Apnoea of prematurity

Idiopathic apnoea of prematurity is a common and troublesome disorder which requires therapeutic intervention to avoid potential morbidity in premature infants who require neonatal intensive care. Although the definition of apnoea is inconsistent, this condition has been defined most widely as cessation of breathing in excess of 15 seconds duration, typically accompanied by desaturation and bradycardia. Shorter episodes of apnoea, and even periodic breathing, may be accompanied by bradycardia or hypoxemia, with an incidence approaching 100% in the most immature preterm infants.1 Resolution of apnoea of prematurity runs a very variable time course, and the persistence of such episodes is of uncertain pathophysiologic consequence. Apnoea is traditionally classified into three categories based on the presence or absence of obstruction of the upper airways. Central apnoea is characterised by total cessation of inspiratory efforts with no evidence of obstruction. In obstructed apnoea, the infant tries to breathe against an obstructed upper airway resulting in chest wall motion without airflow throughout the entire apnoea. Mixed apnoea consists of obstructed respiratory efforts usually following central pauses, and is probably the most common type of apnoea.2,3 The site of obstruction in the upper airways is mostly in the pharynx, however, it may also occur at the larynx, and possibly both sites. Mixed apnoea typically accounts for more than half of all long apnoeic episodes, followed in decreasing frequency by