Enterra Therapy Gastric Stimulation System (Enterra)

Enterra Therapy Gastric Simulation System (Enterra Therapy) is indicated for the treatment of patients with long term, uncontrolled (not helped by medication) nausea and vomiting from gastroparesis of diabetic or idiopathic origin. In March 2000, the Food and Drug Administration (FDA) gave approval of a humanitarian Device Exemption (HDE) of a Humanitarian Use Device (HUD) for Enterra Therapy Gastric electrical (GES) Simulation System. Although, there is evidence that suggests the use of Enterra Therapy System probably helps patients, symptoms, the FDA's HDE approval indicates that the helpfulness of this therapy has not been proven. Physicians at Columbia University Medical Center hope to prove the helpfulness of this device.

Gastroparesis is a debilitating disease in which patients suffer from a number of upper gastrointestinal (GI) symptoms including nausea, vomiting, early satiety, bloating, postprandial fullness, epigastric pain and burning, and cardiac pain and burning. Severe symptoms, particularly vomiting and nausea, can significantly impair a patients daily activities and quality of life. Current medical practice for the treatment and/or management of gastroparesis consists of dietary modifications, drug therapies, enteral feeding, parenteral feeding and surgery. These treatments are successful for some patients, but have significant drawbacks. Patients may initially be treated with various dietary modifications including frequent low fat meals. However, if dietary modifications alone are unsuccessful, antiemetic and prokinetic drugs, or combinations thereof, are generally tried. If symptoms cannot be controlled with medication, supplemental nutrition via enteral or parenteral feeding may be required to maintain hydration and nutritional status. Prokinetic drugs are intended to promote gastric motility, i.e., to return abnormally slow gastric emptying states to normal. Antiemetic drugs are intended to alleviate symptoms of nausea and vomiting, but have no effect on motility. None of the prokinetic drugs are labeled for improved gastric emptying in gastroparesis. Metoclopramide is the only antiemetic or prokinetic drug indicated for use in the treatment of symptoms of diabetic gastroparesis. Surgical procedures are occasionally employed to manage symptoms of gastroparesis while maintaining the ability for enteral feeding. Surgical procedures, including gastrectomy, pyloroplasty, and gastrojejunostomy, have had limited success in managing symptoms of gastroparesis. When drug therapies or surgery are ineffective, supplemental enteral feeding via gastric or jejunal feeding tubes or total parenteral nutrition (TPN) may be required to meet the patient's nutritional needs. For those patients who cannot be adequately treated or managed by current medical practice, the GES has no satisfactory alternative. It is this group of patients for which the GES System is indicated.

The Enterra Therapy Gastric Stimulator will be used on subjects who have failed all other medical options to treat gastroparesis and all have a gastric stimulator implanted.

The intramuscular stomach leads, implanted in a minimally invasive surgical procedure lasting 1-3 hours, are placed on the greater curvature of the stomach. The implanted pulse generator (IPG) is about 2 1/2" x 2" x 1/2" and is implanted in a subcutaneous pocket, generally created in the abdominal area, and is then connected to the leads. The IPG provides the energy source that delivers the electrical pulse to the stomach muscle through the stomach leads to improve the symptoms of gastroparesis. The doctor will use an external programmer to change the settings of the neurostimulator and control the neurostimulator after implantation. Part of the programmer is held outside the body over the implant site and can adjust or change the settings of the neurostimulator using radio remote control.

Inclusion Criteria: Chronic(long term, lasting greater than 3 months) Intractable (drug refractory, failed medical management with prokinetic and antiemetic drugs Failed dietary modifications, and/or requiring enteral feeding) nausea and vomiting secondary to gastroparesis of diabetic or idiopathic etiology Exclusion Criteria: Only patients whom the physician determines are not a candidate for surgical procedures and/or anesthesia due to physical or mental conditions will be excluded. This includes pregnant women, anyone unable to tolerate general anesthesia, and uncorrectable coagulopathy.