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Xu X, Lei Y, Liu S, Chen JDZ. Inhibitory effects of gastrointestinal electrical stimulation on rectal tone are both organ-specific and distance-related in dogs. Dis Colon Rectum 2008; 51:467-73. [PMID: 18175187 DOI: 10.1007/s10350-007-9129-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/27/2007] [Revised: 07/22/2007] [Accepted: 08/11/2007] [Indexed: 02/08/2023]
Abstract
PURPOSE A phenomenon of cross-talk has been noted that electrical stimulation of one part of the gut affects another part of the gut. This study was designed to investigate whether the effect of electrical stimulation of one part of the gut on another part of the gut was related to the organ or the distance between the stimulation site and the affected organ, and the mechanism of ileum electrical stimulation on rectal tone. METHODS This study was performed in 13 healthy dogs (16-28 kg) in the fasting state. Experiments were performed to study 1) effects of gastric electrical stimulation, duodenal electrical stimulation, ileum electrical stimulation, and colonic electrical stimulation on rectal tone, and 2) the sympathetic and nitrergic pathways involved in the effects of ileum electrical stimulation on rectal tone. A computerized barostat was used to assess rectal tone. RESULTS All methods of stimulations significantly inhibited rectal tone. Duodenal electrical stimulation was least effective in reducing rectal tone. The percentage of increase in rectal volume was distance-related with duodenal electrical stimulation, ileum electrical stimulation, and colonic electrical stimulation but organ-specific with gastric electrical stimulation. The inhibitory effect of ileum electrical stimulation on rectal tone was abolished by N omega-nitro-L-arginine but not guanethidine. CONCLUSIONS Electrical stimulation of the stomach, intestine, or colon with long pulses has an inhibitory effect on rectal tone. This inhibitory effect is organ-specific as well as associated with the distance between stimulation site and affected organs. The inhibitory effect of ileum electrical stimulation on rectal tone is mediated by the nitrergic but not sympathetic pathway.
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Affiliation(s)
- Xiaohong Xu
- Veterans Research and Education Foundation, VA Medical Center, Oklahoma City, OK, USA
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152
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Abstract
Gastroparesis is a disorder of gastric emptying that occurs in the absence of mechanical obstruction. Its cardinal features include nausea, vomiting, bloating, early satiety and discomfort. Weight loss, dehydration, electrolyte disturbances and malnutrition may develop in severe cases. The majority of cases is idiopathic, long standing diabetes mellitus is responsible for about 25-30% of cases. Diabetic gastroparesis may render glucose control extremely difficult, its treatment represents a major challenge. Besides frequent, small meals and psychological support, several drug options are available, however, their efficacy is limited and only a few randomized studies have been performed to date. Prokinetic agents (erythromycin, domperidone, metoclopramide) and antiemetics (phenothiazines, serotonin antagonists, butyrophenones) are the most wide-spread medicaments. Among the novel, recently developed agents, 5-HT4 serotonin receptor agonists and dopamine D2 receptor antagonists are the most promising. Injection of botulinum toxin into the pyloric sphincter resulted in faster gastric emptying and symptom alleviation in some studies. Gastric electric stimulation appears to be one of the most effective options, both low and high-frequency stimulation may alleviate symptoms. Gastrostomy/jejunostomy and other surgical interventions are considered as "last resort".
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Affiliation(s)
- Péter Igaz
- Semmelweis Egyetem, Altalános Orvostudományi Kar II Belgyógyászati Klinika, Budapest, Hungary.
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153
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Xu J, Chen JDZ. Intestinal electrical stimulation improves delayed gastric emptying and vomiting induced by duodenal distension in dogs. Neurogastroenterol Motil 2008; 20:236-42. [PMID: 17931341 DOI: 10.1111/j.1365-2982.2007.00995.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The aim of this study was to investigate the effects of short-pulse intestinal electrical stimulation (IES) on duodenal distention-induced delayed gastric emptying and vomiting in dogs and its possible mechanisms. The study was performed in 12 dogs with jejunal electrodes and a duodenal cannula in three separate experiments to investigate the effects of IES on duodenal distension (DD)-induced delayed gastric emptying and discomfort signs, vagal efferent activity, and jejunal tone. We found that: (i) IES significantly accelerated gastric emptying of liquid delayed by distension (18.05 +/- 4.06%vs. 7.18 +/- 1.99%, P = 0.036 at 60 min). (ii) IES significantly reduced vomiting and discomfort/pain induced by distension. The average signs score was 15.33 +/- 1.37 during distension which decreased to 6.50 +/- 0.91 (P = 0.0002) with IES. (iii) IES did not change vagal afferent activity, which was assessed by the spectral analysis of the heart rate variability. (iv) IES decreased jejunal tone. In conclusion, IES with parameters commonly used in gastric electrical stimulation for nausea and vomiting associated with gastroparesis improves DD-induced delayed gastric emptying and prevents DD-induced vomiting and discomfort signs. Further studies are warranted to investigate the therapeutic potential of IES for gastrointestinal symptoms associated with disturbances in motility and sensory function in small intestine.
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Affiliation(s)
- J Xu
- Division of Gastroenterology, University of Texas Medical Branch, Galveston, TX 77555-0632, USA
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154
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Affiliation(s)
- Jieyun Yin
- Division of Gastroenterology, University of Texas Medical Branch, Galveston, Texas
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155
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Hou X, Song GQ, Yang B, Sun Y, Qian W, Chen JDZ. Effects of gastric electrical stimulation with short pulses and long pulses on gastric dysrhythmia and signs induced by vasopressin in dogs. Dig Dis Sci 2008; 53:630-5. [PMID: 17721728 DOI: 10.1007/s10620-007-9918-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/27/2006] [Accepted: 07/04/2007] [Indexed: 01/17/2023]
Abstract
AIMS This study was to investigate the effect of gastric electrical stimulation (GES) with short pulses, long pulses, short-pulse trains or long-pulse trains on gastric dysrhythmia and motion-sickness signs induced by vasopressin. METHODS Seven male beagle dogs implanted with four pairs of electrodes on gastric serosa were studied. The study was performed in six sessions in a randomized order. In session 1 or 2, either saline or vasopressin was infused without GES. In session 3, 4, 5 and 6, GES with short pulses, long pulses, trains of short pulses or trains of long pulses was performed before and during vasopressin infusion. Gastric slow waves and motion-sickness signs were recorded in each session. RESULTS (1) Vasopressin induced gastric dysrhythmia and motion sickness-like signs (ANOVA, P < 0.001). (2) GES with short pulses or trains of short pulses was capable of preventing vasopressin-induced emetic response (P < 0.001), but did not normalize gastric dysrhythmia. (3) GES with long pulses or trains of long pulses was able to normalize gastric dysrhythmia induced by vasopressin (P < 0.001), but showed no effects on vasopressin-induced motion-sickness signs. CONCLUSION GES with short pulses or trains of short pulses prevents vasopressin-induced emetic response with no improvement in gastric dysrhythmia. GES with long pulses or trains of long pulses normalizes gastric dysrhythmia induced by vasopressin with no effects on signs.
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Affiliation(s)
- Xiaohua Hou
- Division of Gastroenterology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, PR China.
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156
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Abstract
The onset of obesity occurs as a result of an imbalance between nutrient consumption/absorption and energy expenditure. Gastrointestinal (GI) motility plays a critical role in the rate of consumption of foods, digestion, and absorption of nutrients. Various segments of the GI tract coordinate in a complex yet precise way, to control the process of food consumption, digestion, and absorption of nutrients. GI motility not only regulates the rates at which nutrients are processed and absorbed in the gut, but also, via mechanical and neurohormonal methods, participates in the control of appetite and satiety. Altered GI motility has frequently been observed in obese patients, the significance of which is incompletely understood. However, these alterations can be considered as potential contributing factors in the development and maintenance of obesity and changed eating behavior. Therapies aimed at regulating or counteracting the observed changes in GI motility are being actively explored and applied clinically in the management of obese patients.
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Two-channel gastric pacing with a novel implantable gastric pacemaker accelerates glucagon-induced delayed gastric emptying in dogs. Am J Surg 2008; 195:122-9. [PMID: 18082553 DOI: 10.1016/j.amjsurg.2007.04.007] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2006] [Revised: 04/09/2007] [Accepted: 04/09/2007] [Indexed: 01/15/2023]
Abstract
BACKGROUND The aim of the current study was to investigate the efficacy of 2-channel gastric electrical stimulation (GES) with a custom-made implantable pacemaker on delayed gastric emptying and gastric dysrhythmia induced by glucagon in dogs. METHODS Six dogs were studied in 4 randomized session (saline, glucagon, glucagon with single-channel or 2-channel GES). GES was applied via the first pair of electrodes for single-channel GES or the first and third pairs of electrodes for 2-channel GES. Gastric emptying was assessed for 90 minutes and gastric slow waves were recorded at the same time. RESULTS Both single-channel and 2-channel GES improved gastric dysrhythmia (P < .05 vs glucagon session). Two-channel GES but not single-channel GES improved glucagon-induced delayed gastric emptying at 30 minutes, 45 minutes, 60 minutes, 75 minutes, and 90 minutes. CONCLUSION Two-channel GES with a novel implantable pacemaker is more efficient and effective than single-channel GES in improving delayed gastric emptying induced by glucagon. This implantable multipoint pacemaker may provide a new option for treatment of gastric motility disorders.
