Although most children with esophageal atresia (EA) off medication have a normal reflux index, they still experience a significant number of nonacid retrograde bolus movements (RBM), which automated software can over-detect in this population, according to a study published in the Journal of Pediatric Gastroenterology and Nutrition.
Many patients with EA suffer from chronic gastroesophageal reflux (GERD), but only a few experience troublesome symptoms such as regurgitation, vomiting, and heartburn. Although current guidelines recommend reflux monitoring in pediatric EA patients beginning at 1 year of age and during long-term follow-up in symptomatic children, there are no reference values for pediatric pH-impedance (pH-MII) monitoring.
The current study was designed to assess acid and nonacid GERD using pH-MII monitoring, in infants and school-age children with EA using pH-MII monitoring (N=57; 24 infants and 33 school-age children [median 8.2 years]). Data were taken from the retrospective review of patient records at a Dutch hospital where all children born with EA are offered a 24-hour pH-MII study at 18 months and again at 7 to 9 years as part of a longitudinal multidisciplinary follow-up program. All antacid and prokinetic therapies were discontinued before the studies. Exclusion criteria included tube feeding, esophageal replacement therapy, isolated tracheoesophageal ﬁstula, and monitoring less than 18 hours.
A manual review was performed for all automatically detected RBM that were confirmed by the Medical Measurement Systems (MMS) software according to acid/alkaline limits (pH 4.0 and 7.0), minimum reflux duration pH- and MII-results (5 seconds), and air threshold (5000 V). All reflux events identified by the software were modified (duration; liquid/mixed reflux content; number of impedance channels involved) by one researcher unaware of the participants’ clinical symptoms and by another who examined inconclusive events. If both reviewers agreed that the software misinterpreted an RBM, it was deleted.
A total of 3313 RBM were detected by the MMS software, of which 39% (n=1287) were manually deleted from the tracings, most frequently for swallows that were misinterpreted as RBM (52% of the total nonacid RBM detections and 8% of the total acid RBM detections). The median reflux index in infants was 2.6% compared with 0.6% in school-age children. Among the infant participants, 10% (2/22) of pH results were abnormal, 64% (14/22) were normal, and 27% (6/22) were indeterminate. The median incidence of RBM in infants was 61 (range 0-134). Among school-age participants, 12.5% (4/32) of pH results were abnormal, 81% (26/32) were normal, and 6% (2/32) were indeterminate. The median RBM in older children was 21 (range 0-54).
The study investigators concluded that “most infants and school-aged children with EA off medication have a normal [reflux index], yet experience a significant number of nonacid RBM. After manual revision of the tracings, a high percentage of RBM was deleted. These were mainly nonacid swallows, which the software incorrectly identified as RBM. Our data show that automated impedance analysis software needs refinement for use in infants and children with EA and question the need for standard antiacid therapy in these patients.”
Vergouwe FWT, van Wijk MP, Spaander MCW, et al. Evaluation of gastroesophageal reflux in children born with esophageal atresia using pH and impedance monitoring. J Pediatr Gastroenterol Nutr. 2019;69(5):515-522