Dual chamber syringe apparatus

• US 5,971,953 A
• Filed: 01/09/1998
• Issued: 10/26/1999
• Est. Priority Date: 01/09/1998
• Status: Expired due to Fees

• Current Assignee: Coastal Pharmaceuticals Incorporated (Mayne Pharma)
• Original Assignee: Coastal Pharmaceuticals Incorporated (Mayne Pharma)
• Inventors: Bachynsky, Nicholas
• Primary Examiner(s): Stright, Ronald
• Assistant Examiner(s): Gring, Kent
• Application Number:
  US09/005,221
• Time in Patent Office: 655 Days
• Field of Search: 604/89, 604/88, 604/90, 604/91, 604/92, 604/181, 604/184, 604/187, 604/191
• US Class Current: 604/90
• CPC Class Codes: A61M 2005/3109 Caps sealing the needle bore by use of, e.g. air-hardening adhesive, elastomer or epoxy resin
• CPC Class Codes: A61M 2005/3123 having air entrapping or venting means, e.g. purging channels in pistons
• CPC Class Codes: A61M 2005/3128 Incorporating one-way valves, e.g. pressure-relief or non-return valves
• CPC Class Codes: A61M 2005/31598 having multiple telescopically sliding coaxial pistons encompassing volumes for components to be mixed
• CPC Class Codes: A61M 5/284 comprising means for injection of two or more media, e.g. by mixing
• CPC Class Codes: A61M 5/31511 Piston or piston-rod constructions, e.g. connection of piston with piston-rod A61M5/5066 takes precedence
• CPC Class Codes: A61M 5/31525 Dosing burettes, pipettes B01L3/02
• CPC Class Codes: A61M 5/31551 including axial movement of dose setting member
• CPC Class Codes: A61M 5/31561 using freely adjustable volume steps
• CPC Class Codes: A61M 5/31591 Single dose, i.e. individually set dose administered only once from the same medicament reservoir, e.g. including single stroke limiting means
• CPC Class Codes: A61M 5/31596 comprising means for injection of two or more media, e.g. by mixing

Abstract

A dual chamber syringe for dispensing a dry medicine that is to be reconstituted just prior to administration to a patient includes a syringe housing having an outer wall and proximal and distal end portions. A syringe bore extends between the proximal and distal end portions. The bore is divided during use into upper and lower chambers for containing medicinal contents that are to be first mixed and then dispensed. In the preferred embodiment, the chambers contain an upper liquid component and a lower dry component. A first lower piston occupies a position generally in between the upper and lower chambers. The first lower piston engages a plurality of ribs at an enlarged diameter bypass portal section of the syringe housing with multiple longitudinally extending channels after the user applies pressure to a second upper piston in the bore and above the upper chamber. Continued downward movement of the two pistons causes the two components to mix to be dispensed from the distal end of the syringe. The ribs have recess portions that form a dampening slot for engaging the periphery of the first lower piston as it travels distally. This enables the diluent fluid to completely mix with the dry drug product before the second, upper piston engages the lower piston to force it down during administration of the reconstituted product to the patient.

Claims

1. A dual chamber syringe for dispensing a dry medicine that is to be reconstituted just prior to administration to a patient comprising:

a) a syringe housing having an outer wall and proximal and distal end portions;

b) a bore that extends between the proximal and distal end portions, the bore including upper and lower chambers for containing medicine contents to be dispensed including an upper liquid component and a lower dry component;

c) a dispensing portion at the distal end of the housing for receiving the medicine contents of the bore;

d) a first piston that occupies a position generally in between the upper chamber and the lower chamber, the first piston being movable within the bore between upper and lower positions during use;

e) a second piston positioned at the proximal end of the housing and movable within the bore between upper and lower positions during use;

f) an enlarged diameter section of the housing defining a bypass bore section for enabling fluid travel between the upper and lower chambers;

g) a plurality of bypass channels positioned in the bypass bore separated by a plurality of ribs, the ribs having recessed portions for receiving the periphery of the first piston as fluid flows through the longitudinal channels; and

h) wherein the first piston seals the contents of the upper chamber away from the channels and lower chamber in the upper position.

