Encyclopedia of Health and Medicine

I–K
icterus
See JAUNDICE.
ileoanal reservoir An operation to connect the
ILEUM, the final segment of the SMALL INTESTINE,
directly with the anal canal (a short tract immediately
before the ANUS) as an alternative to
ILEOSTOMY when it is necessary to remove the
entire COLON. The surgery may take place in one
OPERATION or, more commonly, in two operations.
First the surgeon removes the colon, leaving the
anal canal, anus, and surrounding muscles intact.
Then the surgeon uses the last 18 to 20 inches of
the ileum to structure a pouch that replaces the
RECTUM, and attaches it to the anal canal. The front
end of the ileum remains as part of the small
intestine. To allow these changes to heal the surgeon
creates a temporary ileostomy, cutting the
ileum and bringing the open end through an
opening (stoma) in the abdominal wall. The
ileostomy allows digestive waste, which, coming
from the small intestine is fairly watery, to empty
outside the body. When the ileoanal reservoir has
healed, the surgeon performs a second operation
to reconnect the ends of the ileum within the
abdominal cavity and close the ileostomy.
With ileoanal reservoir the person retains control
of the anal sphincter and has bowel movements,
though stools are soft and bowel
movements more frequent (7 to 10 per day).
Bulking agents such as methylcellulose (Citrucel)
or psyllium (Metamucil) help to solidify the stool.
Foods that add bulk to the stool include bananas
and rice. Risks of ileoanal reservoir include
chronic INFECTION of the pouch, FECAL INCONTINENCE
and stool leakage, and the need to make dietary
changes (such as cutting out CAFFEINE and milk,
which often cause diarrhea). Most people who
undergo ileoanal reservoir surgery return to a satisfactory
QUALITY OF LIFE.
See also COLOSTOMY; FAMILIAL ADENOMATOUS POLY-
POSIS; INFLAMMATORY BOWEL DISEASE (IBD).
ileostomy An OPERATION in which the surgeon
brings the end of the ILEUM, the final segment of
the SMALL INTESTINE, through the abdominal wall to
exit outside the body. A pouch fastens with adhesive
to the SKIN around the ileostomal opening, or
stoma, to collect digestive waste. The waste is significantly
more watery than stool.
An ileostomy is necessary after total bowel
resection (removal of the COLON and RECTUM) such
as to treat COLON CANCER, and may be temporary or
permanent. An ileostomy is temporary when the
surgeon can construct an ileoanal reservoir and
permanent when this is not a viable option. A variation
on an ileostomy that eliminates the need for
ostomy bags is the continent ileostomy, in which
the surgeon creates a collection pouch from a section
of the ileum that remains inside the abdominal
cavity. The surgeon sutures a valve in place that
exits through the stoma. Periodically the person
opens the valve to allow digestive waste to exit.
Many people find the adjustment to an
ileostomy challenging. It represents a significant
change to the body’s appearance and function. The
ileostomy, however, need not interfere with the
regular activities of life including athletic pursuits,
job and career, and sexual activity. An ostomy-care
specialist, usually a registered nurse, will provide
education about caring for the ileostomy.
See also COLOSTOMY.
ileum The third, final, and longest segment of
the SMALL INTESTINE. About 10 feet in length, the
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