Dumping Syndrome – Causes, Symptoms, Diagnosis, Treatment and Ongoing care

Basics

Description

Gastrointestinal and vasomotor symptoms resulting from rapid gastric emptying and delivery of large amounts of hyperosmolar content into the small intestine. Usually occurs following gastric and esophageal surgery (gastrectomy, vagotomy, pyloroplasty, esophagectomy, Nissen fundoplication, or gastric bypass procedures).

Epidemiology

• Overall, about 10% of patients following gastric surgery and up to 50% of patients who undergo esophagectomy develop dumping symptoms.
• Predominant age: Middle age to elderly
• Predominant sex: Female > Male

Incidence

• In the US, 0.9% of proximal gastric vagotomy without any drainage procedure; 10–22% truncal vagotomy and drainage. After partial gastrectomy, 14–20% of patients develop symptoms of dumping.
• It is a prominent feature after bariatric surgery. Over 70% of patients that have undergone gastric bypass procedure experience varying degree of dumping symptoms. It is regarded as a beneficial feature of gastric bypass surgery since patients learn to avoid calorie-rich foods and eat small meals.

Risk Factors

Accelerated gastric emptying resulting from gastric surgery is a main risk factor for dumping syndrome. In fact, the severity of dumping syndrome is proportional to the rate of gastric emptying. The common gastric surgical procedures associated with dumping syndrome are:

• Bariatric surgery (i.e., Roux-en-Y gastric bypass)
• Gastric drainage procedures (e.g., pyloroplasty)
• Partial gastrectomy
• Total gastrectomy. Those with pouch formation have significantly less dumping and heartburn (1)[A].
• Esophagectomy
• Antiulcer surgery (e.g., vagotomy)
• Antireflux surgery (e.g., Nissen fundoplication, especially in pediatric patients)

General Prevention

• Dietary modifications (i.e., eating frequent, small, dry meals that contain limited amount of refined carbohydrates; restrict fluids to between meals; avoid milk products and increase protein/fat intake and supplement dietary fibers, etc.)
• Postural changes (i.e., lying supine for 30 minutes after meals)

Etiology

The pathogenesis of dumping syndrome is multifactorial. It includes at least the following interplaying factors:

• Alterations in the storage function of the stomach and/or the pyloric emptying mechanism, leading to rapid delivery of hyperosmolar material into the intestine. This results in fluid shifts from the intravascular compartment into the bowel lumen, leading to rapid small-bowel distention and an increase in the frequency of bowel contractions (early dumping).
• Supraphysiologic release of various GI peptides/vasoactive mediators, leading to paradoxical vasodilation in a relatively volume-contracted state.
• Reactive hypoglycemia secondary to hyperinsulinemia caused by high concentration of carbohydrates in the proximal small intestine and rapid absorption of glucose (late dumping).
• Pancreatic islet cell hyperplasia, rather than late dumping, is thought to be the underlying mechanism for hyperinsulinemic hypoglycemia with nesidioblastosis after gastric bypass.

Commonly Associated Conditions

• Peptic ulcer disease
• Reactive hypoglycemia
• Gastrectomy/vagotomy/pyloroplasty
• Esophagectomy
• After Nissen fundoplication for reflux disease in pediatric population
• After gastric bypass procedure for morbid obesity

Diagnosis

A suggestive symptom profile in a patient who has undergone gastric (including bariatric) or esophageal surgery warrants the investigation for dumping syndrome.

History

• History of gastric procedures
• GI symptoms (in early dumping):
  • Cramping abdominal pain
  • Diarrhea (postprandial)
  • Borborygmi
  • Bloating or epigastric fullness
  • Nausea/vomiting
• Systemic/vasomotor symptoms (both early and late dumping):
  • Palpitations
  • Diaphoresis
  • Faintness, fatigue, and headache
  • Flushing
  • Light-headedness and desire to lie down
  • Confusion and syncope
  • Malnutrition and weight loss
• Early dumping symptoms include gastrointestinal (abdominal pain, nausea, bloating, borborygmi and diarrhea, etc.) and vasomotor (perspiration and facial flushing, a desire to lie down, palpitations, weakness and syncope, etc.) symptoms; late dumping symptoms include perspiration, palpitations, hunger, weakness, confusion and syncope, etc.

Physical Exam

• Diagnosis is mainly based on typical symptoms in patients with history of gastric procedures. A diagnostic scoring system has been developed by Sigstad based on various weighting factors allocated to the symptoms of dumping. A score index >7 is suggestive of dumping syndrome. The score index is very helpful in assessing a response to therapy.
• No physical signs are specific for dumping syndrome.

Diagnostic Tests & Interpretation

Lab

• Postprandial hypoglycemia
• Anemia
• Hypoalbuminemia
• Drugs that may alter lab results: Insulin
• Disorders that may alter lab results: Diabetes mellitus

Imaging

• Upper gastrointestinal series: Barium rapidly emptying from stomach
• Nuclear medicine gastric emptying study
• Endoscopy (to define anatomy and exclude mechanical obstruction)

Diagnostic Procedures/Surgery

• Dumping syndrome is a clinical diagnosis based on typical symptoms in patients who have undergone gastric surgery.
• Oral glucose challenge test (i.e., oral intake of 50 grams of glucose following 10-hour fasting) can elicit typical signs and symptoms in patients with dumping syndrome. A rise in heart rate by 10 beats per minute or more in the first hour is diagnostic.
• Hydrogen breath test after oral ingestion of glucose is also a sensitive test.

