Clinical UM Guideline


Subject: Gastric Electrical Stimulation
Guideline #: CG-SURG-70 Publish Date:    05/01/2018
Status: New Last Review Date:    01/25/2018


This document addresses gastric electrical stimulation for gastroparesis and other indications.

Gastric electrical stimulation (GES) describes the use of an implantable device to treat gastroparesis, a chronic disorder in which there is delayed gastric emptying without evidence of obstruction.  Symptoms include abdominal distension, nausea, and vomiting.  GES has more recently been investigated as a technique to treat obesity.

Clinical Indications

Medically Necessary:

Gastric electrical stimulation is considered medically necessary in the treatment of chronic intractable nausea and vomiting secondary to severe gastroparesis of diabetic or idiopathic etiology when the following criteria are met:

Not Medically Necessary:

Gastric electrical stimulation is considered not medically necessary in all other indications including but not limited to the treatment of obesity.


The following codes for treatments and procedures applicable to this guideline are included below for informational purposes. Inclusion or exclusion of a procedure, diagnosis or device code(s) does not constitute or imply member coverage or provider reimbursement policy. Please refer to the member's contract benefits in effect at the time of service to determine coverage or non-coverage of these services as it applies to an individual member.




Laparoscopy, surgical; implantation or replacement of gastric neurostimulator electrodes, antrum


Laparoscopy, surgical; revision or removal of gastric neurostimulator electrodes, antrum


Implantation or replacement of gastric neurostimulator electrodes, antrum, open


Revision or removal of gastric neurostimulator electrodes, antrum, open


Insertion or replacement of peripheral or gastric neurostimulator pulse generator or receiver, direct or inductive coupling [when specified as gastric neurostimulator]


Revision or removal of peripheral or gastric neurostimulator pulse generator or receiver [when specified as gastric neurostimulator]


Electronic analysis of implanted neurostimulator pulse generator system (eg, rate, pulse amplitude and duration, configuration of wave form, battery status, electrode selectability, output modulation, cycling, impedance and patient measurements) gastric neurostimulator pulse generator/transmitter [includes codes 95980, 95981, 95982]






For the following codes when specified as gastric neurostimulator:


Generator, neurostimulator, implantable, non-rechargeable


Lead, neurostimulator, implantable


Implantable neurostimulator, pulse generator, any type


Implantable neurostimulator electrode, each


Implantable neurostimulator pulse generator, dual array, non-rechargeable, includes extension



ICD-10 Procedure



Insertion of stimulator lead into stomach, open approach


Insertion of stimulator lead into stomach, percutaneous approach


Insertion of stimulator lead into stomach, percutaneous endoscopic approach


And for the following codes when specified as gastric neurostimulator:


Insertion of multiple array stimulator generator into chest subcutaneous tissue and fascia [by approach; includes codes 0JH60DZ, 0JH63DZ]


Insertion of stimulator generator into chest subcutaneous tissue and fascia [by approach; includes codes 0JH60MZ, 0JH63MZ]


Insertion of multiple array stimulator generator into abdomen subcutaneous tissue and fascia [by approach; includes codes 0JH80DZ, 0JH83DZ]


Insertion of stimulator generator into abdomen subcutaneous tissue and fascia [by approach; includes codes 0JH80MZ, 0JH83MZ]



ICD-10 Diagnosis



Diabetes mellitus due to underlying conditions


Drug or chemical induced diabetes mellitus


Type 1 diabetes mellitus


Type 2 diabetes mellitus


Other specified diabetes mellitus




Nausea and vomiting


Encounter for adjustment and management of neuropacemaker (brain) (peripheral nerve) (spinal cord) [when specified as GES device for diabetic or idiopathic gastroparesis]

Gastric stimulators of lesser curvature




Unlisted laparoscopy procedure, stomach [when specified as laparoscopic implantation, replacement, revision or removal of gastric stimulation electrodes, lesser curvature]


Unlisted procedure, stomach [when specified as open implantation, replacement, revision or removal of gastric stimulation electrodes, lesser curvature]


Note: Implantation, replacement, revision or removal of gastric stimulator devices of lesser curvature are considered Not Medically Necessary for all indications



ICD-10 Diagnosis



All diagnoses

Discussion/General Information

GES involves the implantation of a neuroelectrical stimulation device into the abdomen connected to wires that are attached to the wall of lower stomach.  The device sends high frequency, low energy electrical impulses to the stomach with the intention of alleviating chronic nausea and vomiting caused by gastroparesis by stimulating the smooth muscles of the stomach.

