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Gastrointestinal Bleeding
Mehrdad Esmailian MD.
Assistant professor of Emergency Medicine
Epidemiology
• Gastrointestinal (GI) bleeding is a
relatively common problem encountered in
emergency medicine that requires early
consultation and often admission
• The overall mortality of GI bleeding is
approximately 10%
• Diagnostic modalities have improved much
more than therapeutic techniques
• GI bleeding is often easy to identify when
there is clear evidence of vomiting blood
or passing blood in the stool, but it may
present subtly with signs and symptoms of
hypovolemia, such as dizziness, weakness,
or syncope
• The approach to GI bleeding depends on
whether the hemorrhage is located in the
proximal or distal segments of the GI
tract (i.e., upper or lower GI bleeding)
• These segments are defined by the
ligament of Treitz in the fourth section of
the duodenum
• In the United States, upper GI bleeding
(UGIB) affects 50 to 150 people per
100,000 population each year and results
in 250,000 admissions at an estimated
annual cost of almost $1 billion
• Lower GI bleeding (LGIB) affects a
smaller portion of patients and results in
proportionally fewer hospital admissions
than UGIB
• GI bleeding can occur in individuals of any
age, but most commonly affects people in
their 40s through 70s (mean age 59 years)
• Most deaths caused by GI bleeding occur
in patients older than age 60 years
• UGIB is more common in men than women
(2:1), whereas LGIB is more common in
women
• Significant UGIB requiring admission is
more common in adults, whereas LGIB
requiring admission is more common in
children
Differential
Considerations
• Peptic ulcer disease, gastric erosions, and
varices account for approximately three
fourths of adult patients with UGIB
• Diverticulosis and angiodysplasia account
for approximately 80% of adults with
LGIB
• Esophagitis, gastritis, and peptic ulcer
disease are the most common causes of
UGIB in children, and infectious colitis and
inflammatory bowel disease are the most
common causes of LGIB in children
• In children younger than age 2 years,
massive LGIB is most often a result of
Meckel's diverticulum or intussusception
• At all ages, anorectal abnormalities are
the most common cause of minor LGIB
• Despite improved diagnostic techniques, no
source of bleeding is identified in
approximately 10% of patients with GI
bleeding
• Patients who have abdominal aortic grafts
who present to the emergency department
with GI bleeding should receive prompt
surgical consultation in the emergency
department for the possibility of
aortoenteric fistula
Rapid Assessment
and Stabilization
• Most patients with GI bleeding are easy to
diagnose because they present to the
emergency department complaining of
vomiting blood or passing black or bloody
stool
• The diagnosis is confirmed quickly by
examination of the stool for the presence
of blood
• Patients with suspected GI bleeding who
are hemodynamically unstable should
undergo rapid evaluation and resuscitation
• They should be undressed quickly, placed
on cardiac and oxygen saturation monitors,
and given supplemental oxygen as needed
• At least two large-bore peripheral
intravenous lines should be placed
(minimum 18-gauge); blood should be drawn
for hemoglobin or hematocrit, platelet
count, prothrombin time (PT), and type and
screen or type and crossmatch; and
crystalloid
resuscitation
should
be
initiated
• Intravenous crystalloid fluid should be
given as a 2-L bolus in adults or 20 mL/kg
in children until the patient's vital signs
have stabilized or the patient has received
40 mL/kg of crystalloid
• Patients who remain unstable after 40
mL/kg of crystalloid should be given type
O, type-specific, or crossmatched blood
depending on availability
• Persistently unstable patients should
receive immediate consultation
 patients
with
UGIB
with
a
gastroenterologist and surgeon
 patients with LGIB with a surgeon
Pivotal Findings
• Keys to diagnosing GI bleeding :
 History
 physical examination
 testing stool for blood
 measuring hemoglobin or hematocrit
History
• Patients usually complain of vomiting red
blood or coffee ground–like material or
passing black or bloody stool
• Hematemesis (vomiting blood) occurs with
bleeding of the esophagus, stomach, or
proximal small bowel. Approximately 50%
of patients with UGIB present with this
complaint
• Hematemesis may be bright red or darker
(i.e., coffee ground–like) as a result of
conversion of hemoglobin to hematin or
other pigments by hydrochloric acid in the
stomach
• The color of vomited or aspirated blood
from the stomach cannot be used to
determine if the bleeding is arterial or
venous in nature
• Melena, or black tarry stool, occurs from
approximately 150 to 200 mL of blood in
the GI tract for a prolonged period.
