title: Temporal Characteristics of the Sleep EEG Power Spectrum in Critically Ill Children.
abstract: OBJECTIVE
  Although empirical evidence is limited, critical illness in children is associated with disruption of the normal sleep-wake rhythm. The objective of the current study was to examine the temporal characteristics of the sleep electroencephalogram (EEG) in a sample of children with critical illness.
  
  
  METHODS
  Limited montage EEG recordings were collected for at least 24 hours from 8 critically ill children on mechanical ventilation for respiratory failure in a pediatric intensive care unit (PICU) of a tertiary-care hospital. Each PICU patient was age- and gender-matched to a healthy subject from the community. Power spectral analysis with the fast Fourier transform (FFT) was used to characterize EEG spectral power and categorized into 4 frequency bands: δ (0.8 to 4.0 Hz), θ (4.1 to 8.0 Hz), α (8.1 to 13.0 Hz), and β1/β2 (13.1 to 20.0 Hz).
  
  
  RESULTS
  PICU patients did not manifest the ultradian variability in EEG power spectra including the typical increase in δ-power during the first third of the night that was observed in healthy children. Differences noted included significantly lower mean nighttime δ and θ power in the PICU patients compared to healthy children (p < 0.001). Moreover, in the PICU patients, mean δ and θ power were higher during daytime hours than nighttime hours (p < 0.001).
  
  
  CONCLUSIONS
  The results presented herein challenge the assumption that children experience restorative sleep during critical illness, highlighting the need for interventional studies to determine whether sleep promotion improves outcomes in critically ill children undergoing active neurocognitive development.
authors.affiliation: Anesthesiology and Critical Care Medicine & Pediatrics, Johns Hopkins University School of Medicine, Charlotte R. Bloomberg Children's Center, Baltimore, MD.
authors.forename: Sapna R
authors.initials: SR
authors.lastname: Kudchadkar
authors.affiliation: Anesthesiology and Critical Care Medicine & Pediatrics, Johns Hopkins University School of Medicine, Charlotte R. Bloomberg Children's Center, Baltimore, MD.
authors.forename: Myron
authors.initials: M
authors.lastname: Yaster
authors.affiliation: Department of Medicine, Division of Pulmonary and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, MD.
authors.forename: Arjun N
authors.initials: AN
authors.lastname: Punjabi
authors.affiliation: Division of Sleep and Circadian Disorders, Brigham and Women's Hospital, Division of Sleep Medicine, Harvard Medical School, Boston, MA.
authors.forename: Stuart F
authors.initials: SF
authors.lastname: Quan
authors.affiliation: Arizona Respiratory Center, Colleges of Medicine and Public Health, University of Arizona, Tucson, AZ.
authors.forename: James L
authors.initials: JL
authors.lastname: Goodwin
authors.affiliation: Departments of Anesthesiology and Pediatrics, Division of Pediatric Cardiovascular Anesthesia and Critical Care, Baylor College of Medicine, Texas Children's Hospital, Houston, TX.
authors.forename: R Blaine
authors.initials: RB
authors.lastname: Easley
authors.affiliation: Departments of Medicine and Epidemiology, Johns Hopkins University School of Medicine, Baltimore, MD.
authors.forename: Naresh M
authors.initials: NM
authors.lastname: Punjabi
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D016638:Critical Illness; D004569:Electroencephalography / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D008297:Male; D012121:Respiration, Artificial; D012131:Respiratory Insufficiency / Q000150:complications / Q000628:therapy; D012890:Sleep; D012893:Sleep Wake Disorders / Q000150:complications / Q000175:diagnosis*; D013997:Time Factors
keywords: children; circadian rhythm; critical illness; electroencephalogram; intensive care unit; mechanical ventilation; pediatric critical care; sedation; sleep