What is an Anal Fistula?

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A fistula is a connection between two areas of the body or organs. An anal fistula is a connection between the anus (or part of the lower rectum) to the skin externally around the anus. They usually start by an anal gland becoming infected which can result in an abscess forming. This can then start to form a channel (or fistula) between this area and the skin to naturally allow it to drain. This is why pus may intermittently discharge from a skin opening.

 

Other disease such as Crohn’s disease, trauma/injury, cancer or radiotherapy or childbirth can cause anal fistulas to form.

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The common symptoms are:

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• Small amounts of bleeding on underwear or toilet paper.

• Discharge from the back passage

• Pruritus i.e. itching around the back passage

• Pain: usually if there is a build up of pus which usually eases following discharge as pressure is released from an abscess collection.

• Other symptoms relating to a primary disease causing the problem.

 

Fistulas can start at different levels of the anal canal. Sometimes and examination under anaesthetics of=r an MRI scan will be undertaken before surgery to establish the site and tracts that are present before surgery. The higher it starts inside the back passage and if it involves more muscle, then there is an increased likelihood of requiring a seton (material thread) and more operations to minimise risks of incontinence and complications (see below).

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What do I do if I have any bleeding?

 

It is important that you see your GP or inform your specialist. Bleeding can be due to many reasons and usually requires further investigations to rule out more worrying pathology/disease.   

 

What treatment is available?

 

 

Alternatives to an Operation

 

Anal fistulas will require surgery to treat them and will not heal by themselves.

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What does an Operation Involve?

 

Sometimes your specialist may suggest an operation. This is usually done under a general anaesthesia (where you are asleep) but the best options will be discussed with the anaesthetist.

 

An examination under anaesthesia will take place to probe and identify an internal opening, external opening and any further fistula tracts that maybe present. Depending on the findings, there may be different ways of treating the fistula.

 

• If the fistula is very near the anal opening and involves very little muscle, then the fistula can be opened up and packed. This will need dressing changes to stop the skin from closing allowing the deeper layers to close first and reducing recurrence rates.

• If the fistula is higher, involves more muscles or is complex, then part of the tract can be opened and packed whilst areas involving muscle or deeper regions may have a seton inserted (material thread). This allows drainage to stop recurrent abscesses and allows the tract to become more superficial/shallower.

• If fistulas are very high or involve other organs and form pelvic collections, then a colostomy may need to be formed. This is rare and your specialist will advise of this before any operation.

• Other treatment methods include using special glues, clips, flaps to cover the internal opening and plugs made of animal tissue.

 

Before the operation you will likely be advised to have laxatives to keep your stools soft before the operation. Ensure you tell your specialist and anaesthetist about all medication you take. You will usually also have a pre-assessment appointment to ensure you are optimised before your surgery.

 

General recommendations for all operation is to reduce or stop smoking as this decreases complications of wound infections, breakdown, chest infections and longer term health problems. Regularly exercising even leading up to your operation has shown to improve on outcomes post-operatively by leading to better ‘pre-habilitation’.

 

On the day operation day.  The procedure is usually done as a day case procedure and therefore be admitted and discharged from the hospital on the same day. After the anaesthetic, you will be given local anaesthetic to help with any pain post-operatively and may be given antibiotics.

 

 

Potential Complications

 

Complications can be both general for any operation and specific for the particular procedure.

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Complications are rare but all of the potential ones are listed below.  Smaller haemorrhoids and ones amenable to THD, haemorrhoidopexy and Rafaelo Procedures have less potential complications. Your specialist will be able to go over specific ones with you.

 

General Complications:

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1. Pain: This can be very painful and can last for a few weeks. Local anaesthetic may be given after the operation then you should take regular pain killers and importantly keep your stools as soft as possible to avoid constipation. This will help with pain and aid healing.

2. Bleeding: Bleeding can happen for 1-2 weeks after the operation.

3. Infections: This usually causes a high temperature, pus from the anal passage, redness, swelling and increased pain. Antibiotics are used to treat this. It is safe to shower after 2 days following the operation.

4. Blood clots in the legs or lungs: Keeping mobile is important to prevent this along with the use of TED stockings.

5. Scarring around the perianal area.

 

Specific Complications:

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1. Limited or Staged Treatment: The operation may require a staged approached (with more then one operation) to optimally treat the fistula and avoid complications.

2. Incontinence: This can happen temporarily due to swelling from healing around the back passage area. This is usually to very liquid stool or wind and usually settles after a few weeks (risk of upto 8 in 10 people). It is extremely rare to have more longer-term incontinence from damage to anal sphincters.

3. Anal Fissure: This is a painful cut around the back passage area. If this occurs then usually this responds to medication and laxatives which your specialists can provide.

4. Difficulty passing urine: The risks of this is higher if you already have problems passing urine before the operation. If this occurs then you may require a urinary catheter and may occur in 1 in 5 people. 

 

Recovery from the Operation

 

Following the operation, you will be wake up in recovery and usually go home the same day. You will require a responsible adult to be with you at home for the first 24 hours and have access to a telephone in case you help or advice is required. It is important to continue to take regular pain killers and laxatives to avoid constipation and aid healing for several weeks. You may also be given antibiotics for 5 days following your operation.

 

Activities following surgery

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For the first 24 hours following a general anaesthetic or sedation, do not drive, operative machinery, carryout dangerous activities, drink alcohol or sign legal paperwork. You can usually start driving once you can control and make an emergency stop.  It is important to be mobile to avoid blood clots and may need to wear stockings to prevent these. Depending on the type of work you do, you can usually return within 1-2 weeks.

 

You will usually have a follow-up after you operation between 4-12 weeks depending on the operation carried out.