Chapter 11: Duplex/color flow imaging UE Flashcards
purpose of duplex imaging of upper extremities
localize stenosis/occlusion eval degree of stenosis visualize any aneurysm hemodyalisis access or arterial bypass graft site detect AVF's
patient positioning for UE duplex
pt supine
extremity close to you
extremity 45 degree angle from body and externally rotated “pledge position”
what is duplex scanning
combination of real time B mode gray scale and doppler spectral analysis
what is the sample size for acquiring pulsed doppler information
1-1.5mm
main use for UE doopler
eval for dialysis access graft
uncommon for UE stenosis/occlusion
when looking to assess for hemodyalisis graft where do you start
feel for thrill
evaluation of hemodyalisis graft: what do you doppler
inflow artery arterial anastomosis body of graft venous anastomosis outflow vein
what should you assess for when looking at hemodialysis graft
aneyrysms
puncture sites
peri graft fluid
look for color and turbulance
dialysis graft examples:
Brescia-Cimino fistula
straight AVF
looped AVF
synthetic graft
Brescia-Cimino fistula
fistula of radial artery(inflow) and cephalic vein (outflow)
Straight AVF graft
from brachial artery to axillary vein
ulnar artery aneuryms can results from
using palm as a hammer
subclavian artery aneurysms are associated with
embolization to the digits
hemodilaysis graft PSV and EDV
can vary, normally elevated
low PSV in graft site could mean
arterial inflow problems
most common sites for stenosis of hemodialysis graft site
venous anastomosis and outflow vein
caused by increase arterial pressure or intimal hyperplasia
large blood volumes shunted from arterial to venous system can cause
increased venous return which leads to CHF
Steal syndrome from hemodialysis graft site is caused by
distal arterial blood flow is reversed into the venous circulation
steal syndrome can cause pain where
hands and fingers on exertion
with steal syndrome how with the hand look
pallor and coolness of skin distal to shunt
to assess for possible steal of graft site:
use PPG to eval flow in at least 2 digits one at a time
apply manual pressure to dialysis access and retake PPG tracings/pressures
when assessing for a steal, if flow to the digits improves
there is a steal
when assessing for a steal, if flow to the digits does not improve
there is not a steal