GES for Gastroparesis
Gastroparesis is a long-lasting and recurrent disorder caused by stomach pump failure.  Gastroparesis is characterized by severe epigastric pain, nausea and vomiting in the absence of mechanical obstruction.  Although gastroparesis sometimes develops as a complication of diabetes, frequently the cause is unknown (idiopathic).  The definitive diagnosis of gastroparesis typically is made using an isotope-labeled test meal.  Treatment is addressed progressively and includes education, dietary support and pharmacologic therapy (prokinetic and antiemetic agents).  For relatively mild gastroparesis, dietary modifications and a low-dose antiemetic or prokinetic agent might provide satisfactory control of symptoms.  Individuals with more severe symptoms of gastroparesis (refractory vomiting, pronounced dehydration, or uncontrolled blood glucose levels), may require hospitalization, intravenous hydration, insulin for blood glucose control, nasogastric stomach decompression, and/or intravenous administration of antiemetic and prokinetic agents.  GES is reserved for individuals who are refractory to medical management.

The Medtronic Enterra™ Therapy System received U.S. Food and Drug Administration (FDA) approval through a humanitarian device exemption as a treatment for refractory diabetic and idiopathic gastroparesis (IG).  As part of the FDA approval process, data was presented regarding 33 individuals with gastroparesis, either idiopathic or related to diabetes, who were studied in a double-blind randomized trial of the stimulator blindly turned on and off during two 1-month periods.  This study has been published in the peer reviewed medical literature (Abell, 2003).  Vomiting frequency was the principal outcome studied and subjects recorded daily vomiting episodes in diaries before baseline and at follow-up visits.  The median overall frequency of vomiting was 17.3 episodes, which declined to 6.8 episodes during the on period, compared to 13.5 episodes when the device was turned off.  When looking individually at those with IG, there was a similar drop in vomiting frequency compared to baseline, regardless of whether the device was turned on or off suggesting a placebo effect.  In contrast, in those with gastroparesis related to diabetes, there was a small drop in vomiting frequency compared to baseline with the device turned off, compared to a larger drop in vomiting frequency with the device turned on, suggesting a lack of a placebo effect.  It is recognized that this trial recruited only very small numbers of individuals; specifically only 17 participants had diabetic gastroparesis (DG).  However, it is also recognized that DG is an unusual and severe disorder with few other treatment options if the individual is refractory to medical management. 

In 2015, Brody and colleagues analyzed the pre- and postoperative pain and function scores over time in subjects at a single institution who had undergone implantation with a GES device for refractory gastroparesis.  As a secondary goal, the researchers also assessed the reoperation rate and types of operations after GES.  Between 2003 and 2013, a total of 79 subjects (66 females and 13 males) underwent GES.  Symptom scores were available for 60 participants at baseline, 52 participants at 1 year, 14 participants during years 2 to 3, and 18 participants for 4 to 8 years.  Overall, symptom reductions were maintained for 8 years for both functional and pain symptoms.  At 1 year follow-up, 44% and 31% of the participants experienced at least a 25% reduction in symptom distress for functional and pain symptoms, respectively.  At 4-8 year follow-up, 67% and 33% of the participants experienced at least a 25% reduction in symptom distress for functional and pain symptoms, respectively.  Preoperatively, 9 individuals required nutrition supplementation compared to 4 participants postoperatively.  Post-implantation, 34 (43%) individuals underwent additional operations, with a mean of 2.15 operations per subject.  The most common indications for reoperation were generator-related causes, including battery exchanges and relocation.  Other operations included gastrectomies (n=8) and median arcuate ligament releases (n=7).  There were no mortalities during the initial 30-day postoperative period, however, a total of 11 participants (14%) died during the study period.  All deaths were unrelated to stimulator placement, with 8 deaths in the diabetic participants and 3 deaths among the idiopathic group.  The authors acknowledged that a limitation of the study is its non-randomized, uncontrolled design.  The authors also acknowledged that a placebo effect could be argued for the results after GES but thought it would be difficult to imagine a placebo effect that would last more than a few weeks after surgery.

