Accuracy of an autocalibrated pulse contour analysis in cardiac surgery patients: a bi-center clinical trial (BMC Anesthesiology)

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 (CI TPTD ) and autocalibrated semi-invasive pulse contour analysis (CI PFX ). Percentage changes of CI were also calculated. Results: There was only a poor correlation between CI TPTD and CI PFX both before (r 2  = 0.34, p