Insensitivity of ventilatory and arousal mechanisms to hypercarbia and hypoxemia during sleep is a hallmark. Most will present in neonatal period, however in some children presentation is delayed until after infancy. In most affected infants abnormalities during wakefulness will develop in later infancy, with an inadequate response to hypoxemia or hypercarbia and lack of perception of asphyxia. However, this is not progressive and after second or third year they may regain normal awake responses, particularly those who only had abnormal responses during sleep in the neonatal period. Findings are more dramatic during quite sleep than during REM sleep.
Apneas are uncommon.
Good results are usually obtained in children with the mildest forms of the disease, rarely in those with more severe manifestations. Patients who fail to pharmacologic therapy are managed by mechanical ventilation, usually low setting, night-time ventilation through a tracheostomy. In older children different modalities of non-invasive ventilation can be tried. Diaphragmatic pacing has been used successfully for many years and without major complications. However, pacing can be used for up to 12 to 15 hours a day to avoid diaphragmatic fatigue and it has been used mostly for patients with adequate awake responses that require support only at night or for patients who require some support during the daytime but will like freedom from the ventilator for a number of hours during the day.