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CHAPTER 105: Gastrointestinal Hemorrhage 1021

high as 50%, with angiodysplasia being the most common lesion. In common and usually results from pancreatitis-induced pseudoaneu-
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addition, this technique allows biopsy or therapy of visualized lesions. rysm formation in the splenic artery. Acquired splenic artery aneurysms
may erode into the pancreas, resulting in hemobilia without pancreatitis.
Video Capsule Endoscopy: This technique has been introduced into Hemobilia should be suspected when melena occurs in conjunction
clinical practice in the past decade and provides a noninvasive method with jaundice, blunt trauma, or acute pancreatitis. Following a negative
of examining the entire small bowel via peristaltic propulsion of the forward-viewing upper endoscopy, the endoscopist should examine the
endoscopic capsule. The patient swallows a capsule that produces duodenal papilla using a side-viewing duodenoscope. Active bleeding or
approximately 50,000 images while it traverses the small bowel over 12 a clot emanating from the papilla may be seen. Alternatively, angiogra-
to 15 hours. Recent versions of this technique are able to approximate phy may reveal active bleeding or associated aneurysms in the hepatic or
the location of the bleeding lesion within the small bowel. A limitation splenic artery. Angiographic therapy may provide temporary control of
to this test is that tissue sampling or therapeutic intervention cannot hematobilia, but generally definitive surgery is required.
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be performed. A meta-analysis of 14 prospective studies including Aortoenteric fistula is a rare development following abdominal vas-
396 patients with obscure GI bleeding showed a higher yield for clinically cular surgery involving placement of a synthetic graft. The fistula arises
significant lesions with video capsule endoscopy (VCE) (56%) than with commonly from the proximal anastomosis of the graft and communi-
PE (26%). VCE has a sensitivity of 95% and specificity of 75% com- cates with the fourth portion of the duodenum. Graft infection generally
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pared to intraoperative enteroscopy for detecting a bleeding source. 111 is present and likely plays a role in the pathogenesis of the fistula.
In addition to the preceding endoscopic modalities, enteroclysis radi- Bleeding from aortoenteric fistulas is typically intermittent and profuse.
ography can be considered for the evaluation of potential small bowel The evaluation of a suspected aortoduodenal fistula should begin with
bleeding sources, although the yield of this test is only about 10%. endoscopy. The endoscopist must examine the fourth portion of the
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This study is a double-contrast study performed by passing a tube into duodenum, where bleeding or the graft itself may be seen. If endoscopy
the proximal small bowel and injecting barium, methylcellulose, and fails to identify a fistula, angiography should be performed if the clinical
air. Despite the low sensitivity of this study, it is considered superior to suspicion is high. Surgical correction of the fistula, including removal of
standard imaging using small bowel follow-through. the graft, is necessary to prevent potential exsanguination.
Deep Enteroscopy: In the past few years, deep enteroscopy has been Meckel diverticulum should be considered in younger patients
introduced as a diagnostic and therapeutic modality to examine the presenting with massive bleeding. The diagnosis often is made by a
small bowel. It includes balloon-assisted enteroscopy (BAE) and spiral 99m Tc-pertechnetate scan, which has a sensitivity of 75%. Surgical resec-
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enteroscopy. Double-balloon enteroscopy (DBE) involves an enteroscope tion of an identified Meckel diverticulum provides definitive therapy.
with an overtube, with balloons mounted on the distal ends of each
component, and is intended for examination of the entire jejunum and
the ileum. Single-balloon enteroscopy (SBE) uses a similar concept; how- KEY REFERENCES
ever, there is only one balloon that is mounted on the overtube. The
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balloon system acts as an anchor that allows the enteroscope to be inserted • Barkun AN. International consensus recommendations on the
through the small bowel, and pleats the small intestine over the entero- management of patients with nonvariceal upper gastrointestinal
scope. BAE can be used to examine the distal small bowel through the bleeding. Ann Intern Med. 2010;152:101-113.
anterograde (per oral) or retrograde approach (per rectum). Visualizing • Chavez-Tapia NC, et al. Antibiotic prophylaxis for cirrhotic
the entire small bowel can sometimes be achieved with a combination patients with upper gastrointestinal bleeding. Cochrane Database
of anterograde and retrograde examinations. Spiral enteroscopy uses a Syst Rev. 2010;9:CD002907.
