title: Evaluation of cerebral oxygenation during procedural sedation in children using near infrared spectroscopy.
abstract: OBJECTIVE
  We evaluate the utility of near infrared spectroscopy monitoring and its correlation to conventional respiratory monitors during changes in cardiorespiratory characteristics during pediatric procedural sedation.
  
  
  METHODS
  In this prospective observational study of 100 children, cerebral oxygenation (rSO(2)), pulse oximetry (SpO(2)), and end-tidal carbon dioxide (etco(2)) were monitored continuously. Values were manually recorded at least every 3 minutes from baseline until 30 minutes after sedative administration, resulting in 1,515 triplicate (simultaneous near infrared spectroscopy/etco(2)/SpO(2)) measurements. Correlations between conventional monitoring characteristics (SpO(2) and etco(2)) and rSO(2) were determined, with focus during adverse cardiorespiratory events.
  
  
  RESULTS
  Cerebral oxygenation remained normal in 1,483 of 1,515 measurements (97.9%). rSO(2) decreased significantly during 3 of 13 hypoxic events occurring in 13 patients and during 5 of 17 hypercarbic events occurring in 8 patients, with 15 measurements of greater than 20% decrease from baseline. Cerebral oxygenation increased transiently in 88% of children. During 31 cerebral desaturation recordings, 3 hypoxic recordings (9.3%, always in combination with hypercarbia) and 5 hypercarbic recordings (15.6%) were observed, whereas in 23 (74.2%), cardiorespiratory characteristics were unchanged. There was poor correlation between rSO(2) and both SpO(2) and etco(2), with correlation coefficients of 0.05 (95% confidence interval 0.04 to 0.07) and 0.01 (95% confidence interval -0.01 to 0.02), respectively.
  
  
  CONCLUSIONS
  Cerebral oxygenation as measured by near infrared spectroscopy demonstrated few significant negative changes during pediatric procedural sedation. Transient cardiorespiratory events seldom altered rSO(2), with hypercarbia having a greater effect than hypoxemia. However, cerebral desaturations frequently occurred without associated cardiorespiratory changes.
authors.affiliation: Department of Pediatrics, Division of Pediatric Emergency Medicine, University of Louisville, Louisville, KY, USA. p0padm01@gwise.louisville.edu
authors.forename: Pradeep
authors.initials: P
authors.lastname: Padmanabhan
authors.forename: John W
authors.initials: JW
authors.lastname: Berkenbosch
authors.forename: Doug
authors.initials: D
authors.lastname: Lorenz
authors.forename: Mary Clyde
authors.initials: MC
authors.lastname: Pierce
mesh_terms: D000293:Adolescent; D001923:Brain Chemistry; D002560:Cerebrovascular Circulation; D002648:Child; D002675:Child, Preschool; D016292:Procedural Sedation / Q000009:adverse effects; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D019370:Observation; D010092:Oximetry; D010100:Oxygen / Q000032:analysis*; D011446:Prospective Studies; D012039:Regional Blood Flow; D019265:Spectroscopy, Near-Infrared / Q000379:methods*; D018709:Statistics, Nonparametric
chemical_list: D010100:Oxygen