Melena is present in approximately 70% of
patients with UGIB and a third of patients
with LGIB
• Black stool that is not tarlike may result
from 60 mL of blood from the upper GI
tract
• Blood from the duodenum or jejunum must
remain in the GI tract for approximately 8
hours before turning black
• Occasionally, black stool may follow
bleeding into the lower portion of the
small bowel and ascending colon
• Stool may remain black and tarry for
several days, even though bleeding has
stopped
• Black stool also may be seen after
ingestion of bismuth (e.g., Pepto-Bismol),
which can confuse the situation because it
is often taken for UGI distress. In
contrast to melena, stool rendered black
by bismuth is not positive on Hemoccult
testing
• Hematochezia, or bloody stool (bright red
or maroon), most often signifies LGIB, but
may be due to brisk UGIB with rapid
transit time through the bowel
• Because UGIB is much more common than
LGIB, a more proximal source of
significant bleeding must be excluded
before assuming the bleeding is from the
lower GI tract
• Approximately two thirds of patients with
LGIB present with red blood per rectum
• Small amounts of red blood (e.g., 5 mL)
from rectal bleeding, such as bleeding due
to hemorrhoids, may cause the water in
the toilet bowl to appear bright red.
Bright red stools also can be seen after
ingestion of a large quantity of beets, but
Hemoccult testing would be negative
• When taking the history, specific
questions should address the duration and
quantity of bleeding, associated symptoms,
previous history of bleeding, current
medications, alcohol, nonsteroidal antiinflammatory drug and long-term aspirin
ingestion, allergies, associated medical
illnesses, previous surgery, treatment by
prehospital personnel, and the response to
that treatment
• Patients with GI bleeding may complain of
symptoms of hypovolemia, such as
dizziness,
weakness,
or
loss
of
consciousness, most often after standing
up
• Other nonspecific complaints include
dyspnea, confusion, and abdominal pain
• Rarely an elderly patient may present with
ischemic chest pain from significant
anemia
• One in five patients with GI bleeding may
have only nonspecific complaints
• History is of limited help in predicting the
site or quantity of bleeding
• Patients with a previously documented GI
lesion bleed from the same site in only
60% of cases
• Gross estimates of blood loss based on the
volume and color of the vomitus or stool
(e.g., brown or black, pink or red) or the
number of episodes of hemorrhage are
notoriously inaccurate
Physical
Examination
Vital Signs
• Vital signs and postural changes in heart
rate have been used to assess the amount
of blood loss in patients with GI bleeding
but are notoriously insensitive and
nonspecific, with the exception of
significant, sustained heart rate increase
• All patients with a history suggesting GI
bleeding who are hypotensive, are
tachycardic, or have sustained postural
changes of greater than 20 beats/min in
heart rate should be assumed to have
significant hemorrhage
• Normal vital signs do not exclude
significant hemorrhage
• Postural changes in heart rate and blood
pressure may occur in individuals who are
not bleeding (e.g., elderly people, many
normal
individuals,
individuals
with
hypovolemia from other causes)
General Examination
• The physical examination is valuable in
making the diagnosis and assessing the
severity of blood loss and a patient's
response to that loss
• Careful attention is given to the patient's
general appearance, vital signs, mental
status (including restlessness), skin signs
(e.g., color, warmth, and moisture to assess
for
shock
and
lesions
such
as
telangiectasia, bruises, or petechiae to
assess
for
vascular
diseases
or
hypocoagulable states), pulmonary and
cardiac findings, abdominal examination,
and rectal and stool examination
• Frequent reassessment is important
because a patient's status may change
quickly
Rectal Examination
• Rectal and stool examination are often key
to making or confirming the diagnosis of
GI bleeding
• The finding of red, black, or melenic stool
early in the assessment is helpful in
prompting
early
recognition
and
management of patients with GI bleeding
• The absence of black or bloody stool does
not exclude the diagnosis of GI bleeding
• Regardless of the apparent character and
color of the stool, occult blood testing is
indicated
Ancillary Testing
Tests for Occult Blood
• The presence of hemoglobin in occult
amounts in stool is confirmed by tests
such as guaiac (e.g., Hemoccult) Stool
tests for occult blood may have positive
results 14 days after a single, major
episode of UGIB
• False-positive
results
have
been
associated with ingestion of red fruits and
meats, methylene blue, chlorophyll, iodide,
cupric sulfate, and bromide preparations
• False-negative results are uncommon but
can be caused by bile or ingestion of
magnesium-containing antacids or ascorbic
