Variability of left ventricle outflow tract VTI during breathing cycle may predict fluid responsiveness in the postoperative period for non-cardiac spontaneously breathing patients

Abstract

Introduction: Different studies show controversial results while discussing which echocardiography parameter is the best to assess fluid responsiveness. The aims of the study were to evaluate the feasibility of echocardiography monitoring in postoperative unit and to assess diagnostic value of different parameters obtained by focused assessed transthoracic echocardiography (FATE) to control non-cardiac patients’ postoperative fluid therapy. Methods: 40 patients who underwent major abdominal surgery and had reduced arterial blood pressure were included in the prospective study. The echocardiography measurements were taken before and immediately after fluid challenge of 500 ml of crystalloids. Positive fluid responsiveness was defined by an increase in stroke volume (SV) of at least 15%. Results: FATE monitoring is feasible in postoperative unit. The identification of fluid responsiveness by clinical signs was significantly lower compared to echocardiography data (p=0.034). Variability of left ventricle outflow tract (LVOT) velocity time integral (VTI) during breathing cycle prognosis fluid responsiveness AUC of the ROC was 0.881. The mitral E wave, E/A ratio and IVC index prognoses fluid responsiveness in spontaneously breathing patients (p=0.006; p<0.001; p<0.001). CI seemed to be not suitable for prognosis of fluid responsiveness (p=0.214). There was no difference between infusion therapy in responders and non-responders neither during operation 2167 ml and 1678 ml (p=0.13) respectively nor in postoperative period 1500 ml and 1678 ml (p=0.344). After FATE the strategy of infusion therapy was changed in 14 (35%) patients. Conclusions: LVOT VTI variability of more than 10% in spontaneously breathing patients had the highest sensitivity and comparable specificity among the parameters used for identification of fluid responders by FATE.