pH Impedance Testing

pH Impedance testing is a sophisticated diagnostic tool used to evaluate the frequency and nature of gastrointestinal reflux. While traditional pH tests only measure acid levels, impedance testing allows doctors to detect both acidic and non-acidic reflux (such as bile or stomach enzymes). This is particularly useful for patients who continue to experience symptoms like coughing, throat clearing, or heartburn even while taking acid-suppressing medications. By measuring the electrical resistance (impedance) within the esophagus, the test can determine if liquid, gas, or a mixture of both is moving upward from the stomach.

The procedure involves a thin, flexible catheter inserted through the nose and positioned in the esophagus for 24 hours. The catheter is connected to a small recording device worn on a belt. During the testing period, the patient goes about their normal activities, eats their regular diet, and logs their symptoms, meals, and sleep times. This allows physicians to correlate symptoms directly with reflux events. It provides a definitive answer as to whether a patient’s discomfort is truly caused by reflux or if it stems from a different issue, such as esophageal hypersensitivity, guiding more effective treatment choices.