Wu B, Xie B, Xue Y, You G, Lu S, Liu X
Institute of Space Medico-Engineering, Beijing, China.
Space Med Med Eng (Beijing). 1997 Aug;10(4):245-9.
The purpose of this study was to observe and analyse the changes of regional cerebral oxygen saturation (SrO2) under lower body negative pressure (LBNP). 12 healthy young subjects were tested in an LBNP chamber in sitting position. Incremental negative pressure was used and end points of test were onset of presyncopal symptoms or completion of the 15min test. The results were: (1) SrO2 showed a significant decrease under LBNP; (2) The magnitude of decrease of SaO2 showed significant differences among subjects with different reactions at the termination of LBNP; (3) Under LBNP the arterial oxygen saturation (SrO2) kept constant. The changes of SrO2 correlated strongly with the percentage changes of superaorbitalis arterial blood flow (r = 0.59-0.86, P < 0.05 or 0.01). It was suggested that the changes of SrO2 were related to the decrease of cerebral blood flow under LBNP. It was possible to use SrO2 to detect presyncopal and syncopal symptoms. So the monitoring of SrO2 could be used in studies of G-LOC.
本研究的目的是观察和分析下体负压（LBNP）下局部脑氧饱和度（SrO2）的变化。12名健康青年受试者在LBNP舱内坐位进行测试。采用递增负压，测试终点为晕厥前症状发作或15分钟测试结束。结果显示：（1）LBNP下SrO2显著下降；（2）LBNP结束时不同反应受试者的SaO2下降幅度存在显著差异；（3）LBNP下动脉血氧饱和度（SrO2）保持恒定。SrO2的变化与眶上动脉血流百分比变化密切相关（r = 0.59 - 0.86，P < 0.05或0.01）。提示SrO2的变化与LBNP下脑血流量减少有关。利用SrO2检测晕厥前和晕厥症状是可行的。因此，SrO2监测可用于G-LOC研究。
