Flush syringe having anti-reflux stopper

• US 7,331,942 B2
• Filed: 09/23/2003
• Issued: 02/19/2008
• Est. Priority Date: 09/23/2003
• Status: Active Grant

• Current Assignee: Becton, Dickinson & Co
• Original Assignee: Becton, Dickinson & Co
• Inventors: Timko, James John, Alheidt, Thomas A.
• Primary Examiner(s): WILLIAMS, CATHERINE SERKE
• Application Number:
  US10/668,725
• Publication Number:
  US 20050065478A1
• Time in Patent Office: 1,610 Days
• Field of Search: 604/187, 604/192, 604/201, 604/218, 604/225, 604/244, 604/256
• US Class Current: 604/218
• CPC Class Codes: A61M 2005/31523 for reducing reflux
• CPC Class Codes: A61M 5/31511 Piston or piston-rod constructions, e.g. connection of piston with piston-rod A61M5/5066 takes precedence

Abstract

An I.V. flush syringe assembly includes a barrel having an inside surface defining a chamber for retaining fluid, an open proximal end and a distal end including a distal wall with an elongate tip extending distally therefrom having a passageway therethrough in fluid communication with the chamber. A plunger having an elongate body portion and a stopper slidably positioned in fluid-tight engagement with the inside surface of the barrel is provided. Anti-reflux structure for controlling stopper deflection when fluid has been delivered from the chamber and the stopper is in contact with the distal wall is provided.

Claims

1. An I.V. flush syringe assembly comprising:

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 a distal wall with an elongate tip extending distally therefrom having a passageway therethrough in fluid communication with said chamber;

a plunger including an elongate body portion having a proximal end, a distal end and a stopper slidably positioned in fluid-tight engagement with said inside surface of said barrel for drawing fluid into and driving fluid out of said chamber by movement of said stopper relative to said barrel, said elongate body portion extending outwardly from said open proximal end of said barrel; and

anti-reflux means comprising said stopper having a conically shaped distal surface and said inside surface of said barrel at said distal wall being conically shaped wherein a total included angle of said inside surface of said barrel at said distal wall is greater than a total included angle of said stopper distal surface by at least 6°

, wherein upon delivery of fluid from said chamber, said stopper contacts the distal end of the barrel and seals said passageway so that stopper deflection is controlled.

2. The syringe assembly of claim 1 wherein said total included angle of said stopper distal surface is about 110°

.

3. The syringe assembly of claim 1 wherein the total included angle conically shaped inside surface of said distal wall of said barrel is about 120°

.

4. The syringe assembly of claim 1 further including at least one projection on said distal surface of said stopper positioned mostly in a space between said distal surface and said conically shaped inside surface of said distal wall when said distal surface of said stopper first contacts said conically shaped inside surface.

5. The syringe assembly of claim 1 including flush solution in said chamber.

6. The syringe assembly of claim 5 further including a tip cap releasably connected to said tip of said syringe barrel for sealing said passageway.

7. The syringe assembly of claim 5 wherein said flush solution is selected from the group consisting of saline flush solution and heparin lock flush solution.

8. The syringe assembly of claim 1 wherein said stopper is made of material selected from the list consisting of thermoplastic elastomers, natural rubber, synthetic rubber, thermoplastic materials and combinations thereof.

9. The syringe assembly of claim 1 further comprising a needle assembly including a cannula having a proximal end, a distal end and a lumen therethrougb, and a hub having an open proximal end containing a cavity and a distal end attached to said proximal end of said cannula so that said lumen is in fluid communication with said cavity, said needle assembly being removably attached to said tip of said barrel through engagement of said tip to said cavity so that said lumen is in fluid communication with said chamber.

10. An I.V. flush syringe assembly comprising:

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 a distal wall with an elongate tip extending distally therefrom having a passageway therethrough in fluid communication with said chamber;

a plunger including an elongate body portion having a proximal end, a distal end and a stopper slidably positioned in fluid-tight engagement with said inside surface of said barrel for drawing fluid into and driving fluid out of said chamber by movement of said stopper relative to said barrel, said elongate body portion extending outwardly from said open proximal end of said barrel; and

a tip cap releasably connected to said tip of said syringe barrel for sealing said passageway;

a quantity of flush solution in said chamber between said stopper anti said distal wall;

anti-reflux means for controlling stopper deflection when fluid has been delivered from said chamber and said stopper is in contact with said distal wall, said anti-reflux means including said stopper having a conically shaped distal surface and said inside surface of said barrel at said distal wall being conically shaped wherein a total included angle of said inside surface of said barrel at said distal wall being greater Than a total included angle of said distal surface of said stopper by at least 6°

so that said stopper seals said passageway when said stopper contacts said distal wall; and

at least one projection on said distal surface of said stopper, said at least one projection having a distal surface the same angle as said distal surface of said inside surface of said barrel and positioned mostly in the space between said distal surface and said conically shaped inside surface of said distal wall when said distal surface first contacts said conically shaped inside surface.

