Impedance-pH monitoring and conventional pH monitoring are complementary methods to detect association between gastroesophageal reflux and apnea-related symptoms in preterm infants and neonates

Objective: To investigate the usefulness of Multichannel intraluminal impedance-pH (MII-pH) monitoring as compared with conventional pH monitoring for detecting Gastroesophageal reflux (GER) episodes and apnea-related symptom association in preterm infants and neonates. Methods: Twenty-three infants (16 preterm and 7 term infants) in hospital, who underwent 24-h MII-pH monitoring, were studied retrospectively. GER indices and apnea-related symptom association were measured by both MII-pH and conventional pH based analysis. Results: Of the total 998 GER episodes assessed by MII-pH monitoring, 407 (40.8%) were acidic and 590 (59.1%) were weakly acidic. A total of 1689 GER episodes were detected by conventional pH based analysis and 270 (16%) were related to retrograde bolus movement. A total of 313 apnea-related symptoms were reported. Five patients had a positive symptom association: 3 by MII-pH, 1 by both MII-pH and conventional pH, 1 only by conventional pH. Conclusions: Addition of MII-pH monitoring to conventional pH monitoring improves the diagnostic yield of symptom association analysis in preterm infants and neonates with apnea-related symptoms. Conventional pH monitoring is still important in the era of impedance measurement.