Gastroparesis is a disorder affecting people with both type 1 and type 2 diabetes in which the stomach takes too long to empty its contents (delayed gastric emptying). The vagus nerve controls the movement of food through the digestive tract. If the vagus nerve is damaged or stops working, the muscles of the stomach and intestines do not work normally, and the movement of food is slowed or stopped.
Just as with other types of neuropathy, diabetes can damage the vagus nerve if blood glucose levels remain high over a long period of time. High blood glucose causes chemical changes in nerves and damages the blood vessels that carry oxygen and nutrients to the nerves.
What are the Symptoms?
Signs and symptoms of gastroparesis include the following:
- Vomiting of undigested food
- Early feeling of fullness when eating
- Weight loss
- Abdominal bloating
- Erratic blood glucose (sugar) levels
- Lack of appetite
- Gastroesophageal reflux
- Spasms of the stomach wall
These symptoms may be mild or severe, depending on the person.
What are the Complications?
Gastroparesis can make diabetes worse by making it more difficult to manage blood glucose. When food that has been delayed in the stomach finally enters the small intestine and is absorbed, blood glucose levels rise.
If food stays too long in the stomach, it can cause problems like bacterial overgrowth because the food has fermented. Also, the food can harden into solid masses called bezoars that may cause nausea, vomiting, and obstruction in the stomach. Bezoars can be dangerous if they block the passage of food into the small intestine.
How is it Diagnosed?
The diagnosis of gastroparesis is confirmed through one or more of the following tests:
- Barium X-ray
After fasting for 12 hours, you will drink a thick liquid containing barium, which covers the inside of the stomach, making it show up on the X-ray. Normally, the stomach will be empty of all food after 12 hours of fasting. If the X-ray shows food in the stomach, gastroparesis is likely. If the X-ray shows an empty stomach, but the doctor still suspects that you have delayed emptying, you may need to repeat the test another day. On any one day, a person with gastroparesis may digest a meal normally, giving a falsely normal test result. If you have diabetes, your doctor may have special instructions about fasting.
- Barium Beefsteak Meal
You will eat a meal that contains barium, which allows the doctor to watch your stomach as it digests the meal. The amount of time it takes for the barium meal to be digested and leave the stomach gives the doctor an idea of how well the stomach is working. This test can help find emptying problems that do not show up on the liquid barium X-ray. In fact, people who have diabetes-related gastroparesis often digest fluid normally, so the barium beefsteak meal can be more useful.
- Radioisotope Gastric-Emptying Scan
You will eat food that contains a radioisotope, a slightly radioactive substance that will show up on the scan. The dose of radiation from the radioisotope is small and not dangerous. After eating, you will lie under a machine that detects the radioisotope and shows an image of the food in the stomach and how quickly it leaves the stomach. Gastroparesis is diagnosed if more than half of the food remains in the stomach after two hours.
- Gastric Manometry
This test measures electrical and muscular activity in the stomach. The doctor passes a thin tube down the throat into the stomach. The tube contains a wire that takes measurements of the stomach's electrical and muscular activity as it digests liquids and solid food. The measurements show how the stomach is working and whether there is any delay in digestion.
- Blood tests
The doctor may also order laboratory tests to check blood counts and to measure chemical and electrolyte levels.
To rule out causes of gastroparesis other than diabetes, the doctor may do an upper endoscopy or an ultrasound.
- Upper Endoscopy
After giving you a sedative, the doctor passes a long, thin tube called an endoscope through the mouth and gently guides it down the esophagus into the stomach. Through the endoscope, the doctor can look at the lining of the stomach to check for any abnormalities.
To rule out gallbladder disease or pancreatitis as a source of the problem, you may have an ultrasound test, which uses harmless sound waves to outline and define the shape of the gallbladder and pancreas.
How is it Treated?
The most important treatment goal for diabetes-related gastroparesis is to manage your blood glucose levels as well as possible. Treatments include insulin, oral medications, changes in what and when you eat, and, in severe cases, feeding tubes and intravenous feeding.
Insulin for Blood Glucose Control
If you have gastroparesis, your food is being absorbed more slowly and at unpredictable times. To better manage blood glucose, you may need to try the following:
- Take insulin more often
- Take your insulin after you eat instead of before
- Check your blood glucose levels frequently after you eat and administer insulin whenever necessary
Your doctor will give you specific instructions based on your particular needs.
Several drugs are used to treat gastroparesis. Your doctor may try different drugs or combinations of drugs to find the most effective treatment.
Meal and Food Changes
Changing your eating habits can help control gastroparesis. Your doctor or dietitian may give you specific instructions to improve your symptoms. It can be helpful to eat less food at one time. For example, eating six small meals a day instead of three larger meals. Other helpful tips are to eat slowly, sit upright after eating, and take a walk after meals.
The doctor may also recommend that you avoid high-fat and high-fiber foods. Fat naturally slows digestion which can further slow down digestion. Fiber can be difficult to digest and it may be possible that the undigested fiber can form bezoars. Depending on the severity, your doctor may want you to try liquid meals or may prescribe medications to help speed up your digestion.
If other approaches do not work, you may need surgery to insert a feeding tube. The tube, called a jejunostomy tube, is inserted through the skin on your abdomen into the small intestine. The feeding tube allows you to put nutrients directly into the small intestine, bypassing the stomach altogether. You will receive special liquid food to use with the tube. A jejunostomy is particularly useful when gastroparesis prevents the nutrients and medication necessary to regulate blood glucose levels from reaching the bloodstream.
By avoiding the source of the problem (the stomach) and putting nutrients and medication directly into the small intestine, you ensure that these products are digested and delivered to your bloodstream quickly. A jejunostomy tube can be temporary and is used only if necessary when gastroparesis is severe.
It is important to note that in most cases treatment does not cure gastroparesis — it is usually a chronic condition. Treatment helps you manage gastroparesis, so that you can be as healthy and comfortable as possible.