of prematurity is diagnosed based on clinical grounds in premature neonates
after systemic and pulmonary causes of apnea have been excluded. Auditory
brainstem evoked responses are delayed in a large number of premature
neonates with apnea. A brainstem conduction showing a III to V interpeak
latency below 5.6 milliseconds usually coincides with resolution of apnea
of apnea of prematurity includes stimulation, pharmacologic intervention
(caffeine or theophylline), continuous positive airway pressure, and mechanical
ventilation. The usual loading dose of caffeine citrate is 20 mg/kg followed
by a maintenance dose of 5 mg/kg per day beginning 24 hours after the
loading dose. The usual loading dose of theophylline is 5 mg/kg followed
by 1.5 to 2 mg/kg every 8 hours.
Congenital hypoventilation syndrome
produces hypoxemia, especially during quiet sleep, even in the absence
of apnea. Apnea is central and occurs predominantly during quiet sleep.
Congenital central hypoventilation syndrome is a diagnosis of exclusion.
Congenital hypoventilation syndrome may be associated with Hirshprung
disease and Rett syndrome.
. The diagnosis is supported by the presence of
sustained hypoxia during quiet sleep.
Central hypoventilation syndrome may improve with doxapram but tracheostomy
with mechanical ventilation or a diaphragmatic pacemaker are usually required.
Apnea in startle disease (hyperekplexia)
occurs during spontaneous or provoked episodes of generalized stiffening.
Episodes of stiffening may be provoked by noise or touch. Tapping the
nose is particularly likely to produce an apneic episode in neonates with
startle disease. Apnea in neonates with startle disease stops with forced
flexion of the neck and legs towards the trunk.
Feeding apnea is diagnosed clinically.
Feeding apnea may be central, obstructive, or mixed. It occurs during
feeding in preterm and term neonates and is controlled by frequent interruption
during feeding. Feeding apnea is probably due to lack of coordination
between breathing and swallowing mechanisms in the brainstem.