Gastric Secretion and Motility After Vagotomy in Dogs

Abstract

To study the changes in gastric secretion and motility after vagotomy, seven dogs were observed before and at intervals to one year after this operation. Methods: After thorough training and preoperative tests, seven mongrel dogs weighing from ten to eighteen pounds were sUbjected to transthoracic vagotomy. Three to five centimeters of the vagi were removed just above the diaphragm. One, three, six, nine and twelve months later tests were repeated. All studies were performed after a twenty-four hour fast. Gastric amilysis was performed after 1.0 mgm of histamine subcutaneously, after 2.0 mgm of urecholine subcutaneously and after 20 U of insulin intravenously. Titration was with 0.1 normal sodium hydroxide using Topfer's reagent and phenolphthalein as indicators. Gastric motility was recorded on a kymograph by a bromoform manometer connected to a Levine tube on the end of which was a rubber balloon. The 12tter was passed into the stomach and inflated with 250 cubic centimeters of air. Resting gastric motility and response to 2.0 mgm of urecholine subcutaneously and to 20 U of insulin intravenously were recorded. Emptying time was observed fluoroscopically after passage of 50 cubic centimeters of barium and water mixture into the stomach through a Levine tube. Results: The changes in free and total acid secretion are shown in figures 1, 2 and 3, and in the emptying time in table 1. By the method employed, the changes in intragastric pressure representing motility preoperatively showed waves from one to four centimeters of bromoform in height occurring at the rate of three to six per minute. After vagotomy, very small irregular waves were noted in most records, occasionally reaching the height of the preoperative test waves but infrequently attaining the same rate. In only nine of a total of sixty-three records were no waves seen. A few records showed large 8 to 20 centimeter waves, spaced at intervals of several minutes. Before and after operation, urecholine caused prompt increase in height and frequency of waves, with rapid increase in tone (height of lowest point of waves from base line). The maximum response was reached in from five to eight minutes. Occasionally the test was terminated at this point by the dog retching with breaking or expulsion of the balloon.