Information about your haemodialysis fistula or graft access: Fistula or graft formation for dialysis
Before the operation
This leaflet tells you about the operation to make a fistula for haemodialysis treatment and how to protect your fistula/graft after surgery. Please read it carefully as well as discussing this with your surgeon/nurse/doctor.
What is a fistula or graft?
For haemodialysis treatment to work, there needs to be a way of taking blood from you and returning it to you after it has been “cleaned” by the kidney machine. The best way to achieve this is through dialysis fistula or graft. Another less efficient way of doing this is via a dialysis line. This is because the plastic of the line can irritate the walls of the vein it sits in causing narrowings or that blood clots can form on or around the line, in both instances leading to poor flows.
Also as the line is plastic and one end of it is outside of the body and the other end sits in the vein next to the heart, there is a higher risk of infections.
If there are narrowings, clots or infections, the line will need to be removed and a new line inserted.
To make a fistula, a vein in your arm is joined to one of the arteries so that some of the blood, which usually goes to the hand, is diverted up the vein, almost like a “short circuit”. This makes the vein become larger during the following few weeks because of the increased blood flow.
It is important that the veins used for this operation are kept healthy, so please ensure that you do not have blood taken from either the wrist or elbow joint of your non-dominant arm.
E.g. If you are right-handed, protect your left arm. If you are left-handed, protect your right arm.
A graft can be inserted by a surgeon under the skin and it joins an artery to a vein to create the ‘short circuit.’ It is good as it is already at the size we need to use it and so can be used two to three weeks after insertion. Some can be used sooner than this.
Why do you need to have a fistula made?
A fistula operation is done because haemodialysis treatment is going to be needed long-term. Once the fistula has become large enough, you can be connected to the dialysis machine by putting two needles (one to remove blood and the other to return blood) into this big vein instead of using a dialysis line.
Where is the operation done?
The operation is usually done in an operating theatre and takes about 1 hour. The operation may be done using a local anaesthetic, a regional anaesthetic (or “nerve block”) or sometimes a general anaesthetic is needed. You will be sent a letter confirming your appointment for surgery and instructions about your hospital admission.
If you are having a local anaesthetic, you will be admitted to the surgical day case unit on the day of your operation.
You will be able to eat and drink as normal. If you are on the morning list, you need to arrive by 7.30am, if you are on the afternoon list, by 12.30pm and if you are on the evening list by 3pm. You will not be able to drive yourself and should make arrangements for a relation or friend to accompany you. If this will be too difficult to arrange, please ring the renal access waiting list coordinator to make alternative arrangements (number on back page). If you are having a general anaesthetic, it may be necessary to admit you to hospital for up to two nights.
For some patients who cannot tolerate a general anaesthetic an arm block is used where the anaesthetist inserts local anaesthetic into the large nerve at the shoulder to deaden the whole arm.
If you require a general anaesthetic or arm block this will be discussed at the Pre-Operative Assessment Clinic prior to surgery.
How is it done?
You will be asked to avoid eating or drinking for approximately six hours before the procedure if it is being performed with a regional or general anaesthetic (and possibly if it is being done with a local anaesthetic). When anaesthetised the skin over the wrist or elbow will be cleaned with antiseptic. A cut is made into the skin; the size of cut depends on the type of fistula or graft operation. Once the artery and vein have been found, they are sewn together. Lastly the skin is sewn back together again.
After the operation, your arm is likely to be swollen and sore for a few days. It is advisable to arrange for a relation, friend or neighbour to help you with normal daily activities, such as shopping, cooking and lifting for a few days after the operation. If this is not possible, please tell the Renal Access Specialist Nurse before you have the operation.
- The simple and most common type of fistula, a radiocephalic fistula or RCF, is made at the wrist by joining the radial artery and the cephalic vein (see diagram). The fistula remains under the skin.
- At the elbow a fistula can be made by joining the brachial artery to the cephalic vein, usually under local anaesthetic. This is called a brachio-cephalic fistula or BCF.
- Another deeper vein called the basilic vein can be joined to the brachial artery to form a fistula.
This can be done in two ways:
- In one operation: this is called a basilic vein transposition or BVT, and may be done under a regional or general anaesthetic, as the surgeons have to move the basilic vein from its deep position to a position closer to the skin and join it to the brachial artery.
