右美托咪定对小儿先天性心脏病体外循坏术中脑氧代谢及近远期认知功能的影响

目的 探讨右美托咪定(dexmedetomidine,Dex)对小儿先天性心脏病(congenital heart disease,CHD)CPB术中脑氧代谢及近远期认知功能的影响. 方法 择期行CPB手术的CHD患儿84例,采用随机数字表法分为观察组和对照组(每组42例).观察组麻醉诱导后予以吸入2.5％七氟醚及Dex 0.4 μg· kg-1·h-1术中维持麻醉,对照组麻醉诱导后予以吸入2.5％七氟醚维持麻醉,分别在患儿CPB开始前(T1)、升主动脉开放时(T2)、CPB结束10 min(T3)、术后6 h(T4)4个时间点分别采集3 ml的桡动脉及静脉球部血样进行血气分析,计算颈内静脉血氧饱和度(jugular venous oxygen saturation,SjvO2)、动脉-颈内静脉血氧含量差值(arterial venous oxygen content difference,Da-jvO2)以及脑氧摄取率水平(cerebral extraction of oxygen,CERO2),并在术前、术后3d、术后3个月、术后1年行简易智力状况调查(mini-mental state examination,MMSE)评分. 结果 两组患儿T2时SjvO2高于T1时,而Da-jvO2、CER02低于T1时,差异有统计学意义(P＜0.05);T2时观察组SjvO2高于对照组,而Da-jvO2、CER02低于对照组,差异有统计学意义(P＜0.05),而T3、T4时两组患儿SjvO2、Da-jvO2、CERO2的差异无统计学意义(P＞0.05).两组患儿术前MMSE评分差异无统计学意义(P＞0.05);观察组术后4d和术后3个月的MMSE评分(26.5±1.5)、(27.6±1.6)分]显著高于对照组(24.3±1.3)、(25.8±1.5)分],差异有统计学意义(P＜0.05);两组术后1年的MMSE评分差异无统计学意义(P＞0.05). 结论 小儿CHD CPB术中应用Dex具有一定的脑保护作用,能改善脑氧代谢以及术后短期认知功能.

Effects of dexmedetomidine on cerebral oxygen metabolism and postoperative cognitive function during cardiopulmonary bypass of pediatric congenital heart disease surgery

Objective Exploring the effects of dexmedetomidine (Dex) on cerebral oxygen metabolism and postoperative cognitive function during cardiopulmoary bypass of pediatric congenital heart disease (CHD) surgery.Methods Eighty-four children with cardiopulmonary bypass of CHD surgery were randomly divided into observation group and control group (n=42).2.5％ sevoflurane and Dex 0.4 μg·kg-1·h-1 was applied during maintenance of anesthesia in observation group,while only 2.5％ sevoflurane was applied in control group.At the time points of before beginning cardiopulmonary bypass (T1),of the ascending aorta was open(T2),of ending cardiopulmonary bypass(T3) and of 6 hours after operation(T4),blood from radial artery and right jugular bulb were harvested for blood gas analysis.The jugular venous oxygen saturation (SjvO2),arterial venous oxygen content difference (Da-jvO2) and cerebral extraction of oxygen (CERO2) were calculated according blood gas analysis.The mini-mental state examination (MMSE) score were evaluated before and 4 day,3 month and 1 year after surgery.Results The SjvO2 of T2 were higher than SjvO2 of T1 in two groups,but Da-jvO2 and CERO2 were lower than Da-jvO2 and CERO2 of T1.The differences were statistically significant (P＜0.05).The SjvO2 in observation group at T2 was higher than SjvO2 at T2 in control group,but Da-jvO2 and CERO2 at T2 were lower than those in control group.The differences were statistically significant (P＜0.05).There were no significant differences in SjvO2,Da-jvO2,CERO2 at T3,T4 between two groups (P＞0.05).There were no significant differences in preoperative MMSE scores between two groups (P＞0.05).The MMSE scores in observation group at 4 day and 3 month after surgery were (26.5±1.5),(27.6±1.6),which were significantly higher than those in control group (24.3±1.3),(25.8±1.5)],and the differences were statistically significant (P＜0.05).But there were no significant differences in MMSE scores at 1 year after surgery between two groups (P＞0.05).Conclusions Dex could improve cerebral oxygen metabolism and postoperative cognitive function during cardiopulmonary bypass of pediatric CHD surgery.