Enterra Therapy For Gastroparesis

What is the Enterra Therapy System?

Enterra Therapy is a medical treatment designed to help control chronic nausea and vomiting associated with gastroparesis. Enterra therapy works through what’s known as gastric electrical stimulation (GES). Gastric electrical stimulation involves stimulating the smooth muscles of the lower abdomen with mild electrical pulses.

How does Enterra Therapy Work?

The Enterra Therapy System relies on a small device called a gastric neurostimulator, which is implanted beneath the skin. During the surgical procedure, which is usually performed while the patient is under general anesthesia, two leads consisting of medical-grade insulated wires are also implanted in the wall of the abdomen and are connected to the gastric stimulator. 

Once activated and programmed during a follow-up visit, the two leads connected to the implanted gastric electrical stimulator transmit mild electrical pulses that activate the nerves and smooth muscles of the lower abdominal region.

The electrical stimulation provided by the Enterra Therapy System can help some patients reduce the chronic nausea and vomiting associated with gastroparesis when it can’t be controlled through drugs or other therapies.

Most patients require a combination of Enterra therapy, medication and diet changes to control their symptoms. Once the neurostimulator is implanted, however, it can be adjusted or reprogrammed at follow-up visits without any discomfort or invasive procedures, or even turned off if the patient experiences unpleasant side effects from Enterra therapy.  

What Conditions Does Enterra Therapy Help Treat?

Enterra Therapy is designed to reduce treat diabetic and idiopathic gastroparesis (that is, gastroparesis with no known cause) in adults between 18-70 years of age. Gastroparesis which is a chronic disorder of the GI tract that often causes severe nausea and vomiting.

What is Gastroparesis?

Gastroparesis is a condition in which the stomach cannot fully empty itself of food. Also known as delayed gastric emptying, the condition can lead to serious symptoms, including chronic nausea and vomiting.

When you swallow food, muscle contractions in the stomach normally help break the food down before moving it along to the small intestine, where digestion continues. This process of muscle contractions pushing food through the gastrointestinal tract is know as gastric motility. In many patients with gastroparesis, the muscle contractions that allow gastric motility to occur are weak or don’t happen at all.

That causes food to remain in the stomach much longer than normal, which can contribute to the nausea and vomiting symptoms seen in those with gastroparesis.

What Causes Gastroparesis?

The most common cause of gastroparesis is diabetes. If a person’s blood sugar levels have been elevated or poorly controlled over a long time, that can sometimes cause damage to the vagus nerve, which is a major electrical pathway through the body that controls muscle contractions in the stomach and the small intestine.

However, in some cases, gastroparesis happens for no known reason (AKA idiopathic gastroparesis).

How Rare is Gastroparesis?

Gastroparesis is considered a rare medical condition. For every 100,000 people in the U.S., about 10 men and 40 women have gastroparesis.

What is Medically Refractory Gastroparesis?

Refractory gastroparesis happens when a patient with gastroparesis continues to experience symptoms of the condition like despite attempts to control it through dietary changes and drug therapies. Those with the chronic nausea and vomiting that are characteristic of refractory gastroparesis may be good candidates for Enterra therapy.

What are the Symptoms of Gastroparesis?

While the severity of symptoms ranges from patient to patient, those with diabetic and idiopathic gastroparesis often face health challenges, including nausea and vomiting, malnutrition due to difficulty absorbing nutrients from food and problems controlling their blood sugar. Other symptoms of gastroparesis include:  

  • A feeling of fullness after eating only a small amount of food (AKA early satiety)
  • Severe or recurring nausea and vomiting over a period of months
  • Recurring pain in the lower abdominal region
  • Vomiting undigested food several hours after a meal
  • Vomiting-related dehydration in particularly severe cases
  • Bloating and recurrent belching
  • Heartburn or gastroesophageal reflux disease (GERD)
  • Loss of appetite
  • Unintentional weight loss

Are There Any Side Effects to Enterra Therapy? 

In use in the U.S. since 2000, Enterra therapy is generally considered an effective and safe treatment for chronic nausea and vomiting associated with gastroparesis.

However, rare complications are possible during and after the surgery to implant the neurostimulator device, and there are some risk related to gastric electrical stimulation therapy. Complications related to implantation of the Enterra therapy system’s electrical stimulation device and gastric electrical stimulation can potentially include:

  • Adverse reactions to general anesthesia during the procedure
  • Pain at the site of the implant, including irritation and inflammation
  • Perforation of the stomach wall
  • Mechanical obstruction of the bowel by the implanted leads
  • Uncomfortable or unwanted stimulation of the abdominal muscles
  • Post-surgical infection
  • Function issues with the leads or implanted device

Is Enterra Therapy Covered by Insurance?

While you’ll need to make sure your doctor requests prior authorization for coverage before receiving the Enterra Therapy System’s implantable gastric electrical stimulator, many health insurance companies are willing to cover Enterra therapy.

To receive authorization for Enterra therapy, your doctor will likely need to explain your symptoms and why gastric electrical stimulation is likely to relieve those symptoms. You may also need to call or write to your insurance company personally in order to receive approval for Enterra therapy.

Which Patients are Not Good Candidates for the Enterra Therapy System?

Enterra therapy and gastric electrical stimulation are a safe and effective treatment for many people with gastroparesis. But Enterra therapy doesn’t work on every patient, and is not appropriate for all patients. Your Hoag physician will be able to guide you. Learn more about our Hoag Midgut Digestive Team. Generally speaking, those who might not be good candidates for Enterra therapy and gastric electrical stimulation (GES) include:

  • Those who plan to undergo future medical procedures involving diathermy, which is a medical procedure that utilizes high-frequency electrical currents to relieve pain, destroy unwanted tissue, cause blood vessels to clot, etc. Those with implanted Enterra therapy devices should never undergo diathermy for any reason
  • Those who may need to undergo future MRI scans, as implanted devices like the Enterra Therapy System’s neurostimulator shouldn’t be exposed to powerful magnetic fields
  • Patients younger than 18, or older than 70
  • Those who cannot tolerate surgery or general anesthesia due to age, health, physical or mental disorders or other issues
  • Pregnant women, as Enterra therapy hasn’t been evaluated for use in patients who are pregnant