Chu and colleagues (2012) reported the results of a meta-analysis to assess the effects of gastric electrical stimulation (GES) on symptoms and gastric emptying in subjects with gastroparesis and the effects of GES on individuals with DG, IG and postsurgical gastroparesis.  A literature search of clinical trials using high-frequency GES to treat subjects with gastroparesis from January 1995 to January 2011 was performed.  Data on the total symptom severity score (TSS), vomiting severity score, gastric emptying and nausea severity score, were extracted and analyzed.  The analysis included a total of 10 studies (n=601).  When compared to baseline, it was noted that GES significantly improved both TSS (p<0.00001) and gastric retention at 2 hours (h) (p=0.003) and 4 h (p<0.0001) in individuals with DG.  Gastric retention at 2 h (p=0.18) in individuals with IG, and gastric retention at 4 h (p=0.23) in individuals with postsurgical gastroparesis (PSG), did not reach significance.  Based on this meta-analysis, the authors concluded that GES is an effective and safe method for treating refractory gastroparesis.  Individuals with DG seem the most responsive to GES, both subjectively and objectively, while the IG and PSG subgroups are less responsive and need further research.

The long-term safety and efficacy of GES therapy was reported in a study by McCallum and colleagues (2011).  Their retrospective case series study enrolled 221 subjects with refractory gastroparesis (n=142 diabetic, n=48 idiopathic, and n=31 postsurgical) who were treated with the Enterra device and followed for up to 10 years (range 1-10 years).  At 1 year, 188 (85%) of the initial 221 subjects enrolled were available for follow-up.  Total symptom score (TSS) was reported to have decreased by 53% ± 32% (p<0.001).  Additionally, all 7 individual GP symptom measures on the TSS were significantly reduced for all subjects (p<0.0001).  Participants with DG had greater symptom reduction than those with PSG and IG (55% vs. 48% vs. 47%, respectively).  Of 119 subjects with gastric emptying data, 26% normalized their results after GES therapy (p<0.05).  Overall the weight for all subjects (n=124) increased significantly from 149 ± 41 lbs at baseline to 162 ± 43 lbs at last follow-up (p<0.05).  Importantly, for subjects with DG, hospitalization days decreased by 87% (p<0.001) in the last year of follow-up.  Overall, the use of GP medications in all subject groups was reduced after 1 year of GES (74% at baseline vs. 56% for prokinetics, p=0.05; and 65% at baseline vs. 58% for antiemetics, p=0.025).  With regard to adverse events, 24 subjects (11%) had their GES devices removed: 13 (7%) due to infection, 5 due to lead dislodgement, and 6 due to lack of improvement.  Ten subjects (7 DG and 3 PSG) required a total gastrectomy for failure to improve symptoms.  Ten subjects had their GES system repositioned or replaced: 4 were due to depleted battery; 4 were related to lead dislodgement secondary to trauma or twisted wires; and 2 were due to device migration.  The authors conclude that GES therapy significantly improved subjective and objective parameters in subjects with severe gastroparesis.  It must be noted that while the number of subjects completing follow-up to 1 year is provided, there is no data regarding how many subjects reached other time points, including the stated 10 year point. 

