Initial Approach to Rectal Bleeding in the Emergency Department
The initial approach to a patient with rectal bleeding in the ED should include immediate assessment of hemodynamic stability, focused history and physical examination including digital rectal examination, laboratory testing, and appropriate endoscopic evaluation based on severity of bleeding. 1
Initial Assessment and Stabilization
Hemodynamic Assessment
- Check vital signs immediately:
- Systolic blood pressure (target >115 mmHg)
- Heart rate (tachycardia >120 bpm indicates significant blood loss)
- Respiratory rate and oxygen saturation
- Signs of shock require immediate resuscitation before diagnostic workup
Laboratory Investigations
- Complete blood count with hemoglobin and hematocrit
- Coagulation profile (PT/INR, PTT)
- Blood typing and cross-matching if severe bleeding
- Target hemoglobin level of at least >7 g/dL during resuscitation 1
Resuscitation (if unstable)
- Establish large-bore IV access (two lines if severe bleeding)
- Crystalloid fluid resuscitation
- Blood transfusion if hemoglobin <7 g/dL
- Avoid fluid overload which may exacerbate bleeding
- Correct any coagulopathy
Diagnostic Evaluation
Focused History
- Characteristics of bleeding:
- Onset, duration, frequency
- Color (bright red vs. maroon vs. melena)
- Volume of blood
- Associated symptoms:
- Abdominal pain, change in bowel habits
- Weight loss, fatigue
- Risk factors for colorectal cancer:
- Age >50 years
- Family history
- Personal history of polyps or inflammatory bowel disease
- Medication history:
- Anticoagulants (significantly increases risk)
- NSAIDs, aspirin
- Recent antibiotic use
Physical Examination
- Abdominal examination
- Digital rectal examination is mandatory to:
- Identify anorectal source of bleeding
- Assess for masses, hemorrhoids, fissures
- Check stool color and presence of blood
Endoscopic Evaluation
First-Line Diagnostic Tools
- Anoscopy or proctoscopy for visualization of anorectal area
- Flexible sigmoidoscopy for more proximal assessment
Urgent Colonoscopy Indications
- High-risk features or ongoing bleeding: perform within 24 hours
- Risk factors for colorectal cancer
- Suspicion of proximal source of bleeding
- Consider upper endoscopy if lower source not identified (up to 15% of serious hematochezia has upper GI source) 1
Risk Stratification
Low-Risk Patients (can potentially avoid admission)
- Hemoglobin >13 g/dL
- Systolic blood pressure >115 mmHg
- Not on anticoagulation therapy 2
High-Risk Patients (require admission)
- Hemodynamic instability
- Significant drop in hemoglobin
- Active bleeding
- Anticoagulant use
- Comorbidities that increase bleeding risk
Common Pitfalls to Avoid
- Failure to perform digital rectal examination - essential for identifying anorectal causes
- Incomplete risk factor assessment - documentation of colorectal cancer risk factors is often suboptimal (9-66% of cases) 3
- Delayed colonoscopy - only 56% of patients who need colonoscopy complete it within a year 3
- Missing upper GI sources - up to 15% of serious hematochezia cases have upper GI sources 1
- Inadequate resuscitation - hemodynamic stabilization must precede diagnostic procedures
- Overaggressive fluid resuscitation - can increase portal pressure and worsen bleeding in cases of varices
Special Considerations
Anorectal Varices
- Consider in patients with portal hypertension or liver disease
- May require specialized management including:
- Endoscopic band ligation
- Sclerotherapy
- Vasoactive medications (terlipressin, octreotide)
- Prophylactic antibiotics 1
Elderly Patients
- Lower threshold for admission and urgent colonoscopy
- Higher risk of significant pathology including colorectal cancer
- More likely to have comorbidities that complicate management
By following this systematic approach, emergency physicians can effectively manage patients with rectal bleeding while minimizing morbidity and mortality through appropriate risk stratification, timely intervention, and diagnostic evaluation.