Effects of the Y-U pyloroplasty on gastric emptying and duodenogastric reflux in the dog.

A Y-U pyloroplasty was performed on five healthy adult dogs. Gastric emptying half times (t1/2 GE) of a canned food meal were measured by scintigraphy three times before surgery and three times from 6 to 8 weeks after surgery. Fluoroscopic studies of gastric and duodenal motility were made before surgery and 3, 7, and 35 days after surgery. Clinical observations were made daily throughout the study. Gross and histologic evaluations of the gastroesophageal and pyloric regions were performed at the termination of the study. The t1/2 GE was significantly decreased after surgery. By positive contrast fluoroscopy, the vigor of antral contractions was seen to be decreased in three of the five dogs. On days 7 and 35, fluoroscopic findings were comparable to preoperative studies. Duodenogastric reflux was recognized fluoroscopically in three dogs on four different occasions. This may reflect normal reflux patterns in the dog. No gastrointestinal problems were evident after surgery in four dogs. Reflux esophagitis developed in one dog after surgery, which resolved with therapy. Studies of the Y-U pyloroplasty after 2 months indicated that it decreased gastric emptying time of solid food. Results of postmortem examination showed no abnormal gross or histopathologic changes of esophageal, gastric, or proximal duodenal tissues.