git bleeding

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ACUTE UPPER
GASTROINTESTINAL HEMORRHAGE
Upper GI bleeding refers to bleeding that
arises from the GI tract proximal to the
ligament of Treitz
Common Causes of Upper
Gastrointestinal Hemorrhage
NONVARICEAL BLEEDING
(80%)
Peptic ulcer disease 3050%
Mallory-Weiss tears 1520%
Gastritis or duodenitis 1015 Esophagitis 5-10%
Arteriovenous
malformations 5%
Tumors 2%
PORTAL HYPERTENSIVE
BLEEDING (20%)
Gastroesophageal varices
>90%
Hypertensive portal
gastropathy <5%
Isolated gastric varices
Rare
Although patients with cirrhosis are at high
risk for developing variceal bleeding, even
in these patients, nonvariceal sources
account for most of the episodes of GI
hemorrhage
The foundation of diagnosis and management of
patients with an upper GI bleed is an EGD. Multiple
studies have demonstrated that early EGD (within
24 hours) results in
reductions in blood transfusion requirements, a
decrease in the need for surgery,
and a shorter length of hospital stay.
Endoscopic identification of the source of bleeding
also permits an estimate of the risk for subsequent
or persistent hemorrhage as well as facilitating
operative planning, should that prove necessary.
In general, 20% to 35% of patients undergoing EGD
will require a therapeutic endoscopic intervention,
and 5% to 10% will eventually require surgery
Peptic Ulcer Disease
PUD still represents the most frequent cause of upper
GI hemorrhage, accounting for about 40% of all
cases
Bleeding develops as a consequence of acid-peptic
erosion of the mucosal surface.
Although chronic blood loss is common with any
ulcer, significant bleeding typically results when
there is involvement of an artery, either of the
submucosa or, with penetration of the ulcer, an
even larger vessel.
.
Although duodenal ulcers are more common
than gastric ulcers, gastric ulcers bleed
more commonly; as a result, in most series,
the relative proportions are nearly equal.
The most significant hemorrhage occurs
when duodenal or gastric ulcers penetrate
into branches of the gastroduodenal artery
or left gastric artery, respectively
Algorithm for the diagnosis and
management of nonvariceal upper GI
bleeding
Indications for Surgery in
Gastrointestinal Hemorrhage
Hemodynamic instability despite vigorous
resuscitation (>6 units transfusion)
Failure of endoscopic techniques to arrest
hemorrhage
Recurrent hemorrhage after initial stabilization
(with up to two attempts at obtaining
endoscopic hemostasis)
Shock associated with recurrent hemorrhage
Continued slow bleeding with a transfusion
requirement exceeding 3 units/day
Mallory-Weiss Tears
Mallory-Weiss tears are mucosal and submucosal
tears that occur near the gastroesophageal
junction. Classically, these lesions develop in
alcoholic patients after a period of intense retching
and vomiting after binge drinking, but they can
occur in any patient who has a history of repeated
emesis.
The mechanism, proposed by Mallory and Weiss in
1929, is forceful contraction of the abdominal wall
against an unrelaxed cardia, resulting in mucosal
laceration of the proximal cardia as a result of the
increase in intragastric pressure.
Stress Gastritis
Stress-related gastritis is characterized by the
appearance of multiple superficial erosions of the
entire stomach, most commonly in the body.
It is thought to result from the combination of acid
and pepsin injury in the context of ischemia from
hypoperfusion states, although NSAIDs produce a
very similar appearance.
it was a commonly encountered lesion in critically ill
patients, with significant morbidity and mortality
from bleeding. These lesions are different from the
solitary ulcerations, related to acid hypersecretion,
that occur in patients with severe head injury
(Cushing's ulcers).
When stress ulceration is associated with major burns,
these lesions are referred to as Curling's ulcers.
In contrast to NSAID-associated lesions, significant
hemorrhage from stress ulceration was a common
phenomenon.
