Changes On Mean Systemic Filling Pressure And Microcirculation After a Fluid Challenge

Methods 24 post-operative cardiac patients were prospectively enrolled. Arterial pressure and central venous pressure was measured invasively. Cardiac output (CO) was measured with a non-calibrated LiDCOplus monitor (LiDCO, Cambridge). Pmsf was measured using the stop-flow arterial venous equilibrium pressure method (1). Sublingual microcirculation was recorded with CytoCam (Braedius Medical, Amsterdam, The Netherlands). Data was recorded at baseline, immediately after the fluid infusion, 5 and 10 minutes after the end of 4 ml/Kg of crystalloids infused in 5 minutes. At each time at least three sublingual microcirculation videos were acquired to assess total vessel density (TVD), microcirculatory flow index (MFI), proportion of perfused vessel (PPV), perfused vessel density (PVD) and microcirculatory heterogeneity index (MHI). Analysis was performed with AVA software v. 3.2 (MicroVision Medical, Amsterdam, The Netherlands). Responders are defined by an increase in CO greater than 10%.