title: Accuracy of an autocalibrated pulse contour analysis in cardiac surgery patients: a bi-center clinical trial.
abstract: BACKGROUND
  Less-invasive and easy to install monitoring systems for continuous estimation of cardiac index (CI) have gained increasing interest, especially in cardiac surgery patients who often exhibit abrupt haemodynamic changes. The aim of the present study was to compare the accuracy of CI by a new semi-invasive monitoring system with transpulmonary thermodilution before and after cardiopulmonary bypass (CPB).
  
  
  METHODS
  Sixty-five patients (41 Germany, 24 Spain) scheduled for elective coronary surgery were studied before and after CPB, respectively. Measurements included CI obtained by transpulmonary thermodilution (CITPTD) and autocalibrated semi-invasive pulse contour analysis (CIPFX). Percentage changes of CI were also calculated.
  
  
  RESULTS
  There was only a poor correlation between CITPTD and CIPFX both before (r (2) = 0.34, p < 0.0001) and after (r (2) = 0.31, p < 0.0001) CPB, with a percentage error (PE) of 62 and 49 %, respectively. Four quadrant plots revealed a concordance rate over 90 % indicating an acceptable correlation of trends between CITPTD and CIPFX before (concordance: 93 %) and after (concordance: 94 %) CPB. In contrast, polar plot analysis showed poor trending before and an acceptable trending ability of changes in CI after CPB.
  
  
  CONCLUSIONS
  Semi-invasive CI by autocalibrated pulse contour analysis showed a poor ability to estimate CI compared with transpulmonary thermodilution. Furthermore, the new semi-invasive device revealed an acceptable trending ability for haemodynamic changes only after CPB.
  
  
  BACKGROUND
  ClinicalTrials.gov: NCT02312505 Date: 12.03.2012.
authors.affiliation: Department of Anaesthesiology and Intensive Care Medicine, University Hospital Schleswig-Holstein, Campus Kiel, Schwanenweg 21, D-24105, Kiel, Germany. ole.broch@uksh.de.
authors.forename: Ole
authors.initials: O
authors.lastname: Broch
authors.affiliation: Department of Anaesthesiology and Critical Care, University Hospital Valencia, Avenida Blasco Ibanez 17, 46010, Valencia, Spain.
authors.forename: Jose
authors.initials: J
authors.lastname: Carbonell
authors.affiliation: Department of Anaesthesiology and Critical Care, University Hospital Valencia, Avenida Blasco Ibanez 17, 46010, Valencia, Spain.
authors.forename: Carlos
authors.initials: C
authors.lastname: Ferrando
authors.affiliation: Christian-Albrechts-University Kiel, Schleswig-Holstein, Germany.
authors.forename: Malte
authors.initials: M
authors.lastname: Metzner
authors.affiliation: Department of Anaesthesiology and Intensive Care Medicine, University Hospital Schleswig-Holstein, Campus Kiel, Schwanenweg 21, D-24105, Kiel, Germany.
authors.forename: Arne
authors.initials: A
authors.lastname: Carstens
authors.affiliation: Department of Anaesthesiology and Intensive Care Medicine, University Hospital Schleswig-Holstein, Campus Kiel, Schwanenweg 21, D-24105, Kiel, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Albrecht
authors.affiliation: Department of Anaesthesiology and Intensive Care Medicine, University Hospital Schleswig-Holstein, Campus Kiel, Schwanenweg 21, D-24105, Kiel, Germany.
authors.forename: Matthias
authors.initials: M
authors.lastname: Gruenewald
authors.affiliation: Department of Anaesthesiology and Intensive Care Medicine, University Hospital Schleswig-Holstein, Campus Kiel, Schwanenweg 21, D-24105, Kiel, Germany.
authors.forename: Jan
authors.initials: J
authors.lastname: Höcker
authors.affiliation: Department of Anaesthesiology and Critical Care, University Hospital Valencia, Avenida Blasco Ibanez 17, 46010, Valencia, Spain.
authors.forename: Marina
authors.initials: M
authors.lastname: Soro
authors.affiliation: Department of Anaesthesiology and Intensive Care Medicine, University Hospital Schleswig-Holstein, Campus Kiel, Schwanenweg 21, D-24105, Kiel, Germany.
authors.forename: Markus
authors.initials: M
authors.lastname: Steinfath
authors.affiliation: Department of Anaesthesiology and Intensive Care Medicine, University Hospital Schleswig-Holstein, Campus Kiel, Schwanenweg 21, D-24105, Kiel, Germany.
authors.forename: Jochen
authors.initials: J
authors.lastname: Renner
authors.affiliation: Department of Anaesthesiology and Intensive Care Medicine, Asklepios Hospital St. Georg, Hamburg, Germany.
authors.forename: Berthold
authors.initials: B
authors.lastname: Bein
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002138:Calibration; D002302:Cardiac Output / Q000502:physiology*; D002315:Cardiopulmonary Bypass; D005260:Female; D005858:Germany; D006439:Hemodynamics; D006801:Humans; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic / Q000379:methods*; D015203:Reproducibility of Results; D013030:Spain; D013815:Thermodilution