Driving Gastric Electrical Activity with Electrical Stimulation

Abstract

Gastric electrical stimulation (GES) therapy is generating a lot of interest, but it is still investigational. Its efficacy in driving gastric electrical activity and improving motility, and the ideal frequency for bringing this about are still controversial. In this study, a rule-based computer model of tissue electrical response to stimulation was developed to examine the interaction between tissue electrical refractoriness and the onset of tissue activation. The results were compared to response to GES in 8 dogs implanted with electrodes and strain gauges and stimulated at frequencies ranging from 3 to 30 cycles/min. Simulated electrical control activity at an intrinsic frequency of 5/min was entrained from 2.0 cycles/min to 7.92 cycles/min. The regularity of the ECA elicited by stimulation depended on the number of pulses injected. Electrical stimulation in canine stomach entrained the native electrical control activity from a baseline average of 5.14 +/- 0.32 cycles/min up to 9.2 cycles/min. Contractile response to stimulation at 20-30 cycles/min were significantly higher (p < 0.05). Computer simulation of GES may be a useful tool to complement and reduce some of the costs associated with empirical studies of gastric electrical stimulation in establishing its possible use in treating drug refractory gastroparesis.

Gastric Electrical Stimulation Has an Immediate Antiemetic Effect in Patients With Gastroparesis

“…Placement of transmucosal electrodes as described here carries a small risk of bleeding and infection at the implantation site, i.e., the usual risks associated with standard endoscopy. In patients without a PEG, similar temporary stimulation can be achieved by placing electrodes at laparoscopy [36] and analytical method can be used to a limited extent [38].…”

Electrical Stimulation as Treatment for Obesity and Diabetes

“…40 Another study in dogs demonstrated that one can entrain the gastric slow wave and vary their frequencies between two and nine cycles per minute from the normal five per minute normally seen in dogs. 41 Based on these animal studies demonstrating inhibition of gastric contractions and delayed gastric emptying, temporary pacing was evaluated in normal human volunteers. Retrograde pacing with a mucosal electrode placed endoscopically on the greater curvature of the stomach 5 cm above the pyolorus was performed in 12 normal volunteers.…”

Manipulation of food intake and weight dynamics using retrograde neural gastric electrical stimulation in a chronic canine model

“…13,14 Gastric electrical stimulation Implantable gastric stimulation is a less invasive bariatric procedure which utilizes gastric electrical stimulation (GES). [15][16][17] Three techniques have been commonly employed for electrically stimulating the stomach: gastric pacing, 15,18 low-energy high-frequency stimulation 19 and neural GES (NGES). [20][21][22] In gastric pacing, which can be regarded as a lowenergy, low-frequency stimulation technique, the stomach is stimulated at or slightly above its natural electrophysiological frequency, entraining gastric electrical activity also known as Ôslow wavesÕ.…”

“…Implantable gastric stimulation is a less invasive bariatric procedure which utilizes gastric electrical stimulation (GES) 15–17 . Three techniques have been commonly employed for electrically stimulating the stomach: gastric pacing, 15,18 low‐energy high‐frequency stimulation 19 and neural GES (NGES) 20–22 …”