利多卡因对小血管直径的影响

目的：利多卡因局部应用以解除血管痉挛。但对于其周围血管活性作用究竟是使血管扩张还是收缩，尚存在明显分歧。方法：采用展开的大白鼠睾提肌膜型，在显微镜下活体观察用肾上腺素致痉的小血管对２％、５％、１０％、２０％和２５％浓度的利多卡因局部滴注的反应，以及未致痉的小血管对２％利多卡因的反应。结果：不同浓度的利多卡因对痉挛的小动脉均有短暂的扩张作用，但１分钟后，动脉直径又开始回缩；１０分钟时，２％和５％利多卡因进一步加重了痉挛，其它浓度的利多卡因也未能解除痉挛。静脉对不同浓度的利多卡因均无明显反应。未致痉的小动脉对２％利多卡因亦呈强烈收缩反应。结论：不宜用利多卡因局部滴注以求解除血管痉挛。

EFFECTS OF LIDOCAINE ON DIAMETER OF SMALL BLOOD VESSELS

Objective:Lidocaine was widely used topically as a spasmolytic agent.But whether its peripheral blood vessel action is dilatation or constriction remains in controversy,Methods:A microscopic observation was made in an in vivo open rat cremaster muscle preparation to determine the response of adrenaline pre-constricted small blood vessels to the topical application of lidocaine in 2%,5%,10%,20%,and 25%concentrations respectively,and the response of unpre-constricted small vessels to 2%lidocaine solution.Results:The lidocaine solutions in various concentrations all resulted in a transient dilatation of small arteries,But after 1 minute,the arteries constricted again.At the end of 10 minutes duration,the 2%and 5%solutions intensified the spasm,and the rest concentration solutions also did not produce relief of spasm.The small veins showed no statistically significant response to the various concentration solutions of lidocaine,The unpre-constricted small arteries constricted apparently to the topical application of 2%lidocaine.Conclusions: Relief of vasospasm using topical lidocaine should be avoided.