Thiel A, Zimmer M, Stertmann W A, Kaps M, Hempelmann G
Abteilung Anaesthesiologie und operative Intensivmedizin am Ostalbklinikum Aalen.
Anasthesiol Intensivmed Notfallmed Schmerzther. 1997 Dec;32(12):715-20. doi: 10.1055/s-2007-995141.
By means of transcranial Doppler sonography (TCD), microembolic signals (MES) representing embolic events can be registered during cardiac surgery and extracorporeal circulation in a considerable number of patients. We conducted the present study to determine the neuro-psychiatric consequences of MES.
25 patients scheduled for elective aorto-coronary bypass grafting (ACBG; n = 10) or aortic valve replacement (AVR; n = 15) were studied pre- and postoperatively with neuropsychiatric testing. Results were related to the number of MES noted intraoperatively. In addition, we registered the intraoperative changes of middle cerebral artery blood flow velocity, mean arterial pressure, arterial blood gases, haemoglobin and haematocrit. Statistics included t-test, two-way analysis of variance, Mann-Whitney-U-test and Spearman correlation with p < 0.05 considered significant.
Regarding demographic data and intraoperative parameters, both study groups (ACBG vs. AVR) were comparable except for age. AVR patients showed significantly more MES than those undergoing ACBG (p < 0.012) which was most pronounced in the late state of surgery (aortic clamp off; p < 0.0003). However, MES counts did not correlate with neuropsychiatric test results.
In contrast to recent reports, we were unable to show a deterioration of postoperative neuropsychiatric state related to high intraoperative MES count in our patients. Future TCD studies should focus on the differentiation between gaseous emboli and particles even in the clinical setting, as the latter may well play a major role for the development of cerebral dysfunction following cardiac surgery and extracorporeal circulation.
通过经颅多普勒超声（TCD）检查，在相当数量的心脏手术和体外循环患者中可记录到代表栓塞事件的微栓子信号（MES）。我们开展本研究以确定MES的神经精神后果。
对25例计划行择期主动脉冠状动脉搭桥术（ACBG；n = 10）或主动脉瓣置换术（AVR；n = 15）的患者在术前和术后进行神经精神测试。结果与术中记录的MES数量相关。此外，我们记录了术中大脑中动脉血流速度、平均动脉压、动脉血气、血红蛋白和血细胞比容的变化。统计学分析包括t检验、双向方差分析、Mann-Whitney-U检验和Spearman相关性分析，p < 0.05被认为具有统计学意义。
关于人口统计学数据和术中参数，除年龄外，两个研究组（ACBG组与AVR组）具有可比性。AVR患者的MES明显多于接受ACBG的患者（p < 0.012），这在手术后期（主动脉阻断解除；p < 0.0003）最为明显。然而，MES计数与神经精神测试结果无关。
与近期报道相反，我们未能在患者中显示出与术中高MES计数相关的术后神经精神状态恶化。未来的TCD研究应专注于即使在临床环境中区分气态栓子和颗粒，因为后者很可能在心脏手术和体外循环后脑功能障碍的发生中起主要作用。
