Multichannel intraluminal impedance to study gastroesophageal reflux in mechanically ventilated children in the first 48 h after PICU admission

ObjectiveThe aim of this study was to determine the incidence, characteristics, related factors, and clinical implications of gastroesophageal reflux (GER) in critically ill children using esophageal pH monitoring and multichannel intraluminal impedance.MethodsA prospective observational clinical study was performed including 36 non-enterally fed critically ill children with mechanical ventilation, aged 1 mo to 7 y, in the first 48 h after admission in the pediatric intensive care unit (PICU). Esophageal pH monitoring and multichannel intraluminal impedance were used.ResultsMultichannel intraluminal impedance detected 352 episodes of GER (20.1% acid, 53.8% weak acid, 26% alkaline), whereas pH monitoring detected 171 episodes (100% acid). There were no differences in the type of reflux according to age and no differences in the number or type of reflux according to the administration of inotropic or sedatives drugs or the duration of mechanical ventilation. Patients treated with vecuronium had fewer episodes of GER than those without muscle relaxant drugs.ConclusionsThe incidence of GER in non-enterally fed critically ill children with mechanical ventilation is high in the first 48 h after admission to the PICU. Multichannel intraluminal impedance is more sensitive than pH monitoring for establishing the diagnosis of GER because the refluxate is alkaline or weak acid in the majority of episodes. Patients who received muscle relaxants had a lower frequency of GER.