Di Massa A, Orlandini N, Di Don Francesco P, Simone M E
Dipartimento Scienze Odontostomatologiche, Università degli Studi, Siena.
Minerva Anestesiol. 1997 Oct;63(10):315-9.
The practice of local anaesthesia aided by ENS, among other things, is based on the use of available electric signals searching peripheral nerves. Most electric generators produce a square monopolar signal that is potentially dangerous because it exists a risk of hyperpolarization damage with neural lesions by galvanic effect.
To inform about the use of a bipolar signal, different than the usual square monophasic signal. In theory a bipolar signal prevents the risk of hyperpolarization by lessening average intensity of current crossing the tissues.
Our experience is based on 70 clinical cases of bi-block performed by searching the nerve by using an electric bipolar signal to locate a peripheral nerve.
Local anaesthesia can be successfully performed by using bipolar electric signals not currently employed. In 2/70 patients it was needed to perform surgery under general anesthesia. The rate of successful blocks was similar to the results of current literature.
Most authors search peripheral nerves by square monophasic signals. It arrives because it's widely believed that a square signal is advantageous because of high ratio di/dt (intensity/time). Today, it's not assessed in clinical practice that an electric signal is deeply modified in its parameters and its form by capacitive and resistive properties of the human body.
在其他方面，借助电刺激神经定位（ENS）进行局部麻醉的操作是基于利用可用的电信号来寻找周围神经。大多数发电机产生方形单极信号，这具有潜在危险性，因为存在因电效应导致神经损伤而出现超极化损伤的风险。
介绍一种与通常的方形单相信号不同的双极信号的使用情况。理论上，双极信号通过降低穿过组织的电流平均强度来防止超极化风险。
我们的经验基于70例通过使用双极电信号寻找神经来进行双阻滞的临床病例。
使用目前未使用的双极电信号可以成功实施局部麻醉。70例患者中有2例需要在全身麻醉下进行手术。成功阻滞率与当前文献结果相似。
大多数作者通过方形单相信号来寻找周围神经。这是因为人们普遍认为方形信号由于高的di/dt（强度/时间）比而具有优势。如今，在临床实践中尚未评估人体的电容性和电阻性特性会使电信号的参数和形式发生深刻改变。
