倾斜床模拟推拉动作下心率和血压变化

目的建立倾斜床模拟推拉动作模型 ,并观察其引发的心血管反应性特点。方法以 1 0名健康歼击机飞行员为被试者 ,随机进行 3次 90°立位 (HUT)和 90°倒立位 (HDT)体位转换试验 ,HUT 1min→HDT 1 0s→HUT 1min ,第 2、3次体位转换时HDT的持续时间分别为 1 5s和 2 0s。床体旋转速度为45°/s。间隔 4s监测一次血压 ,连续记录心电图。结果在HDT期间 ,各时间心率和血压较基础HUT明显下降。随后HUT时 ,除 1 1～ 1 5s血压外 ,其余各时间心率和血压较基础HUT明显下降。结论采用倾斜床可以模拟推拉动作所引起的心血管的反应 ,故其可作为推拉动作的模型

Changes in Heart Rate and Blood Pressure under Push Pull Maneuver Simulated on a Tilt Table

Objective. Push-pull maneuver (PPM) was simulated using a tilt table to assess detailed cardiovascular responses and the simulation model. Method. Ten healthy fighter pilots were exposed to 3 times transition of body position of head-up tilt (HUT) for 1 min-->head-down tilt (HDT) for 10 s, 15 s and 20 s respectively-->HUT for 1 min in randomized sequences. The rate of tilt table rotation was 45 degrees /s. Heart-level arterial blood pressure was monitored with 4 s intervals, and HR was continuously monitored by ECG. Result. HR and BP fell significantly during HDT compared with those during HUT; upon subsequent HUT, HR and BP were significantly less than those during previous HUT, except BP at 11-15 s. Conclusion. Cardiovascular responses to PPM can be simulated with a tilt table. It is suggested that the tilt table model is valid in simulating the PPM.