Temporary Gastric Stimulation Research Articles

P149 MINIMAL INVASIVE TEMPORARY GASTRIC ELECTRO STIMULATION - 1 YEAR FOLLOW

Abstract Aim To predict the outcome of the implantation of an electronic gastric stimulation device (Enterra®, Medtronic) we established a minimal invasive procedure to perform a temporary gastric test stimulation prior to a definite implantation (1). We achieved promising short time results. This study will demonstrate the long-term results after more than 1 year. Background & Methods Gastroparesis (GP) is a complex disorder of gastric motility. It is defined as a delayed gastric emptying without pyloric obstruction. Due to its etiology GP is divided into three groups: diabetic (GP), postoperative (PG) and idiopathic (IP). Although electronic stimulation of the stomach is a well-established and approved procedure since over 18 years for the therapy of symptomatic GP, the response to gastric stimulation remains unpredictable. 13 patients (11 female, 2 male) with a history of symptomatic gastroparesis (4 idiopathic, 7 postoperative, 2 diabetic) were included. Patients underwent laparoscopy and received 2 temporary electrodes (Medtronic Streamline 6492®) 10 cm proximal to the pylorus into the gastric wall. Threads were passed through the abdominal wall and connected to an external gastric stimulator (Enterra, Fa. Medtronic). The device was taped to the abdominal wall by a dressing. Symptom intensity was measured by a standardized questionnaire, Gastoparesis Cardinal Symptom Index (GCSI)(2). Therapeutic response was defined as a GCSI reduction of at least 50% under the preoperative score. Half time gastric emptying was also measure pre and postoperatively using a half-solid test meal. Results 10 of 13 patients reported a response to temporary gastric stimulation with an increase of the pre-therapeutic GCSI over 50 %. 10 patients received a permanent stimulation device. 7 patients reached the 1-year follow up. They all remained responders with a reduction of GCSI over more than 50 %. In comparison to results after 6 months gastric half time emptying continued to decrease. Conclusion Temporary gastric electronic stimulation can predict the long-term outcome of patients receiving a definite implantation of an electronic gastric stimulation device.

The Effect of Gastric Electrical Stimulation on Small Bowel Motility in Patients With Gastroparesis and Concomitant Pancreatic and Small Bowel Dysfunction: From Animal Model to Human Application

Patients with gastroparesis often have biliary/pancreatic and small bowel symptoms but the effects of gastric electrical stimulation on small bowel electrical activity of the mid-gut have not been studied. Animal model aim: Establish gastric and upper small bowel/biliary slow wave activity relationships with electrical stimulation. Human study aim: Demonstrate improvement in symptoms associated with proximal small bowel dysmotility in gastric stimulated patients. Animal model: In vivo evoked responses of duodenal and Sphincter of Oddi measures recorded during gastric electrical stimulation in a nonsurvival swine model (N = 3). High-resolution electrical slow wave mapping of frequency, amplitude, and their ratio, for duodenal and Sphincter of Oddi electrical activity were recorded. Human study: Patients (N = 8) underwent temporary gastric stimulation with small bowel electrodes. Subjective and objective data was collected before and after temporary gastric stimulation. Symptom scores, gastric emptying times, and mucosal electrograms via low-resolution mapping were recorded. Animal gastric stimulation resulted in some changes in electrical activity parameters, especially with the highest energies delivered but the changes were not statistically significant. Human study revealed improvement in symptom and illness severity scores, and changes in small bowel mucosal slow wave activity. Gastric electrical stimulation in an animal model seems to show nonsignificant effects small bowel slow wave activity and myoelectric signaling, suggesting the existence of intrinsic neural connections. Human data shows more significance, with possible potential for therapeutic use of electrical stimulation in patients with gastroparesis and pancreato-biliary and small bowel symptoms of the mid-gut. This study was limited by the nonsurvival pig model, small sample size, and open label human study.

Temporary Gastric Stimulation in Patients With Gastroparesis Symptoms: Low-Resolution Mapping Multiple Versus Single Mucosal Lead Electrograms.

