Ileoanal Anastomosis - Types, Procedures, and Complications.

Introduction

Ileoanal anastomosis, also known as J pouch or internal pouch, refers to the connection between the ileum (terminal part of the small intestine) and the anus (terminal part of the large intestine). The large intestine is removed when there is any disease, injury, or infection. In such a situation, to restore the continuity between the intestine and the anus, an ileoanal anastomosis is created for the excreta (stool) to pass through it. It is an optional surgery after removing the colon (intestine). After a proper healing period, the procedure is reversed to resume normal colon functioning.

What Is Ileoanal Anastomosis?

Anastomosis refers to the joining of two different parts. Ileoanal anastomosis is a temporary pathway created as an alternative to storing the waste excreted from the body instead of the colon (large intestine).

Who Needs an Ileoanal Anastomosis?

The procedure of removing the colon (intestine) and the anastomosis created after that is called proctocolectomy. The conditions which require this procedure are:

• Inflammatory bowel diseases like Crohn’s disease and ulcerative colitis cause inflammation of the digestive tract.

• Familial adenomatous polyps, where polyps (extra tissue) are present in the intestine.

• Toxic megacolon (a severe complication of colon disease and infection).

• Cancers involving the colon and the rectum (terminal portion of the intestine).

When Is an Ileoanal Anastomosis Not Recommended?

The conditions wherein the procedure of ileoanal anastomosis is not recommended include

• When the small intestine is affected by a disease.

• When the anal canal is affected by an infection.

• Elderly patients as they have a greater risk for complications after surgery.

In elderly patients, it is mostly not recommended. But, some studies show a successful operation for even older patients, provided the risk of dehydration and electrolyte loss is kept in mind.

How to Prepare a Patient for Surgery?

• First, a written consent form is obtained from the patient.

• Antibiotics are given to the patient one hour before the surgery to prevent infections.

• Patients under any medication like blood thinners (Aspirin) are advised to stop them one week before surgery with the physician’s consent.

• The patient is advised not to have food the night before surgery and to have only water in the morning.

• Allergies to anesthesia or medications are informed to the doctor to prevent complications.

How to Perform Ileoanal Anastomosis Surgery?

The steps involved in the surgical procedure are:

• General anesthesia is given to make the patient unconscious and to reduce pain.

• The procedure is done by laparoscopy (a fiber-optic instrument with a camera attached at one end) or laparotomy (larger incisions or cuts are used here).

• First, small incisions are given, and the colon is located and mobilized.

• The colon and the rectum portions are removed carefully without damaging the adjacent structures.

The surgical procedure is usually done in two or three-step procedures.

1. Two-Step Procedure

• It is done when the surgery is not an emergency.

• In the first step, after removing the colon and the rectum, an ileostomy bag (a bag used to collect the waste) is placed temporarily until the ileal pouch is healed fully.

• The second step involves the reversal operation to remove the ileostomy bag.

2. Three-Step Procedure

• This procedure is done in emergencies such as toxic megacolons.

• The first step involves the removal of the colon and the rectum.

• The second step is the placement of the ileostomy bag.

• The third step is the reversal of ileostomy to remove the bag and start functioning with the ileal pouch as the reservoir of waste products from the body.

What Are the Different Types of Ileal Pouches Available?

There are three types of ileal pouches available:

1. J-Pouch

• It consists of two 15 to 20 centimeters portions of the small intestine.

• The two pouches are connected in a ‘J-shaped’ form.

• Two or three operations are performed to create the J-pouch.

• An ileostomy bag (to collect the waste products) is used temporarily until the pouch is fully healed and ready to function.

• After the pouch is healed, the stool is collected within the pouch, which is later defecated.

• It is one of the most commonly used pouches by patients.

• More preferred in diseases like inflammatory bowel disease, polyps, and cancer, where medications do not control the symptoms

2. S-Pouch

• It consists of three 15 centimeters portions of the small intestine and an extra 2 centimeters exit at the bottom.

• In some patients, the extra 2 centimeters causes difficulty clearing the stool out of the body. So, the advanced S-pouch has removed the 2 centimeters exit to ease the evacuation of stool.

• The S-pouch is preferred when the J-pouch cannot reach the anus.

• It is also used when complications arise with the use of previous pouches.

• Two or three operations are performed to create the S-pouch.

• An ileostomy bag (to collect the waste products) is used, similar to the J-pouch.

• After the pouch is healed, the stool is collected within the pouch, which is later defecated.

• This procedure is not common compared to the J-pouch.

3. K-Pouch

• It consists of three 12 centimeters portions of the small intestine and an extra 10 centimeters valve to connect with the opening made on the abdomen.

• An ileostomy bag is not required.

• The patient can decide when to evacuate the stool contents.

• The drawback with this pouch is a larger portion of the small intestine is removed compared to the J and S pouches.

What Are the Complications Associated With the Ileoanal Anastomosis Procedure?

Usually, there is only minimal discomfort for the patients with the pouches, and they get used to them with time. General complications, such as allergic reactions, pain, bleeding, swelling, and blood clot formation, can be noticed.

Specific to the surgery, short-term or long-term complications might occur.

1. Short-Term Complications

• Anastomotic leaks, wherein the contents start to leak from the pouch, can occur immediately after surgery or a few months or years later.

• Pelvic sepsis or peri pouch sepsis (a spreading infection from the vagina or cervix). This can occur when an anastomotic leak is not treated correctly.

2. Long-Term Complications

• The most common complication is pouchitis (inflammation of the ileal pouch) due to infection. The symptoms include diarrhea, abdominal cramps, anorexia (eating disorder), and urgency to defecate. Appropriate antibiotics are prescribed to treat this condition.

• Infertility (unable to get pregnant) in females.

• Obstruction of the intestine.

• Narrowing of the ileoanal anastomosis.

Conclusion

Ileoanal anastomosis is a painless surgical procedure to bypass the colon and rectum after removal. The quality of life after this surgery improves over time. The overall success rate of this procedure is excellent, but complications can also occur in some instances that can be managed easily.