By Dr Ananya Mandal, MD
Gastroparesis is a condition that leads to delayed emptying of the stomach’s contents after a meal. Normally the stomach contracts to move the food and its contents down into the small intestine for further digestion. This is controlled by the vagus nerve that controls the movement of food from the stomach through the digestive tract.
When a person develops gastroparesis the vagus nerve may be damaged or not functioning adequately. This leads to malfunctioning of the muscles of the stomach and intestines. This causes a stasis of food in the stomach. The food moves slowly or stops moving through the digestive tract.
Causes of gastroparesis
The commonest cause of gastroparesis is diabetes. Individuals with diabetes suffer from a high blood glucose which in turn causes chemical damage to blood vessels that carry oxygen and nutrients to the nerves. This leads to neuropathy or nerve damage.
Neuropathy may take years of high blood sugar to develop. Over time, high blood glucose can damage the vagus nerve. This leads to gastroparesis.
Sometimes gastroparesis may have no underlying cause. In these cases it is called idiopathic gastroparesis. Other causes of gastroparesis include:
surgical injury or damage to the stomach or vagus nerve
some medications (like narcotics or anticholinergics)
anorexia nervosa or bulimia
gastroesophageal reflux disease
underactive thyroid function
Symptoms of gastroparesis
One of the common symptoms is heart burn akin to symptoms of gastroesophageal reflux disease. There is upper abdominal pain, nausea, vomiting, rapid feeling of fullness after taking only a small part of the meal, loss of appetite, loss of weight, abdominal bloating, fluctuating blood sugar levels etc. The symptoms are aggravated with intake if high fiber foods.
Complications of gastroparesis
If left untreated the food tends to remain longer in the stomach. This can lead to bacterial overgrowth from the fermentation of food. The food material can also harden to form bezoars. These lead to obstruction in the gut, nausea and severe vomiting and reflux symptoms. Untreated gastroparesis can also worsen diabetes by altering blood sugar levels.
Diagnosis and treatment of gastroparesis
Diagnosis is preceded by a detailed history and physical examination. Complete blood counts and blood biochemistry including chemical and electrolyte levels are next checked.
Imaging tests such as Upper gastrointestinal endoscopy are performed to check for obstruction. This involves passing a long thin tube called an endoscope down to the esophagus. The camera on the tip of the tube shows the pictures of the inner walls of the stomach and gut.
An ultrasound examination and a barium X ray are also often prescribed. Gastroparesis is likely if the x ray shows food in the stomach.
Gastric emptying scintigraphy is yet another test that shows the rate of emptying of the stomach. This test involves eating a bland meal that contains a small amount of a radioactive substance, called radioisotope. The dose of radiation from the radioisotope is not dangerous.
After the meal scans are taken at 1, 2, 3, and 4 hours. The radioisotope shows up the emptying of the stomach. When more than 10 percent of the meal is still in the stomach at 4 hours, the diagnosis of gastroparesis is confirmed.
After ingestion of a meal with an isotope, breath samples are taken to measure the presence of the isotope in carbon dioxide. The results reveal the rate of emptying of the stomach.
SmartPill is an approved diagnostic method by the U.S. Food and Drug Administration (FDA) (in 2006). It is a small device in capsule form that can be swallowed. The device then moves through the gut and collects information that is sent to a small receiver worn around the waist or neck. After a couple of days the capsule passes out in stool. The receiver is analyzed for the information gathered.
Treatment of gastroparesis
Treatment of gastroparesis depends on severity of the symptoms. The condition is usually a long term one and has no set cure.
Some of the medications used help in rapid emptying of the stomach. These are called prokinetic agents. They include Metoclopramide, Erythromycin (an antibiotic that acts as a prokinetic agent) and Domperidone. Drugs may be used to prevent nausea and vomiting as well.
Lifestyle changes like diet changes and regular exercise are advised. Patient is advised six small meals a day instead of three large ones. If less food enters the stomach with each meal, it is less likely that the patient may not feel overtly full.
In more severe cases, a liquid or pureed diet may be prescribed. Sometimes food may be given in liquid form via a feeding tube directly into the intestines (jejunum). This is needed is severe cases.
Gastric Electrical Stimulation is another method for treating gastroparesis. It is a surgically implanted battery-operated device that sends mild electrical pulses to help control nausea and vomiting associated with gastroparesis.
Reviewed by April Cashin-Garbutt, BA Hons (Cantab)