Gastric dumping syndrome

Gastric dumping syndrome, or rapid gastric emptying is a condition where ingested foods bypass the stomach too rapidly and enter the small intestine largely undigested. It happens when the upper end of the small intestine, the duodenum, expands too quickly due to the presence of hyperosmolar (substances with increased osmolarity) food from the stomach. "Early" dumping begins concurrently or immediately succeeding a meal. Symptoms of early dumping include nausea, vomiting, bloating, cramping, diarrhea, dizziness and fatigue. "Late" dumping happens 1 to 3 hours after eating. Symptoms of late dumping include weakness, sweating, and dizziness. Many people have both types. The syndrome is most often associated with gastric surgery.

It is speculated that "early" dumping is associated with difficulty digesting fats while "late" dumping is associated with carbohydrates.

Rapid loading of the small intestine with hypertonic stomach contents can lead to rapid entry of water into the intestinal lumen. Osmotic diarrhea, distension of the small bowel (leading to crampy abdominal pain), and hypovolemia can result.

In addition, people with this syndrome often suffer from low blood sugar, or hypoglycemia, because the rapid "dumping" of food triggers the pancreas to release excessive amounts of insulin into the bloodstream. This type of hypoglycemia is referred to as "alimentary hypoglycemia".

Diagnosis

Physicians diagnose dumping syndrome primarily on the basis of symptoms in patients who have had gastric surgery. Tests may be needed to exclude other conditions that have similar symptoms. Two ways of determining if a patient has dumping syndrome include Barium fluoroscopy and radionuclide scintigraphy.

In the first procedure, a contrast of barium-labeled medium is ingested, and x-ray images are taken; early dumping can be easily recognized by premature emptying of the contrast medium from the stomach.

The second method, scintigraphy (or radionuclide scanning), involves a similar procedure in which a labeled medium containing ^99mTc (or other radionuclide) colloid or chelate is ingested. The ^99mTc isotope decays in the stomach, and the gamma photons emitted are detected by a gamma camera; the radioactivity of the area of interest (the stomach) can then be plotted against time on a graph. Patients with dumping syndrome generally exhibit steep drops in their activity plots, corresponding to abnormally rapid emptying of gastric contents into the duodenum.

Treatment

Dumping syndrome is largely avoidable by avoiding certain foods that are likely to cause it, therefore having a balanced diet is important. Treatment includes changes in eating habits and medication. People who have gastric dumping syndrome need to eat several small meals a day that are low in carbohydrates, avoiding simple sugars, and should drink liquids between meals, not with them. Fiber delays gastric emptying and reduces insulin peaks. People with severe cases take medicine such as octreotide, cholestyramine or proton pump inhibitors (such as pantoprazole) to slow their digestion. Doctors may also recommend surgery. Surgical intervention may include conversion of a Billroth II to a Roux-en Y gastrojejunostomy.

Source

Most of the text of this article is taken from http://digestive.niddk.nih.gov/ddiseases/pubs/rapidgastricemptying/index.htm