The different types of ostomy surgeries are named according to the digestive and excretory organs affected. All types of ostomy surgery involve the diversion of the body’s waste products from their normal routes to an opening in the abdomen called a stoma. For example, if the surgery involves rerouting the colon, it is a colostomy. When the bladder is removed, a urostomy is performed to divert urine to one or two stoma. If the entire colon is removed or bypassed, an ileostomy is performed to allow the contents of the small intestine — the ileum — to exit through the abdominal wall.
Colostomy surgeries are named according to what part of the colon is diverted. One of the most common types of colostomy is the descending or sigmoid colostomy. This surgery bypasses only a small section of the colon and rectum. The healthy part of the colon is brought to the outside of the lower left abdomen, folded over on itself and stitched to the skin. This creates the stoma through which feces will exit the body into a collection pouch.
If the surgery is performed in the transverse section of the colon, it is referred to as a transverse colostomy. This may be a temporary ostomy, bypassing the colon so it can heal. Other transverse colostomies are permanent. In a loop transverse colostomy, two stomas are formed by bringing a loop of the colon to the surface. One stoma is for feces, the other for drainage of mucus formed in the colon.
A double-barrel transverse colostomy involves cutting the colon and creating one or two stomas. If two stomas are present, one is for the discharge of mucus from the inactive portion of the colon while the other is for feces. When only one stoma is created, any mucus from the inactive portion of the colon exits through the anus. An ascending colostomy is rarely performed. Many surgeons prefer an ileostomy if only a small section of the colon can be saved.
Ileostomy surgery routes the contents of the small intestine to a stoma in the abdomen. Standard ileostomies take the small intestine to the surface of the abdomen and turn it back on itself, forming a stoma. The waste that passes is liquid or very soft. It contains powerful digestive enzymes that should not be allowed to touch the skin. Caring for this type of ostomy involves protecting the skin from the wastes.
When the bladder is diseased or damaged, a urostomy diverts urine to a stoma in the abdomen. A standard urostomy creates a small pouch from a portion of the small intestines. The ureters — tubes from the kidneys to the bladder — flow into this pouch instead of into the bladder. The stoma where the urine exits the body is formed using a piece of the intestine. Ureterostomies are rare and involve taking the ureters directly to the surface to form the stomas.
None of the different types of ostomy surgeries have a sphincter — a muscular valve — to control the output of wastes. For this reason, a collection pouch, which is usually external, must be worn. An internal pouch is used in a continent urostomy and a continent ileostomy. In both of these types of ostomy procedures, a catheter is used several times a day to empty the internal pouch.