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Maranki J, Parkman HP. Gastric electric stimulation for the treatment of gastroparesis. Curr Gastroenterol Rep 2007; 9:286-94. [PMID: 17883975 DOI: 10.1007/s11894-007-0032-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Gastric electric stimulation is an emerging therapy for refractory gastroparesis. Several methods have been used to electrically stimulate the stomach. Initial studies used gastric electrical pacing, which entrains and paces the gastric slow waves at a slightly higher rate than the patient's normal myoelectric frequency of 3 cycles per minute (cpm). The technique currently practiced uses high-frequency, low-energy stimulation at four times the basal rate (12 cpm). Results from published studies with high-frequency stimulation reveal an improvement in symptoms, primarily of nausea and vomiting, and primarily in patients with diabetic gastroparesis, with only a modest change in gastric emptying. As treatment with gastric electric stimulation evolves, further delineation of its overall effectiveness, the type of patient that will likely respond, optimal electrode placement(s), and stimulus parameters should be explored.
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Affiliation(s)
- Jennifer Maranki
- Gastroenterology Section, Temple University School of Medicine, Gastroenterology Section, Parkinson Pavilion, 8th Floor, 3401 North Broad Street, Philadelphia, PA 19140, USA
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Abstract
Patients with gastroparesis present with gastrointestinal symptoms and non-gastrointestinal manifestations in association with objective delays in gastric emptying. The condition complicates the course of many patients with type 1 diabetes mellitus, usually in those with longstanding poor glycemic control with other associated diabetic complications. The diagnosis is made by directed evaluation to exclude organic diseases that can mimic the clinical presentation of gastroparesis, coupled with verification of gastric retention. Current therapy relies on dietary modifications, medications to stimulate gastric evacuation, and agents to reduce vomiting. Endoscopic and surgical options are increasingly used in patients who are refractory to drug treatment.
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Affiliation(s)
- William L Hasler
- Division of Gastroenterology, University of Michigan Health System, 3912 Taubman Center, Box 0362, Ann Arbor, MI 48109, USA.
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Song GQ, Hou X, Yang B, Sun Y, Qian W, Chen JDZ. A novel method of 2-channel dual-pulse gastric electrical stimulation improves solid gastric emptying in dogs. Surgery 2007; 143:72-8. [PMID: 18154935 DOI: 10.1016/j.surg.2007.07.001] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2006] [Revised: 06/21/2007] [Accepted: 07/01/2007] [Indexed: 12/27/2022]
Abstract
BACKGROUND Gastric electrical stimulation (GES) is known to improve vomiting with short pulses, normalize dysrhythmia with long pulses, and accelerate gastric emptying with 2 channels. The aim of this study was to assess the effects of a new method GES, namely, 2-channel GES with dual pulses on gastric emptying of solids as well as gastric dysrhythmia and emetic responses. METHODS Seven beagle dogs implanted with 4 pairs of electrodes were studied. A novel method of GES was proposed: 2-channel dual-pulse GES in which each stimulus was composed of a short pulse followed with a long pulse, and stimulation was delivered at 2 different locations. The study was performed to test the effects of this new method of GES on vasopressin-induced delayed gastric emptying of solids, gastric dysrhythmia, and emetic responses. RESULTS (1) Vasopressin-induced gastric dysrhythmia and emetic responses, as well as delayed gastric emptying of solids (P < .01). (2) Two-channel, but not 1-channel, dual-pulse GES was able to accelerate vasopressin-induced delayed gastric emptying of solids. (3) Both 1- and 2-channel dual-pulse GES was capable of improving dysrhythmia and emetic responses (P < .01). CONCLUSIONS The novel method of 2-channel dual-pulse GES is capable of accelerating gastric emptying of solids and improving dysrhythmia and emetic responses induced by vasopressin. This new method of GES may have a potential for gastroparesis.
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Affiliation(s)
- Geng-Qing Song
- Division of Gastroenterology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, PR China
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Yin J, Chen JD. Excitatory effects of synchronized intestinal electrical stimulation on small intestinal motility in dogs. Am J Physiol Gastrointest Liver Physiol 2007; 293:G1190-5. [PMID: 17916650 DOI: 10.1152/ajpgi.00092.2007] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The aim of this study was to investigate effects of synchronized intestinal electrical stimulation (SIES) on small intestinal motility in dogs. Seventeen dogs were equipped with a duodenal cannula for the measurement of small bowel motility using manometry; an additional cannula was equipped in six of the dogs with 1.5 m distal to the first one for the measurement of small intestinal transit. Two pairs of bipolar electrodes were implanted on the small intestinal serosa with an interval of 5 cm; glucagon was used to induce postprandial intestinal hypomotility. Eleven dogs were used for the assessment of the small intestinal contractions in both fasting and fed states. The other six dogs were used for the measurement of small intestinal transit. We found that 1) SIES induced small intestinal contractions during phase I of the migrating motor complex (MMC) (contractile index or CI: 5.2 +/- 0.6 vs. 10.3 +/- 0.7, P = 0.003); 2) in the fed state, SIES significantly improved glucagon-induced small intestinal postprandial hypomotility (CI: 3.4 +/- 0.5 vs. 6.0 +/- 0.3, P = 0.03); 3) SIES significantly accelerated small intestinal transit delayed by glucagon (70.4 +/- 3.1 vs. 44.5 +/- 3.1 min, P < 0.01); 4) there was a negative correlation between the CI and transit time (r = -0.427, P = 0.048); and 5) the excitatory effect of SIES was blocked by atropine. SIES may have a therapeutic potential for treating patients with small intestinal disorders.
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Affiliation(s)
- Jieyun Yin
- Div. of Gastroenterology, Univ. of Texas Medical Branch, , Rte. 0632, 1108 The Strand, Rm. 221, Galveston, TX 77555, USA
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162
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Abstract
BACKGROUND Gastroparesis is a disorder characterized by a delay in gastric emptying of a meal in the absence of a mechanical gastric outlet obstruction. AIM To provide an evidence based overview on diagnosis and management of gastroparesis. METHODS A PubMed search was performed using search terms including gastroparesis, gastric retention, gastric emptying, accommodation, manometry, prokinetics, antiemetics, metoclopramide, domperidone, erythromycin, botulinum toxin, gastric pacing. Relevant studies were identified and original articles and reviews were collected. References in these articles were examined for relevance and included where appropriate. RESULTS Diagnosis of gastroparesis is based on the presence of symptoms such as nausea, vomiting and postprandial abdominal fullness and on an objectively determined delay in gastric emptying. The true prevalence of gastroparesis is unknown. Gastric emptying can be assessed by scintigraphy and stable isotope breath tests. Management of gastroparesis consists of dietary and lifestyle measures and/or pharmacological interventions (prokinetics, antiemetics, intrapyloric botulinum toxin injection) or other interventions that focus on adequate nutrient intake either through a nasoduodenal tube, percutaneous gastrostomy or jejunostomy. CONCLUSIONS Accurate diagnosis of gastroparesis requires an adequate protocol to measure gastric emptying. Treatment options in gastroparesis remain limited despite the disabling nature of the disorder.
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Affiliation(s)
- J J L Haans
- Department of Internal Medicine, Division of Gastroenterology and Hepatology, University Hospital Maastricht, Maastricht, The Netherlands.
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163
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Li FY, Jiang LS, Cheng JQ, Mao H, Li N, Cheng NS. Clinical application prospects of gastric pacing for treating postoperative gastric motility disorders. J Gastroenterol Hepatol 2007; 22:2055-9. [PMID: 17593227 DOI: 10.1111/j.1440-1746.2007.05018.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Similar to the heartbeat, gastric peristalsis is regulated by an electrical rhythm generated by a pacemaker. Thus, electrical dysrhythmia of gastric slow waves will inevitably affect gastric peristalsis and emptying. The recurrence of postoperative gastroparesis is thereby closely related to the abnormalities of electrical dysrhythmia and ectopic pacemakers, resulting in postoperatively persistent gastric motility disorders in some severe cases, despite the use of prokinetic and antiemetic drugs. Recent studies have demonstrated that gastric pacing, analogous to pacing the human heart, is an attractive and promising therapy that is both feasible and safe. Gastric pacing has been shown to be strikingly effective in normalizing gastric dysrhythmia, increasing the activity of the gastric slow wave and thereby prompting gastric dynamia and emptying. Furthermore, the long-term utilization of gastric pacing can (i) relieve patients from clinical symptoms, such as nausea and vomiting; (ii) release patients with severe postoperative gastroparesis from relying on prokinetic drugs and the jejunal feeding tube; (iii) return patients to normal oral nutritional intake and provide a more satisfactory nutritional status and most importantly; and (iv) give patients a better quality of life. Overall, research focused on gastric pacing has demonstrated excellent prospects for clinical application in the treatment of postoperative gastroparesis disorders, especially for those unresponsive to prokinetic drugs.
