title: Inhibitory Effect of Nasal Intermittent Positive Pressure Ventilation on Gastroesophageal Reflux.
abstract: Non-invasive intermittent positive pressure ventilation can lead to esophageal insufflations and in turn to gastric distension. The fact that the latter induces transient relaxation of the lower esophageal sphincter implies that it may increase gastroesophageal refluxes. We previously reported that nasal Pressure Support Ventilation (nPSV), contrary to nasal Neurally-Adjusted Ventilatory Assist (nNAVA), triggers active inspiratory laryngeal closure. This suggests that esophageal insufflations are more frequent in nPSV than in nNAVA. The objectives of the present study were to test the hypotheses that: i) gastroesophageal refluxes are increased during nPSV compared to both control condition and nNAVA; ii) esophageal insufflations occur more frequently during nPSV than nNAVA. Polysomnographic recordings and esophageal multichannel intraluminal impedance pHmetry were performed in nine chronically instrumented newborn lambs to study gastroesophageal refluxes, esophageal insufflations, states of alertness, laryngeal closure and respiration. Recordings were repeated without sedation in control condition, nPSV (15/4 cmH2O) and nNAVA (~ 15/4 cmH2O). The number of gastroesophageal refluxes recorded over six hours, expressed as median (interquartile range), decreased during both nPSV (1 (0, 3)) and nNAVA [1 (0, 3)] compared to control condition (5 (3, 10)), (p < 0.05). Meanwhile, the esophageal insufflation index did not differ between nPSV (40 (11, 61) h-1) and nNAVA (10 (9, 56) h-1) (p = 0.8). In conclusion, nPSV and nNAVA similarly inhibit gastroesophageal refluxes in healthy newborn lambs at pressures that do not lead to gastric distension. In addition, the occurrence of esophageal insufflations is not significantly different between nPSV and nNAVA. The strong inhibitory effect of nIPPV on gastroesophageal refluxes appears identical to that reported with nasal continuous positive airway pressure.
authors.affiliation: Neonatal Respiratory Research Unit, Department of Pediatrics, Université de Sherbrooke, Sherbrooke, Quebec, Canada.|Department of Physiology, Université de Sherbrooke, Sherbrooke, Quebec, Canada.
authors.forename: Danny
authors.initials: D
authors.lastname: Cantin
authors.affiliation: Neonatal Respiratory Research Unit, Department of Pediatrics, Université de Sherbrooke, Sherbrooke, Quebec, Canada.|Department of Pediatrics, Université Picardie Jules Verne, Amiens, France.
authors.forename: Djamal
authors.initials: D
authors.lastname: Djeddi
authors.affiliation: Neonatal Respiratory Research Unit, Department of Pediatrics, Université de Sherbrooke, Sherbrooke, Quebec, Canada.|Department of Physiology, Université de Sherbrooke, Sherbrooke, Quebec, Canada.
authors.forename: Vincent
authors.initials: V
authors.lastname: Carrière
authors.affiliation: Neonatal Respiratory Research Unit, Department of Pediatrics, Université de Sherbrooke, Sherbrooke, Quebec, Canada.|Department of Physiology, Université de Sherbrooke, Sherbrooke, Quebec, Canada.
authors.forename: Nathalie
authors.initials: N
authors.lastname: Samson
authors.affiliation: Neonatal Respiratory Research Unit, Department of Pediatrics, Université de Sherbrooke, Sherbrooke, Quebec, Canada.|Department of Physiology, Université de Sherbrooke, Sherbrooke, Quebec, Canada.
authors.forename: Stéphanie
authors.initials: S
authors.lastname: Nault
authors.affiliation: Neonatal Respiratory Research Unit, Department of Pediatrics, Université de Sherbrooke, Sherbrooke, Quebec, Canada.|Department of Physiology, Université de Sherbrooke, Sherbrooke, Quebec, Canada.
authors.forename: Wan Lu
authors.initials: WL
authors.lastname: Jia
authors.affiliation: Department of Pediatrics, University of Toronto, Toronto, Ontario, Canada.|Keenan Research Centre for Biomedical Science of St. Michael's Hospital, Toronto, Ontario, Canada.|Institute for Biomedical Engineering and Science Technology (iBEST) at Ryerson University and St-Michael's Hospital, Toronto, Ontario, Canada.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Beck
authors.affiliation: Neonatal Respiratory Research Unit, Department of Pediatrics, Université de Sherbrooke, Sherbrooke, Quebec, Canada.|Department of Physiology, Université de Sherbrooke, Sherbrooke, Quebec, Canada.
authors.forename: Jean-Paul
authors.initials: JP
authors.lastname: Praud
mesh_terms: D000818:Animals; D045422:Continuous Positive Airway Pressure / Q000009:adverse effects / Q000379:methods*; D005764:Gastroesophageal Reflux / Q000628:therapy*; D012119:Respiration; D012756:Sheep