Dialysis Vascular

Question 1

good flow fistula

Answer 1

> 800 ml/min

Question 2

typical fistula velocity

Answer 2

150-300 cm/sec PSV

60-200 cm/sec EDV

Question 3

associated pseudoaneurysms

Answer 3

often multiple pedicle with to and fro pattern

Question 4

early stenosis of fistula

Answer 4

500-800 ml/min

Question 5

distal native artery

Answer 5

retrograde flow due to arterial steal from AVF

Question 6

site of 80% stenosis/thrombosis of AVF

Answer 6

venous anastomosis

Question 7

> 50% AVF stenosis at anastomosis

Answer 7

> 400 cm/sec

> 3.0 velocity ratio

visible narrowing

Question 8

> 50 % AVF stenosis at venous anastomosis

Answer 8

PSV > 300 cm/sec velocity

ratio > 2.0

visible defect

valve,

narrowing,

intimal change

Question 9

efferent vein velocity

Answer 9

30-100 cm/sec

pulsatile

Question 10

rule of 6

Answer 10

6 mm wide

6 mm deep

6 weeks to mature

> 600 ml/min flow

Question 11

evaluation prior to graft

Answer 11

exclude subclavian thrombosis exclude steal

Question 12

volume flow

Answer 12

TAV (time average velocity) x area x 60 area =

(1/2 d)2/pi measure in straight area

Question 13

vein diameters for mapping `

Answer 13

2-2.5 mm

Question 14

common site of venous thrombosis with AV fistula

Answer 14

subclavian

Question 15

understand afferent artery steal

Answer 15

compression reverses flow in afferent artery or compression makes waveforms look normal

Question 16

textbook: flow reversal in the inflow artery distal to anastomosis

Answer 16

indicates arterial steal