术中脊髓监护体感诱发电位异常预警动态预测模型研究

发布时间：2018-05-17 23:27

本文选题：术中监护 + 体感诱发电位　；参考：《北京协和医学院》2015年博士论文

【摘要】：在脊柱外科手术中,体感诱发电位可以减低手术风险,已广泛应用于术中脊髓功能监护,是近年来脊髓监护中最常应用的电生理技术。然而,由于多重因素的影响,术中体感诱发电位存在着变异性；另外,体感诱发电位受各种噪声的干扰,信噪比非常低,使得诱发脑电的识别和特征提取比较困难。因此,体感诱发电位的检测以及术中体感诱发电位变异性一直是临床监护中非常困难的一个问题。本文针对术中体感诱发电位变异性影响因素的多样性及各因素之间错综复杂的联系,利用灰色理论对影响体感诱发电位变异性的主要非手术因素进行多因素分析；针对体感诱发电位的信噪比低的特性以及术中监护实时性的要求,将限制性二阶盲源分离算法应用于体感诱发电位信噪比的提高；在此基础上,利用支持向量回归的非线性特征,提出了体感诱发电位异常动态预警模型,提高了术中监护的可靠性。主要研究内容和结论如下：(1)系统地分析人体测量学指标和人体生理参数对术中体感诱发电位的影响。首先,运用统计分析方法分析了各阶段SEP波峰潜伏期和波幅的变化率与身高、体质量、年龄的相关性,结果显示SEP的变化和身高、体质量、年龄这些人体测量学指标没有显著关系,如果体感诱发电位发生变化,不需要再考虑病人的体质量、身高、年龄带来的影响,这对脊髓侧凸矫形手术术中诱发电位监护的正确操作具有重要的指导意义；运用灰色关联度分析了矫形手术过程中SEP波峰潜伏期和波幅的变化率与五个生理因素(重点考虑非手术因素包括血压、心律、体温、动脉二氧化碳分压、麻醉等对术中SEP变化的影响)变化率的相关程度,结果显示各生理参数的变化对SEP有不同程度的影响,提示术中应监测术中SEP波形及各生理参数的变化,排除术中生理参数变化造成的监护误诊,提高了术中监护可靠性。(2)通过建立大鼠脊髓损伤模型,评价限制性二阶盲辨识快速提取方法的性能。针对体感诱发电位的特征对传统二阶盲辨识算法进行改进,并利用重物下降大鼠脊髓损伤模型模拟脊髓挫伤,验证新算法对脊髓损伤的判别能力,将处理结果与传统平均叠加处理结果比较得出,限制性二阶盲辨识方法可以提取出清晰的单次SEP信号波形,能够很好地测量信号的潜伏期和幅值,与传统平均叠加方法相比,提取体感诱发电位的效果更好,提取的诱发电位潜伏期和幅值对脊髓损伤的响应比平均叠加方法更快更显著,不仅降低了提取时间,还将有助于为脊髓损伤早期预警提供更多信息。(3)建立体感诱发电位异常动态预警模型。综合考虑影响术中体感诱发电位变化的非手术因素,利用支持向量回归的非线性特征,建立术中体感诱发电位动态预测模型,对监护基线进行动态调整,并给出一定置信度下的置信区间。体感诱发电位动态预测模型很好的拟合出了体感诱发电位的潜伏期和峰值,预测趋势线与实际观测值基本一致,在可接受的误差范围内得到了比较满意的预测结果,在99%置信水平下,大部分实际观察值都落在预测区域范围内。这不仅增加了术中监护的可靠性,而且降低了由于非手术因素带来的监护误差。针对影响术中体感诱发电位监护可靠性的关键问题,本研究系统分析影响术中体感诱发电位的非手术因素,重点探讨了主要因素与术中体感诱发电位变异性的关系,并通过动物实验验证了体感诱发电位单次提取技术对脊髓损伤的动态跟踪能力,综合考虑影响术中体感诱发电位变异性的非手术因素以及动态监护的必要性,建立了体感诱发电位异常动态预警模型。本课题的研究能够提高术中体感诱发电位监护的可靠性,如果本研究成果应用于临床监护,可以随时了解脊髓功能状态,及早发现神经功能损伤并确定损伤部位及其诱因,及时采取措施纠正不正当的手术操作,降低病人痛苦,将会使损伤得以恢复或者使损伤达到最低限度,避免出现不可逆的神经功能损害；同时,由于有效避免了脊髓功能损伤,使得治疗、护理、康复费用有所降低,减轻了患者的费用负担。
[Abstract]:In spinal surgery, somatosensory evoked potential can reduce the risk of operation and has been widely used in the intraoperative monitoring of spinal cord function. It is the most commonly used electrophysiological technique in spinal cord monitoring in recent years. However, due to the influence of multiple factors, the somatosensory evoked potential exists variability in the operation, and the somatosensory evoked potential is disturbed by various noises. Therefore, the detection of somatosensory evoked potential and the variability of somatosensory evoked potential in the operation have been a very difficult problem in clinical monitoring. The diversity of factors affecting the variability of somatosensory evoked potential in the operation and the complexity of the factors are complicated in this paper. The main non operative factors that affect the somatosensory evoked potential variability are analyzed by the grey theory. In view of the low signal-to-noise ratio of somatosensory evoked potential and the requirement of real-time monitoring in the operation, the restrictive two order blind source separation algorithm is applied to the enhancement of the signal to noise ratio of the somatic induced generation potential. On this basis, Using the nonlinear characteristics of support vector regression, an abnormal dynamic early-warning model of somatosensory evoked potential is proposed, which improves the reliability of intraoperative monitoring. The main contents and conclusions are as follows: (1) systematic analysis of the effects of anthropometric parameters and human physiological parameters on the somatosensory evoked potential in the operation. First, the statistical analysis method is used. The correlation between the variation of SEP wave peak latency and wave amplitude with height, body mass and age showed that there was no significant relationship between SEP and height, body mass and age. If somatosensory evoked potential was changed, the effects of body mass, height and age, this pair of ridges were not needed. The correct operation of evoked potential monitoring in the operation of scoliosis orthopedics has important guiding significance. Using grey correlation analysis, the changes of SEP wave peak latency and amplitude in orthopedic surgery and five physiological factors (focusing on non operative factors including blood pressure, heart rhythm, body temperature, arterial carbon dioxide partial pressure, anesthesia, etc.) are used in the operation. The effect of the change of SEP) the correlation of the change rate, the results showed that the