11. The IV. flush syringe assembly of claim 10, wherein said at least one projection is positioned away from the center of said distal surface of said stopper so that said at least one projection does not interfere with the seal created when said stopper contacts said distal wall of said barrel.

12. A method of flushing a catheter comprising the steps of:

(a) providing a syringe assembly having 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 a distal wall with an elongate tip extending distally therefrom having a passageway therethrough in fluid communication with said chamber, a plunger including an elongate body portion having a proximal end, a distal end, and a stopper slidably positioned in fluid-tight engagement with said inside surface of said barrel for drawing fluid into and driving fluid out of said chamber by movement of said stopper relative to said barrel, said elongate body portion extending outwardly from said open proximal end of said barrel, a quantity of flush solution in said chamber, and anti-reflux means comprising said stopper having a conically shaped distal surface and said inside surface of said barrel at said distal wall being conically shaped wherein said total included angle of said inside surface of said barrel at said distal wall is greater than said total included angle of said stopper distal surface by at least 6°

, for controlling stopper deflection when said flush solution has been delivered from said chamber and said stopper is in contact with said distal wall;

(b) providing a catheter having a proximal end, a distal end a passageway therethrough and a housing having a hollow interior connected to said catheter and in fluid communication with said passageway, said housing having an access valve for allowing fluid communication with said hollow interior;

(c) placing said distal end of said catheter in a blood vessel;

(d) engaging said elongate tip of said barrel with said access valve so that said passageway of said syringe barrel is in fluid communication with said hollow interior of said housing;

(e) applying farce to said plunger to move said plunger in a distal direction with respect to said barrel so that said flush solution in said chamber flows through said passageway into said hollow chamber of said housing and through said passageway of said catheter;

(f) continue applying force to the plunger until said stopper contacts and presses against said distal wall of said barrel forming a seal around said passageway; and

(g) disengaging said elongate tip from said access valve.

13. A method of flushing a catheter comprising the steps of:

(a) providing a syringe assembly having a barrel including a cylindrical sidewall including an inside surface defining a chamber for retaining fluid, an open proximal end and a distal end including a distal wall with an elongate tip extending distally therefrom having a passageway therethrough in fluid communication with said chamber, a plunger including an elongate body portion having a proximal end, a distal end, and a stopper slidably positioned in fluid-tight engagement with said inside surface of said barrel for drawing fluid into and driving fluid out of said chamber by movement of the stopper relative to said barrel, said elongate body portion extending outwardly from said open proximal end of said barrel, a quantity of flush solution in said chamber, a needle assembly including a cannula having a proximal end, a distal end and a lumen therethrough and a hub having an open proximal end containing a cavity and a distal end attached to said proximal end of said cannula so that said lumen is in fluid communication with said cavity, said needle assembly being attached to said tip of said barrel so that said lumen is in fluid communication with said chamber, and anti-reflux means comprising said stopper having a conically shaped distal surface and said inside surface of said barrel at said distal wall being conically shaped wherein said total included angle of said inside surface of said barrel at said distal wall is greater than said total included angle of said stopper distal surface by at least 6°

, for controlling stopper deflection when said flush solution has been delivered from said chamber and said stopper is in contact with said distal wall;

(b) providing a catheter having a proximal end, a distal end and a passageway therethrough and a housing having a hollow interior connected to said catheter and in fluid communication with said passageway, said housing having a septum for allowing fluid communication with said hollow interior;

(c) placing said distal end of said catheter in a blood vessel;

(d) forcing said distal end of said cannula through said septum so that said lumen is in fluid communication with said hollow interior of said housing;

(e) applying force to said plunger to move said plunger in a distal direction with respect to said barrel so that said flush solution in said chamber flows through said passageway into said hollow chamber of said housing and through said passageway of said catheter;

(f) continue applying force to the plunger until said stopper contacts and presses against said distal wall of said barrel, forming a seal around said passageway; and

(g) withdrawing said cannula from said septum.