Clinical Associations of Immature Breathing in Preterm Infants. Part 1: Central Apnea

BACKGROUND: Apnea of prematurity (AOP) is nearly universal among very preterm infants, but neither the apnea burden nor its clinical associations have been systematically studied in a large consecutive cohort. METHODS: We analyzed continuous bedside monitor chest impedance and electrocardiographic waveforms and oxygen saturation data collected on all NICU patients <35 weeks gestation from 2009–2014 (n=1211; >50 infant-years of data). “ABDs”, defined as central apnea ≥10 sec associated with both bradycardia <100 bpm and oxygen desaturation <80%, were identified using a validated automated algorithm. RESULTS: Number and duration of apnea events decreased with increasing gestational age (GA) and post-menstrual age (PMA). ABDs were more frequent in infants <31 wks GA at birth but were not more frequent in those with severe ROP, BPD or severe IVH after accounting for GA. In the day before diagnosis of late-onset septicemia and necrotizing enterocolitis, ABD events were increased in some infants. Many infants continued to experience short ABD events in the week prior to discharge home. CONCLUSIONS: Frequency of apnea events is a function of GA and PMA in infants born preterm, and increased apnea is associated with acute but not with chronic pathologic conditions.