Gastric Emptying in Response to Neural Gastric Electric Stimulation in an Acute Porcine Model

Delayed gastric conduit emptying (DGCE) is a common complication following esophagectomy-associated gastric conduit surgery and is often resistant to conventional treatments. Neural gastric electrical stimulation (NGES) is a potential approach to managing DGCE by generating propulsive gastric contractions through timed bursts of high-frequency, multisite stimulation. This study evaluates the efficacy of NGES in increasing gastric emptying in an acute porcine vagally denervated postsurgical conduit.

Six anaesthetized pigs underwent a staged interventions to assess whether gastric emptying at baseline, after bilateral truncal vagotomy, and after creation of a gastric conduit was accelerated by anterior-plus-posterior (A-plus-P) NGES or anterior-only (A-only) NGES. NGES was delivered through sequential (proximal-to-distal) activation of multiple gastric serosal electrode pairs to induce coordinated peristalsis. Liquid gastric emptying was measured by direct effluent collection, and myoelectrical activity was recorded by the same electrodes. Percentage gastric emptying was compared across conditions using repeated-measures analysis.

Vagotomy reduced 15-minute gastric emptying from 30.8 ± 26.0% to 7.9 ± 8.6% (p < 0.01). NGES improved emptying after vagotomy to 48.8 ± 28.3% with A-plus-P electrode stimulation (p = 0.004) and 48.0 ± 27.4% with A-only electrode stimulation (p = 0.003). Gastric tubularization independently increased emptying to 70.0 ± 21.5% (p = 0.006 vs the vagotomized whole stomach), with a peak of 96.3 ± 6.5% when tubularization was combined with A-only NGES.

NGES, using gastric surface electrodes, effectively increases gastric emptying after acute vagotomy, with A-only electrode stimulation achieving comparable efficacy to A-plus-P stimulation. These findings position NGES as a promising therapy for DGCE and other refractory gastric motility disorders, supporting progression to chronic animal studies to assess long-term efficacy and safety.