title: Rib cage to abdominal asynchrony in children undergoing polygraphic sleep studies.
abstract: We assessed rib cage (RC) to abdominal (AB) asynchrony in 110 children, aged 1 to 50 months who underwent diagnostic daytime polygraphic sleep studies (PSG), and correlated the results. RC-AB asynchrony was calculated by the phase angle (PA) technique and compared to normal values (0-24 degrees) derived from a separate group of 45 control children, matched for age and weight. Eighty-two of the 110 patients had PSG as part of their evaluation for obstructive sleep apnea. There was a high association between the phase angles and the PSG results (P less than 0.01; Fisher's exact test). PSG was abnormal in 38/82 patients (46%) and the phase angle was increased in 51/82 (62%) (mean +/- SD, 68 degrees +/- 39 degrees; range 28 degrees - 168 degrees) compared to the normal controls (P less than 0.001). Fourteen of the 110 patients had bronchopulmonary dysplasia; of these, PSG and PA results agreed in six normal and seven abnormal studies and disagreed in only one (P = 0.002). Six of 110 patients had Down's syndrome; 5 of 6 had increased RC-AB asynchrony, compared to 3 of 6 who had abnormal PSG. Eight of 110 patients were evaluated for central apnea and hypoventilation; PA was abnormal in 4 of 8, who also had abnormal PSG and in 1 with normal PSG. We conclude that RC-AB measurement by the PA technique may be an important adjunct to the evaluation of breathing disorders during sleep in small children and it may be a good screening test for small children who need PSG.
authors.affiliation: Division of Pediatric Intensive Care, Childrens Hospital Los Angeles, CA 90027.
authors.forename: Y
authors.initials: Y
authors.lastname: Sivan
authors.forename: S D
authors.initials: SD
authors.lastname: Ward
authors.forename: T
authors.initials: T
authors.lastname: Deakers
authors.forename: T G
authors.initials: TG
authors.lastname: Keens
authors.forename: C J
authors.initials: CJ
authors.lastname: Newth
mesh_terms: D000009:Abdominal Muscles / Q000503:physiopathology*; D000402:Airway Obstruction / Q000503:physiopathology*; D001997:Bronchopulmonary Dysplasia / Q000503:physiopathology*; D002675:Child, Preschool; D004314:Down Syndrome / Q000503:physiopathology; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008838:Microcomputers; D008991:Monitoring, Physiologic / Q000295:instrumentation; D012016:Reference Values; D012132:Respiratory Muscles / Q000503:physiopathology*; D012815:Signal Processing, Computer-Assisted / Q000295:instrumentation; D012891:Sleep Apnea Syndromes / Q000503:physiopathology*; D012894:Sleep Stages / Q000502:physiology*; D014939:Work of Breathing / Q000502:physiology*