Batzel Jerry Joseph, Goswami Nandu, Lackner Helmut Karl, Roessler Andreas, Bachar Mostafa, Kappel Franz, Hinghofer-Szalkay Helmut
Institute for Mathematics and Scientific Computing, University of Graz, Heinrichstrasse 36, 8010, Graz, Austria.
Cardiovasc Eng. 2009 Dec;9(4):134-43. doi: 10.1007/s10558-009-9086-z.
To investigate patterns of cardiovascular control, a protocol of head up tilt (HUT) followed by lower body negative pressure (LBNP), which represents a significant cardiovascular control challenge, was employed. Linear regression of beat-to-beat heart rate (HR) and mean blood pressure (MBP) data collected over repeated tests was used to analyze control response during the LBNP phase of the combined HUT + LBNP protocol. Four runs for each of 10 healthy young males reaching presyncope were analyzed. Subjects were classified into 2 groups based on the consistency of MBP regulation in response to central hypovolemia induced by LBNP. The consistent group tended to exhibit consistent HR slope (rate of change of HR over time as calculated by linear regression) whereas subjects in the inconsistent group could not be easily classified. Subjects with consistent MBP maintenance exhibited patterns suggesting a consistency of response in cardiovascular control whereas subjects less successful in maintaining MBP exhibited less clearly defined patterns over four runs.
为了研究心血管控制模式，采用了一种先进行头高位倾斜（HUT）然后进行下体负压（LBNP）的方案，下体负压是一项重大的心血管控制挑战。通过对重复测试中逐搏心率（HR）和平均血压（MBP）数据进行线性回归，来分析联合HUT + LBNP方案中LBNP阶段的控制反应。对10名达到前驱晕厥的健康年轻男性每人的4次测试进行了分析。根据MBP对LBNP诱导的中枢性血容量不足反应调节的一致性，将受试者分为2组。一致性组倾向于表现出一致的心率斜率（通过线性回归计算的心率随时间的变化率），而不一致组的受试者则不易分类。MBP维持一致的受试者表现出心血管控制反应一致的模式，而在维持MBP方面不太成功的受试者在4次测试中表现出的模式不太明确。
