Dialysis fistula creation (AV fistula): what the operation involves and aftercare

Haemodialysis cleans the blood when the kidneys can no longer do the job. Kidney Care UK says blood is taken from the body, run through a dialysis machine filter to remove toxins and excess fluid, and then returned. To do that several times a week, the machine needs a reliable way into the bloodstream.

An arteriovenous fistula is that route. Kidney Care UK describes a small medical procedure that joins an artery, which carries blood from the heart round the body, to a vein, which carries blood back to the heart, making one large, stronger blood vessel. The NHS says the fistula is usually on the inside of the arm, on the wrist or at the elbow.

The reason for the connection is practical: the joined vessel is larger and stronger than an ordinary vein, which suits repeated use for dialysis. It needs time to mature and become strong enough before it is used.

A fistula is created for people who are expected to need haemodialysis for kidney failure. Kidney Care UK explains that once someone with chronic kidney disease starts dialysis, they will need it for the rest of their life or until they receive a kidney transplant. The kidney team usually plans ahead, so the fistula can be ready before dialysis begins.

Timing matters. The NHS says you will need the procedure around 10 weeks before starting treatment, and Kidney Care UK says about six to eight weeks to allow it to mature and become strong enough. These figures come from different organisations, and your own team will advise on the schedule that applies to you.

Not everyone is able to wait. Kidney Care UK says that if you need dialysis before your fistula or graft is ready, or if you cannot have one made, haemodialysis can be given through a special dialysis line in the neck, called a central venous line, which can be used immediately.

The NHS says the procedure to join an artery and vein is usually done under local anaesthetic and takes about an hour. A surgeon joins the two vessels, usually in the arm. Your unit will explain how long you will be there and give specific instructions for the first days afterwards.

The choice of arm and site is a clinical decision made by your kidney and surgical team, and depends on your own blood vessels and other health conditions.

Kidney Care UK also notes that you will be advised to have a vaccine against hepatitis B, a virus that can be caught from blood. It may be given by the dialysis team or your GP.

After the operation the fistula is not used straight away. Kidney Care UK says it needs six to eight weeks to mature. During this time the new vessel is left to develop and strengthen.

Your team will check whether it is developing properly by feeling for the buzz and sometimes by scanning it. Kidney Care UK says that sometimes a fistula or dialysis line may not work very well, and extra tests and procedures may be needed to improve its function.

Be aware that fistulas are not guaranteed to work. Kidney Care UK states that fistulas can stop working. That is why people who may need dialysis are usually looked after by a team that monitors the access regularly rather than leaving it until the day treatment is due.

Once the fistula is ready, it is used to connect you to the machine at each haemodialysis session. The NHS says each session takes around 4 hours and most people need 3 sessions a week, in a local hospital or dialysis unit, although some people can have equipment installed at home.

Kidney Care UK says that fistulas may bruise, especially when they are first used, and that this gets better with time. Anaesthetic cream can help relieve pain when the needle is inserted.

• Feel for the buzz, or thrill, in your fistula regularly, and know what it normally feels like.

• If the buzz disappears between dialysis sessions, call your unit immediately, as Kidney Care UK advises.

• Report any new problems with the access site to your unit rather than waiting for the next session.

• Attend every dialysis session; Kidney Care UK says this is very important so that toxins are removed regularly.

• Follow your dietitian's advice on fluids and food, and keep to medicine advice from your kidney team.

Kidney Care UK says people on dialysis may develop an infection in the bloodstream, which can be treated with antibiotics, and may have problems with the fistula or dialysis line. These are good reasons to report new symptoms early rather than waiting for the next session.

The NHS says haemodialysis can leave you feeling tired and sick, and can cause muscle cramps and dizziness during or shortly after a session. Kidney Care UK adds that low blood pressure can occur, and that reducing how much fluid needs to be removed at each session, by controlling fluid intake between sessions, can ease this.

If you feel very unwell, have heavy bleeding from the fistula site, or a high temperature with shivering, contact your dialysis unit straight away, or NHS 111, or call 999 in an emergency. Keep the unit's out-of-hours contact details somewhere you can find them quickly.

If blood vessels are very small or fragile, Kidney Care UK says a piece of tubing called an arterio-venous graft may be used instead of a fistula. A central venous line in the neck is the option when dialysis has to start before a fistula is ready, or when a fistula cannot be made.

Fistulas are only relevant to haemodialysis. The NHS describes peritoneal dialysis, in which a flexible tube called a catheter is placed into the tummy about 2 weeks before treatment so that dialysis fluid can flow in and out, usually at home and daily. Kidney Care UK lists other options for kidney failure as a kidney transplant from a donor, or conservative care, which means managing symptoms without active kidney replacement treatment. The kidney team will go through the choices with you and your family.

On the NHS, fistula creation is arranged by the kidney (renal) team as part of preparing for dialysis. It is free at the point of use, and the team monitors the access over time.

Some people also see a private vascular surgeon, usually for a second opinion or to be operated on sooner. Because access planning is closely tied to when dialysis will start and who looks after it afterwards, make sure your kidney team knows about any care you arrange elsewhere. Ask who will check the fistula and who to call if it stops buzzing.