Makindo Medical Notes

Related Subjects: |Ulcerative Colitis |Microscopic colitis |Irritable bowel syndrome |Lower Gastrointestinal (Rectal) Bleeding

>PR bleeding within the first 24 hours of hospitalization, accompanied by a haemoglobin drop of at least 2 g/dL and/or the need for at least 2 units of packed red blood cells, requires urgent diagnosis and intervention to control the bleeding.

Initial Management

About Lower GI Bleeding

• Bleeding originates from the gastrointestinal (GI) tract below the Ligament of Treitz.
• In clinical practice, it predominantly affects the colorectal region.
• It is more common in elderly patients and those on anticoagulation therapy.
• If uncertain, upper GI endoscopy (OGD) or capsule endoscopy should be considered.
• Overall mortality rate from colonic bleeding is 2.4-3.9%.

Risk Factors for Severe Bleeding

• Aspirin use
• Two or more comorbid illnesses
• Pulse greater than 100 beats per minute
• Systolic blood pressure <115 mmHg
• Age over 70 years
• Intestinal ischaemia

Causes of Lower GI Bleeding

Clinical Features

• Usually presents with bright red blood. It may be mixed with stool (haematochezia) or appear as melena.
• Painless, severe bleeding with clots is more common with diverticular haemorrhage. Haemorrhoids also bleed painlessly.
• Bloody diarrhoea often occurs with ischaemic and inflammatory colitis.
• Abdominal pain may suggest ischaemic colitis or diverticular disease.
• Cachexia (weight loss) may suggest malignancy as a cause.
• Vascular disease may suggest mesenteric ischaemia.
• PR examination may reveal bleeding, haemorrhoids, or a rectal mass.
• Anal fissures or local ulcers are typically very painful.
• Look for signs of hemodynamic instability (e.g., BP drop, poor capillary refill, hypotension). Resuscitation may be needed.
• A history of an abdominal aortic aneurysm (AAA) may suggest an aortoenteric fistula.

Note: Haematochezia (PR bleeding) associated with hemodynamic instability may be caused by a large upper gastrointestinal (GI) bleeding source. An OGD (EGD) should be performed to assess the upper GI tract.

Investigations

• Perform FBC, U&E, and coagulation profile if coagulopathy is suspected. Group and cross-match if transfusion is needed.
• Colonoscopy is the most comprehensive test and should be performed within 24 hours of presentation after adequate bowel preparation.
• Sigmoidoscopy can be used for distal lesions.
• Proctoscopy is useful for identifying haemorrhoids.
• CT Angiography can help locate the bleeding source in unstable patients and guide embolization or surgical management.
• Radiographic interventions (tagged RBC scintigraphy, CTA, angiography) may be necessary in high-risk patients with ongoing bleeding who cannot tolerate bowel preparation or colonoscopy.

Management

• Follow ABCs, resuscitate with 1 L of normal saline, and transfuse blood as needed. Correct any coagulopathy.
• Inform surgeons early if significant bleeding occurs. An NG tube may help assess upper GI involvement.
• Colonoscopy should be performed within 24 hours, or sooner if possible. It allows diagnosis and treatment of bleeding stigmata and reduces rebleeding rates.
• Unstable patients may require CT Angiography to locate the bleeding source. If no lower GI source is found, OGD may be necessary. Consider transcatheter embolization if a source is identified.
• Surgery should be considered if there is massive or ongoing bleeding (e.g., >4-5 units in 24 hours). Early discussion with the surgical team is crucial.
• Surgery for prevention of recurrent lower GI bleeding should be individualized, and the bleeding source must be carefully localized before resection.

References

• Lower GI Bleeding: Epidemiology and Management
• New ACG Clinical Guideline: Management of Patients with Acute Lower Gastrointestinal Bleeding