What is the management algorithm for an upper gastrointestinal (GI) bleed with a negative endoscopy?

Management Algorithm for Upper GI Bleeding with Negative Endoscopy

When endoscopy fails to identify the source of upper gastrointestinal bleeding, CT Angiography (CTA) should be the next diagnostic modality, followed by video capsule endoscopy if CTA is negative. 1

Initial Assessment After Negative Endoscopy

After a negative upper endoscopy in a patient with suspected upper GI bleeding, the following steps should be taken:

1. Reassess clinical stability:

   • Continue hemodynamic monitoring
   • Maintain hemoglobin >70 g/dL (>80 g/dL in patients with cardiovascular disease) 2
   • Continue IV fluid resuscitation as needed

2. Consider the pattern of bleeding:

   • Intermittent bleeding or slow rate bleeding is often difficult to identify during endoscopy 1
   • The clinical scenario suggests obscure-overt GI bleeding (documented blood loss with negative endoscopy)

Diagnostic Algorithm

Step 1: CT Angiography (CTA)

CTA is the recommended next step after negative endoscopy for suspected upper GI bleeding 1. Benefits include:

• Ability to detect bleeding rates as slow as 0.3 mL/min 1
• High sensitivity (81%) in high-risk patients 1
• Provides anatomic and pathologic information that can guide subsequent interventions 1
• No need for oral contrast (which could interfere with subsequent procedures) 1

Step 2: If CTA is Negative

If CTA does not identify the bleeding source, proceed to one of the following based on clinical presentation:

Option A: Video Capsule Endoscopy (VCE)

• Highest diagnostic yield when performed within 48 hours of bleeding episode (up to 87-91%) 1
• Particularly useful for suspected small bowel sources 3
• Diagnostic yield decreases to <50% if performed beyond 3 days of presentation 1
• Blood on terminal ileal examination during colonoscopy strongly predicts positive VCE findings (OR: 6.13) 3

Option B: Visceral Angiography

• Consider if bleeding is more brisk or patient is unstable
• Can detect bleeding at rates as low as 0.5 mL/min 1
• Superior diagnostic yield compared to VCE in some studies, though long-term outcomes (rebleeding, hospitalization, mortality) are similar 1

Option C: Tc-99m-Labeled RBC Scan

• Can detect very slow bleeding rates (0.05-0.1 mL/min) 1, 2
• Useful when other modalities are negative but clinical suspicion remains high 1
• Limited utility for upper GI sources due to potential localization errors 1

Management Based on Diagnostic Findings

If CTA Identifies Bleeding Source:

• Active extravasation: Proceed to angiographic embolization
• Vascular abnormality without active bleeding: Consider targeted endoscopic therapy or angiography based on location and type

If VCE Identifies Bleeding Source:

• Small bowel lesion: Proceed to deep enteroscopy (single or double balloon) for therapeutic intervention
• Missed lesion in upper/lower GI tract: Repeat standard endoscopy with focus on identified area

If All Studies Negative but Bleeding Persists:

• Consider intraoperative enteroscopy as last resort
• Superselective angiography with methylene blue localization may be considered 1

Special Considerations

1. Timing is critical:

   • Emergency VCE performed immediately after negative upper endoscopy has shown 75% diagnostic yield and can guide therapy in 85% of cases 4
   • Delay in diagnostic testing reduces yield significantly

2. Contraindications to VCE:

   • Known or suspected GI obstruction
   • Swallowing disorders (can be overcome by endoscopic placement)
   • Risk of capsule retention is approximately 2% 1

3. Limitations of angiography:

   • Only detects arterial/capillary bleeding; venous bleeding may be missed 1
   • Intermittent bleeding can lead to false negatives 1
   • Variant vascular anatomy may limit diagnostic accuracy 1

4. Avoid these ineffective approaches:

   • Barium or iodinated contrast studies (interfere with subsequent procedures) 1
   • Routine second-look endoscopy is not recommended 1

By following this systematic approach, the source of upper GI bleeding can be identified in the majority of cases, even when initial endoscopy is negative, allowing for appropriate therapeutic intervention and improved patient outcomes.