[Effect of negative pressure on the lower half of the body (the Chibis suit) and of local negative pressure on central circulation in the healthy human].

Catheters were chronically implanted into pulmonary and radial arteries of 8 healthy volunteers to examine the effect of lower body negative pressure (LBNP in the Chibis suit) and local negative pressure on the leg on central circulation, oxidative metabolism and acid-base equilibrium in the blood. In 1-hour head-down tests (at -20 degrees) the effect of two regimens of LBNP (at -30 and -60 mm Hg) and local negative pressure (at -50 and -100 mm Hg) was studied, each exposure averaging 15-20 min. Both LBNP and local negative pressure induced changes in central circulation that were similar qualitatively and dissimilar quantitatively. The use of regimen I of both exposures caused more marked changes than that of regimen II.