Anal Fistula Surgery

What is an anal fistula?

An anal fistula is an abnormal connection between the anal canal and the skin around the anus.

Symptoms include: skin irritation, a constant or throbbing pain and discharge from the area around your anus. If a collection of pus has formed you may also get a high temperature, feel very tired and also feel quite unwell.

Why have I got an anal fistula?

An anal fistula is normally caused by a collection of pus (abscess) that either bursts or does not completely resolve causing a connection. However, it may also be caused by some other conditions of the bowel such as Crohn’s disease.

Reasons for having anal fistula surgery.

Unfortunately, anal fistulas rarely heal on their own and require surgical treatment. Treatments vary greatly depending on the size and site of your fistula; your surgeon will have assessed your fistula in clinic and will have decided on the best treatment for you.

Alternative treatments.

You may choose not to proceed with surgery and instead opt for antibiotic treatment only. However, it is likely that these infections will reoccur several times a year and may require surgical drainage of the pus in an emergency setting.

What does the procedure involve?

Laying open of fistula: If the fistula tract does not involve too much of the muscles (sphincters) that help keep you continent your surgeon may choose to cut open the whole tract and leave it open to heal on its own.

Seton: if your fistula involves the muscles (sphincters) that help to keep you continent your surgeon may decide to place a thin piece of rubber tape through the fistula tract and leave in place, this allows the tract to remain open to prevent recurrence of the infection. This is left in place for a number of months and as your body heals it pushes the seton to the surface without damaging your sphincters. You will then have this tape either removed at a later date.

Advancement flap procedures: if your fistula is particularly complex or there is a high risk of incontinence, your surgeon may choose to do an advancement flap. This is when the fistula tract is removed and a piece of tissue usually taken from the skin around the anus is attached in its place.

Bioprosthetic plug: is a cone-shaped plug made from animal tissue. This is used to block the internal opening of the fistula. This is then stitched into place. The other end of the fistula is left open to allow it to continue to drain. Tissue grows around the plug to allow it to heal over.

Filler: the filler is injected into the fistula tract to seal it closed. The opening of the fistula is then stitched closed.

LIFT (Ligation of Intersphincteric Fistula Tract) Procedure: your surgeon makes an incision to the side of your anus and identifies the fistula tract, they then use sutures to close off the internal tract opening near the anus. The fistula tract is then removed and any defects closed with sutures.

What about the anaesthetic?

You will receive a general anaesthetic for your surgery; you will see your anaesthetist on the day of surgery who will discuss your anaesthetic further with you.

What happens before the operation?

Prior to your admission you will have seen a member of the surgical team to discuss the surgery and its risks and benefits.

You will have a pre-operative assessment where you are likely to be examined by a practitioner, have bloods taken and be asked about your past medical history, previous surgeries and asked about any medications you may be taken. At times you may be asked to stop taking certain medications prior to surgery, these may impose an added risk to surgery such as blood thinning medications.

You will receive a letter detailing the date of your surgery, time and ward to report to for your admission. You will also be advised on what to bring to hospital with you.

Upon admission on to the ward you will be shown where to sit, where you will be see a number of different people. You will be seen by a nurse who will take some information from you and will attach patient identification bands around your wrists or ankles. You will be given a gown to wear for theatre and white stockings to wear to help prevent blood clots. You will also be seen by a member of the surgical team who will go through the consent form for your procedure with you, an anaesthetist who will discuss your anaesthetic. Please stay on the ward so that you may be seen by all these people to avoid delays in your surgery.

When your theatre team is ready for you, a member of the team will walk to the ward to collect you; they will check a few details with you and then walk you to theatre (if you are able). You will then be taken into the anaesthetic room where you will be met by your anaesthetist. A member of the theatre team will ask you to lie on a theatre bed, and will attach a blood pressure cuff to your arm; a probe onto your finger to measure your oxygen levels and three stickers attached to wires will be placed onto your chest to monitor your heart. You will also have a needle placed into a vein on the back of your hand or arm; this allows the anaesthetist to administer the medications required for your anaesthetic.

