Subcutaneous arterio-venous shunt with valve

摘要

A totally subcutaneous arterio-venous valved shunt, wherein no elements of the shunt are exposed supracutaneously, comprises a curved tubular shunt extending between an artery and a vein in a patient, with a pair of valves subcutaneously mounted in outlets in the shunt. The valves open and close fluid passages to the interior of the shunt upon axial movement of valve members. In use, a hollow needle is inserted through the patient's skin and mounted in an outlet opening in each valve member. The valve member is moved axially by the needle to open and close the valve and provide access to the blood flowing through the shunt. In a dialysis operation, blood is diverted to flow out of one (arterial) valve, through the dialyzer, and back through another (venous) valve of the subcutaneous shunt into the patient. Alternatively, one valve can be used for both outflow and inflow. On completion of dialysis, the valves are closed and the arterial and venous needles are withdrawn from the patient. When a single valve is used, a single needle suffices for both outflow and inflow.