硫喷妥钠与异丙酚在小儿心脏手术深低温停循环期间对脑缺血再灌注损伤的影响

Effects of thiopentone and propofol on cerebral ischemia-reperfusion injury during pediatric open heart surgery under deep hypothermic circulatory arrest

目的 观察婴幼儿先天性心脏病心内直视手术,深低温停循环期间给予硫喷妥钠、异丙酚对脑缺血再灌注损伤的影响。方法20例室间隔缺损伴肺动脉高压(VSD+PH)患儿随机分为硫喷妥钠5mg·kg-1(A组)、异丙酚2mg·kg-1(B组)和对照(C组)三组,于转流前(Ⅰ朗)、停循环时(Ⅱ期)、再灌注始(Ⅲ期)及术后24h(Ⅳ期)分别抽取颈内静脉、桡动脉血样做血气分析,并测定乳酸含量(LAC)及肌酸激酶BB(CKBB)和神经特异性烯醇化酶(NSE)的含量;计算脑动静脉氧含量差(Ca-vO2)、脑氧摄取率(Co2ER)。结果 Ⅲ期各组LAC水平最高,并以A组较为明显;脑氧代谢在Ⅱ期各组Ca-vO2、CO2ER均较其余各期低,其中B组下降最为明显,其次为A组和C组;Ⅳ期时,各组Ca-vO2、CO2ER均有所恢复。 各组在Ⅲ期CDBB和Ⅲ、Ⅳ期NSE均有上升趋势,B组增高幅度最低。结论 异丙酚用于深低温停循环期间对脑缺血再灌注损伤有保护作用。

Objective To investigate the effects of thiopentone and propofol on cerebral ischemia-reperfusion injury during open heart surgery under deep hypothermia circulatory arrest in infants and young children. Methods Twenty patients with VSD and pulmonary hypertension (13 male, 7 female), aged 3-23 months and weighing 4-11 kg were randomly divided into three groups: in group A thiopentone 5mg.kg was added in CPB machine when body temperature was reduced to 30℃ (n = 7); in group B propofol 2 mg.kg-1 was added ( n =8) and group C served as control ( n - 5). When rectal temperature was reduced to 20℃, CPB was stopped and intracardiac manipulation was started. Anesthesia was induced with midazolarn 0. 2mg.kg -1, fentanyl 20 μg.kg1 and vecuronium 0. 1mg.kg1 . After tracheal intubation the patients were mechanically ventilated and anesthesia was maintained with O2-N2O-isoflurane and intermittent boluses of fentanyl and vecuronium infusion (70μg.kg-1.h1). Radial artery was cannulated and internal jugular vein (IJV) was retrogradely cannulated until bulb, and blood samples were taken simultaneously from artery and IJV before CPB (T1 ), during circulatory arrest (T2 ) at the beginning of reperfusion ( T3 ) and 24h after operation ( T4 ) for blood gas analysis and determination of plasma concentration of lactic acid (LA), creatine kinase-BB (CKBB) activity and neuron-specific endase (NSE). Cerebral arterial-venous O2 content difference (Ca-vO2) and cerebral O2 extraction ratio (CO2ER) were calculated. Results Plasma concentration of lactic acid was increased at T3 in all three groups and was the highest in group A. Cerebral O2 metabolism decreased at T2 in all three groups and was the lowest in group B and resumed at T4 CKBB activity was increased at T3 and NSE level was increased at T3 and T4 in all 3 groups. The increase in CKBB activity and NSE level was slightest in group B. Conclusion Propofol can protect brain from ischemia-reperfusion injury in infants and young children during open heart surgery under deep hypothermic circulatory arrest.