不同方法预测脓毒症患者容量反应性的准确性：超声法、PiCCO法与传统法的比较

Accuracy of different methods in predicting fluid responsiveness in septic patients ： a comparison be-tween ultrasound, PiCCO and traditional methods

目的比较超声法、脉搏指示连续心排血量监测（PiCCO）法和传统法预测脓毒症患者容量反应性的准确性。方法ICU需行机械通气治疗的脓毒症患者46例，性别不限，年龄18～72岁。采集静脉血样，采用化学发光法测定血浆B-型脑钠肽（BNP）浓度，记录CVP；采用超声法测定每搏量变异度（SVVTTE）、下腔静脉扩张指数（dIVC）和主动脉流速-时间指数变异度（ΔVTI）；采用PiCCO法测定SVVPiCCO和全心舒张末容积指数（GEDVI）。随后进行补液试验，根据补液试验后容量反应性将患者分为容量反应性阴性组和容量反应性阳性组。绘制上述指标预测容量反应性的受试者工作特征曲线（ROC），dIVC、ΔVTI和SVVPiCCO的阈值进行Kappa一致性检验，采用Bland-Altman法分析SVVTTE与SVVPiCCO的一致性。结果容量反应性阳性组24例，容量反应性阴性组22例；与容量反应阴性组比较，容量反应阳性组补液试验前血浆BNP浓度、CVP和GEDVI降低，SVVPiCCO、SVVTTE、dIVC和ΔVTI升高（P〈0.05）。各指标预测容量反应性的曲线下面积（95%可信区间）、灵敏度和特异度分别为：血浆BNP浓度：0.894（0.807～0.981）、81.8%和79.2%；CVP：0.859（0.752～0.965）、81.8%和79.2%；GEDVI：0.772（0.628～0.915）、72.7%和75.0%；SVVPiCCO：0.965（0.922～1.008）、95.8%和81.8%；SVVTTE：0.940（0.874～1.006）、91.7%和86.4%；dIVC：0.964（0.920～1.008）、83.3%和95.5%；ΔVTI：0.958（0.909～1.008）、87.5%和90.9%。dIVC和ΔVTI阈值与SVVPiCCO阈值的Kappa值分别为0.826和0.743（P〈0.01）。SVVTTE与SVVPiCCO的偏离度为0.209，95%可信区间为（－2.967～3.385）%，一致性界限为（－2.46～2.62）%。结论超声法和PiCCO法均可准确预测脓毒症患者容量反应性，且一致性良好，均优于传统方法。

ObjectiveTo compare the accuracy of ultrasound, pulse indicator continuous cardiac output monitoring （PiCCO） and traditional methods in predicting fluid responsiveness in septic patients.MethodsForty-six septic patients of both sexes, aged 18-72 yr, requiring mechanical ventilation treatment in the intensive care unit, were enrolled in the study.Venous blood samples were collected for determination of plasma B-type natriuretic peptide （BNP） concentrations by chemiluminescence assay, and central venous pressure （CVP） was recorded.Stroke volume variation （SVVTTE）, distensibility index of inferior vena cava （dIVC） and velocity time integral changes of aortic blood flow （ΔVTI） were measured by ultrasound method.SVVPiCCO and global end-diastolic volume index （GEDVI） were measured by PiCCO method.The patients were divided into negative fluid responsiveness group and positive fluid responsiveness group according to the fluid responsiveness after volume expansion.The receiver operating characteristic curves of the parameters mentioned above in predicting fluid responsiveness were drawn.A consistency check for dIVC, ΔVTI and SVVPiCCO thresholds was conducted by using Kappa statistics.The agreement between SVVTTE and SVVPiCCO was analyzed by the Bland-Altman analysis.ResultsThere were 24 patients in positive fluid responsiveness group and 22 patients in negative fluid responsiveness group.Compared with negative fluid responsiveness group, the plasma BNP concentration, CVP and GEDVI were significantly decreased, and SVVPiCCO, SVVTTE, dIVC and ΔVTI were increased before volume expansion in positive fluid responsiveness group （P〈0.05）. The area under the curve （95% confidence interval）, sensitivity and specificity of the plasma BNP concentration were 0.894 （0.807-0.981）, 81.8% and 79.2%, respectively, of CVP 0.859 （0.752-0.965）, 81.8% and 79.2%, respectively, of GEDVI 0.772 （0.628-0.915）, 72.7% and 75.0%, respectively, of SVVPiCCO 0.965 （0.922-1.008）, 95.8% and 81.8%, respectively, of SVVTTE 0.940 （0.874-1.006）, 91.7% and 86.4%, respectively, of dIVC 0.964 （0.920-1.008）, 83.3% and 95.5%, respectively, and of ΔVTI 0.958 （0.909-1.008）, 87.5% and 90.9%, respectively.The Kappa value for dIVC threshold and SVVPiCCO threshold was 0.826, and for ΔVTI threshold and SVVPiCCO threshold was 0.743 （P〈0.01）. The mean deviation of SVVTTE and SVVPiCCO was 0.209, 95% confidence interval （-2.967-3.385）%, and the limit of agreement （-2.46-2.62）%（P〈0.05）.ConclusionUltrasound and PiCCO methods can accurately predict fluid responsiveness, have a good agreement and are superior to the traditional method in septic patients.