Study on noninvasive and continuaous monitoring of myocardial oxygen metabolism by NIRS

NIRS无创连续监测心肌氧代谢的研究

• 批准号: 05557070
• 负责人: ODA Toshiyuki
• 金额: $ 5.44万
• 依托单位: Kagoshima University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Developmental Scientific Research (B)
• 财政年份: 1993
• 资助国家: 日本
• 起止时间: 1993 至 1994
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-05557070/
• 关键词: Myocardial oxygen metabolism; Near-infrared spectrophotometry; Transesophageal analysis

We examined the possiblity of the measurements of myocardial oxygen status by near-infrared spectrophotometry (NIRS) in beating heart in three series of experiments.Experiment (1) : analysis of hemoglobin (Hb) , myoglobin (Mb) and cytochrome oxidase (Cyt.aa3) in the myocardium.The experiments were performed in isolated perfused rat heart for in situ measurement of Hb, Mb and Cyt.aa3. As a result, we established the following equations.[Hb] =5.12xA_<700>-13.99x_<730>+8.45x_<750>[Mb] =-2.85x_<700>+9.94x_<730>-6.44x_<750>[HbO2+MbO2] =-4.97x_<700>+7.99x_<730>-2.08x_<750>[Cyt.aa3] =_<805>- (-2.69x_<700>+3.93x_<730>-0.08x_<750>)Experiment (II) : in vivo measurements of Hb, Mb and Cyt.aa3 in the rat.The measurements were performed in exposed heart and through the chest wall during normoxic and hypoxic conditions. Following reduction of inspired oxygen concentration, it was shown that propotinal deoxygenation of Hb with FIO2, that the reduction of Mb for FIO2 at 0.12, and that the reduction of cyt.aa3 at 0.08 indicating successful measurements of myocardial oxygen metabolism by our equations.Experiment (III) : transesophageal measurements of myocardial Hb, Mb and Cyt, aa3 in the pig.The measurements were performed through esophagus. The signals of myocardial Hb+Mb or Cyt.aa3 were able to detect showing the reduction of Hb, Mb and during hypoxic hypoxia, however, we so far could not completely eliminate the contaminated signals from esophageal muscle.We conclude that we can measure the myocardial oxygen status by near-infrared spectrophotometry in beating heart, and that transesophageal measurement could be possible indicating wide applicability in clinical practice.

本实验通过三个系列的实验研究了近红外分光光度法（NIRS）测定心脏跳动时心肌氧状态的可能性：实验（1）：心肌血红蛋白（Hb）、肌红蛋白（Mb）和细胞色素氧化酶（Cyt.aa3）的分析。因此，我们建立了以下方程。[Hb]=5.12xA_<700>-13.99x_<730>+8.45x_<750>[Mb] =-2.85x_<700>+9.94x_<730>-6.44x_<750>[HbO2+MbO2] =-4.97x_<700>+7.99x_<730>-2.08x_<750>[Cyt.aa3] =_<805>-（-2.69x_<700>+3.93x_<730>-0.08x_<750>）实验（II）：在大鼠中Hb、Mb和Cyt.aa3的体内测量。在常氧和缺氧条件下，在暴露的心脏中和通过胸壁进行测量。随着吸入氧浓度的降低，表明Hb与FIO 2的比例性脱氧，FIO 2的Mb降低为0.12，cyt. aa 3降低为0.08，表明通过我们的方程成功测量了心肌氧代谢。经食管测定猪心肌Hb、Mb和Cyt、aa 3。心肌Hb+Mb或Cyt.aa3信号能检测到缺氧时Hb、Mb和的减少，但目前还不能完全消除食管肌的污染信号，因此，近红外分光光度法可以在心脏跳动中检测心肌氧状态，经食管测量具有广泛的临床应用价值。