Surgery for Anal Abscess and Fistula
TREATMENT OF ANAL ABSCESS
The treatment of an abscess is surgical drainage under most circumstances. An incision is made in the skin near the anus to drain the infection. Depending on the situation, this is done in a doctor’s office with local anesthetic or in an operating room under deeper anesthesia. Hospitalization may be required for patients prone to more significant infections, such as diabetics or patients with decreased immunity, or for very complicated infections.
Up to 50% of the time after an abscess has been drained, a fistula may persist, connecting the infected anal gland to the external skin. This typically will involve some type of drainage from the external opening. If the opening on the skin heals when a fistula is present, a recurrent abscess may develop. Until the fistula is eliminated, many patients will have recurring cycles of pain, swelling and drainage, with intervening periods of apparent healing.
TREATMENT OF ANAL FISTULA
Surgery is almost always necessary to cure an anal fistula. If the fistula is simple and involving minimal sphincter muscle, a fistulotomy may be performed. This procedure involves unroofing the fistula tunnel, connecting the internal opening within the anal canal to the external opening and creating a groove that will heal from the inside out.
The surgery may be performed at the same time as drainage of an abscess, although sometimes the fistula doesn’t appear until weeks or years after the initial drainage.
Fistulotomy is a long-standing treatment with a high success rate (92-97%). This high success rate must be balanced, however, with the potential changes to a patient’s continence (ability to control stool), as the anal sphincter muscle is divided in a fistulotomy, the greater the risk of changes in continence. Therefore, the surgeon must assess whether a fistulotomy is appropriate for a given patient.
Endoanal Advancement Flap
For complex fistulas, our colorectal surgeons will often employ an endoanal advancement flap. This can be used for patients with an increased potential risk for suffering incontinence from a traditional fistulotomy. In this procedure, the internal opening of the fistula is covered over by healthy, native tissue in an attempt to close the point of origin of the fistula. Recurrence rates have been reported to be up to 50% of cases. Although the sphincter muscle is not divided in this procedure, mild to moderate incontinence remains a risk of the advancement flap.
LIFT (ligation of the interspinchteric fistula tract)
Yet another non-sphincter dividing treatment for anal fistula is the LIFT (ligation of the intersphincteric fistula tract) procedure. This procedure involves division of the fistula tract in the space between the internal and external sphincter muscles. This procedure avoids division of the sphincter muscle, but has not been performed long enough to adequately assess its success or the most appropriate cases to attempt it on.
WHAT IS THE RECOVERY LIKE FROM SURGERY?
You should expect some anorectal pain after surgery. Pain is controlled with pain medication, fiber and bulk laxatives. We will teach you how to perform sitz baths. It is important to avoid constipation that can be associated with prescription pain medication. Discuss with your surgeon the specific care and time away from work prior to surgery to prepare yourself for post-operative care.
American Society of Colorectal Surgeons