Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Chapter 28 Disorders of Gastrointestinal Function

Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins The Job of the Bowel To digest food: involves a corrosive solution and potentially pathogenic bacteria To absorb the food into the blood while keeping the corrosive substances and the bacteria inside the gut To keep the solution moving down the bowel at the right rate for digestion and absorption

Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Inflammation and Damage to the Bowel Wall Hemorrhage  anemia Perforation  peritonitis Decreased mucosal function  malabsorption Decreased bacterial containment  sepsis

Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Hemorrhage Hemorrhage above the stomach: frank hematemesis Hemorrhage into the stomach with partial digestion of blood: coffee-grounds vomitus Hemorrhage in the intestine with blood mixing into stools: occult blood Hemorrhage into the intestine with large volumes of blood: melena Hemorrhage in the rectum: red blood coating stools

Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins The Vicious Circle: One Kind of Bowel Problem Can Cause Another Inflammation and cell damage Obstruction Malabsorption Reflex paralysis Distension, ischemia Decreased bowel function Food does not pass through bowel at correct rate

Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Question Which symptom accompanies hemorrhage into the stomach? a.Hematemesis b.Occult blood c.Coffee-grounds vomitus d.Melena

Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Answer c.Coffee-grounds vomitus Rationale: Coffee-grounds vomitus is a classic symptom of blood in the stomach (it mixes with chyme to give it the coffee-grounds color and consistency). Hematemesis occurs in hemorrhage above the stomach; occult blood is the result of blood mixing with stool in the small intestine; and melena occurs with large-volume hemorrhages in the intestine.

Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Disorders of the Esophagus Dysphagia Achalasia Esophageal diverticulum Gastroesophageal reflux disease Cancer of the esophagus

Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Disorders of the Stomach Acute gastritis Chronic gastritis Ulcer disease –Peptic ulcer –Zollinger-Ellison syndrome –Stress ulcers Cancer of the stomach

Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Scenario Mrs. D. has pain in her stomach at night and vomits up blood. She is pale and weak The doctor finds that her hematocrit is low Her blood contains large, pale erythrocytes and some reticulocytes Bilirubin levels are normal Question: Explain her symptoms

Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Helicobacter Pylori The major cause of ulcers Second most common cause is NSAIDs H. pylori damages stomach lining ULCER repair and healing increased risk of gastric cancer

Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins “In the US: The frequency of HP infection may be linked to race. White persons account for 29% of cases, and Hispanic persons account for 60% of cases.” “Internationally: … At least half of all people are infected … HP may be detected in approximately 90% of individuals with peptic ulcer disease...” (Santacroce, L., and Miragliotta, G Helicobacter pylori infection. eMedicine. Retrieved April 2005 from

Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Inflammations of the Small and Large Intestines Infectious enterocolitis –Viral infections –Bacterial infections Inflammatory bowel disease –Crohn disease –Ulcerative colitis Diverticular disease Appendicitis

Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Discussion Think back to the last time you had enterocolitis. Questions: List the things that happened to you Which of them were systemic signs of inflammation? Which of them were caused by your sympathetic system? Which of them helped you get over the disease? Which of them could have caused serious complications? Why?

Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Question Which intestinal disorder is an autoimmune disease? a.Enterocolitis b.Crohn disease c.Ulcerative colitis d.Diverticulitis

Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Answer b. Crohn disease Rationale: Crohn disease is an autoimmune disorder that affects the mucous membrane lining of the bowel (it gets thicker and doesn’t function as it should), causing chronic malabsorption.

Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Enterocolitis The bowel attempts to get rid of the infectious agent –Exudate to dilute toxins –Hypermotility Vomiting Decreased intestinal function –Food not absorbed ºOsmosis draws water into the bowel ºOsmotic (or explosive) diarrhea

Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Inflammations That Cannot Be Expelled Pain and sympathetic nervous stimulation cause the bowel to freeze in position –Reflex paralysis or paralytic ileus Muscles of the abdominal wall tighten to protect the inflamed bowel –Board-like abdomen Diaphragm and accessory breathing muscle movements decrease –Shallow breathing

Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins One Kind of Bowel Problem Can Cause Another Inflammation and cell damage Obstruction Reflex paralysis Distension, ischemia

Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Intestinal Obstruction Mechanical –Severe, colicky pain –Borborygmus –Audible, high-pitched peristalsis; peristaltic rushes –Awareness of intestinal movements Paralytic –Continuous pain –Silent abdomen

Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Vomiting  fluid and electrolyte loss Fluids move into intestinal contents Gas accumulates Distension of bowel Compartment syndrome  ischemia, necrosis Anaerobic bacteria produce endotoxin  toxemia Results of Obstruction

Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Question Tell whether the following statement is true or false. Paralytic intestinal obstruction causes audible paralysis.

Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Answer False Rationale: Mechanical obstruction results in high-pitched peristalsis (bowel sounds); in paralytic obstruction, bowel sounds are inaudible (silent abdomen).

Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Bowel Distension and Compartment Syndrome The blood vessels on the surface of the gut are covered and held in place by the inflexible mesentery When the gut lumen distends, it crushes the blood vessels between the gut wall and the mesentery

Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Compartment Syndrome An organ expands inside a membrane that will not expand The blood vessels feeding the organ are crushed between the organ and the membrane Blood supply is cut off

Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Scenario Mrs. K. presents with acute abdominal pain. She has a distended, board-like abdomen with no bowel sounds. Blood pressure is low and heart rate elevated. Her skin is pale and cool with cold sweat. She is very restless and complains of acute abdominal pain. The pain came on over the last 8 hours. WBC count is elevated. Now she complains of nausea and begins throwing up, but there is no blood in her vomitus. She has had no bowel movements or urine production. Question: What adaptive responses and counterattacks are evident?

Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Scenario (cont.) Mrs. K. has begun to run a fever Her skin is now flushed and warm, and her abdomen is further distended Her blood pressure has decreased further The doctor has ordered nasogastric suction and an isotonic IV Question: Why are you taking fluids out of her GI tract and putting them into her veins?

Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Alterations in Intestinal Absorption Malabsorption syndrome Celiac disease