THE STOMACH, PYLORUS, AND BEYOND!
| HOW TO DIAGNOSE AND TREAT NEUROMUSCULAR DISORDERS OF THE STOMACH —Kenneth L. Koch,
MD, Professor of Internal Medicine, Division of Gastroenterology, Wake Forest University Medical Center, Winston-Salem,
NC
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| Overview of stomach function: vagus nerve relaxes stomach to receive solid food; food then compressed in corpus
and antrum; peristalsis mixes food with acid and pepsin, breaking it down into nutrient suspension (chyme); pancreas releases
cholecystokinin (CCK), and gallbladder releases bile, but relaxation and antral contraction essential; propulsion of
food from antrum into duodenum similar to heart’s pumping of blood (“antral systole”)
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| Electrical activity of stomach
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 | Pacesetter potentials: pacemaker region in antrum, between fundus and greater curvature, area of greatest electrical cycling
in stomach; pacesetter potentials (slow waves) circle around stomach, reaching pylorus in ≈20 sec, then starting
again; normal stomach pacemaker rhythm 3 cycles/min; this rhythmicity not seen in fundus
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| Spike or plateau potentials: necessary for strong contractions of circular muscles that mix and empty intraluminal contents;
mediated by vagus and sympathetic nerves
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| Interstitial cells of Cajal: pacemaker cells of gastrointestinal (GI) tract; near circular muscles
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| Solid-phase gastric emptying study: subject ingests 2 scrambled eggs labeled with technetium, so their journey through
GI tract can be followed; yields data on postprandial neuromuscular activity of stomach
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| Dysmotility-like symptoms: nonspecific; affect ≈20% of population; include early satiety, postprandial fullness, nausea,
or vomiting (regurgitation of chewed or undigested food suggests problem with stomach neuromuscular activity),
and upper abdominal bloating; patients usually feel all right if they do not eat
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| Differential diagnosis: proton pump inhibitors ineffective because symptoms not related to acid; fiber may relieve constipation
and diarrhea of irritable bowel syndrome; prokinetic agents sometimes helpful; “alarm” symptoms include pain,
unintended weight loss, and anemia, especially if patient elderly (indications for more aggressive diagnostic work-up
than empiric trials); if mucosa normal on endoscopy and pancreas and gallbladder normal on ultrasonography, consider
testing for gastric neuromuscular problem
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| Diagnosing nonspecific symptoms: many dyspeptic patients have impaired fundic relaxation; confirm with balloon studies
(fundus does not relax when balloon distends it); antrum dilates in some patients, others have poor contractility or
even gastroparesis (inability to empty labeled eggs within normal time); dysrhythmias—spasms of pylorus; visceral
hypersensitivity (vagal afferent dysfunction)
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| Diagnostic tests: after baseline electrogastrography (EGG), have fasting patient drink water over 5–min period, then
record symptoms and EGG response for 30 min; combine with gastric emptying study for insight into stomach’s electrical
and contractile function; healthy person can drink ≈20 oz (600 mL) of water before feeling full, while dyspeptic
patients can drink 350 to 400 mL; suggests problems with stomach stretching or relaxation
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| Therapeutic approaches: educating patients about nature of condition helps them deal with symptoms
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| Prokinetic agents: metoclopramide (Reglan) relieves nausea and bloating, but associated with depression and parkinsonian
symptoms (frequent drug holidays recommended); erythromycin stimulates antral contractions (indicated for gastroparesis);
tegaserod (Zelnorm) helps gastroparesis and some dyspepsia symptoms (approved for women with constipation and
irritable bowel syndrome); domperidone (obtain from compounding pharmacy or from Canada) dopamine-2 antagonist
without side effects of metoclopramide
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| Stomach pacing: newest approach; pacemakers programmed for gastric stimulation sometimes approved for compassionate
use; patients report 50% to 70% symptom reduction
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| Dyspepsia with normal electrical function: consider extragastric causes (gallbladder, acid reflux, irritable bowel
syndrome, or central nervous system disease [migraine, complex partial seizure]), visceral hypersensitivity, obstruction
(suspect if patient has gastroparesis with normal stomach rhythm)
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| ENTERAL ACCESS BEYOND THE PYLORUS: WHEN AND HOW —Mark A. Schattner, MD, Attending Physician,
Memorial Sloan-Kettering Cancer Center, New York, NY
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| Situations that preclude percutaneous endoscopic gastrostomy (PEG): postgastrectomy; postesophagectomy
and gastric pull-up; gastroparesis; mechanical ventilation; postgastrojejunostomy; mechanical gastric outlet obstruction
that cannot be stented; recurrent aspiration of gastric contents (prevent by placing tube beyond ligament of Treitz); acute
pancreatitis (jejunal feeding support method of choice)
