Ambulatory Acid (pH) Probe Tests for Heartburn (Acid Reflux)

These tests use an acid-measuring (pH) probe to identify when, and for how long, stomach acid regurgitates into your esophagus. This information can help your doctor determine how best to treat your condition. In the standard tube test, a nurse or technician sprays your throat with a numbing medication while you're seated. Then a thin, flexible tube (catheter) is threaded through your nose into your esophagus to insert the probe. The probe is positioned just above the lower esophageal sphincter. A second probe may be placed in your upper esophagus. Attached to the other end of the catheter is a small computer that you wear around your waist or with a strap over your shoulder during the test. It records acid measurements. After the probe is in place, you go about your business and then come back one or two days later to have the device removed. A test called a Bravo pH probe may be more comfortable than the standard test, because it eliminates the need for a tube in your nose. In the Bravo test, the probe is attached to the lower portion of your esophagus during endoscopy. The probe transmits a signal to a small computer that you wear around your waist for about two days, and then the probe falls off to be passed in your stool. Another benefit of the Bravo test is that you can shower and sleep more comfortably than with the standard test.