[Analysis of the effect of noninvasive positive-pressure ventilation with simultaneous detection of Dx-pH monitoring in oropharynx and esophagus for 48 hours in patients with moderate and severe OSA].

To investigate the effect of noninvasive positive-pressure ventilation（NPPV） on the related indexes of gastroesophageal reflux（GER） and laryngopharyngeal reflux（LPR） in patients with moderate and severe obstructive sleep apnea（OSA）. This was a retrospective study of 23 cases with moderate or severe OSA and suspected laryngopharyngeal reflux disease （LPRD）. The results of 48h-pH monitoring of oropharynx and esophagus, polysomnography（PSG） and NPPV were analyzed to explore the relationship between reflux related parameters and sleep disordered respiratory. To analyze the impact of NPPV on reflux, the data related to nocturnal reflux with or without NPPV treatment was compared. On the first day of Dx-pH, 5 cases of LPRD were diagnosed with a positive Ryan score rate of 21.7%. There were 19 cases（82.6%） with more than one nocturnal reflux event with pH6.0 as the threshold. Ten cases of GERD were diagnosed with a positive DeMeester score rate of 43.5%. The lowest pH value of oropharynx and esophagus was negatively correlated with the obstructive apnea index（OAI）. The total number of reflux episodes falling below pH thresholds of 6.0 and the duration of the longest episode of gastroesophageal reflux were positively correlated with AHI and OAI（<0.05）. On the night of NPPV treatment, the lowest pH value in the oropharynx increased, while the total number of reflux episodes below pH6.0 and the percentage time below pH5.0 decreased（<0.05）. Similar significant difference was found in the GER parameters（<0.05）. OSA patients were associated with a higher incidence of GER at night and a certain degree of LPR. NPPV treatment can not only effectively improve GER, but also reduce LPR to a certain extent.