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Affiliation(s)
- Fu-Yu Li
- Department of Hepatobiliary Surgery, West China Hospital of Sichuan University, Chengdu, China.
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164
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Gastric electrical stimulation: "scoping" out new directions. Gastrointest Endosc 2007; 66:987-9. [PMID: 17963886 DOI: 10.1016/j.gie.2007.07.034] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/16/2007] [Accepted: 07/23/2007] [Indexed: 01/05/2023]
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Abstract
PURPOSE OF REVIEW This review focuses on progress made in the field of gastric motility in the past year, emphasizing advances in understanding the motor physiology of the stomach in health and disease; noninvasive imaging technology and data on novel pharmacotherapeutics and other therapeutic interventions for gastroparesis. RECENT FINDINGS The differential conduction pattern in the interstitial cell of Cajal is responsible for the generation of the full spatio-temporal pattern of gastric peristalsis. The mitochondrial powerhouse provides the driving potential for the gastric slow waves. Females are more dependent on the nitrenergic system for gastric relaxation, which is predominantly affected in diabetes. The noninvasive modalities to evaluate gastric function have undergone substantial evolution in the past year. On the therapeutic front, a new generation of medications has been tested and holds promise for the near future. Gastric electrical stimulation is a viable option for medically refractory gastroparesis. SUMMARY Using dynamic imaging modalities, the pathophysiology of dyspepsia is becoming better understood and recognized as an end point of multifactorial dysfunction of the enteric neural circuitry. Mechanism-targeted drugs, stem cell transplantation and electrical stimulation options are becoming available.
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Affiliation(s)
- Arthi Sanjeevi
- Medical College of Virginia, Virginia Commonwealth University Medical Center, Richmond, Virginia 23298, USA.
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166
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Xu X, Pasricha PJ, Chen JDZ. Feasibility of gastric electrical stimulation by use of endoscopically placed electrodes. Gastrointest Endosc 2007; 66:981-6. [PMID: 17963885 DOI: 10.1016/j.gie.2007.05.020] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2006] [Accepted: 05/04/2007] [Indexed: 12/14/2022]
Abstract
BACKGROUND Gastric electrical stimulation (GES), which has been reported to have therapeutic potentials for gastroparesis and obesity, involves the surgical placement of electrodes with the patient under general anesthesia. New methods are needed for implanting GES electrodes in a safer and more feasible way. OBJECTIVE Our purpose was to investigate the safety and feasibility of placing electrodes endoscopically for GES. DESIGN AND SETTING A pilot study. SUBJECTS Six female hound dogs that weighed 13 to 22 kg. INTERVENTIONS Endoscopically placed electrodes passed through the abdomen and the stomach wall. MAIN OUTCOME MEASUREMENTS The study was performed in dogs surgically implanted with gastric serosal electrodes and endoscopically implanted electrodes. The experiment consisted of a 30-minute baseline, a 30-minute GES, and a 30-minute recovery. GES was performed through endoscopically placed electrodes. Gastric slow waves were simultaneously recorded with the serosal electrodes and the endoscopically placed electrodes. RESULTS (1) The slow wave frequency recorded from the endoscopically placed electrodes was significantly correlated with that from the serosal electrodes (r = 0.97, P < .002). (2) GES through the endoscopically placed electrodes was able to entrain gastric slow waves. (3) No gastric leakage into the abdominal cavity was noted and the dogs were healthy and comfortable. (4) The endoscopically placed electrodes remained for 2 to 3 weeks. LIMITATIONS The fixation of the electrodes needs to be improved for longer-term uses. CONCLUSIONS GES may be accomplished without surgery by inserting the electrode wire through the abdomen under endoscopy. The study results indicate that the endoscopically placed electrodes are effective for GES and do not result in any adverse events.
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Affiliation(s)
- Xiaohong Xu
- Division of Gastroenterology, University of Texas Medical Branch, Galveston, Texas, USA
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167
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Zhu H, Sallam H, Chen DD, Chen JDZ. Therapeutic potential of synchronized gastric electrical stimulation for gastroparesis: enhanced gastric motility in dogs. Am J Physiol Regul Integr Comp Physiol 2007; 293:R1875-81. [PMID: 17881615 DOI: 10.1152/ajpregu.00821.2006] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The aim of this study was to determine the effects and mechanism of synchronized gastric electrical stimulation (SGES) on gastric contractions and gastric emptying. The first experiment was designed to study the effects of SGES on antral contractions in four randomized sessions. Sessions 1 (control) and 2 (atropine) were performed in the fasting state, composed of three 30-min periods (baseline, stimulation, and recovery). Sessions 3 (control) and 4 (SGES performed during 2nd 20-min period) were performed in the fed state, consisting of two 20-min periods; glucagon was injected after the first 20-min recording. The second experiment was designed to study the effect of SGES on gastric emptying and consisted of two sessions (control and SGES). SGES was delivered with train duration of 0.5-0.8s, pulse frequency of 40 Hz, width of 2 ms, and amplitude of 4 mA. We found that 1) SGES induced gastric antral contractions in the fasting state. The motility index was 1.3 +/- 0.5 at baseline and 6.1 +/- 0.7 (P = 0.001) during SGES. This excitatory effect was completely blocked by atropine. 2) SGES enhanced postprandial antral contractions impaired by glucagon. 3) SGES significantly accelerated glucagon-induced delayed gastric emptying. Gastric emptying was 25.5 +/- 11.3% without SGES and 38.3 +/- 10.7% with SGES (P = 0.006 vs. control). This novel method of SGES induces gastric antral contractions in the fasting state, enhances glucagon-induced antral hypomotility in the fed state, and accelerates glucagon-induced delayed gastric emptying. The effect of SGES on antral contractions is mediated via the cholinergic pathway.
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Affiliation(s)
- Hongbing Zhu
- Veterans Research Foundation, Oklahoma City, Oklahoma, USA
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168
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Lin Z, Sarosiek I, McCallum RW. Gastrointestinal electrical stimulation for treatment of gastrointestinal disorders: gastroparesis, obesity, fecal incontinence, and constipation. Gastroenterol Clin North Am 2007; 36:713-34, x-xi. [PMID: 17950445 DOI: 10.1016/j.gtc.2007.07.007] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Electrical stimulation of the gastrointestinal (GI) tract is an attractive concept. Since these organs have their own natural pacemakers, the electrical signals they generate can be altered by externally delivering electric currents by intramuscular, serosal, or intraluminal electrodes to specific sites in the GI tract. This article reviews the advances in electrical stimulation of the GI tract by describing various methods of GI electrical stimulation and their peripheral and central effects and mechanisms; updating the status of GI electrical stimulation in the clinical settings of gastroparesis, obesity, fecal incontinence, and constipation; and predicting future directions and developments of GI electrical stimulation technology and their areas of possible clinical applications.
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Affiliation(s)
- Zhiyue Lin
- Center for GI Nerve and Muscle Function, Department of Internal Medicine, University of Kansas Medical Center, Mail Stop 1058, 3910 Rainbow Boulevard, Kansas City, KS 66160, USA
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169
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Abstract
Gastroparesis presents with gastrointestinal symptoms and nongastrointestinal manifestations in association with objective delays in gastric emptying. The condition may complicate several systemic disorders or may be idiopathic in nature. The diagnosis is made by directed evaluation to exclude organic diseases, which can mimic the clinical presentation of gastroparesis coupled with quantification of gastric emptying. Current therapies rely on dietary modifications, medications to stimulate gastric evacuation, and agents to reduce vomiting. Endoscopic and surgical options are increasingly used for cases refractory to medication treatment.
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Affiliation(s)
- William L Hasler
- Division of Gastroenterology, University of Michigan Health System, University of Michigan Hospital, 3912 Taubman Center, Box 0362, Ann Arbor, MI 48109, USA.
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170
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Song GQ, Chen JDZ. Synchronized gastric electrical stimulation improves delayed gastric emptying in nonobese mice with diabetic gastroparesis. J Appl Physiol (1985) 2007; 103:1560-4. [PMID: 17717123 DOI: 10.1152/japplphysiol.00319.2007] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The aim of this study was to investigate the effect and mechanism of synchronized gastric electrical stimulation (SGES) on gastric emptying in nonobese mice with diabetic gastroparesis (DB-GP). Eight control mice and 48 nonobese diabetic (NOD) mice with two pairs of gastric electrodes were used in this study. The study included seven groups in a randomized order [control, diabetes (DB), DB-GP, DB + SGES, DB-GP + SGES, DB-GP + Atropine, and DB-GP + SGES + Atropine groups]. In the control, DB, DB-GP, and DB-GP + Atropine groups, gastric emptying was measured in BLAB/cJ mice (control group) or NOD mice with a duration of diabetes of 0-7 days (DB group) or 28-35 days (DB-GP or DB-GP + Atropine group). In the DB + SGES, DB-GP + SGES, and DB-GP + SGES + Atropine groups, the experiment was the same as the corresponding DB, DB-GP, and DB-GP + Atropine groups except that SGES was applied during the experiment. SGES was applied via the proximal pair of electrodes and synchronized with the intrinsic gastric slow waves. The following results were obtained: 1) gastric emptying was delayed in NOD mice with a duration of diabetes of 28-35 days; 2) SGES was able to significantly increase gastric emptying in both diabetic mice and diabetic gastroparetic mice; and 3) the excitatory effect of SGES was completely blocked by atropine. SGES accelerates gastric emptying in NOD mice with diabetic gastroparesis. The effect of SGES on gastric emptying is mediated via the cholinergic pathway. These findings suggest that SGES may have a therapeutic potential for treating patients with diabetic gastroparesis.
