Prophylactic measure DVT includes -

Heparin anticoagulates by binding to and accelerating the activity of antithrombin,thus preventing additional thrombus formation and permitting endogenous fibrinolytic mechanisms to lyse clot that already has formed.Warfarin is a vitamin K antagonist that prevents carboxylation activation of coagulation factors 2,7,9,10.Daily use of below-knee 30 to 40 mmHg vascular compression stockings also act as a prophylactic measure for DVT. Reference:Harrison's medicine:18th edition,page no:2175