Gastroesophageal reflux and apnea in the preterm infant.

Both apnea and gastroesophageal reflux are nearly universal in premature infants delivered before 32 weeks gestational age. Apnea of prematurity is multifactorial, secondary to immaturity of several different aspects of respiratory control. Amongst these is the laryngeal chemoreflex, when stimulated in newborns results in central and obstructive apnea as opposed to a cough reflex in older infants, an observation leading to a hypothesis that reflux and apnea may be linked. The current evidence for a role of reflux as a causative factor for apnea of prematurity is poor despite multiple studies seeking to prove a relationship. The studies have been hampered by poor design, inadequate measurement techniques and differing endpoints as well as heterogeneous patient populations. Whether subsets of premature infants can be identified in whom GER plays a larger role in disorders of respiratory control will require careful identification of specific patient populations to be studied, accurate measurement of acidic and non-acidic reflux events, and strict definitions of cardiorespiratory endpoints.