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Affiliation(s)
- Geng-Qing Song
- Veterans Research and Education Foundation, Veterans Affairs Medical Center, Oklahoma City, Oklahoma 73104, USA
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171
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Song GQ, Hou X, Sun Y, Yang B, Qian W, Chen JDZ. Effects of retrograde gastric electrical stimulation with pulse trains on gastric emptying of solids and plasma hormones in dogs. Am J Surg 2007; 194:122-7. [PMID: 17560923 DOI: 10.1016/j.amjsurg.2006.12.036] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2006] [Revised: 12/13/2006] [Accepted: 12/13/2006] [Indexed: 02/04/2023]
Abstract
BACKGROUND Retrograde gastric electrical stimulation (RGES) is proposed as a novel therapy for obesity. However, mechanisms of RGES are not fully investigated. The aim of this study was to investigate the effects of RGES with trains of pulses on gastric slow waves, gastric emptying of solids, and plasma concentrations of satiety-related peptides and glucose. METHODS Seven female beagle dogs implanted with 4 pairs of gastric electrodes on the gastric serosa were studied (control and RGES). Gastric emptying, gastric slow waves, and signs were recorded in each session. Plasma leptin, insulin, glucagons, and glucose were also measured. RESULTS RGES with pulse trains (a pulse width of 2 milliseconds) significantly decreased gastric emptying of solids and plasma insulin but has no effect on plasma leptin, glucagons, and glucose. CONCLUSION Acute gastric electrical stimulation with pulse trains is able to decrease gastric emptying of solids and plasma insulin but has no effects on plasma leptin, glucagons, and glucose.
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Affiliation(s)
- Geng-Qing Song
- Division of Gastroenterology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1307 Luoyu Road, Wuhan, P.R. 430074, China
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172
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Liu S, Xu J, Chen JD. Roles of putative neurotransmitters in the regulation of gastric and intestinal slow waves in conscious dogs. J Gastroenterol Hepatol 2007; 22:1044-50. [PMID: 17608850 DOI: 10.1111/j.1440-1746.2007.04916.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/09/2022]
Abstract
BACKGROUND AND AIMS Slow waves play an important role in controlling the frequency and propagation of gastrointestinal contractions. However, mechanisms involved in the modulation of slow wave activity in vivo are still unclear. In this study, the roles of different neurotransmitters in the regulation of gastrointestinal slow waves were investigated in conscious dogs. METHODS Female dogs implanted with electrodes in the stomach and the small bowel were used in a seven-session study. Gastrointestinal myoelectrical activity was recorded at baseline and after i.v. saline, atropine, atropine methyl nitrate, guanethidine, Nomega-nitro-L-arginine (L-NNA), ondansetron or naloxone. RESULTS Both atropine and atropine methyl nitrate induced tachygastria, bradygastria and arrhythmia. No difference was noted in the effects between atropine and atropine methyl nitrate. L-NNA increased the dominant frequency of small-intestinal slow waves but had no effect on gastric slow waves. Guanethidine, ondansetron and naloxone did not affect the dominant frequency, power or percentage of normal gastrointestinal slow waves. CONCLUSION Acetylcholine acting at muscarinic receptors seems to play an important role in the regulation of gastric slow waves. Nitric oxide may play a role in modulating intestinal slow waves but not gastric slow waves. Sympathetic pathways, 5-HT(3) receptors and opioid receptors (especially micro-opioid receptors) do not play a role in the regulation of gastric or intestinal slow waves under normal physiological conditions.
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Affiliation(s)
- Shi Liu
- Division of Gastroenterology, University of Texas Medical Branch, Galveston, Texas, USA
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173
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Qi H, Liu S, Chen JDZ. Dual pulse intestinal electrical stimulation normalizes intestinal dysrhythmia and improves symptoms induced by vasopressin in fed state in dogs. Neurogastroenterol Motil 2007; 19:411-8. [PMID: 17509023 DOI: 10.1111/j.1365-2982.2006.00889.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
To assess effects of dual pulse intestinal electrical stimulation (DPIES) on intestinal dysrhythmia and motility, and symptoms induced by vasopressin in conscious dogs. The study was performed in three postprandial sessions (control; vasopressin; DPIES) in six dogs with two pairs of electrodes chronically implanted on the serosal surface of the proximal jejunum and with a chronic duodenal fistula. A manometric catheter was advanced into the small intestine via the intestinal cannula. Motility and intestinal slow waves were recorded. Symptoms were assessed. During vasopressin infusion, the percentage of normal intestinal slow wave frequency was decreased (P < 0.01), reflected as a significant increase in the percentage of both bradygastria and tachygastria; the motility index decreased (P < 0.01) and the symptom score increased (P < 0.01). In the session of DPIES, the percentage of normal slow wave frequency was recovered (P < 0.05 vs vasopressin), attributed to a reduction in both bradyarrhythmia and tachyarrhythmia; the symptom score was reduced (P < 0.05 vs vasopressin); the motility index was not significantly increased. These results suggest that vasopressin induces intestinal dysrhythmia and emetic symptoms and inhibits intestinal motility. Dual pulse intestinal electrical stimulation is capable of improving intestinal dysrhythmia and emetic symptoms but not impaired intestinal motility induced by vasopressin.
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Affiliation(s)
- H Qi
- Division of Gastroenterology, University of Texas Medical Branch, Galveston, TX 77555, USA
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174
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Yin J, Ouyang H, Chen JDZ. Potential of intestinal electrical stimulation for obesity: a preliminary canine study. Obesity (Silver Spring) 2007; 15:1133-8. [PMID: 17495188 DOI: 10.1038/oby.2007.615] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
OBJECTIVE The aims of this study were to investigate the therapeutic potential of intestinal electrical stimulation (IES) for obesity. Experiments were performed to investigate the effects of IES on food intake, gastric tone, gastric accommodation, and its possible pathway. RESEARCH METHODS AND PROCEDURES Ten normal dogs and six dogs with truncal vagotomy were used in this study. Each dog was equipped with a gastric cannula for the measurement of gastric tone and accommodation by barostat and one pair of duodenal serosal electrodes for IES. The experiment on food intake was composed of both control session without IES and IES session after a 28-hour fast. The experiment on gastric tone and accommodation was performed in the fasting and fed states and composed of three sessions: control, IES, and IES with N(G)-nitro-l-arginine. RESULTS IES significantly reduced food intake in the normal dogs (459.0 vs. 312.6 grams, p < 0.001). The food intake was negatively correlated with the fasting gastric volume during IES. IES significantly decreased fasting gastric tone in the normal dogs reflected as a decrease in gastric volume (89.1 vs. 261.3 mL, p < 0.01), which was abolished by vagotomy and N(G)-nitro-l-arginine. DISCUSSION IES reduces food intake and inhibits gastric tone in the fasting state. The inhibitory effect of IES on gastric tone is mediated by both vagal and nitrergic pathway.
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Affiliation(s)
- Jieyun Yin
- Veterans Research and Education Foundation, Veterans Administration Medical Center, Oklahoma City, Oklahoma, USA
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175
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Abstract
Gastroparesis is a symptomatic disorder of the stomach characterized by slow or delayed gastric emptying. Diabetes and idiopathic factors account for over 60% of gastroparesis cases. Symptoms associated with delayed gastric emptying include nausea, vomiting, abdominal bloating and early satiety. Delayed gastric emptying due to gastroparesis is managed by dietary adjustments, prokinetic medications, avoidance of medications that retard gastric motor activity and optimizing glycemic control in diabetic patients. Electrical stimulation and gastric pacing are an evolving treatment option for patients who do not respond to standard medical therapy. This article provides a review of gastric motility, the etiologies of gastroparesis and therapeutic approaches to this disorder.
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Affiliation(s)
- Tauseef Ali
- Department of Internal Medicine, Section of Gastroenterology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73190, USA.
