What is the management of a rectal bleed?

Management of Rectal Bleeding

The management of rectal bleeding requires prompt assessment, hemodynamic stabilization, and a systematic diagnostic approach to identify the source of bleeding, followed by appropriate therapeutic intervention based on the underlying cause. 1, 2

Initial Assessment and Resuscitation

Hemodynamic Stabilization

• Monitor vital signs continuously
• For severe bleeding:
  • Maintain hemoglobin >7 g/dL (target 7-9 g/dL) for most patients
  • Higher threshold of 8 g/dL (target 10 g/dL) for patients with cardiovascular disease
  • Maintain mean arterial pressure >65 mmHg
  • Administer IV fluids (crystalloids) for volume resuscitation
  • Avoid fluid overload which can exacerbate portal pressure and worsen bleeding 1, 2

Laboratory Evaluation

• Complete blood count
• Coagulation profile
• Type and cross-match for potential blood transfusion
• Liver function tests (if portal hypertension suspected)

Diagnostic Approach

Initial Diagnostic Tests

• Digital rectal examination
• Ano-proctoscopy or flexible sigmoidoscopy as first-line diagnostic tool 1
• For patients with high-risk features or ongoing bleeding:
  • Urgent colonoscopy within 24 hours of presentation
  • Consider upper endoscopy if lower source not identified 1, 2

Advanced Imaging (if initial tests inconclusive)

• CT Angiography (CTA) - can detect bleeding at rates of 0.3-1.0 mL/min 2
• For suspected anorectal varices:
  • EUS with color Doppler evaluation (especially for deep rectal varices)
  • Contrast-enhanced CT scan if EUS unavailable 1
• Nuclear medicine labeled red cell scan - can detect bleeding as low as 0.05-0.1 mL/min 2

Management Based on Etiology

Anorectal Varices

1. Multidisciplinary management involving hepatology specialists 1
2. For mild bleeding:
   • IV fluid replacement
   • Blood transfusion if necessary
   • Correction of coagulopathy
   • Optimal medication for portal hypertension 1
3. For severe bleeding:
   • Endoscopic treatments: variceal ligation, band ligation, sclerotherapy, or EUS-guided glue injection 1
   • Consider vasoactive drugs (terlipressin or octreotide) to reduce splanchnic blood flow 1
   • Short course of prophylactic antibiotics 1
   • Consider endorectal placement of compression tube as bridging maneuver 1

Diverticular Bleeding

1. Colonoscopy within 12-48 hours after rapid bowel preparation 3
2. If bleeding source identified:
   • Endoscopic therapy: injection with epinephrine or electrocautery 3
3. If bleeding source not identified:
   • Radionuclide imaging (technetium-99m-tagged red blood cell scan)
   • Followed by arteriography 3
4. For ongoing bleeding:
   • Consider selective embolization
   • Intra-arterial vasopressin infusion
   • Surgery as last resort 3

Traumatic Rectal Bleeding

• For penetrating trauma:
  • Colostomy and mucus fistula
  • Presacral drainage
  • Rectal washout 4
• For blunt trauma with significant injury:
  • Similar approach as penetrating trauma
  • More aggressive management of associated injuries 4

Special Considerations

Anticoagulated Patients

• Higher risk of significant bleeding
• May require reversal of anticoagulation based on severity
• More intensive monitoring and earlier intervention 5

Radiation Proctitis

• Grade 2 bleeding (requiring medication but not transfusion):
  • Responds to medication or limited coagulation in 90% of cases
• Grade 3 bleeding (requiring transfusion):
  • May require multiple coagulation treatments
  • Can have prolonged duration (median 10 months) 6

Follow-up Care

• Patients discharged with anemia should receive iron supplementation 2
• Gastroenterology follow-up within 2 weeks if discharged
• For patients with portal hypertension, consider non-selective beta-blockers for prevention of recurrent bleeding (temporarily suspend during acute bleeding) 1
• Complete colonoscopy if not performed during acute phase, especially with risk factors for colorectal cancer 1, 2

Common Pitfalls to Avoid

• Assuming rectal bleeding is always from a lower GI source (up to 15% of serious hematochezia cases have an upper GI source) 1
• Delaying endoscopic evaluation in patients with ongoing bleeding
• Overlooking the need for complete colonoscopy in patients with risk factors for colorectal cancer
• Excessive fluid resuscitation which can worsen portal hypertension and bleeding
• Failing to consider multidisciplinary management for complex cases