What is the workup for a patient presenting with gastrointestinal (GI) bleeding?

Workup for Gastrointestinal Bleeding

The workup for gastrointestinal bleeding should follow a structured approach based on hemodynamic stability, with initial stratification into unstable (shock index >1) or stable bleeding, followed by categorization of stable bleeds as major or minor using validated tools like the Oakland score.1

Initial Assessment and Stabilization

Hemodynamic Assessment

• Calculate shock index (heart rate divided by systolic blood pressure)
  • Shock index >1 indicates unstable bleeding requiring immediate intervention
  • Stable patients should be further categorized using the Oakland score

Immediate Actions for Unstable Patients

• Establish large-bore IV access
• Rapid fluid resuscitation with crystalloids
• Blood transfusion if hemoglobin <7 g/dL (or <8 g/dL in patients with cardiovascular disease)
• Correction of coagulopathy (INR >1.5) with fresh frozen plasma and vitamin K
• Correction of thrombocytopenia (<50,000/μL) with platelet transfusion

Diagnostic Pathway for Unstable Patients

1. CT angiography (CTA) as first-line investigation for hemodynamically unstable patients

   • Provides fastest and least invasive means to localize bleeding source 1
   • Should be performed immediately after initial resuscitation

2. Upper endoscopy if CTA is negative

   • Up to 15% of patients with serious hematochezia have an upper GI source 1
   • Should be performed immediately if no source identified on CTA

3. Catheter angiography with embolization if active bleeding is identified on CTA

   • Should be performed within 60 minutes for unstable patients 1

Workup for Stable Patients

Risk Stratification Using Oakland Score

• Components include: age, gender, previous LGIB admission, digital rectal exam findings, vital signs, and hemoglobin level
• Score ≤8 points: Minor bleed suitable for outpatient management
• Score >8 points: Major bleed requiring hospital admission 1

For Minor Bleeds (Oakland score ≤8)

• Discharge for urgent outpatient investigation
• Outpatient colonoscopy within 2 weeks, especially for patients >50 years with rectal bleeding 1
• Assessment of anal canal and rectum using rigid sigmoidoscopy, proctoscopy, or flexible endoscopy

For Major Bleeds (Oakland score >8)

• Hospital admission for colonoscopy
• Colonoscopy should be performed within 24 hours of presentation for patients with evidence of ongoing bleeding 1

Special Considerations

Upper vs Lower GI Bleeding Source

• Digital rectal examination is essential to confirm the presence of blood and assess for anorectal pathology
• Consider upper GI source even in suspected lower GI bleeding:
  • Up to 15% of patients with hematochezia have an upper GI source 1
  • Upper endoscopy should be performed if no clear source is identified in lower GI tract

Anticoagulation Management

• Interrupt warfarin therapy at presentation 1
• Reverse anticoagulation with prothrombin complex concentrate in unstable hemorrhage
• Decisions about restarting anticoagulation should be individualized based on thrombotic risk

Common Pitfalls to Avoid

1. Failure to recognize upper GI source in presumed lower GI bleeding

   • Always consider upper endoscopy if no clear lower source is identified

2. Premature surgical intervention

   • No patient should proceed to emergency laparotomy without attempts to localize bleeding by radiological and/or endoscopic modalities 1

3. Excessive fluid resuscitation

   • Over-expansion may exacerbate portal pressure and increase risk of further bleeding 1
   • Target restoration of hemodynamic status while avoiding fluid overload

4. Inappropriate discharge of patients

   • Ensure proper risk stratification using validated tools before considering outpatient management

5. Delayed endoscopic intervention

   • Patients with high-risk features or ongoing bleeding should undergo urgent colonoscopy within 24 hours 1