Analysis of 24-hour esophageal pH monitoring: the effect of state of consciousness.

This review addresses current advances in the diagnosis of sleep-related gastroesophageal reflux using ambulatory esophageal pH monitoring and laboratory monitoring, which includes polygraphic assessment of the state of consciousness. This 24-hour pH monitoring uses a new strategy of interpretation that characterizes acidic reflux events and specifically assesses the patient's position and state of consciousness. Thus, the recognition of reflux events during waking and sleep will add to the overall assessment of gastroesophageal reflux and its severity and clinical relevance. The pH testing, together with overnight polysomnography, offers an opportunity to link nighttime reflux with disease severity. The application of multichannel impedance with pH monitoring allows detection of acidic and nonacidic reflux events during sleep and also helps to elucidate the physiologic response of the esophagus to these events during sleep. The significance of these findings will increase our knowledge of esophageal physiology and the pathologic mechanisms underlying gastroesophageal reflux disease.