新生儿窒息后选择性头部降温的实施和安全性研究

Research on safety of mild hypothermia via selective head cooling in term neonates with perinatal asphyxia

目的:评估选择性头部降温治疗围产期窒息后新生儿缺氧缺血性脑损伤的实施及其安全性。方法:选取符合以下条件的新生儿:①孕周≥37周。②出生后首次动脉血气分析BD>15mEq/L,或生后5minApgar评分<6分。③出生后6h内出现临床神经系统症状和体征,随机分为亚低温组(n=40)和对照组(n=38)。亚低温组采用选择性头部降温方法,维持直肠温度于34～35℃,持续72h;6h内常规应用苯巴比妥负荷量20～30mg·kg-1,再用维持量5mg·kg-1·d-1对症止痉治疗,予多巴胺5μg·kg-1·min-1,维持3d。对照组维持正常体温,其他治疗相同。动态监测血压、心率、血气分析、血糖、电解质、心、肝、肾等功能。结果:两组各有40例和38例完成治疗;亚低温组直肠温度降至目标温度35℃所需时间为(55±20)min,治疗过程中心率平均下降至(105±6)次/min,对照组(140±11)次/min,两组差异有显著性(P<0.01);但两组平均动脉压保持在正常范围(45±5)mmHg;两组血肌钙蛋白-I、肝功能、肌酐、尿素氮虽有升高,两组比较差异无显著性(P>0.05)。结论:对围产期窒息后新生儿实施选择性头部降温维持直肠温度于34～35℃是安全的,可应用于具有重症监护条件的新生儿病房。

Objective： To observe the potential side effects of the mild hypothermia and make a pilot study with regard to the clinical safety. Methods： Full tern newborns who had 5 minute Apgar scores 〈 6 or first arterial blood gas BD 〉 15 mEq/L, and with the clinical signs of encephalopathy were enrolled within 6 hours after birth. Patients were randomized to receive mild hypothermia treatment via selective head cooling for a total of 72 hours oe receive routine treatment as a control. All were started with a loading dose of 20 - 30 mg·kg^-1 of phenobarbital, and 5μg·kg^-1·min^-1 of dopamine for 72 h. All newborns were monitored and analyzed for blood gas, electrolytes, blood glucose, troponin-I, serum creatinine, urea nitrogen, hepatic function and the hematological data. Results： A total of 78 patients （40 hypothermia, 38 control） completed the study. In the hypothermic group, it took an average of （55 ± 20） rain to cool the temperature down to the target level. The heart rates in the hypothermic group were significantly lower [（105 ± 6）/min] than that of the control group [（140 ± 11）/min] （P 〈0.01）. Hoover, the mean blood pressures were maintained （45 ± 5） mmHg by the routine use of dopamine.There was no difference between the two groups for electrolytes, liver enzymes, blood urea nitrogen and creatinine levels, blood coagulation functions during 72 h period. Conclusion： The results suggest that mild hypothermia via selective head cooling in term neonates with perinatal asphyxia is relatively safe and can be used in a regular NICU setting, it does not aggravate cardiac, hepatic, renal, coagulation dysfunction.