People with kidney failure need a reliable way into the bloodstream for dialysis. An AV fistula, made by a vascular surgeon, is the most reliable option for long-term hemodialysis. When a fistula is not possible, an AV graft or a permacath is used instead.
Medically reviewed by Dr. Aniruddha Bhuiyan, MCh vascular surgeon. Updated October 2026.
For people with kidney failure, dialysis becomes part of daily life. It removes waste and extra fluid from the body when the kidneys can no longer do it. To work well, dialysis needs a safe and reliable way into the bloodstream, called dialysis access.
So making that access is the job of dialysis access surgery. As vascular surgeons, we create these access points and also keep them working. The first choice is an arteriovenous (AV) fistula. When a fistula is not possible, we use an AV graft or a permacath (a tunnelled catheter).
Permacath or AV fistula, which is better? For long-term dialysis, an AV fistula is the better choice. It uses your own blood vessels, lasts the longest and has the lowest risk of infection, but it needs about 4 to 8 weeks to mature before it can be used. A permacath works the same day, so doctors use it when dialysis is urgent or while a fistula matures. Because a permacath carries a higher risk of infection and blockage, it is best kept as a short-term bridge. An AV graft sits in between and can usually be used within 2 to 3 weeks. See the full comparison.
An AV fistula is a direct surgical join between an artery and a vein, usually in the arm. It is the gold standard for hemodialysis because it uses your own blood vessels. That makes it last longer and cause fewer problems.
The procedure is short, and the surgeon does it under local anesthesia. After surgery, the fistula then takes about 4–8 weeks to mature. In that time the vein grows thicker and stronger, so it can take repeated needles during dialysis.
Kidney specialists and surgeons around the world recommend the AV fistula as the first choice for long-term dialysis. The NHS gives a simple overview of how dialysis works.
| Benefit | Description |
|---|---|
| Long-lasting | Can function for years if well maintained. |
| No artificial material | Made from your body’s natural tissues. |
| Lower infection risk | Much safer than artificial access. |
| Less risk of clotting | Blood flow remains steady. |
| Faster and more efficient dialysis | Better clearance during sessions. |
| Fewer hospital visits | Less prone to emergencies compared to other options. |
First, the surgeon carefully checks your blood vessels:
Doctors call this vessel mapping or vessel planning. It also tells us the best place for your fistula, usually the forearm or upper arm.
Once the surgeon chooses the right spot:
Following surgery, the fistula needs 4 to 8 weeks to mature. During this time:
When the fistula has matured, two needles go into it at each dialysis session. One takes blood out, while the other returns it after filtering.
Some patients cannot have a fistula because of:
For them, we look at the other options below instead.
When your veins are not suitable for a fistula, the next best option is an AV graft.
An AV graft is a soft synthetic tube, made of a medical material called PTFE, that joins an artery to a vein, usually in the upper arm. It acts as a bridge for blood flow, so the dialysis needles go into it just as they would into a fistula.
Still, with good care and regular check-ups, an AV graft can work well for a long time.
Doctors use a permacath when the arms cannot take a fistula or graft, or when the patient needs dialysis straight away.
It is a soft plastic tube placed in a large vein in the chest or thigh, with its tip close to the heart. It runs in a tunnel under the skin, which holds it steady and lowers the risk of infection compared with temporary catheters.
A permacath is a temporary or in-between solution, so we avoid it as a long-term option when we can.
Every patient is different. The choice depends on:
| Feature | AV Fistula | AV Graft | Permacath |
|---|---|---|---|
| Material | Natural (your veins) | Synthetic tube | Plastic catheter |
| Infection Risk | Low | Moderate | High |
| Longevity | Longest | Moderate | Short-term |
| Time to Use | 4–8 weeks | 2–3 weeks | Immediate |
| Insertion Site | Forearm/arm | Arm | Chest/thigh |
| Best For | Long-term dialysis | Poor veins | Urgent use or no access |
Whatever type of access you have, good daily care prevents most problems, so the habits below matter.
We may also check the access with ultrasound from time to time, to see how well it is working and to catch narrowing before it blocks.
As vascular specialists, we focus on:
We want your access to last as long as possible, with few complications and smooth dialysis sessions.
The surgeon makes it from your own artery and vein, so it lasts longer and carries a lower risk of infection and clotting than an AV graft or a permacath.
Usually after 4 to 8 weeks, once the vein has grown thicker and stronger. An AV graft is usually ready within 2 to 3 weeks.
No. The surgeon usually makes a fistula under local anaesthesia through a small cut in the arm.
Keep the area clean and dry and check it daily for swelling, redness or bleeding. Do not sleep on that arm or wear tight clothing over it, and do not allow blood pressure readings or IV lines in that arm.
For long-term dialysis, an AV fistula is better than a permacath. It uses your own artery and vein, lasts longer and has a much lower risk of infection and blockage. A permacath is useful when you need dialysis straight away or when a fistula is not possible, but it works best as a bridge until a fistula or graft is ready.
A permacath can work for several months, sometimes longer. But the longer it stays in, the higher the risk of infection, blockage and narrowing of the vein it sits in. That is why we plan a fistula or graft early, so the catheter can come out as soon as possible.
The surgeon places it under local anaesthesia, usually through the large vein in the neck (the internal jugular vein), with ultrasound guiding the needle. The catheter runs in a tunnel under the skin so it comes out on the upper chest, and a small cuff under the skin holds it in place and helps keep out infection. An X-ray then confirms the tip sits just above the heart. The procedure usually takes under an hour, and dialysis can start through the catheter the same day.
No. A thrill is the buzzing vibration you can feel over a working fistula or graft, caused by fast blood flow from the artery into the vein. A permacath is a tube inside a vein, so there is no thrill. If a fistula or graft loses its thrill, it may have clotted and needs urgent review.
AVG stands for arteriovenous graft: a soft synthetic tube placed under the skin of the arm to join an artery to a vein. The dialysis needles then go into the tube. Surgeons use it when the veins are too small or damaged for a fistula, and it is usually ready 2 to 3 weeks after surgery.
A fistula is better when your veins allow it, because it lasts longer and has fewer infections and blockages. A graft is the next choice when the veins are not suitable, and it is ready sooner.
No. The tube in the chest is a permacath, a tunnelled catheter in a large vein. A fistula, however, is a joint between your own artery and vein, usually in the arm. People sometimes call the chest catheter a “chest fistula”, but a fistula is the better long-term option.
Yes. Dialysis can start through a permacath while the surgeon makes a fistula or graft, and patients who cannot have a fistula can use a graft. Also, peritoneal dialysis, done through a tube in the abdomen, needs no fistula at all.
A well-planned access means smoother dialysis, fewer hospital stays and a better quality of life. If you or someone in your family is preparing for dialysis, see a vascular surgeon early. We will help you plan it safely, with the best long-term results in mind.
