Gastrointestinal bleeding

Gastrointestinal (GI) bleeding is a symptom of conditions that damage the wall GI tract. GI bleeding is categorized into upper GI bleeding (UGIB) and lower GI bleeding (LGIB) depending on the source of the bleeding relative to the ligament of Treitz. In the majority of cases, bleeding is localized in the esophagus, stomach, or duodenum (UGIB). LGIB may occur in the rectum, colon, jejunum, and, in rare cases, the ileum. Gastric and duodenal ulcers are the most common causes; angiodysplasia, inflammatory diseases, and carcinomas can also cause GI bleeding. Depending on the source of the bleeding and how long the blood remains in the digestive tract, clinical symptoms may include vomiting blood (hematemesis), tarry black stool (melena), and fresh blood in the stool (hematochezia). Diagnosis includes evaluation of blood loss (e.g., hematocrit) and localization of the source of bleeding (e.g., endoscopy). Hospitalization is essential to monitor for signs of hemodynamic instability and shock caused by anemia and severe blood loss. The source of bleeding can often be located and treated simultaneously during endoscopy with injection therapy (e.g., epinephrine) or ligation.

• Upper gastrointestinal bleeding (UGIB)
  • ∼ 70–80% of GI hemorrhages ^[1][2]
  • The source of the bleeding is proximal to the ligament of Treitz.
• Lower gastrointestinal bleeding (LGIB)
  • ∼ 20–30% of all GI hemorrhages ^[2][3]
  • The source of the bleeding is distal to the ligament of Treitz (usually in the colon).

See “Differential diagnosis of lower gastrointestinal bleeding in children.”

Bleeding from the upper respiratory tract (e.g., nocturnal nosebleeds) can be mistaken for GI bleeding because the blood can be swallowed and vomited or appear in the stool as melena. Careful examination and history taking is the key to differentiating respiratory sources of bleeding from GI ones.

• Anemia due to chronic blood loss
• Acute hemorrhage: signs of circulatory insufficiency or hypovolemic shock
  • Tachycardia, hypotension (dizziness, collapse, shock)
  • Altered mental status

Both melena and hematochezia can be caused by either UGIB or LGIB.

Unexplained iron deficiency anemia in men or postmenopausal women should raise suspicion for GI bleeding.

In case of hemodynamic instability, hemodynamic resuscitation should be initiated before further diagnostic workup (see “Treatment” below).

Localization of bleeding

• Definitions
  • Occult GI bleeding: bleeding in quantities too small to be macroscopically observable (requires chemical tests or microscopic examination to be detected)
  • Overt GI bleeding: macroscopically observable bleeding with accompanying clinical symptoms (e.g., anemia, tachycardia)
• Fecal occult blood test
  • May detect small quantities of blood
  • Cannot differentiate between UGIB and LGIB ^[9]
  • A positive result should be followed up with endoscopy/colonoscopy.
• Endoscopy
  • Colonoscopy: a procedure during which a flexible fiber-optic instrument is passed through the anus to visualize the mucosa of the colon
  • Upper endoscopy: a procedure during which a flexible fiber-optic instrument is passed through the mouth to visualize the inner layer of the upper GI tract up to the duodenal papilla
  • Should be performed within 24 hours of admission ^[10]
  • Used to identify the source of intestinal bleeding (e.g., bleeding vessel, mucosal inflammation)
  • Biopsies can be taken for further diagnosis (e.g., colorectal/gastric carcinoma).
  • Therapy can be initiated immediately (e.g., epinephrine injection therapy, clipping of a bleeding vessel).
• Nasogastric tube lavage: a procedure in which a nasogastric tube is passed into the stomach and releases small amounts of liquid, which are removed with other contents of the stomach (e.g., blood in the case of GI bleeding)
  • Rule out UGIB.
  • Identify the site of bleeding and possibly initiate therapy.
  • Blood that is bright red or has a coffee-ground appearance indicates UGIB.
  • Results are negative in ∼15% of patients with UGIB.
• Other: If the above diagnostics fail to locate the source of the bleeding, evaluate for small bowel bleeding.
  • Radionuclide scan (RBCs labeled with technetium-99)
  • Video capsule endoscopy
  • Push enteroscopy
  • Angiography
    • Diagnosis of vascular etiologies (e.g., angiodysplasia)
    • Localization of the source of bleeding before surgical resection
  • Surgery/exploratory laparotomy should be considered after other therapeutic options have failed. ^[11]

Approach according to the patient's hemodynamic status

Forrest classification

The Forrest classification describes the type of lesion seen during endoscopy and helps to evaluate the risk of renewed hemorrhage (without the need for repeated intervention).

