Gastroparesis is a medical word for stomach paralysis. Although there are many causes of gastroparesis, diabetes is one of the most common. It can affect up to 20 per cent of people who have other diabetes complications. Although researchers continue to study gastroparesis, relatively little is known about why it happens and who gets it. Damage to the nerves of the stomach is thought to play a major role.

How does the stomach work?

The stomach is so much more than a muscular bag! It does a lot of things after food is eaten. When chewed food arrives in the stomach, the pieces are still too big to be absorbed. First, acid and other digestive enzymes are released to tenderize the food. Next, stomach muscles grind it into pieces about one millimetre wide, the size of a grain of sand. After that, food is released into the small intestine in a slow, controlled way so the body can absorb it. The absorption of sugars and starches leads to a predictable rise in blood glucose after a meal.

For someone with diabetes who takes insulin before a meal, it is especially important that the stomach works properly. If it empties too fast, blood glucose rises much higher than it should before the short-acting insulin can start working. If it empties too slowly, there is a risk that the insulin will start working before blood glucose rises. This leads to low blood glucose (hypoglycemia). Both situations can make the person feel ill. Hypoglycemia can be dangerous.

The problem of gastroparesis

Nerve damage in the stomach – a short circuit

People who have had either type 1 or 2 diabetes for a long time can get nerve damage throughout the body. It most commonly affects the nerves of the feet. Damage causes burning, tingling sensations or numbness in hands, arms, feet and legs. Diabetes can also damage the nerves of the stomach. When this happens, the stomach does not work as well. When the damage is severe, the stomach hardly works at all – what we call gastroparesis.

Those with gastroparesis caused by diabetes can have many symptoms related to the stomach. Nausea, vomiting and abdominal pain are usual. It is common to feel too full or be severely bloated soon after a meal. Some describe vomiting food they ate 12 or more hours before.

The pattern and seriousness of symptoms varies greatly over time. Many have bad symptoms lasting for days or weeks, then long stretches when symptoms are manageable. Admission to hospital to control symptoms is often needed. People with severe gastroparesis are often unable to work because of the symptoms.

It is still not known why some people get gastroparesis and others do not. Those who do get it usually have had diabetes for a long time. They may also have other diabetes complications. Although possible, it is rare to develop gastroparesis as a first complication of diabetes.

Testing for gastroparesis

Usually, a doctor specializing in diabetes or the gut will diagnose gastroparesis. Other causes of chronic vomiting or abdominal pain, like a stomach blockage from an ulcer or cancer, must be ruled out. This can be done with an endoscopy test, where a thin tube with a camera on the end is passed through the mouth into the stomach, or with a barium x-ray. With gastroparesis, food may still be seen in the stomach during an endoscopy even though the person has been fasting for eight hours or more.

This disease can cause symptoms over a long period of time. Many other tests, including ultrasound, CT scans and blood tests, may be done to find the cause. Usually other tests do not show anything wrong with the stomach.

Certain medications, such as the narcotic pain medications morphine and oxycodone, can slow down the stomach. These medications may be changed to see if stomach symptoms improve.

The gastric emptying test is the most important in diagnosing gastroparesis. The person eats a meal, usually a scrambled egg that has a small amount of radioactive material mixed into it. The stomach is then scanned at regular times to see how long it takes the food to pass out of the stomach. If stomach emptying is very slow, this helps make a diagnosis.

Solving the gastroparesis problem

Give the stomach a break!

If your stomach is not working very well, make changes to let it do less work. This means switching to smaller meals eaten more often. Eating less dietary fibre may be required. Since the stomach is not able to digest fibre, it can build up into a clump of material like a hairball, called a bezoar. Bezoars occur less often these days, as people usually seek medical help before they form. This is the only time a doctor will ever tell you to eat less fibre!

Changing to a more liquid diet may help too. Liquids pass very easily through the stomach, often by gravity alone. If your diabetes control is suffering because stomach emptying is not predictable, this can be a good strategy.

If gastroparesis is very severe and constant vomiting makes it impossible to keep anything in the stomach, a feeding tube may be needed. The tube can be put into the small intestine through the skin of the belly (called a jejunostomy tube). It may also go through the nose (nasojejunal tube). Some people need to use the tube permanently.

In rare situations, someone whose gut has completely shut down may be fed using intravenous nutrition.

A long time ago, some surgeons would remove the stomach of people with severe gastroparesis. This is no longer an accepted treatment.

If diet does not do it . . .

Medications are the basic support of treatment for gastroparesis. They are often started at the same time as changes to the diet. Three main types of drugs are used:

prokinetics, which speed up stomach emptying
antiemetics, which relieve nausea and vomiting
and pain control medications.

The most common prokinetics used are domperidone (Motilium™) or metoclopramide (Maxeran™). In severe cases, an antibiotic that stimulates the stomach (erythromycin) and other less common drugs may be used. Usually these medications are taken continuously to keep symptoms at bay. A variety of antiemetics and pain medications are available, many familiar and sold over-the-counter. Often more than one medication is necessary to get relief.

When medications fail, a relatively new procedure called gastric electrical stimulation (Enterra™ Therapy) can help. This treatment uses regular electrical pulses, given through small wires sewn into the outside of the stomach. The wires attach to a small battery pack implanted under the skin of the belly. Although this treatment has been called a ‘stomach pacemaker,’ researchers are not entirely sure how it works. It improves symptoms in many people, but it is not a cure.

Enterra™ Therapy is approved for use in gastroparesis patients who have not responded to medications. Unfortunately, no provincial health care plans cover this treatment in Canada at present. Availability is mostly limited to research studies.

Outlook

So how can you prevent gastroparesis? Like other complications of diabetes, the best way to prevent it is keeping your diabetes under good control. Even so, some experience it in spite of their best efforts, perhaps after only a short time with diabetes. Talk to your doctor if problems with nausea, vomiting, or other symptoms from eating will not go away. If gastroparesis is suspected, seeing a gastroenterologist (digestive system specialist) is important.

If you do have gastroparesis, there is hope. Research into this disorder is ongoing in western Canada and around the world. Treatments are improving along with our understanding of this disabling disease. For more information, try the Gastroparesis and Dysmotilities Association, a Canadian-based patient support group. They have an excellent website at www.digestivedistress.com.

Gastroparesis A gut reaction