Nocturnal oxygen saturation in children with stable cystic fibrosis.

BACKGROUND: Hypoxemia during sleep is a common finding in Cystic Fibrosis (CF) patients with more advanced lung disease. Nocturnal hypoxemia is associated with frequent awakenings and poor sleep quality. For children with CF, data of nocturnal oxygen saturation are sparse.
OBJECTIVE: To assess the oxygen saturation profile during sleep in 25 clinically stable children with CF lung disease and to correlate these data with spirometry, cough frequency, sleep quality, and CT-scan scores.
METHOD: During two nights cough was recorded with a digital audio recorder in 25 clinically stable CF patients. In addition oxygen saturation was measured. The day following the recording spirometry was carried out. CT scores were obtained from the most recent routine CT scan.
RESULTS: Twenty-two patients were included in the study. Mean age (range) was 13 (6-18) years. Spirometry was FVC% 84 (range 52-114), FEV(1) % 77 (range 43-115), and FEF(75) % 50 (range 12-112). The mean SO(2) was 95.6% for the first and 96.2% for the second night. Mean SO(2) between the two nights correlated strongly (r(s) = 0.84, P < 0.001). Positive correlation was observed between mean SO(2) of the two nights (mean × SO(2)) and FVC, FEV(1) and FEF(75). Correlations were found between mean × SO(2) and the total CT score (r(s) = -0.45, P = 0.05) and the bronchiectasis subscore (r(s) = -0.48, P = 0.03).
CONCLUSION: Nocturnal oxygen saturation in children with stable CF is lower than that in healthy children, and is correlated with lung function parameters and CT scores. Monitoring oxygen saturation during one night is sufficient to get a representative recording.