Laboratory tests ^[12]

• CBC: decreased RBCs, possibly decreased platelets
• Decreased hematocrit, decreased hemoglobin (both may be normal early in acute blood loss )
• Decreased serum ferritin and iron
• Liver function test: possibly increased ALT/AST, increased ALP
• Increased BUN ^[13]

Initial management ^[12]

• Consider elective intubation in patients with altered mental or respiratory state and severe ongoing hematemesis.
• Hemodynamic resuscitation
  • In case of hemodynamic instability and/or suspected ongoing bleeding
  • IV fluid to normalize blood pressure and heart rate (see “Fluid resuscitation”)
  • Transfusion of packed red blood cells in case of massive bleeding (e.g., hemoglobin < 7 g/dL)
• IV proton pump inhibitors (e.g., esomeprazole)
• Management of anticoagulants
  • INR 1.5–2.5: Endoscopic hemostasis is possible.
  • INR > 2.5: Reversal agents should be considered before endoscopy.

If there is any suspicion of GI bleeding, two large-caliber peripheral venous catheters should be inserted and preparations should be made for a possible blood transfusion.

Interventions to stop bleeding ^[14][15]

• Endoscopy
  • Used to locate the site of the (suspected) bleeding and to initiate therapy
    • Injection therapy (e.g., epinephrine): actively bleeding ulcers or blood vessels
    • Hemostatic surgical procedures: sclerotherapy, band ligation, cauterization; , or clip placement
    • Polypectomy in case of bleeding polyp (e.g., in the colon)
• Angiography: vasoconstriction of a bleeding vessel via e.g., intraarterial vasopressin infusion or embolization
• Surgery (laparotomy): if bleeding cannot be contained through endoscopic intervention (rarely the case)

Treatment of underlying disease

See “Treatment” sections in “Crohn disease“, “Ulcerative colitis“, “Peptic ulcer disease“, “Hemorrhoids“, “Intestinal ischemia“, “Gastric cancer“, “Colorectal cancer“, and “Portal hypertension.“

Upper GI bleed

• Erosive or inflammatory
  • Peptic ulcer disease
  • Esophagitis
  • Erosive gastritis and/or duodenitis
  • Zollinger-Ellison syndrome
  • Cameron lesion
• Vascular
  • Varices (esophageal, gastric, duodenal, ectopic)
  • Gastric antral vascular ectasia
  • Dieulafoy lesion
  • Angiodysplasia
  • Angioma
  • Osler-Weber-Rendu disease
  • Watermelon stomach
  • Blue rubber bleb nevus syndrome
  • Telangiectasias
• Portal hypertensive gastropathy
• Tumors
  • Esophageal cancer
  • Gastric cancer
• Traumatic or iatrogenic
  • Mallory-Weiss tear
  • Hiatal hernia
  • Foreign-body ingestion
  • During surgery or endoscopy
  • Aortoenteric fistula
• Coagulopathies
• Hemobilia
• Hemosuccus pancreaticus

Lower GI bleed

• Erosive or inflammatory
  • Diverticular disease
  • Ulcerative colitis
  • Crohn disease
  • Rectal ulcers
  • Stercoral ulcer
  • Celiac disease
  • Proctitis
• Vascular
  • Hemorrhoids
  • Ischemic colitis
  • Mesenteric ischemia
  • Arteriovenous malformation
  • Rectal varices
  • Angiodysplasia
  • Small bowel varices
• Tumors
  • Colorectal cancer
  • Anal cancer
  • Colonic polyps
  • Gardner syndrome
• Trauma or iatrogenic
  • Anorectal trauma
  • Lower abdominal trauma
  • During surgery or coloscopy
  • Anastomotic bleeding
  • Aortoenteric fistula
• Coagulopathies
• Anal fissures
• Brisk UGIB
• Infectious colitis/enteritis
• Radiation-induced colitis
• Fecal impaction
• Meckel diverticulum

The differential diagnoses listed here are not exhaustive.

• Hypovolemic shock
• Hepatic encephalopathy (in patients with liver cirrhosis)
• Aspiration pneumonia ^[16][17]

We list the most important complications. The selection is not exhaustive.