- In two operations: the first operation, called a brachiobasilic fistula, joins the brachial artery to the basilic artery and the basilic vein, and is usually done under local anaesthetic. If this first operation has been successful, it will be followed a few weeks later by a larger operation called a second-stage basilic vein transposition (BVT), under a regional or general anaesthetic, to move the vein from its deep position to one that is closer to the surface of the skin.
Both of these operations using the basilic vein leave a long scar from elbow to armpit.
Some other blood vessels can be used to form fistulas, depending on individual anatomy, and what the surgeons find at the time of surgery. In some cases, you may be expecting to have one type of fistula but as a result of what the surgeons find, they may decide to do another type of access operation.
The fistula will take two to twelve weeks to strengthen and mature before it is ready to use.
Sometimes these vessels are too small to successfully make this type of fistula, so the larger vessels higher up the arm may be used instead. Occasionally, if there are no suitable veins, a plastic tube called a graft is used. This tube joins the artery and vein together to form a bridge and this is where the dialysis needles are inserted. The graft remains under the skin. Grafts are most commonly placed as a loop graft in the forearm, a straight graft in the upper arm or as a loop graft in the thigh.
You will be given an outpatient appointment for two weeks after your operation to see the Renal Access Specialist Nurse. This is to check that your fistula/graft is working and that you are recovering well, and may include an ultrasound scan of your fistula/graft.
What are the benefits of having a fistula/graft operation?
Once the fistula vein has grown in size, it can be used to connect you to the dialysis machine. A graft may in exceptional circumstances be used immediately. However, we prefer to leave them to settle for a minimum of 2 weeks before using them. In the long term you will be less likely to develop problems such as infection or clotting than if you have a dialysis line.
What are the alternatives to a fistula/graft operation?
It is possible to use a dialysis line in the long term for dialysis but this is more likely to cause complications such as infection, clotting or damage to your veins.
If you agree to have a fistula operation, you will be asked to sign the hospital’s consent form which will also state that you have received information about the procedure and have discussed it with your surgeon/nurse/doctor.
After the operation
What happens afterwards?
After the anaesthetic has worn off, you may feel some pain where the skin was cut and you may need to take a mild painkiller. There may also be some swelling of the arm for a few days. You will also have the fistula arm padded to keep it warm, and this must be kept in place until the following day.
An important indication that the fistula is working is a slight vibrating/buzzing sensation at the scar, and the vein should start to be more visible under the skin. It is VITAL that, from the day of the operation, you check that this vibrating/buzzing is present twice a day.
Most sutures are dissolvable. If non-dissolvable sutures are used the surgeons will inform you at the time when they should be removed.
Fistulas/grafts may not work first time or they may need ‘revisions’ or ‘angioplasties’ to get them working properly before we can use them for dialysis. These extra procedures may be required for the long term survival of the fistula/graft.
What are the risks of a fistula/graft operation?
With any medical procedure there is a risk of complications and it is important that you know what these are. Fistula operations have a small risk of complications.
It is important that you tell the staff beforehand if you have a problem with easy bleeding or if you are taking tablets that affect bleeding such as WARFARIN or CLOPIDOGREL or any other medication that ‘thins’ the blood. We have deliberately not included the full list of medications here as our guidance changes with time; more individual specific instructions should be sent to you in the letter we send to you.
You should also tell the staff if you are allergic to any substance, for example IODINE or LATEX.
There is also a small risk of complications from a general or regional anaesthetic should you require one for the operation.
Things to look out for
The fistula/graft does not work
The most common problem is that the blood going through the fistula clots. Usually this happens shortly after the operation, but it can occur at any time. Around one-third of fistulae do not mature enough for us to use This is more common in people with small veins. You may be given tablets to thin the blood, such as ASPIRIN, to try to prevent this happening. We may also need to do more than one procedure to get a working fistula.
A sign that the fistula is not working can be an absence of the buzzing sensation. Sometimes people cannot feel this to begin with, but it should get stronger over time. If you think the fistula is not working, please contact the Renal Unit immediately (number on back page).
