Bzzz…. Bzzz…. Bzzz…. Bzzz….
Dr. Maha Al Marashi
KM. 60 Female
Elective admission on into Beaumont Hospital under the care of nephrology service with poor flow through left femoral perma-cath which was inserted.
KM. 60 Female
BGHx: IDDM 1982
Diabetic retinopathy Diabetic neuropathy ESRF on haemodialysis alternate days
HTN Left subclavian vein stenosis
KM. 60 Female Left brachio-cephalic AVF
Left subclavian stenosis Right brachio-basilic AVF
Fistuloplasty Superficialisation
Right upper limb graft Venoplasty right brachio-basilic AVF Right femoral permacath
KM. 60 Female
Doppler lower limbs: Patent veins which may be suitable
for fistula/ graft.
KM. 60 Female Left SFA-SFV groin
PTFE graft loop AVF
Sartorious muscle mobilised medially and laterally to expose SFV + SFA respectively
Venaflo graft tunneled in loop to lower thigh.
KM. 60 Female Parachute
anastamosis to SFV and SFA.
Heparin flushing. Haemostasis. Closure in layers.
KM. 60 Female
Post-operatively: Good bruit Good signals Left foot pink No haematoma No pain
Arterio-Venous Fistula
History Many advances in the
treatment of kidney failure have been seen since the first attempts at dialysis treatments were made in the 1920s.
The first breakthrough came in 1965 with the development of the AV fistula at the Bronx Veteran's Administration Hospital in New York by Kenneth Charles Appell.
The development of the AV fistula has marked an important advance, allowing effective treatment for longer periods of time.
Pathophysiology Normal blood flow in the brachial
artery is 85 to 110 mL/min. After the creation of a fistula, the blood flow increases to 400 to 500 mL/min immediately, and 700 to 1,000 mL/min within 1 month.
A bracheocephalic fistula above the elbow has a greater flow rate than a radiocephalic fistula at the wrist.
Both the artery and the vein dilate and elongate in response to the greater blood flow and shear stress, but the vein dilates more and becomes "arterialized".
When the vein is large enough to allow cannulation, the fistula is defined as "mature."
An arteriovenous fistula can increase preload.
Venous Access for Haemodialysis AV Fistula AV Graft Venous catheter (permacath)
AV Fistula “Gold Standard” It has a lower risk of infection than grafts or
catheters It has a lower tendency to clot than grafts or
catheters It allows for greater blood flow, increasing the
effectiveness of hemodialysis as well as reducing treatment time
It stays functional for longer than other access types; in some cases a well-formed fistula can last for decades
Fistulas are usually less expensive to maintain than synthetic accesses
Pre-op Diagnostic Tests
Duplex arteries and superficial veins
Venogram MRA/MRV
Surgical Techniques: Native
A, Normal anatomy of the right antecubital fossa, showing the cephalic vein (CV), median antecubital vein (MACV), basilic vein (BV), brachial artery (BA), radial artery (RA), and ulnar artery (UA).
B, Brachiocephalic arteriovenous fistula.
C, Brachiobasilic arteriovenous fistula.
D, Brachial artery–to–median antecubital vein arteriovenous fistula
Surgical Techniques: Graft Radial graft –
formed in the wrist (radio-cephalic)
Brachial graft – formed near the elbow (brachio-cephalic)
Leg graft – formed in the thigh
Neck graft – ‘necklace graft’
Complications
Infection Thrombosis Stenosis Aneurysm/ pseudo-aneurysm Steel syndrome Limb ischaemia
Intervention
Angioplasty Stenting Thrombectomy Tie-off Removal of infected graft.
Aftercare Making sure the access is checked before each
treatment. Not allowing blood pressure to be taken on the
access arm. Checking the pulse in the access every day. Keeping the access clean at all times. Using the access site only for dialysis. Being careful not to bump or cut the access. Not wearing tight jewelry or clothing near or
over the access site. Not lifting heavy objects or putting pressure on
the access arm. Sleeping with the access arm free, not under
the head or body.
Conclusion AV fistula ‘gold standard’ for
venous access for haemodialysis. Commonly radio-cephalic in non-
dominant arm Approximately 6/52 to ‘mature’ May use graft material: mature
faster but higher rate of infection Palpate for thrill and auscultate for
bruit/ bzzz…