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Gastroenterology - Gastrointestinal Bleeding - Fast Facts | NEJM Resident 360

Gastrointestinal (GI) bleeding can occur from many sources and can present acutely as a medical emergency or insidiously with evidence of anemia and iron deficiency. It is a common condition encountered in both inpatient and outpatient settings. In this section, we cover upper and lower sources of GI bleeding, including Helicobacter pylori infection and peptic ulcer disease.

Upper Gastrointestinal Bleeding

Upper gastrointestinal (GI) bleeding refers to bleeding from a GI source above the ligament of Treitz.

Presentation

• usual presentation: melena, hematemesis, and symptoms of anemia

• rapid blood loss: hematochezia (representing the rapid transit of blood in severe cases)

• extreme blood loss: features of hemorrhagic shock (e.g., syncope and tachycardia)

Causes

• peptic ulcer disease (PUD)

• • the most common cause of upper GI bleeding (30%–65% of cases)

  • often associated with H. pylori infection or use of nonsteroidal anti-inflammatory drugs (NSAIDs)

• gastritis, esophagitis, duodenitis

  • associated with gastroesophageal reflux disease (GERD), pill-induced esophagitis, aspirin/nonsteroidal anti-inflammatory drug (NSAID) use, alcohol use, infections

• varices (see Liver Cirrhosis for further detail)

• Mallory–Weiss tear

• • bleeding from a laceration in the mucosa at the gastroesophageal junction, usually preceded by vomiting or retching

• tumor

• aortoenteric fistula

• arteriovenous malformation

• Dieulafoy lesion (an aberrantly dilated and tortuous submucosal arteriole, usually found in the gastric mucosa although can affect any part of the GI tract)

• gastric antral vascular ectasia (GAVE)

• • also known as watermelon stomach, with columns of red, tortuous, ectatic vessels along longitudinal folds of the gastric antrum; associated with hepatic, renal, and cardiac diseases

• procedures

  • bleeding following endoscopic procedures (e.g., polypectomy)

Evaluation

When a patient presents with an upper GI bleed, risk assessment scores such as the Glasgow–Blatchford score can be used for risk stratification of patients. A Glasgow–Blatchford score of 0 or 1 suggests low risk of complications (0.5%) and identifies patients who can be considered for outpatient management. The score comprises eight variables that give an indication of hemodynamic stability, severity of blood loss, and comorbidities.

(Source: Upper Gastrointestinal Bleeding Due to a Peptic Ulcer. N Engl J Med 2016.)

Management

Initial management: Major or significant nonvariceal upper GI bleeding is a medical emergency that requires evaluation in an emergency department or urgent care setting. For information on variceal upper GI bleeding, please see complications of cirrhosis. Key initial steps include:

• assess hemodynamic stability

• secure the airway if the patient is comatose, combative, or has massive hematemesis

• establish intravenous (IV) access with two large-bore intravenous needles (≥18 gauge) to ensure adequate volume resuscitation

• perform basic laboratory investigations, including complete blood count, metabolic panel, coagulation profile, and type and crossmatch blood sample

• correct coagulopathy as needed

• initiate IV high-dose proton pump inhibitor (PPI) therapy:

• • In a 2014 meta-analysis, intermittent bolus dosing of PPIs was equivalent to continuous infusion in patients with endoscopically treated high-risk bleeding ulcers.

• resuscitate with packed red blood cells (RBCs) if hemoglobin (Hg) <7 g/dL, patient is hemodynamically unstable, or both

• • Randomized trials have found that a restrictive transfusion threshold (Hg 7 g/dL) is superior to a liberal threshold (9 g/dL) for patients with upper GI bleed; the restrictive threshold was associated with lower mortality and rates of rebleeding than the liberal threshold group. (Read the NEJM Journal Watch summary.)

  • Red Blood Cell Transfusion Thresholds and Storage guidelines from the AABB (updated in 2016) support this restrictive transfusion threshold.

  • Note: Hemoglobin levels can take several hours to equilibrate after an episode of bleeding. If a patient is hemodynamically unstable, continuing to have large-volume bleeding, or both, transfusion should be directed to these clinical parameters and not to a specific hemoglobin threshold.

  • A threshold of 8 g/dL can be considered in patients with pre-existing cardiovascular disease, based on limited evidence.

Endoscopy and treatment: Patients who are hospitalized with significant upper GI bleeding should undergo endoscopy within 24 hours of adequate resuscitation and transfusion. Consider administration of a prokinetic agent (e.g., erythromycin) prior to endoscopy to improve visualization by emptying the stomach of blood. The goal of the procedure is to use endoscopic measures to control bleeding. Treatments differ based on endoscopic findings. Endoscopic treatment procedures include:

• injection of the bleeding site with epinephrine or alcohol

• thermal device application (cautery) to the lesion

• argon plasma coagulation

• clipping of bleeding vessels

• hemostatic powder spray

Transcatheter arterial embolization is the next treatment option in patients who do not respond to endoscopic therapy.

