Vascular Access Surgery in Renal Failure
VASCULAR ACCESS SURGERY IN RENAL (KIDNEY) FAILURE
Patients who are undergoing hemodialysis require a vascular access for the blood to be circulated during the dialysis.
Vascular access surgery is a surgically created vein used to remove and return blood during hemodialysis, usually by an arteriovenous (AV) fistula as a connection, made of an artery to a vein. This connection created surgically should provide good blood flow for dialysis.
In this country, vascular access surgery for kidney failure is done by the urologists, vascular surgeons, plastic surgeons and hand surgeons.
There are 3 components of a well-functioning AV fistula:
- Inflow artery
- Needle-stick segment (the conduit)
- Native outflow
An AV fistula normally requires about 2 to 3 months for it to develop and mature to be adequate for it to be used, before the patient can use it for hemodialysis.
A matured AV fistula.
If an AV fistula fails to mature after surgery, the surgeon must repeat the procedure again at a different site or hand, after determining the cause of the failure to mature.
Various complications or risks may be associated with the construction of vascular access which include:
- Infection
- Fluid collection – hematoma (blood collection), seroma or lymphocele (lymphatic fluid)
- Bleeding
- Vein stenosis
- Thrombosis (clotting within the vascular access – either early or late)
- Difficulty cannulating – due to deep situation of the vascular access, obesity, non-maturation of the vascular access
- Failure to mature properly – due to narrowing of the anastomosis, clot formation at the site, or sometimes even central vein stenosis and poor flow of the vascular access
- Aneurysm (dilatation of the access) and pseudoaneurysm
- Vascular steal syndrome – due to arterial insufficiency as a result of diversion of blood
- Neuropathy – including ischemic neuropathy, entrapment neuropathy as well as ischemic monomelic neuropathy
At times post-operatively, the vascular access may require Doppler ultrasound to assess the cause of poor flow or failure, or even at times may require a venogram or fistulogram.