What is a small bowel obstruction?
A small bowel obstruction is a blockage of the small
intestine. The small intestine begins at the end of the
stomach and ends where the colon (large intestine) starts.
The blockage makes it hard for the contents of the bowel to
pass through and out of the body.
How does it occur?
The small bowel may become blocked when it is trapped inside
the abdominal cavity in scar tissue or outside the abdominal
cavity in a hernia.
- Adhesions are the major cause of small bowel obstruction.
Adhesions are bands of scar tissue that form after
surgery. The adhesions grow between sections of the
bowel and may trap loops of bowel.
- A hernia is a weakness in the wall of the abdomen through
which the bowel may protrude and become trapped.
Other causes include:
- inflammatory bowel disease, such as Crohn's disease
- inflammation from other abdominal problems, such as
diverticulitis
- intussusception, which is the intestine folding into
itself, cutting off normal flow of partly digested food
and eventually cutting off blood flow to the tissues
- a twisted or knotted bowel
- a narrowing of the bowel that has been present since
birth
- cancer.
Sometimes the blockage cuts off blood flow to part of the
bowel. When this happens, the bowel is said to be
strangulated. The lack of blood flow can cause death of
some of the tissue (gangrene) and can be life threatening.
What are the symptoms?
The symptoms of a blocked small bowel may include:
- a cramping pain in the abdomen that comes and goes
- a tender and swollen abdomen
- vomiting
- diarrhea or trouble passing gas or stools
- severe, constant pain if the blood supply has been cut
off.
How is it diagnosed?
Your healthcare provider will review your symptoms, take
your medical history, and examine you. Your provider will
ask about previous surgeries, bowel blockages, and hernias.
You may have the following tests:
- blood tests
- X-rays of the chest and abdomen
- X-rays of the bowel after a barium enema.
How is it treated?
The blockage will need to be treated at the hospital. A
tube may be passed through your nose and into your stomach
to decrease the pressure of bowel gas. Usually surgery is
done as soon as possible unless the symptoms go away and
your bowels quickly start working again.
If you need an operation, the surgeon will make a cut
through the wall of your abdomen and relieve the blockage.
The surgeon may remove a portion of bowel. Sometimes this
can be done with a laparoscope. (A laparoscope is a thin
tube with a light and tiny camera that can be put into your
abdomen through a small cut.)
You will need IV fluids to replace fluids from vomiting and
diarrhea. You may need to take antibiotics for infection.
How long will the effects last?
How long the effects last depends on what caused the
blockage and whether the bowel has been strangulated. Even
if you have an operation for treatment, an obstruction could
occur again in the future.
How can I take care of myself?
- Follow your healthcare provider's instructions.
- If you have surgery, get up and walk as soon after
surgery as is reasonable. Walking helps get the bowel to
start moving again.
How can I help prevent small bowel obstruction?
You may have little control over preventing an obstruction.
Scar tissue may form in the abdomen from surgery, injury
(such as penetrating wounds or auto accidents), and
infections (such as appendicitis). Being active after any
surgery or bowel injury may help prevent adhesions. If you
have a hernia in the abdominal wall or groin, ask your
healthcare provider if repair of the hernia would help
prevent a bowel obstruction.
This content is reviewed periodically and is subject to
change as new health information becomes available. The
information is intended to inform and educate and is not a
replacement for medical evaluation, advice, diagnosis or
treatment by a healthcare professional.
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