A flush syringe assembly comprising: a barrel including a side wall having an inside surface defining a chamber for retaining fluid, an open proximal end, a distal end including a distal wall with a first tip extending distally therefrom having a first passageway therethrough in fluid communication with said chamber, and a plunger rod disposed within the barrel, the plunger rod comprising a distal portion and a proximal portion, the plunger rod further comprising a distal end including a stopper slidably positioned in fluid-tight engagement with the inside surface of the barrel for drawing fluid into and driving fluid out of the chamber by movement of the stopper relative to the barrel, the plunger rod extending outwardly from the open proximal end of the barrel, the stopper having a distal surface; characterized in that, the flush syringe assembly further comprises a reservoir collar, wherein the first tip adapted for connection to the reservoir collar; the reservoir collar mounted on the distal wall of the barrel and surrounding the first tip, the reservoir collar including at least one side wall having an inside surface defining a compartment containing a disinfectant or antimicrobial agent, a thread on the inside surface for connection to the hub of a vascular access device, a sealed distal end, a sealed proximal end adjacent the distal wall of the barrel, with a second tip extending distally therefrom having a second passageway therethrough in fluid communication with said first passageway, the second tip adapted for connection to a hub of a vascular access device, with disinfection of the hub of the vascular access device by the disinfectant or antimicrobial agent. a barrel including a side wall having an inside surface defining a chamber for retaining fluid, an open proximal end, a distal end including a distal wall with a first tip extending distally therefrom having a first passageway therethrough in fluid communication with said chamber, and a plunger rod disposed within the barrel, the plunger rod comprising a distal portion and a proximal portion, the plunger rod further comprising a distal end including a stopper slidably positioned in fluid-tight engagement with the inside surface of the barrel for drawing fluid into and driving fluid out of the chamber by movement of the stopper relative to the barrel, the plunger rod extending outwardly from the open proximal end of the barrel, the stopper having a distal surface; characterized in that, the flush syringe assembly further comprises a reservoir collar, wherein the first tip adapted for connection to the reservoir collar; the reservoir collar mounted on the distal wall of the barrel and surrounding the first tip, the reservoir collar including at least one side wall having an inside surface defining a compartment containing a disinfectant or antimicrobial agent, a thread on the inside surface for connection to the hub of a vascular access device, a sealed distal end, a sealed proximal end adjacent the distal wall of the barrel, with a second tip extending distally therefrom having a second passageway therethrough in fluid communication with said first passageway, the second tip adapted for connection to a hub of a vascular access device, with disinfection of the hub of the vascular access device by the disinfectant or antimicrobial agent.