The Role of Mean Nocturnal Baseline Impedance and Post reflux Swallow-induced Peristaltic Wave Index in the Diagnosis and Treatment of Gastroesophageal Reflux Disease

Background: As living standards improve, more and more people are becoming overweight or obese, which has led to a gradual increase in the incidence of gastroesophageal reflux disease (GERD). Esophageal multi-channel intraluminal impedance pH monitoring is a technique widely used in the clinical diagnosis of GERD. Commonly used traditional impedance parameters include acid exposure time (AET), number of reflux episodes (NRE), symptom association probability (SAP), and symptom index (SI). Recently, mean nocturnal baseline impedance (MNBI) and post reflux swallow-induced peristaltic wave (PSPW) index have been proposed as novel impedance parameters to evaluate esophageal mucosal integrity and esophageal chemical clearance, respectively. It was also pointed out that MNBI and PSPW index can improve the diagnostic value of impedance pH monitoring and predict the treatment outcome of GERD. Summary: MNBI and PSPW index are objective and reliable novel impedance parameters with high applicability and reproducibility, which are able to improve diagnostic yield of impedance pH monitoring and predict treatment outcomes in GERD patients. Key Messages: In this paper, we mainly review the research progress of the MNBI and the PSPW index in the diagnosis and treatment of GERD.