冷却对振动引起的人手指感觉神经动作电位波幅的影响

Effects of cooling on the amplitude of vibration-induced sensory nerve action potentials

目的:观察冷却对振动引起的人手指感觉神经动作电位(SNAP)波幅的影响。方法:采用自身配对设计,随机选取15名健康成年人,利用冰袋将中指皮肤温度冷却至22℃左右,或保持常温(中指皮肤温度32℃左右),将振动器置于受试者中指掌指关节处,施加振动,振动幅度2 mm,频率60 Hz。分别于振动前、振动时、振动停止后,采用电生理感觉神经传导检查记录受试者中指SNAP的波幅。结果:相同温度条件下,振动时的中指SNAP波幅均较振动前低( P<0.05),在振动停止后即刻恢复至振动前水平,振动前与振动停止后中指SNAP波幅比较,差异无统计学意义( P>0.05)。与32℃条件下同振动时间点比较,受试者在22℃条件下的中指SNAP波幅较高( P<0.05)。受试者32℃条件下的中指SNAP波幅差为(61.7±15.1)%,22℃条件下的波幅差为(24.1±7.0)%,与32℃条件下相比,受试者22℃条件下的中指SNAP波幅差值较小( P<0.05)。 结论:冷却能显著减少振动对人手指SNAP波幅降低的影响,这可能是冷却疗法治疗手-臂振动综合征的潜在机制之一。

Objective To observe any effect of cooling on the amplitude of vibration-induced sensory nerve action potentials(SNAPs)in human digits.Methods The middle fingers of 15 healthy adults were either coled to about 22℃using an ice pack or kept at about 32℃.A vibrator was applied to the joint connecting the middle finger and the palm vibrating with an amplitude of 2mm at a frequency of 60Hz.The amplitudes of middle finger SNAPs be-fore,during and right after the vibration were recorded.Results The SNAP amplitude at a given temperature was lower during vibration than before it,but it immediately returned to the pre-vibration level after the vibration ceased.The middle finger SNAP amplitudes at 22℃were significantly higher than those at 32℃throughout.The decrease in amplitude at 32℃(61.7±15.1%)was significantly greater than that at 22℃(24.1±7.0%).Conclusions Cooling significantly reduces the effect of vibration on the amplitude of digital SNAPs.That suggests a way to protect the sen-sory nerves in hand-arm vibration syndrome.