Gastric electrical stimulation with Enterra requires a small medical device, called a neurostimulator, to be implanted under the skin, usually in the lower abdominal region. Two insulated wires, called leads, are implanted in the stomach wall muscle and then connected to the neurostimulator. The procedure is performed under general anesthesia.
The Enterra neurostimulator sends mild electrical pulses through the leads to stimulate the smooth muscles of the lower stomach. This may help to control the chronic nausea and vomiting caused by gastroparesis.
After the Enterra device is implanted, the doctor uses a handheld, external programmer to adjust the neurostimulator and customize the stimulation. Stimulation can be adjusted without surgery, and can be turned off by the doctor at any time if the person experiences any intolerable side effects.
The Enterra Therapy system for gastric electrical stimulation is FDA approved as a humanitarian device and is authorized by Federal law for use in treatment of chronic intractable (drug refractory) nausea and vomiting secondary to gastroparesis of diabetic or idiopathic etiology. The effectiveness of this device for this use has not been demonstrated.
A humanitarian device is a medical device specially designated by the US Food and Drug Administration (FDA) for use in the treatment of a rare medical condition (fewer than 4,000 new cases per year in the United States). The FDA requires that any physician who wishes to use the device to treat a patient must first obtain approval from the hospital’s institutional review board. The Medtronic Enterra Therapy system was designated as a device for humanitarian use by the FDA in 1999.
After Enterra Therapy was designated for humanitarian use, Medtronic submitted a Humanitarian Device Exemption (HDE) application to the FDA. This type of application is not required to contain the results of scientifically valid clinical investigations demonstrating that the device is effective for its intended purpose. However, it must contain sufficient information for the FDA to determine that the device does not pose an unreasonable or significant risk of illness or injury. It must also determine that the probable benefit to health outweighs the risk of injury or illness from its use, taking into account the probable risks and benefits of currently available devices or alternative forms of treatment. The applicant must demonstrate that no comparable devices are available to treat or diagnose the disease or condition, and that the applicant could not otherwise bring the device to market.
After the FDA approved the Humanitarian Device Exemption in 2000, Medtronic was able to manufacture and distribute Enterra Therapy in the United States.
The Enterra device was FDA approved for compassionate use in 1999. It is a neurostimulator that is placed surgically. Although this does not make the stomach empty normally, it interferes with the message of nausea to the brain, which can help improve the overall quality of life.
A feeding tube is a surgically placed tube that is placed in the small intestine. This is done to maintain nutrition without relying on the stomach. This can be temporary or permanent, depending on the disease process.
Pyloroplasty is a laparoscopic surgery where the valve that empties the stomach is cut and then sewed together in a more open fashion. This can help the stomach empty better and improve symptoms. There are some risks to the surgery, and it isn’t a good choice for everyone. Potential problems include reflux (including bile reflux which is difficult to treat with medications), persistence of gastroparesis symptoms, leaking from the surgery site, and infection.
If other interventions are not successful in improving severe symptoms, Dr. Bell may discuss removing a large portion of the stomach. This is called a partial gastrectomy.