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Chapter 18 ♦ Acute Abdominal Surgical Emergencies

II. Lower GI bleed A. All other sources of GI bleeding: Jejunum, ileum, colon, and rectum. B. Common causes: Diverticular hemorrhage and bleeding vascular malformations. C. Less common causes: Malignancy, polyps, hemorrhoids, fissures, ischemic or infectious colitis, Meckel diverticulum, and inflammatory bowel disease.

CUT TO CASEBOOK See NMS Surgery Casebook , 3rd edition, Case 8.33: Massive Lower Gastrointestinal Bleeding

III. Treatment: Requires resuscitation, localization of bleeding source, cessation of immediate hemorrhage, and prevention of future episodes. A. Initial approach: Patients with a GI bleed can present in hemorrhagic shock; treat aggressively with resuscitation and expeditious workup. B. Localization 1. Rectal exam: Essential. 2. NG tube for lavage and aspiration: Can diagnose an upper GI source, but does not rule out an upper GI source if negative. 3. Esophagogastroduodenoscopy (EGD): Can localize and treat or rule out upper GI sources of bleeding. 4. Tagged RBC scan a. Identifies active bleeding by gross location, but will not give specific anatomic location. b. Detect bleeds of 0.5 mL/minute, but requires a delay of up to several hours while the study is performed. c. Tagged cells remain in circulation; if the study is negative and the patient rebleeds, it can be repeated within 24 hours. 5. Angiography a. Can identify the bleeding vessel and potentially embolize to provide treatment. b. Can detect bleeding at a rate of 0.5–1.0 mL/minute. 6. Colonoscopy: Difficult in an unprepped colon full of blood, but with good visualization can be therapeutic with clips, epinephrine injections, and cauterization. C. Nonsurgical treatment: Endoscopy, angiography, and embolization. 1. Vasopressin infusion: Will not stop bleeding but may temporize. 2. Ulcers: proton pump inhibitors and treatment for H. pylori. D. Surgical treatment 1. Indications: Persistent hemorrhagic shock (fails resuscitation) and recurrent bleeding despite maximal therapy; about 10% of upper GI bleeds. 2. Operations a. Gastroduodenostomy: Performed if no lesion has been identified. b. Proximal gastrectomy: Performed if no source is seen.