Rebleeding risk:

• Recurrent bleeding should be treated with repeat endoscopic therapy. Other less favored options include transcatheter arterial embolization or surgery.

• High-dose PPI therapy (defined as ≥80 mg/day) for ≥72 hours after endoscopic treatment of lesions that have high-risk characteristics (i.e., active bleeding, visible vessel, adherent clot) has been reported to reduce the risk of recurrent bleeding.

Long-term management varies based on the underlying etiology. The following diagram outlines suggested strategies:

Long-Term Treatment of Patients with Bleeding Ulcers, According to the Cause of the Ulcer

(Source: Upper Gastrointestinal Bleeding Due to a Peptic Ulcer. N Engl J Med 2016.)

H. Pylori Infection and Peptic Ulcer Disease

• H. pylori is a common cause of peptic ulcer disease (PUD) worldwide; treatment to eradicate H. pylori can reduce the risk of developing PUD and dyspepsia.

• H. pylori infection is also associated with other complications, including gastric cancer and lymphoma, iron-deficiency anemia (unrelated to PUD), and immune thrombocytopenia.

• In patients with an indication for endoscopy, direct histologic testing of gastric antral biopsies with special stains for H. pylori should be performed.

• The American College of Gastroenterology (ACG) recommends noninvasive testing with either stool antigen test or urea breath test is in patients with conditions associated with H. pylori but no indication for endoscopy. The ACG does not recommend serologic testing for H. pylori antibodies.

• Treatment of H. pylori typically involves a combination of two to three antibiotics and a PPI. Common regimens are outlined in the following table:

(Source: Helicobacter pyloriInfection. N Engl J Med 2016.)

Lower Gastrointestinal Bleeding

Approximately 30%–40% of GI bleeds occur in the lower GI tract, defined as anywhere distal to the ligament of Treitz. Patients with acute lower GI bleeding usually present with hematochezia (bright-red blood through the rectum), although they can less commonly present with melena if the bleeding is slow or intermittent. Hemodynamic instability associated with hematochezia may indicate a brisk upper GI bleed.

Causes

• Common causes of lower GI bleeding include diverticulosis, ischemic colitis, hemorrhoids, colorectal polyps and neoplasms, and colonic angioectasias.

• Rarer causes include inflammatory bowel disease, polypectomy, and NSAID-induced colopathy

Management

Initial management: Initial management of lower GI bleeding is similar to initial management of upper GI bleeding as discussed above, and involves assessment and initiation of treatment to stabilize hemodynamic status. 

Diagnosis and treatment:

• Colonoscopy within 24 hours is recommended in all patients presenting with acute lower GI bleeding, following adequate colonic preparation and hemodynamic resuscitation.

• • Observational studies have shown that earlier colonoscopy is associated with a higher likelihood of definitive diagnosis and shorter length of hospitalization.

  • Colonoscopic treatment of arteriovenous malformations (AVMs) and diverticular bleeding with clips or cautery is safe and effective.

• Upper endoscopy should be considered in patients with hematochezia and hemodynamic instability.

• Noninvasive imaging techniques (e.g., computed tomographic angiography and radionuclide technetium-99m–labeled red-cell scintigraphy) can be performed to identify the potential bleeding source, but are only diagnostic if there is active bleeding at the time of the test.

Diverticular Hemorrhage as Seen on Colonoscopy

Panel A shows active bleeding from a diverticulum, and Panel B shows postendoscopic clip placement leading to cessation of bleeding. (Source: Acute Lower Gastrointestinal Bleeding. N Engl J Med 2017.)

• Angiography and endovascular therapy can be used to identify the bleeding source and provide therapeutic interventions in patients in whom endoscopy is not successful or practical. These therapies should be considered in patients with persistent bleeding or hemodynamic instability despite resuscitative efforts.

Angiographic Diagnosis and Therapy of Acute Colonic Bleeding

Angiographic evidence of active bleeding from the right colon (the arrow points to the site of active bleeding). Image courtesy of Dr. Eli Atar, Diagnostic Imaging Department, Rabin Medical Center, Petah Tikva, Israel. (Source: Acute Lower Gastrointestinal Bleeding. N Engl J Med 2017.)

• Other treatment options: If no source of bleeding is identified with the techniques described above, other options include:

• • push enteroscopy/balloon enteroscopy to evaluate the small bowel

  • capsule endoscopy

  • surgery, in the rare instance when a patient is exsanguinating and an urgent subtotal colectomy is required

• Management of patients on anticoagulation and antiplatelets:

• • A reversal agent (e.g., vitamin K, prothrombin complex concentrate, or fresh frozen plasma) should be given to unstable patients on warfarin; otherwise warfarin should be withheld.

  • Stop low-dose aspirin for primary prevention of cardiovascular events and generally do not resume.

• However, after treatment of the GI bleed, low-dose aspirin should be continued for secondary cardiovascular prophylaxis.

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