Anal Fistula Plug: Complete Procedure

An anal fistula is a small, infected tunnel that forms between the skin and the anal canal. When the gland in the anal canal becomes infected, it can lead to the formation of an abscess that drains, creating the fistula. A common treatment for this condition is anal fistula plug surgery. The goal of this procedure is to close the fistula tract using a special plug, which promotes healing and prevents recurrence.

This guide will explain everything about the anal fistula plug surgery, including how it works, the steps involved, the recovery process, benefits, risks, and alternatives.

What is an Anal Fistula?

An anal fistula forms due to:

• An infection in the anal gland that develops into an abscess.
• The abscess drains on its own or after medical intervention but leaves behind a tunnel.
• If the tunnel doesn’t heal properly, it becomes a chronic anal fistula.

Symptoms of an Anal Fistula

• Pain and Discomfort: A noticeable and persistent pain around the anus, which worsens during bowel movements or when sitting for long periods.
• Drainage: Foul-smelling discharge of pus or blood from an opening near the anus.
• Swelling and Redness: Swelling or tenderness around the external opening of the fistula.
• Recurrent Abscesses: Patients often experience recurrent abscesses in the anal region, which may drain spontaneously.

What is an Anal Fistula Plug?

An anal fistula plug is a device made from biodegradable materials (such as collagen from pig intestines) designed to close the fistula tract. The plug is inserted into the fistula to fill the passage and promote healing. The plug is absorbed by the body over time, while the fistula heals naturally.

• Restores normal function: By closing the fistula, the procedure helps restore normal function of the anal canal, reducing discomfort and preventing infections.
• Promotes tissue growth: The plug acts as a scaffold for new tissue growth, allowing the body to heal the fistula from the inside out.
• Minimally invasive: The procedure is less invasive compared to traditional surgery, preserving the surrounding tissue and the anal sphincter muscle.

When is Anal Fistula Plug Surgery Recommended?

An anal fistula plug surgery is considered when the fistula is simple and straightforward, and other treatments have been ineffective. The surgery is suitable for:

• Patients with simple, low transsphincteric fistulas (those that don’t involve deep sphincter muscles).
• Patients who have failed traditional treatments, such as fistulotomies or seton placement.
• Individuals who are looking to preserve their anal sphincter muscle and avoid complications like incontinence.

Preoperative Preparation for Anal Fistula Plug Surgery

Medical Evaluation and Tests

Before undergoing anal fistula plug surgery, a thorough medical evaluation is essential. The doctor will:

• Perform a physical examination to evaluate the extent of the fistula.
• Order imaging tests, such as an MRI or an ultrasound, to determine the depth and complexity of the fistula.
• Check for any underlying conditions (such as Crohn’s disease) that may affect healing or complicate surgery.

Pre-Surgery Instructions

In preparation for the procedure, the patient will need to:

• Stop taking blood-thinning medications (like aspirin or warfarin) several days before the surgery to reduce the risk of bleeding.
• Follow a liquid diet the day before surgery, as advised by the doctor.
• Take prescribed antibiotics to prevent any infection at the surgery site.
• Undergo bowel preparation (in some cases) using an enema or other prescribed methods to clear the bowel.

Step-by-Step Procedure of Anal Fistula Plug Surgery

Unlike traditional surgeries that require cutting, this technique preserves the anal sphincter muscle, reducing the risk of complications like incontinence. The entire procedure typically takes 30-60 minutes and is performed under anaesthesia.

1. Pre-Surgical Preparation and Anaesthesia Administration

Before the surgery begins, the medical team ensures that the patient is fully prepared for the procedure. This includes:

• Patient Positioning and Preparation:
  • The patient is usually placed in a lithotomy position (lying on the back with legs elevated in stirrups) or in a prone position (lying face down).
  • The anal and perineal area is cleaned thoroughly using antiseptic solutions to reduce the risk of infection.
• Anaesthesia Administration:
  • The procedure is performed under general anaesthesia (patient is completely asleep) or spinal anaesthesia (numbness from the waist down), depending on the patient’s condition and surgeon’s preference.
  • A local anaesthetic may also be injected around the surgical site to help control postoperative pain.

