Characterization of cardiorespiratory events following gastroesophageal reflux in preterm infants

Objective: The aim of this study was to characterize cardiorespiratory events in preterm infants after both acid and nonacid gastroesophageal reflux (GER) as detected by pH and multiple intraluminal impedance (MII). Study Design: Twelve hour overnight studies were performed in 71 preterm infants (gestational age 29.4±3.0 weeks, birth weight 1319±496 g). Apnea ⩾10 s in duration, bradycardia ⩽80 b.p.m. and oxygen desaturation ⩽85% that occurred within 30 s after the initiation of GER were classified as associated with GER. Result: A total of 12 957 cardiorespiratory events and 4164 GER episodes were documented. Less than 3% of all cardiorespiratory events were preceded by GER constituting 3.4% of apnea, 2.8% of oxygen desaturation and 2.9% of bradycardia events. GER did not prolong cardiorespiratory event duration or increase severity. In contrast, GER was associated with a shorter duration of oxygen desaturation events (7.8±4.6 vs 6.3±5.6 s, P