人脑血氧的数据分析及其临床验证

Signals Analysis and Clinical Validation of Blood and Oxygen Data in Human Brain

本文采用自制的近红外双波长脑血氧监测仪对20例正常人、30例手术麻醉病人和30例心功能不全病人进行了脑血氧监测,应用功率谱和互相关函数的方法对采集的血和氧数据进行了分析,实验结果表明:(1)正常人及麻醉后病人脑血氧饱和度的值为80%左右,符合正常生理参数,心功能不全患者脑血氧饱和度平均值为72.8%,明显低于正常人及麻醉后病人,医学统计学分析P<0.01。(2)正常人及麻醉后病人脑血、氧波形信号显示血、氧波形中波峰、波谷对应良好;波形频率和节律稳定,而心功能不全患者脑血、氧波形信号表现为波动的频率和节律均不规则,其血、氧波动信号之间的对应性差。这提示出近红外光在生物组织中传递时可带来较为直观的脑组织血、氧变化信息。(3)心功能不全患者的功率谱曲线主频峰不清晰、功率谱基底宽,有许多活跃的频峰,血、氧的功率谱曲线吻合性差,与正常人及麻醉后病人脑血、氧波形主频峰清晰、功率谱基底部绝少主频峰外的其它频峰功率谱图存在明显差异。(4)正常人及麻醉后病人血氧互相关函数系数为-0.9825±0.1027,接近-1;而心功能不全患者的血氧互相关函数系数仅为-0.8923±0.1035,与正常人及麻醉后病人存在显著差异,医学统计学分析P<0.01。临床试验表明,血氧波形、功率谱和互相关函数对于分析人脑血、氧生理参数状况及其变化有一定的效果。

With a self-made near-infrared analytical instrument to blood and oxygen parameters in human brain,80 cases in which 20 were healthy and 30 were anaesthetised and others were patients with heart function lack were taken to examine,and the data of blood and oxygen in brain tissue were collected and analyzed by the method of power spectrum and correlation function.The results indicated that：（1） The average brain oxygen saturation of healthy cases and anaesthetised cases was about 80%,in accordance with normal parameter of physiology.Contrastively,the average brain oxygen saturation of patients with heart function lack was 72.8%,which was obviously less than that of healthy cases and anaesthetised cases.The probability of medical statistics was less than 0.01.（2） The shapes of wave of brain blood and oxygen for the healthy and the anaesthetised case revealed that small that periodical fluctuations with stable shape and base line,and the trend of increase or decrease of blood and oxygen parameters in brain tissue was synchronous and a phase reversal,but for the patients with heart function lack in a brain oxygen lack state,the shapes of wave were irregular.This was a hint that near infrared light passing through tissue can reflect the intuitionistic change of brain blood and oxygen parameters.（3） The power spectra of brain blood and oxygen for the healthy and the anaesthetised case had a clear main peak,narrow bandwidth and perfect superposition each other,but the power spectra for the patient with heart function lack in a brain oxygen lack state was on the contrary.（4） The average cross correlation coefficient of brain blood and oxygen for healthy and anaesthetised cases was-0.9825±0.1027 close to-1.But the average cross correlation coefficient for patients with heart function lack in a brain oxygen lack state was merely-0.8923±0.1035 which was obviously greater than-1 and the probability of medical statistics was less than 0.01.The clinic experiments proved that the shapes of waves,the power spectrum and cross correlation coefficient of brain blood and oxygen were useful to analyze the physiological status and changes of blood and oxygen in human brain.