acid. may show that it is maternal in origin
• Tests to evaluate gastric contents for
occult blood (e.g., Gastroccult) can be
unreliable and should not be used for this
purpose
• In newborns, maternal blood that is
swallowed may cause bloody stools; ; the
Apt test may show that it is maternal in
origin
Clinical Laboratory Tests
• Blood should be drawn for evaluation of
baseline
hematocrit
or
hemoglobin,
coagulation studies (PT and platelet count),
and type and crossmatch (or type and
screen if the patient is stable)
• Hematocrit and hemoglobin are clinically
useful tests that may be obtained at the
patient's
bedside,
but
they
have
significant limitations
• The initial hematocrit may be misleading in
patients with preexisting anemia or
polycythemia
• Changes in the hematocrit may lag
significantly behind actual blood loss
• Infusion
of
normal
saline
speeds
equilibration of the hematocrit; how-ever,
rapid infusion of crystalloid in nonbleeding
patients also may cause a decrease in
hematocrit by hemodilution
• The optimal hematocrit with respect to
oxygen-carrying capacity and viscosity in
critically ill patients has been reported to
be 33%
• In general, patients with hemoglobin of 8
g/dL or less (hematocrit <25%) from acute
blood loss usually require blood therapy
• After transfusion and in the absence of
ongoing blood loss, the hematocrit can be
expected to increase approximately 3%
for each unit of blood administered
(hemoglobin increases by 1 mg/dL)
• PT should be used to determine whether a
patient has a preexisting coagulopathy
• An elevated PT may indicate vitamin K
deficiency, liver dysfunction, warfarin
therapy, or consumptive coagulopathy
• Patients
receiving
therapeutic
anticoagulants or patients with an elevated
PT and evidence of active bleeding should
receive sufficient fresh frozen plasma to
correct the PT
• Serial platelet counts are used to
determine
the
need
for
platelet
transfusions (i.e., if <50,000/mm3)
Blood Bank
• Blood should be sent for type and hold or
type and crossmatch early in the patient's
care
• Immediate transfusion needs in unstable
patients can be met with O-positive
packed red blood cells (O-negative packed
red blood cells in women of childbearing
age whose Rh status is unknown)
• Within 10 to 15 minutes, type-specific
blood is usually available
• Group O and type-specific blood are safe
for patients and result in few transfusion
reactions
• Fully crossmatched blood may take 60
minutes to prepare
• Stable patients can be managed more costeffectively by ordering “type and hold” for
several units of blood
Other Laboratory Tests
• Determination of electrolytes, BUN, and
creatinine may be useful in a small
percentage of patients with GI bleeding
when indicated
• Patients with repeated vomiting may
develop hypokalemia, hyponatremia, and
metabolic alkalosis, which usually correct
with adequate hydration and resolution of
vomiting
• Patients with shock often have metabolic
acidosis from lactate accumulation
• The BUN is elevated in many patients with
UGIB as a result of the absorption of
blood from the GI tract and hypovolemia
causing prerenal azotemia. After 24 hours,
hypovolemia
is
probably
the
sole
determinant of azotemia unless there has
been recurrent bleeding
Electrocardiogram
• An electrocardiogram should be obtained
on all patients older than age 50; patients
with preexisting ischemic cardiac disease;
patients with significant anemia; and all
patients with chest pain, shortness of
breath, or severe hypotension
• Asymptomatic myocardial ischemia (ST
segment depression >1 mm) or injury (ST
segment elevation >1 mm) may develop in
the setting of GI bleeding. Patients with
GI
bleeding
and
clinical
or
electrocardiogram evidence of myocardial
ischemia should receive packed red blood
cells as soon as they are available and
appropriate treatment for ischemia
Imaging
• GI hemorrhage is not an indication for
plain abdominal radiography
• An upright chest radiograph should be
performed in patients with UGIB
suspected of aspiration or with signs and
symptoms of bowel perforation (shock
with
significant
abdominal/peritoneal
tenderness)
DIFFERENTIAL
DIAGNOSIS
• Swallowing blood from the nose or oral
cavity may cause hematemesis or melena
• Red vomitus may be due to food products
(e.g., Jell-O, tomato sauce, wine), and black
stool may be due to iron therapy or
bismuth (e.g., Pepto-Bismol)
• Hypovolemia (and its symptoms) may be
due to vomiting and diarrhea without
bleeding. Poor oral intake with or without
fever also may result in hypovolemia
• Usually the patient's hemoglobin or
hematocrit is normal or elevated until
hemodilution can occur
• There are many causes of anemia other
than GI bleeding, and the absence of
suggestive symptoms or blood in the stool
makes GI bleeding less likely the cause
MANAGEMENT
• Keys
to
appropriate
management :
 Quick identification
 aggressive resuscitation
 risk stratification
 prompt consultation
emergency
Reassurance
