An ileostomy is a surgical procedure where the small intestine is detached from the large intestine. During surgery there is removal of either total colon and rectum or a section of small intestine. The ileostomy could be temporary if rectum and a portion of colon are preserved. Otherwise the ileostomy is permanent.
There are two types of ileostomies: conventional and continent. The conventional or Brooke ileostomy consists in taking the terminal part of the small intestine that stays connected to the stomach and adhering it to an opening on the abdominal cavity. At that point all indigested intake waste is secreted through that opening, called the stoma. In an ileostomy there is loss of sphincter, the nerves that control feces evacuation through the anus. In a conventional ileostomy, a bag has to be used to collect all the indigested body waste. The section of the ileum that is left, together with the colon and rectum are usually extracted.
In a continent Ileostomy (known as a Barnett Continent Intestinal Reservoir or BCIR), an internal pouch and a valve are created from the lower end of the ileum (the small intestine). A stoma still protrudes outside of the abdominal cavity, but only mucus flows out of it. Feces is released 2-5 times daily through a tube that is inserted in the valve. This is a painless exercise that spares the patient the permanent use of an ileostomy bag. The stoma may be covered with just a Band-Aid to contain and absorb any mucus.
There is still another option to conventional ileostomy. It is called the ileoanal pouch, also referred to as a J-pouch, ileo-anal pouch, restorative proctocolectomy, pullthrough, and IPAA (ileal pouch anal anastomosis). This procedure requires resection of the colon and the upper portion of the rectum. It must preserve the anal canal and the sphincter so that the patient can resume normal bathroom routines. The colon is replaced with an internal pouch done with small intestine tissue and stitched on the partially empty rectum space (the perineum). A pouch is fashioned from the small intestine and sutured to the lower rectum. With this operation people get to go the bathroom in the normal way, without any supplies or tubes. A good result involves having a bowel movement 4-7 times a day, and being able to delay evacuation up to 45 minutes from first feeling the urge. Problems with this operation include incontinence (stool or gas escape without intending it to happen), very frequent bowel movements, or symptoms from the remaining lower rectum. If a patient with an ileoanal J-pouch has a poor outcome, they have the option of converting to a Continent Ileostomy or a conventional ileostomy. It is not all that clear whether Crohn’s disease patients are good prospects for this procedure as there is the risk of the problem spreading to the pouch (pouchitis). Accordingly, an ileostomy is usually the better alternative.
An ileostomy may be temporary or permanent. Temporary ileostomies often occur after partial colon dissection. Once the remaining colon heals the connection can be restored. Permanent ileostomies are used to deal with chronic ulcerative colitis, bowel obstructions, colon cancer, rectal cancer, Crohn’s disease, congenital conditions, or trauma.