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Information and consent for arteriovenous fistula operation

Patient information A-Z

What is an arteriovenous fistula (AVF)?

An arteriovenous fistula is surgically created by joining an artery to a vein. It is most commonly sited on an arm but sometimes on a leg if there are no suitable vessels in the arms. Very rarely, a synthetic graft may be used to create the fistula. Once an arteriovenous fistula is created, the arterial pressure will cause dilatation of the vein. The vein will become bigger and stronger over the next few weeks and will allow cannulation for haemodialysis.

Haemodialysis is a treatment to filter wastes and water from your blood, as your kidneys did when they were healthy. To get your blood into the dialyzer, the doctor needs to make an access, or entrance, into your blood vessels.

Before your procedure

You will be admitted to either the day surgery unit on ward L2 or an inpatient ward before your procedure when you will meet the surgeon.

You will be asked if you are taking any tablets or other types of medication - these might be ones prescribed by a doctor or bought over the counter in a pharmacy or health food shop. It helps us if you bring details with you of anything you are taking (for example: bring your repeat prescription or the packaging with you).

It is important to tell us if you are on any anticoagulants (medications to prevent blood clots), for example aspirin, clopidogrel, dipyridamole, heparin or warfarin. If you are not taking an anticoagulant, you will be started on aspirin a week before your scheduled operation unless it is contraindicated. Some patients may encounter gastrointestinal ulcerations and upset stomach which needs to be reported to your doctor.

If you are on warfarin, you need to stop it five days before your operation and may need an alternative anticoagulant during this period, unless told otherwise. This will have been discussed with you in the vascular access clinic.

While you are on the ward or in the operating theatre, your surgeon might carry out an ultrasound examination to assess your arteries and veins before the procedure. The majority of people who have this type of procedure will have local anaesthesia. Occasionally sedation, regional or general anaesthesia may be used. See the section entitled ‘Your anaesthesia’ on page six for details about the types of anaesthesia / sedation we use.

This procedure is mostly done as a day case. If you are having a general anaesthetic, you will be admitted as a day case and might need to stay for about three to four hours after the procedure. Your doctor will discuss this with you before you decide to have the procedure. You might need a pre-assessment clinic appointment where a nurse or anaesthetist will assess your fitness to undergo an operation under general anaesthetic.

Hair removal before an operation

Sometimes the healthcare team may need to remove hair to allow them to see or reach your skin. If the healthcare team consider it is important to remove the hair, they will do this on the day of the using an electric hair clipper, with a single-use disposable head.

Please do not shave the hair yourself, or use a razor for hair removal, as this can increase the risk of infection to the site of the operation.

If you have any questions, please ask the healthcare team who will be happy to discuss this with you.

During the operation

Before the procedure, you will be given the necessary anaesthetic and / or sedation - see below (in section ‘Your anaesthesia) for details of this and the role of the anaesthetist in your care.

At the start of your operation, you will be given injections of local anaesthetic drugs around the vein and artery that we have identified before the operation. Once your skin is numbed, we will then make an incision to explore the vein and bring it towards the artery. These will be joined together using surgical sutures (stitches). Your skin will be closed by dissolvable sutures or with the use of glue transparent dressings. No sutures will need to be removed once the wound has healed. If you are having a general anaesthetic, the procedure will be the same but you may or may not be given the injections of local anaesthetic drugs.

After the operation

Eating and drinking: After this procedure, you can eat and drink as usual if you had local anaesthetic, or when you have recovered from the general anaesthetic or sedation.

Getting around and about: After this procedure, we will try to get you mobile (up and about) as soon as we can to help prevent complications from lying in bed. Typically, you will be able to get up after an hour once you have recovered from the anaesthesia or sedation.

Leaving the hospital: Most people who have had this type of procedure under local anaesthesia will be able to leave the hospital after half an hour. If you have had sedation or general anaesthesia, you may need to stay for a few hours or overnight until you have fully recovered from the effect of the anaesthetic. The actual time that you stay in the hospital will depend on your general health, how quickly you recover from the procedure and your doctor's opinion.

