title: Relation of sleep state to hypoxemic episodes in ventilated extremely-low-birth-weight infants.
abstract: OBJECTIVE
  To determine whether hypoxemic episodes in ventilated extremely-low-birth-weight infants correlate with specific behavioral states.
  
  
  METHODS
  Three-hour video-electroencephalography-polysomnography was performed on 13 ventilated extremely-low-birth-weight infants with mean postconceptional age of 28.3 weeks. The electroencephalogram was scored for discontinuity. Rapid eye movements, body, head, and limb movements were scored from synchronized video. Sleep states were defined from electroencephalography, rapid eye movements, and movement criteria. Nonparametric statistics were used to test for differences in the proportion of time hypoxemic (oxygen saturation </=85%) between behavioral states.
  
  
  RESULTS
  The proportions of time hypoxemic were 0.6% during quiet sleep, 4.4% during active sleep, 10.7% during indeterminate sleep, and 16.7% during arousal. There was a significant overall difference between the states (P =.004) and a significant difference between active sleep and indeterminate sleep in a pairwise comparison (P =.001).
  
  
  CONCLUSIONS
  Higher proportions of hypoxemia were found during indeterminate sleep and arousal compared with active sleep and quiet sleep. We speculate that motor activity during sleep disruption could prevent effective mechanical delivery of ventilator breaths and contribute to episodes of hypoxemia. Our results suggest that strategies promoting uninterrupted sleep cycling analogous to the intrauterine state could improve ventilatory stability.
authors.affiliation: Department of Pediatrics (Neonatology, Pediatric Neurology), Rainbow Babies and Childrens Hospital, Cleveland, Ohio 44106, USA.
authors.forename: Liisa
authors.initials: L
authors.lastname: Lehtonen
authors.forename: Mark W
authors.initials: MW
authors.lastname: Johnson
authors.forename: Tarif
authors.initials: T
authors.lastname: Bakdash
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Martin
authors.forename: Martha J
authors.initials: MJ
authors.lastname: Miller
authors.forename: Mark S
authors.initials: MS
authors.lastname: Scher
mesh_terms: D005260:Female; D006801:Humans; D000860:Hypoxia / Q000503:physiopathology*; D007231:Infant, Newborn; D019102:Infant, Very Low Birth Weight; D008297:Male; D009820:Ohio; D017286:Polysomnography; D012121:Respiration, Artificial; D012890:Sleep; D012894:Sleep Stages; D018709:Statistics, Nonparametric