The effect of terminal ileal triglyceride infusion on gastroduodenal motility and the intragastric distribution of a solid meal.

The infusion of triglyceride emulsions into the terminal ileum in concentrations that approximate those found in malabsorption results in the slowing of gastric emptying. The aim of this study was to characterize the changes in gastroduodenal motility responsible for this effect. Antropyloroduodenal pressures in 8 healthy volunteers were recorded with a manometric assembly incorporating a sleeve sensor across the pylorus and side holes in the antrum and duodenum. Each subject ingested a 100-g, 99m Tc-labeled solid meal; when approximately 25% of the meal had emptied from the stomach, a triglyceride emulsion (20% Intralipid) was infused into the terminal ileum at 1 ml/min for 45 min. Gastric emptying slowed markedly 15-30 min after the start of the lipid infusion (p = 0.01), and there was retrograde movement of the solid meal from the distal to the proximal portion of the stomach. During lipid infusion, there was a decrease in antral (p = 0.01), duodenal (p less than 0.05), and propagated antropyloroduodenal pressure waves (p less than 0.05) and an increase in isolated pyloric pressure waves (p less than 0.05). The rate of gastric emptying correlated with antral pressure waves (r = 0.92, p less than 0.001), duodenal pressure waves (r = 0.80, p less than 0.01), and propagated pressure waves (r = 0.88, p = 0.0025) and correlated inversely with the number of isolated pyloric pressure waves (r = -0.60, p = 0.05). The changes in antral, pyloric, and duodenal motility and the intragastric redistribution of a solid meal associated with ileal lipid infusion are likely to contribute to the delay in gastric emptying caused by this stimulus.