Resuming normal activities including work: Most people who have had this procedure can resume normal activities the next day. You might need to wait a little longer before resuming more vigorous activity. When you will be ready to return to work will depend on your usual health, how fast you recover and what type of work you do. Please ask your doctor for their opinion.

Driving: We advise you not to drive on the day of and up to three days after the operation. Please inform us if you are not able to arrange your transport so that we can arrange it for you.

Special measures you need to take after the procedure: You will be given more detailed information about any special measures you need to take after the procedure. You will also be given information about things to watch out for that might be early signs of problems (such as infection).

Check-ups and results: If you have already started on haemodialysis, your fistula will be checked by the dialysis nurses in your dialysis unit. If you have not started on haemodialysis, you will be followed up by your nephrologist (kidney specialist) in the low clearance or the vascular access clinic two to three weeks after the procedure. The outpatient appointment will be sent to you in the post. If you are concerned about the outcome of the operation, please phone the contacts provided below (under information and support).

If you have had general anaesthesia or sedation

You will wake up in the recovery room after your operation. You might have an oxygen mask on your face to help you breathe. You might also wake up feeling sleepy. You may have a small plastic tube placed in one of your veins temporarily, which will be connected to a bag of fluid to give any hydration you require.

While you are in the recovery room, a nurse will check your pulse and blood pressure regularly. When you are well enough to be moved, you will be taken to the ward.

Sometimes, people feel sick after an operation, especially after a general anaesthetic, and might vomit. If you feel sick, please tell a nurse and you will be offered medicine to make you more comfortable.

Intended benefits of the procedure

The intended benefit of the procedure is to create access for haemodialysis. Please read the patient information leaflet about “Arteriovenous fistula as access for haemodialysis”. The surgeon or the specialist nurse will give this information during your clinic visit.

Who will perform my procedure?

This procedure will be performed by one of the consultants, specialist registrars or clinical fellows in transplant surgery. All of them are fully trained in performing vascular access surgery.

Alternative procedure

An alternative to having an arteriovenous fistula is to have a temporary dialysis line as hemodialysis access. A dialysis line is a plastic tube, which is inserted into one of the major veins in your neck or groin. The tip of the plastic tube is within your heart, it can be life-threatening if it gets infected. The major risks associated with a dialysis line are blockage of the line, line fractures and infection, which can be potentially severe and life threatening. We strongly do not recommend a line as access for hemodialysis.

Serious or frequently occurring risks

The risk associated with this type of procedure:

  • Very common or common risk (1 in 10 people or 1 in 100 people) Failure to mature, thrombosis in fistula, mild to moderate steal syndrome (affecting blood supply to hand distal to the fistula causing a cold sensation, cramps, pain or reduced strength), aneurysm of fistula (bulging wall of the vein), numbness of skin around the fistula.
  • Uncommon or rare risk (1 in 1,000 people or 1 in 10,000 people), Severe steal syndrome (affecting blood supply to hand distal to the fistula causing tissue loss), deep infection or bleeding from fistula requiring re-operation or ligation of fistula, major nerve damage / neuropathy (causing altered sensation including pain or impaired function of the hand).
  • Risks associated with all major operations: bleeding, infection, deep vein thrombosis (blood clots in legs), pulmonary embolism (blood clots in lungs). Your consultant will explain more about these risks.

Information and support

You might be given some additional patient information before or after the procedure, for example, leaflets that explain what to do after the procedure and what problems to look out for. If you have any questions or anxieties, please feel free to ask a member of staff including:

Clinical Nurse Specialist: Please call 01223 400182 (direct line), Monday to Friday 07:00 - 15:00.

Addenbrooke's Dialysis Unit: Please call 01223 256342, Monday to Saturday 07:00 - midnight.

Satellite Dialysis Units: Monday to Saturday 07:00 - 20:00:

If you need emergency advice at all other times, please contact the Transplant Surgeon on-call via Addenbrooke's hospital switchboard on 01223 245151.

Your anaesthesia

There are three types of anaesthesia. The type chosen by your surgeon or anaesthetist depends on the surgery you are undergoing as well as your health and fitness. Sometimes the different types of anaesthesia are used in combination. The type of anaesthesia will have been chosen by the surgeon when you were examined in the access clinic.

