[Effect of different Anti-G suits on lower limb blood flow]

To study effects of different Anti-G suits (AGS) and different inflation pressure on human cardiac system, changes in lower limb arterial blood flow (BF), heart rate and blood pressure in 5 male subjects with three bladder coverage AGS and a capstain AGS were observed and recorded until inflation pressure reached to its maximum. The percent of bladder coverage was about 30%, 65% and 90% of lower body for three bladder AGS. All AGS were inflated to maximum pressure in +1Gz seating position. The results showed that calf BF, could be blocked by bladder AGS, and the relationship between the mean pressure for BF block and the percentage of bladder coverage was y = 29.66 - 16.35x. (P < 0.0001, r = -0.9229). While the thigh and calf BF was not blocked in subjects with the capsule AGS. The results indicate that the effect of "the higher bladder coverage AGS + lower IP" is probably equal to that of "the lower bladder coverage AGS + higher IP" in holding calf BF.