Shao Xuebo, Chen Qi, Tang Weidong, Zhu Lijun, Lu Enkui
Department of Intensive Care Unit, the First People's Hospital of Fuyang Hangzhou, Hangzhou 311400, Zhejiang, China. Corresponding author: Shao Xuebo, Email:
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue. 2021 Sep;33(9):1105-1109. doi: 10.3760/cma.j.cn121430-20210706-01013.
To investigate the value of monitor carotid velocity time integral (VTI) and corrected flow time (FTc) by bedside ultrasound before and after passive leg raising (PLR) in predicting fluid responsiveness in critically ill patients.
A prospective observational study was conducted. Fifty patients with critical illness admitted to the First People's Hospital of Fuyang Hangzhou from January 2020 to March 2021 were enrolled. The clinical data including the gender, age, body mass index (BMI), acute physiology and chronic health evaluation II (APACHE II) score, and the duration of mechanical ventilation were recorded. The changes of carotid VTI and FTc were measured by bedside ultrasound, and the values of heart rate, mean arterial pressure (MAP), central venous pressure (CVP), stroke volume index (SVI), and intrathoracic blood volume index (ITBVI) were measured by pulse indicated continuous cardiac output (PiCCO) monitor before and after PLR in all patients. According to the changes of SVI before and after PLR, the patients were divided into fluid responsiveness positive group with the change rate of SVI ≥ 15% and fluid responsiveness negative group with the change rate of SVI < 15%. The differences in the values of VTI, FTc, CVP, and ITBVI obtained before and after PLR (ΔVTI, ΔFTc, ΔCVP and ΔITBVI) were calculated and then compared between the two groups. The predictive values of these indicators on fluid responsiveness in critically ill patients were analyzed by receiver operator characteristic curve (ROC curve), and their relationship with the difference in SVI (ΔSVI) obtained before and after PLR was evaluated by Pearson correlation analysis.
Fifty patients were all enrolled in this study, in which 27 patients were fluid response and 23 patients were fluid nonresponse. Basic clinical data were not different between the two groups. The values of ΔVTI, ΔFTc, ΔCVP, and ΔITBVI in fluid response were all significantly higher than those in fluid nonresponse [ΔVTI (cm): 2.07±1.16 vs. 0.67±0.86, ΔFTc (ms): 4.00±6.10 vs. 0.01±2.26, ΔCVP (cmHO, 1 cmHO = 0.098 kPa): 1.67±1.14 vs. 1.00±1.17, ΔITBVI (mL/m): 98±69 vs. 48±70, all P < 0.05]. ROC curve analysis showed that ΔVTI, ΔFTc, ΔCVP and ΔITBVI were all positive for predicting fluid responsiveness, their area under ROC curve (AUC) and 95% confidence interval (95%CI) were 0.870 (0.769-0.972), 0.694 (0.547-0.841), 0.684 (0.535-0.832) and 0.709 (0.564-0.855), respectively. When using ΔVTI 0.92 cm, ΔFTc 1.45 ms, ΔCVP 1.50 cmHO and ΔITBVI 44.50 mL/m as the threshold values, the sensitivities were 96.3%, 63.0%, 44.4% and 81.5%, and the specificities were 65.2%, 78.3%, 82.6% and 56.5%, respectively, in which the predictive value of ΔVTI was the largest. Pearson correlation analysis indicated that ΔVTI, ΔFTc, ΔCVP, and ΔITBVI were positively associated with ΔSVI (r values were 0.971, 0.334, 0.440, 0.650, P values were 0.000, 0.018, 0.001, 0.000, respectively).
Carotid ΔVTI and ΔFTc monitored by bedside ultrasound before and after PLR could be as effective as conventional indicators in predicting fluid responsiveness in critically ill patients, and the predictive value of ΔVTI was better than others.
探讨被动抬腿（PLR）前后床边超声监测颈动脉速度时间积分（VTI）和校正血流时间（FTc）对危重症患者液体反应性的预测价值。
进行一项前瞻性观察性研究。纳入2020年1月至2021年3月在杭州市富阳区第一人民医院收治的50例危重症患者。记录患者的性别、年龄、体重指数（BMI）、急性生理与慢性健康状况评分系统II（APACHE II）评分及机械通气时间等临床资料。采用床边超声测量PLR前后颈动脉VTI和FTc的变化，所有患者采用脉搏指示连续心输出量（PiCCO）监测仪测量PLR前后心率、平均动脉压（MAP）、中心静脉压（CVP）、每搏量指数（SVI）和胸腔内血容量指数（ITBVI）。根据PLR前后SVI的变化，将患者分为液体反应阳性组（SVI变化率≥15%）和液体反应阴性组（SVI变化率<15%）。计算两组PLR前后VTI、FTc、CVP和ITBVI的差值（ΔVTI、ΔFTc、ΔCVP和ΔITBVI）并进行组间比较。采用受试者工作特征曲线（ROC曲线）分析这些指标对危重症患者液体反应性的预测价值，采用Pearson相关性分析评估其与PLR前后SVI差值（ΔSVI）的关系。
50例患者均纳入本研究，其中液体反应阳性27例，液体反应阴性23例。两组患者基础临床资料差异无统计学意义。液体反应阳性组的ΔVTI、ΔFTc、ΔCVP和ΔITBVI值均显著高于液体反应阴性组[ΔVTI（cm）：2.07±1.16比0.67±0.86，ΔFTc（ms）：4.00±6.10比0.01±2.26，ΔCVP（cmH₂O，1 cmH₂O = 0.098 kPa）：1.67±1.14比1.00±1.17，ΔITBVI（mL/m）：98±69比48±70，均P<0.05]。ROC曲线分析显示，ΔVTI、ΔFTc、ΔCVP和ΔITBVI对液体反应性预测均为阳性，其ROC曲线下面积（AUC）及95%置信区间（95%CI）分别为0.870（0.769 - 0.972）、0.694（0.547 - 0.841）、0.684（0.535 - 0.832）和0.709（0.564 - 0.855）。以ΔVTI 0.92 cm、ΔFTc 1.45 ms、ΔCVP 1.50 cmH₂O和ΔITBVI 44.50 mL/m为阈值时，敏感性分别为96.3%、63.0%、44.4%和81.5%，特异性分别为65.2%、78.3%、82.6%和56.5%，其中ΔVTI预测价值最大。Pearson相关性分析表明，ΔVTI、ΔFTc、ΔCVP和ΔITBVI与ΔSVI呈正相关（r值分别为0.971、0.334、0.440、0.650，P值分别为0.000、0.018、0.001、0.000）。
PLR前后床边超声监测的颈动脉ΔVTI和ΔFTc在预测危重症患者液体反应性方面与传统指标效果相当，且ΔVTI预测价值优于其他指标。