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| Options for gaining jejunal access
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| Nasojejunal tubes: indicated only for short-term use; prone to clogging; good way of testing for tolerance before PEG;
endoscopic placement method of choice
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| Surgical jejunostomy: open or laparoscopic; jejunum fixed to abdominal wall; complications include abdominal torsion
and ischemia; maximum tube size usually 10F; major abdominal operation with significant mortality and morbidity;
consider if other methods fail, or as part of another procedure
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| Jejunal extension through PEG (JET-PEG): create large-bore gastrostomy and endoscopically advance 12F extension
through it, placing tube in jejunum; tip of tube may be drawn back into stomach, leading to complications of inappropriate
stomach feeding (eg, aspiration, intolerance); thus, historical results poor; in comparison study, direct percutaneous
endoscopic jejunostomy (D-PEJ) more stable and reliable than JET-PEG, which required frequent endoscopic
reintervention; indicated for patients in whom direct jejunostomy placement impossible
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| Direct radiographic jejunostomy: requires simultaneous guidance with computed tomography (CT) and fluoroscopy;
however, success rate high in limited series; consider if patient cannot tolerate endoscopy
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| D-PEJ: true jejunostomy (modification of PEG procedure); involves placement of pediatric colonoscope and standard
20F tubes to prevent clogging or migration; cannot use balloon-type internal bumper; mushroom-type bumper necessary
(leaves enough luminal space to prevent obstruction); ensure indentation and transillumination discrete and well-
correlated (may take multiple passes from pylorus to midjejunum); then rapidly insert trocar and grasp thread with biopsy
forceps; tube may remain in unusual locations but work well; advantages—method of choice for durable jejunal
access in difficult patients; can also establish external bypasses to permit oral feeding by patients with nonfunctioning
gastrojejunostomy; procedure of choice for long-term access, especially for patients on mechanical ventilation, or for
complications of esophagectomy; can eliminate need for total parenteral nutrition and facilitate discharge; does not
stimulate pancreatic secretions, allowing organ to rest in cases of pancreatitis; caveat—follow-up by gastroenterologist
or specialized nutrition support team essential
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| PALLIATION OF PANCREATIC MALIGNANCY: ENDOSCOPIST, ONCOLOGIST, SURGEON, OR
EVERYONE? —Michael Kochman, MD, Professor of Medicine and Surgery, Hospital of University of Pennsylvania,
Philadelphia
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| Surgical resection: first choice still Whipple procedure, with some modern modifications (eg, intraprocedural stenting);
goal is to use endoscopic ultrasonography (EUS) and cross-sectional imaging for identification and staging, biopsies,
and prognostication
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| Palliation: relieves pruritus, gastric outlet obstruction, inanition, and weight loss
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| Nutritional supplements: enzymes promote weight gain
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| Imaging: magnetic resonance imaging (MRI) operator-dependent modality that requires reconstruction techniques and
skilled observer; in pancreatic cancer, endoscopic retrograde cholangiopancreatography (ERCP) palliative, not diagnostic;
lesion easy to see on magnetic resonance cholangiopancreatography (MRCP; also demonstrates superior mesenteric
vein [SMV] impingement); controversy over whether SMV and portal vein involvement make patient
unresectable; in tumor, node, metastasis (TNM) staging, only arterial encasement evidence of nonresectability
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| Unpublished data: long-term survival associated with “clean” Whipple procedure (negative margins and lymph nodes)
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| Role of EUS: after its introduction (1993-1996), completed Whipple rate rose from 50% to 70%; clean Whipple rate rose
also; no role for preoperative vascular staging; nodal involvement critical prognostic factor
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| Gemcitabine (Gemzar): standard of care; concurrent irradiation inadvisable due to toxicity; prolongs survival by 8 to 10
mo; radiation does not improve survival, but relieves pain, reducing need for narcotics; gemcitabine effective even
with R1 resection (ie, residual tumor)
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| ERCP: indicated only for palliation or when surgery delayed; should not be used routinely to treat pancreatic carcinoma;
cytology and tissue acquisition—methods include bile cytology (30% sensitivity); brush cytology (sensitivity
≈40%); forceps biopsy; sensitivity 60% with combined techniques; precautions—have clear goals; endoprosthesis indicated
for palliation if patient has symptoms, pruritus, or if surgery delayed; availability of liver sufficient for palliation
also of concern; covered metal endoprosthesis may be acceptable for patients with unknown resectability status
(may be pulled out without duct damage)
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| Tissue harvest: EUS probably single best technique; sensitivity 90% to 95%, even among patients in whom other methods of
