title: Preterm Infants Exhibit Greater Variability in Cerebrovascular Control than Term Infants.
abstract: OBJECTIVE
  Sudden infant death syndrome (SIDS) remains an important cause of infant death, particularly among infants born preterm. Prone sleeping is the major risk factor for SIDS and this has recently been shown to alter cerebrovascular control in term infants. As preterm infants are at greater risk for SIDS than those born at term, we hypothesized that their cerebrovascular control in the prone position would be reduced compared to term infants.
  
  
  METHODS
  There were 35 preterm (mean gestation 31.2 ± 0.4 w) and 17 term (mean gestation 40.1 ± 0.3 w) infants.
  
  
  METHODS
  Infants underwent daytime polysomnography at 2-4 w, 2-3 mo, and 5-6 mo postterm age. Infants slept both prone and supine and were presented with cardiovascular challenges in the form of 15° head-up tilts (HUT).
  
  
  RESULTS
  Cerebral tissue oxygenation index (TOI) was recorded using near-infrared spectroscopy (NIRO-200 spectrophotometer, Hamamatsu Photonics KK, Japan) and mean arterial pressure (MAP) was recorded using a Finometer cuff (Finapres Medical Systems, Amsterdam, The Netherlands). In the prone position TOI increased following the HUT (P < 0.05), whereas no change was seen in the supine position. The overall pattern of response was similar in both groups, but more variable in preterm than term infants (P < 0.05).
  
  
  CONCLUSIONS
  Cerebrovascular control differs between the prone and supine positions in preterm infants. Although overall the responses to head-up tilts were similar between term and preterm infants, greater variability of responses in preterm infants suggests persisting immaturity of their cerebrovascular control in the first year of life, which may contribute to their increased risk of sudden infant death syndrome.
authors: The Ritchie Centre, Hudson Institute of Medical Research and Monash University, Melbourne, Victoria, Australia.|Department of Paediatrics, Monash University, Melbourne, Victoria, Australia.
authors: Karinna L
authors: KL
authors: Fyfe
authors: The Ritchie Centre, Hudson Institute of Medical Research and Monash University, Melbourne, Victoria, Australia.
authors: Alexsandria
authors: A
authors: Odoi
authors: The Ritchie Centre, Hudson Institute of Medical Research and Monash University, Melbourne, Victoria, Australia.|Department of Paediatrics, Monash University, Melbourne, Victoria, Australia.
authors: Stephanie R
authors: SR
authors: Yiallourou
authors: The Ritchie Centre, Hudson Institute of Medical Research and Monash University, Melbourne, Victoria, Australia.|Department of Paediatrics, Monash University, Melbourne, Victoria, Australia.|Monash Newborn, Monash Medical Centre, Melbourne, Victoria, Australia.
authors: Flora Y
authors: FY
authors: Wong
authors: The Ritchie Centre, Hudson Institute of Medical Research and Monash University, Melbourne, Victoria, Australia.
authors: Adrian M
authors: AM
authors: Walker
authors: The Ritchie Centre, Hudson Institute of Medical Research and Monash University, Melbourne, Victoria, Australia.|Department of Paediatrics, Monash University, Melbourne, Victoria, Australia.
authors: Rosemary S C
authors: RS
authors: Horne
mesh_terms: D002561:Cerebrovascular Disorders / Q000150:complications* / Q000503:physiopathology*; D005260:Female; D018475:Head-Down Tilt; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007234:Infant, Premature / Q000502:physiology*; D008297:Male; D017286:Polysomnography; D016684:Prone Position; D012307:Risk Factors; D012890:Sleep / Q000502:physiology; D013398:Sudden Infant Death / Q000209:etiology*; D016683:Supine Position
keywords: blood pressure; cerebral blood flow; cerebral oxygenation; cerebrovascular circulation; preterm birth