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176
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Sevcencu C. Gastrointestinal Mechanisms Activated by Electrical Stimulation to Treat Motility Dysfunctions in the Digestive Tract: A Review. Neuromodulation 2007; 10:100-12. [DOI: 10.1111/j.1525-1403.2007.00098.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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177
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Sevcencu C. A Review of Electrical Stimulation to Treat Motility Dysfunctions in the Digestive Tract: Effects and Stimulation Patterns. Neuromodulation 2007; 10:85-99. [DOI: 10.1111/j.1525-1403.2007.00097.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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178
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Liu W, Qiu T, McCallum RW, Lin Z. Robust propagation velocity estimation of gastric electrical activity by least mean p-norm blind channel identification. Med Biol Eng Comput 2007; 45:437-45. [PMID: 17375346 DOI: 10.1007/s11517-007-0172-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2006] [Accepted: 01/16/2007] [Indexed: 11/26/2022]
Abstract
The propagation of the gastric slow wave is one of the most important spatial characteristics of gastric electrical activity (GEA). The time delay estimation (TDE) is an effective approach to quantitatively assessing the propagation velocity of GEA. Traditional TDE analyses are developed under the condition reported that the background noise in GEA analysis is Gaussian distributed. Due to the effects of spikes and/or motion artifacts, the GEA obtained from gastric serosal electrodes often contains sharp transitions. This paper proposes robust time delay estimation based on least mean p-norm blind channel identification (BCILMP) under alpha-stable noise condition. Compared with the least mean square time delay estimation (LMSTDE), the BCILMP provides better performance in the impulsive noise environments. The robustness of the proposed method is demonstrated through computer simulations in both Gaussian and alpha-stable noise environments. The results of the propagation velocity of real data obtained from gastric serosal electrodes in gastroparetic patients show that the propagation velocity in gastroparetic patients is slower than in the normal subjects reported in the literature, and the slow-wave propagation is directed proximally to distally from the corpus toward the pylorus but not all the variability of the propagation velocity increases monotonously.
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Affiliation(s)
- Wenhong Liu
- School of Electronic and Information Engineering, Dalian University of Technology, Dalian, China
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179
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Characterization of T9-T10 spinal neurons with duodenal input and modulation by gastric electrical stimulation in rats. Brain Res 2007; 1152:75-86. [PMID: 17433808 DOI: 10.1016/j.brainres.2007.03.034] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2007] [Revised: 03/12/2007] [Accepted: 03/12/2007] [Indexed: 10/23/2022]
Abstract
Gastric electrical stimulation (GES) has been suggested as a therapy for patients with gastric motility disorders or morbid obesity. However, it is unclear whether GES also affects intestinal sensory and motor functions. Furthermore, little is known about intraspinal visceroreceptive transmission and processing for duodenal afferent information. The aims of this study were to characterize responses of thoracic spinal neurons to duodenal distension, to determine the afferent pathway and to examine the effects of GES on activity of these neurons. Extracellular potentials of single T9-T10 spinal neurons were recorded in pentobarbital anesthetized, paralyzed, ventilated male rats (n=19). Graded duodenal distension (DD, 0.2-0.6 ml, 20 s) was produced by water inflation of a latex balloon surgically placed into the duodenum. One pair of platinum electrodes (1.0-1.5 cm apart) was sutured onto the serosal surface of the lesser curvature of the stomach. GES with four sets of parameters was applied for one minute: GES-A (6 mA, 0.3 ms, 40 Hz, 2 s on, 3 s off), GES-B (6 mA, 0.3 ms, 14 Hz, 0.1 s on, 5 s off), GES-C (6 mA, 3 ms, 40 Hz, 2 s on, 3 s off) and GES-D (6 mA, 200 ms, 12 pulses/min). Results showed that 33/117 (28%) spinal neurons responded to noxious DD (0.4 ml, 20 s). Of these, 7 (6%) neurons had low-threshold responses to DD (<or=0.2 ml) and 26 (22%) had high-threshold responses to DD (>or=0.4 ml). DD-responsive spinal neurons were encountered more frequently in deeper (depth: 0.3-1.2 mm) than in superficial laminae (depth: <0.3 mm) of the dorsal horn (24/67 vs. 9/50, P<0.05). DD excited all 9 superficial neurons. In contrast, 20 deeper neurons were excited and 4 neurons were inhibited by DD. Activity of DD-responsive neurons was affected more frequently with GES-C (13/15, 87%) than GES-A (6/16, 38%), -B (3/15, 20%) and -D (5/14, 36%) (P<0.01). Bilateral cervical vagotomy did not significantly alter the effects of DD and GES on 5/5 neurons. Resiniferatoxin (2.0 microg/kg, i.v.), an ultrapotent agonist of transient receptor potential vanilloid receptor-1 (TRPV1), abolished DD responses and GES effects on all neurons examined in vagotomized rats. Additionally, 29/33 (88%) DD-responsive neurons received inputs from somatic receptive fields on the back, flank and medial/lateral abdominal areas. It was concluded that GES mainly exerted an excitatory effect on T9-T10 spinal neurons with duodenal input transmitted by sympathetic afferent fibers expressing TRPV1; spinal neuronal responses to GES were strengthened with an increased pulse width and/or frequency of stimulation; T9-T10 spinal neurons processed input from the duodenum and might mediate effects of GES on duodenal sensation and motility.
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180
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Abstract
The prevalence of obesity is growing, is driving an increase in the prevalence of diabetes, and is creating a major public health crisis in the United States. Lifestyle and behavior therapy rarely give durable weight loss. There are few medications approved for the treatment of obesity. Those that exist are limited in efficacy and using them in combination does not result in greater weight loss. Surgical treatments for obesity are effective and give durable weight loss, but are accompanied by measurable morbidity and mortality. Several pacing approaches are being tried and are an outgrowth of pacing for gastroparesis. The Transcend(R) pacemaker blocks vagal efferents and delays gastric emptying, giving a 40% loss of excess body weight, if certain screening procedures are employed. The Tantulus pacemaker is still in development but increases antral muscular contractions and delays gastric emptying by stimulation during the absolute refractory period. Weight loss has been 30% of excess body weight, and glycohemoglobin decreased 1.6% in a trial of obese type 2 diabetes. Stimulation to the subdiaphragmatic sympathetics, vagal nerve stimulation with or without unilateral vagotomy, and intestinal pacing are other approaches that are still being evaluated preclinically. Clearly a safe, effective, and durable treatment for obesity is desperately needed. Electrical pacing of the gastrointestinal tract is promising therapeutically, and because pacemakers work through different mechanisms, combining pacemaker treatments may be possible. Rapid progress is being made in the field of electrical stimulation as a treatment for obesity and even greater progress can be expected in the foreseeable future.
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Affiliation(s)
- Frank Greenway
- Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, Louisiana 70808, USA.
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181
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Liu W, Qiu T, Lin Z, McCallum RW. Estimation of propagation velocity of gastric electrical activity using LMSTDE. CONFERENCE PROCEEDINGS : ... ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL CONFERENCE 2007; 2005:5954-7. [PMID: 17281617 DOI: 10.1109/iembs.2005.1615847] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
The least mean square time delay estimate (LMSTDE) algorithm is independent of the prior knowledge of signals and noises. Under the LMS criterion, the best estimate is acquired by automatic adjusting related parameters. In this paper, we applied LMSTDE to estimate the propagation velocities of four-channel gastric myoelectrical recordings that were obtained from implanted gastric serosal electrodes in three gastroparetic patients. The performance of the method was investigated using computer simulations. The results of this paper showed that the average velocities in gastroparetic patients are slower than in normal subjects. The propagation of gastric slow wave is along the greater curvature from upper 1/3 of the corpus toward the pylorus but the variability of the propagation velocity does not increase monotonously.
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Affiliation(s)
- Wenhong Liu
- School of Electronic & Information Enguneering, Dalian University of Technology, Dalian, China.
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182
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Brody F, Nam A, Drenon E, Ali A, Soffer E. Laparoscopic Insertion of Gastric Electrodes for Electrical Stimulation. J Laparoendosc Adv Surg Tech A 2007; 17:1-6. [PMID: 17362169 DOI: 10.1089/lap.2006.0132] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Gastric electrical stimulation can provide symptomatic relief for patients with refractory gastroparesis. Traditionally, these wires are placed through a midline laparotomy. This paper describes and illustrates, in detail, the laparoscopic technique for successful implantation. Thirty-one consecutive patients from October 2003 to March 2005 underwent laparoscopic insertion of gastric stimulating wires for gastroparesis. Twenty-six patients were female. Four laparoscopic ports were used to insert a pair of electrodes. Anterior, cephalad retraction of the gastric wall is critical for accurate seromuscular placement of gastric leads. Intraoperative endoscopy was used to verify the seromuscular placement of the leads. Both leads were secured to a subcutaneous generator and electrical parameters were immediately established in the operating room. Patient demographics, operative details, and postoperative morbidities were recorded. All procedures were completed laparoscopically. The mean operative time was 114.4 +/- 20.9 minutes (range, 95-140). No perioperative mortality occurred. Two patients developed cellulitis at the generator site postoperatively and oral antibiotics were prescribed for one week postoperatively. No hardware was removed. Two patients had their generators repositioned due to pain at the pocket site. Gastric electrical stimulation is a novel treatment modality for patients with refractory gastroparesis and can be accomplished safely via laparoscopy. Laparoscopic insertion is successful even in patients with prior surgery and intact gastrointestinal tubes. Long-term follow-up and the current prospective multicenter trial continue to assess the efficacy of this treatment modality.
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Affiliation(s)
- Fred Brody
- Department of General Surgery, The George Washington University Medical Center, Washington, DC 20037, USA.
