低速弹颅脑伤后脑微循环变化的实验研究

Changes of cerebral microcirculation after craniocerebral missile wound (low velocity)

目的 研究猫在低速弹颅脑伤 (CMW )后脑微循环的改变 ,为临床治疗提供实验依据。 方法 改良Carey法制作低速弹猫CMW模型 ,观测伤前、伤后不同时间点软脑膜细动脉管径 (Da)、细静脉管径 (Dv)、脑皮层微区血流量 (CBF)、血压、脉搏、呼吸和采静脉血测算 ηb、ηp、PFC、HCT、ESR、AI、TK等血液流变学指标。 结果 全部动物生命体征稳定 ,无死亡。CMW后Da、Dv收缩持续 30min ,随之Da、Dv扩张 ,至 2h恢复正常 ;5～ 8h细动脉痉挛 ,而细静脉出现瘀血性扩张 ;微区CBF呈缺血 (0～ 30min)、充血 (1～ 1.5h)和瘀血 (5～ 8h) 3个时相的变化 ;致伤后 ,ηb、ηp、PFC、HCT、AI均较伤前明显升高 ,红细胞变形能力下降 ,至伤后 8h仍未恢复正常。 结论 低速弹致颅脑伤后 ,脑微循环发生了严重变化 ,至 8h仍不正常 ,进行相关治疗可望改善。

Objective [WT5”BZ]To seek the changes of cerebral microcirculation following a craniocerebral misile wound (CMW) (low velocity) in cats and to provide evidence for clinical treatment. [WT5”HZ]Methods [WT5”BZ]CMW animal model in cat was constructed by Carey method. Then, arteriole and venule caliber of pia mater, microregional cerebral blood flow (CBF) of brain, mean artery blood pressure (MABP), heart rate (HR), respiratory rate (RR) were monitored simultaneously at different time before and after wound. Blood samples were collected for surveying and calculating blood rheological idexes of blood viscosity (ηb), plasma viscosity (ηp), plasma fibrinogen concentration (PFC), hematocrit (HCT), erythrocyte sedimentation rate (ESR), aggregation index (AI) and deformability of red blood cells (RBC) (TK). [WT5”HZ]Results [WT5”BZ]Vital signs were kept stable at each time point without any death. Pial aterioles and venules kept a contraction for about 30 minutes after CMW. Then, they were dilated and recovered to normal after 2 hours. Arteriole spasm occurred from 5-8 hours and venule dilated on the contrary. CBF manifested ischemia, hyperemia and stagnation which appeared from 0-30 minutes, 1- 1.5 hours and 5-8 hours respectively. After CMW, blood rheological parameters including ηb,ηp, ESR, HCT, PFC and AI were increased significantly, the deformability of RBC decreased significantly and did not return to normal 8 hours later. [WT5”HZ]Conclusions [WT5”BZ] After CMW, cerebral microcirculation changes a lot and does not recover from 8 hours. A corresponding treatment is necessary accordingly.