Anti-thrombtic medical instrument and catheter

An antithrombotic medical instrument comprising:

• a base (2) with a port (3) for connection to an infusion set;
• a vascular catheter (5) extending from the base (2), and comprises a main body (6) of tubular configuration and a collapsible tip made of an elastomeric material, wherein there is a distal opening in said tip configured to be opened by a trocar that extends in use through the tip opening and to collapse closed upon withdrawal of the trocar;
• a plurality of lateral conduits distributed along the length of the catheter;
• an elastomeric cover over each lateral conduit, said elastomeric cover opens with a fluid flow inside the catheter and closes when the fluid flow stops;
• said antithrombotic medical instrument characterised in that the lateral conduits are distributed longitudinally and circumferentially around the catheter, have an angle in the range of 15° to 60° to the longitudinal axis of the catheter, and directed in opposite direction of a fluid flow inside the catheter to provide a retrograde fluid flow around the catheter.