Yao Y J, Wu X Y, Sun X Q, Hao W Y, Qiao Z L, Jiang S Z
Department of Aerospace Medicine, The Fourth Military Medical University, Xi'an, China.
Space Med Med Eng (Beijing). 1999 Apr;12(2):97-100.
Objective. To investigate whether LBNP during 21 d -6 degrees head-down tilt (HDT) would modify orthostatic tolerance. Method. 12 healthy males, age 23.7 +/- 5.0, were exposed to -6 degrees HDT for 21 d. 6 of them received -4.0 kPa LBNP sessions for 1 h/d from 15th day to 21st day of HDT. The other 6 served as control. HUT + 75 degrees, 20 min orthostatic tolerance test were done before, on day 10 and on day 21 of HDT. Result. During HUT + 75 degrees, 20 min orthostatic tolerance test on day 10 of HDT, 5 subjects of the control group and 4 of the LBNP group presented presyncopal or syncopal signs and symptoms, the average standing time of both groups were shorter than those of the pre-HDT (p<0.05). During HUT + 75 degrees, 20 min orthostatic tolerance test on day 21 of HDT, 5 subjects of the control group and one subject of the LBNP group presented presyncopal or syncopal signs and symptoms, the average standing time of control group reduced significantly as compared with those of pre-HDT(P<0.05), also significantly shorter than those of LBNP group (P<0.05). Conclusion. The present study clearly shows that the use of LBNP could alleviate the bed rest-induced orthostatic intolerance.
目的。研究在21天 -6°头低位倾斜（HDT）期间进行下体负压（LBNP）是否会改变直立耐力。方法。12名年龄为23.7±5.0岁的健康男性，接受-6°HDT 21天。其中6人在HDT的第15天至第21天每天接受1小时-4.0 kPa的LBNP治疗。另外6人作为对照组。在HDT前、第10天和第21天进行头高位倾斜（HUT）+75°、20分钟的直立耐力测试。结果。在HDT第10天进行HUT+75°、20分钟直立耐力测试时，对照组5名受试者和LBNP组4名受试者出现接近晕厥或晕厥的体征和症状，两组的平均站立时间均短于HDT前（p<0.05）。在HDT第21天进行HUT+75°、20分钟直立耐力测试时，对照组5名受试者和LBNP组1名受试者出现接近晕厥或晕厥的体征和症状，对照组的平均站立时间与HDT前相比显著缩短（P<0.05），也显著短于LBNP组（P<0.05）。结论。本研究清楚地表明，使用LBNP可减轻卧床休息引起的直立不耐受。
