微循环成像系统对脓毒症大鼠脑微循环监测的研究

Investigation of cerebral microcirculation in a rat sepsis model by microcirculation imaging system

目的:使用旁流暗视野成像设备监测脓毒症大鼠脑微循环的变化。方法:16只雄性SD大鼠行开颅手术,暴露脑皮层表面行微循环监测,随机分为脓毒症组(n=10)和假手术组(n=6),脓毒症组大鼠开腹后行盲肠结扎穿孔制作脓毒症模型,假手术组大鼠行开腹手术但不予盲肠结扎穿孔,利用旁流暗视野成像设备监测两组动物腹部术后基线、2h、4h及6h的灌注血管密度(PVD)、微血管血流指数(MFI),并记录对应时间点的平均动脉血压(MAP)。结果:假手术组MFI、PVD和MAP随时间变化均差异无统计学意义(P>0.05),脓毒症组MFI、PVD在基线、2h的改变差异无统计学意义(P>0.05),在4h、6h出现下降(P<0.05),MAP在基线、2h、4h改变差异无统计学意义(P>0.05),在6h时出现下降(P<0.05)。结论:在盲肠结扎穿孔诱导的脓毒症大鼠模型中,脑微循环在脓毒症早期即发生改变,并且随着脓毒症进展而恶化。

Objective:To investigate the cerebral microcirculation in a rat sepsis model through sidestream dark field(SDF)imaging microscope.Method:Sixteen rats were prepared with craniotomy to expose the surface of cortex for microcirculation observation.Then randomized the rats into a sepsis group(n=10)and a sham group(n=6),the rats in sepsis group went through abdominal surgery with cecum ligation and puncture(CLP)to induced sepsis,and the rats from sham group did not take the CLP procedure,just had laparotomy.Perfused vessel density(PVD)and microvascular flow index(MFI)were calculated through SDF imaging microscope at baseline,2,4,and 6 hours after the operation.Mean arterial pressure was also recorded at the same time points.Result:Comparing with the baseline,there was no statistical difference of MFI at 2 h,4 hor 6 hin the sham group(P>0.05),either with PVD or MAP.In the sepsis group,MFI and PVD were significantly reduced at 4 hand 6 h(P<0.05),and MAP was reduced at 6 h(P<0.05).Conclusion:Cerebral microcirculation alteration can be observed at early stage of sepsis in a rat sepsis model induced by CLP,and it would deteriorate with the sepsis developing.