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183
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Abstract
OBJECTIVE Tachygastria is known to be associated with gastric hypomotility. This study investigated the effect of tachygastrial electrical stimulation (TES) on food intake and its effects on gastric motility. RESEARCH METHODS AND PROCEDURES Five experiments were performed to study the effects of TES on gastric slow waves, gastric tone, accommodation, and antral contractions, gastric emptying, acute food intake, and chronic food intake in dogs. RESULTS TES at tachygastrial frequencies induced tachygastria and reduced normal slow waves. TES significantly reduced gastric tone or induced gastric distention, impaired gastric accommodation, and inhibited antral contractions. TES significantly delayed gastric emptying. Acute TES reduced food intake but did not induce any noticeable symptoms. Chronic TES resulted in a 20% reduction in food intake, and the effect of TES was found to be related to specific parameters. DISCUSSION TES at the distal antrum results in a significant reduction in food intake in dogs, and this inhibitory effect is probably attributed to TES-induced reduction in proximal gastric tone, gastric accommodation, antral contractility, and gastric emptying. These data suggest a therapeutic potential of the specific method of TES for obesity.
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Affiliation(s)
- Jing Zhang
- Veterans Research Foundation, VA Medical Center, Oklahoma City, Oklahoma, USA
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184
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Xing JH, Chen JDZ. Gastric electrical stimulation with parameters for gastroparesis enhances gastric accommodation and alleviates distention-induced symptoms in dogs. Dig Dis Sci 2006; 51:2160-4. [PMID: 17078009 DOI: 10.1007/s10620-006-9212-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/25/2005] [Accepted: 12/18/2005] [Indexed: 12/20/2022]
Abstract
Gastric electrical stimulation (GES) improves symptoms in patients with gastroparesis. We sought to determine if stimulation at fundus with parameters used for gastroparesis could affect gastric accommodation and distention-induced symptoms in dogs. Nine dogs were implanted with a gastric cannula at the anterior stomach and 1 pair of stimulation electrodes in the fundus. Assessment of gastric accommodation and a series of gastric distention were performed using a barostat. Stimulation parameters were of short pulse trains of 14 Hz, 5 mA, 0.3 ms, and 0.1 s on, 5 s off. GES at fundus significantly decreased fasting gastric tone. Fasting gastric volume was significantly increased from 56.3+/-10.4 mL at baseline to 102.4+/-23.1 mL with stimulation (P=.011). Postprandial gastric accommodation was significantly enhanced with stimulation. The extent of accommodation increased from 249.3+/-39.9 mL in the control session to 325.8+/-25.1 mL with stimulation (P=.011). Symptom scores induced by balloon distention of the stomach were significantly lower during stimulation in comparison with those of baseline (P=.016). In conclusion, GES with parameters for gastroparesis enhances postprandial gastric accommodation and reduces visceral perception in normal dogs. This effect, if seen also in humans, may explain in part the symptomatic improvement associated with GES therapy in patients with gastroparesis.
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Affiliation(s)
- J H Xing
- Veterans Research Foundation, Oklahoma City, Oklahoma, USA
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185
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Ouyang H, Yin J, Chen JDZ. Gastric or intestinal electrical stimulation-induced increase in gastric volume is correlated with reduced food intake. Scand J Gastroenterol 2006; 41:1261-6. [PMID: 17060118 DOI: 10.1080/00365520600708008] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
OBJECTIVE Satiation has recently been shown to be associated with gastric volume or gastric tone. Electrical stimulation has been shown to reduce food intake and increase gastric volume, or reduce gastric tone. The aim of this study was to investigate the correlation between gastric or intestinal electrical stimulation (GES/IES)-induced increase in gastric volume and food intake. MATERIAL AND METHODS GES/IES was performed on 14 dogs implanted with electrodes and a gastric cannula. Food intake was measured and gastric volume was assessed using barostat with or without GES/IES. RESULTS Food intake was correlated to weight (r = 0.62, p = 0.02) as well as the fasting gastric volume (r = 0.59, p = 0.02). GES/IES reduced food intake (240.8 versus 445.0 g, p < 0.005) and increased gastric volume in the fasting state (263.4 versus 74.4 ml, p < 0.0001). Reduced food intake was correlated to the preprandial gastric volume (r = - 0.58, p = 0.02) and postprandial increase in gastric volume with GES/IES (r = 0.56, p = 0.03). CONCLUSIONS. GES/IES reduces food intake and increases gastric volume measured by barostat. The GES/IES-induced increase in gastric volume (or reduced gastric tone) is correlated with reduced food intake during GES/IES.
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Affiliation(s)
- Hui Ouyang
- Transneuronix and Veterans Research & Education Foundation, Oklahoma City, Oklahoma, USA
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186
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Qin C, Chen JDZ, Zhang J, Foreman RD. Modulatory effects and afferent pathways of gastric electrical stimulation on rat thoracic spinal neurons receiving input from the stomach. Neurosci Res 2006; 57:29-39. [PMID: 17046091 PMCID: PMC1855190 DOI: 10.1016/j.neures.2006.09.003] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2006] [Revised: 08/29/2006] [Accepted: 09/07/2006] [Indexed: 01/17/2023]
Abstract
Gastric electrical stimulation (GES) has been suggested as a potential therapy for patients with obesity or gastric motility disorders. The aim of this study was to investigate the spinal mechanism of GES effects on gastric functions. Extracellular potentials of single spinal (T9-T10) neurons were recorded in pentobarbital anesthetized, paralyzed, ventilated male rats (n=19). Gastric distension (GD) was produced by air inflation of a balloon. One pair of platinum electrodes (1.0-1.5cm apart) was sutured onto the serosal surface of the lesser curvature of the stomach. GES with four sets of parameters was applied for 1min: GES-A (6mA, 0.3ms, 40Hz, 2s on, 3s off), GES-B (6mA, 0.3ms, 14Hz, 0.1s on, 5s off), GES-C (6mA, 3ms, 40Hz, 2s on, 3s off), GES-D (6mA, 200ms, 12pulses/min). 62/158 (39%) spinal neurons responded to GD (20, 40, 60mmHg, 20s. Most GD-responsive neurons (n=43) had excitatory responses; the remainder had inhibitory (n=12) or biphasic responses (n=7). GES-A, -B, -C and -D affected activity of 12/33 (36%), 4/31 (13%), 22/29 (76%) and 13/30 (43%) GD-responsive neurons, respectively. Bilateral cervical vagotomy did not significantly alter mean excitatory neuronal responses to GD (n=5) or GES (n=6). Resiniferatoxin (2.0microg/kg, i.v.), an ultrapotent agonist of vanilloid receptor-1, abolished excitatory responses to GD and GES in 4/4 neurons recorded in vagotomized rats. The results suggested that GES mainly had an excitatory effect on T9-T10 spinal neurons with gastric inputs; neuronal responses to GES were strengthened with stimulation at an increased pulse width and/or number of pulses. The modulatory effect of GES involved thoracic spinal (sympathetic) afferent fibers containing vanilloid receptor-1.
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Affiliation(s)
- Chao Qin
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73190, USA.
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187
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Abstract
BACKGROUND Over the past 20 years, gastric electrical stimulation has received increasing attention among researchers and clinicians. AIM To give a systematic review on the effects, mechanisms and applications of gastric electrical stimulation. METHODS Medline was used to identify the articles to be included in this review. Key words used for the search included gastric electrical stimulation, gastric pacing, electrical stimulation, stomach, gastrointestinal motility, central nervous system, gastroparesis, nausea and vomiting; obesity and weight loss. Combinational uses of these keywords were made to identify relevant articles. Most of the articles included in this review ranged from 1985 to 2006. RESULTS Based on the general search, the review was structured as follows: (i) peripheral and central effects and mechanisms of gastric electrical stimulation; (ii) clinical applications of gastric electrical stimulation for gastroparesis and obesity and (iii) future development of gastric electrical stimulation. CONCLUSIONS Great progress has been made during the past decades. Gastric electrical stimulation has been shown to be effective in normalizing gastric dysrhythmia, accelerating gastric emptying and improving nausea and vomiting. Implantable device has been made available for treating gastroparesis as well as obesity. However, development of a new device and controlled clinical studies are required to further prove clinical efficacy of gastric electrical stimulation.
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Affiliation(s)
- J Zhang
- Veterans Research and Education Foundation, VA Medical Center, Oklahoma City, OK, USA
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188
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Yin J, Hou X, Chen JDZ. Roles of interstitial cells of Cajal in intestinal transit and exogenous electrical pacing. Dig Dis Sci 2006; 51:1818-23. [PMID: 16957993 DOI: 10.1007/s10620-006-9313-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/22/2005] [Accepted: 03/12/2006] [Indexed: 12/27/2022]
Abstract
The aims of this study were to investigate the role of interstitial cells of Cajal (ICCs) on small intestinal transit and its responses to exogenous pacing in W/W(v) mice. Eleven W/W(v) mice and their controls implanted with four pairs of gastrointestinal electrodes were used for testing the entrainment of slow waves. Another 20 W/W(v) mice and their controls equipped with a duodenal catheter and one pair of intestinal electrodes were used to test small intestinal transit represented by the geometric center (GC). Results were as follows. (1) The effect of pacing on slow wave frequency was sustained only in controls, and not in W/W(v) mice. (2) Both gastric and intestinal slow waves were completely entrained in controls and W/W(v) mice. Higher energy was required for pacing the stomach than the small intestine. (3) There was no significant difference in small intestinal transit between the controls and the W/W(v) mice (GC: 5.4 vs. 5.5). (4) Pacing showed no effects on small intestinal transit in either wild-type (GC: 5.4 vs. 5.6) or W/W(v) mice (GC: 5.5 vs. 5.7). We conclude that myenteric ICCs may not play an important role in the regulation of small intestinal transit in conscious mice. Gastric and intestinal pacing can be achieved without ICCs.
