选择性头部降温治疗对窒息新生儿心脏功能影响的研究

目的　研究亚低温治疗对窒息新生儿心脏功能的影响。方法　将 50例重度窒息足月新生儿分为治疗组 (2 3例 )和对照组 (2 7例 )。治疗组采用选择性头部降温方法 ,维持鼻咽温度在34 0℃± 0 .5℃ ,持续 72h ;对照组不进行亚低温治疗。超声心动图评估心脏收缩及舒张功能 ,并测定肌钙蛋白T(cardiactroponinT ,cTnT)的含量 ,以判断心肌细胞的损伤程度。 结果　 (1 )亚低温治疗组患儿心率与对照组比较 分别为 (1 0 3± 1 5)次 /min、(1 2 6± 1 4 )次 /min ,P <0 .0 5]明显降低 ,但无心律失常和低血压。 (2 )亚低温治疗组左室射血分数 (EF)、每搏量 (SV)、每分输出量 (CO)与对照组相比 ,差异无显著意义 (P均 >0 .0 5) ;两组左、右室舒张功能不全例数和肺动脉高压例数 ,差异也无显著意义 (P均 >0 .0 5)。 (3)亚低温治疗组和对照组cTnT水平分别为 (0 .47± 0 .1 5)ng/ml和 (0 .35±0 2 1 )ng/ml,差异无显著意义 (P >0 .0 5)。结论　选择性头部降温 (鼻咽温度 34℃ ,持续 72h)治疗新生儿窒息 ,未加重患儿心脏功能的损伤

Effects of hypothermia on cardiac function in neonates with asphyxia

OBJECTIVE: To study the effects of hypothermia on cardiac function in neonates after birth asphyxia. METHODS: Fifty term newborns with Apgar score < 5 at 5 minutes were randomly divided into no cooling group (normothermia group, NG; rectal temperature = 36.5 degrees C +/- 0.5 degrees C, n = 27) and cooling group (hypothermia group, HG; rectal temperature = 34.5 degrees C +/- 0.3 degrees C, nasopharyngeal temperature = 34.0 degrees C +/- 0.5 degrees C, n = 23). The selective head cooling was applied to maintain nasopharyngeal temperature at 34 degrees C for 72 h in hypothermia group. Systolic and diastolic function was detected at the end of treatment by echocardiogram. RESULTS: (1) The heart rate was obviously decreased during the hypothermia treatment, and there was a significant difference between HG and NG (103 +/- 15) bpm vs. (126 +/- 14) bpm, P < 0.05]. No cardiac arrhythmia and hypotension were found in all neonates. (2) There were no significant differences on the ejection fraction, stroke volume and cardiac output of left ventricle between the two groups (P > 0.05). No significant difference was found in the numbers of left and right ventricular diastolic dysfunction, pulmonary hypertension between the two groups (P > 0.05). (3) The level of cardiac troponin T (cTnT) in plasma was (0.47 +/- 0.15) ng/ml in HG, and (0.35 +/- 0.21) ng/ml in NG, and there was no significant difference between the two groups (P > 0.05). CONCLUSION: No significant cardiac dysfunction complication caused by the hypothermia treatment was found in term neonates after birth asphyxia.