We propose that complex (nonlinear) fluctuations of hemodynamic variables (including systemic blood pressure parameters) during cardiovascular surgery contain information relevant to risk assessment and intraoperative management. Preliminary analysis of a pilot study supports the feasibility and potential merits of performing a larger, prospective study to assess the clinical utility of such new dynamical measures and to evaluate their potential role in enhancing contemporary approaches to risk assessment of major adverse events.
Keywords: beat by beat.; blood pressure; blood pressure variability; cardiac surgery; dynamic biomarkers; instability; multiscale entropy; nonlinear analysis; outcomes; perioperative; risk index.