Cardinal Health

Preventing Venous Thromboembolism: A Healthcare Professional Guide to Intervention 22 Foot Impulse Technology (FIT). Mechanism of Action. The A-V Impulse™ foot compression system is a DVT prophylaxis technology that mimics the natural haemodynamic process of the foot’s ambulatory weight-bearing heel-to-toe strike (walking). When walking, upon every step, the plantar venous plexus (arch of the foot) is flattened, causing an immediate evacuation of blood from the plexus of veins in the bottom of the foot. This action sends a column of blood up the leg and back to the heart. Numerous peer-reviewed clinical studies have documented the A-V Impulse™ foot compression system’s efficacy in helping to prevent VTE as well as post-operative swelling and pain. Mechanism of Action Stasis Prevents distal trapping and ensures clearance behind valve cusps/ soleal sinuses Increases blood flow velocity Reduces venous stasis Maximises blood flow Coagulation Changes Stimulates release of Endothelial Derived Relaxing Factor (EDRF) which inhibits platelet aggregation The A-V Impulse™ Addresses Two Components of Virchow's Triad Vessel Wall Damage Coagulation Changes Stasis Virchow’s Triad Popliteal vein velocity increased 250%over baseline 46 Stimulates the release of EDRF inhibiting platelet aggregation 47 Coagulation Prothrombin Thrombin Fibrinogen Fibrin Thrombus Fibrinolysis Plasminogen Plasmin Fibrin Degradation Products (FDP) Increased Platelet Aggregation Figure 4. Coagulation & Fibrinolysis Cascade Figures 4. identifies the stages where the A-V Impulse’s™ mechanism of action plays a role in the coagulation cascade.