受压迫神经内血流量变化的研究

Blood flow changes in compressed nerve

目的对在不同条件下受压迫神经内血流量的变化与神经电生理学变化间的关系进行研究，以期发现其内在联系及规律，为临床诊断和治疗提供依据。方法 30只大白兔随机分成六组，其中四组为对照组，两组为实验组。对照组 1:仅显露坐骨神经，分别测量近端、中点、远端三点的血流量，各点在 90 min内分别测量 10次。对照组 2:显露坐骨神经后，在其下放置一张纸片，其余操作同对照组 1。对照组 3:同对照组 2，于近端神经上放置刺激器但并不给予刺激，再测量血流量，方法同对照组 1。对照组 4:同对照组 3，但开始刺激，每刺激一次分别测量三点的血流量，重复 10次。实验组 1:于近端和中点间夹一个血管夹后，操作同对照组 4。实验组 2:于近端和中点间夹一个血管夹，再于中点和远端间夹一个血管夹后，操作同对照组 4。结果在 1， 2， 3， 4对照组分别发现单纯显露神经，放置纸片，放置刺激器和单纯刺激时近端、中点和远端三点的血流量是稳定的。在实验组 1用一个血管夹压迫神经，在压迫前、后近端和中点的血流量均有降低，而远端的血流量则基本不变。与此同时神经传导速度降低约 20％。在实验组 2，当双重压迫时，近端和中点的血流量亦有显著的降低，而神经传导速度减低 30％左右。结论通过本实验可见双重压迫组中?

Objective To study the difference between single and double site compressions on blood flow and nerve conduction velocity(NCV) in rabbits. Methods 30 rabbits (weighing 3～ 5 kg) were divided into 4 control and 2 experimental groups. The rabbits were anesthetized and the sciatic nerve was exposed. The vascular clamps were placed over the nerve, and the stimulating electrode was positioned on the nerve proximally to evoke motor activity. Electomyographic activity was recorded from gastrocnemius muscle. The Laser Doppler was used to monitor blood flow in proximal, middle and distal sites of the nerve. Results In single compressed group, before and after compression the blood flow in proximal and middle sites were decreased (P< 0.05), the NCV was decreased by 20％ . In double compressed group, blood flow also decreased, (in proximal site P< 0.05, in the middle site P< 0.01). The NCV was decreased by 30％ . Conclusion Low pressure, double site compression significantly reduces the nerve blood flow. This experiment supports Upton's Hypothesis on double crush syndrome.