经颅多普勒超声在VA-ECMO患者脑血流动力学评估中的观察性研究

Observational Study of Transcranial Doppler Ultrasound in the Evaluation of Cerebral Hemodynamics in Patients with VA-ECMO

关键词:  经颅多普勒超声  体外膜肺氧合  脑血流动力学  无创脑监测  脑损伤

Key words:  transcranial Doppler ultrasound  extracorporeal membrane oxygenation  cerebral hemodynamics  noninvasive brain monitoring  brain injury

摘要:

采用经颅多普勒超声（Transcranial Doppler Ultrasound，TCD）监测动脉静脉体外膜肺氧合（Venoarterial Extracorporeal Membrane Oxygenation，VA-ECMO）患者的脑血流动力学，分析其脑血流参数与血压、体外膜肺氧合（Extracorporeal Membrane Oxygenation，ECMO）流量变化的关系，以及脑血流动力学改变与患者神经系统并发症发生的关系，为指导临床治疗及判断早期预后提供依据。转机后对VA-ECMO患者进行双侧大脑中动脉（Middle Cerebral Arterys，MCA）血流监测，记录脑血流与平均动脉压（Mean Arterial Pressure，MAP）、ECMO流量情况，根据脉压差（Pulse Pressure，PP）是否大于10 mmHg分为两组，比较两组患者脑血流动力学情况及ECMO流量特点，以及脑血流改变与患者急性神经系统并发症发生的相关性。结果表明：PP≤10 mmHg组的VA-ECMO患者MAP低于PP>10 mmHg组[（59.44±15.54） mmHg vs （77.93±8.68） mmHg，P＝0.008]，其ECMO流量高于PP>10 mmHg组[（4.29±0.88） L/min vs （3.37±0.74） L/min，P＝0.041]，此时MCA的收缩期流速、平均流速、脑血流指数相较于PP>10 mmHg组下降，但差异无统计学意义。两组患者MCA舒张期流速无显著性差异。PP≤10 mmHg组患者右侧MCA搏动指数、阻力指数均低于PP>10 mmHg组，差异有统计学意义（P<0.05）。两组的神经系统并发症发生率差异无统计学意义(P>0.05）。心泵功能衰竭且脉压差低于10 mmHg的患者，提高VA-ECMO流量可维持其脑血流，利用TCD监测VA-ECMO患者脑血流变化并指导临床诊疗具有可行性。

Abstract:

In this study, Transcranial Doppler Ultrasound (TCD) was used to monitor cerebral hemodynamics in patients with Venoarterial Extracorporeal Membrane Oxygenation (VA-ECMO). The relationship between cerebral blood flow parameters and changes in blood pressure, extracorporeal membrane oxygenation (ECMO) flow was analyzed, as well as the relationship between cerebral hemodynamic changes and neurological complications in patients, providing the basis for guiding clinical treatment and judging early prognosis. After the beginning of VA-ECMO, the blood flow of Middle Cerebral Arterys (MCA) was monitored. And the cerebral blood flow, Mean Arterial Pressure (MAP) and ECMO flow were also recorded. According to whether the Pulse Pressure (PP) difference was greater than 10 mmHg, the patients were divided into two groups. The cerebral hemodynamics and ECMO flow characteristics of the two groups were compared, and the correlation between cerebral blood flow changes and the occurrence of acute neurological complications in patients was compared. The results showed that the MAP of VA-ECMO patients in the PP ≤ 10 mmHg group was lower than that in the PP>10 mmHg group[(59.44±15.54) mmHg vs (77.93±8.68) mmHg, P=0.008], and the ECMO flow was higher than that in the PP>10 mmHg group[(4.29 ±0.88) L/min vs (3.37±0.74) L/min, P=0.041]. At this time, the systolic velocity, mean velocity and cerebral blood flow index of MCA decreased compared with PP>10 mmHg group, but the difference was not statistically significant. There was no significant difference in MCA diastolic flow rate between the two groups. The right MCA pulsatility index and resistance index of patients in PP ≤ 10 mmHg group were lower than those in PP>10 mmHg group, and the difference was statistically significant (P<0.05). There was no significant difference in the incidence of neurological complications between the two groups (P>0.05). In patients with cardiac pump failure and pulse pressure lower than 10 mmHg, increasing VA-ECMO flow can maintain cerebral blood flow. It is feasible to use TCD to monitor the changes of cerebral blood flow in patients with VA-ECMO and guide clinical diagnosis and treatment.