Dialysis access, also known as vascular access, is the creation of a sustained, long-term opening in a blood vessel to facilitate hemodialysis, the conventional form of dialysis. Hemodialysis uses a specialized machine called a dialyzer to clean your blood.
During the treatment, two separate tubes (outflow and inflow) are connected to the access site. A few ounces at a time, your blood flows out of the access site and into the dialyzer, where it travels through thin fibers that filter out waste and excess fluids.
The clean blood then flows back into your body through the access site via another tube.
Dialysis access should be in place and fully healed several weeks or even months before the first hemodialysis treatment. There are three main types of vascular access sites; two are designed for long-term use, and one is intended for short-term use.
Considered the best long-term dialysis access opening because it’s less prone to clotting and carries a low risk of infection, an AV fistula involves taking part of a vein from your arm or leg and grafting it onto an artery in your arm.
Also called a dialysis fistula, this approach causes the sewn-in vein to enlarge and become thicker, much like an artery. Although it can take 1-4 months to heal before it’s ready for use, an AV fistula makes needle insertion easy during treatment.
An AV graft is a dialysis access that uses a soft tube (prosthetic graft) to join an artery and a vein in your arm. If your blood vessels aren’t strong or large enough for fistula surgery, an AV graft is the next best long-term access option.
An AV graft heals more quickly and can be ready for use in as little as 3-6 weeks. Because it involves a prosthetic, however, an AV graft is more vulnerable to infection than an AV fistula. During hemodialysis treatment, the needles are inserted directly into the graft.
A central venous catheter is a soft tube that’s placed in a large vein, usually in the neck. While it can be used immediately, this type of dialysis access is intended for short-term hemodialysis because the risk of infection is relatively high.
A venous catheter is often used when kidney disease has progressed quickly, and a patient can’t wait for the placement of an AV fistula or an AV graft before starting hemodialysis.
No matter which type of dialysis access you have, routine maintenance and care can help it last as long as possible. The team at Advanced Vascular & Vein Associates provides detailed daily care instructions, and they also offer as-needed maintenance should a problem arise.
Dialysis access problems to watch out for include:
Signs of infection include redness, warmth, swelling, pain, oozing pus, and fever. Catheters and grafts are more likely to become infected than fistulas.
Clots can form in your access and impede blood flow. Grafts and catheters are more likely to be affected by a blood clot blockage than fistulas.
Sometimes, the blood vessels involved in an AV fistula or AV graft become narrow. Known as stenosis, this condition slows the flow of blood through the access. Catheters aren’t affected by this problem.
To learn more about the dialysis access services at Advanced Vascular & Vein Associates, call the office, or schedule an appointment online today.