Christen Y, Wutschert R, Weimer D, de Moerloose P, Kruithof EK, Bounameaux H.
Effects of intermittent pneumatic compression on venous haemodynamics and
fibrinolytic activity.

Blood Coagul Fibrinolysis 1997 Apr;8(3):185-90

Department of Internal Medicine, University Hospital of Geneva, Switzerland.

Pneumatic intermittent compression is an effective method to prevent
postoperative venous thromboembolism. Its efficacy has been ascribed to both a
haemodynamic action (increase of blood flow velocity) and a stimulation of
endogenous fibrinolytic activity [via the production of tissue-type plasminogen
activator (t-PA) by the vascular endothelium]. The relative contribution of these
two effects is still debated. In a randomized, cross-over study in ten healthy
volunteers, we compared the haemodynamic and fibrinolytic effects of two
different pneumatic intermittent compression devices: a classical, low-pressure,
whole-leg boots system, and a novel, high-pressure, plantar compression system.
The study was performed at rest, to compare haemodynamics and fibrinolytic
activity modifications, and under induced venous leg stasis, in order to compare
the two compression systems in experimental conditions mimicking laparoscopic
surgery. Our data show that (1) a pneumatic compression device that exerts its
compression on the plantar venous plexus only induced an increase of venous blood
peak velocity and flow in the common femoral vein that is very similar to that
induced by the classical whole-leg boots compression system; (2) the venous
stasis induced by an external pressure mimicking the conditions of laparoscopic
surgery further increased the absolute velocity and flow increase, with the two
intermittent compression systems tested; (3) no changes of t-PA or plasminogen
activator-inhibitor 1 antigens were observed with either pneumatic compression
device. In conclusion, the present study indicates that the antithrombotic effect
of mechanical prophylaxis is probably mainly due to its ability to increase
venous peak velocity and flow, especially under venous stasis conditions.