General anaesthesia

During general anaesthesia, you are put into a state of unconsciousness and you will be unaware of anything during the time of your operation. Your anaesthetist achieves this by giving you a combination of drugs.

Before your operation

Before your operation, your anaesthetist will visit you on the ward, although occasionally this will happen in a pre-anaesthetic assessment clinic. If you are a day case patient it may not be until just before your operation. The anaesthetist who looks after you on the day of your operation is the one who is responsible for making the final decisions about your anaesthetic. They will need to understand about your general health, any medication that you are taking and any past health problems that you have had. Your anaesthetist will want to know whether or not you are a smoker, whether you have had any abnormal reactions to any of the drugs or if you have any allergies. They will also want to know about your teeth, whether you wear dentures, have caps or a plate. Your anaesthetist needs to know all these things so that they can assess how to look after you in this vital period. Your anaesthetist may examine your heart and lungs and may also prescribe medication that you will be given shortly before your operation, the pre-medication or 'premed'.

Pre-medication is the name given to medication (drugs) given to you some hours before your operation. These drugs may be given as tablets, injections or liquids (to children). They relax you and may send you to sleep. They are not always given.

Do not worry if you do not have a pre-med, your anaesthetist has to take many factors into account in making this decision and will take account of your views on the topic if possible. Do not be worried about your anaesthetic. When your anaesthetist visits you before your operation, this is the time to ask all the questions that you may have, so that you can forget your fears and worries.

Before your operation, you will usually be changed into a gown and wheeled to the operating suite into an anaesthetic room. This is a room just outside the theatre. The anaesthetist, his or her assistant and nurses are likely to be present. An intravenous line (drip) might be inserted. Monitoring devices may be attached to you, such as a blood pressure cuff or a pulse oximeter. A pulse oximeter is usually a little red light in a small box, which is taped to your finger. It shows how much oxygen you have in your blood and is one of the vital monitors that an anaesthetist uses during your operation to ensure that you remain in the best of health.

During your operation

While you are unconscious and unaware your anaesthetist remains with you at all times. They monitor your condition and administer the right amount of anaesthetic drugs to maintain you in the correct level of unconsciousness for the period of the surgery. Your anaesthetist is constantly aware of your condition and trained to respond. Your anaesthetist will be monitoring such factors as heart rate, blood pressure, heart rhythm, body temperature and breathing. They will also constantly watch your need for fluid or blood replacement. If you have any other medical conditions, your anaesthetist will know of these from your pre-operative assessment and be able to treat them during surgery.

After your operation

After your operation, your anaesthetist will continue to monitor your condition carefully. You will probably be transferred to a recovery ward where specially trained nurses, under the direction of anaesthetists, will look after you. Your anaesthetist and the recovery nurses will ensure that all the anaesthetic effects are reversed and that you are closely monitored as you return to full consciousness. You may be given some oxygen to breathe in the recovery area and may find that intravenous drips have been inserted whilst you are unconscious in theatre and that these will be replacing fluids that you might require. You will be given medication for any pain that you might feel, and systems, such as patient controlled analgesia (PCA) may be set up to continue pain control on the ward.

You are likely to feel drowsy and sleepy at this stage. Some patients feel sick, others may have a sore throat related to the insertion of the breathing tube during surgery. During this time it is important that you relax as much as you can, breathe deeply, do not be afraid to cough, and do not hesitate to ask the nursing staff for any pain relief, and about any queries you may have. You are likely to have hazy memories of this time and some patients experience vivid dreams. Once you are fully awake you will be returned to the ward, and if you are a day patient will be allowed to go to the waiting area to fully recover before you are accompanied home. Do not expect to feel completely normal immediately!

What are the risks of general anaesthesia?

In modern anaesthesia, serious problems are uncommon. Risks cannot be removed completely, but modern equipment, training and drugs have made it a much safer procedure in recent years. The risk to you as an individual will depend on whether you have any other illness, personal factors (such as smoking or being overweight) or surgery which is complicated, long or done in an emergency. Please discuss any pre-existing medical condition with your anaesthetist.

