床旁超声在监测感染性休克患者心排血量和容量反应性中的临床价值

Clinical value of point of care ultrasound on cardiac output and volume responsiveness in patients with septic shock

目的评价床旁超声在监测感染性休克患者心排血量(CO)和容量反应性中的临床价值。方法采用前瞻性调查研究方法。选择2020年11月25至2021年4月30日在郑州大学人民医院,河南省人民医院重症医学科因病情需要行脉搏指示连续心排血量(PiCCO)监测的24例感染性休克机械通气患者作为研究对象。记录患者的基本资料及实验室检查结果,采用PiCCO监测入组时(0 h)和入组后2、6、12、24、48 h的CO、每搏量变异度(SVV);同时行床旁经胸心脏超声测定左室流出道速度时间积分(VTI)、下腔静脉直径(dIVC),并计算CO、VTI变异率(△VTI)和dIVC变异率(△dIVC)。以PiCCO监测的数值为标准,对床旁超声测量的指标进行一致性检验及相关性分析。结果24例患者中有22例获得了满意的超声多普勒图像,入组患者心率(HR)、平均动脉压(MAP)及体温均符合感染性休克的病理生理特征。随治疗时间延长,患者HR、CO均逐渐下降,MAP逐渐升高,于入院后48 h达峰值或谷值,且与入组时比较差异有统计学意义〔HR(次/min):90.36±15.35比116.82±19.82,MAP(mmHg,1 mmHg=0.133 kPa):87.82±11.06比58.82±9.85,CO(L/min):4.80±0.56比6.78±1.31,均P<0.05〕。PiCCO和床旁超声测定的CO总体上具有良好的一致性〔分别为5.36(4.78,6.33)L/min和5.21(4.88,6.35)L/min〕,各时间点平均差异值为(-0.02±0.69)L/min,95%一致限范围为-1.35~1.34,且二者具有高度相关性(r_(s)=0.800,P<0.001);PiCCO测定的SVV和床旁超声测定的△dIVC具有良好一致性〔分别为18.00%(14.00%,24.00%)和21.00%(14.00%,25.75%)〕,各时间点平均差异值为(-3.16±6.89)%,95%一致限范围为-16.89~10.54,且二者具有中度相关性(rs=0.702,P<0.001)。PiCCO测定的SVV和床旁超声测定的△VTI具有良好一致性〔分别为18.00%(14.00%,24.00%)、16.00%(11.25%,20.75%)〕,各时间点平均差异值为(13.03±14.75),95%一致限范围为-1.72~27.78,且二者具有高度相关性(rs=0.918,P<0.001)。结论床旁超声能准确评估感染性休克患者的CO及容量反应性,且△VTI在评估容量反应性时优于△dIVC。

Objective To assess the value of point of care ultrasound on cardiac output(CO)and volume responsiveness in patients with septic shock.Methods A prospective investigation study was conducted.Twenty-four mechanical ventilation patients with septic shock who needed pulse-indicated continuous cardiac output(PiCCO)monitoring in the department of critical care medicine of Zhengzhou University People's Hospital,Henan Provincial People's Hospital from November 25,2020 to April 30,2021 were selected as the subjects,the patient's basic information and laboratory test results were recorded.PiCCO was used as standard to monitor CO and stroke volume variability(SVV)at 0,2,6,12,24 and 48 hours.At the same time,point of care transthoracic echocardiography(TTE)was used to measure velocity time integral(VTI)and inferior vena cava diameter(dIVC),the CO,VTI variation rate(△VTI)and dIVC variation rate(△dIVC)were calculated.Then,using the value monitored by PiCCO as the standard,the consistency and correlation analysis were carried out between point of care ultrasound with PiCCO.Results Twenty-two out of 24 patients obtained satisfactory ultrasound Doppler images,the heart rate(HR),mean arterial pressure(MAP)and body temperature of the enrolled patients were consistent with the pathophysiological characteristics of septic shock.With the extension of treatment time,HR and CO both gradually decreased,and MAP gradually increased,reaching a peak or trough at 48 hours after admission.The difference were statistically significant compared with the time of admission[HR(bpm):90.36±15.35 vs.116.82±19.82,MAP(mmHg,1 mmHg=0.133 kPa):87.82±11.06 vs.58.82±9.85,CO(L/min):4.80±0.56 vs.6.78±1.31,all P<0.05].The CO obtained by PiCCO and point of care ultrasound had good agreement[5.36(4.78,6.33)L/min and 5.21(4.88,6.35)L/min,respectively],the average difference value at each time point was(-0.02±0.69)L/min,the 95%agreement limit range was-1.35-1.34,and there was a high degree of correlation(r_(s)=0.800,P<0.001);The SVV by PiCCO and the△dIVC by point of care ultrasound were in good agreement[18.00%(14.00%,24.00%)and 21.00%(14.00%,25.75%),respectively],the average difference value at the time point was(-3.16±6.89)%,the 95%agreement limit range was-16.89-10.54,and there was a moderate correlation(rs=0.702,P<0.001);The SVV by PiCCO and the△VTI by point of care ultrasound were in good agreement[18.00%(14.00%,24.00%)and 16.00%(11.25%,20.75%),respectively],the average difference value at each time point was(13.03±14.75)%,and the 95%agreement limit range was 1.72-27.78,and there was a high correlation(rs=0.918,P<0.001).Conclusion Point of care ultrasound can accurately assess CO and volume responsiveness of patients with septic shock,and the△VTI is better than the△dIVC in assessing volume responsiveness.