Differential Diagnosis

• Mechanical obstruction
• Gastroenteric fistula
• Celiac sprue
• Crohn disease
• Pancreatic exocrine insufficiency
• Neuroendocrine tumors (e.g., carcinoid)
• Irritable bowel syndrome
• Lactose intolerance

Treatment

Dietary modifications are the mainstay of treatment in patients with dumping syndrome. Medical therapy is effective in patients with incapacitating symptoms who fail dietary modifications. Remedial surgery is only considered in patients refractory to medical management.

Medication

First Line

• Octreotide (Sandostatin) 100–500 µg SC b.i.d. Can be very expensive (2)[B]. Patients may have increased steatorrhea during octreotide treatment, and pancreatic enzyme supplement is effective in relieving this symptom.
• Late dumping symptoms can be ameliorated by the α-glucosidase inhibitor acarbose (100–200 mg, PO t.i.d.), which lowers blood glucose by delaying GI absorption of carbohydrates.
• Pectin/guar gum are effective by delaying glucose absorption and prolonging small bowel transit time.

Second Line

Anticholinergics: Results generally are disappointing.

Additional Treatment

General Measures

Most patients can be managed conservatively with dietary modification and medical treatment. Only a small percentage of patients ultimately require surgical intervention.

Additional Therapies

Continuous trophic enteral feeding via a jejunostomy has been reported to be an effective approach in patients refractory to all other treatment measures.

Surgery/Other Procedures

• Remedial surgery only if dietary and medical management unsuccessful and symptoms debilitating; the results are variable and unpredictable. A proper selection of the surgical intervention is very important. Most patients with dumping syndrome as a result of gastric bypass will find that the effects ameliorate with time (>2 years).
• Options of surgery include Roux-en-Y conversion (from Billroth I and II), pyloric reconstruction (for patients who have severe dumping following pyloroplasty), reversed jejunal segment (for patients who failed Roux-en-Y reconstruction), and conversion of Billroth II to Billroth I anastomosis.
• Patients with refractory dumping symptoms after loop gastrojejunostomy may benefit from simple takedown of the anastomosis; conversion to Roux-en-Y gastrojejunostomy is a reasonable option for patients with disabling dumping after distal gastrectomy. Other procedures have been attempted with limited success.
• The syndrome of hyperinsulinemic hypoglycemia with nesidioblastosis (a hyperplasia of islet cells) after Roux-en-Y gastric bypass (>1–2 year post-op) can usually be managed with low-carbohydrate diet and alpha-glucosidase inhibitors. Subtotal or total pancreatectomy (as has been suggested in the literature) is usually unnecessary.

Ongoing Care

Follow-Up Recommendations

Lying supine for 30 minutes after eating or when symptoms occur may reduce the chance of syncope.

Patient Monitoring

Follow to be sure of adequate nutrition.

Diet

• Low-carbohydrate, high-protein diet
• Add dietary fiber.
• Milk or milk products should be avoided.
• Frequent small meals with minimal liquid
• Avoid hyperosmolar liquids.

Patient Education

National Digestive Diseases Information Clearinghouse, Box NDDIC, Bethesda, MD 20892, (301) 468-6344, digestive.niddk.nih.gov

Prognosis

Favorable

Complications

• Hypoglycemia
• Malnutrition and weight loss
• Electrolyte disturbances, including hypokalemia

References

1. Gertler R, Rosenberg R, Feith M, Schuster T, Friess H et al. Pouch vs. no pouch following total gastrectomy: meta-analysis and systematic review. Am J Gastroenterol. 2009;104:2838–51.

2. Ukleja A. Dumping syndrome: pathophysiology and treatment. Nutr Clin Pract. 2005;20:517–25.

3. Gonzalez-Sánchez JA, Corujo-Vázquez O, Sahai-Hernández M. Bariatric surgery patients: reasons to visit emergency department after surgery. Bol Asoc Med P R. 2007;99:279–83.

4. Penning C, Vecht J, Masclee AA. Efficacy of depot long-acting release octreotide therapy in severe dumping syndrome. Aliment Pharmacol Ther.2005;22:963–9.

5. Bouras EP, Scolapio JS. Gastric motility disorders: management that optimizes nutritional status. J Clin Gastroenterol. 2004;38:549–57.

Additional Reading

Tack J, Arts J, Caenepeel P et al. Pathophysiology, diagnosis and management of postoperative dumping syndrome. Nat Rev Gastroenterol Hepatol.2009;6:583–90.

See Also (Topic, Algorithm, Electronic Media Element)

Diarrhea, Chronic; Hypoglycemia, Non-diabetic; Peptic Ulcer Disease

Algorithm: Diarrhea, Chronic

Codes

ICD9

564.2 Postgastric surgery syndromes

Snomed

80193009 Postgastric surgery syndrome (disorder)

Clinical Pearls

• Vagotomy affects gastric emptying through increased gastric tone and decreased receptive relaxation.
• Dumping syndrome is the most common cause for ER presentation after bariatric surgery (3)[B].
• An increase in heart rate of 10 BPM is noted after glucose challenge (50 g oral glucose) in patients with dumping syndrome.
• Depot octreotide has shown some promise as an alternative to standard SC octreotide (4)[B].
• Some side effects of octreotide are gallstones, steatorrhea, and diarrhea (5)