An earlier study by McCallum and colleagues (2010) was a randomized controlled trial evaluating Enterra therapy in individuals with chronic intractable nausea and vomiting from DG.  Fifty-five subjects with refractory DG were implanted with the Enterra system.  After surgery, all participants had the stimulator on for 6 weeks and then were randomly assigned to groups that had consecutive 3-month cross-over periods with the device either on or off.  After this period, the device was turned on in all participants and they were followed up unblinded for 4.5 months.  During the initial 6-week phase with the stimulator turned on, the median reduction in weekly vomiting frequency (WVF) compared with baseline was 57%.  There was no difference in WVF between the individuals who had the device turned on or off during the 3-month cross-over period.  At 1 year, the WVF of all participants was significantly lower than baseline values (median reduction, 68%; p<0.001).  The study participants also had improvements in total symptom score, gastric emptying, quality of life and median days in the hospital.  One participant had the device removed due to infection, while 2 of the study participants required surgical intervention due to lead-related problems.  The authors concluded that in individuals with intractable DG, GES for 6 weeks using the Enterra system resulted in a significant reduction in vomiting and gastroparetic symptoms.

One case series of 48 participants reported that GES was associated with improved symptoms, glucose control, nutritional status and hospitalizations (Lin, 2004).  Another case series of 17 individuals with DG reported improvements in symptoms and glucose control (van der Voort, 2005).  Other small case series have focused on a mixture of individuals with IG and DG, limiting interpretation regarding the subgroup of subjects with IG (Abell, 2003).

In 2013, the American College of Gastroenterology published a new clinical guideline addressing the treatment of gastroparesis (Camilleri, 2013).  Their recommendation regarding gastric electric stimulation states:

GES may be considered for compassionate treatment in subjects with refractory symptoms, particularly nausea and vomiting. Symptom severity and gastric emptying have been shown to improve in subjects with DG, but not in subjects with IG or PSG. (Conditional recommendation, moderate level of evidence).

They acknowledge that there is currently no consensus or societal guideline on the selection of subjects (for example, failed therapeutic trials, or level of nutritional compromise) for the use of GES as compassionate treatment.

The National Institute for Health Care and Excellence (NICE) published an interventional procedure guideline supporting the use of gastroelectrical stimulation as an option for treating chronic, intractable nausea and vomiting secondary to gastroparesis (NICE, 2014).

GES for Morbid Obesity
GES has also been investigated as a treatment of obesity as a technique to increase a feeling of satiety with subsequent reduced food intake and weight loss.  The exact mechanisms resulting in changes in eating behavior are uncertain but may be related to neuro-hormonal modulation and/or stomach muscle stimulation (Cigaina, 2003).  There are no GES devices approved by the FDA for the treatment of obesity.  However, the Transcend™ implantable gastric stimulation device, manufactured by Medtronic Transneuronix, (formerly manufactured by Transneuronix Corporation), is currently available in Europe for treatment of obesity.  An assessment of GES for obesity by the Swedish Council on Technology Assessment in Healthcare found that gastric pacing is still an experimental method and should be used only in scientific studies that have been approved by a research ethics committee (Swedish Council on Technology Assessment in Healthcare, 2004).


Antiemetic drug: A drug used to treat nausea and vomiting. The principal classes of antiemetic drugs are antidopaminergics, antihistamines, anticholinergics, phenothiazines and serotonin 5-HT3 receptor antagonists. Examples of such drugs include but are not limited to: prochlorperazine, trimethobenzamide, and promethazine.

Gastric: This term refers to the stomach.

Gastroparesis: A condition where there is delayed gastric emptying due to abnormal gastric motility in the absence of obstruction.

Motility: The power to move spontaneously.

Prokinetic drug: A drug used to speed up gastric emptying time. Examples of commonly used agents include, but are not limited to, erythromycin and metoclopramide (Reglan).

Scintigraphic imaging of gastric emptying: A technique which involves incorporating a radioisotope tracer into a standard meal and tracing its passage through the stomach using a gamma camera; considered the gold standard for diagnosing delayed gastric emptying because this test quantifies the emptying of a physiologic caloric meal.