What happens after the operation?

After your surgery you will be taken into recovery where you will receive individual specialist care whilst you are waking up from the anaesthetic. When you are awake and feel ready you will be given something to eat and drink. You will be encouraged to get up and mobilise to reduce the risk of developing blood clots.

You will be prescribed stool softeners as it is very important that you do not get constipated and strain to open your bowels as this will cause you a lot of pain. You may find that you are sore following your operation; your surgeon will have prescribed painkillers for you to take to ease your discomfort.

You may have a dressing in place following surgery; your surgeon will advise you when and how often this will need redressing.

Avoid sitting in a bath, instead shower or use warm water and cotton wool to wash the skin, rather than a towel or sponge and pat the skin dry rather than rubbing it.

Discharge from hospital.

Most patients can expect to go home the same day following their surgery, on occasions it may be beneficial for you to stay in hospital overnight. Your surgeon will advise you on this.

Please ensure that you have somebody who can bring you home from hospital as you will not be able to drive. You will also need to have somebody to stay with you for 24 hours following surgery whilst you recover from the anaesthetic.

We expect you to make a rapid recovery after your operation and to experience no serious problems. However, it is important that you should know about minor problems, which are common after this operation, and also about more serious problems that can occasionally occur.

What problems can occur after the operation?

Bleeding – a small amount of bleeding is common after this type of surgery; this may last a few days. If however, the bleeding worsens or continues over a longer period of time please contact your GP

Infection – although uncommon, there is a chance that you could develop and infection in or around your wound site. This is generally treated well with antibiotics. In extreme cases you may need to come into hospital for further treatment.

Deep vein thrombosis (DVT) - Deep vein thrombosis is a possible problem, but is uncommon. If you are at particular risk then special precautions will be taken to reduce the risk. Moving your legs and feet as soon as you can after the operation and walking about early, all help to stop thrombosis occurring.

Key hole deformity – it is possible that the area of skin which contained the fistula does not return to its original state after treatment and you are left with an area indentation. This should not cause you any problems.

Faecal incontinence – although rare, there is a possibility of becoming incontinent of faeces following this type of surgery. You are at slightly higher risk of developing incontinence if your fistula involves the sphincters or if it is particularly complex. Incontinence usually improves with time but you may be permanently left with weak sphincters.

Recurrance – it is possible that despite your fistula being treated fully, you may find that you develop another one. This will need to be treated similarly to the original one.

Failure – although rare it is possible that the treatment you receive for your fistula fails to resolve, if this were to happen then your surgeon will discuss other surgical options with you.

The risks of a general anaesthetic

General anaesthetics have some risks, which may be increased if you have chronic medical conditions, but in general they are as follows:

Common temporary side effects (risk of 1 in 10 to 1 in 100) include bruising or pain in the area of injections, blurred vision and sickness, these can usually be treated and pass off quickly.

Infrequent complications (risk of 1 in 100 to 1 in 10,000) include temporary breathing difficulties, muscle pains, headaches, damage to teeth, lip or tongue, sore throat and temporary problems with speaking.

Extremely rare and serious complications (risk of less than 1 in 10,000). These include severe allergic reactions and death, brain damage, kidney and liver failure, lung damage, permanent nerve or blood vessel damage, eye injury, and damage to the voice box. These are very rare and may depend on whether you have other serious medical conditions.

What should you do if you develop problems?

If you develop problems shortly after leaving hospital please contact the ward you have been discharged from. Otherwise please contact your GP.

Do you need to return to hospital for a check?

You will be sent an appointment to attend outpatients’ clinic in 6-8 weeks following surgery.

Who should you contact in an emergency?

Please attend your local accident and emergency department or if your condition is life threatening please call for an ambulance.