Improved methodology for the Grassi test for intraoperative determination of completeness of vagotomy.

The Grassi test for completeness of vagotomy is a useful adjunct to vagotomy that aids the surgeon in severing all the vagal innervation of the acid-producing portion of the stomach. The Congo Red stick allows the surgeon to perform the Grassi test with a significant reduction in the amount of equipment and personnel required by either pH electrode or liquid Congo Red methods.