Upper vs Lower GI Bleeding: Initial Localization
Ligament of Treitz (end of duodenum / start of jejunum) is the anatomical boundary. UGIB: hematemesis (vomiting blood or coffee-grounds) or melena (black, tarry, foul-smelling stool — indicates blood digested in upper tract). LGIB: hematochezia (bright red blood per rectum or maroon stool). Exception: massive UGIB (>1000 mL) can present with hematochezia as blood passes rapidly. BUN:Creatinine ratio >30: suggests UGIB — digested blood is a protein load absorbed in the upper GI tract → elevated BUN without proportional Cr rise. Initial resuscitation: two large-bore IVs, type & crossmatch, CBC, BMP, coagulation studies, IV PPI (UGIB), IV fluids/pRBCs, Foley, NPO. NGT/lavage: rarely needed — endoscopy is preferred for diagnosis and treatment.
Upper GI Bleeding Causes and Management
Most common UGIB causes: peptic ulcer disease (PUD) — ~40% (most commonly H. pylori or NSAIDs); variceal bleeding (cirrhosis + portal HTN) — ~15%; Mallory-Weiss tear (esophageal mucosal tear from forceful vomiting) — 5–10%; Dieulafoy lesion (exposed submucosal artery with no overlying ulcer — diagnosed on endoscopy); esophagitis; GAVE (gastric antral vascular ectasia — 'watermelon stomach'). PUD bleeding: upper endoscopy (EGD) within 24h — endoscopic hemostasis (clips, cautery, epinephrine injection) for active bleeding or visible vessel. IV PPI (pantoprazole 80mg bolus → infusion) reduces re-bleeding risk. H. pylori testing + eradication. Variceal bleeding: octreotide IV (reduces portal pressure by splanchnic vasoconstriction) + endoscopic band ligation (EVL) of varices; TIPS (transjugular intrahepatic portosystemic shunt) for refractory bleeding; antibiotics (ciprofloxacin or ceftriaxone) to prevent bacterial peritonitis.
Lower GI Bleeding Causes and Management
Most common LGIB causes: diverticulosis — #1 cause of massive LGIB (painless, from vasa recta erosion at diverticular neck; stops spontaneously in 75–80%); internal hemorrhoids — most common cause of minor rectal bleeding in adults (painless; bright red blood coating the stool); angiodysplasia (vascular ectasia, especially right colon; older patients); colorectal cancer (intermittent blood mixed with stool; iron deficiency anemia); ischemic colitis (watershed areas — splenic flexure and rectosigmoid; postoperative or low-flow states); IBD; infectious colitis. Workup: colonoscopy for most stable LGIB. CT angiography (CTA) for active brisk bleeding (can identify source without bowel prep). Tagged RBC nuclear scan for slow/intermittent bleeding. Angiography ± embolization for active arterial bleeding. Resuscitation: pRBCs for significant bleeding, platelet transfusion if <50K + bleeding, reverse anticoagulation.