• Patients who present to the emergency
department with symptoms and signs of GI
bleeding are often frightened. They may
be concerned about the possibility of
painful procedures and of the real or
perceived risk of death
• These patients and their families should
be treated in a supportive and reassuring
manner
• They should be provided with accurate
information about their problem, and all
aspects of the care they are receiving
should be explained in a way that they
understand
Nasogastric Tube and
Gastric Lavage
• After initial resuscitation of the patient,
it is important to identify whether the
hemorrhage is proximal or distal to the
ligament of Treitz (i.e., UGIB or LGIB)
• If the patient's vomitus can be inspected
for blood or has been reported by the
patient as bloody or “coffee grounds” or if
melenic stool is present, an upper GI bleed
should be the first consideration
• Placement of a nasogastric tube is
generally not necessary and rarely yields
information that is independently useful
for either diagnosis or risk stratifications
• Aspiration of bloody contents diagnoses
UGIB (or bleeding from nasal or oral
passageways),
but
it
does
not
differentiate if the bleeding is ongoing or
has already stopped
• There is a 10% incidence of failure to
aspirate blood in established UGIB
• False-negative results may occur if the
bleeding is intermittent or has already
stopped and the stomach cleared or if the
bleeding is in the duodenum, and edema or
spasm of the pylorus has prevented reflux
of blood into the stomach.
• The presence of bile in an otherwise clear
aspirate excludes the possibility of active
bleeding above the ligament of Treitz, but
is rarely seen and should not be used to
exclude UGIB in a patient with
documented melena
• False-positive results may occur from
nasal bleeding
• Gastric contents should not be tested for
occult blood because visual inspection of
the vomitus or aspirate is insufficient to
diagnose subtle bleeding, and testing is
unreliable
• In patients who have hematochezia, an
upper GI origin for the bleeding is often
associated with signs and symptoms of
shock because rapid transit time of large
quantities of blood is producing the
hematochezia
• Because up to 11% of patients with
hematochezia have UGIB, a nasogastric
tube is indicated in most cases of LGIB
• If the gastric aspirate does not appear
bloody, the nasogastric tube should be
removed, LGIB should be considered, and
anoscopy/proctosigmoidoscopy performed
• Gastric tubes are safe in most patients,
but pharyngeal and esophageal perforation,
cardiac arrest, ethmoid sinus fracture
with brain trauma, and bronchial intubation
have been reported
• The old approach of placing a nasogastric
tube in all patients with suspected UGIB
predated endoscopy and has no place in
modern emergency medicine
• No evidence exists that gastric tube
placement aggravates hemorrhage from
varices or Mallory-Weiss tears
• Gastric lavage may be necessary to
prepare a patient for endoscopy
• Before gastric lavage, patients with
evidence of a possible perforated viscus
(e.g., severe pain, peritoneal signs) should
undergo radiologic assessment looking for
free air. Lavage should not be performed
in the presence of pneumoperitoneum
• Gastric lavage does not reduce blood loss
in patients with UGIB, and iced lavage is
not recommended
• Gastric lavage, in preparation for
endoscopy, is best performed with a largebore Ewald tube, passed orally while the
patient is in the left lateral decubitus
position with the bed in Trendelenburg
position
• Additional holes may be cut in the distal
portion of the Ewald tube to improve
aspiration of blood and clots. Clots that
cannot be aspirated continue to cause pink
return and give the false impression of
continued bleeding
• The irrigant need not be sterile; regular
tap water may be used
• The irrigant should be delivered and
removed by gravity in volumes of 200 to
300 mL until the return is clear
• Little irrigant is absorbed by the patient
• Gastric rupture has been reported as a
rare complication of gastric lavage
Anoscopy/Proctosigmoidoscopy
• Patients with mild rectal bleeding who do
not have obviously bleeding hemorrhoids
should have anoscopy/proctosigmoidoscopy
performed
• If bleeding internal hemorrhoids are
discovered, and the patient does not have
portal hypertension, the patient may be
discharged with appropriate treatment
and follow-up evaluation for hemorrhoids
• If hemorrhoids are not detected, it is
important to determine if the stool above
the rectum contains blood
• The absence of blood above the rectum in
a patient who is actively bleeding indicates
that the source of bleeding is in the
rectum
• The presence of blood above the anoscope
or sigmoidoscope does not invariably
indicate a proximal source of bleeding
because retrograde passage of blood into
the more proximal colon commonly occurs
Endoscopy
• Endoscopy is the most accurate diagnostic
tool available for the evaluation of UGIB.
