Chapter 37 - Disorders of Gastrointestinal Function

• gastroesophageal reflux is thought to be associated with a weak or incompetent lower esophageal sphincter
• reflux occurs after eating because the gastric volume becomes larger and the weakened sphincter then allows backflow of acid
• the treatment of GERD usually focuses on conservative measures such as the avoidance of positions and conditions that increase gastric reflux
• avoidance of large meals and foods (i.e., caffeine, fats, and chocolate) that reduce lower esophageal sphincter tone is recommended for reflux prevention
• for people with GERD, it is recommended that meals be eaten sitting up and that the recumbent position be avoided for several hours after a meal
• bending for long periods should be avoided in people with GERD because it tends to increase intra-abdominal pressure and cause gastric reflux
• sleeping with the head elevated helps to prevent gastric reflux during the night
• weight loss is recommended for overweight people to decrease reflux flow
• the reflux of gastric contents may also produce respiratory conditions such as wheezing, cough, and hoarseness
• there is considerable evidence linking GERD with bronchial asthma
• the proposed mechanism of reflux-associated respiratory symptoms include microaspiration and macroaspiration of refluxed contents, laryngeal injury, and vagal-mediated bronchospasm
• most cases of peptic ulcer are caused by H. pylori infection
• the second most common cause of peptic ulcer is NSAID and aspirin use
• aspirin appears to be the most ulcerogenic of the NSAIDs
• ulcer development in NSAID users is dose dependent, but some risk occurs even with low-dose daily aspirin
• the pathogenesis of NSAID-induced ulcers is thought to involve mucosal injury and inhibition of prostaglandin synthesis, which thereby decreases the protective mucous barrier
• NSAID-induced gastric injury is often asymptomatic and life-threatening complications can occur without warning
• bleeding from NSAID-induced gastric injury may be sudden, severe, and without warning or it may be insidious, producing only occult blood in the stool
• many persons with bleeding ulcers have no antecedent symptoms or pain; this is particularly true in persons receiving NSAIDs
• BUN is a measure of kidney function
• normally when a person has a GI bleed, the blood is absorbed into the intestine
• as a result of GI bleeding being absorbed into the intestine, the by-products of blood digestion are reabsorbed and this increases BUN despite normal renal function
• an elevation of BUN can be indicative of renal injury or increased workload
• prostaglandins play a protective role at the renal level
• the chronic use of NSAIDs will cause a cumulative effect in regard to prostaglandins and renal function
• IBD is used to designate two related inflammatory intestinal diseases: Crohn disease and ulcerative colitis
• both Crohn's disease and ulcerative colitis produce inflammation of the bowel, lack confirming evidence of a proven causative agent, have a pattern of familial occurrence, and can by accompanied by systemic manifestations
• the causes of Crohn disease are largely unknown, but one of the common beliefs is that genetic factors predispose to some form of autoimmune reaction, possibly triggered by a relatively innocuous environmental agent such as a dietary antigen or microbial agent
• the pathogenesis of Crohn disease involves a failure of immune regulation, genetic predisposition, and an environmental trigger (especially microbial flora)
• the drug infliximab is utilized in the treatment of moderate-to-severe Crohn disease that does not respond to standard therapies
• infliximab is a monoclonal antibody that targets the destruction of TNS, a mediator of the inflammatory response that is known to be important in granulomatous inflammatory processes such as Crohn disease
• prolonged or severe stress predisposes to peptic ulcer disease because of reduced blood flow to the gastric wall and mucous glands
• the most relevant risk factor for the development of PUD is untreated Helicobacter pylori infection
• stools that are more liquid and contain mucus, frank blood, and pus are typical of ulcerative colitis
• a client with long-standing digestive problems is found to have a deficiency in pepsinogen; the client likely has dysfunction involving the parietal cells