Association of apnea and nonacid gastroesophageal reflux in infants: Investigations with the intraluminal impedance technique

An association of apnea and gastroesophageal reflux (GER) was proposed prev iously. However, pH metry as the standard diagnostic tool for GER only meas ures acid reflux (pH < 4). it is difficult to interpret studies in infants with a presumed association between apnea and GER based on pH metry because the buffering effect of feeding may result in predominantly nonacid GER. T he aim of this study was to investigate the temporal association of apnea a nd GER with the pH-independent intraluminal impedance technique (IMP). Infa nts with recurrent regurgitation or respiratory symptoms suggestive of apne a were investigated simultaneously with IMP, pH monitoring, and polygraphy. IMP patterns, pH, oronasal flow, and chest wall movement were recorded and analyzed. In 22 infants, 364 GER episodes were recorded by IMP. One hundred and sixty -five apneas were documented by visual validation of polygraph records. For ty-nine apneas (29.7%) were associated with GER; 11 (22.4%) of these showed acid reflux (pH < 4). A significant correlation between the time spent apn eic and GER was found (P < 0.001). There is marked association between apnea and gastroesophageal reflux in in fants. Patients potentially at risk cannot be reliably identified by pH met ry. Its exclusive use is therefore not suitable for the detection of all GE R-associated apneas in infants. The pH-independent intraluminal impedance t echnique has proven to be a sensitive diagnostic tool for this approach, Pe diatr Pulmonol, 2001; 31:144-149. (C) 2001 Wiley-Liss, Inc.