It identifies a lesion in 78% to 95% of
patients with UGIB if it is performed
within 12 to 24 hours of the hemorrhage
• Accurate identification of the bleeding
site allows for risk stratification with
respect to predicting rebleeding and
mortality
• Endoscopy-based
triage
significantly
reduces hospitalization rates and costs of
treating upper GI bleeding
• Significant
advances
in
endoscopic
hemostasis also make it of therapeutic
value in select patients (e.g., banding or
sclerosing of varices). Colonoscopy is an
effective tool for diagnosis and selected
treatment of LGIB
Angiography
• Angiography can detect the location of
UGIB in two thirds of patients studied
• Since the advent of endoscopy, however,
the use of angiography has decreased
significantly, and today angiography is
used in only 1% of patients with UGIB
• Angiography is used more commonly in
patients with LGIB and usually in
consultation with a general surgeon
• Angiography rarely diagnoses the cause of
bleeding, it does identify the site of
bleeding in approximately 40% of patients
who have LGIB and 65% of patients who
eventually require surgical intervention
• Angiography ideally is performed during
active bleeding; this may be apparent by
persistently unstable vital signs or
continued transfusion requirements to
establish
or
maintain
an
optimal
hemoglobin or hematocrit level
• Arterial embolization can be used in
selected cases of LGIB
Gastric Acid Secretion
Inhibition
• All patients with documented peptic ulcer
disease should be treated with a protonpump inhibitor (e.g., omeprazole)
• There is no benefit to initiating this
therapy or administering H2 antihistamines
in the emergency department for patients
with UGIB
• When the diagnosis of peptic ulcer has
been confirmed by endoscopy, it is
appropriate to start a proton-pump
inhibitor
• Medical therapy is an adjunct, not a
substitute for endoscopic evaluation, as
appropriate
Octreotide
(Somatostatin Analogues)
• Patients with documented esophageal
varices should be treated with an
intravenous infusion of octreotide at
50 pg/hr for a minimum of 24 hours while
being observed in the intensive care unit
(ICU). It is a useful addition to endoscopic
sclerotherapy and decreases rebleeding
occurrences
Vasopressin
• Intravenous vasopressin has been used in
the treatment of patients with UGIB,
most commonly in patients with variceal
hemorrhage
• Controlled studies have not shown a
positive effect of vasopressin on overall
mortality
• These results, combined with a relatively
high rate of serious complications (9%
major and 3% fatal), suggest that use of
vasopressin should be limited
• The recommended dose of vasopressin is
20 U IV over 20 minutes, then 0.2-0.4
unit/min
• Consultation with a gastroenterologist is
advisable
Sengstaken-Blakemore
Tube
• The Sengstaken-Blakemore tube stops
hemorrhage in approximately 80% of
patients bleeding from esophageal varices
• The Linton tube is superior to the
Sengstaken-Blakemore tube in patients
with bleeding gastric varices
• In general, these tubes should not be used
without endoscopic documentation of the
source of bleeding because complications
are common and significant (14% major,
3% fatal)
• Indication : an exsanguinating patient with
probable variceal bleeding in whom
endoscopy is not immediately available and
vasopressin
has
not
slowed
the
hemorrhage
• Consultation
with
a
surgeon
or
gastroenterologist is advisable
Surgery
• Surgery
is
indicated
for
all
hemodynamically unstable patients with
active bleeding who do not respond to
appropriate
intravascular
volume
replacement,
correction
of
any
coagulopathy, and endoscopic intervention
(if available)
• The mortality for patients undergoing
emergency operations for GI bleeding is
approximately 23%
• Generally, surgery is indicated whenever
the risk of ineffective medical therapy
and continued hemorrhage outweighs that
of surgical morbidity and mortality
• Emergency surgery should be considered
when blood replacement exceeds 5 U
within the first 4 to 6 hours or when 2 U
of blood is needed every 4 hours after
replacing initial losses to maintain normal
cardiac output
DISPOSITION
Risk Stratification
