Blood volume in the legs of healthy volunteers and the ability of grad
uated compression hosiery to reduce that volume were investigated with
gamma scintigraphy. Changing posture from supine to upright, or pneum
atic thigh cuffs inflated to either 20 or 40 mmHg with the subject sup
ine, significantly increased leg blood volumes; the mean increase was:
upright 126 ml, 20 mmHg cuff 44 ml, and 40 mmHg cuff 113 ml. A signif
icant trend in reducing these volumes was noted in three brands of com
mercially available stockings, with the subject supine and without thi
gh cuffs (Page's L trend 132.5, P<0.01) and when cuffs were applied at
20 mmHg (Page's L trend 128, P=0.05). Few of the commercially availab
le stockings delivered the 'standard' compression profile of 18 mmHg a
t the ankle, 14 mmHg at the calf and 8 mmHg at the upper thigh. The ef
fects of other compression profiles were assessed, using custom-made s
tockings, and pneumatic cuffs inflated to 20 mmHg applied to the upper
thighs to impede venous return. There was no consistent reduction of
blood volume in the popliteal region, although decreases were seen in
the upper and lower calf. The major determinant of performance was com
pression at the calf; the ankle to calf compression gradient was not i
mportant. Stockings with a profile of 16.8 mmHg at the ankle, 14.5 mmH
g at the calf and 6.4 mmHg at the upper thigh performed best.