2. Examination and Cleaning of the Fistula Tract

Once the patient is anaesthetised, the surgeon begins by locating and assessing the fistula tract to ensure the best approach for inserting the plug.

• Identifying the Fistula Pathway:
  • A thin, flexible probe is inserted into the external opening of the fistula to trace its pathway.
  • The probe follows the tunnel until it reaches the internal opening inside the anal canal.
  • If the fistula is complex, imaging techniques such as ultrasound or MRI may be used to get a clearer picture.
• Cleaning and Debriding the Fistula Tract:
  • The entire length of the fistula tract is irrigated with saline solution to remove any pus, debris, or bacteria.
  • If there are any infected tissues or granulation tissues (inflamed healing tissue), they are carefully removed.
  • This reduces the risk of infection and ensures a clean environment for the plug to integrate with the tissue.
• Assessing the Need for a Seton (if required):
  • In some cases, if the fistula is actively draining or infected, a seton (a thin surgical thread) may be placed a few weeks before the plug surgery to keep the fistula open and allow infection to clear.
  • If a seton is already in place, it is removed before inserting the plug.

3. Inserting the Anal Fistula Plug

Once the tract is cleaned, the anal fistula plug is inserted into the tunnel to seal it off. The plug is typically made of biodegradable porcine (pig) collagen or synthetic absorbable material.

• Sizing and Shaping the Plug:
  • The surgeon selects a plug that matches the diameter of the fistula tract to ensure a snug fit.
  • If needed, the plug may be trimmed or shaped to fit irregular or slightly wider tracts.
• Placing the Plug into the Fistula Tract:
  • The thin end of the plug is inserted first through the external opening and carefully guided through the tunnel until it reaches the internal opening inside the anal canal.
  • The plug completely fills the fistula tract, acting as a scaffold for new tissue growth.
• Securing the Plug in Place:
  • The internal end of the plug is sutured to the surrounding healthy tissue inside the anal canal.
  • These absorbable stitches hold the plug securely, preventing it from shifting or falling out.

4. Closing the External Opening (If Necessary)

After securing the plug, the surgeon decides whether to close the external opening of the fistula or leave it open for drainage.

• Leaving the External Opening Open (Preferred in Many Cases):
  • In most cases, the external opening is left open to allow any remaining fluid or infection to drain naturally.
  • The body gradually fills in the remaining space as new tissue grows around the plug.
• Partially Closing the External Opening (For Certain Patients):
  • If the surgeon determines that closing the external opening is beneficial, a few loose stitches may be placed to encourage healing while still allowing minor drainage.
  • This approach is sometimes used in smaller fistulas with minimal risk of infection.

Recovery After Anal Fistula Plug Surgery

After anal fistula plug surgery, the body begins the healing process, and the first few days are crucial. Patients should be prepared for the following postoperative effects:

• Mild to Moderate Pain:
  • Patients may feel discomfort, particularly around the anus, as the body adjusts to the newly placed plug.
  • Pain typically subsides within a few days to a week, but mild soreness can persist for up to two weeks.
  • Doctors usually prescribe pain relievers such as ibuprofen or acetaminophen to manage discomfort.
• Swelling and Inflammation:
  • It is normal to experience some degree of swelling and redness around the anal region after surgery.
  • Swelling generally peaks within 48 hours and gradually decreases over the following weeks.
  • Applying warm sitz baths (soaking the anal area in warm water for 10-15 minutes) can help reduce inflammation and promote healing.
• Drainage from the Surgical Site:
  • Some clear, yellowish, or slightly bloody discharge from the fistula opening may continue for a few days or even weeks.
  • This drainage is a normal part of the healing process and indicates that the body is naturally flushing out excess fluids.
  • Patients should use soft, absorbent pads or gauze to keep the area clean and prevent soiling of clothing.
• Bowel Movements May Be Uncomfortable:
  • The first few bowel movements after anal fistula plug surgery may be uncomfortable or slightly painful, as the surgical area is still sensitive.
  • Doctors often prescribe stool softeners or fibre supplements to prevent constipation and make bowel movements easier.
  • Drinking plenty of water (at least 8-10 glasses per day) and consuming fibre-rich foods can help ease the process.

