Safety cannula

A coupling system for transferring fluids from a medicament-containing cartridge to an injection site comprises a fluid flow channel, a blunt cannula defining the distal end of the fluid flow channel, a needle cannula defining the proximal end of the fluid flow channel, and means for fixedly connecting the needle cannula to the blunt cannula.

What is claimed is:

1. A coupling system-cartridge-syringe holder assembly comprising in combination,

(1) a syringe holder comprising a frame, a clamp and a plunger element containing a piston stem;

(2) a cartridge loaded into the frame of said syringe holder, said cartridge comprising a hollow body filled with a medication, a sealed diaphragm on the distal end thereof and a piston axially and reciprocally slidable through the interior of said body; and

(3) a coupling system for transferring fluids from said cartridge to an injection site, said coupling system comprising:

a fluid flow channel having proximal and distal ends;

a needle cannula defining the proximal end of said fluid flow channel;

a hub attached to the distal end of said cartridge comprising a blunt cannula portion defining the distal end of said fluid flow channel and a sleeve portion which extends beyond the proximal end of said needle cannula;

wherein said cartridge can be advanced distally through said holder by rotating said clamp such that the proximal end of said needle cannula penetrates said diaphragm, and

said piston stem can be connected to said piston and actuated to drive said piston through said cartridge and expulse the fluid contents of said cartridge through said fluid flow channel into an injection site.

2. The coupling system-cartridge-syringe holder assembly of claim 1 wherein the sleeve portion of said hub has a radius of about 5 mm.

3. The coupling system-cartridge-syringe holder assembly of claim 1 wherein the distance between the end of the sleeve and the proximal end of the needle cannula is at least 2 mm.

4. The coupling system-cartridge-syringe holder assembly of claim 1 wherein said hub is fabricated of a plastic material selected from the group consisting of polyethylene, polypropylene and a polypropylene copolymer containing low density polyethylene.

5. The coupling system-cartridge-syringe holder assembly of claim 1 wherein the distal end of said needle cannula is flush with the distal end of the blunt cannula.

6. A coupling system-cartridge-syringe holder assembly comprising in combination,

(1) a syringe holder comprising a frame, a clamp and a plunger element containing a piston stem;

(2) a cartridge loaded into the frame of said syringe holder, said cartridge comprising a hollow body filled with a medication, and a piston axially and reciprocally slidable through the interior of said body; and

(3) a coupling system for transferring fluids from said cartridge to an injection site, said coupling system comprising:

a fluid flow channel having proximal and distal ends;

a needle cannula defining the proximal end of said fluid flow channel;

a hub attached to the distal end of said cartridge comprising a blunt cannula portion defining the distal end of said fluid flow channel and a sleeve portion;

wherein said piston stem can be connected to said piston and actuated to drive said piston through said cartridge and expulse the fluid contents of said cartridge through said fluid flow channel into an injection site.

7. A coupling system-cartridge-syringe holder assembly comprising in combination,

(1) a syringe holder comprising a frame, a clamp and a plunger element containing a piston stem;

(2) a cartridge comprising a hollow body filled with a medication and a piston axially and reciprocally slidable through the interior of said body; and

(3) a coupling system for transferring fluids from said cartridge to an injection site, said coupling system comprising:

a fluid flow channel having proximal and distal ends;

a needle cannula defining the proximal end of said fluid flow channel;

a hub attached to the distal end of said cartridge comprising a blunt cannula portion defining the distal end of said fluid flow channel and a sleeve portion;

wherein said piston stem can be connected to said piston and actuated to drive said piston through said cartridge and expulse the fluid contents of said cartridge through said fluid flow channel into an injection site.

8. A coupling system-cartridge-syringe holder assembly comprising in combination,

(1) a syringe holder comprising a plunger element containing a piston stem;

(2) a cartridge comprising a hollow body filled with a medication, a sealed diaphragm on the distal end thereof and a piston axially and reciprocally slidable through the interior of said body; and

(3) a coupling system for transferring fluids from said cartridge to an injection site, said coupling system comprising:

a fluid flow channel having proximal and distal ends;

a needle cannula defining the proximal end of said fluid flow channel;

a hub attached to the distal end of said cartridge comprising a blunt cannula portion defining the distal end of said fluid flow channel and a sleeve portion;

wherein said piston stem can be connected to said piston and actuated to drive said piston through said cartridge and expulse the fluid contents of said cartridge through said fluid flow channel into an injection site.

9. A coupling system-cartridge-syringe holder assembly comprising in combination,

(1) a syringe holder comprising a plunger element containing a piston stem;

(2) a cartridge comprising a hollow body filled with a medication, and a piston axially and reciprocally slidable through the interior of said body; and

(3) a coupling system for transferring fluids from said cartridge to an injection site, said coupling system comprising:

a fluid flow channel having proximal and distal ends;

a needle cannula defining the proximal end of said fluid flow channel;

a hub attached to the distal end of said cartridge comprising a blunt cannula portion defining the distal end of said fluid flow channel and a sleeve portion;

wherein said piston stem can be connected to said piston and actuated to drive said piston through said cartridge and expulse the fluid contents of said cartridge through said fluid flow channel into an injection site.