Respiratory events and sleep structure of children suffering from congenital central hypoventilation syndrome under assisted ventilation: a cross-sectional descriptive study.

Purpose: It has been reported that children with congenital central hypoventilation syndrome (CCHS) are at risk of sleep disturbances. The objectives of our cross-sectional study were to describe nighttime assisted ventilation in children with CCHS, to assess whether children follow the backup rate of home ventilators, whether sleep structure is altered and whether sleep study and PCO₂ monitoring on a systematic basis are useful.

Methods: Children followed up for annual evaluation, including polysomnography under assisted ventilation (pressure-controlled ventilation with a mask or tracheostomy) with transcutaneous PCO₂ recording, were enrolled between 2022 and 2024.

Results: Thirty-eight children (median age [25th; 75th percentiles]: 7.9 years [4.5; 11.1], 18 girls) were enrolled. The observed respiratory rate was significantly lower than the backup rate of the ventilator due to central apneas with upper airway closure under mask ventilation in both NREM and REM sleep during assisted ventilation with mild hypocapnia (nighttime PCO₂: 33.2 mmHg [28.9; 42.1]). A normal sleep structure was found regardless of the CCHS mutations (sleep efficiency: 92% [81; 97]; N3 z-score: -0.58 [-1.35; -0.12]; REM z-score: -0.04 [-1.07; 1.54]) and regardless of the interface used for assisted ventilation (nasal mask, n = 15; facial mask, n = 16; tracheostomy, n = 7). Following the evaluation, changes in assisted ventilation settings were made for 28/38 children (74%; 95% confidence interval: 67-87).

Conclusion: When the assisted ventilation is set to ensure mild hyperventilation due to the backup respiratory rate, a normal sleep structure is found, and assisted ventilation settings are often modified based on transcutaneous PCO₂ measurement.