Facts About Your
Colonoscopy
What
is a colonoscopy?
A colonoscopy (koh-luh-NAH-skuh-pee)
allows a doctor to look inside the entire large intestine. The procedure
enables the physician to see things such as inflamed tissue, abnormal
growths, and ulcers. It is most often used to look for early signs of cancer
in the colon and rectum. It is also used to look for causes of unexplained
changes in bowel habits and to evaluate symptoms like abdominal pain, rectal
bleeding, and weight loss.
What is the colon?
The colon, or large
bowel, is the last portion of your digestive tract, or gastrointestinal
tract. The colon is a hollow tube that starts at the end of the small
intestine and ends at the rectum and anus. The colon is about 5 feet long,
and its main function is to store unabsorbed food waste and absorb water and
other body fluids before the waste is eliminated as stool.
Preparation
You will be given
instructions in advance that will explain what you need to do to prepare for
your colonoscopy. Your colon must be completely empty for the colonoscopy to
be thorough and safe. To prepare for the procedure you will have to follow a
liquid diet for 1 to 3 days beforehand. The liquid diet should be clear and
not contain food colorings, and may include
fat-free
bouillon or broth
strained fruit
juice
water
plain coffee
plain tea
diet soda
gelatin
Thorough cleansing of the
bowel is necessary before a colonoscopy. You will likely be asked to take a
laxative the night before the procedure. In some cases you may be asked to
give yourself an enema. An enema is performed by inserting a bottle with
water and sometimes a mild soap in your anus to clean out the bowels. Be
sure to inform your doctor of any medical conditions you have or medications
you take on a regular basis such as
aspirin
arthritis
medications
blood thinners
diabetes
medication
vitamins that
contain iron
The medical staff will
also want to know if you have heart disease, lung disease, or any medical
condition that may need special attention. You must also arrange for someone
to take you home afterward, because you will not be allowed to drive after
being sedated.
Procedure
For the colonoscopy, you
will lie on your left side on the examining table. You will be given pain
medication and a moderate sedative to keep you comfortable and help you
relax during the exam. The doctor and a nurse will monitor your vital signs,
look for any signs of discomfort, and make adjustments as needed.
The doctor will then
insert a long, flexible, lighted tube into your rectum and slowly guide it
into your colon. The tube is called a colonoscope (koh-LON-oh-skope). The
scope transmits an image of the inside of the colon onto a video screen so
the doctor can carefully examine the lining of the colon. The scope bends so
the doctor can move it around the curves of your colon.
You may be asked to
change positions at times so the doctor can more easily move the scope to
better see the different parts of your colon. The scope blows air into your
colon and inflates it, which helps give the doctor a better view. Most
patients do not remember the procedure afterwards.
The doctor can remove
most abnormal growths in your colon, like a polyp, which is a growth in the
lining of the bowel. Polyps are removed using tiny tools passed through the
scope. Most polyps are not cancerous, but they could turn into cancer. Just
looking at a polyp is not enough to tell if it is cancerous. The polyps are
sent to a lab for testing. By identifying and removing polyps, a colonoscopy
likely prevents most cancers from forming.
The doctor can also
remove tissue samples to test in the lab for diseases of the colon (biopsy).
In addition, if any bleeding occurs in the colon, the doctor can pass a
laser, heater probe, electrical probe, or special medicines through the
scope to stop the bleeding. The tissue removal and treatments to stop
bleeding usually do not cause pain. In many cases, a colonoscopy allows for
accurate diagnosis and treatment of colon abnormalities without the need for
a major operation.
During the procedure you
may feel mild cramping. You can reduce the cramping by taking several slow,
deep breaths. When the doctor has finished, the colonoscope is slowly
withdrawn while the lining of your bowel is carefully examined. Bleeding and
puncture of the colon are possible but uncommon complications of a
colonoscopy.
A colonoscopy usually
takes 30 to 60 minutes. The sedative and pain medicine should keep you from
feeling much discomfort during the exam. You may feel some cramping or the
sensation of having gas after the procedure is completed, but it usually
stops within an hour. You will need to remain at the colonoscopy facility
for 1 to 2 hours so the sedative can wear off.
Rarely, some people
experience severe abdominal pain, fever, bloody bowel movements, dizziness,
or weakness afterward. If you have any of these side effects, contact your
physician immediately. Read your discharge instructions carefully.
Medications such as blood-thinners may need to be stopped for a short time
after having your colonoscopy, especially if a biopsy was performed or
polyps were removed. Full recovery by the next day is normal and expected
and you may return to your regular activities.
For More Information
American
College of Gastroenterology
P.O. Box 342260
Bethesda, MD 20827–2260
Phone: 301–263–9000
Fax: 301–263–9025
Email:
info@acg.gi.org
Internet:
www.acg.gi.org
International
Foundation for Functional Gastrointestinal Disorders
P.O. Box 170864
Milwaukee, WI 53217–8076
Phone: 1–888–964–2001 or 414–964–1799
Fax: 414–964–7176
Email:
iffgd@iffgd.org
Internet:
www.iffgd.org
National Digestive Diseases Information
Clearinghouse
2 Information Way
Bethesda, MD 20892–3570
Email:
nddic@info.niddk.nih.gov
The
National Digestive Diseases Information Clearinghouse (NDDIC) is a service
of the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK).
The NIDDK is part of the National Institutes of Health of the U.S.
Department of Health and Human Services. Established in 1980, the
Clearinghouse provides information about digestive diseases to people with
digestive disorders and to their families, health care professionals, and
the public. The NDDIC answers inquiries, develops and distributes
publications, and works closely with professional and patient organizations
and Government agencies to coordinate resources about digestive diseases.
