What is the next step in managing a patient with rectal bleeding?

Management of Rectal Bleeding

The first step in managing a patient with rectal bleeding is to assess vital signs, determine hemoglobin and hematocrit levels, and evaluate coagulation status to determine the severity of bleeding. 1

Initial Assessment and Stabilization

• Check vital signs immediately to assess hemodynamic stability
• Obtain complete blood count to determine hemoglobin/hematocrit levels
• Assess coagulation parameters
• In case of severe bleeding, perform blood typing and cross-matching 1
• Evaluate shock index (heart rate/systolic blood pressure) - a value >1 indicates instability 2

Resuscitation Goals (for severe bleeding)

• Maintain hemoglobin level >7 g/dL (4.5 mmol/L) during resuscitation
• Maintain mean arterial pressure >65 mmHg while avoiding fluid overload 1
• Establish at least two large-bore IV catheters for fluid resuscitation 2
• Use crystalloids for initial volume resuscitation 2
• For patients with anorectal varices and severe bleeding, follow a restrictive transfusion strategy 1

Diagnostic Evaluation

First-line Diagnostic Tools

• Ano-proctoscopy or flexible sigmoidoscopy is the recommended first-line diagnostic tool for suspected bleeding 1
• Digital rectal examination should be performed to identify obvious anorectal sources 3

Further Evaluation Based on Severity and Findings

For patients with high-risk features or ongoing bleeding:

• Perform urgent colonoscopy (plus upper endoscopy) within 24 hours 1, 2
• If colonoscopy is inconclusive or unavailable, consider:
  • Endoscopic ultrasound (EUS) with color Doppler as a second-line tool 1
  • Contrast-enhanced CT scan if bleeding site not detected by endoscopy 1
  • MRI angiography in pregnant patients (if clinically appropriate) 1

Special Considerations

• Full colonoscopy is recommended for patients with:
  • Risk factors for colorectal cancer
  • Suspicion of proximal bleeding source 1
  • Age >40 years 4
• Upper endoscopy should be considered as 15-20% of apparent lower GI bleeding actually originates from upper GI sources 5

Treatment Approach

For Mild Bleeding

• Intravenous fluid replacement if needed
• Blood transfusion if necessary
• Correction of coagulopathy
• Optimal medication for portal hypertension if anorectal varices are identified 1

For Moderate to Severe Bleeding

1. Endoscopic intervention:

   • Local procedures such as endoscopic variceal ligation, band ligation, sclerotherapy, or EUS-guided glue injection for anorectal varices 1
   • Dual modality therapy (injection plus thermal/mechanical methods) for high-risk lesions 2

2. If endoscopic treatment fails:

   • Consider interventional radiology with embolization techniques 1, 2
   • For patients with severe portal hypertension, consider TIPS (transjugular intrahepatic portosystemic shunt) if not contraindicated 1

3. Surgical intervention:

   • Consider as last resort if medical treatment, local and radiological procedures fail 1
   • Indicated for persistent hemodynamic instability despite aggressive resuscitation or requirement of >6 units of blood 2

Common Pitfalls and Caveats

• Don't assume hemorrhoids are the source: Even when hemorrhoids are present, other serious causes like colorectal cancer must be excluded, especially in patients >40 years 3, 4
• Don't miss upper GI sources: Up to 15-20% of apparent lower GI bleeding comes from upper GI sources 5
• Beware of recurrent bleeding: 80% of lower GI bleeding episodes stop spontaneously, but 25% recur, sometimes severely 5
• Consider multiple diagnoses: Patients may have more than one source of bleeding 3
• Avoid fluid overload: Excessive fluid resuscitation can exacerbate portal pressure and increase risk of further bleeding in patients with varices 1

Special Populations

• Patients with liver disease: Early involvement of hepatology specialist team is recommended 1
• Patients on anticoagulants: Correction of coagulopathy is essential, with INR >1.5 associated with increased mortality 2
• Patients with cardiovascular disease: Consider higher hemoglobin targets (≥10 g/dL) 2