摘要
目的:以临界关闭压无创测定健康志愿者的脑血流调节下限,探讨CO2变化过程中脑血流自动调节功能的变化规律。方法:实验于2003-08/2004-08在广州医学院第二附属医院神经内科和中山大学附属第一医院神经科进行。同步监测79名正常健康志愿者(均同意参加实验)在正常呼吸、屏气和过度换气时的大脑中动脉血流、桡动脉血压和呼气终末呼出气体CO2分压,并离线计算临界关闭压和脑血流自动调节下限。结果:按意向处理分析,79名被试者全部进入结果分析。①脑血流自动调节下限:屏气时明显高于正常呼吸时犤(69.4±15.0),(58.4±10.4)mmHg,P<005犦,过度换气时明显下降犤(44.0±10.8)mmHg,P<0.05犦。②临界关闭压:屏气时较正常呼吸时显著下降犤(27.7±17.2),(31.2±12.5)mmHg,P<0.05犦,过度换气时明显升高犤(39.0±11.8)mmHg,P<0.05犦。③呼气终末呼出气体CO2分压:过度换气时较正常呼吸明显下降犤(32.0±6.4),(46.2±5.4)mmHg,P<005犦。④相关性分析:三种情况下的脑血流自动调节下限均与临界关闭压负相关(r=-0.4189,-0.4870,-0.4661,P<0.05),屏气和过度换气时脑血流自动调节下限的变化率也与临界关闭压的变化率呈负相关(r=-0.6105,-0.5551,P<0.05),且低CO2时脑血流自动调节下限的变化率和呼气终末呼出气体CO2分压的变化率呈“S”型曲线关系。结论:屏气CO2上升时脑血流自动调节下限上移,过度换气CO2下降时脑血流自动调节下限下移,其机制和脑血管平滑肌收缩程度的改变密切相关。
AIM： To estimate the Lower limit of cerebral autoregulation （LLCA） of healthy volunteer with non-invasive critical closing pressure, and investigate the change law of cerebral blood stream autoegulation function following end-tidal CO2. METHODS： The experiment was conducted in the Department of Neurology of Second Affiliated Hospital of Guangzhou Medical College and Department of Neurology of First Affiliated Hospital of Sun Yat-sen University from August 2003 to August 2004. Synchronization monitoring was performed, on normal healthy volunteer （all agreed to join the experiment） testing the cerebral blood flow of middle cerebral artery, radial blood pressure and end-tidal CO2 （ETco2） at normal breathing, breathholding and hyperventilation. The LLCA was determined by critical closing pressure （CCP）. RESULTS：According to intention-to-treat analysis, 79 quizzees were all in involved in the analysis of results. ① LLCA： it was significantly higher at breathholding than that at normal breathing [（69.4±15.0）, （58.4±10.4）mmHg,（P 〈 005）], and it siguificantly decreased at hyperventilation [（44.0±10.8）mmHg, （P 〈 0.05）]. ② CCP： it was significantly lower at breathholding than that at normal breathing [（27.7±17.2）, （31.2±12.5）mmHg, （P 〈 0.05）], and it significantly increased at hyperventilation [（39.0±11.8）mmHg,（P 〈 0.05）]. ③ ETco2： it significantly decreased at hyperventilation than that at normal breathing [（32.0±6.4）, （46.2±5.4）mmHg, P 〈 005]. ④ Correlation analysis： LLCA under the three condition had negative correlation with CCP （r=-0.4189, -0.4870, -0.4661, P 〈 0.05）. The change rate of LLCA at breathholding and hyperventilation also had negative correlation with the change rate of CCP （r=-0.6105, -0.5551, P 〈 0.05）, and the change rate of LLCA with low CO2 and the change rate of ETco2 presented “S” type curvilinear relationship. CONCLUSION： LLCA at the increase of breathholding CO2 is ascenda
出处
《中国临床康复》
CSCD
北大核心
2005年第25期73-75,共3页
Chinese Journal of Clinical Rehabilitation
基金
广州医学院博士启动基金资助(03-Q-01)~~
