Study of Electromagnetic Interference with Medical Engineering Equipment

医疗工程设备电磁干扰研究

基本信息

批准号：
04557118
负责人：
KISHIMOTO Seiichi
金额：
$ 3.07万
依托单位：
Kochi National College of Technology
依托单位国家：
日本
项目类别：
Grant-in-Aid for Developmental Scientific Research (B)
财政年份：
1992
资助国家：
日本
起止时间：
1992 至 1994
项目状态：
已结题

项目摘要

We had studied the Electromagnetic Interference (EMI) with the electrocardiograph (ECG) in case of using an electric scalpel, which is a recent problem in medical operation rooms and is a current issue Japanese Association for Operating Room Technology. We pointed out that the noise induced on the AC-line and the noise radiated from an electric scalpel to ECG can be measured by spectrum analyzer or oscilloscope. As a result, it proved that EMI occurs in a wide frequency range on the ECG electrode cord while an electric scalpel is being operated. And EMI on the ECG proved to be induced through the ECG electrode cord. The noise induced on the ECG electrode cord indicates a special performance curve in case of operation both for cutting and for coagulation. Therefore, we made a proposal for the way of suppressing EMI on the ECG.It is that a low-pass filter is added between the ECG electrode code and the ECG transmitter. We have noticed that the origin of EMI's noise on the ECG occurs in a much lower frequency than 1kHz. We inspected these articles and the characteristic- of electric performance curves which were determined to 1kHz for the cut-off frequency. We suggest an added filter's circuit which accommodates a clamp circuit and a limited circuit. Furthermore, the cut-off frequency should be given at the lower frequency from 200Hz through 1kHz, because the spectrum of physical signals of ECG is even lower than about 30Hz except DC.Therefore, they are much smaller than EMI level occurring at the same frequency. As a result, we proposed DSP filter, which has the real-time operation.

我们研究了使用电手术刀时心电图仪 (ECG) 的电磁干扰 (EMI)，这是医疗手术室中最近出现的问题，也是日本手术室技术协会的最新问题。我们指出，交流线上感应的噪声和电手术刀辐射到心电图的噪声可以通过频谱分析仪或示波器来测量。结果证明，在操作电手术刀时，心电图电极线上会在很宽的频率范围内产生 EMI。 ECG 上的 EMI 被证明是通过 ECG 电极线感应的。 ECG 电极线上感应的噪声表明在切割和凝固操作情况下的特殊性能曲线。因此，我们提出了抑制心电图EMI的方法，即在心电电极码和心电发射器之间添加低通滤波器。我们注意到 ECG 上 EMI 噪声的起源发生在比 1kHz 低得多的频率中。我们检查了这些制品和确定截止频率为 1kHz 的电性能曲线的特性。我们建议添加一个滤波器电路，其中包含钳位电路和限制电路。此外，截止频率应给出在 200Hz 至 1kHz 的较低频率，因为心电图物理信号的频谱甚至低于除 DC 之外的 30Hz 左右。因此，它们远小于相同频率下出现的 EMI 水平。为此，我们提出了具有实时运算功能的DSP滤波器。