Koura S S, Doppenberg E M, Marmarou A, Choi S, Young H F, Bullock R
Division of Neurosurgery, Medical College of Virginia, Virginia Commonwealth University, Richmond, USA.
Acta Neurochir Suppl. 1998;71:244-6. doi: 10.1007/978-3-7091-6475-4_70.
In previous studies, Katayama and our group have documented a massive increase in excitatory amino acid release following traumatic brain injury, in both rat fluid percussion, and humans [2,5]. To test the hypothesis that the magnitude of this "Excitotoxic Surge" plays a significant role in determining 6-month patient outcome. We have studied 83 consecutive severely head injured patients at the Medical College of Virginia for inclusion into this study. A microdialysis probe was placed within the cortex to continuously measure dialysate excitatory amino acids (Glutamate and Aspartate), along with several other analytes for approximately 5 days after injury. ICP, CPP, and MABP measurements were also time linked with each analyte measurement to create a neurochemical, clinical, and physiological "profile" for each patient. Outcome was determined by follow up using the Glasgow 6-Month outcome scale. A very strong correlation existed between the release of the EAA's glutamate and aspartate after TBI (p < 0.0001). Patients with significantly elevated mean glutamate values for the entire monitoring period were most likely to exhibit elevated levels of ICP. The magnitude of glutamate released significantly correlates with 6-month patient outcome (p = 0.0234). When patients were subdivided by the CT diagnosis of lesion type, we found that those patients with contusions displayed the highest overall of EAA's.
在先前的研究中，片山和我们的团队已经证明，在创伤性脑损伤后，无论是在大鼠液压冲击伤模型还是人类患者中，兴奋性氨基酸的释放都会大幅增加[2,5]。为了验证“兴奋性毒性激增”的程度在决定患者6个月预后方面起重要作用这一假设，我们在弗吉尼亚医学院对83例连续的重度颅脑损伤患者进行了研究，以纳入本研究。在损伤后约5天内，将微透析探针置于皮质内，以连续测量透析液中的兴奋性氨基酸（谷氨酸和天冬氨酸）以及其他几种分析物。颅内压（ICP）、脑灌注压（CPP）和平均动脉血压（MABP）的测量也与每次分析物测量时间相关联，以创建每个患者的神经化学、临床和生理“概况”。通过使用格拉斯哥6个月预后量表进行随访来确定预后。创伤性脑损伤后兴奋性氨基酸谷氨酸和天冬氨酸的释放之间存在非常强的相关性（p<0.0001）。在整个监测期内平均谷氨酸值显著升高的患者最有可能出现颅内压升高。谷氨酸释放的程度与患者6个月的预后显著相关（p = 0.0234）。当根据CT诊断的病变类型对患者进行细分时，我们发现那些有脑挫伤的患者兴奋性氨基酸的总体水平最高。
