HIGHLIGHTS FROM MEDICAL GRAND ROUNDS

EDY E. SOFFER, MD Dr. Soffer is a member of the Department of Gastroenterology at the Cleveland Clinic. His major clinical and research interests are in the Gastric and intestinal area of motor dysfunction of the , small bowel, and colon dysmotility syndromes

isorders of motility of the stomach and Causes of are common, and Gastroparesis can be a feature of many disor- patients often present with a variety of ders and syndromes, such as collagen vascular nonspecific symptoms, including nau- diseases and metabolic and endocrine disor- sea, abdominal pain, bloating, and ders, and an effect of medications such as anti- Dvomiting. The challenge for the internist is cholinergics or narcotics. However, most cases determine the nature and extent of motility encountered in clinical practice arc caused by dysfunction. , diabetes, or unknown factors. Vagotomy. Postsurgical gastroparesis GASTRIC DYSMOTILITY occurs less frequently now that antibiotic Rule out treatment for infection and mechanical Gastric motor dysfunction comprises two main potent acid-suppressing medicines have obstruction disorders: accelerated and delayed gastric emp- replaced surgery for treating peptic ulcer. Most before tying. patients who undergo a vagotomy and a Accelerated gastric emptying is seen pyloroplasty or gastroenterostomy experience considering a almost without exception after gastric surgery, little alteration in gastric emptying of solids, diagnosis of specifically vagotomy and drainage procedures although the initial phase of liquid emptying gastroparesis that result in dumping. Typical symptoms can be accelerated, resulting in dumping. occur after meals and include nausea, bloating, Fewer than 3% of postgastrectomy patients pain, diarrhea, and vasomotor symptoms such experience clinically significant gastroparesis. as syncope, flushing, and palpitations. Diabetic gastroparesis. Altered gastroin- Most office-based internists are more like- testinal function is common among patients ly to encounter delayed gastric emptying (also with longstanding type 1 diabetes mellitus, par- known as gastroparesis). Typical symptoms of ticularly those with complications such as gastroparesis include early satiety, nausea and retinopathy, peripheral neuropathy, or vomiting (mostly postprandial), abdominal nephropathy. Delayed emptying of solids is pain, and weight loss. Individually, none of common in diabetic patients and is frequently these symptoms indicates delayed gastric emp- asymptomatic. tying, but when they occur together, the like- Among symptomatic patients, gastroparesis lihood of gastroparesis is strong. frequently runs a fluctuating course, with However, before one considers a diagnosis episodes of pronounced symptoms interspersed of gastroparesis, mechanical obstruction must with relatively symptom-free intervals. be ruled out. Benign or malignant pancreatic Detecting gastroparesis is especially important disease or mesenteric ischemia should be sus- in patients with diabetes because it interferes pected if weight loss and pain are the predom- with nutrient delivery to the small intestine and inant symptoms. can result in fluctuating blood glucose levels.

CLEVELAND CLINIC JOURNAL OF MEDICINE VOLUME 64 • NUMBER 2 FEBRUARY 1997 6 9 Downloaded from www.ccjm.org on October 2, 2021. For personal use only. All other uses require permission. HIGHLIGHTS FROM MEDICAL GRAND ROUNDS n

Gastric motor abnormalities in diabetes nondigestable food from emptying, and can include loss or disruption of antral migrating result in bezoar formation. motor complex (MMC) activity, fasting and postprandial antral hypomotility, and abnor- Pharmacologic therapy malities of the proximal small intestine. The Available agents that stimulate gastric empty- etiology of gut dysmotility in diabetes is not ing are not ideal, because they have an incon- clear, but evidence exists for autonomic ner- sistent effect on the motor function of the vous system and enteric nervous system dys- stomach. The ideal prokinetic agent for gas- function, in addition to the metabolic effects troparesis would target the defined pathophys- of hyperglycemia. iology, enhance stomach function (rather than Idiopathic gastroparesis. Many patients contractions), and cause few side effects. with gastroparesis have no primary abnormali- Cisapride is the most commonly used pro- ty. Most are young women. Some of these kinetic agent because of its good safety profile. patients report having a viral-like illness It is usually given at 10 mg four times a day at before the onset of gastric symptoms. Specific least 30 minutes before meals and at bedtime. viral infections, such as cytomegalovirus and Cisapride has a very good safety profile and herpes simplex, are known to cause gastropare- minimal side effects. sis in immunocompromised patients; the gas- Metoclopramide, a dopamine agonist, has troparesis resolves quickly following antiviral efficacy equal to that of cisapride. However, up therapy. to 20% of patients have side effects, the most troubling of which are related to extrapyrami- Diagnosis dal manifestations and mood changes. The most important diagnostic step for a Erythromycin is not particularly effective Gastroparesis in patient who presents with nausea, vomiting, as a prokinetic agent when given in oral form. diabetic patients bloating, or postprandial abdominal pain is to Cholinergic agents are rarely used because interferes with rule out mechanical obstruction, either of the of their high incidence of side effects. nutrient delivery stomach or the small intestine. After mechan- If tolerance develops to one of these pro- and can result in ical obstruction has been ruled out, gastric kinetic agents, I would increase the dose or add motor function is best evaluated by a another prokinetic agent. fluctuating radioscintigraphic solid-emptying study. This blood glucose test, in which the patient consumes a meal Surgical therapy levels that contains a radioisotope, allows for a sim- If dietary and pharmacologic methods fail in ple, sensitive, quantitative, noninvasive mea- patients with medical causes of gastroparesis, a sure of solid-phase emptying. feeding may be attempted. Subtotal and Roux-en-Y gas- TREATMENT OF GASTRIC DYSMOTILITY trojejunostomy can be helpful in severe post- surgical cases of gastroparesis, but are not effec- Dietary changes tive in cases caused by medical diseases. If radioscintigraphy reveals delayed gastric Gastric pacing, which requires the place- emptying, the initial phase of treatment ment of stimulating electrodes on the stom- should be directed toward dietary changes. ach, is experimental and its value has yet to be Small, frequent meals, preferably in liq- established. uid form, are encouraged because gastric emp- tying is volume-dependent, and liquids empty • INTESTINAL DYSMOTILITY faster than solids. A low-fat diet is helpful because fat is the Small-bowel motor activity and its control most potent inhibitor of gastric emptying. mechanisms are quite similar to those of the A low'residue diet is also important antrum of the stomach. Normal small bowel because the disturbed motor activity prevents motility serves to mix nutrients with digestive

