What is the most appropriate next step in management for an unstable patient with severe lower gastrointestinal bleeding and a diffusely tender abdomen, despite blood transfusions?

Management of Unstable Patient with Lower GI Bleeding and Diffusely Tender Abdomen

For an unstable patient with lower GI bleeding and diffusely tender abdomen despite blood transfusions, CT angiography should be performed immediately as the next step in management, not laparotomy. 1

Initial Assessment and Diagnostic Approach

• CT angiography (CTA) provides the fastest and least invasive means to localize the bleeding site before planning further intervention in hemodynamically unstable patients with lower GI bleeding 1
• For patients with shock index >1 (heart rate/systolic BP) and active bleeding, CTA should be performed immediately to guide subsequent management 1, 2
• A diffusely tender abdomen in the setting of lower GI bleeding may indicate ischemic colitis or other serious pathology, but still requires proper localization before surgical intervention 1

Management Algorithm for Unstable Lower GI Bleeding

1. First step: Perform CT angiography to localize the bleeding source 1
2. Second step: Based on CTA findings:
   • If positive: Proceed to catheter angiography with embolization within 60 minutes 1, 2
   • If negative: Consider upper GI endoscopy to rule out an upper source 1, 3
3. Third step: If bleeding persists despite angiographic intervention, consider surgery only after bleeding source is localized 1

Why Laparotomy is Not the First Choice

• Emergency laparotomy should not be performed unless every effort has been made to localize bleeding by radiological and/or endoscopic modalities 1
• Blind segmental resection or emergency subtotal colectomy without localization is associated with high rebleeding rates (up to 33%) and mortality (33-57%) 1
• The overall operative mortality for emergency surgery for lower GI bleeding is approximately 10%, with higher rates in elderly patients 1

Indications for Emergency Surgery

• Surgery should only be considered when:
  • Hemodynamic instability persists despite aggressive resuscitation 1
  • Blood transfusion requirement exceeds 6 units 1
  • Bleeding source has been clearly identified and more conservative therapies have failed 1
  • Patient is an appropriate surgical candidate without contraindications 1

Why FFP and Colonoscopy Are Not Appropriate Initial Steps

• FFP administration (option A) is only indicated for patients on anticoagulants with unstable GI hemorrhage, not as a primary management strategy 1, 2
• Emergency colonoscopy (option D) is challenging in unstable patients with active bleeding and unprepared bowels, and should be performed after stabilization and adequate bowel preparation 1, 4

Why Angiography Without Prior CTA Is Not Optimal

• While angiography with embolization (option B) is an important treatment modality, it should be preceded by CTA to localize the bleeding and guide the intervention 1
• CTA is faster, less invasive, and helps direct subsequent angiographic intervention to the specific bleeding site 1, 2

Common Pitfalls to Avoid

• Failing to consider an upper GI source in patients with hemodynamic instability, even with hematochezia 1, 3
• Proceeding to emergency laparotomy without first attempting to localize the bleeding source 1
• Delaying intervention in unstable patients with ongoing bleeding 2, 4

In this case, the patient's unstable condition with diffusely tender abdomen and fresh blood on rectal examination requires immediate CTA to localize the bleeding source before any definitive intervention can be planned.