What is the initial management and treatment approach for a patient presenting with lower gastrointestinal (GI) bleeding?

Initial Management of Lower Gastrointestinal Bleeding

The initial management of lower gastrointestinal bleeding (LGIB) should begin with stratification of patients as hemodynamically unstable (shock index >1) or stable, followed by risk assessment using the Oakland score to determine appropriate care setting and investigations. 1, 2, 3

Initial Assessment and Risk Stratification

• All patients presenting with LGIB should have their hemodynamic status assessed using shock index (heart rate/systolic BP), with a shock index >1 indicating instability 1, 3
• For hemodynamically stable patients, calculate the Oakland score to guide management decisions 1, 2
• The Oakland score includes age, gender, previous LGIB admission, digital rectal examination findings, heart rate, systolic blood pressure, and hemoglobin level 1, 2
• Patients with an Oakland score ≤8 points can be safely discharged for urgent outpatient investigation 1, 3
• Patients with an Oakland score >8 points should be admitted to hospital for colonoscopy 1, 3

Management of Hemodynamically Unstable Patients

• For hemodynamically unstable patients (shock index >1) or those with suspected active bleeding, CT angiography (CTA) should be performed immediately as it provides the fastest and least invasive means to localize bleeding 1
• If no source is identified on CTA, upper endoscopy should be performed immediately as LGIB with hemodynamic instability may be indicative of an upper GI bleeding source 1, 4
• Following positive CTA, catheter angiography with embolization should be performed as soon as possible to maximize chances of success (within 60 minutes for hemodynamically unstable patients in centers with 24/7 interventional radiology) 1
• Emergency laparotomy should only be considered after exhausting radiological and endoscopic modalities to localize bleeding, except in exceptional circumstances 1

Transfusion Management

• For clinically stable patients requiring red blood cell transfusion:
  • Use restrictive transfusion thresholds (Hb trigger 70 g/L, target 70-90 g/L) for patients without cardiovascular disease 1, 4
  • For patients with cardiovascular disease, use a higher threshold (Hb trigger 80 g/L, target 100 g/L) 1, 4

Anticoagulation Management

• For patients on warfarin:
  • Interrupt warfarin therapy at presentation 1, 4
  • For unstable gastrointestinal hemorrhage, reverse anticoagulation with prothrombin complex concentrate and vitamin K 1
  • For patients with low thrombotic risk, restart warfarin 7 days after hemorrhage 1
  • For patients with high thrombotic risk (e.g., prosthetic metal heart valve in mitral position), consider low molecular weight heparin 48 hours after hemorrhage 1

Antiplatelet Management

• For patients on aspirin:
  • Aspirin for primary prophylaxis should be permanently discontinued 1
  • Aspirin for secondary prevention should not be routinely stopped; if stopped, restart as soon as hemostasis is achieved 1, 4
• For patients on dual antiplatelet therapy, cardiology consultation should be obtained before discontinuation 4

Common Pitfalls and Caveats

• Failure to consider an upper GI source in patients with hemodynamic instability can lead to delayed diagnosis and treatment 1
• Liberal use of blood transfusion may worsen outcomes; adhere to restrictive transfusion strategies 1, 4
• The Oakland score may underestimate the number of patients who can be safely discharged due to liberal transfusion practices in the derivation population 1, 2
• Mortality in LGIB is generally related to comorbidity rather than exsanguination, with in-hospital mortality of 3.4% overall but rising to 18% for inpatient-onset LGIB and 20% for patients requiring ≥4 units of red cells 1