title: Cerebral Hemodynamics in Asphyxiated Newborns Undergoing Hypothermia Therapy: Pilot Findings Using a Multiple-Time-Scale Analysis.
abstract: BACKGROUND
  Improved quantitative assessment of cerebral hemodynamics in newborns might enable us to optimize cerebral perfusion. Our objective was to develop an approach to assess cerebral hemodynamics across multiple time scales during the first 72 hours of life in newborns during hypothermia therapy.
  
  
  METHODS
  Spontaneous oscillations in mean arterial pressure and regional cerebral tissue oxygen saturation were analyzed using a moving window correlation method with time scales ranging from 0.15 to 8 hours in this pilot methodology study. Abnormal neurodevelopmental outcome was defined by Bayley III scores and/or cerebral palsy by age 24 months using receiver operating curve.
  
  
  RESULTS
  Multiple-time-scale correlations between the mean arterial pressure and regional cerebral tissue oxygen saturation oscillations were tested in 10 asphyxiated newborns undergoing hypothermia therapy. Large noninduced fluctuations in the blood pressure were observed during cooling in all five infants with abnormal outcomes. Notably, these infants had two distinct patterns of correlation: a positive in-phase correlation at the short time scales (15 minutes) and/or a negative antiphase correlations observed at long time scales (4 hours.). Both the in-phase (area under the curve 0.6, [95% confidence interval 0.2-0.95]) and antiphase correlations (area under the curve 0.75, [95% confidence interval 0.4-0.95]) appeared to be related to an abnormal outcome.
  
  
  CONCLUSIONS
  Our observations suggest that the time scale is an important factor that needs to be standardized in the assessment of neonatal cerebral hemodynamics.
authors: Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, Texas. Electronic address: Lina.chalak@utsouthwestern.edu.
authors: Lina F
authors: LF
authors: Chalak
authors: Department of Bioengineering, University of Texas at Arlington, Dallas, Texas.
authors: Fenghua
authors: F
authors: Tian
authors: Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas; Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital of Dallas, Dallas, Texas.
authors: Takashi
authors: T
authors: Tarumi
authors: Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas; Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital of Dallas, Dallas, Texas.
authors: Rong
authors: R
authors: Zhang
mesh_terms: D062186:Arterial Pressure / Q000502:physiology*; D001238:Asphyxia Neonatorum / Q000503:physiopathology* / Q000628:therapy*; D002560:Cerebrovascular Circulation / Q000502:physiology*; D054022:Cerebrum / Q000378:metabolism*; D005260:Female; D006439:Hemodynamics / Q000502:physiology; D006801:Humans; D007036:Hypothermia, Induced / Q000379:methods*; D007231:Infant, Newborn; D008297:Male; D010101:Oxygen Consumption / Q000502:physiology*; D010865:Pilot Projects; D019265:Spectroscopy, Near-Infrared; D013997:Time Factors; D016896:Treatment Outcome
keywords: cerebral hemodynamics; hypothermia; hypoxic-ischemic encephalopathy (HIE); near infrared spectroscopy (NIRS); neonate