title: Evaluation of change of cerebral circulation by SpO2 in preterm infants with apneic episodes using near infrared spectroscopy.
abstract: BACKGROUND
  In the neonatal intensive care unit (NICU), hemodynamics in very low-birthweight infants are generally examined for oxygen saturation (SpO2), heart rate, respiration rate, and blood pressure. The present study examined how changes in cerebral circulation in preterm infants can be evaluated by the SpO2 monitoring method with near infrared spectroscopy (NIRS) to detect the cerebral circulation.
  
  
  METHODS
  The study was conducted in 11 low-birthweight neonates with a mean weight of 1252 g (940-1948 g), mean post-conceptional age of 28.9 weeks (28-31 weeks) and in whom a total of 145 apneic episodes were examined. Changes in cerebral circulation at the apneic attack were evaluated by two parameters of Delta HbD ( micro mol/L) for reduction in cerebral oxygenation and Delta cHb (mL/100 g brain) for variation in cerebral blood volume using the near infrared spectroscopy (NIRS).
  
  
  RESULTS
  There was a tendency for a reduction in cerebral oxygenation and a change in cerebral blood volume as SpO2 was reduced. In the event of apneic attacks where SpO2 was reduced to <85%, cerebral oxygen saturation was extensively reduced. In addition, cerebral blood volume was also greatly changed when the SpO2 was reduced to <85%, and changed further still when SpO2 was reduced again to < or =75%.
  
  
  CONCLUSIONS
  Reduction in SpO2 (<85%) was suggested to be an effective indication to changes in cerebral circulation. In the case of apneic attacks where SpO2 was < or =85%, the cerebral circulation in preterm low-birthweight neonates was extensively changed and, therefore, attention should be paid to changes in the concentration of SpO2 when managing apnea of prematurity in NICU.
authors.affiliation: Division of Pediatrics, Department of Development and Aging, Faculty of Medicine, Kobe University Graduate School of Medicine, Japan. ayama@med.kobe-u.ac.jp
authors.forename: Akiyo
authors.initials: A
authors.lastname: Yamamoto
authors.forename: Naoki
authors.initials: N
authors.lastname: Yokoyama
authors.forename: Masahiko
authors.initials: M
authors.lastname: Yonetani
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Uetani
authors.forename: Hajime
authors.initials: H
authors.lastname: Nakamura
authors.forename: Hideto
authors.initials: H
authors.lastname: Nakao
mesh_terms: D001049:Apnea / Q000097:blood / Q000503:physiopathology*; D001810:Blood Volume; D002560:Cerebrovascular Circulation; D006801:Humans; D007231:Infant, Newborn; D007235:Infant, Premature, Diseases / Q000097:blood / Q000503:physiopathology*; D019102:Infant, Very Low Birth Weight; D010100:Oxygen / Q000097:blood*; D019265:Spectroscopy, Near-Infrared
chemical_list: D010100:Oxygen