体位改变对Valsalva动作心率、血压响应模式的影响

Posture shift alters pattern of heart rate and blood pressure response during valsalva maneuver

目的 比较不同体位下进行 Valsalva动作时 ,心血管响应型式的差别 .方法 在 - 15°头低位倾斜、水平仰卧和+75°头高位倾斜三种体位下 ,分别进行 4k Pa /30 s的 Valsal-va动作 ,并记录逐跳心率及动脉血压变化 .结果 +75°头高位倾斜体位下 ,心率在 相的增高幅度最大 ;在 相时呈降低变化 ,而在另外两种体位下则呈升高变化 .血压在 相前期的降低幅度以在 - 15°头低位倾斜体位下为最小 ,在 +75°头高位倾斜体位下为最大 . +75°头高位倾斜体位下血压在 相呈升高反应 ,而在 - 15°头低位倾斜和水平仰卧体位下血压呈典型降低变化 .体位改变对 Valsalva动作 II相心率、血压响应模式的影响最大 .结论 体位改变可引起中心血量重新分配及自主神经均衡性改变 ,故对

AIM To examine the influence of posture shift on the pattern of heart rate and blood pressure response to Valsalva. METHODS Thirty seconds Valsalva maneuver strains at 4 kPa were performed under -15° head down tilt, supine or +75° head up tilt posture, and the beat by beat changes of heart rate and blood pressure were noninvasively recorded and analyzed. RESULTS The increasing change of heart rate for phase Ⅱ under +75° head up tilt was beyond that under the other two postures. Under +75° head up tilt, the heart rate decreased during phase Ⅲ, whereas under horizontal supine or -15° head down tilt posture, the heat rate manifested an increasing change. The decreasing change of blood pressure during early phase Ⅱ was lowest under -15° head down tilt, and highest under +75° head up tilt. Blood pressure increased during phase Ⅲ under +75° head up tilt, and decreased under other two postures. CONCLUSION Posture shift alters the response pattern of heart rate and blood pressure during Valsalva maneuver, by circulating blood volume redistribution and autonomic balance shift to sympathetic predomination.