[Effect of negative pressure and occluding cuffs on the intravascular pressure in the lower extremity of the healthy human being].

The effect of local negative pressure on the leg (with a bladder sealed above the knee) and occlusion cuffs (located as close as possible to Poupart's ligament) on the leg intravascular pressure was investigated in recumbency. In two experimental runs 8 healthy volunteers participated. Each of the two exposures was used at two levels: local negative pressure at -50 and -100 mm Hg and occlusion cuffs at +40 and +60 mm Hg with the exposure time averaging 5-7 min. Catheters were inserted into the femoral artery and vein, and arteries and veins of the back of the foot. The arterial pressure remained unchanged during both exposures: local negative pressure and occlusion cuffs. Upon exposure to local negative pressure the venous pressure in the back of the foot (with respect to the atmospheric pressure) did not change and in the femoral vein decreased. Upon exposure to occlusion cuffs the venous pressure in the back of the foot increased noticeably and in the femoral vein decreased slightly. It is concluded that none of the exposures can reproduce the major gravitational effect on leg vessels, i.e. characteristic changes in gradients of the intravascular (transmural) pressure.