摘要
目的:研制一种基于胸阻抗(transthoracic impedance,TTI)检测的电流自动调节型除颤仪,以实现对于高TTI患者能够输出恒定的电流,从而保证除颤效率。方法:该除颤仪主要由STM32F767主控芯片、TTI检测电路、高压充电电路、高压监测电路、放电电路和放电电流监测电路组成。软件采用C语言设计,以KeilμVision5 IDE为开发平台。将研制完成的样机作为实验机,临床使用的能量自动调节型除颤仪作为对照机,采用专业测试仪器对实验机进行TTI检测、高压监测、放电能量控制、放电电流监测等性能测试,通过模拟阻抗和动物实验分别对实验机和对照机的输出电流与除颤波形和除颤效率进行测试。采用SPSS 22.0软件进行统计学分析。结果:实验机对TTI检测、高压监测、放电能量控制和放电电流监测的测量误差分别为3.0%、2.7%、4.8%和4.3%。当负载阻抗>100Ω时,实验机输出的除颤电流显著高于对照机(P<0.01)。实验机在高阻抗水平输出的除颤波形脉冲宽度为6 ms,短于现有除颤仪(20 ms),除颤效果较好。动物实验表明,当放电能量<0.5 J或>1.0 J时,实验机的除颤成功率均高于对照机(P均<0.05)。当输出电流≥0.9 A时,实验机的除颤成功率显著高于对照机(P<0.05)。结论:基于TTI检测的电流自动调节型除颤仪可以显著提高对高TTI实验动物的除颤成功率,弥补了现有除颤仪对TTI较高时输出电流不足的问题。
Objective To develop a defibrillator with automatic current adjustment based on transthoracic impedance(TTI)detection to achieve a constant current output for patients with high TTI and thus ensure defibrillation efficiency.Methods The defibrillator mainly consisted of a STM32F767 microcontroller,a TTI detection circuit,a high voltage charging circuit,a high voltage monitoring circuit,a discharge circuit and a discharge current monitoring circuit.The software was designed in C language with KeilμVision5 IDE as the development platform.The completed prototype was used as the experimental machine and the clinically applied defibrillator with automatic energy adjustment was used as the control machine.The performance of the experimental machine in terms of TTI detection,high voltage monitoring,discharge energy control and discharge current monitoring were tested by professional test instruments.The output current,defibrillation waveform and defibrillation efficiency of the two defibrillators were measured by dummy load and animal experiments.Statistical analysis was executed with SPSS 22.0 software.Results The measurement errors for TTI detection,high voltage monitoring,discharge energy control and discharge current monitoring for the experimental machine were 3.0%,2.7%,4.8%and 4.3%respectively.The defibrillation current output of the experiment machine was significantly higher than that of the control machine when the load impedance was greater than 100Ω(P<0.01).The pulse width of the defibrillation waveform output at the high impedance level was 6 ms,which was shorter than that of the existing defibrillator(20 ms)and resulted in better defibrillation effect.Animal experiments showed that the defibrillation success rate of the experimental machine was higher than that of the control machine when the discharge energy was lower than 0.5 J or higher than 1.0 J(all P<0.05).When the output current was not lower than 0.9 A,the defibrillation success rate of the experimental machine was significantly higher than that of the control machine(P<0.05).Conclusion The defibrillator with automatic current adjustment based on TTI detection can significantly improve the success rate of defibrillation and compensate for the inadequate output current of existing defibrillators in high TTI.
作者
李伟明
谢佳玲
彭莉
魏良
鄢苏鹏
李永勤
LI Wei-ming;XIE Jia-ling;PENG Li;WEI Liang;YAN Su-peng;LI Yong-qin(Department of Biomedical Engineering and Imaging Medicine,Army Medical University,Chongqing 400038,China)
出处
《医疗卫生装备》
CAS
2021年第6期32-39,共8页
Chinese Medical Equipment Journal
基金
重庆市基础科学与前沿技术重点项目(cstc2017jcyjBX0053)。
关键词
胸阻抗
除颤仪
室颤
心脏骤停
电流自动调节
除颤
transthoracic impedance
defibrillator
ventricular fibrillation
cardiac arrest
automatic current adjustment
defibrillation
