What is the initial management for a patient with diverticular bleeding?

Initial Management of Diverticular Bleeding

Patients with diverticular bleeding require immediate hemodynamic assessment using shock index (heart rate/systolic BP), followed by resuscitation with restrictive transfusion strategy (Hb trigger 70 g/L), and urgent colonoscopy within 12-24 hours after rapid bowel preparation for both diagnosis and endoscopic hemostasis. 1, 2, 3

Immediate Resuscitation and Stabilization

Calculate shock index immediately to stratify patients as stable (≤1) or unstable (>1), which determines the entire diagnostic and therapeutic pathway. 3

• Initiate fluid resuscitation with crystalloids (normal saline or lactated Ringer's solution) to restore hemodynamic stability and maintain mean arterial pressure >65 mmHg. 2, 3

• Use restrictive transfusion thresholds: transfuse red blood cells when hemoglobin drops below 70 g/L (7 g/dL), targeting 70-90 g/L range for hemodynamically stable patients without cardiovascular disease. 2, 3

• For patients with cardiovascular disease, use a hemoglobin trigger of 80 g/L (8 g/dL) with target ≥100 g/L. 3

• Monitor hourly urine output targeting >30 mL/hour in severe cases to assess adequate perfusion. 2

Diagnostic Pathway Based on Hemodynamic Status

For Unstable Patients (Shock Index >1)

Perform CT angiography immediately as the first-line investigation—it is the fastest, least invasive method to localize active bleeding before planning any intervention. 1, 3

• If CTA is positive, proceed to catheter angiography with embolization within 60 minutes in centers with 24/7 interventional radiology access. 1

• If CTA shows no source, perform upper endoscopy immediately, as 11-15% of presumed lower GI bleeds are actually upper GI sources, particularly with brisk rectal bleeding and hemodynamic compromise. 1

For Stable Patients with Major Bleeding

Perform urgent colonoscopy within 12-24 hours after hemodynamic stabilization—this is the recommended first-line diagnostic and therapeutic approach. 2, 4

• Administer rapid bowel preparation with 4-6 liters of polyethylene glycol solution over 3-4 hours before colonoscopy to optimize visualization. 2, 4

• Use CO2 insufflation during colonoscopy to reduce gas explosion risk in poorly prepared colons. 2

Endoscopic Hemostasis

When a bleeding diverticulum is identified, perform endoscopic therapy using clipping, injection therapy, thermal therapies, endoscopic band ligation, or hemostatic powders. 2, 5

• Endoscopic band ligation shows superior outcomes with lower early rebleeding rates (6%) compared to clipping (33%). 2

• Consider dual modality therapy (epinephrine injection plus one other method) extrapolating from upper GI ulcer bleeding literature. 1

• Over-the-scope clips (OTSC) are effective for severe diverticular bleeding, especially in cases of rebleeding after first-line conventional endoscopic procedures. 6

When Endoscopy Fails or Is Not Feasible

Consider angiography with embolization when endoscopic visualization or treatment fails, or when there is ongoing severe bleeding with hemodynamic instability. 2, 7

• Technical success rates for embolization are 93-100% regardless of embolic agent used. 2

• Angiography requires active bleeding at rates >0.5 mL/min to localize a bleeding site. 8

Surgical Intervention

Surgery should only be considered after exhaustive radiologic and endoscopic localization attempts, except in exceptional circumstances, as operative mortality is approximately 10%. 1, 2

Surgical indications include:

• Hemodynamic instability persisting despite resuscitation 1, 2

• Transfusion requirement exceeding 6 units 1

• Severe bleeding recurrence 1

• Ongoing bleeding despite endoscopic and angiographic interventions 2

• When the bleeding source is localized preoperatively, segmental colectomy is preferred with mortality rate of 5-10% and rebleeding rate of 14% at 1 year. 2, 7

• When localization is not possible, subtotal colectomy may be necessary. 7

Critical Pitfalls to Avoid

Do not delay CTA in unstable patients to perform colonoscopy—CTA is faster, safer, and can identify non-colonic sources. 1

Do not assume all bright red rectal bleeding is lower GI—up to 15% have upper GI sources, particularly in patients with hemodynamic compromise or antiplatelet drug use. 1

Do not use liberal transfusion strategies—restrictive thresholds (Hb 70 g/L) improve outcomes and avoid fluid overload. 1, 2

Do not perform emergency laparotomy without localization attempts—blind surgery has high mortality and rebleeding rates. 1

Admission and Monitoring

Admit patients to intensive care unit if there is severe bleeding or significant comorbidities, as approximately 80% of diverticular hemorrhage resolves spontaneously but requires close monitoring. 4, 7

Patients should be admitted to hospitals with 24/7 access to endoscopy, interventional radiology (on-site or via formal network), abdominal surgery, and critical care, as lack of IR access is independently associated with mortality. 8