Image Number 4 for United States Patent #6866653.
A syringe, which may be pre-filled, and a method of using the syringe is disclosed to provide sequential injection of two different fluids without mixing thereof. The syringe comprises in a first version a plunger and an intermediate disc sealingly disposed within a generally cylindrical barrel, with an outlet portion distal of the barrel, the outlet portion being generally larger in diameter so that as the disc is advanced into it far enough to substantially inject the first fluid the disc loses sealing engagement and the second fluid is then expelled around the disc and through the syringe opening. Baffles are provided within the outlet portion to prevent the disc from inadvertently sealing the opening, and channels may be provided around the baffles. In a second version a bag is provided adjacent the plunger, with the first fluid being contained within the barrel and the second fluid being contained within the bag, and at least one barb is provided in the bottom of the syringe to burst the bag after the first fluid is expelled to thereby expel the second fluid.