Accuracy of changing rate of left ventricular outflow tract velocity time integral in predicting fluid responsiveness in septic patients

Abstract

Objective To evaluate the accuracy of changing rate of the left ventricular outflow tract velocity time integral (△VTI) in predicting fluid responsiveness in septic patients. Methods Twenty patients diagnosed with sepsis or septic shock and received mechanical ventilation, aged more than or equal to 18 yr, in whom the ventilation mode was SIMV plus VC, were enrolled in this study.The left ventricular outflow tract VTI, stroke volume (SV) and cardiac output (CO) were measured using ultrasound.Sodium potassium magnesium calcium and glucose injection 100 ml was intravenously infused over 1 min, ultrasound measurement was completed within 1 min, and then Sodium potassium magnesium calcium and glucose injection 400 ml was intravenously infused over 14 min.Fluid responsiveness was defined as increase in SV or CO more than 15% after infusion of 500 ml colloid solution, and then the patients were divided into responsiveness group and non-responsiveness group.△VTI, △SV and △CO were calculated after fluid replacement with 100 ml solution.The receiver operating characteristic curve was used to assess the accuracy of △VTI, △SV and △CO in predicting fluid responsiveness. Results The areas under the receiver operating characteristic curve of △VTI, △SV and △CO were 0.95, 0.91 and 0.88, respectively.When △VTI≥10% was used as the cut-off point, the sensitivity and specificity of △VTI in predicting fluid responsiveness was 90% and 80%, respectively. Conclusion △VTI can accurately predict the fluid responsiveness in septic patients. Key words: Blood flow velocity; Sepsis; Vascular capacitance