There is a small risk of bleeding after the operation, and it is important that you tell the staff beforehand if you have a problem with easy bleeding or if you are taking tablets that affect bleeding such as WARFARIN and CLOPIDOGREL It is normal to have a small amount of bleeding at the wound site, but if there is a lot of bleeding, see instructions on the inside back page.
Infiltration / Blow
Sometimes when the AVF / AVG is needled blood can leak out of the vessel & into the surrounding tissue. This can occur if the arm or leg with the AVF / AVG is moved when the needles are in place. Initially some swelling occurs & later bruising develops. This is best discussed with your dialysis nurse if this occurs.
Sometimes after the needles are removed the time it takes for the blood to completely stop increases. This could be due to anatomical narrowings / stenoses or skin thinning. This needs further investigation. You or your dialysis nurse should contact the Renal Access Team.
Scab or Wound
Sometimes a scab or wound develops which does not heal between dialysis sessions. Advise from a senior dialysis nurse should be sought or the Renal Access Team (contact details on back page).
Some patients develop reactions to the cleaning agent used prior to needling or the tapes or plasters used. This can be discussed with your dialysis nurses.
After the fistula operation, there is a small risk that the wound could become infected; this can usually be prevented by keeping the area as clean as possible. If infection does occur, there will be a hot, red area over the wound site, which may be sore. This may need treatment with antibiotics. Sometimes the infection may be more serious and infect the whole fistula/graft. Please contact your GP or the Renal Unit if you suspect this.
Occasionally, most of the blood in the arm flows through the fistula/graft and not enough goes to the hand. This may make the hand feel colder than usual. In addition, you may feel pins and needles or an aching pain in the hand. Sometimes the symptoms are mild and may settle down, but if they are more severe, you will need further surgery on the fistula/graft. If you experience pain or numbness that you cannot relieve with painkillers or gentle rubbing of the hand, please contact the Renal Unit immediately.
This “steal syndrome” does not always start at the time of surgery and may come on a couple of days later. It is slightly more common in patients with diabetes.
Occasionally, the nerves that travel alongside the veins and arteries that are used to form fistulae and grafts are damaged. Mostly this will lead to areas of skin numbness that may resolve over time but sometimes does not. Very occasionally more serious problems occur with nerve damage that may require further surgery on the fistula/graft.
Aneurysm and high flow
Overtime the fistula or graft can develop swollen lumps, this is usually due to a combination of repeated needling in the same area or anatomical narrowings (stenoses).
If these lumps become too large they may need surgical procedures to reduce the size of them or to tie that section off and replace with a new section of vein or graft.
We may also need to do this if the overall flow through the fistula is too high. These examples usually occur a long time after the original operation has occurred.
Poor flow and thrombosis
Sometimes the flow in your AVF / AVG can slow down or even stop working and clot. This needs prompt investigation if we are to restore adequate blood flow, please contact the Renal Unit or Renal Access Team as soon as possible.
How can I protect my fistula/graft and reduce the risks?
It is important for you to guard and protect your fistula/graft all the time – it is the vital link between you and the kidney dialysis machine, and is regarded as a kidney patient’s “life line”.
Following the operation there are some easy steps to follow:
- You will have a clear plaster dressing to allow the wound to be seen. If there is any bleeding or infection it can then be easily detected.
- Do not cover it with restrictive clothing eg. elastic cuffs, watchbands or bandaging, tight sleeves, sweat bands or tubigrip, and do not rest handbags, shopping, heavy objects over the fistula/graft or sleep on the arm.
- The fistula/graft site needs to be checked at least twice a day to ensure it is still working and there are no problems such as infection or bleeding. If there is any doubt about the fistula/graft working, contact the Renal Unit for advice.
- Exercise the hand by clenching and unclenching the fist. This will help to develop the blood vessels. This exercise needs to be carried out twice a day for 10 minutes.
- Keep the arm warm. In cold weather, wear extra longsleeved clothing and gloves when outdoors.
- Avoid knocking the wound and be particularly careful during manual work when the arm is exposed.
- If an accident occurs that causes bleeding, apply firm pressure and elevate the arm. If the bleeding does not stop easily with firm pressure or is bleeding profusely, follow the instructions on the inside back page.
