What is the initial management for a patient presenting with a per rectal (PR) bleed?

Initial Management of Per Rectal (PR) Bleeding

Begin with immediate hemodynamic assessment and resuscitation, followed by risk stratification using the Oakland score to determine whether the patient requires urgent inpatient colonoscopy within 24 hours or can be safely managed as an outpatient. 1, 2

Immediate Assessment and Resuscitation

Hemodynamic Evaluation

• Check vital signs immediately, including heart rate, blood pressure, and assess for signs of hypovolemia or shock 2
• Establish two large-bore IV lines for rapid fluid and blood product administration if the patient is hemodynamically unstable 1
• Begin crystalloid infusion (normal saline or lactated Ringer's solution) targeting mean arterial pressure >65 mmHg while avoiding fluid overload 1, 3

Laboratory Investigations

• Obtain complete blood count, coagulation parameters (PT/INR, aPTT), 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, 3
• Insert urinary catheter to monitor hourly urine output (target >30 mL/hr) in severe cases 1

Blood Transfusion Strategy

• Maintain hemoglobin level >7 g/dL during resuscitation phase 4, 1
• Avoid over-transfusion, which may increase portal pressure and potentially worsen bleeding in patients with portal hypertension 1
• Correct any coagulopathy before invasive procedures 1, 2

Risk Stratification Using Oakland Score

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

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

This risk stratification tool helps efficiently allocate resources, which is critical given that PR bleeding management is resource-intensive with 19% requiring blood transfusion and 13% requiring diagnostic/therapeutic colonoscopy 5.

Diagnostic Approach

First-Line Diagnostic Testing

Perform colonoscopy within 24 hours after hemodynamic stabilization for major bleeds. 1, 2

• Ensure adequate bowel preparation with polyethylene glycol solutions to improve mucosal visualization and diagnostic yield 1, 3
• Poor bowel preparation is a common pitfall that leads to incomplete evaluation and missed diagnoses 1

Consider Upper GI Source

Perform upper endoscopy first to exclude an upper GI source, particularly if the patient is hemodynamically unstable. 1, 2

• Approximately 10-15% of patients with severe hematochezia have an upper GI source 1
• Even in selected cohorts with diverticulosis and hematochezia, up to 8% of bleedings have an upper source 4

Alternative Diagnostic Modalities for Unstable Patients

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

• CT angiography is preferred over colonoscopy when active bleeding is suspected and the patient cannot be stabilized 1
• If initial colonoscopy is inconclusive, consider radionuclide imaging with technetium-99m-labeled red blood cells, which can detect active bleeding at rates of 0.1-0.5 mL/min 1, 3
• Angiography requires a bleeding rate of at least 1 mL/min for accurate detection and should be performed only after positive scintigraphy or in patients with severe unremitting bleeding 1, 3

Therapeutic Interventions

Endoscopic Management

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

• Multiple endoscopic techniques are available, including injection therapy (epinephrine), thermal coagulation (bipolar electrocoagulation, heater probe), and mechanical methods (clips) 1, 3
• Approximately 75% of episodes of acute lower GI bleeding due to diverticulosis stop spontaneously, but endoscopic therapy should be performed when a bleeding source is identified 1, 3

Special Considerations for Anorectal Varices

In patients with portal hypertension presenting with PR bleeding, suspect anorectal varices and initiate multidisciplinary management early involving hepatology. 4, 6, 2

Mild Bleeding from Anorectal Varices:

• Provide intravenous fluid replacement and blood transfusion if necessary 4, 6
• Correct coagulopathy 4, 6
• Optimize medical management for portal hypertension 4, 6

Severe Bleeding from Anorectal Varices:

• Maintain hemoglobin level >7 g/dL and mean arterial pressure >65 mmHg while avoiding fluid overload 4, 6
• Use vasoactive drugs such as terlipressin or octreotide to reduce splanchnic blood flow and portal pressure 4, 6
• Administer a short course of prophylactic antibiotics 4, 6
• Consider endorectal placement of a compression tube as a bridging maneuver to stabilize the patient or facilitate transfer to a tertiary hospital 4, 6
• Temporarily suspend non-selective beta-adrenergic blockers during acute bleeding (though they are used for prevention/prophylaxis of recurrent variceal bleeding) 4, 6

Step-Up Approach for Refractory Variceal Bleeding:

• Use local endoscopic procedures first (band ligation, sclerotherapy, EUS-guided glue injection) 6
• If medical and local procedures fail, proceed to interventional radiology with embolization for short-term control 4, 6
• Consider percutaneous transjugular intrahepatic portosystemic shunt (TIPS) to decompress the portal venous system in patients with severe portal hypertension if not contraindicated 4, 6
• Reserve surgical procedures only after failure of medical, local, and radiological procedures 4, 6
• Avoid "per anal" suture ligation due to high risk of complications 4, 6

Medication Management

Consider temporarily discontinuing antiplatelet agents during acute bleeding episodes. 1

• Patients on anticoagulants or antiplatelets have higher rates of embolization (28% vs 4%), more packed cell transfusions (2.1 vs 0.7 units), and longer length of stay (7.9 vs 5.7 days) 5
• Management of antiplatelet agents and anticoagulants requires a multidisciplinary and individualized approach 4

Common Pitfalls to Avoid

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