Patent ID: 7195606
Filing Date: 2007-03-27
Classification: A61B

Abstract:
1. A syringe for withdrawal of blood from a patient and for subsequent injection of at least part of the blood components back into the patient, said syringe comprising: a syringe body having, at its lower end, a nozzle to which means for connection to a patient's blood vessel are attachable; a hollow, cylindrical piston rod having an inner bottom surface and being slidably disposed in said syringe body and carrying, at its lower end, a piston sealingly fitting said body, said piston rod having a gripping disk at its upper end; a plasma vessel disposed within and slidingly fitting said hollow piston rod, the lower end of said vessel being closed and carrying a hollow needle through which a liquid can enter said vessel via said hollow needle; a helical compression spring surrounding said needle and positioned between said plasma vessel and said inner bottom surface of said piston rod; wherein, by pulling up said piston rod, whole blood from said patient is drawn into said syringe body, said whole blood then being separated by centrifuging into a plasma component and a packed-cells component; and wherein, subsequently, by applying force to the upper, protruding end of said plasma vessel, said hollow needle is caused to perforate said piston, whereupon pushing down said piston rod causes said separate plasma component to be forced through said needle into said plasma vessel; whereinafter, when ceasing to apply said force to said end, said hollow needle is withdrawn from said piston by the restoring force of said spring.