How to manage a patient with bright red, bloody stools at a General Practitioner (GP) level?

Management of Bright Red Rectal Bleeding at the GP Level

For a patient presenting with bright red rectal bleeding in primary care, immediately assess hemodynamic stability using shock index (heart rate divided by systolic blood pressure), perform a digital rectal examination, and refer urgently to hospital if the shock index is >1 or if there are signs of hemodynamic instability. 1, 2

Immediate Assessment in Primary Care

Vital Signs and Risk Stratification

• Calculate the shock index by dividing heart rate by systolic blood pressure; a value >1 indicates hemodynamic instability requiring immediate hospital referral 1
• Check blood pressure, heart rate, and assess for orthostatic changes (drop in systolic BP >20 mmHg or increase in heart rate >20 bpm when standing) 2
• Obtain hemoglobin/hematocrit levels if point-of-care testing is available to assess severity 2, 3

Critical History Elements

• Duration and frequency: Recent onset with multiple episodes suggests more serious pathology requiring urgent evaluation 4
• Blood characteristics: Blood mixed within stool (rather than coating it) increases likelihood of proximal colonic lesions 4
• Anticoagulation status: Patients on anticoagulants require immediate hospital assessment even if hemodynamically stable 5
• Prior aortic surgery: Any history of aortic aneurysm repair mandates emergency referral, as this may represent a "herald bleed" from an aortoenteric fistula before catastrophic hemorrhage 6

Physical Examination

• Perform digital rectal examination and anoscopy if available to identify hemorrhoids, fissures, or masses 1, 3
• Critical caveat: Normal rectal examination does NOT exclude significant proximal pathology—52% of patients with normal rectal exams have abnormal colonoscopic findings 7

Disposition Algorithm

Immediate Hospital Referral Required:

• Shock index >1 1
• Hemodynamic instability (hypotension, tachycardia, orthostatic changes) 2
• History of aortic surgery (even if bleeding has stopped) 6
• Active anticoagulation with ongoing bleeding 5
• Signs of upper GI bleeding (hematemesis, melena, or large volume bright red bleeding suggesting brisk upper GI source) 8

Urgent Outpatient Colonoscopy Referral (Within 2 Weeks):

• Hemodynamically stable patients age ≥45 years 3, 4
• Blood mixed within stool rather than just coating it 4
• Multiple bleeding episodes per month 4
• Recent onset of bleeding (shorter duration before presentation) 4
• Risk factors for colorectal neoplasia (family history, prior polyps, inflammatory bowel disease) 3

Conservative Management with Scheduled Colonoscopy:

• Young patients (<45 years) with clear anorectal source (hemorrhoids, fissures) on examination AND blood only coating stool 3
• However: Even when hemorrhoids are identified, colonoscopy is still recommended as 48% of patients will have concomitant findings requiring management 7

Common Pitfalls to Avoid

• Do not assume bright red blood equals distal bleeding: Up to 14% of patients with bright red hematochezia have upper GI sources, particularly from duodenal ulcers, and these patients have higher mortality (13.6% vs 7.5%) 8
• Do not rely on patient-reported blood color: While bright red blood suggests distal bleeding, 20 of 217 patients (9%) with bright red hematochezia had lesions proximal to the reach of flexible sigmoidoscopy, including 8 cancers 9
• Do not attribute bleeding to hemorrhoids without full colonic evaluation: This is the most common error—hemorrhoids are present in many patients but may be incidental findings 3, 7
• Do not use nasogastric tube placement routinely: It does not reliably aid diagnosis, does not affect outcomes, and can cause complications 2

What NOT to Do in Primary Care

The British Society of Gastroenterology guideline explicitly states that "the management of uncomplicated LGIB in primary care is beyond the scope" of their recommendations, emphasizing that most patients require hospital-based evaluation 1. Therefore, GP management should focus on rapid assessment, risk stratification, and appropriate referral rather than attempting definitive diagnosis or treatment in the primary care setting.