title: Assessing the eligibility of a non-invasive continuous blood pressure measurement technique for application during total intravenous anaesthesia.
abstract: OBJECTIVE
  To assess the eligibility for replacement of invasive blood pressure as measured "within" the arterial vessel (IBP) with non-invasive continuous arterial blood pressure (cNIP) monitoring during total intravenous anaesthesia (TIVA), the ability of cNiP to track fast blood pressure changes needs to be quantified. A new method of statistical data analysis is developed for this purpose.
  
  
  METHODS
  In a pilot study on patients undergoing neurosurgical anaesthesia, mean arterial pressure MAPIBP measured with IBP was compared to MAPCNP measured by the CNAP Monitor 500 in ten patients (age: 63±13 a). Correlation analysis of changes of device differences ΔeMAP=ΔMAPCNP-ΔMAPIBP with changes of MAPIBP (ΔMAPIBP) during intervals of vasoactivity was conducted. An innovative technique, of linear trend analysis (LTA) applied to two signals, is described to perform this analysis without a priori knowledge of intervals of vasoactivity.
  
  
  RESULTS
  Analysis of ΔeMAP during vasoactivity revealed that ΔMAPCNP systematically underestimated ΔMAPIBP by 37%. This was confirmed in the complete data set using LTA technique showing a systematic, yet patient specific, underestimation in tracking ΔMAPIBP (16…120%).
  
  
  CONCLUSIONS
  The proposed LTA technique is able to detect systematic errors in tracking short-term blood pressure changes otherwise masked by established analysis. LTA may thus be a useful tool to assess the eligibility of cNIP to replace IBP during TIVA.
authors: Robert
authors: R
authors: Huhle
authors: Joachim
authors: J
authors: Siegert
authors: Fred
authors: F
authors: Wonka
authors: Christoph
authors: C
authors: Schindler
authors: Marcelo Gama
authors: MG
authors: de Abreu
authors: Thea
authors: T
authors: Koch
authors: Ute
authors: U
authors: Morgenstern
authors: Herman
authors: H
authors: Theilen
mesh_terms: D000768:Anesthesia, General / Q000379:methods*; D000771:Anesthesia, Intravenous / Q000379:methods*; D062186:Arterial Pressure / Q000187:drug effects / Q000502:physiology*; D001794:Blood Pressure / Q000502:physiology*; D001795:Blood Pressure Determination / Q000379:methods / Q000592:standards*; D006801:Humans; D008991:Monitoring, Physiologic / Q000592:standards*