title: Measurement of cerebral oxygenation state in anaesthetized children using the INVOS 5100 cerebral oximeter.
abstract: BACKGROUND
  Near-infrared spectroscopy is a developing technique for monitoring cerebral oxygenation during anaesthesia. The aim of this study was to evaluate absolute values of cerebral oxygenation during stable anaesthesia conditions in otherwise healthy children using the recently introduced INVOS 5100 cerebral oximeter with a paediatric and adult sensor and to compare them with values obtained from the NIRO 300 oximeter.
  
  
  METHODS
  Thirty paediatric surgical patients (aged 0.23-15.97 years) were studied during general anaesthesia with tracheal intubation and controlled ventilation. Comparative measurements of cerebral oxygenation were performed on the forehead with two probes within 10 min under stable cardiorespiratory and anaesthesia conditions. Cerebral oxygenation values (rSO2) obtained from the paediatric and adult INVOS 5100 sensors were compared with the tissue oxygenation index (TOI) obtained from the NIRO 300 cerebral oximeter using 4- and 5-cm emitter-detector separation.
  
  
  RESULTS
  Cerebral rSO2 values and the TOI values both showed a large range of cerebral oxygenation in the children studied (rSO2: 59-95%, TOI: 48-85%). Cerebral rSO2 values measured by the INVOS 5100, particularly with the paediatric sensor, were significantly higher than the TOI values obtained from the NIRO 300 (P < 0.0001). Agreement between the INVOS and NIRO oximeter was poor.
  
  
  CONCLUSIONS
  The large range and the poor agreement of cerebral oxygenation values between the two oximeters makes it difficult to define a normal value. Cerebral oxygenation readings by these monitors, based on one single point measurement during anaesthesia, should be viewed with caution. Actually, there may be little indication for routine use of such monitoring during general anaesthesia.
authors.affiliation: Departments of Anaesthesia and Intensive Care and Neonatology, University Children's Hospital Zurich, Steinwiesstrasse 75, CH-8032 Zurich. markus.weiss@kispi.unizh.ch
authors.forename: Alexander
authors.initials: A
authors.lastname: Dullenkopf
authors.forename: Bernhard
authors.initials: B
authors.lastname: Frey
authors.forename: Oskar
authors.initials: O
authors.lastname: Baenziger
authors.forename: Andreas
authors.initials: A
authors.lastname: Gerber
authors.forename: Markus
authors.initials: M
authors.lastname: Weiss
mesh_terms: D000293:Adolescent; D000758:Anesthesia; D001835:Body Weight / Q000502:physiology; D001923:Brain Chemistry / Q000502:physiology*; D002648:Child; D002675:Child, Preschool; D005260:Female; D006439:Hemodynamics; D006801:Humans; D007223:Infant; D008297:Male; D016343:Monitoring, Intraoperative; D010092:Oximetry / Q000295:instrumentation*; D010100:Oxygen / Q000097:blood; D010101:Oxygen Consumption / Q000502:physiology; D015203:Reproducibility of Results
chemical_list: D010100:Oxygen