Normal Values Of 24-hour Multichannel Intraluminal Impedance In Combination With PH Monitoring For The Detection Of Laryngopharyngeal Reflux And The Study Of Its Affecting Factors

OBJECTIVE: This study used multichannel intraluminal impedance combined with dual-channel p H monitoring to record 24-hour p H-impedance results in asymptomatic volunteers.Impedance monitoring can distinguish between acid reflux,non-acid reflux,liquid reflux,mixed reflux,and gas reflux,as well as the height of the backflow.The distribution of reflux components in the normal population and the monitoring results of the p H and impedance in the throat were analyzed to understand the basic physiological reflux in the asymptomatic population and to analyze whether there were differences between different genders and age groups.METHODS: Through publicity and recruitment,Reflux Symptom Index(RSI)self-evaluation and laryngoscopy were performed in the normal population with no recurrent throat discomfort,no symptoms associated with gastroesophageal reflux.Two experienced physicians performed the reflux finding score(RFS)score.Volunteers with RSI?13 points and RFS?7 points were selected for the study.The subjects underwent high-resolution esophageal manometry to determine the position of the upper esophageal sphincter,and the upper p H channel at a location 1cm above the upper esophageal sphincter.Changes in p H and number of reflux and nature of reflux in the esophagus and pharynx were analyzed,and the differences between gender and age were analyzed.RESULTS: A total of 41 subjects who met the conditions and completed all examination items were included in the study.The p H monitoring results showed that the average p H of the throat in the normal population was 7.0.Impedance results showed that a total of 6,227 reflux events were monitored,957(15%)acid reflux,5,270(85%)non-acid reflux,2155(35%)liquid reflux,and 2276 mixed reflux(36%),gas 1796 times(29%).A total of 824 reflux events were detected in the throat impedance of 41 asymptomatic populations,including 727 uprights(88.2%),97 supine positions(11.8%),2 fluids(0.0%),and 44 mixtures(5%).),gas 778 times(95%).There was a difference between the number of acid reflux in the different gender(P=0.037).There are differences of total number of reflux,number of upright reflux,number of mixed reflux,and number of non-acid reflux in the young and middle-aged groups,with P values of 0.027,0.048,0.036,and 0.027.Conclusion: This study was conducted through a 24-hour multichannel intraluminal impedance combined with PH monitoring of 41 asymptomatic volunteers to establish an initial MII-PH normal range to understand the physiological regurgitation in the normal population.The normal population has an average p H of 7.0 in the throat.Physiological reflux is dominated by non-acid reflux,and gas reflux in the throat.In this study,it was found that the normal number of acid reflux in men was higher than that in women.The total number of reflux,number of upright reflux,number of mixed reflux,and number of nonacid reflux were higher in the young group than in the middle-aged group.In the elderly group,the esophageal motility was weakened,and the bolus clearance time was longer than that of the young group.