Very common and common side effects (1 in 10 or 1 in 100 people) Feeling sick and vomiting after surgery, sore throat, dizziness, blurred vision, headache, itching, aches, pains and backache, pain during injection of drugs, bruising and soreness, confusion or memory loss.

Uncommon side effects and complications (1 in 1,000 people) Chest infection, bladder problems, muscle pains, slow breathing (depressed respiration), damage to teeth, lips or tongue, an existing medical condition getting worse, awareness (becoming conscious during your operation).

Rare or very rare complications (1 in 10,000 or 1 in 100,000) Damage to the eyes, serious allergy to drugs, nerve damage, death, equipment failure.

Local anaesthesia

Many operations these days are carried out as day cases. This means you will come into hospital on the day of the operation, often only a short time before it is due to start. There are two theatre slots in the morning, we normally ask the two patients to arrive at 07:30 in day surgery unit. Whoever arrives first will be taken first to the theatre, the second patient will be asked to wait until 09:30 at the earliest. If you are listed in the afternoon, there are two slots. We will ask you to arrive at 11:30 and the first patient who arrives will be taken first to the operating theatre at around 13:00. The second patient will be taken around 15:00. Sometimes, there are unavoidable delays in the operations, so these times are approximate.

Take all your normal drugs on the day of the operation. It is OK to have food (not too much) and take a sip of water to wash any tablets down.

We have a clinic called the “one-stop service clinic” where you will be asked to come to the day surgery unit. One of the surgeons will meet you, perform an ultrasound scan and you will have your operation on the same day. The one-stop service clinic will be explained to you by a clinical nurse specialist, kidney doctor or your surgeon.

Most day-case operations are more minor, and usually do not require major pain killers afterwards. However, you may need tablets, and it is important that you have some sort of painkillers at home. If you do not, we will give you a supply to take with you.

Sometimes patients do have quite a bit of pain after day case operations and may feel sick. Do not expect to feel normal straight away, and do not plan anything important for the evening after your day case operation. Occasionally the pain or sickness is severe enough for you to be kept in hospital, though that is unusual.

Regional anaesthesia

For regional anaesthesia, a local anaesthetic drug is injected around a bundle of nerves so that a part of the body, such as an arm or a leg, is made numb. At the same time, whilst the drug is acting, the muscles in the limb are paralysed so that the limb becomes floppy. You will still be awake and know that the operation is taking place, but often the anaesthetist will administer a sedative drug so that you drift off to sleep during the operation. Even if this is not the case, you will not be able to see the operation because a screen will be placed in the way.

Examples of regional anaesthesia are the use of an epidural for pain relief during childbirth, a spinal for an operation on the bladder, and an eye block for cataract surgery. Sometimes regional and general anaesthesia are combined, particularly for major surgery, to provide pain relief after the operation.

Just as for general anaesthesia, your anaesthetist remains with you throughout the operation under regional anaesthesia, monitoring and controlling your anaesthetic state throughout in the same way. Similarly, you will go to the recovery ward afterwards until you are stable and safe to go back to the ward.


Sedation is the use of small amounts of anaesthetic or similar drugs to produce a ‘sleepylike’ state. It makes you physically and mentally relaxed during an investigation or procedure which may be unpleasant or painful (such as an endoscopy) but where your cooperation is needed.

You may remember a little about what happened but often you will remember nothing. This is known as ‘conscious sedation’ and may be used by other professionals as well as anaesthetists.

References / Sources of evidence

NICE clinical guideline No 74: Surgical site infection (October 2008); Department of Health: High Impact Intervention No 4: Care bundle to preventing surgical site infection (August 2007).

Privacy & Dignity

Same-sex bays and bathrooms are offered in all wards except critical care and theatre recovery areas where the use of high-tech equipment and/or specialist one to one care is required.

We are smoke-free

Smoking is not allowed anywhere on the hospital campus. For advice and support in quitting, contact your GP or the free NHS stop smoking helpline on 0800 169 0 169.

Other formats

Help accessing this information in other formats is available. To find out more about the services we provide, please visit our patient information help page (see link below) or telephone 01223 256998.

Contact us

Cambridge University Hospitals
NHS Foundation Trust
Hills Road, Cambridge

Telephone +44 (0)1223 245151