呕血与便血Hematemesis and Hematochezia,Definition,Hematemesis :Bloody vomitus from the upper gastro-intestinal(GI) tract（before the ligament of Treitz) Hematochezia: bright red , maroon or black blood from the rectum,Treitz: The ligament of Treitz is an anatomic landmark for the duodenal-jejunal junction,Patients manifest blood loss,(A) Hematemesis 呕 血 Character Bloody vomitus, either fresh and bright red or older and “coffee -ground” (hematin 酸化正铁血红素),Manner of bleeding presentation,from the GI tract in five ways:,cause of disease,90% upper GI bleeding is due to four lesions: 1) peptic ulcer (消化性溃疡) 2) esophageal or gastric varices (食管胃底静脉曲张破裂) 3) hemorrhagic gastritis (急性糜烂性出血性胃炎) 4)gastric cancer,peptic ulcer,hemorrhagic gastritis,esophageal varices,gastric cancer,Other causes of upper GI bleeding,Mallory-Weiss tear 食道 - 贲门撕裂伤 Foreign body in esophagus 食管异物 Ancylostomiasis 钩虫病 Post-sphincterotomy 括约肌切开术后,Differentiation Nosebleeding? Hemoptysis?,Differntiating hemoptysis and hematemesis,Manner of bleeding presentation,(B)Hematochezia 便 血 Character bright red or maroon blood from the rectum pure blood blood intermixed with formed stool bloody diarrhea,(C) Melena 黑 便 Character Shiny, black, sticky, foul-smelling stool Tarry stool(柏油样便)(degradation of blood) Differentiation exogenous stool darkeners : animal blood, iron , bismuth (铋剂),Manner of bleeding presentation,Manner of bleeding presentation,(D) Stool with occult blood 隐血便 Detected only by testing the stool with a monoclonal antibody for human hemoglobin,Estimate amount of bleeding from upper GI tract,510 ml/d OB + 5070 ml/d Melena 250300 ml in short time Hematemesis,Causes of bleeding,Colorectal cancer Colitis Large hemorrhoid 大痔 Rectum tear 肛裂 Vascular anomalies Hematologic diseases,Manner of bleeding presentation,(E) without any objective sign of bleeding , with symptoms of blood loss,1. Hypovolemia or shock,Depending on speed and volume of blood loss 1000mL: Weakness, giddiness (眩晕), tachycardia(心动过速) , cold extremity, sweating Shock: hypotention (低血压), oliguria, (少尿),2. Anemia and hemogram changing If blood loss is acute, the hematocrit (红细胞比容)dose not change during the first few hours after hemorrhage About 24 to 72 hours later, plasma volume is larger than normal and the hematocrit is at its lowest point,bleeding slowly hypochromic (血红蛋白过少) microcytic (小细胞) red blood cells mean corpuscular volume (MCV， 平均血球压积) of the cells may be low,Hematocrit changes A Before bleeding B Immediately after bleeding C 2472 hours after bleeding,3.Fever,low grade fever in 24 hours after bleeding,4. Azotemia(氮质血症),Degradation of protein in intestinal tract BUN in several hours after bleeding up to the peak in about 24-48 hours normal after 3-4days,5. Bowel sound Active bowel sound usually be presented in acute bleeding from GI tract,Where is the source of bleeding? Localization,Upper GI bleeding: bleeding from a source proximal to the ligament of Treitz Lower GI bleeding: bleeding from a site distal to the ligament of Treitz,Localization,Differentiating features of upper GI and lower GI bleeding Upper GILower GI ManifestationHematemesisHematocheziamelena Nasogastric aspirateBloodyClear BUNElevatedNormal Bowel soundHyperactiveNormal,Upper GI tract bleeding ?,Clinical manifestation (hematemesismelena) Bowel sound Nasogastric tube,Hematemesis,Melena,Hematochezia,More proximal lesions produce hematemesis or melena, whereas more distal lesions are more likely to produce hematochezia,Diagnostic approach,1. History and physical examination 2. Laboratory examination 3. Auxiliary examination,History and physical examination,A history of previously documented GI tract disease determined by radiography, endoscopy, or surgical procedures is very useful,Diagnostic approach to GI bleeding,Diagnostic approach to GI bleeding,A history of epigastric (上腹部) burning pain promptly relieved by food or antacids (抗酸剂) or nocturnal (夜间) pain suggests peptic ulcer disease, particularly duodenal (十二指肠) ulcer,Diagnostic approach to GI bleeding,Patients with stigmata (特征) of hepatitis B or other chronic active liver disease e.g spider angioma (蜘蛛痣), ascites (腹水), gynecomastia (男性乳房发育) may present with painless hematemesis from esophageal varices,Diagnostic approach to GI bleeding,Patients with forceful, retching (干呕)or multiple episodes of vomiting of food prior to the onset of hematemesis may be bleeding from MalloryWeisstears of the gastro-esophageal junction,Diagnostic approach to GI bleeding,A history of gradual weight loss intermittent blood in the stools altered bowel habits often suggests colorectal malignancy,Diagnostic approach to GI bleeding,Hemorrhoidal bleeding is often suggested by the presence of bright red blood surrounding well-formed, normal-appearing stools,Diagnostic approach to GI bleeding,A rectal examination is essential to document stool