The ability of the Vigileo-FloTrac system to measure cardiac output and track cardiac output changes during one-lung ventilation.

This study was aimed at comparing the cardiac output (CO) measured by the Vigileo™-FloTrac™ system with that estimated by the thermodilution pulmonary artery catheter (PAC) during one-lung ventilation (OLV) and determining the reliability of this system in tracking phenylephrine-induced CO changes during OLV. Sixteen patients scheduled for descending aorta replacement were enrolled. The study was performed 30 min after starting OLV under stable hemodynamic conditions. We recorded hemodynamic variables, CO measured by PAC thermodilution (ICO), CO measured by Vigileo™-FloTrac™ system (Version 3.02, Edwards Lifesciences, Irvine, CA, USA) (APCO), and systemic vascular resistance index (SVRI) before (T0) and after (T1) phenylephrine (100 μg) administration. We used Bland-Altman analysis to compare ICO and APCO. Polar plot and four-quadrant plot were used to assess the tracking ability of the Vigileo™-FloTrac™ system against ICO after administration of phenylephrine. Ninety hemodynamic interventions were performed. Bland-Altman analysis revealed that the mean bias between APCO and ICO was 0.05 L/min and the percentage error, 46.9 %. Four-quadrant plot analysis showed a concordance rate of 24.7 %, while polar plot analysis showed that the concordance rate was 13.3 %; the angular bias, -45.9°; radial limit of agreement, 85.3°. The bias between APCO and ICO was significantly correlated with the SVRI value (p < 0.001, r(2) = 0.822). The reliability of the Vigileo™-FloTrac™ system during OLV to estimate CO and track phenylephrine-induced CO changes was not acceptable.