2. The dual chamber syringe of claim 1 wherein the enlarged diameter section includes a cylindrically-shaped portion.

3. The dual chamber syringe of claim 1 wherein the enlarged diameter section of the housing has an external wall with inner and outer surfaces and the bypass channels are formed on the inner surface of the wall.

4. The dual chamber syringe of claim 1 wherein the bore is of a generally uniform diameter over a majority of the length of the syringe housing.

8. The dual chamber syringe of claim 1 wherein the first piston has an O-ring like seal that forms a seal between the first piston and the housing when the first piston is in the upper position.

5. A dual chamber syringe for dispensing a dry medicine that is to be reconstituted just prior to administration to a patient comprising:

a) a syringe housing having an outer wall and proximal and distal end portions;

b) a bore that extends between the proximal and distal end portions, the bore including upper and lower chambers for containing medicine contents to be dispensed including an upper liquid component and a lower dry component;

c) a dispensing portion at the distal end of the housing for receiving the medicine contents of the bore;

d) a first piston that occupies a position generally in between the upper chamber and the lower chamber, the first piston being movable within the bore between upper and lower positions during use;

e) a second piston positioned at the proximal end of the housing and movable within the bore between upper and lower positions during use;

f) an enlarged diameter section of the housing defining bypass bore section for enabling fluid travel between the upper and lower chambers;

g) a plurality of bypass channels positioned in the bypass bore separated by a plurality of ribs, the ribs having dampening slots for holding the first piston as fluid flows through the longitudinal channels;

h) wherein the first piston seals the contents of the upper chamber away from the channels and lower chamber in the upper position; and

i) a semi-permeable membrane positioned at the first piston for enabling air flow but not water flow through the first piston.

6. The dual chamber syringe of claim 5 wherein the first piston is a transverse member that extends across the bore forming an engagement with the external wall.

7. The dual chamber syringe of claim 6 wherein the first piston has an opening therethrough.

9. A dual chamber syringe for dispensing a dry medicine that is to be reconstituted just prior to administration to a patient comprising:

a) a syringe housing having an outer wall and proximal and distal end portions;

b) a bore that extends between the proximal and distal end portions, the bore including upper and lower chambers for containing medicine contents to be dispensed including an upper liquid component and a lower dry component;

c) a dispensing portion at the distal end of the housing for receiving the medicine contents of the bore;

d) a first piston that occupies a position generally in between the upper chamber and the lower chamber, the first piston being movable within the bore between upper and lower positions during use;

e) a second piston positioned at the proximal end of the housing and movable within the bore between upper and lower positions during use;

f) an enlarged diameter section of the housing defining bypass bore section for enabling fluid travel between the upper and lower chambers;

g) a plurality of bypass channels positioned in the bypass bore separated by a plurality of ribs, the ribs having dampening slots for holding the first piston as fluid flows through the longitudinal channels; and

h) wherein the first piston seals the contents of the upper chamber away from the channels and lower chamber in the upper position;

i) wherein the first piston has a central opening and a hollow tube connected to the piston at the opening so that air can flow through the central opening and tube and further comprising a membrane that allows air but not water to flow through the opening and hollow tube.

10. The dual chamber syringe of claim 9 wherein a plurality of the longitudinal channels are generally parallel.

11. A dual chamber syringe, comprising:

a) a syringe housing having an outer wall and proximal and distal end portions;

b) a syringe bore that extends between the proximal and distal end portions, the bore defining upper and lower chambers for containing medicinal contents to be dispensed including an upper liquid component and a lower dry component;

c) a dry medicine contained within the lower chamber;

d) a liquid diluent contained within the upper chamber for reconstituting the dry medicine just prior to administration to a patient;

e) a dispensing needle at the distal end of the housing for receiving the medicinal contents of the bore after the liquid is used to liquify the dry medicine;

