NMS. Surgery

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Chapter 18 ♦ Acute Abdominal Surgical Emergencies

6. Partial obstruction a. Allows small or intermittent amounts of matter through; patients may pass small amounts of gas or stool. b. Radiographs: Gas or contrast will be seen passing into the colon. c. Can respond well to conservative management. 7. Intussusception a. Occurs when one segment of bowel folds or telescopes within another segment. b. Can occur spontaneously in pediatric patients, but in adults, the lead point is suspicious for a tumor and must be investigated. 8. Perforating obstruction: Perforation due to proximal bowel overdistention. B. Location 1. Gastric outlet obstruction: Results in early satiety and nonbilious emesis; typically chronic. 2. Small intestinal obstruction: Results in bilious or feculent emesis. 3. Large intestinal obstruction: May not result in emesis until late in its course after the entire proximal small bowel has dilated. C. Causes 1. Adhesions resulting from previous surgery: Most common cause. 2. Malignancy 1. Most common diagnosis with negative past surgical history. 2. Requires removal or bypass and tumor-specific treatment. 3. Hernias: Common source of obstruction. a. Internal hernias: Bowel segment migrates through an internal opening within the abdominal cavity. b. Treatment: Reduction of hernia contents and hernia repair. 4. Less common causes: Congenital lesions (webs, malrotation), inflammatory lesions (Crohn disease, diverticulitis), foreign bodies, radiation, and trauma. TRUSTED SOURCE Society for Academic Emergency Medicine: Clerkship Directors in Emergency Medicine: Small Bowel Obstruction, 2019. Available at: http://www.saem.org/cdem/education/online-education/m4-curriculum/group-m4- gastrointestinal/small-bowel-obstruction II. Functional obstruction: Inability to move intestinal contents, typically due to impaired motility; can be painless until perforation occurs. A. Ileus (paralytic or adynamic): Diffuse intestinal lack of motility. 1. Causes: after surgery, peritoneal irritation, and electrolyte abnormalities. 2. Treatment: Fluid, nutritional support, and electrolyte replacement. B. Colonic pseudo-obstruction (Ogilvie syndrome): Impaired motility of the colon commonly seen after back or hip surgery.