Is Gastrointestinal Bleeding Serious? GI Bleeding Causes

Gastrointestinal (GI) bleeding can be divided into two types depending on the site of bleeding.

Upper GI bleeding

Upper GI bleeding occurs in about 80% of cases and is more common in men, with the risk increasing with age (> 60 years). The upper digestive tract is made of the esophagus, stomach, and upper part of the small intestine.

Common causes of upper GI include:

• Peptic ulcer (sore in the lining of the stomach or part of the small intestine)
• Esophageal varices (swollen veins in the esophageal lining)
• Mallory-Weiss tears (tears in the esophageal lining)
• Gastritis (inflammation in the stomach lining)
• Esophagitis (inflammation in the esophageal lining)
• Benign tumors or noncancerous growths
• Cancer

Lower GI bleeding

Lower GI bleeding occurs in about 20% of cases. Risk increases with age (a 200-fold increase from the third to ninth decades) and is somewhat more common in men. The lower digestive tract is made up of the lower part of the small intestine, large intestine, rectum, and anus.

Common causes in the lower digestive tract include:

• Hemorrhoids (enlarged veins in the rectum or anus)
• Fissures (tears in the anus)
• Angiodysplasia (growth of abnormal blood vessels in the intestine)
• Diverticulum (a pouch that forms on the wall of the large intestine)
• Diverticulitis (occurs when the pouch becomes inflamed)
• Inflammatory bowel diseases
• Polyps or cancer in the colon, rectum, or anus

Common risk factors for both upper and lower GI bleeding include:

• Bleeding disorders
• Alcohol abuse
• Long-term use of steroids, blood thinners, nonsteroidal anti-inflammatory drugs, or aspirin
• Smoking
• Prior GI or vascular surgery
• Prior GI disease or bleeding
• Ulcers
• Infections, such as Helicobacter pylori
• Liver cirrhosis
• Vascular disease
• Radiation injury to the bowels

GI bleeding may also be a sign of more serious diseases and conditions, which may include cancer of the GI tract.

Common symptoms of both upper and lower gastrointestinal bleeding include:

• Black, tarry stool
• Bloody stools
• Blood in vomit
• Vomit that looks like coffee grounds
• Weakness
• Light-headedness or fainting
• Breathing problems
• Stomach pain
• Chest pain that may mimic a heart attack
• Diarrhea
• Pale skin

Bleeding can be mild or nearly undetectable or severe and life-threatening. When bleeding is not visible to the naked eye and is only detected through laboratory tests, it is referred to as occult or hidden bleeding.

Any gastrointestinal (GI) bleeding, whether visible or hidden, should be evaluated by a doctor because it could indicate a serious underlying condition. 

Small-volume, bright red, or intermittent bleeding should be evaluated but does not constitute an emergency. Larger-volume, frequent, black, or maroon bleeding or bleeding associated with other symptoms (abdominal pain, nausea, weight loss, etc.) necessitates immediate evaluation. Notify your doctor as soon as possible if you experience GI bleeding.

Depending on your symptoms and their severity, your doctor may recommend the tests below for proper evaluation of your GI bleeding:

Lab tests

• Complete blood count: To detect anemia from blood loss
• Fecal occult blood testing: To detect occult bleeding
• Coagulation factors: Coagulopathy or bleeding disorders
• Liver function tests: To detect underlying liver disease
• Other tests: Basic metabolic panel and iron and ferritin values

Imaging

• Ultrasound
• Computed tomography with angiography
• Radionuclide imaging

Procedures

• Esophagogastroduodenoscopy
• Nasogastric lavage (placing a tube into the stomach through the nose to empty the contents)
• Colonoscopy
• Biopsy
• Angiography

Emergency care for gastrointestinal bleeding may include:

• Blood transfusions
• Intravenous fluids and medications

Once your condition has stabilized, your treatment will be determined by the cause of the bleeding. Common treatment options for GI bleeding may include:

Medications to:

• Reduce the amount of acid in the stomach 
• Treat bacterial infections
• Reduce bleeding
• Reduce inflammation

Procedures such as:

• Endoscopy
• Laparoscopic surgery

Surgery may be recommended when other methods fail or to treat conditions such as diverticulitis or uncontrolled bleeding.

To help lower your risk of GI bleeding, your doctor may review your existing medications and recommend lifestyle changes including following a healthy diet, reducing alcohol intake, and quitting smoking.