What are the differences in management between upper GI bleed and lower GI bleed?

Management Differences Between Upper and Lower GI Bleeding

The fundamental difference in management between upper and lower GI bleeding lies in the initial diagnostic approach: upper GI bleeding requires urgent endoscopy within 24 hours after resuscitation, while lower GI bleeding management depends on hemodynamic stability—unstable patients (shock index >1) should undergo CT angiography first, whereas stable patients can be risk-stratified for outpatient management or colonoscopy. 1, 2

Initial Assessment and Risk Stratification

Upper GI Bleeding

• Risk stratification tools (e.g., Glasgow-Blatchford score) should be used immediately in the emergency department to identify very-low-risk patients (score 0-1) who can be discharged with outpatient follow-up 3, 2
• Patients with hemodynamic instability require urgent endoscopy after initial resuscitation 4, 2
• Physical examination should focus on hemodynamic stability, abdominal tenderness, and stool color (melena suggests upper source) 3

Lower GI Bleeding

• Patients should be stratified as unstable (shock index >1) or stable, with stable bleeds further categorized as major or minor using tools like the Oakland score 1
• Minor self-terminating bleeds (Oakland score ≤8) can be discharged for urgent outpatient investigation 1
• Up to 11-15% of presumed lower GI bleeds are actually upper GI sources, particularly in patients with brisk rectal bleeding, hemodynamic compromise, elevated BUN/creatinine ratio, or antiplatelet drug use 1

Resuscitation and Transfusion Strategy

Both Upper and Lower GI Bleeding

• Restrictive red blood cell transfusion thresholds should be used: Hb trigger of 70 g/L (target 70-90 g/L) for stable patients, or 80 g/L (target 100 g/L) for those with cardiovascular disease 1, 4
• Rapid infusion of normal saline or lactated Ringer solution for hypovolemia correction 3
• Coagulopathy should be corrected early; warfarin should be interrupted at presentation, and prothrombin complex concentrate used for unstable hemorrhage 1

Pharmacologic Management

Upper GI Bleeding

• Proton pump inhibitors (PPIs) should be initiated immediately upon presentation and continued as high-dose therapy for 72 hours post-endoscopy (when rebleeding risk is highest), followed by twice-daily oral PPI for 2 weeks 3, 4, 2
• Erythromycin infusion (prokinetic) is suggested before endoscopy to improve visualization 4, 2
• For patients with cirrhosis and suspected variceal bleeding, antibiotics and vasoactive drugs (somatostatin analogues) should be started immediately 4, 5

Lower GI Bleeding

• No specific pharmacologic therapy is routinely recommended for non-variceal lower GI bleeding 1
• PPIs are not indicated unless an upper GI source is identified 1

Diagnostic Approach

Upper GI Bleeding

• Endoscopy should be performed within 24 hours of presentation after adequate resuscitation 3, 4, 2
• Earlier endoscopy (after resuscitation) is considered for high-risk patients with hemodynamic instability 4
• Nasogastric tube placement is not routinely recommended—it does not reliably aid diagnosis, affect outcomes, and causes complications in one-third of patients 1

Lower GI Bleeding

• For unstable patients (shock index >1) or active bleeding, CT angiography is the first-line investigation—it provides rapid, non-invasive localization and can identify upper GI, small bowel, or lower GI sources without bowel preparation 1
• Upper endoscopy should be performed immediately if CTA shows no source in unstable patients, as 11-15% have upper GI bleeding 1
• For stable patients with major bleeding, colonoscopy is recommended after admission 1
• If CTA, upper endoscopy, and colonoscopy are negative, video capsule endoscopy should be performed within 48 hours (diagnostic yield 87-92% if done early, dropping to <50% after 3 days) 1

Endoscopic Therapy

Upper GI Bleeding

• Endoscopic therapy is recommended for ulcers with active spurting/oozing and non-bleeding visible vessels 2
• Recommended modalities include bipolar electrocoagulation, heater probe, clips, and absolute ethanol injection 2
• Variceal bleeding requires band ligation for esophageal varices or tissue glue for gastric varices 4

Lower GI Bleeding

• Colonoscopy is the primary therapeutic modality for identified bleeding sources 1
• For post-polypectomy bleeding, colonoscopy (not CTA) should be first-line even in unstable patients, as the source is likely known 1
• Dual modality therapy (epinephrine plus one other method) is suggested, extrapolating from upper GI ulcer bleeding literature 1

Management of Rebleeding

Upper GI Bleeding

• Repeat endoscopy is suggested for recurrent bleeding 2
• If endoscopic therapy fails, transcatheter arterial embolization is the next step, followed by surgery if embolization fails 3, 2

Lower GI Bleeding

• Catheter angiography with embolization should be performed as soon as possible after positive CTA (within 60 minutes for unstable patients in centers with 24/7 interventional radiology) 1
• Vasopressin infusion controls hemorrhage in up to 91% of diverticular or angiodysplasia bleeding, but rebleeding occurs in 50% after cessation 1
• Surgery should only be considered after every effort to localize bleeding radiologically and endoscopically, except under exceptional circumstances 1
• Surgical intervention is indicated when hemodynamic instability persists despite resuscitation, transfusion requirement exceeds 6 units, or severe bleeding recurs 1

Key Pitfalls to Avoid

• Do not assume bright red rectal bleeding is always lower GI—consider upper GI source in unstable patients with risk factors 1
• Do not perform emergency laparotomy for lower GI bleeding without exhaustive radiologic/endoscopic localization attempts (operative mortality 10%) 1
• Do not delay CTA in unstable lower GI bleeding to perform colonoscopy—CTA is faster, safer, and can identify non-colonic sources 1
• Do not use liberal transfusion strategies—restrictive thresholds improve outcomes 1