The relationship between apnea, bradycardia, and feeding intolerance is extremely controversial and requires additional investigation.[26] Gastroesophageal reflux occurs when the gastric contents enter into the esophagus due to a relaxed esophageal sphincter and is a common phenomenon in preterm infants. It is hypothesized that apnea events caused by GER are obstructive in nature and are caused by mechanisms that lead to the closure of the glottis. However, recent studies have shown that there is no significant relationship between GER and the occurrence of apnea and bradycardia episodes after a GER event.
There are multiple differential diagnoses associated with apnea; however, there is an association between increased respiratory support and NEC.[28] Apnea and bradycardia episodes are considered common in preterm infants and may be discounted until they are severe in number or intensity. Cardiovascular and hemodynamic deterioration can occur quickly in the preterm infant and should be monitored closely, especially if occurring with other symptoms of feeding intolerance.