目的:探讨床旁经胸超声心动图(TTE)在脓毒性休克患儿容量反应性评估中的应用价值。方法:前瞻性纳入2017年1月至2020年6月入住PICU需机械通气的脓毒性休克患儿共41例，年龄1～5岁。在完全机械通气、充分镇静镇痛、无自主呼吸情况下(潮气量8～10 mL/kg)，给予患儿容量负荷试验。容量负荷前后测量患儿的心率(HR)、平均动脉压(MAP)、中心静脉压(CVP)、射血分数(EF)等一般血流动力学指标，同时无创心输出量监测仪(NICOM)和TTE测量心脏指数(CI)、每搏量指数(SVI)、每搏量变异度(SVV)；此外，TTE测量主动脉流速时间积分变异度(ΔVTI )、下腔静脉变异度(ΔIVC)、下腔静脉膨胀指数(dIVC)。以ΔSVIn NICOM≥15%定义为有容量反应性，将患儿分为有容量反应组和无容量反应组。统计分析SVVn TTE、ΔVTI、ΔIVC、dIVC、ΔCVP、SVVn NICOM预测容量反应性的价值。n 结果:(1)有容量反应组23例，无容量反应组18例。两组患儿的一般血流动力学指标HR、MAP、CVP、EF、CIn NICOM、CIn TTE无统计学差异(n P>0.05)。(2)有容量反应组补液后HR、MAP、CI、SVI、CVP均较补液前改善(n P0.05)。(3)容量负荷前，有容量反应组的SVVn TTE、ΔVTI 、ΔIVC、dIVC均较无容量反应组高(n P均0.05). (2) In response group, HR, MAP, CI, SVI and CVP were all improved after volume expansion(n P0.05). (3)Before the volume expansion, SVVn TTE, ΔVTI, ΔIVC, and dIVC in response group were higher than those in non-response group( n P<0.001). After volume expansion, these indicators were significantly reduced in response group.In non-response group, only ΔIVC significantly reduced after volume expansion.(4) The receiver-operating characteristic curve analysis showed that the area under the curve of SVVn TTEand ΔVTI was 0.971, with 12.04% as the threshold, the sensitivity was 0.957 and the specificity was 0.944. The area under the curve of ΔIVC was 0.981, with 25.98% as the threshold, the sensitivity was 0.870 and the specificity was 1.000.The area under the curve of dIVC was 0.980, with 29.86% as the threshold, the sensitivity was 0.870 and the specificity was 1.000. The area under the curve of ΔCVP was 0.778, with 2.5 cmH n 2O(1 cmHn 2O=0.098 kPa) as the threshold, the sensitivity was 0.913 and the specificity was 0.556. The area under the curve of SVVn NICOMwas 0.874, with 12.50% as the threshold, the sensitivity was 0.869 and the specificity was 0.778.n Conclusion:The dynamic indexes SVV, ΔVTI, ΔIVC and dIVC monitored by TTE have good accuracy in evaluating children′s volume responsiveness, among which the accuracy of ΔIVC and dIVC is relatively the highest; the value of ΔCVP in predicting volume responsiveness is limited.