What is the management and treatment approach for a patient presenting with haematochezia (passage of fresh blood per anus)?

Management of Haematochezia

Begin with immediate hemodynamic resuscitation and risk stratification, followed by urgent colonoscopy within 24 hours for patients requiring hospital admission, as this approach prioritizes mortality reduction and identifies treatable bleeding sources in the majority of cases. 1, 2, 3

Immediate Resuscitation and Stabilization

Hemodynamic assessment takes absolute priority over diagnostic procedures. 1, 3

• Check vital signs immediately including heart rate, blood pressure, and assess for signs of hypovolemia or shock 2, 3
• Establish two large-bore IV lines for rapid fluid and blood product administration if hemodynamically unstable 1, 2, 3
• Begin crystalloid infusion targeting mean arterial pressure >65 mmHg while avoiding fluid overload 1, 2, 3
• Maintain hemoglobin level >7 g/dL during resuscitation 1, 3
• Obtain complete blood count, coagulation parameters, blood urea nitrogen, creatinine, and serum electrolytes 2
• Perform blood typing and cross-matching if there are signs of severe bleeding or hemodynamic instability 2
• Insert urinary catheter to monitor hourly urine output (target >30 mL/hr) in severe cases 1
• Correct any coagulopathy before invasive procedures 1

Critical pitfall: Avoid over-transfusion, which may increase portal pressure and potentially worsen bleeding in patients with portal hypertension 1, 3

Risk Stratification Using Oakland Score

Calculate the Oakland score to determine disposition and urgency of investigation. 2, 3

• Patients scoring >8 points: Admit for inpatient management with urgent colonoscopy within 24 hours 2, 3
• Patients scoring ≤8 points: Can be safely discharged for urgent outpatient colonoscopy within 2 weeks if no other indications for admission 2, 3

Diagnostic Algorithm

Step 1: Exclude Upper GI Source First

In patients with severe haematochezia and hypovolemia, perform upper endoscopy before colonoscopy, as an upper GI source will be found in 10-15% of such patients. 4, 1, 3

• Nasogastric lavage is warranted if there is medium to low suspicion of an upper GI source 4, 1
• If blood, clots, or coffee grounds-appearing material is present in the NG aspirate, upper endoscopy must be performed 4
• In the presence of large-volume upper GI bleeding, provide airway protection by intubating the patient prior to upper endoscopy 4

Step 2: Urgent Colonoscopy After Stabilization

Perform colonoscopy within 24 hours after hemodynamic stabilization as the first-line diagnostic approach. 1, 2, 3

• Ensure thorough bowel preparation with polyethylene glycol solutions to improve mucosal visualization and diagnostic yield 1, 2, 3
• Sulfate-based purge appears safer than saline purge for cleansing the colon of stool, clots, and blood 5
• The diagnostic accuracy of colonoscopy ranges from 72-86% in patients with lower GI bleeding 4
• Colonoscopy is feasible and useful after rapid cleansing even in patients with severe haematochezia 4

Critical pitfall: Inadequate bowel preparation leads to poor visualization during colonoscopy and missed diagnoses 1, 3

Step 3: Alternative Diagnostic Modalities When Colonoscopy is Inconclusive

For hemodynamically unstable patients or those with suspected active bleeding who cannot be adequately stabilized, perform CT angiography first to rapidly localize the bleeding site. 1, 2

If initial colonoscopy is inconclusive:

• If bleeding is suspected around the ileocecal valve: Perform repeat colonoscopy with thorough bowel preparation 1
• If repeat colonoscopy fails: Consider radionuclide imaging with [99Tcm] pertechnetate-labeled red blood cells, which can detect active bleeding at rates of 0.1-0.5 mL/min 1
• Angiography should be performed only after positive scintigraphy or in patients with hemodynamic instability and severe unremitting bleeding 1
• Angiography requires a bleeding rate of at least 1 mL/min for accurate detection of extravasation 1

The diagnostic yield of emergency visceral angiography is only 14% with a complication rate of 9%, making it inferior to colonoscopy but potentially complementary 5

Therapeutic Interventions

Endoscopic hemostasis is the preferred first-line treatment for accessible bleeding sources identified during colonoscopy. 1, 3

• Multiple endoscopic techniques are available including injection therapy, thermal coagulation, and mechanical methods such as clips 1
• Hemostasis via colonoscopy has a definitive role in treating focal colonic lesions such as bleeding angiomata 5
• 39% of patients with severe hematochezia require therapeutic endoscopy, 24% require surgery, and 1% require therapeutic angiography 5

Special Therapeutic Considerations by Etiology

For radiation proctitis causing bleeding: Consider formalin application (3.6-4% solution for irrigation or 4-10% on gauze for direct application) or sucralfate enemas 4, 1

For anorectal varices with mild bleeding: Focus on optimal medication for portal hypertension with supportive care 1, 3

• Use vasoactive drugs such as terlipressin or octreotide to reduce splanchnic blood flow and portal pressure 3
• Consider percutaneous transjugular intrahepatic portosystemic shunt (TIPS) to decompress the portal venous system in patients with severe portal hypertension if not contraindicated 3

For angiodysplasia: Recognize these lesions by their characteristic appearance as red, fern-like flat lesions consisting of ectatic blood vessels with diameter of 2-10 mm, most commonly in cecum and proximal ascending colon 4, 1

Common Causes and Clinical Context

• Diverticular bleeding is the most common cause of lower GI bleeding in adults 1
• Approximately 75% of episodes of acute lower GI bleeding due to diverticulosis stop spontaneously 1

• 75% of diverticula are found in the left colon, but when colonoscopy diagnoses diverticular bleeding, 60% is from the left colon versus right colon predominance on angiography, reflecting differences in diagnostic sensitivity 4

• Angiodysplasia is most common in cecum and proximal ascending colon 4, 1
• Inflammatory bowel disease and other forms of colitis can cause haematochezia 4

Medication Management During Acute Bleeding

• Consider temporarily discontinuing antiplatelet agents during acute bleeding episodes 1, 3
• Management of antiplatelet agents and anticoagulants requires a multidisciplinary and individualized approach 3

Critical Pitfalls to Avoid

• Delaying resuscitation to perform diagnostic procedures: Stabilization takes priority over diagnosis 1, 3
• Assuming lower GI source in severe bleeding: Always consider upper GI source, especially with hemodynamic instability 4, 1, 3
• Premature resort to surgery: Attempt to localize bleeding through radiological and/or endoscopic modalities first 1, 3
• Inadequate bowel preparation: This leads to poor visualization and missed diagnoses 1, 2, 3
• Over-transfusion: May increase portal pressure and worsen bleeding in patients with portal hypertension 1, 3