title: Reliability of the NeuroTrend sensor system under hyperbaric conditions.
abstract: OBJECTIVE
  The goal of this study was to investigate the reliability of the multi-parameter sensor NeuroTrend in a hyperbaric environment for up to 3bar absolute pressure. Measurement of brain tissue oxygenation (ptiO2) under hyperbaric conditions is supposed to elucidate whether hyperbaric oxygenation therapy has the potential to improve ptiO2 to a clinically significant degree in pathological altered brain tissue after traumatic brain injury.
  
  
  METHODS
  The NeuroTrend sensor hose, filled with equilibrated plasma samples, was stored in a decompression chamber. The plasma samples were equilibrated with three different gas mixtures. After determination of the initial values for temperature, oxygen partial pressure (pO2), carbon dioxide partial pressure (pCO2) and hydrogen ion concentration (pH) in the plasma, the ambient pressure was stepwise increased from 0.1 to 3 bar. The same set-up was performed without increasing the ambient pressure.
  
  
  RESULTS
  No significant difference in the mean values for all 23 measurement points and for all parameters (pO2, pCO2, pH) of all 10 NeuroTrend sensors was found, under both normobaric and hyperbaric conditions.
  
  
  CONCLUSIONS
  The study demonstrated that an absolute ambient pressure up to 3 bar did not influence the measuring properties and the reliability of the NeuroTrend sensor.
authors.affiliation: Department of Anesthesiology and Intensive Care Medicine, Martin-Luther-University Halle, Wittenberg, Dryander Street 4-7, Halle (Saale) 06097, Germany. dirk.henze@medizin.uni-halle.de
authors.forename: Dirk
authors.initials: D
authors.lastname: Henze
authors.forename: Michael
authors.initials: M
authors.lastname: Bomplitz
authors.forename: Joachim
authors.initials: J
authors.lastname: Radke
authors.forename: Tobias
authors.initials: T
authors.lastname: Clausen
mesh_terms: D015374:Biosensing Techniques / Q000379:methods*; D001921:Brain / Q000098:blood supply / Q000378:metabolism*; D002245:Carbon Dioxide; D004566:Electrodes; D006801:Humans; D006863:Hydrogen-Ion Concentration; D006931:Hyperbaric Oxygenation; D008365:Manometry / Q000379:methods; D008991:Monitoring, Physiologic / Q000379:methods*; D009584:Nitrogen; D010100:Oxygen / Q000378:metabolism; D010313:Partial Pressure; D010949:Plasma / Q000378:metabolism; D011897:Random Allocation; D015203:Reproducibility of Results; D013696:Temperature
chemical_list: D002245:Carbon Dioxide; D009584:Nitrogen; D010100:Oxygen