title: A novel approach to measure cardiac output noninvasively: a comparison with the thermodilution method on critical care patients.
abstract: OBJECTIVE
  To compare the accuracy and reliability of cardiac output (CO) measurement by a Noninvasive Hemodynamic Analyzer (NHA) to the thermodilution cardiac output (COTD) technique in ICU patients of cardiac condition.
  
  
  METHODS
  ICU retrospective data collected in a 700-bed university-affiliated regional medical center. The data results from 203 patients who required invasive hemodynamic monitoring for clinical and/or surgical management.
  
  
  RESULTS
  The ranges of the two CO measurements were: CO(TD) = 2.06 to 8.8 l/min and CO(NHA) = 2.06 to 8.46 l/min, respectively. The Mean and SD of CO(NHA) = 4.819 l/min +/- 1.053 was near to CO(TD) = 4.902 l/min +/- 1.421. Variance was better for CO(NHA) = 1.110 l/min compared to CO(TD) = 1.421 l/min. Median of CO(NHA) showed 4.813 l/min and CO(TD) = 4.660 l/min. Bias was 0.083 l/min with 95% Confidence Interval (Precision): -0.26 to 0.040, and 95% Limits of Agreement was between -1.661 to 1.827 l/min.
  
  
  CONCLUSIONS
  The results of this retrospective study indicate that the CO(NHA) technique may be a promising screening method. Additional studies are needed to explore its diagnostic trending capability. This noninvasive CO technique has been proven to be clinically accurate and may be applicable for telemedicine applications.
authors.affiliation: Reston Noninvasive Hemodynamic Center 1712 Clubhouse Road, Suite 103 Reston, Virginia 20190, USA.
authors.forename: John
authors.initials: J
authors.lastname: Kabal
authors.forename: Bruce K
authors.initials: BK
authors.lastname: Lagerman
mesh_terms: D000465:Algorithms; D002302:Cardiac Output; D003422:Critical Care; D003936:Diagnosis, Computer-Assisted; D005260:Female; D006334:Heart Function Tests / Q000379:methods*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D013815:Thermodilution