Esophagitis
The esophagus is infrequently the source of significant
hemorrhage. When it does occur, it is most commonly the
result of esophagitis. Esophageal inflammation secondary
to repeated exposure of the esophageal mucosa to the
acidic gastric secretions in gastroesophageal reflux disease
(GERD) leads to an inflammatory response, which can result
in chronic blood loss. Ulceration may accompany this
process, but the superficial mucosal ulcerations generally do
not bleed acutely, but rather present as anemia or guaiacpositive stools. A variety of infectious agents may also
cause esophagitis, particularly in the immunocompromised
host ( Fig. 46-5 ). With infection, hemorrhage can
occasionally be massive. Other causes of esophageal
bleeding include medications, Crohn's disease, and
radiation.
Dieulafoy's Lesion
Dieulafoy's lesions are vascular malformations found
primarily along the lesser curve of the stomach within 6
cm of the gastroesophageal junction, although they can
occur elsewhere in the GI tract ( Fig. 46-6 ). They
represent rupture of unusually large vessels (1-3 mm)
that are found in the gastric submucosa. Erosion of the
gastric mucosa overlying these vessels leads to
hemorrhage. The mucosal defect is usually small (2-5
mm) and may be difficult to identify. Given the large
size of the underlying artery, bleeding from a
Dieulafoy's lesion can be massive.
Malignancy
Malignancies of the upper GI tract are usually associated
with chronic anemia or hemoccult-positive stool rather
than episodes of significant hemorrhage.
On occasion, malignancies present as ulcerative lesions
that bleed persistently.
This is perhaps most characteristic of the GI stromal
tumor (GIST), although it may occur with a variety of
other lesions, including leiomyomas and lymphomas.
Although endoscopic therapy is often successful in
controlling hemorrhage, the rebleeding rate is high;
therefore, when a malignancy is diagnosed, surgical
resection is indicated.
Gastric Antral Vascular
Ectasia
Also known as “watermelon stomach,” gastric antral
vascular ectasia (GAVE) is characterized by a
collection of dilated venules appearing as linear red
streaks converging on the antrum in longitudinal
fashion, giving it the appearance of a watermelon.
Acute severe hemorrhage is rare in GAVE, and most
patients present with persistent, iron deficiency
anemia from continued occult blood loss.
Aortoenteric Fistula
Primary aortoduodenal fistulas are rare
lesions developing in up to 1% of aortic
graft cases
Hemobilia
Hemobilia is often a difficult diagnosis to make.
It is typically associated with trauma, recent instrumentation
of the biliary tree, or hepatic neoplasms.
This unusual cause of GI bleeding is suspected in anyone who
presents with hemorrhage, right upper quadrant pain, and
jaundice.
Unfortunately, this triad is seen in less than half of patients,
and a high index of suspicion is required. Endoscopy can be
helpful by demonstrating blood at the ampulla.
Angiography is the diagnostic procedure of choice. If diagnosis
is confirmed, angiographic embolization is the preferred
treatment.
Hemosuccus Pancreaticus
Another rare cause of upper GI bleeding is bleeding from the
pancreatic duct, or hemosuccus pancreaticus.
This is typically caused by erosion of a pancreatic pseudocyst
into the splenic artery.
It presents with abdominal pain and hematochezia.
As with hemobilia, it is a difficult diagnosis to make and
requires a high index of suspicion in patients with
abdominal pain, blood loss, and a past history of
pancreatitis.
Angiography is diagnostic and permits embolization, which is
often therapeutic. In cases that are amenable to a distal
pancreatectomy, this procedure often results in cure.
Iatrogenic Bleeding
Upper GI bleeding may follow therapeutic or diagnostic
procedures. As described, hemobilia may be iatrogenic in
nature, particularly after percutaneous transhepatic
procedures. Another common cause of iatrogenic
bleeding is endoscopic sphincterotomy. This can occur in
up to 2% of cases. It is often mild and self-limited. Late
hemorrhage usually occurs within the first 48 hours and
may require injection of the area with epinephrine.
Surgical intervention is rarely required.
Percutaneous endoscopic gastrostomy (PEG) placement is
an increasingly common procedure. Bleeding rates of up
to 3% have been reported. Although most of these cases
reflect bleeding from the incision site, some are due to
bleeding from the gastric mucosa ( Fig. 46-8 ). This can
often be controlled endoscopically.
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