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special spiral overtube over an enteroscope. Rotating the overtube allows • Derogar M, Sandblom G, Lundell L, et al. Discontinuation of low-
the bowel to pleat over the enteroscope and allows deeper insertion. dose aspirin therapy after peptic ulcer bleeding increases risk of
The diagnostic yield of BAE ranges from 43% to 81% with similar death and acute cardiovascular events. Clin Gastroenterol Hepatol.
treatment success rates. A meta-analysis of 11 studies comparing the 2013;11:38-42.
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yield of VCE and BAE showed comparable diagnostic yields (60% vs • Fisher L, et al. The role of endoscopy in the management of
57%, respectively). BAE is an invasive procedure, and most authors obscure GI bleeding. Gastrointest Endosc. 2010;72(3):471-479.
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recommend performing a VCE first followed by BAE for diagnostic and
therapeutic purposes. • Garcia-Pagan JC, et al. Early use of TIPS in patients with cirrhosis
■ LESIONS ASSOCIATED WITH OBSCURE BLEEDING • Gralnek IM, Barkun AN, Bardou M. Management of acute bleed-
and variceal bleeding. N Engl J Med. 2010;362(25):2370-2379.
Small intestinal angiodysplasia accounts for the majority of small bowel ing from a peptic ulcer. N Engl J Med. 2008;359(9):928-937.
lesions associated with obscure bleeding. An increased incidence of • Laine L, Jensen DM. Management of patients with ulcer bleeding.
small bowel angiodyplasia has been reported in patients with end-stage Am J Gastroenterol. 2012;107(3):345-360.
renal disease (ESRD), VonWillebrand disease, and Osler-Weber-Rendu • Laine L, Shah A. Randomized trial of urgent vs. elective colo-
(OWR) syndrome. In the setting of proximal lesions located approxi- noscopy in patients hospitalized with lower GI bleeding. Am J
mately in the first 60 cm of jejunum, therapeutic push enteroscopy may Gastroenterol. 2010;105(12):2636-2641.
achieve permanent endoscopic hemostasis. More distal lesions can be • Lau JY, et al. Effect of intravenous omeprazole on recurrent bleed-
treated with BAE. In select patient populations, including those with ing after endoscopic treatment of bleeding peptic ulcers. N Engl J
ESRD, Von Willebrand disease, and OWR syndrome, hormonal therapy Med. 2000;343(5):310-316.
with estrogen, with or without progesterone, may be useful in controlling
bleeding from angiodysplasia. In patients refractory to endoscopic • Triester SL, et al. A meta-analysis of the yield of capsule endoscopy
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compared to other diagnostic modalities in patients with obscure
and medical therapy, chronic iron supplementation and periodic trans-
fusions are indicated. gastrointestinal bleeding. Am J Gastroenterol. 2005;100(11):2407-2418.
Hemobilia is bleeding from the liver, bile ducts, or pancreas and is • Villanueva C, et al. Transfusion strategies for acute upper gastroin-
characterized by blood emanating from the ampulla of Vater. Hepatic testinal bleeding. N Engl J Med. 2013;368(1):11-21.
hemobilia usually results from blunt or sharp trauma to the liver. A
hepatic artery aneurysm that erodes into the right hepatic or common REFERENCES
bile duct produces melena and occasionally presents with right upper
quadrant abdominal pain and jaundice. Pancreatic hemobilia is even less Complete references available online at www.mhprofessional.com/hall

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