Positive displacement flush syringe

Abstract

A flush syringe assembly comprises a barrel including a cylindrical side wall having an inside surface defining a chamber for retaining fluid, an open proximal end and a distal end including an elongate tip extending distally therefrom having a passageway in fluid communication with the chamber. A plunger including an elongate body portion has a stopper at its distal end. The stopper is slidably positioned in fluid-tight engagement with the inside surface of the barrel for driving fluid out of the chamber. The distal end of the stopper is configured to collapse while fluid is being driven though the passageway through motion of a plunger and to continue to drive fluid through the passageway after motion of the plunger has stopped.