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Affiliation(s)
- Jieyun Yin
- Veterans Research and Education Foundation, VA Medical Center Transneuronix Inc, Oklahoma City, Oklahoma, USA
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Caprino P, Fagotti A, Missere M, Fanfani F, Scambia G. Severe prolonged gastroparesis after cytoreductive surgery in an advanced ovarian cancer patient. Int J Gynecol Cancer 2006; 16:1936-9. [PMID: 17009995 DOI: 10.1111/j.1525-1438.2006.00719.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
Number and type of complications after ovarian cancer surgery can vary greatly according to both the patient's characteristics, and the extension and type of surgery. Current literature lacks in mentioning specific gastrointestinal side effects, which could be evidenced during the early postoperative course of patients submitted to major gynecological oncologic surgery. A severe gastroparesis prolonged for 2 months after cytoreductive surgery in an advanced ovarian cancer patient was successfully treated with conservative multidrug therapy. Gastroparesis has to be enumerated as a rare but possible event after major gynecological oncologic surgery. A conservative management involving decompressive nasogastric tube, nutritional support, antiemetic drugs, prokinetic drugs is suggested, while surgical therapy is only recommended in a very small subset of unmanageable patients.
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Affiliation(s)
- P Caprino
- Division of Surgical Oncology, Catholic University of the Sacred Heart, Campobasso, Italy
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190
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Joly F, Amiot A, Coffin B, Lavergne-Slove A, Messing B, Bouhnik Y. Pseudo-obstruction intestinale chronique. ACTA ACUST UNITED AC 2006; 30:975-85. [PMID: 17075444 DOI: 10.1016/s0399-8320(06)73359-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Chronic intestinal pseudo-obstruction (CIPO) is a disease characterized by episodes resembling mechanical obstruction in the absence of organic, systemic, or metabolic disorders. Pseudo-obstruction is an uncommon condition and can result from primary (40%) or secondary (60%) causes. The most common symptoms are nausea, vomiting, abdominal distension, abdominal pain and constipation or diarrhea. These symptoms are usually present many years before CIPO diagnosis. They can lead to severe electrolyte disorders and malnutrition. Principles for management of patients with CIPO are: to establish a correct clinical diagnosis in excluding mechanical obstruction; to perform a symptomatic and physiologic assessment of the gastrointestinal tract involved; to look for extra-intestinal manifestations, especially for myopathy and neuropathy; to discuss in some cases a surgery for full-thickness intestinal biopsies, and/or a neuromuscular biopsy in case of mitochondrial cytopathy suspicion. The management is primarily focused on symptom control and nutritional support to prevent weight loss and malnutrition. Treatment of CIPO includes prokinetic agents which may help to reduce gastrointestinal symptoms Courses of antibiotics may be needed in patients with symptoms suggestive of bacterial overgrowth. When necessary, enteral nutrition is preferred. In carefully selected patients, feeding jejunostomy with or without decompression gastrostomy may be tried. Long term parenteral nutrition should be reserved for patients who can not tolerate enteral nutrition. Intestinal transplantation can be discussed in selected patients.
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Affiliation(s)
- Francisca Joly
- Service de Gastroentérologie et d'Assistance nutritive, Hôpital Beaujon, 100 Boulevard du Général Leclerc, Clichy-la-Garenne, 92110 Clichy cedex
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191
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Sanmiguel CP, Casillas S, Senagore A, Mintchev MP, Soffer EE. Neural gastrointestinal electrical stimulation enhances colonic motility in a chronic canine model of delayed colonic transit. Neurogastroenterol Motil 2006; 18:647-53. [PMID: 16918729 DOI: 10.1111/j.1365-2982.2006.00783.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Neural gastrointestinal electrical stimulation (NGES) induces sequential contractions and enhances emptying in acute canine gastric and colonic models. This study was set to determine (i) the effect of NGES in a chronic canine model of delayed colonic transit and (ii) possible mechanism of action. Four pairs of electrodes were implanted in the distal colon of nine mongrel dogs. Delayed colonic transit was induced by diphenoxylate/atropine and alosetron. Transit was fluoroscopically determined by the rate of evacuation of radiopaque markers, and was tested twice in each dog, in random order, on and off stimulation. Two stimulation sequences, separated by 1 min, were delivered twice a day via exteriorized electrodes. Colonic manometry during stimulation was performed before and after intravenous (i.v.) injection of 1 mg of atropine. Complete evacuation of all markers was significantly shortened by NGES, from 4 days to 2 days, interquartile range 3-4 days vs 2-3 days, respectively, P = 0.016. NGES induced strong sequential contractions that were significantly diminished by atropine: 190.0 +/- 14.0 mmHg vs 48.7 +/- 19.4 mmHg, respectively (P < 0.001). NGES induces strong sequential colonic contractions and significantly accelerates movement of content in a canine model of delayed colonic transit. The effect is atropine sensitive.
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Affiliation(s)
- C P Sanmiguel
- Department of Gastroenterology, Cleveland Clinic Foundation, Cleveland, OH, USA
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192
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Yin J, Chen J. Inhibitory effects of gastric electrical stimulation on ghrelin-induced excitatory effects on gastric motility and food intake in dogs. Scand J Gastroenterol 2006; 41:903-9. [PMID: 16803688 DOI: 10.1080/00365520500527391] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
OBJECTIVE To investigate the effects of ghrelin on food intake, gastric motility and whether gastric electrical stimulation (GES) is capable of reversing these effects of ghrelin in dogs. MATERIAL AND METHODS Seven healthy dogs were equipped with a gastric cannula and electrodes for the measurement of antral motility and gastric myoelectrical activity (GMA). Both food intake and gastric motility studies were performed in three sessions (control, ghrelin, 20 microg and ghrelin plus GES) in randomized order, respectively. After a 28-h fast, the animals were provided with unlimited solid food for 1.5 h, 30 min after saline or ghrelin injection. Recordings of antral contractions and GMA in each session were recorded for 30 min at baseline and 45 min after ghrelin/saline injection in the fasting state. GES was performed throughout the experiment initiated 30 min prior to the injection. RESULTS 1) Ghrelin significantly increased food intake from 475.6+/-75.5 g in the controls to 535.9+/-90.3 g with ghrelin (p=0.04); this excitatory effect was reversed by GES. 2) Ghrelin significantly increased the motility index from 8.6+/-1.6 in the controls to 16.1+/-2.4 with ghrelin (p=0.01) and this effect was also reversed by GES. 3). There were no effects of ghrelin on GMA. CONCLUSIONS Ghrelin induces antral contractions and increases food intake. GES is capable of blocking these excitatory effects of ghrelin. These findings suggest that GES may inhibit the resistant effect of ghrelin on weight loss.
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Affiliation(s)
- Jieyun Yin
- Veterans Research and Education Foundation, VA Medical Center and Transneuronix Inc., Oklahoma City, Oklahoma, and Division of Gastroenterology, University of Texas Medical Branch, Galveston 77555-0632, USA
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193
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Familoni BO, Abell TL, Bhaskar SK, Voeller GR, Blair SR. Gastric electrical stimulation has an immediate antiemetic effect in patients with gastroparesis. IEEE Trans Biomed Eng 2006; 53:1038-46. [PMID: 16761831 DOI: 10.1109/tbme.2006.873395] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
BACKGROUND Electrical stimulation has been successfully employed to treat diseases involving electro-pathology in the heart, skeletal muscles, and the brain, but not in the GI tract. AIM This study examined the clinical feasibility and efficacy of GES in treating patients with severe gastroparesis. METHODS Nausea, vomiting, GEA, and liquid and solid gastric emptying were monitored in eleven patients with refractory gastroparesis at baseline and after one week of continuous electrical stimulation administered at 12 cycles/min. Eight patients were subsequently implanted with permanent stimulation devices. Follow-up studies were conducted after 1, 3, 6, and 12 mo. of stimulation. RESULTS After one week of stimulation, patients' quantified symptoms of nausea and vomiting decreased significantly, and liquid emptying and GEA improved. This improvement was maintained over time in the patients who continued to receive stimulation. Emptying of solids showed progressive improvement that became significant after 3 mo. The three patients who did not receive stimulation after the trial period showed significantly higher symptoms at 12 mo. CONCLUSION This paper demonstrates that GES at a frequency of 12 cycles/min has an immediate antiemetic effect, followed by an improvement in disordered gastric emptying.
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Affiliation(s)
- Babajide O Familoni
- Department of Electrical Engineering, The University of Memphis, TN 38152, USA.
