In silico study of luminal transport of bile salts from the duodenum to the gastric mucosa: Role of small intestinal peristalsis.

This article focuses on a mathematical and computational investigation of bile salt transport in the antropyloroduodenal (APD) segment of the small intestine, emphasizing the role of duodenal motility patterns in biliary reflux, a factor implicated in gastric carcinoma progression. Using a power law fluid model and lubrication approximation, the study analyzes how various peristaltic wave parameters—such as wave type (antegrade, retrograde, stationary), occlusion, wavelength, velocity, and pyloric motility—affect bile transport and particle transit. Results indicate that increased occlusion and wave speed enhance bile movement toward the stomach, while pyloric motility imposes hydrodynamic resistance scaling inversely with the fourth power of the pyloric radius, influencing reflux dynamics. Particle tracing reveals elliptical and oscillatory motions dependent on wave propagation and pyloric activity, highlighting the complex interplay between intestinal biomechanics and bile reflux. The model’s findings contribute to understanding the mechanistic basis of duodenogastric reflux and its potential pathological consequences, though limitations exist at high occlusion levels due to model assumptions.