Vascular Ch. 22 & 30 Flashcards
Central venous access plays a vital role in care of critically ill patients and also used for
intravenous antibiotic therapy, chemotherapy, total parenteral nutrition
Central vascular access devices (VAD) are catheters so the ______ resides in a central vein (_________)
terminal tip, most often superior vena cava
Most common target vein for central VAD
basilic
Initial puncture is made in the vessel and the tip resides in
superior vena cava
Artriocaval junction is
distal 3rd of SVC
What is the volume flow with VAD
high flow volume, 2000 mL/min
Why is the basilic vein preferred for peripheral VAD placement
due to volume flow
Lower extremity veins for VAD placement is more common in
neonates and children
Which vessel is used for access in emergent situations
CFV
Which is right IJV preferred for central VAD placement
has straighter course to heart
External jugular may be used if IJV is occluded, this vessel is
more superficial and tortuous than the IJV
Ultrasound guidance reduces failure of catheter placement as well as complications related to insertion because
non target puncture
With ultrasound, it is important to assess
vessel patency, vessel diameter, relationship of IJV to CCA
What should not be used for cannulation in patients with chronic renal insufficiency or chronic kidney disease. Why
subclavian/upper extremity; preserve for hemodialysis access
Used for central venous access in emergency situations or when other sites are occluded
CFV
Scanning technique and initial assessment
available patent vessels, location, assess size and patency
____ will enlarge with neighboring _____ vein _______ or _______
collateral veins, larger vein, stenosis, thrombus
Once VAD is placed, confirmation of appropriate tip placement is made with
xray
What VAD complications can be reduced by using ultrasound guidance
pneumothorax, AV fistula, infection
If artery is punctured, needle should be immediately removed and pressure applied to reduce chance of
hematoma
Goal is to create an autogenous fistula as ________. Why
far distally as possible in nondominant arm; preserves proximal vessels for potential future access
Why are upper extremities preferred for autogenous access
lower infection rate and easier access
Autogenous fistulas have better
long term patency (40-70%) than synthetic grafts
If arterial system is acceptable (_______ with no significant abnormalities), then proceed to venous system
diameters >2mm
Diameter of veins should be recorded along entire length and must be greater than
2.5mm
You will need to document
depth, wall thickness, calcification, location of thrombus
What arterial vessels should have a diameter greater than 2mm
radial, ulnar, brachial
Vein diameters should be
> 2.5mm
Vein walls should
compress completely
In the venous system, _____ makes the vessel unusable
thrombosis
What is the Brescia-Cimino fistula
cephalic vein connected to distal radial artery at wrist
For AV access, what other distal forearm vessel can be used
basilic instead of cephalic
For AV access, basilic vein must be ____ and _____ to
transposed, juxtaposed, connect to distal artery
Fistula maturity should take
8-12 weeks
B-mode used to assess for what abnormalities
stenotic valves, thrombus, calcifications
For volume flow measurement, what size should your sample volume be
large
In a normal fistula
valves should not be visible, PSV between 150-300 cm/s, volume flow >800mL/min
What is an abnormal finding of AV graft
valve projecting into lumen
Why should a valve projecting into the lumen be evaluated
it can be a source of stenosis development
Stenosis within venous outflow segment usually a result of
intimal hyperplasia
