脓毒症小鼠死亡高发期心功能变化的动态观察

目的:研究脓毒症小鼠死亡高发期心功能的动态变化。方法:应用高分辨小动物超声成像系统对正常雄性昆明小鼠先行超声心动图检查(0h)后行盲肠结扎穿孔术,术后分5个时点(12h,24h,36h,48h,168h)对小鼠进行超声心动图检查,168h(7d)仍存活的小鼠视为存活动物,每只小鼠均进行编号,确保对其进行连续观察。结果:小鼠在盲肠结扎穿孔术早期即出现回心血量显著减少,左室舒张末期容积在CLP术后24h达最低点,较术前下降了46%。小鼠在脓毒症的刺激下心脏功能出现明显的代偿性改变,尤其以收缩功能最强,舒张功能的代偿弱于收缩功能,CLP术后24h,射血分数和短轴缩短率较术前分别增加了27%和39%,E/A比值和E峰减速时间较术前减少了30%和25%。结论:强大的心脏代偿功能是脓毒症小鼠得以存活的重要原因之一。重视心脏代偿功能尤其是舒张功能的保护对提高生存率有重要意义。

Dynamic changes of mouse cardiac functions in early stage of sepsis induced by CLP

AIM: To detect the changes of cardiac functions of septic mice in the early stage of sepsis. METHODS: Health male Kunming mice were used in the study. The techniques of 2D, M-mode and Doppler echocardiography were applied to evaluate the cardiac functions before cecal ligation and puncture(CLP) as baseline and at time points of 12 h, 24 h, 36 h, 48 h and 168 h after CLP. The mice survived for 168 h(7 d) were considered as survivals. RESULTS: Compared to the baseline at the time point of 24 h after CLP, the blood volumes of heart return decreased significantly in the early stage of sepsis induced by CLP. LVEDV reduced by 46%. Notable compensatory responses of the hearts in septic mice were observed, especially the systolic functions, in which LVEF and LVFS increased by 27% and 39%, respectively. However, the compensatory responses of diastolic function were weaker than the systoles. E/A ratio and EDT decreased by 30% and 25% respectively at the time point of 24 h. CONCLUSION: The strong compensatory cardiac functions are one of the factors for supporting the septic animal to survive. Protection of the cardiac functions especially the diastoles is important in the treatment of septic patients.