Gastrointestinal Bleeding: Principles of Diagnosis and Management
Darrell M. Gray II
C. Prakash Gyawali
I. GENERAL PRINCIPLES
Acute gastrointestinal bleeding (GIB) is a common clinical emergency that leads to >300,000 hospitalizations annually.
A. Definitions: Upper GIB refers to blood loss proximal to the ligament of Treitz, whereas lower GIB describes bleeding distal to the ligament of Treitz.
B. The clinical history and physical exam are critical components of early risk stratification and may give insight into the etiology and site of bleeding. Rapid triage of high-risk patients allows for urgent intervention and prevention of mortality.
II. ETIOLOGY
A. Upper GIB.
1. Common causes.
a. Peptic ulcer disease.
i. This includes duodenal and gastric ulcers and erosions. Peptic ulcer disease constitutes the most common cause of upper GIB.
ii. Helicobacter pylori infection and nonsteroidal anti-inflammatory drug (NSAID) use are typical causes.
b. Varices.
i. This includes esophageal, gastric, and less frequently, duodenal varices.
ii. Typically seen with cirrhosis and portal hypertension.
iii. Isolated gastric varices can occur with splenic vein thrombosis.
c. Other esophageal causes include esophagitis and Mallory-Weiss tears.
i. Esophagitis is rarely associated with severe bleeding.
ii. Mallory-Weiss tears may be associated with vomiting and retching.
2. Uncommon causes.
a. Vascular ectasias.
i. Angiodysplasia, telangiectasia, Dieulafoy lesions, and gastric antral vascular ectasia are typical vascular ectasias seen in the foregut.
ii. Angiodysplasia can be associated with renal failure and congestive heart failure.
iii. Telangiectasia can be seen in the lips, tongue, nasopharynx, stomach, and small bowel in hereditary hemorrhagic telangiectasia (HHT).
b. Tumors, both benign (e.g., gastrointestinal stromal tumor) and malignant (e.g., adenocarcinoma, lymphoma), can be associated with GIB.
c. Other causes include portal gastropathy, Cameron lesions, aortoenteric fistula, foreign body ingestion, hemobilia, and hemosuccus pancreaticus.
B. Lower GIB.
1. Common causes.
a. Diverticulosis constitutes the most common cause of lower GIB.
b. Anorectal disease, including hemorrhoids and anal fissures.
c. Colitis including inflammatory bowel disease, infectious colitis, ischemic colitis.
d. Angiodysplasia.
e. Tumors and polyps, including postpolypectomy bleeding.
2. Uncommon causes.
a. Rectal ulcers including stercoral ulcers and solitary rectal ulcer syndrome.
b. Radiation proctopathy and colopathy.
c. Vasculitis.
d. Meckel diverticulum.
e. Colonic varices.
f. Other causes, including endometriosis, intussusception, aortoenteric fistula.
III. DIAGNOSIS
A. Clinical presentation.
1. Hematemesis consists of vomiting of either fresh blood or altered blood (coffee-ground emesis). This is indicative of acute upper GIB.
2. Hematochezia consists of passage of bright or dark red blood through the anus.
a. This is most commonly a manifestation of lower GIB.
b. Brisk upper GIB can manifest as hematochezia, when it is almost invariably associated with hemodynamic instability.
3. Melena consists of passage of black, sticky, tarry stools.
a. Frequently the result of an upper GIB, but can be seen in slow lower GIB.
b. Melena can persist for several days after GIB has ceased, and the stool may remain positive for occult blood for up to 2 weeks.
B. Diagnostic tests.
1. Nasogastric aspiration and lavage can be helpful in risk stratification when acute upper GIB is suspected.
a. Aspiration of red blood should prompt urgent endoscopy for further investigation and/or treatment.
b. Lavage may help remove clots from the stomach in preparation for endoscopy and provide an indication of the acuity and rapidity of bleeding.
c. The nasogastric aspirate may be nonbloody if a tightly closed pylorus prevents reflux of blood from a duodenal bleeding site.
2. Conventional endoscopy.