Essential Postoperative Care Tips

Proper aftercare is crucial to ensure a smooth and successful recovery. Patients should follow these guidelines:

• Follow a High-Fibre Diet:
  • Eating fibre-rich foods such as vegetables, fruits, whole grains, and legumes helps prevent constipation and straining.
  • Straining during bowel movements can disrupt healing and potentially dislodge the anal fistula plug.
• Avoid Heavy Lifting and Strenuous Activities:
  • Activities such as lifting heavy objects, running, or engaging in intense exercise should be avoided for at least 4 to 6 weeks post-surgery.
  • Excessive strain or pressure can cause the plug to shift or delay healing.
• Take All Medications as Prescribed:
  • Patients must complete the full course of antibiotics prescribed to prevent infections.
  • If pain persists beyond the expected recovery period, patients should inform their doctor immediately.
• Keep the Anal Area Clean:
  • After each bowel movement, patients should gently clean the area with warm water or unscented baby wipes instead of harsh toilet paper.
  • Avoid using soaps with fragrances or alcohol, as they can cause irritation.
• Schedule Follow-Up Appointments:
  • Regular checkups allow the doctor to assess healing progress, ensure the plug is in place, and address any concerns.
  • The first follow-up visit is usually scheduled one to two weeks after surgery, with additional visits based on progress.

Benefits and Success Rate of Anal Fistula Plug Surgery

Anal fistula plug surgery has been shown to have a success rate of over 80%, particularly in cases where the fistula is low-risk and does not involve deep sphincter muscles. The procedure is most effective for simple fistulas and is a less invasive alternative to traditional surgeries like fistulotomy.

Minimally Invasive Nature

• Unlike fistulotomy, which involves cutting open the fistula tract, this procedure preserves healthy tissue and allows the fistula to close naturally.
• Since no major incisions are made, healing is faster, and there is less pain and scarring post-surgery.

Lower Risk of Incontinence

• Traditional fistula surgeries, especially those involving the sphincter muscles, carry a risk of faecal incontinence (loss of bowel control).
• Anal fistula plug surgery is sphincter-sparing, meaning the anal muscles remain intact, reducing the likelihood of incontinence.

Faster Recovery Time

• Most patients resume normal daily activities within 1-2 weeks post-surgery, compared to 6-8 weeks for more invasive procedures.
• Since the anal fistula plug is biodegradable, the body naturally absorbs it, and there is no need for an additional procedure to remove it.

Risks and Potential Complications

Despite its benefits, anal fistula plug surgery has some risks, including:

• Plug Failure or Fistula Recurrence:
  • The most common issue is failure of the plug to seal the fistula tract completely, leading to recurrence.
  • In such cases, patients may require a second surgery or an alternative treatment, such as fibrin glue or a seton procedure.
• Infection at the Surgical Site:
  • Any surgical procedure carries a risk of infection, which can lead to increased pain, swelling, and pus discharge.
  • Patients should monitor for signs of infection, such as persistent fever, redness, or worsening pain, and contact their doctor immediately if symptoms arise.
• Displacement of the Anal Fistula Plug:
  • In some cases, the plug may shift out of place, causing the fistula to reopen.
  • This is more likely if the fistula tract is too wide, the patient engages in strenuous activities too soon, or the healing process is slow.
• Minor Bleeding or Discharge:
  • Some patients may experience mild bleeding or prolonged drainage from the surgical site.
  • While minor discharge is normal, excessive or bright red bleeding should be reported to the doctor immediately.

When to Seek Medical Attention?

After anal fistula plug surgery, patients should contact their doctor if they experience:

• Severe pain that does not improve with medication.
• High fever (above 101°F) or chills, which could indicate an infection.
• Excessive bleeding from the surgical site that does not stop after applying gentle pressure.
• Persistent foul-smelling discharge or pus, which could signal an ongoing infection or plug failure.
• No signs of improvement within 4-6 weeks, indicating the need for further intervention.

Conclusion

Anal fistula plug surgery is a promising treatment option for patients suffering from anal fistulas. It offers a minimally invasive approach with faster recovery times and a reduced risk of complications compared to traditional surgeries. 

With a high success rate, especially in simple fistulas, this procedure has become a popular choice for many individuals looking to avoid the risk of incontinence. If you are considering anal fistula plug surgery, consult with your doctor to discuss whether it is the right option for your specific condition.