Esophageal manometry can be uncomfortable, but most people can tolerate it. Esophageal manometry is primarily used to diagnose GERD and can be used in cases of regurgitation, heartburn, and sternal pain. The patient is examined by placing a small air bag, which passes through the throat area and is then placed within the esophagus for examination. It is usually left in place for about 24 hours to help monitor the pressure in the test tube and to help diagnose abnormal cardia contractions. Because of the relatively long period of time, many people experience discomfort, especially when sleeping at night. A small number of people may also experience damage to the nasal passages after esophageal manometry. However, these injuries are reversible and do not cause serious sequelae.