changes of the physiological parameters had different influence on the SEP. It was suggested that the changes of the SEP waveform and the physiological parameters should be monitored during the operation, the monitoring misdiagnosis caused by the changes of physiological parameters during the operation and the reliability of the intraoperative monitoring should be eliminated. (2) the model of spinal cord injury was established by establishing the rat spinal cord injury model, Evaluate the performance of the limited two order blind identification fast extraction method. According to the characteristics of the somatosensory evoked potential, the traditional two order blind identification algorithm is improved, and the spinal cord contusion is simulated by the model of the spinal cord injury of the weight loss rat, and the discriminant ability of the new algorithm for spinal cord injury is verified. The results are compared with the traditional average superposition treatment results. It is concluded that the restricted two order blind identification method can extract a clear single SEP signal waveform, and can measure the latency and amplitude of the signal very well. Compared with the traditional average superposition method, the effect of extracting the somatosensory evoked potential is better. The evoked potential latency and amplitude response to the spinal cord injury is faster and more faster than the average superposition method. Significantly, it not only reduces the time of extraction, but also helps to provide more information for early warning of spinal cord injury. (3) establish an abnormal dynamic early warning model of somatosensory evoked potential. Take into account the non operative factors that affect the changes of somatosensory evoked potential in the operation, and use the non linear characteristics of support vector regression to establish the dynamic preconditioning potential of the somatosensory evoked potential in the operation. The model is used to dynamically adjust the monitoring baseline and give confidence interval under certain confidence. The dynamic prediction model of somatosensory evoked potential can fit the latent period and peak of somatosensory evoked potential well, and the forecast trend line is basically consistent with the actual observation value, and a satisfactory prediction result is obtained within the acceptable error range. At the 99% confidence level, most of the actual observation values fall within the range of the prediction area. This not only increases the reliability of the intraoperative monitoring, but also reduces the monitoring error caused by the non operative factors. This study systematically analyzes the effect of the somatosensory evoked potential in the operation for the key problems affecting the monitoring reliability of the somatosensory evoked potential during the operation. The relationship between the main factors and the variability of somatosensory evoked potential was emphatically discussed, and the dynamic tracking ability of the single extraction technique of somatosensory evoked potential for spinal cord injury was verified by animal experiments, and the non operative factors affecting the variability of somatosensory evoked potential in the operation and the necessity of dynamic monitoring were considered. An abnormal dynamic early warning model of somatosensory evoked potential can be used to improve the reliability of the monitoring of somatosensory evoked potential in the operation. If the results of this study are applied to clinical monitoring, the functional state of the spinal cord can be understood at any time, the damage of the nerve function can be found early and the location and cause of the injury can be determined, and the measures to correct the dishonesty in time should be taken. Operation, reducing the patient's pain, will make the injury recover or minimize the damage and avoid irreversible nerve function damage. At the same time, the cost of treatment, nursing and rehabilitation will be reduced and the cost burden of the patient is reduced because of the effective avoidance of spinal cord injury.
【学位授予单位】：北京协和医学院
【学位级别】：博士
【学位授予年份】：2015
【分类号】：R687.3

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