监测脑血流在诊断先天性心脏病婴儿围手术期脑损伤中的应用

摘要

Objective :To investigate the application of cerebral blood flow velocity (CBFV) variations in neurological disorders at perioperative period for congenital heart disease (CHD) infants with cardiopulmonary bypass (CPB) surgery.Method:A total of 31 infants who underwent open heart surgery with CPB were monitored for their CBFV by trans cranial Doppler (TCD).The aortic occlusion time,the serologic biomarkers for brain injury,S100B protein and neuron specific enolase (NSE) were recorded.The relationship between CBFV and postoperative neurological disorders was studied by multiple linear regression analysis.Results:The mean aortic clamping time was (60.72±28.72) min, at that time, the mean cerebral blood flow rate (Vm％) was 56±18 ％.The aortic clamping time was positively related to S100B protein levels at Tc, T6, T12 and T24 (r = 0.510, P =0.003; r =0.538 ,P= O.002; r =0.469 ,P =0.007; r =0.403 ,P =0.022).While Vm％ was negatively related to S100B protein levels at Tc and T6 ( r = -0.368,P = 0.038; r = -0.482, P = 0.005 ).Multiple linear regression analysis demonstrated that the aortic clamping time was positively correlated with S100B protein levels at Tc and T12( t = 2.221, P = 0.035; t = 2.163, P = 0.039) ,Vm％ was negatively correlated with NSE level at T24 (r =-0.449,P = 0.010).12/31 (38.7％) of patients suffered from transient post operative neurological disorders.The patients with Vm％ ＜50％ had higher risk for neurological disorders than those with Vm％ ≥50％ ,P=0.029.Conclusion:CPB could significantly decrease cerebral blood flow which may cause neurological disorders in CHD patients.TCD is practical for monitoring CBFV during peri-operative period for CHD surgery.%目的:通过监测体外循环过程中脑血流变化,研究其与脑损伤生化学指标的相关性,探讨脑血流降低在婴儿先天性心脏病(先心病)体外循环围手术期脑损伤中的应用.方法:对31例接受中低温全流量体外循环心脏手术的先心病患儿进行体外循环前后经颅多普勒脑血流监测,同时记录主动脉阻断时间.术前、术中、术后多时点测定脑损伤标记物S100B 蛋白(S100B)和神经元特异性烯醇化酶(NSE)数值.对全组患儿进行围手术期神经系统功能评价.应用多元线性回归分析,对术中脑血流变化、体外循环时间与脑损伤标记物测定值进行相关性分析.并初步探讨脑血流变化与术后神经系统异常之间的相关性.结果:本组患儿主动脉阻断时间为(60.72±28.72)min,主动脉阻断期间术中大脑中动脉脑血流流速稳定后的平均流速/术前麻醉后的大脑中动脉平均流速(Vm%)为(56±18)%.相关性分析表明,主动脉阻断时间与体外循环结束时点(Tc),术后6 h(T6),术后12 h(T12),术后24 h(T24) 时点的S100B值呈正相关(r=0.510,P=0.003;r=0.538,P＝0.002;r=0.469,P＝0.007;r=0.403,P=0.022),脑血流变化率与Tc、T6时点S100B值呈负相关(r=-0.368,P=0.038;r=-0.482,P=0.005);多元线性回归分析表明主动脉阻断时间与Tc及T12时点的S100B显著正相关(t=2.221,P＝0.035;t=2.163,P＝0.039).Vm%与T24时点的NSE呈负相关(r=-0.449,P=0.010);多元线性回归分析表明Vm%与T12时点的NSE显著负相关(t=-2.136,P＝0.042).全组31例患儿中,12例出现术后神经系统异常体征,Vm%＜50%患儿术后神经系统阳性体征的发生率较Vm%≥50%患儿明显增高,差异有统计学意义(P＝0.029).结论:体外循环过程中脑血流流速降低可能导致神经系统损伤,临床应用经颅多普勒监测围手术期脑损伤具有一定的实用价值.