3 tests are used to measure reflux of material, particularly acid, from your stomach into your esophagus:
What is the 48-hour esophageal pH monitoring test?
An esophageal pH test measures how often and for how long stomach acid enters the esophagus (tube from mouth to stomach). The test is used to determine if you have gastroesophageal reflux disease (GERD), which is when stomach contents (particularly acid) backs up into your esophagus. A thin tube with a monitor is inserted through your nose or mouth into your stomach. You will wear this monitor on a strap for two days to track the acidity level, and you will be asked to write down symptoms you experience over that 48-hour period. These will be matched with reflux events detected by the monitor.
What is the Bravo pH test?
This test also measures acid reflux into the esophagus but instead of a tube placed through your nose into the stomach a small sensor is clipped to your esophagus under sedation using endoscopy and measures acidity in a wireless fashion for 48 hours. You will also be asked to keep a diary of your symptoms.
What is the Impedance pH test?
Some reflux is not due to acid and this test, which also involves placing a small catheter through your nose into the esophagus, measures this unusual type of reflux.
Which test is right for me and how do I prepare for it?
Based on your symptoms your gastroenterologist will decide which test will provide the answers he/she needs to decide what treatment you should receive for your reflux symptoms. To prepare for the test you will be asked to avoid eating, drinking or smoking after midnight before the test. It is very important to alert your physician if you have a pacemaker or heart defibrillator or a history of bleeding problems or if you are on blood thinners. Because certain drugs may affect test results, you may be asked to stop taking some medications such as acid suppressants, certain blood pressure medications, alcohol, antacids and corticosteroids.