70 CLEVELAND CLINIC JOURNAL OF MEDICINE VOLUME 64 • NUMBER 2 FEBRUARY 1997 Downloaded from www.ccjm.org on October 2, 2021. For personal use only. All other uses require permission. enzymes, allows sufficient time for absorption, general, prokinetic agents are less effective in and propels undigestible parts of the chyme treating intestinal dysmotility than in gastro- distally to the colon. Symptoms of intestinal paresis. dysmotility can be quite similar to those of gas- In refractory or severe, intermittent troparesis, though abdominal distention and intestinal dysmotility, a venting jejunostomy is changes in bowel habits indicate small-bowel helpful. Every attempt should be made to use disease. The disease is typically chronic. the small bowel by infusion of liquid formulas including elemental preparations. Total par- Diagnosis enteral nutrition may be required with bowel There is no adequate functional study of the failure. Intestinal transplantation and pacing small bowel that is analogous to solid phase are still experimental. • gastric emptying studies of the stomach. A diagnosis of intestinal dysmotility must rely on • SUGGESTED READING symptoms, plain abdominal radiographs, bari- um studies, and intestinal manometry. As in Anuras S. Intestinal pseudoobstruction syndrome. Annu Rev Med 1988; 39:1-15. gastric dysmotility, mechanical obstruction should be ruled out in the evaluation of Chaudhuri TK, Fink S. Update: pharmaceuticals and gastric emptying. Am J Gastroenterol 1980; 85:223-230. patients with symptoms of intestinal dysmotil- ity- Janssens J, PeetersTL, Vantrappen G, et al. Improvement ol gastric emp- Flat abdominal radiographs are not sensi- tying in diabetic gastroparesis by erythromycin. N Engl J Med 1990; 322:1028-1031. tive enough to distinguish obstruction from pseudo-obstruction, and contrast studies may Malagelada JR, Rees WDW, Mazzotta LJ, Go VLW. Gastric motor abnor- be needed to exclude mechanical obstruction. malities in diabetic and postvagotomy gastroparesis: Effect ol meioclo- pramide and bethanechol. Gastroenterology 1980; 78:286-293. If pseudo-obstruction is suspected, I would pro- ceed to manometry. Malmud LS, Fisher RS, Knight LC, Rock E. Scinit¡graphic evaluation ol Manometry. Certain abnormal patterns on gastric emptying. Sem Nucl Med 1982; 12:1 16-126. abdominal manometry (eg, lack of response to Minami H. McCallum RW. The physiology and pathophysiology of gas- food) are consistent with visceral neuropathy. tric emptying in humans. Gastroenterology 1989; 86: 1592-1610. Manometry has particular value in patients with unexplained symptoms and a negative Schuffler MD, Baird HW, Fleming CR, et al. Intestinal pseudoobstruction as the presenting manifestation of small cell carcinoma of the lung. Ann work-up. In such cases, normal findings on Intern Med 1983; 98:129-1 34. manometry help to exclude dysmotility. Soffer EE, Thongsawat S. The clinical value of duodcnal-jcjunal manom- etry: Its usefulness in the diagnosis and management of patients with gas- Treatment trointestinal symptoms. Dig Dis Sci 1996; 41:859-863. Treatment of intestinal dysmotility includes a low-fat diet, antibiotics (cycled to prevent bac- Summers RW, Anuras S, Green J. Jejunal manometry patterns in health, partial intestinal obstruction, and pseudoobstruction. Gastroenterology terial overgrowth), and prokinetic agents. In 1983;85:1290-1300.

CLEVELAND CLINIC JOURNAL OF MEDICINE VOLUME 64 • NUMBER 2 FEBRUARY 1997 1 01 Downloaded from www.ccjm.org on October 2, 2021. For personal use only. All other uses require permission.