Sonographic observations of the gastroduodenal junction in neonatal piglets

Knowledge of the function of the gastroduodenal junction is important, as changes in its motility are associated with gastrointestinal disorders. Sonographic observations were made of the stomach and duodenum of 19 neonatal piglets, 2-6 d of age. Contractions of the stomach and duodenum were identified clearly; the overall rate of gastric contractions was about 4 min-1. The percentage of contractions in which there was a closure of the terminal pyloric antrum and pyloric canal varied, being 57.2% +/- 4.6% in the first postprandial hour and 43.1% +/- 3.0% in the third. Antegrade flow of digesta principally occurred preceding a closure of the pyloric antrum and canal. During contractions of the pyloric antrum, the torus pyloricus moved caudally to fill the lumen of the pyloric canal. Our sonographic method provided a noninvasive technique for studying the form and function of gastroduodenal motility in the neonate, suitable for investigating factors that alter gastric emptying.