The practicality of the Congo Red test, or is your vagotomy complete?

The use of Congo Red testing for adequacy of vagotomy in a variety of clinical situations is described. Its intraoperative use is presented for the first time, thus allowing the surgeon immediate documentation of the completeness of his vagotomy and hopefully averting incomplete vagotomy, the single most common cause of ulcer recurrence after vagotomy-pyloroplasty.