Arteriovenous (AV) Fistula — The Gold Standard Hemodialysis Access
Once kidney function goes below 10 to 15 percent of normal, dialysis treatments or a kidney transplant are necessary. There are two types of dialysis: hemodialysis and peritoneal dialysis (PD). Both dialysis treatments can replace the kidneys’ function of cleaning the blood of toxins and removing extra fluids.
Hemodialysis cleans blood by removing it from the body and passing it through a dialyzer, or artificial kidney. The type of access a person has is important for getting the best dialysis possible. The ideal access types are arteriovenous (AV) graft and AV fistula.
Arteriovenous (AV) graft for hemodialysis
An arteriovenous (AV) graft is created by connecting a vein to an artery using a soft plastic tube. After the graft heals, hemodialysis is performed by placing one needle in the arterial side and one in the venous side of the graft. The graft allows for increased blood flow.
Arteriovenous (AV) fistula for hemodialysis
A fistula used for hemodialysis is a direct connection of an artery to a vein. Once the fistula is created it’s a natural part of the body. Once the fistula properly matures, it provides an access with good blood flow that can last for decades. It can take weeks to months before the fistula is ready to be used for hemodialysis.
Fistula—the gold standard access
The National Kidney Foundation (NKF), Centers for Medicare and Medicaid Services (CMS) and Dialysis Patient Citizens (DPC) agree fistulas are the best type of vascular access.
A fistula is the “gold standard” because:
- It has a lower risk of infection
- It has a lower tendency to clot
- It allows for greater blood flow and reduces treatment time
- It stays functional longer than other access types
- It’s usually less expensive to maintain
While the AV fistula is the preferred access, some people are unable to have a fistula. If the vascular system is greatly compromised, a fistula may not be attempted. Some of the drawbacks of fistulas are:
- A bulge at the access site
- Lengthy maturation time or never maturing at all
Cleanliness is one way someone on hemodialysis can keep their fistula uninfected. Keep an eye out for infections, which can often be detected when there is pain, tenderness, swelling or redness around the access area. If you notice fever, contact your doctor.
Unrestricted blood flow
Any restriction of blood flow can cause clotting. Here are some tips to help avoid restriction:
- Avoid tight clothing or jewelry over your access area.
- Don’t carry heavy items over your access area.
- Have your blood pressure taken and blood drawn from your non-access arm.
- Don’t sleep with your access arm under your head or pillow.
- Check the pulse in your access daily.
The vibration of blood going through your arm is called the “thrill,” which you should check several times a day. If the “thrill” changes or stops, a blood clot may have formed. If this happens, immediately contact your doctor or dialysis healthcare team.
Using a stethoscope or putting your ear to the access lets you hear the sound of blood flowing through your access. If the sound gains in pitch, your blood vessels could be tightening.
Good needle sticks
The ladder and buttonhole techniques are strategies for using a needle on a fistula, according to the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK).
The ladder technique requires you or your dialysis care provider “stick” the fistula vertically in a different place every time. This is called “climbing,” and it saves you from weakening a certain area by repeatedly sticking it.
With the buttonhole technique, needle sticks are limited to a single site that is used repeatedly and allows for fewer traumas.
If you have questions about your access, please talk to your doctor or dialysis healthcare team.