Gastric emptying of liquids after different vagotomies and pyloroplasty.

Gastric emptying of five liquid meals which differ in their physicochemical properties have been measured in control dogs and dogs that have received a Heinecke-Mikulicz pyloroplasty alone, proximal gastric vagotomy without drainage, selective gastric vagotomy and pyloroplasty and truncal vagotomy and pyloroplasty. The first two phases of emptying have been computed by the method of least squares to obtain a logarithmic-linear pattern and are expressed as relative rates: The initial post-ingestion process is characterized by beta or the average relative rate of emptying in the first ten minutes, the basic or exponential rate as beta and the change in rate from the initial to basic pattern as deltabeta. Each measure of gastric emptying was statistically analyzed to determine specific differences in rates between the operations studied. We confirmed the earlier claims that pyloroplasty alone does not change the emptying rate of liquid meals. Each measure or phase of emptying varies consistently across the operations from meal to meal tested. Initial emptying after all three vagotomies is significantly faster than control with progressive rate increases as proximal gastric vagotomy is compared with selective gastric vagotomy with pyloroplasty and with truncal vagotomy with pyloroplasty, probably indicative of gastric fundal loss of accommodation to volume distention after denervation. The basic exponential pattern of emptying is not lost after any of the operations studied. The basic rate after proximal gastric vagotomy and selective gastric vagotomy with pyloroplasty is nearly identical, slightly delayed from the control rate and significantly slower than the more rapid rate after truncal vagotomy with pyloroplasty. Possible explanations for these are discussed and imply a particular importance of the hepatic and celiac vagal fibers, sectioned only with truncal vagotomy, in the regulation of gastric emptying of liquids.