Categorize as stable versus unstable using shock index: <1 stable; >1 unstable or suspect active<unk> 
Unstable
Resuscitate, CT angiogram, if CTA does not identify source of<unk> , upper endoscopy if hemodynamic instability 
Consider transfusing pRBCs/platelets for unstable patients or with very low hemoglobin (<7).  with cardiovascular disease use trigger of 8 and target of 10 hemoglobin.
Emergent sigmoidoscopy/colonoscopy (next 24 hours)
Surgery if endoscopy fails or not available
Stable
Calculate risk score to determine disposition
Oakland score
Glasgow-Blatchford score
Resuscitate, CT angiogram, if CTA does not identify source of<unk> , upper endoscopy if hemodynamic instability 
Consider transfusing pRBCs/platelets for unstable patients or with very low hemoglobin (<7).  with cardiovascular disease use trigger of 8 and target of 10 hemoglobin.
Emergent sigmoidoscopy/colonoscopy (next 24 hours)
Surgery if endoscopy fails or not available
Calculate risk score to determine disposition
Oakland score
Glasgow-Blatchford score
Oakland score
Glasgow-Blatchford score
Correct coagulopathy
Vitamin K 10mg IV (best bioavailability in critical patient)
PCC or FFP
Vitamin K 10mg IV (best bioavailability in critical patient)
PCC or FFP
Marathon runners - 16% will have hematochezia within 24-48 hrs of race and 85% will be guaiac positive
Non-actionable unless abdominal pain present
Non-actionable unless abdominal pain present
Lower gastrointestinal bleeding
Upper GI Bleeding
Gastrointestinal bleeding 
Diverticular disease
Colitis
Diverticulosis
Leaking G-tube
Diverticulitis