title: Tissue oxygenation monitoring during major pediatric surgery using transcutaneous liver near infrared spectroscopy.
abstract: BACKGROUND
  The aim of the study was to compare liver tissue oxygenation determined by near infrared spectroscopy (NIRS) with central venous oxygen saturation (SvO(2)) and intestinal perfusion as measured by gastric intramucosal pH (pHi) in pediatric surgical patients.
  
  
  METHODS
  Twenty children undergoing craniofacial surgery with expected major intraoperative blood loss were studied. NIRS tissue oxygenation index (TOI(Liver)) and pHi values were recorded. Arterial blood gas analysis and SvO(2) were assessed from periodically taken blood samples. Data are presented as ranges (median) and were compared using linear regression analysis. Sensitivity and specificity of the intra-individual changes in TOI(Liver) to predict falling SvO(2) or pHi values were calculated.
  
  
  RESULTS
  Patients age ranged from 0.79 to 8.27 years (1.92 years). TOI(Liver) ranged from 41.5 to 77.4% (61.5%), gastric pHi from 7.13 to 7.60 (7.37) and SvO(2) from 51 to 86% (74%). Among patients only moderate correlation was found between TOI(Liver) and SvO(2) (r = 0.594, P < 0.0001) and gastric pH(i) (r = 0.502, P < 0.0001). Intra-individual measured TOI(Liver) values, however, demonstrated close correlation with SvO(2) values (r = 0.680 to 0.976) but a varying correlation with gastric pHi values (r = 0.055 to 0.972). Sensitivity/specificity of TOI(Liver) to predict decreasing SvO(2) or gastric pHi values were 76.4/73.4% and 67.4/62.7% respectively.
  
  
  CONCLUSIONS
  TOI(Liver) provided a better trend monitor of central venous oxygen saturation than gastric intramucosal pH. Because of its limited sensitivity and specificity to indicate deterioration of SvO(2), liver tissue oxygenation measured by transcutaneous NIRS does not provide additional practical information for clinical management.
authors.affiliation: Department of Anaesthesia, University Children's Hospital, Zurich, Switzerland. markus.weiss@kispi.unizh.ch
authors.forename: Markus
authors.initials: M
authors.lastname: Weiss
authors.forename: Gabriele
authors.initials: G
authors.lastname: Schulz
authors.forename: Ian
authors.initials: I
authors.lastname: Teller
authors.forename: Alexander
authors.initials: A
authors.lastname: Dullenkopf
authors.forename: Anna
authors.initials: A
authors.lastname: Kolarova
authors.forename: Herrmann
authors.initials: H
authors.lastname: Sailer
authors.forename: Claudia M
authors.initials: CM
authors.lastname: Dillier
authors.forename: Hans U
authors.initials: HU
authors.lastname: Bucher
authors.forename: Andreas C
authors.initials: AC
authors.lastname: Gerber
authors.forename: Oskar
authors.initials: O
authors.lastname: Baenziger
mesh_terms: D001784:Blood Gas Analysis / Q000379:methods; D002405:Catheterization, Central Venous / Q000379:methods; D002648:Child; D002675:Child, Preschool; D019465:Craniofacial Abnormalities / Q000601:surgery; D005260:Female; D005753:Gastric Mucosa; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007223:Infant; D016014:Linear Models; D008099:Liver / Q000378:metabolism*; D008297:Male; D008365:Manometry; D016343:Monitoring, Intraoperative / Q000379:methods*; D010100:Oxygen / Q000097:blood / Q000378:metabolism*; D011237:Predictive Value of Tests; D012680:Sensitivity and Specificity; D019265:Spectroscopy, Near-Infrared / Q000379:methods*
chemical_list: D010100:Oxygen