Microprocessor-controlled movement of solid gastric content using sequential neural electrical stimulation

Background & Aims: Gastric electrical stimulation has been attempted for years without much success. The aim of this study was to determine if movement of solid gastric content could be achieved using microprocessor-controlled sequential electrical stimulation. Methods: The study was performed on 9 anesthetized dogs. The dogs underwent laparotomy, pyloroplasty, and implantation of 4-6 sets of bipolar stainless-steel wire electrodes. Each set consisted of 2-6 electrodes (10 x 0.25 mm, 3 cm apart) implanted circumferentially. The stomach was filled with solid food mixed with plastic pellets, and the process of gastric emptying was monitored. Artificial contractions were produced using microprocessor-controlled phase-locked bipolar trains of 50-Hz rectangular voltage with flexible amplitudes. Results: Using the above stimulating parameters, we were able to produce circumferential gastric contractions that were artificially propagated distally by embedding and phase-locking the stimulating voltage. The number of expelled pellets after the stimulation sessions was significantly higher than the number of pellets emptied during the nonstimulation sessions (P < 0.01). Conclusions: Microprocessor-controlled electrical stimulation produced artificial peristalsis and markedly accelerated the movement of solid gastric content.