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194
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Abstract
Among all classes of therapies for morbid obesity-behavioral, drugs, devices, and surgery-devices for electrical stimulation are a relatively new approach. This article reviews the history of electrical therapies for the gastrointestinal tract with an emphasis on the development of stimulation for obesity. Based on similar animal work, electrical stimulation of the gastrointestinal tract has been applied to treat morbid obesity much in the way it has been used to treat nausea and vomiting. The current status of gastrointestinal electrical stimulation for the treatment of morbid obesity is reviewed, with an emphasis on human studies. The physics of electrical stimulation and the possible mechanism of stimulation in the gastrointestinal tract, including for the treatment of morbid obesity, are also discussed. Future work on stimulation for obesity offers the opportunity for better understanding of possible mechanisms of action.
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Affiliation(s)
- Thomas L Abell
- Division of Digestive Diseases, University of Mississippi Medical Center, Jackson, Mississippi 39216, USA.
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195
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Jalilian E, Onen D, Neshev E, Mintchev MP. Implantable neural electrical stimulator for external control of gastrointestinal motility. Med Eng Phys 2006; 29:238-52. [PMID: 16675282 DOI: 10.1016/j.medengphy.2006.03.009] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2005] [Revised: 03/13/2006] [Accepted: 03/22/2006] [Indexed: 10/24/2022]
Abstract
Functional electrical stimulation has been suggested as a possible avenue for treating a variety of gastrointestinal motility-related disorders such as gastroparesis, chronic constipation and morbid obesity. The aims of the present study were to design a radio-frequency controlled multi-channel implantable neural gastrointestinal electrical stimulator and test it in an acute canine model. The stimulation parameters can be reprogrammed after implantation, allowing the execution of parametric studies and the investigation of their efficacy in producing controlled gastrointestinal contractions. Bipolar pulse trains of 50Hz frequency, 8-16V(pp) amplitude, 10-100% duty cycle, 1-120s duration, and 2s to 1h pause between successive stimulation sessions were delivered to the stomachs of nine dogs. The resulting contractions were measured by force transducers and digitally recorded on a personal computer. The acute studies confirmed the effectiveness of electrical stimulation in producing invoked gastric contractile activity under the control of the implantable neurostimulator.
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Affiliation(s)
- Ehsan Jalilian
- Department of Electrical and Computer Engineering, University of Calgary, Alta., Canada
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196
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Song G, Hou X, Yang B, Sun Y, Liu J, Qian W, Chen JDZ. Efficacy and efficiency of gastric electrical stimulation with short pulses in the treatment of vasopressin-induced emetic responses in dogs. Neurogastroenterol Motil 2006; 18:385-91. [PMID: 16629866 DOI: 10.1111/j.1365-2982.2006.00758.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The aim of this study was to determine the most effective and efficient anti-emetic parameters of short-pulse gastric electrical stimulation (GES) in dogs. Seven female beagle dogs implanted with four pairs of gastric electrodes were studied in eight randomized sessions (saline, vasopressin, and six GES sessions with different parameters). Each session consisted of four 20-min recordings of gastric slow waves and symptoms. In sessions 1 and 2, saline and vasopressin, respectively, were infused during the second 20-min period. The protocol of the other six sessions was the same as session 2 except that GES was continuously applied. It was found that: (1) vasopressin induced gastric dysrhythmia and emetic response (P < 0.01, anova); (2) short-pulse GES with a frequency of 14 or 40 Hz and pulse width of 0.1 or 0.3 ms, but not 0.6 ms was able to reduce symptoms induced by vasopressin; (3) short-pulse GES with a pulse width of 0.3 ms was the most effective in preventing vasopressin-induced symptoms; (4) none of the tested GES methods improved vasopressin-induced gastric dysrhythmia. We conclude that vasopressin induces gastric dysrhythmia and symptoms. Short-pulse GES with a pulse width of 0.3 ms and frequency of 14 Hz is most effective and efficient in preventing vasopressin-induced emetic responses in dogs.
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Affiliation(s)
- G Song
- Division of Gastroenterology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
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197
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Abstract
Gastroparesis refers to chronically abnormal gastric motility characterized by symptoms suggestive of mechanical obstruction and delayed gastric emptying in the absence of mechanical obstruction. It may be idiopathic or attributable to neuropathic or myopathic abnormalities, such as diabetes mellitus, postvagotomy, postviral infection, and scleroderma. Dietary and behavioral modification, prokinetic drugs, and surgical interventions have been used in managing patients with gastroparesis. Although mild gastroparesis is usually well managed with these treatment options, severe gastroparesis may be very difficult to control and may require referral to a specialist center if symptoms are intractable despite pharmacological therapy and dietetic support. New advances in drug therapy, botulinum toxin injection, and gastric electrical stimulation techniques have been introduced and might provide new hope to patients with refractory gastroparesis. This article critically reviews the advances in the field from the perspective of the clinician.
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Affiliation(s)
- Moo-In Park
- Department of Internal Medicine, College of Medicine, Kosin University, Busan, Korea
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198
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Abell TL, Bernstein RK, Cutts T, Farrugia G, Forster J, Hasler WL, McCallum RW, Olden KW, Parkman HP, Parrish CR, Pasricha PJ, Prather CM, Soffer EE, Twillman R, Vinik AI. Treatment of gastroparesis: a multidisciplinary clinical review. Neurogastroenterol Motil 2006; 18:263-83. [PMID: 16553582 DOI: 10.1111/j.1365-2982.2006.00760.x] [Citation(s) in RCA: 261] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
This clinical review on the treatment of patients with gastroparesis is a consensus document developed by the American Motility Society Task Force on Gastroparesis. It is a multidisciplinary effort with input from gastroenterologists and other specialists who are involved in the care of patients with gastroparesis. To provide practical guidelines for treatment, this document covers results of published research studies in the literature and areas developed by consensus agreement where clinical research trials remain lacking in the field of gastroparesis.
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Affiliation(s)
- T L Abell
- University of Mississippi Medical Center, Jackson, USA
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199
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Liu J, Hou X, Song G, Cha H, Yang B, Chen JDZ. Gastric electrical stimulation using endoscopically placed mucosal electrodes reduces food intake in humans. Am J Gastroenterol 2006; 101:798-803. [PMID: 16494587 DOI: 10.1111/j.1572-0241.2006.00493.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
BACKGROUND Implantable gastric stimulation (IGS) has been proposed for treating obesity. The aim of this study was to investigate the effects of temporary mucosal electrical stimulation on water and food intake as well as gastric emptying in healthy humans. METHODS The study was designed to study the effects of temporary gastric electrical stimulation (GES) on symptoms, gastric accommodation, food intake, and gastric emptying. It was performed in 12 healthy volunteers on 3 consecutive days. GES was performed using mucosal electrodes endoscopically placed in the fundus. RESULTS The amount of maximum water intake was reduced with GES (894 +/- 326 mL) compared with sham-GES (1,093 +/- 417 mL, p = 0.01). The food intake was also reduced with GES (p = 0.012). In comparison with sham stimulation, GES delayed gastric emptying during the first 45 min after the meal but not during the remaining time. GES with parameters effective in reducing water and food intake and delaying gastric emptying did not induce significant dyspeptic symptoms, compared with sham stimulation. CONCLUSIONS GES using temporary mucosal electrodes decreases food intake as well as maximum intake of water, and has a tendency of delaying gastric emptying. It may have a potential application for the treatment of obesity.
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Affiliation(s)
- Jun Liu
- Division of Gastroenterology, Union Hospital, Tongji Medical College, Huazhong Science and Technology University, Wuhan, Republic of China
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200
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Liu J, Qiao X, Chen JDZ. Therapeutic potentials of a novel method of dual-pulse gastric electrical stimulation for gastric dysrhythmia and symptoms of nausea and vomiting. Am J Surg 2006; 191:255-61. [PMID: 16442956 DOI: 10.1016/j.amjsurg.2005.11.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2005] [Revised: 11/21/2005] [Accepted: 11/21/2005] [Indexed: 10/25/2022]
Abstract
BACKGROUND The aims of this study were to investigate the effects and mechanisms of a novel method of gastric electrical stimulation on the prevention of vasopressin-induced emetic response and gastric dysrhythmias. METHODS Fifteen dogs (10 normal, 5 vagotomized) chronically implanted with gastric serosal electrodes were used in a 3-session study (vasopressin, vasopressin plus 2-channel stimulation [DCS], and vasopressin plus dual-pulse stimulation [DPS]). RESULTS Vasopressin induced gastric dysrhythmias and motion sickness-like symptoms (P < .05) and these effects were blocked partially with vagotomy. Both methods of DCS and DPS were capable of preventing vasopressin-induced gastric dysrhythmias (P < .05) and motion sickness-like symptoms (P < .05). The antiemetic effects of the proposed methods of DCS and DPS were abolished by vagotomy but their antidysrhythmic effects were not blocked by vagotomy. CONCLUSIONS DCS and DPS are able to reduce vasopressin-induced gastric dysrhythmia and symptoms of nausea and vomiting. The vagal pathway is involved in the antiemetic effect but not the antidysrhythmic effect of the proposed methods of stimulation.
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Affiliation(s)
- Jinsong Liu
- Division of Gastroenterology, University of Texas Medical Branch, GI Research, Route 0632, Room 221, Microbiology Building, 1108 The Strand, Galveston, TX 77555-0632, USA
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