Which proton pump inhibitor (PPI) should be given to a patient with melena, and what is the first workup?

PPI Selection and Initial Workup for Melena

Start high-dose intravenous PPI therapy immediately—either omeprazole or pantoprazole 80 mg IV bolus followed by 8 mg/hour continuous infusion for 72 hours—while arranging urgent upper endoscopy within 24 hours. 1

Which PPI to Give

Any PPI is acceptable as this is a class effect, but the evidence specifically supports:

• Omeprazole 80 mg IV bolus → 8 mg/hour infusion × 72 hours 1
• Pantoprazole 80 mg IV bolus → 8 mg/hour infusion × 72 hours 1

The specific dosing regimen matters more than which PPI you choose. High-dose therapy (80 mg bolus + continuous infusion) reduces rebleeding, need for surgery, and mortality in high-risk patients 1.

Route of administration: Use IV for patients presenting with melena (presumed high-risk), though oral high-dose PPI (40 mg twice daily) can be considered for lower-risk patients 1.

First Workup

Immediate Assessment (Before Endoscopy)

1. Hemodynamic status: Vital signs, orthostatics, signs of shock
2. Complete blood count: Hemoglobin/hematocrit for transfusion decisions
3. Coagulation studies: PT/INR, aPTT if on anticoagulants
4. Type and crossmatch: Prepare for potential transfusion
5. Basic metabolic panel: Assess for uremia (elevated BUN:creatinine ratio suggests upper GI source)
6. Glasgow-Blatchford Score: Calculate to stratify risk (score ≤1 = very low risk, may not require hospitalization) 2, 3

Key Clinical Details to Elicit

• Medication history: NSAIDs, aspirin, anticoagulants, antiplatelet agents, corticosteroids
• Prior GI bleeding: Single strongest risk factor for recurrence 4
• Comorbidities: Cardiovascular disease (affects transfusion threshold), liver disease
• Symptoms: Hematemesis, syncope, ongoing melena volume

Transfusion Threshold

• Hemoglobin <80 g/L for patients without cardiovascular disease
• Higher threshold for those with cardiovascular disease 2

Timing of Endoscopy

Perform upper endoscopy within 24 hours (not urgent <12 hours unless unstable) 2, 3. Early endoscopy (≤24 hours) improves outcomes; urgent endoscopy (<12 hours) does not provide additional benefit 3.

Post-Endoscopy Management

After endoscopy, adjust therapy based on findings:

• High-risk stigmata (active bleeding, visible vessel, adherent clot): Continue high-dose IV PPI for 72 hours, then switch to oral PPI 40 mg twice daily for 14 days, then once daily 2
• Low-risk stigmata (clean base, flat spot): Can feed within 24 hours and consider early discharge 1
• Test for H. pylori: All patients with ulcers should be tested and treated if positive—this is critical for preventing rebleeding 1

Common Pitfalls

• Don't delay endoscopy for PPI therapy: Start PPI immediately but don't postpone endoscopy—PPI is not a replacement for endoscopic hemostasis 1
• Don't stop aspirin: If patient is on low-dose aspirin for secondary cardiovascular prophylaxis, continue it or restart within 3-5 days 3
• Don't use standard-dose PPI: The 80 mg bolus + 8 mg/hour infusion regimen is specifically validated; lower doses may be suboptimal 1
• Don't forget H. pylori testing: This is a strong recommendation (Grade A) that significantly reduces ulcer recurrence 1