基于单导脑电的数字化新生儿脑功能监护仪的研制

Development of digitalized neonatal cerebral function monitor based on single-lead electroencephalography signal

目的新生儿脑功能监护仪大多基于单导脑电设计以适于长时监测。现有的新生儿脑功能监护仪多通过模拟电路以获取振幅整合脑电图(amplitude-integrated EEG,aEEG),其体积庞大,价格昂贵,缺少自动分析,在国内应用较少。为降低成本及提高便携性,本文设计了数字化新生儿脑功能监护仪。方法设计包含电极-头皮阻抗检测模块的前置脑电放大电路以采集单导脑电信号,利用基于OMAP-L137的双处理器嵌入式开发板实时计算和显示单导脑电的线性指标aEEG和非线性指标样本熵(sample entropy,SampEn),并设计实现用户界面控制和病案数据管理。结果本文设计的监护仪能够实时监控新生儿单导脑电的线性指标aEEG和非线性指标SampEn,实现对新生儿脑功能发育及脑损伤的客观、量化的评价。结论该监护仪提取的aEEG与现有设备具有较好的一致性,脑电的SampEn为新生儿脑功能判定提供了新的可靠判据,能够更全面地反映新生儿脑功能状况。

Objective Most of neonatal cerebral function monitors are designed based on single-lead electroencephalography （EEG） for long-time monitoring. The existing neonatal cerebral function monitors acquire the amplitude-integrated EEG （aEEG） with analog circuits, which are heavy, expensive, and seldom used in China. To improve the portability and reduce the cost of the instrument, a digitalized neonatal cerebral function monitor is developed. Methods The single-lead EEG was acquired by an EEG amplifier module with impedance detecting function. An embedded system based on dual-core embedded processer OMAP-L137 was designed to carry out the real-time computation and display of aEEG and sample entropy （SampEn） , to realize the user interface control and patient information management. Results This neonatal cerebral function monitor detected aEEG and SampEn simultaneously, and then provided an objective and quantitative evaluation on neonatal cerebral function. Conclusions The aEEG acquired by the digitalized neonatal cerebral function monitor is in accord with the results of existing equipments. SampEn is a new and reliable criterion of EEG and the monitor presents neonatal cerebral function more comprehensively.