What is it? The Bernstein, or acid perfusion, test involves placing a thin, flexible tube called a catheter through your nose to your esophagus. A saline, or salt, solution, followed by an acid solution is then slowly poured through the catheter. During the test, you'll be asked to report any symptoms the solutions produce.
What is it used for? The Bernstein test helps the doctor determine whether uncommon GERD symptoms, specifically chest pain, are caused by acid or by other factors.
What can I expect? Your doctor will ask you not to eat or drink anything for at least 12 hours before the test and to avoid alcohol for at least 24 hours before the test. Let him or her know if you're taking any medications, since they can affect the results. This test takes about 1 hour. When the catheter is inserted, you may feel slight pain or the need to gag or cough. Also, there may be some pain or discomfort while the solutions are poured through the tube. Afterwards, your throat may be slightly sore.