28

what are 3 S&S of arterial steal syndrome?

Answer 28

1. pain with exertion of affected UE
2. pallor of affected UE
3. skin is cool distal to the graft

Question 29

what size is problematic for a pseudoaneurysm for the UE?

Answer 29

> 1 cm

Question 30

what can cause a pseudoaneurysm in the UE?

Answer 30

graft disintegration, problems at the site of graft anastomosis

Question 31

what causes venous hypertension?

Answer 31

• retrograde venous flow
• forearm loop graft with venous stenosis

Question 32

2 S&S with a patient with venous hypertension?

Answer 32

1. hand swelling
2. venous stasis