cytology have failed; with EUS, can also place celiac block; helps with finding tumor, making diagnosis, and local staging
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| Gastric outlet obstruction: scanning indicated for unresectable lesions; endoprosthetics do not help patients with peritoneal
carcinomatosis; in one retrospective series of patients who received wall stents (2002), average cost ≈$6000 per
patient, compared to $13,000 for surgical palliation; 31 of 36 patients with gastric outlet obstruction required only one
endoprosthetic; 15 of 16 patients with biliary obstruction successfully treated with endoprostheses (before placement
of metal prosthetic); in unrelated study, wall stents associated with good preservation of oral intake; compared to surgery,
endoprosthetics associated with better quality of life
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| Celiac neurolysis: associated with reduced pain scores and less need for narcotics, although papers in anesthesia literature
suggest it offers no benefit
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| Laparoscopic staging: in 1999 study conducted at Memorial-Sloan Kettering, when laparoscopic staging showed patients
to be unresectable, procedure terminated with no double bypass; second intervention rarely needed; in other studies comparing
survival among patients undergoing open, endoscopic, and laparoscopic procedures, findings varied (patients often not
randomized); if patient already has endoscopic stent, is in operating room, and has symptoms, bypass recommended; without
stent, laparoscopy and subsequent palliation recommended
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| Conclusion: surgery indicated mainly to cure localized disease, or for bypass to palliate nonresectable disease; endoscopic
palliation effective; 6% of nonresectable patients have peritoneal studding or liver metastases, but surgeons still
begin with laparoscopy, ending it if necessary, leaving endoscopic palliation to oncologists, and reserving surgery for patients
who fail medical palliation
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| LIVER TRANSPLANT MEDICAL ISSUES —Robert O’Shea, MD, Cleveland Clinic Foundation, Cleveland, OH
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| Questions posed in National Institutes of Health (NIH) consensus statement (1983): are there patients for
whom transplantation appropriate? what is outcome? what principles guide selection and timing of surgery? how should
transplant programs function? what are directions for future research?
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| Patient selection: must determine whether transplantation right for individual patient, whether any other effective therapy
exists, and which candidates appropriate; indications—liver failure; past restrictions related to age, comorbidities,
and HIV status becoming less common; contraindications—active infection outside biliary tree; metastatic cancer; advanced
cardiac or pulmonary disease of nonhepatic origin; and active alcohol or other chemical dependence
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| Etiology of liver failure: hepatitis C primary cause of liver transplantation for past decade; other liver diseases; conditions
that affect quality of life (eg, familial amyloid polyneuropathy or hyperoxaluria)
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| Candidates for transplantation: sickest patients first; most common scoring systems are Child-Turcotte-Pugh score
(use declining), Model for End-Stage Liver Disease (MELD) score, and Kings College criteria
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| MELD score: for chronic liver failure; continuous rather than categorical; derived at Mayo Clinic from patients undergoing
transhepatic intrajugular portosystemic shunt (TIPS) procedures for variceal bleeding or refractory ascites; later extended
to patients with cirrhosis; originally designed to look at 3-mo mortality; now used to predict mortality after
transplant and 1yr before transplant
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| Kings College criteria: used in acute liver failure; divides patients by etiology (acetaminophen or nonacetaminophen)
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| Indications for considering transplantation: when disease’s natural history suggests that survival will be better
with transplantation than without it; according to United Network for Organ Sharing (UNOS), when survival without
transplantation <88% at 1 yr, ≤80% at 3 yr, and ≤75% at 5 yr (Child-Pugh score B or C or MELD score >10); evidence of
decompensation (eg, ascites, bleeding, encephalopathy)
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| Pretransplant evaluation: should include cause and severity of liver disease; liver’s functional capacity; comorbidities;
psychosocial and psychiatric factors; consists of history and physical examination; cardiopulmonary assessment;
laboratory studies, including viral serology; input from specialists in psychiatry, social work, and chemical dependence;
financial counseling important due to prohibitive costs of posttransplant immunosuppression; imaging studies sometimes
necessary; patient’s support, motivation, and willingness to comply with posttransplantation regimen major determinants
of outcome
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Educational Objectives
| The goal of this program is to review selected topics on the management of diseases of the digestive organs. After hearing
and assimilating this program, the listener will be better able to:
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| 1. Describe the electrophysiology of the stomach.