• Risk stratification involves combining
historical, clinical, and laboratory data to
determine the risk of death and
rebleeding in patients presenting to an
emergency department with GI bleeding
• Patients can
categories:
 Very low risk
 Low risk
 Moderate risk
 high risk
be
sorted
into
four
• Very low risk : patients present to the
emergency department with a chief
complaint of vomiting blood or passing
blood from their rectum but with little or
no objective evidence of significant GI
bleeding
• These patients can be sent home without
further diagnostic tests
• Before discharge, patients should be
educated about the signs and symptoms of
significant GI bleeding and when to return
to the emergency department or call their
primary care physician
• They should be given specific education
about the possible or actual cause of the
bleeding and specific treatment for the
cause of the bleeding
• They should be educated about the side
effects of any medications
• Patents should be given specific follow-up
evaluation within 24 to 36 hours
• They should be instructed to avoid aspirin,
nonsteroidal anti-inflammatory drugs, and
alcohol
• Nearly all patients with significant GI
bleeding were admitted to the hospital
• Combining clinical and endoscopic criteria
provides an accurate estimation of the risk
of rebleeding and mortality in patients
with UGIB
• These combined criteria have been used to
identify patients with UGIB who are at low
risk and can be discharged home and
patients at moderate or high risk who need
to be admitted to an appropriate care site
in the hospital
• Risk stratification for patients with LGIB
is not as well studied, and so nearly all
patients with significant LGIB are
admitted. Risk stratification can be used
for patients with LGIB, however, to decide
an appropriate inpatient care site
• Patients with clinical evidence of GI
bleeding should undergo endoscopy as soon
as it is available for final risk
stratification,
inpatient
triage,
and
determination of appropriate treatment
• If endoscopy is not immediately available,
patients with low clinical risk may be
admitted to an emergency department
observation unit or short-stay hospital bed
until endoscopy can be performed
• Patients with moderate clinical risk
criteria may be admitted to an inpatient
floor, intermediate care unit, or ICU
depending on the individual patient and the
capabilities of the institution
• Patients with high clinical risk should be
admitted to a closely monitored step-down
unit or an ICU
• The timing of endoscopy depends on
availability, the acuity of the patient, the
need for emergent therapy, the need to
determine final care site, and the need to
minimize length of stay
• Patients with LGIB that is not clearly due
to hemorrhoids, fissure, or proctitis
should be admitted to an inpatient bed
• Patients with low risk may be admitted to
the floor and set up for a nuclear medicine
imaging study (e.g., red blood cell–labeled
study) or colonoscopy
• Patients with high-risk criteria should be
admitted to a step-down unit or ICU and
be considered for angiography to identify
the site of LGIB
• Patients with moderate-risk criteria need
to be individualized for the most
appropriate inpatient care site (floor,
intermediate care bed, or ICU), and the
best diagnostic studies (nuclear imaging or
angiography)
• Consultation with a surgeon should be
obtained if it appears that more than 2 U
of blood will be required after the initial
emergency department resuscitation or if
there is reasonable suspicion that
operative intervention may be needed. This
is especially true of patients older than 65
years of age
• In general, the older the patient, the more
aggressive the surgical management ought
to be
• Patients with a history of varices,
persistent postural changes in heart rate,
or significant bright red blood per rectum
are more likely to require surgery than
patients without these findings
• Patients who have abdominal aortic grafts
who enter the emergency department with
GI bleeding should receive prompt vascular
surgical consultation in the emergency
department for the possibility of
aortoenteric fistula