主动脉弓部手术中单侧大脑灌注血流变化与神经系统并发症关系的分析

Analysis of the relationship between the hemodynamic changes during selective cerebral perfusion and postoperative neurological complications in aortic arch surgery

目的:通过经颅多普勒超声(TCD)监测主动脉弓部手术中大脑中动脉(MCA)的血流,评估选择性脑灌注(SCP)期间血流变化与术后神经系统并发症的关系。方法:自2010年9月至2011年1月,共有23例符合研究标准的主动脉夹层病例入选。术中均采用深低温停循环(DHCA)和单侧脑灌注的方法,通过TCD连续记录,从麻醉完成至体外循环结束这一过程中MCA血流改变,选取6个时间点进行比较。以非灌注侧流量下降比例分为4组(<10%,10%～20%,20%～30%,>30%),观察每组术后神经系统并发症的情况和术后早期死亡的情况。结果:本组患者在全流量体外循环期间,双侧MCA血流速度差异无统计学意义(P=0.565)。SCP期间,灌注侧(右侧)MCA血流较SCP之前相比,流速为基本无变化;非灌注侧(左侧)较SCP之前显著下降,主动脉开放后基本恢复至转机前水平。术后短暂神经系统损害发生率13.0%(3/23例),3例患者中,流量下降20%～30%组中1例(12.5%),>30%组中2例(50%)。无早期死亡和永久神经系统损伤。结论:选择性脑灌注可以满足主动脉弓部手术脑部供血;半侧脑灌注期间,灌注侧血流基本无变化,非灌注侧血流下降。安全阈值可能是30%,即下降30%之内是安全的。

Objective： This study tries to monitor the hemodynamic changes of middle cerebral artery （MCA） by transcranial Doppler sonography （TCD） in aortic arch surgery. Analysis of relationship between the hemodynamic changes during selective cerebral peffusion （SCP） and postoperative neurological complications. Methods： From September 2010 to January 2011,23 patients with aortic dissection undergoing aortic arch op- eration were included in this study. Every patient underwent profound hypothermia （DHCA） and selective cere- bral perfusion. Hemodynamic signals of bilateral MCA were monitored via TCD during operation. Data at 6 time-points were selected for analysis. All the patients were divided into four groups by the decline in the pro- portion of non-perfusion side flow（ 〈 10% ,10% -20% ,20% -30% , 〉30% ） , and all the postoperative neu- rological complications and early death after surgery were recorded in each group. Results： During the full flow of CPB, blood flow velocity of MCA at left and right side was no differences （ P = 0. 565 ）. During SCP, blood flow velocity of MCA at perfusion side （right side） was similar with blood flow velocity before SCP; and blood flow velocity of MCA at non-perfusion side （left side） was significant decreased compare with blood flow veloci-ty before SCP （P 〈 0. 001 ）. After the aorta was opened, blood flow velocity of MCA at both side gradually re- turned to normal, and nearly the same as blood flow velocity before CPB. Three patients （ 13.0% ） patients had temporary neurological dysfunction （TND） , in further detail, one patients were in the 20% - 30% groups （ 12.5% ）, two patients were in the 〉 30% groups （50%） ,no permanent neurological dysfunction （PND） and early death was observed. Conclusion： SCP in aortic arch operation can meet the blood supply to the brain; During SCP, blood flow velocity of MCA at peffusion side （right side） was similar to the blood flow velocity be- fore SCP; blood flow velocity of MCA at non-perfusion side （left side） was significant decreased compare with blood flow velocity before SCP. Less than 30% drop of blood flow velocity of MCA at non-perfusion side （ left side） may be safe for the Datients.