BackgroundCajal cells have a fundamental role in generating slow waves that regulate gastric motility. Gastric electrical stimulation (GES) is Food and Drug Administration (FDA)-approved for symptomatic treatment of drug refractory gastroparesis. We hypothesized that using two leads will vary from a single lead by providing greater insight of gastric electrical wave propagation, through differences in measured frequency, amplitude, and frequency over amplitude ratio. We also hypothesized that a significant reduction in symptomatic vomiting score is highly predictive in a single lead temporary gastric electrical stimulation.MethodsA total of 111 patients with drug-refractory gastroparesis were enrolled. Forty-two patients had single lead, while 69 patients had two leads. All recordings measured mean frequency and amplitude in each lead. Patients documented symptoms using standardized symptom scores at baseline and day 5 post-procedure.ResultsSingle lead patients with initial low mucosal frequency showed an increase from 3.10 to 4.93 (P = 0.0155), while the high frequency group decreased from 5.89 to 5.12 (P = 0.135). Vomiting score decreased significantly among both groups with GES (P = 0.0001). For two leads, the mucosal frequency decreased at the proximal electrode (P = 0.402), and increased at the distal electrode (P = 0.514), neither statistically significant (P = 0.143). Mucosal electrogram amplitude values changed for both proximal, mean decrease of 0.34 mV (P = 0.241), and distal, mean increase of 0.05 mV (P = 0.65) with a mean difference 0.34 mV (P = 0.238). However, mucosal electrogram frequency and amplitudes on day 5 were highly dependent on the baseline values (P < 0.001).ConclusionsCompared to the use of single point electrodes, the use of two low-resolution electrodes allows recording gastric electrical wave propagation with greater detail. Low resolution recording appears to be superior to single point recordings, while awaiting practical high-resolution recordings.

Minimally-invasive temporary gastric stimulation: A pilot study to predict the outcome of electronic gastric stimulation with the Enterra™ system

IntroductionGastroparesis (GP) is defined as delayed gastric emptying (GE) without any obstruction of the pylorus. It can be divided into idiopathic, diabetic, post surgical and rare causes. Electronic gastric stimulation (EGS) – Enterra Medtronic™ – is a part of GP therapy. Although its positive impact has been reported in open label trials, randomized controlled trials failed in demonstrating a positive outcome. The aim of this pilot study was to establish a reliable prediction for permanent gastric stimulation. Patients and procedure6 female patients underwent laparoscopic implantation of 2 temporary electrodes. The Enterra™ system was connected and taped to the skin. Baseline and postoperative gastroparesis cardinal symptom index (GCSI), a validated index for GP therapy, was assessed. Response to EGS was defined as a 50% decrease of baseline GCSI. Results4 of 6 patients responded to temporary EGS. 3 of 4 responders underwent permanent implantation. 1 non-responder received a permanent Enterra™ at another institution. After a median follow up time of 9months the responder group GCSI remained low, whereas the non-responder GCSI had increased. Moreover, the health care system was saved € 30,678.03 by this test stimulation concept. ConclusionLaparoscopic implantation of a temporary EGS system predicts the outcome of permanent gastric stimulation and is cost-saving.

Su1420 Evaluating Gastric Mucosal Nerve Density in Relation to Full Thickness Biopsy, Gastric Emptying, Symptoms and Response to Temporary Gastric Stimulation

Su1420 Evaluating Gastric Mucosal Nerve Density in Relation to Full Thickness Biopsy, Gastric Emptying, Symptoms and Response to Temporary Gastric Stimulation

Mucosal Temporary Gastric Stimulation for Patients With Symptoms of Gastroparesis: Proximal vs. Distal Leads Stimulation

Mucosal Temporary Gastric Stimulation for Patients With Symptoms of Gastroparesis: Proximal vs. Distal Leads Stimulation

Migraines and Gastroparesis: A Histologic, Physiologic, and Clinical Analysis with Temporary Gastric Stimulation

Purpose: A relationship between migraines and gastroparesis (GP) has been observed but the pathophysiology and mechanisms are unknown. We compared histologic, electrophysiologic, and clinical outcomes to define any differences between drug refractory GP patients with Migraines and those with No Migraines, undergoing temporary gastric electrical stimulation (GES). Methods: We reviewed data on 80 consecutive patients: 28 Migraine (35%) and 52 No Migraine (65%); 13 males, 67 female, mean age of 43 (26 diabetic, 53 idiopathic, 1 post surgical) undergoing temporary and latter permanent GES for drug refractory GP. Symptoms evaluated included vomiting, nausea, epigastric pain, bloating/distension, and anorexia/early satiety (scored from 0 to 4 for each) and total symptom score (TSS) with a max of 20. Vomiting score and TSS were measured before treatment and during treatment with temporary GES. Four hour Gastric Emptying Time (GET) % retention before and during treatment along with cutaneous, mucosal, and serosal EGG was also measured, reported as frequency and amplitude. Outcomes were reported as change in vomiting scores, change in TSS, and change in 4 hour GET. A full thickness gastric biopsy was performed at the time of subsequent permanent GES placement and was analyzed for S-100 (neuronal) and CD-117 (Cajal) cells. Two tailed unpaired t tests were performed for each category. Results: Vomiting and TSS scores at baseline were higher among patients with migraines. Also the migraine patients had more improvement in vomiting scores with temporary GES. Patients with migraines had more normal gastric emptying scores at baseline and a greater change after temporary GES. The amplitude of mucosal EGG in patients with Migraines was higher than in the No Migraine group. There was no statistical difference between the Migraine group and the No Migraine group in outer or inner S-100 cells (neuronal) outer or inner CD-117 (Cajal) cells, cutaneous EGG frequency and amplitude, or serosal EGG frequency and amplitude. (See Table).Table: Table. Comparison of Migraine vs. No MigraineConclusion: GP Patients with Migraines have different baseline physiology as well as better symptom improvement from temporary GES compared with No Migraine GP patients. Disclosure: Dr Thomas Abell-Licensor, Consultant, Investigator, Medtronic, Inc.