- Avoid becoming dehydrated. This can occur in hot weather or during any illness causing diarrhoea and vomiting. Dehydration can cause the fistula/graft to stop working.
- Always inform members of the medical profession that you have a fistula/graft to prevent them using your fistula/graft arm inappropriately.
- Your fistula/graft should only be used for dialysis, unless specified by the renal team.
- Never allow blood pressure to be measured on your fistula/graft arm as this will interrupt the blood flow to your arm and may cause your fistula/graft to stop working.
- Once the wound has healed, you should wash the fistula/ graft every day, and especially before dialysis, using soap and water.
- Do not scratch or pick at your fistula or graft.
- Driving can usually be resumed when you feel comfortable enough to be able to safely control your vehicle and stop in an emergency. You will need to inform your insurance company and possibly the DVLA (see the DVLA website) that you have a dialysis fistula.
- You may return to work when you feel comfortable to do the tasks required. In some cases, a more detailed assessment may need to be performed by your employer; this should be discussed with your employer.
- You may return to recreational activities once the wound has fully healed and when you feel comfortable to do so. Some activities have a higher risk of damaging your fistula/graft; please discuss this with the surgeon at the time of your surgery or with a member of the renal team afterwards.
Bleeding emergency from fistula or graft
Occasionally a fistula may bleed a little after the plaster is removed at home, if this happens it should stop quickly when pressure is applied.
However although it is a very rare occurance you should be aware of the actions to take if profuse bleeding occurs from a fistula or graft site unexpectedly between dialysis sessions.
This is a medical emergency.
- Seek help urgently from anyone who is around. The blood flow can be fast and make you feel faint so do not delay in alerting others.
- Dial 999 and report “excessive bleeding from a dialysis fistula”.
- Apply firm pressure over the bleeding site, if available use gauze and two fingers, or a large plastic bottle top or similar can help localise pressure over the bleeding site.
- Do not use too large a dressing: For example a towel may stop you applying enough pressure in the right place.
- If the bleeding is not controlled by you pressing on it then lay down and ask someone to help by supporting your arm over your head. Check you are pressing in the right place.
- Stay calm; Bleeding can usually be stopped with enough pressure in the right place. It may take more pressure than usual if the bleeding is not easily controlled.
If bleeding stops before help arrives it is important that your fistula is still checked urgently as bleeding should not happen between dialysis sessions. You should attend hospital so your fistula can be checked by a fistula surgeon. Also tell your unit.
Please be aware this is a rare occurance but it important that you and your family know how to act if it should occur. Being aware of signs of complications and reporting these promptly should ensure you do not experience a bleeding emergency.
If profuse bleeding occurs apply firm pressure, if easily available use gauze or a large plastic bottle top, see instructions on next page.
The Renal Association and the British Transplantation Society (2005) Renal Association/British Transplantation Society Standardised Patient Information Sheet. Making a fistula for haemodialysis: www.renal.org/Libraries/Procedures_for_
Patients/Formation_of_an_arteriovenous_fistula_AVF.sflb.ashx: www.renal.org/Clinical/GuidelinesSection/VascularAccess. aspx
Department of Health (2004) National Service Framework for Renal Services Part 1, Chapter 2, Standard 3. Markers of Good Practice, page 17, updated July 2006.
Care of your fistula: www.kidney.org.uk/assets/Uploads/documents/Care-of-your-fistula-july201…
Information for Patients Arteriovenous fistula (AVF) or graft - British Renal Society: http://vo2k0qci4747qecahf07gktt-wpengine.netdna-ssl.com/wp-content/uploads/2018/08/Information-for-Patients-AVF-and-graft-BRS-Final.pdf
NHS Constitution. Information on your rights and responsibilities: www.nhs.uk/aboutnhs/constitution
How to contact us:
If you have any queries or concerns about your fistula whatsoever, or have not understood anything you have been told, please do not hesitate to ring us.
Renal Access Team
0117 414 5216
Renal Access Waiting List Coordinator
0117 414 7707
Renal Ward 8B
0117 414 4801
If you or the individual you are caring for need support reading this leaflet please ask a member of staff for advice.
© North Bristol NHS Trust. This edition published July 2019. Review due July 2021. NBT002093.