Key Points
- Use the highest‑yield diagnostic test early; do not let testing delay time‑critical therapy.
- Set objective targets and reassess frequently.
- Plan definitive source control or disease‑specific therapy when indicated; document follow‑up and patient education.
Algorithm
- Resuscitate; evaluate for upper source if indicated.
- Prep and perform colonoscopy within 24 h; treat bleeding lesions.
- If persistent/unstable → CTA and IR embolization; surgical consult for refractory cases; plan secondary prevention.
Clinical Synopsis & Reasoning
Hematochezia often from diverticulosis, angiodysplasia, or hemorrhoids. Resuscitate with restrictive transfusion, exclude brisk upper source when indicated, perform colonoscopy within 24 hours after prep; use CT angiography and IR embolization for ongoing massive bleeding.
Treatment Strategy & Disposition
Stabilize ABCs. Initiate guideline‑concordant first‑line therapy with precise dosing and continuous monitoring. Escalate to advanced/procedural interventions based on explicit failure criteria. Define ICU, step‑down, and ward disposition triggers; involve specialty teams early.
Epidemiology / Risk Factors
- Risk varies by comorbidity and precipitants; see citations for condition‑specific data.
Investigations
| Test | Role / Rationale | Typical Findings | Notes |
|---|
| CBC, coagulation tests, type & cross | Resuscitation | Transfusion planning | Restrictive threshold (Hb ~7–8) |
| NG tube/EGD (selected) and BUN/Cr | Source localization | Rule out upper source | Clinical context |
| CT angiography (active bleed) | Localization | Blush/leak | IR planning |
High-Risk & Disposition Triggers
| Trigger | Why it matters | Action |
|---|
| Instability/ongoing hematochezia | High-risk bleed | ICU; urgent colonoscopy/IR |
| Anticoagulation/antiplatelets | Bleed risk | Reversal/resumption plan |
Pharmacology
| Medication/Intervention | Mechanism | Onset | Role in Therapy | Limitations |
|---|
| Bowel prep (4–6 L PEG) then colonoscopy | Diagnosis/therapy | Identifies and treats lesions | — |
| Transfusion/thromboelastography-guided products | Hemostasis | Hours | Correct coagulopathy | — |
| Hold/reverse anticoagulants where appropriate; resume timing plan | Safety | Balance thrombotic risk | Shared decision |
Prognosis / Complications
- Outcome depends on timeliness of diagnosis and definitive therapy; monitor for complications.
Patient Education / Counseling
- Provide red‑flag education, adherence guidance, and explicit return precautions; arrange timely specialty follow‑up.
References
- ACG guideline on lower GI bleeding — Link