Peer Reviewed Publications:

  1. Abell T, Lou J, Tabbaa M, et al. Gastric electrical stimulation for gastroparesis improves nutritional parameters at short, intermediate, and long-term follow-up. JPEN J Parenter Enterel Nutr. 2003a; 27(4):277-281.
  2. Abell T, McCallum R, Hocking M, et al. Gastric electrical stimulation for medically refractory gastroparesis. Gastroenterology. 2003; 125(2):421-428.
  3. Brody F, Zettervall SL, Richards NG, et al. Follow-up after gastric electrical stimulation for gastroparesis. J Am Coll Surg. 2015; 220(1):57-63.
  4. Chu H, Lin Z, Zhong L, et al. Treatment of high-frequency gastric electrical stimulation for gastroparesis. J Gastroenterol Hepatol. 2012; 27(6):1017-1026.
  5. Cigaina V, Hirschberg AL. Gastric pacing for morbid obesity: plasma levels of gastrointestinal peptides and leptin. Obesity Research. 2003; 11(12):1456-1462.
  6. Cutts TF, Luo J, Starkebaum W, et al. Is gastric electric stimulation superior to standard pharmacological therapy in improving GI symptoms, healthcare resources, and long-term health care benefits? Neurogastroenterol Motil. 2005; 17(1):35-43.
  7. Lin Z, Forster J, Sarosiek I, McCallum RW. Treatment of diabetic gastroparesis by high-frequency gastric electrical stimulation. Diabetes Care. 2004; 27(5):1071-1076.
  8. McCallum RW, Lin Z, Forster J, et al. Gastric electrical stimulation improves outcomes of patients with gastroparesis for up to 10 years. Clin Gastroenterol Hepatol. 2011; 9(4):314-319.
  9. McCallum RW, Snape W, Brody F, et al. Gastric electrical stimulation with Enterra therapy improves symptoms from diabetic gastroparesis in a prospective study. Clin Gastroenterol Hepatol. 2010; 8(11):947-954.
  10. van der Voort IR, Becker JC, Dietl KH, et al. Gastric electrical stimulation results in improved metabolic control in diabetic patients suffering from gastroparesis. Exp Clin Endocrinol Diabetes. 2005; 113(11):38-42.
  11. Yao S, Ke M, Wang Z, et al. Retrograde gastric pacing reduces food intake and delays gastric emptying in humans: a potential therapy for obesity? Dig Dis Sci. 2005; 50(9):1569-1575.

Government Agency, Medical Society, and Other Authoritative Publications:

  1. Camilleri M, Parkman HP, Shafi MA, et al. American College of Gastroenterology. Clinical guideline: management of gastroparesis. Am J Gastroenterol. 2013; 108(1):18-37.
  2. Food and Drug Administration. EnterraÔ Therapy System (formerly named Gastric Electrical Stimulation) – H990014. Issued March 31, 2000. Available at: Accessed on November 29, 2017.
  3. Food and Drug Administration. Humanitarian Device Exemption. Last updated 03/27/208. Available at:
    . Accessed on April 24, 2018.
  4. National Institute for Clinical Excellence (NICE). Gastroelectrical stimulation for gastroparesis. Interventional procedures guidance (IPG489). London, UK: NICE; May 2014. Available at: Accessed on November 29, 2017.
  5. Parkman HP, Hasler WL, Fisher RS. American Gastroenterological Association medical position statement: diagnosis and treatment of gastroparesis. Gastroenterology 2004; 127(5):1589-1591. Available at: Accessed on November 29, 2017.
  6. Parkman HP, Hasler WL, Fisher RS; American Gastroenterological Association. American Gastroenterological Association technical review on the diagnosis and treatment of gastroparesis. Gastroenterology. 2004; 127(5):1592-1622. Available at: Accessed on November 29, 2017.
  7. Swedish Council on Technology Assessment in Healthcare (SBU). Gastric pacing (gastric electrical stimulation) for the treatment of obesity. Alert. Stockholm, Sweden: SBU; 2004.
Websites for Additional Information
  1. National Digestive Diseases Information Clearinghouse (NDDIC). Gastroparesis. Updated June 2012. Available at: Accessed on November 29, 2017.

The use of specific product names is illustrative only. It is not intended to be a recommendation of one product over another, and is not intended to represent a complete listing of all products available.







Medical Policy & Technology Assessment Committee (MPTAC) review. Initial document development. Moved content of SURG.00046 to new clinical utilization management guideline document with the same title.