What are the symptoms of a gastrointestinal (GI) bleed?

Symptoms of Gastrointestinal (GI) Bleeding

The primary symptoms of gastrointestinal bleeding include passing bright red blood per rectum, dark blood with clots, melena (black, tarry stools), hematemesis (vomiting blood), and signs of hemodynamic compromise such as pallor, fatigue, chest pain, palpitations, dyspnea, tachypnea, tachycardia, postural changes, or syncope. 1

Upper GI Bleeding Symptoms

• Melena (black, tarry stools) - The hallmark sign of upper GI bleeding, typically requiring at least 50-100 mL of blood 2
• Hematemesis - Vomiting of blood, which may be:
  • Bright red blood
  • "Coffee-ground" appearance (partially digested blood)
• Patients presenting with both hematemesis and melena typically have more severe bleeding 2
• Orthostatic hypotension - Drop in blood pressure upon standing
• Syncope or near-syncope - Fainting or feeling faint
• Tachycardia - Rapid heart rate
• Pallor - Pale appearance due to blood loss

Lower GI Bleeding Symptoms

• Hematochezia - Bright red blood per rectum or maroon-colored stool 1
• Dark blood with clots passed rectally
• Less commonly, melena can occur with lower GI bleeding 1
• Painless bleeding - Lower GI bleeding is usually painless, though associated symptoms may provide clues to the source 1

Systemic Symptoms of Significant Blood Loss

• Fatigue
• Chest pain
• Palpitations
• Dyspnea (shortness of breath)
• Tachypnea (rapid breathing)
• Postural changes in vital signs
• Syncope (fainting) 1

Associated Symptoms That May Indicate Cause

• Abdominal pain - May suggest inflammatory, infectious, or malignant lesions
• Weight loss - Could indicate malignancy
• Fever - May suggest infectious or inflammatory causes
• Diarrhea - Often present with inflammatory bowel disease
• Vomiting - May accompany upper GI bleeding
• Partial small intestinal or colonic obstruction - Could indicate malignancy 1

Special Considerations

1. Massive upper GI bleeding can present with hematochezia (bright red blood per rectum) rather than melena 2

2. Medications and foods can cause black stools that mimic melena but aren't related to bleeding:

   • Iron supplements
   • Bismuth (Pepto-Bismol)
   • Certain foods like licorice or blueberries 2

3. GI bleeding may be the presenting symptom of malignancy - In 77% of patients with GI tumor bleeding, the bleeding is the initial presenting symptom 3

4. Severity assessment should include:

   • Volume of visualized blood loss
   • Blood loss based on laboratory values (both absolute and relative to baseline)
   • Rate of blood loss
   • Response to transfusion
   • Hemodynamic parameters 1

When to Suspect Severe Bleeding

• Decrease in hematocrit value of at least 6%
• Transfusion requirement of more than two units of packed red blood cells
• Continuous active bleeding
• Persistent hemodynamic instability despite aggressive resuscitation 1

Remember that approximately 75-85% of upper GI bleeding cases cease spontaneously, but mortality remains significant (up to 14% in some studies), making prompt recognition of symptoms critical 2.