Visceral Sensitivity to Gastric Stimulation and its Correlation with Alterations in Gastric Emptying and Accommodation in Humans

The aim of this study was to investigate the visceral sensation to gastric stimulation and its correlation with the stimulation-induced alterations in gastric accommodation and gastric emptying. The study was performed in 12 healthy human controls. Gastric stimulation was performed using bipolar electrodes attached to the mucosa of the distal stomach under endoscopy. Experiments were conducted on 3 consecutive days to investigate the effects of gastric stimulation with various parameters on visceral sensation, maximum intake of water and gastric emptying of solids. 1) The stimulation energy was 265.6 +/- 134.9 smA 2 for the first sensation and 2,020.0 +/- 865.1 smA2 for the maximum tolerance, and there was a large variation among the subjects; 2) Gastric stimulation with stimulation energy less than 50% of that required to induce the first sensation significantly reduced the maximum intake of water and delayed gastric emptying of solids without inducing symptoms; 3) The stimulation energy of the first sensation was significantly correlated with the stimulation-induced reduction in water intake (r=-0.80, P=0.02) and the stimulation-induced prolongation of gastric emptying (r=-0.78, P=0.003). That is, the inhibitory effects of gastric stimulation were more obvious in those subjects who were viscerally more sensitive to gastric stimulation. Gastric stimulation via the distal stomach reduces gastric accommodation and delays gastric emptying. These inhibitory effects are correlated with the visceral sensitivity of the individual to gastric stimulation. It is worthy to further investigate whether the outcome of the implantable gastric stimulation (IGS) therapy for obesity may be predicted from the visceral sensitivity of the patient to temporary gastric stimulation using endoscopically placed mucosal electrodes.

Effects of Temporary Gastric Electrical Stimulation With Endoscopically Placed Electrodes: A Report Of 41 Consecutive Patients

Purpose: We have previously demonstrated that short term gastric electrical stimulation (GES) can be performed with electrodes placed through PEG tubes or via an upper endoscope (Neurogastroenterol Motility 14: 422, 2002). We now report on 41 consecutive patients receiving temporary endoscsopic GES electrode placement to deliniate their characteristics. Methods: 41 patients with the symptoms of gastroparesis and documented disordered gastric emptying (GET) underwent endoscopic placement of electrodes. Patients were 9 m, 32 f with a diagnosis of 27 Idiopathic, 5 Diabetes Mellitus, 9 Post Surgical, mean age 42 years. Endoscopic placement was performed as previously reported using an upper endoscope, a 7F gastric stimulation electrode, and several endoscopically placed clips, fixing the electrode at the antral-body junction. GES was preformed as previously reported (Digestion 66: 204-212, 2002) as were GET and EGG and reported as mean SE. Symptoms of nausea and vomiting (0-4) and GI total symptom score (TSS 0-20) were quantified. Results: Of the 41 patients, all 41 had successful placement of GES electrodes. 36 patients retained the electrodes for at least 3 days, allowing measurement of symptoms and a repeat GET. The symptoms and related characteristics are reported in the table. Of the 41 patients, 39 reported significant improvement in nausea, vomiting, the GI total symptom score (TSS). GET EGG changes were not significantly different although GET % retention did improve and approached significance at 4 Hr. There were no complications of the procedure, and stimulator electrodes were removed easily at the end of the temporary GES period. Conclusion: We conclude that temporary gastric stimulation electrodes are safely and reliably placed endoscopically and that clinically useful information is quickly obtained, without requiring a surgical procedure.