f) a first, lower piston that occupies a position generally in between the upper chamber and the lower chamber, the first piston having a central opening and being movable between upper and lower positions;

g) a second, upper piston positioned at the proximal end of the housing and sliding in the bore during use, and the first piston being movable relative to the second piston;

h) a hollow plunger for urging the second upper piston downwardly toward the distal end of the housing, the plunger having a central opening;

i) at least one longitudinal channel positioned at the center of the housing that conveys liquid in between the upper and lower chambers when the first piston moves from the upper to the lower position;

j) wherein the first piston seals the liquid contents of the upper chamber away from the dry contents of the lower chamber when the first position is in the upper position;

k) wherein the first position is positioned next to the channel when the first piston is moving from the upper position to the lower position; and

l) a hollow tube connected to the first, lower piston at the central opening, the tube being telescopingly received within the plunger central opening; and

m) a semi-permeable, hydrophobic membrane that enables air but not water to flow through the central opening of the first piston into the hollow tube and central opening of the plunger; and

n) a vent opening for venting air from the hollow tube and central opening of the plunger.

12. The dual chamber syringe of claim 11 wherein the membrane is positioned on the first piston in communication with the lower chamber.

13. The dual chamber syringe of claim 11 wherein there are a plurality of channels.

14. The dual chamber syringe of claim 11 wherein the channel comprises an enlarged diameter section of the syringe bore.

15. The dual chamber syringe of claim 14 wherein the enlarged diameter section of the syringe bore includes a plurality of longitudinally extending ribs.

16. The dual chamber syringe of claim 15 wherein the ribs have recessed portions forming a dampening slot that slows downward movement of the first piston during use.

17. The dual chamber syringe of claim 15 wherein each rib has a generally semicircular recess that receives a correspondingly shaped surface on the periphery of the first piston.

18. The dual chamber syringe of claim 11 wherein the membrane is of an oleophobic mesh material.

19. The dual chamber syringe of claim 11 wherein the plunger has an air outlet opening that enables air to flow from the plunger central opening to the surrounding atmosphere.

20. A dual chamber syringe, comprising:

a) a syringe housing having an outer wall and proximal and distal end portions;

b) a syringe bore that extends between the proximal and distal end portions, the bore defining upper and lower chambers for containing medicinal contents to be dispensed including an upper liquid component and a lower dry component;

c) a dry medicine contained within the lower chamber;

d) a liquid diluent contained within the upper chamber for reconstituting the dry medicine just prior to administration to a patient;

e) a dispensing needle at the distal end portion of the housing for receiving the medicinal contents of the bore after the liquid is used to liquify the dry medicine;

f) a first, lower piston that occupies a position generally in between the upper chamber and the lower chamber, the first piston having a central opening and being movable between upper and lower positions;

g) a second, upper piston positioned at the proximal end of the housing and sliding in the bore during use, and the first piston being movable relative to the second piston;

h) a hollow plunger for urging the second upper piston downwardly toward the distal end of the housing, the plunger having a central opening;

i) an enlarged diameter bypass portal section of the syringe housing positioned in between proximal and distal ends of the syringe housing having an enlarged diameter section of the syringe bore that provides a bypass channel for enabling diluent fluid to flow from the upper to the lower chamber, the enlarged diameter bypass portal section including means for supporting the periphery of the first, lower piston as the lower piston travels toward the lower chamber;

j) wherein the first piston seals the liquid contents of the upper chamber away from the dry contents of the lower chamber when the first piston is in the upper position;

k) wherein the first piston is positioned next to the channel when the first piston is moving from the upper position to the lower position; and

l) a hollow tube connected to the first, lower piston at the central opening, the tube being telescopingly received within the plunger central opening; and

m) a membrane that enables water but not air to flow through the central opening of the first piston into the hollow tube and central opening of the plunger; and

n) a vent opening for venting air from the hollow tube and central opening of the plunger.