24-Hour pH Monitoring

24 hour pH testing is typically performed after a manometry study in patients with known or suspected esophageal reflux. A thin tube that detects the level of acidity is passed through the nostril and into the esophagus. The tube is taped to the cheek, brought behind the ear and under the patient's shirt to keep it out of the way. The tube is connected to a monitoring device the size of a small portable cassette player that is worn on the patient's belt. During the test the patient performs all their usual activities including eating, working, gentle exercise and sleeping. The following day, the patient returns for tube removal. The recoding device is then connected to a computer and the data analyzed by the physician.

24-hour pH monitors are placed and subsequently removed at Marin General Hospital by registered nurses who are specialists in gastroenterology procedures.