What is the workup plan for a patient presenting with bleeding in stool?

Workup Plan for Bleeding in Stool

For patients presenting with bleeding in stool, the initial diagnostic approach should be an upper and lower GI endoscopy after hemodynamic assessment and stabilization. 1

Initial Assessment

1. Hemodynamic Assessment:

   • Calculate shock index (heart rate divided by systolic blood pressure)
   • If shock index >1: immediate resuscitation required 1
   • Assess vital signs, determine hemoglobin/hematocrit, and evaluate coagulation 2

2. Blood Transfusion Strategy:

   • Maintain hemoglobin >7 g/dL for most patients
   • For patients with cardiovascular disease or massive bleeding, maintain hemoglobin >9 g/dL 1, 2

3. Initial Laboratory Tests:

   • Complete blood count
   • Coagulation profile (PT/INR, PTT)
   • Blood typing and cross-matching if severe bleeding 2
   • Basic metabolic panel

Diagnostic Algorithm

For Hemodynamically Stable Patients:

1. Digital Rectal Examination: Mandatory first step to assess color, volume, and characteristics of blood 2

2. Endoscopic Evaluation:

   • Ano-proctoscopy or flexible sigmoidoscopy as first-line diagnostic tool 2
   • Full colonoscopy within 24 hours after adequate bowel preparation 1, 3
   • Upper endoscopy if lower GI source not identified or if suspicion of upper GI bleeding 1

3. If Endoscopy Inconclusive or Not Feasible:

   • CT angiography: Can detect bleeding at rates of 0.3 mL/min 1, 2
   • If CT angiography negative but bleeding persists: Tagged red blood cell scintigraphy 1

For Hemodynamically Unstable Patients:

1. Immediate Resuscitation:

   • Intravenous fluid replacement
   • Blood transfusion to maintain hemoglobin >7-9 g/dL
   • Correction of coagulopathy 2

2. Urgent Diagnostic Procedures:

   • Immediate upper endoscopy to rule out upper GI source 1
   • If negative, proceed to urgent colonoscopy if patient stabilizes 2
   • If patient remains unstable: Proceed directly to CT angiography or angiography 2, 1

Management Based on Findings

1. Endoscopic Therapy:

   • Indicated for active bleeding, visible vessel, or adherent clot 1
   • Options include endoscopic band ligation, sclerotherapy, or clipping 1

2. Radiological Interventions:

   • Transcatheter embolization for ongoing bleeding not controlled by endoscopy 4
   • Highly effective with relatively low rate of rebleeding 1

3. Surgical Intervention:

   • Reserved for cases with persistent hemodynamic instability despite aggressive resuscitation
   • Indicated when requiring >6 units of blood transfusion or recurrence of severe bleeding 1
   • Pre-operative localization of bleeding site is essential for surgical planning 2

Special Considerations

1. Medication Management:

   • Discontinue NSAIDs and anticoagulants if possible 1
   • For patients on antiplatelet therapy for secondary prevention:
     • Resume aspirin as soon as hemostasis is achieved
     • Resume P2Y12 receptor antagonists within 5 days 1

2. Follow-up:

   • Provide iron supplementation for patients discharged with anemia 1
   • Consider age-appropriate cancer screening (colorectal cancer found in 6% of patients with rectal bleeding) 1

3. Common Causes to Consider:

   • Diverticulosis
   • Angiodysplasia
   • Hemorrhoids
   • Ischemic colitis
   • Inflammatory bowel disease
   • Colorectal cancer 1

Pitfalls to Avoid

1. Delaying endoscopy in patients with ongoing bleeding - early endoscopy improves outcomes 3

2. Inadequate bowel preparation before colonoscopy - reduces diagnostic yield significantly 1

3. Failing to consider upper GI source - hematochezia with hemodynamic instability may indicate an upper GI bleeding source 3

4. Premature discharge without identifying bleeding source - recurrence rates are high, especially in diverticular bleeding 5

5. Overlooking medication-related causes - NSAIDs, anticoagulants, and antiplatelets can contribute to or exacerbate bleeding 1

By following this structured approach, the source of bleeding can be identified and appropriate treatment initiated promptly, reducing morbidity and mortality associated with gastrointestinal bleeding.