Imperforate anus repair

Definition

Imperforate anus repair is surgery to correct a birth defect involving the rectum and anus.

An imperforate anus defect prevents most or all stool from passing out of the rectum.

See also: Imperforate anus

Alternative Names

Anorectal malformation repair; Perineal anoplasty; Anorectal anomaly; Anorectal plasty

Description

How this surgery is performed depends on the type of imperforate anus. The procedures are done under general anesthesia, which means the infant is asleep and feels no pain during the procedure.

For mild imperforate anus defects:

• The first step involves enlarging the opening where the stool drains so stool can pass more easily.
• Surgery involves closing any small tube-like openings (fistulas), creating an anal opening, and putting the rectal pouch into the anal opening. This is called an anoplasty.
• The child must often take stool softeners for weeks to months.

Two surgeries are often needed for more severe imperforate anus defects:

• The surgeon will create an opening in the skin and muscle of the abdominal wall and attach the end of the large intestine to the opening. Stools will drain into a bag attached to the abdomen. This is called a colostomy.
• The baby is often allowed to grow for 3 - 6 months.
• For the second procedure, the surgeon may make a cut in the abdomen to detach and move the colon to a new position. A cut is made in the anal area to pull the rectal pouch down into place and create an anal opening.
• The colostomy will likely be left in place for 2 - 3 more months.

A major challenge for these repairs is finding, using, or creating nearby nerves and muscles so that the child can move the bowels normally.

Why the Procedure Is Performed

The surgery repairs the defect so that stool can move through the rectum.

Risks

Risks for any anesthesia include:

• Reactions to medications
• Problems breathing

Risks for any surgery include:

• Bleeding
• Infection

Risk specific to this procedure include:

• Damage to the urethra (tube that carries urine out of the bladder)
• Long-term problems with bowel movements because of damage to the nerves and muscles that supply the colon and rectum
• Temporary paralysis of the bowel (paralytic ileus)

After the Procedure

The infant may be able to go home later the same day after a mild defect is repaired. Or, the child may spend several days in the hospital.

The health care provider will use an instrument to dilate (stretch) the new anus to improve muscle tone and prevent narrowing. This must be continued for several months. Stool softeners and a high-fiber diet are recommended throughout childhood.

Outlook (Prognosis)

Most defects can successfully be corrected with surgery. Most children with milder defects do very well. However, constipation may be a problem.

Children who had more complex surgeries still usually have control of their bowel movements. However, they often need to follow a bowel program, including eating high-fiber foods, taking stool softeners, and sometimes using enemas.

Some children may need more surgery.

References

Klein MD, Thomas RP. Surgical conditions of the anus, rectum, and colon. In: Kliegman RM, Behrman RE, Jenson HB, Stanton BF, eds. Nelson Textbook of Pediatrics. 18th ed. Philadelphia, Pa: Saunders Elsevier;2007:chap 341.

Warner BW. Pediatric surgery. In: Townsend CM, Beauchamp RD, Eyers BM, Mattox KL, eds. Sabiston Textbook of Surgery, 18th ed. Philadelphia, Pa: Saunders Elsevier; 2007:chap 71.