Gastrointestinal bleeding is a common clinical problem frequently requiring
hospitalization. It can vary in degrees from massive life threatening
hemorrhage to a slow, insidious chronic blood loss. The overall mortality
for severe GI bleeding is approximately 8 percent but this number is
diminishing in nature with the advent of superior diagnostic techniques
and newer medical treatments. Many bleeding episodes resolve spontaneously
but it is imperative that the bleeding site be determined as an exact
diagnosis may prevent a recurrence of bleeding and may facilitate therapeutic
maneuvers on future episodes. Also, making an accurate diagnosis can
allow a patient to be treated appropriately for the underlying condition
that caused the bleeding in the first place.
The presentation of the GI bleeding depends on the acuteness and the
source of the blood loss. Mild chronic GI blood loss may present without
any active bleeding and result in an iron deficiency anemia. In these
patients, often times they've never noted any blood loss but it occurs
in small amounts with the bowel movement so that it is not noticeable.
Often times blood in the stool can be detected by hemoccult testing
on a routine office examination. More severe cases of chronic or acute
bleeding can present with signs of anemia such as weakness, pallor,
dizziness, shortness of breath or angina. More obvious bleeding may
present with hematemesis (bloody vomitus) which may either be red in
nature or dark, coffee-like in appearance. Blood in the stool could
either be bright red in color, burgundy clotted or black and tarry in
appearance depending on the location of the bleeding source. A black,
tarry stool (melena) often indicates an upper GI source of bleeding
although it could originate from the small intestine or right colon.
Other causes of a black stool might include iron or ingestion of bismuth
(Pepto-Bismol). Hematochezia, or bright red blood per rectum can be
mixed in with the stool or after the bowel movement and usually signifies
a bleeding source close to the rectal opening. Frequently this may be
due to hemorrhoids; however, one should never assume rectal bleeding
is due to hemorrhoids until proven otherwise. Conditions like rectal
cancers, polyps, ulcerations, proctitis or infections can also cause
this type of bright red blood per rectum.
If GI bleeding is very active or severe in nature, it may require hospitalization.
Shock can occur when blood loss approaches approximately 40 percent
of blood volume and if there is evidence of hypotension or a fast heart
rate, dizziness or light-headedness, then a patient will require IV
fluids continuously with monitoring of the blood count and blood transfusion
if necessary. While in the hospital the patient will continue to be
monitored closely and certain medications will be employed in an attempt
to stop the bleeding. In addition, diagnostic tests are performed, and
if it is suspected that the bleeding is upper GI in nature, then an
upper GI endoscopy is usually the first step. This is a flexible video
endoscope that is passed through the mount into the stomach while the
patient is sedated. It allows the doctor to examine the esophagus, stomach
and duodenum for any potential bleeding site. If a site is detected,
often times therapeutic measures can be used to control the bleeding.
For example, a bleeding ulcer may be controlled with use of cautery,
laser photo therapy, injection therapy or tamponade. If the bleeding
is suspected to be originated in the lower GI tract or colon, then a
colonoscopy is usually performed which is passage of a video colonoscope
through the rectum and across the entire colon while the patient is
sedated. Other diagnostic methods for detecting a bleeding source might
include a nuclear bleeding scan, angiography, or barium GI studies.
The most common cause of an upper GI bleed is an ulceration that could
occur in the duodenum (just beyond the stomach), or in the stomach lining
itself or the esophagus. Esophageal varices, or varicose veins, are
usually the result of underlying chronic liver disease like cirrhosis
and these can often bleed very briskly. A tear at the junction of the
esophagus and stomach sometimes also occurs as a result of repeated
vomiting or retching. In addition, tumors or cancers of the esophagus
or stomach can also present with bleeding.
Factors that may aggravate upper GI bleeding include use of anti-inflammatory
medications, in particular aspirin other arthritis drugs, underlying
chronic liver disease, thinning of the blood from certain medications
like Coumadin, or underlying medical problems like chronic renal disease,
cardiac or pulmonary diseases. The most common cause of bleeding from
the lower GI tract or colon is diverticulosis. This accounts for over
40 percent of these cases. If diverticular disease is not found, then
a patient could have an angiodysplasia which is a tiny blood vessel
lining the colon that sometimes can bleed briskly or ooze chronically.
Colon cancers or colon polyps might also produce lower GI bleeding as
well as different causes for colitis. Colitis is an inflammation or
ulceration of the lining of the colon that could be due to ulcerative
colitis, Crohn's disease, radiation therapy, or poor circulation to
the colon itself.
The treatment for acute GI bleeding requiring hospitalization is as
mentioned above, and often times the bleeding will stop spontaneously.
If the bleeding persists despite all of the above-mentioned therapeutic
techniques, then on occasion surgery might be required as a last resort.
In the case of chronic low grade or occult bleeding which may result
in anemia, the work-up to discover the source of the bleeding is usually
done on an outpatient basis. Generally this consists of a colonoscopy
and/or upper endoscopy to evaluate the GI tract for any potential sources
of chronic blood loss. Once the cause for the blood loss is determined,
appropriate treatment and management recommendations can be made.