SLEEP-DISORDERED BREATHING IN CHILDREN WITH MYELOMENINGOCELE

Background: Although patients with myelomeningocele and the Chiari II malformation are known to have sleep apnea and respiratory control def icits, the prevalence, types, severities, and associations of sleep-di sordered breathing (SDB) have not been adequately defined. Methods: A cross-sectional study of our myelomeningocele clinic population was un dertaken to correlate polysomnographic results with historical data an d findings from magnetic resonance imaging of the Chiari malformation, pulmonary function results, and nocturnal pulse oximetry. Results: A questionnaire survey of symptoms was available for 107 of 109 children (98% of the clinic population), and 85 patients agreed to undergo ove rnight polysomnography. Breathing during sleep was classified as norma l in 31 cases (37%), mildly abnormal in 35 cases (42%), and moderately /severely abnormal in 17 cases (20%). Among the 17 patients with moder ately/severely abnormal SDB, 12 patients had predominantly central apn eas and 5 had predominantly obstructive apnea. Patients with a thoraci c or thoracolumbar myelomeningocele, those who had previously had a po sterior fossa decompression operation, those with more severe brain-st em malformations, and those with pulmonary function abnormalities were more likely, to have moderately/severely abnormal SDB, relative risks (95% confidence intervals) 9.2 (2.9 to 29.3), 3.5 (1.3 to 8.9), 3.0 ( 0.9 to 10.5), and 11.6 (1.6 to 81.3), respectively, Failure of obstruc tive SDB to resolve after adenotonsillectomy in four patients suggeste d abnormal control of pharyngeal airway patency during sleep. Nocturna l pulse oximetry accurately predicted moderately/severely abnormal SDB with a sensitivity of 100% and a specificity of 67%. Conclusions: The pathogenesis of SDB in patients with myelomeningocele involves the fu nctional level of the spinal lesions, congenital and acquired brain-st em abnormalities, pulmonary function abnormalities, disorders of upper airway maintenance, and sleep state. Polysomnography and nocturnal pu lse oximetry should be performed in high-risk patients to detect and c lassify SDB.