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| 2. Name the various methods of gaining access to the jejunum for feeding.
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| 3. List the options for palliation of pancreatic cancer symptoms.
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| 4. Compare the indications for surgery and medical palliation in patients with pancreatic cancer.
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| 5. Recognize the indications for liver transplantation.
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Discussed on this Program
Amitriptyline HCl [Elavil]
Cisapride [Propulsid]
Dicyclomine HCl [Antispas, Bentyl, Byclomine, Dibent, Dilomine, Di-Spaz, Or-Tyl]
Domperidone [Motilium] (investigational)
Erythromycin [many preparations and trade names]
Fluorouracil (5-fluorouracil, 5-FU) [Adrucil, Carac, Efudex, Fluoroplex]
Gemcitabine HCl [Gemzar]
Metoclopramide [Maxolon, Metoclopramide Intensol, Octamide PFS, Reclamide, Reglan]
Tegaserod maleate [Zelnorm]
Suggested Reading
Artifon EL et al: Surgery or endoscopy for palliation of biliary obstruction due to metastatic pancreatic cancer. Am J
Gastroenterol 101:2031, 2006; Barrera R et al: Outcome of direct percutaneous endoscopic jejunostomy tube placement
for nutritional support in critically ill, mechanically ventilated patients. J Crit Care 16:178, 2001; Fan AC et al:
Comparison of direct percutaneous endoscopic jejunostomy and PEG with jejunal extension. Gastrointest Endosc 56:890,
2002; Fiocca E et al: Palliative treatment of upper gastrointestinal obstruction using self-expandable metal stents. Eur
Rev Med Pharmacol Sci 10:179, 2006; Freeman RB et al: Improving liver allocation: MELD and PELD. Am J Transplant
4 Suppl 9:114, 2004; Kaminski DL et al: Palliation in pancreatic cancer: the controversies continue. Curr Surg
62:19, 2005; Labori KJ et al: Symptom profiles and palliative care in advanced pancreatic cancer—a prospective study.
Support Care Cancer, April, 2006 (Epub ahead of print); Merritt WT: Issues affecting liver transplantation. Best Pract
Res Clin Anaesthesiol 19:17, 2005; National Institutes of Health Development Conference Statement: Liver
Transplantation—June 20-23, 1983. Hepatology 4(1 Suppl):107S, 1984; Rumalla A, Baron TH: Results of direct percutaneous
endoscopic jejunostomy, an alternative method for providing jejunal feeding. Mayo Clin Proc 75:807, 2000; Simon
T, Fink AS: Recent experiences with percutaneous endoscopic gastrostomy/jejunostomy (PEG/J). Surg Endosc
14:436, 2000; Telford JJ et al: Palliation of patients with malignant gastric outlet obstruction with the enteral Wallstent:
outcomes from a multicenter study. Gastrointest Endosc 60:916, 2004; Telford JJ et al: Pancreatic stent placement for
duct disruption. Gastrointest Endosc 56:18, 2002.
Faculty Disclosure
In adherence to ACCME guidelines, the Audio-Digest Foundation requests all lecturers to disclose any significant financial
relationship with the manufacturer or provider of any commercial product or service discussed. The following has been disclosed:
Dr. Koch is an advisor for the Smartpill Corporation.
Dr. Koch spoke at Emerging Diagnostic and Therapeutic Options in Gastrointestinal and Liver Disorders, held October
8, 2005, in Winston-Salem, NC, and sponsored by the Wake Forest University School of Medicine, in partnership
with the Northwest Area Health Education Center. Dr. Schattner was recorded at the 29th Annual New York
Course, held December 14-17, 2005, in New York, NY, and sponsored by the Albert Einstein College of Medicine
and the New York Society of Gastrointestinal Endoscopy. Dr. Kochman made his presentation at the 3rd Annual
UCLA Gastroenterology Symposium, held February 18-19, 2006, in Beverly Hills, CA, and sponsored by the Division
of Digestive Diseases and the Office of Continuing Medical Education, David Geffen School of Medicine, at the
University of California, Los Angeles. Dr. O’Shea spoke at the 41st Annual Gastroenterology Update, held October
6-7, 2005, in Cleveland, OH, and sponsored by the Cleveland Clinic Foundation, Department of Gastroenterology
and Hepatology, in conjunction with the American College of Gastroenterology. The Audio-Digest Foundation
thanks the speakers and the sponsors for their cooperation in the production of this program.
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