A Study On The Volumetric Reactivity Of Cardiac Function In Patients With Septic Shock By Rapid Ultrasound Assessment

Objective:Exploring the use of visual assessment of cardiac function under bedside echocardiography to assess volume responsiveness in patients with septic shock,in order to reveal its guiding role in clinical volume management treatment.Methods:60 patients with septic shock diagnosed and treated by ICU in the second affiliated Hospital of Nanchang University from July 2021 to January 2023 were selected.The basic clinical data of the patients were recorded.All patients underwent volume load test.The hemodynamic parameters of stroke volume(SV)and cardiac output(CO)before and after the test were monitored by bedside echocardiography.According to the change of CO before and after the test(CO),the patients were divided into capacity response group(CO ≥ 15%)and non-volume response group(CO < 15%).According to the indexes of left ventricular ejection fraction(LVEF),left atrial size,right ventricular size,interventricular septum motion,and right ventricular motion,which were visually rapidly evaluated by bedside transthoracic echocardiography before fluid infusion,they were divided into low LVEF group(EF<50%)and normal LVEF group(EF ≥ 50%),normal and enlarged left atrial size group,normal or slightly dilated right ventricular size group,and moderate and severe dilated right ventricle group Interventricular septum movement normal group and abnormal group,right ventricular movement normal group and abnormal group.Analyze the predictive value of visual evaluation of cardiac function for volume responsiveness assessment using the receiver operating characteristic curve(ROC curve).Results:Among the 60 patients,33(55%)had volumetric responsiveness(reactive group)and 27(45%)had non-volumetric reactivity(non-reactive group).After volume load test,the number of patients with high LVEF(LVEF ≥ 50%)in the response group was significantly higher than that in the non-response group(78.8% vs 33.3% score0.000).The number of patients with normal left atrial size in the response group was more than that in the non-response group(75.8% vs 40.7%).The number of patients with normal or slightly dilated right ventricle in the response group was more than that in the non-response group(87.9% vs 40.7%).The number of patients with normal interventricular septum movement in the response group was higher than that in the non-response group,but the difference was not statistically significant(81.8%VS66.7% score 0.178).The number of patients with normal right ventricular motion in the response group was more than that in the non-response group(84.8% VS48.1%penalty 0.002).The area under the ROC curve for predicting volumetric response with LVEF ≥ 50% was 0.727,the sensitivity was 78.8%,and the specificity was66.7%.The area under the ROC curve for normal prediction of left atrial size was0.675(95% CI:0.536～0.815 P < 0.05),the sensitivity was 75.8%,and the specificity was 59.3%.The area under the ROC curve predicted volume response by normal or mild right ventricular dilation was 0.736(95%CI:0.603～0.868 P < 0.01),the sensitivity was 87.9%,and the specificity was 59.3%.The area under the ROC curve for predicting volume response with normal right ventricular motion was 0.684(95%CI:0.544～0.823 P < 0.05),the sensitivity was 84.8%,and the specificity was51.9%.The area under the ROC curve of LVEF ≥ 50%,normal size of left atrium,normal or slightly dilated right ventricle and normal movement of right ventricle was0.802(95%CI:0.687～0.917 P < 0.01),the sensitivity was 87.8%,and the specificity was 66.7%.Conclusion:Bedside echocardiography can be used to guide volume management treatment in patients with septic shock by visually assessing cardiac function quickly.