The present disclosure relates to a safety needle assembly that is used in subcutaneous injection of a high viscosity formulation, and more particularly, to a safety needle assembly that ensures safety in subcutaneous injection of a high viscosity formulation.
Conventionally, injection has been employed as a method for delivering therapeutic agents into the body of a patient. Examples of the injection include intradermal injection, subcutaneous injection, intramuscular injection, intravenous injection, arterial injection, intraarticular injection, and epidural injection. Among these injections, for example, subcutaneous injection is used in diseases such as diabetes and rheumatism. JP 2012-509749 A (“Patent Literature 1”) proposes a subcutaneous infusion system as a system that performs subcutaneous injection. The subcutaneous infusion system is provided with a needle of 24 to 27 gauge or 18 gauge and a medication dispensing device. The needle includes a shaft having an internal duct of unvarying diameter defining a fluid pathway between openings at distal and proximal ends of the needle. A hub in fluid communication with the duct is disposed at the distal end of the needle, and the needle length from the hub to the proximal end is approximately 4 to 6 mm. The medication dispensing device is in detachable fluid communication with the needle duct and contains approximately 3 to 100 mls of a highly viscous therapeutic fluid composition. The subcutaneous infusion system of Patent Literature 1 is configured for subcutaneous delivery of the therapeutic fluid composition at a flow rate of approximately 1 to 20 ml per minute.
Health care workers have to safely handle subcutaneous injection needles. For example, if a health care worker erroneously sticks a subcutaneous injection needle used for a patient or the like into the own body (finger, for example), the health care worker may be infected with a disease. However, the system of Patent Literature 1 has no means for preventing such a sting accident and thus cannot be perfectly safe. There may be a method, as safety measure, that covers a used subcutaneous injection needle with a cylindrical cap. However, even in this method, a health care worker may erroneously stick the needle into his finger holding the cap. Therefore, this method also cannot be perfectly safe.
It is an object of the present invention to solve the above problem associated with conventional techniques and provide a safety needle assembly that ensures safety in subcutaneous injection of a high viscosity formulation.
In order to solve the above issue, one embodiment of the present invention is directed to a safety needle assembly including: a hub including a proximal end connected to a syringe and a distal end; a cannula including a proximal end connected to the distal end of the hub, a lumen extending in a longitudinal direction of the cannula, and a distal end, the cannula having a thickness of 18 to 24 gauge and a length between the hub and the distal end of 8 to 22 mm; a collar attached to the hub and including a sheath attachment part; a protector configured to cover the distal end of the cannula by being attached to the hub or the collar, the protector being detachable for exposing the distal end of the cannula; and a sheath including an opening extending along at least a part of the sheath in a longitudinal direction, the opening being capable of housing the cannula, the sheath further including: a cannula fixing part configured to fix the cannula, the cannula fixing part extending along at least a part of the sheath in the longitudinal direction; an attachment part configured to rotatably support the sheath in a direction of housing the cannula in the opening when the protector is detached to expose the distal end of the cannula, the attachment part being attached to the sheath attachment part of the collar; a projecting stopper for restricting movement, toward a distal end of the sheath, of a finger of a user pushing the sheath for housing the cannula into the opening, the stopper being disposed near a central part of the sheath in a longitudinal direction or at a position between the central part and the distal end of the sheath at an opposite side of an opening face of the opening; and a guide rib including a locking protrusion for locking the cannula inside the opening with an angle, in a side view, between a line passing through an end face of the opening of the sheath and a line passing through a surface of the cannula of 0° or more with respect to the housing direction of the cannula.
Further, certain embodiments of the present invention are preferably used for a high viscosity formulation. Further, a silicone film is preferably formed on the surface of the cannula within a range of 60% to 85% of the length from the distal end.
Further, the sheath preferably includes, as a finger guiding region with which a finger of a user operating the sheath comes into contact, a circular recess and a slope formed between the circuit recess and the stopper, the slope having a plurality of protrusions and recesses, the circular recess and the slope being located between the stopper and a proximal end of the sheath at the opposite side of the opening face of the opening.
Embodiments of the present invention make it possible to safely house the cannula in the sheath and reliably prevent a sting accident. Further, the silicone film formed on the cannula enables the cannula to be more reliably and safely housed in the sheath.
Hereinbelow, an example of safety needle assembly of the present invention will be described in detail on the basis of an embodiment illustrated in the accompanying drawings.
The safety needle assembly 10 in the present embodiment is connected to a fluid transfer device such as a syringe (hereinafter, merely referred to as “syringe”) to be used.
The safety needle assembly 10 is used in subcutaneous injection of a high viscosity formulation. The high viscosity of the high viscosity formulation indicates a viscosity of 30 cP or more.
The safety needle assembly 10 is packaged, for example, in a blister packaging which is formed by extending a plastic sheet material and connected to a syringe by a user such as a health care worker when used. Alternatively, the safety needle assembly 10 may be packaged after connected to a syringe.
Note that when each component is described, a “direction” described therein is defined by the respective directions of “UP” and “DOWN”, “FRONT” (distal end side) and “BACK” (proximal end side), and “LEFT” and “RIGHT” illustrated in
The safety needle assembly 10 illustrated in
The cannula 14 is connected to the hub 12 by a general method, for example, using an epoxy resin. The cannula 14 includes a proximal end 52 which is connected to a distal end 30 of the hub 12 and a distal end 54 which has a blade surface 50. The distal end 54 includes a needle point 14a.
The cannula 14 has a thickness of 18 to 24 gauge and a length L between the hub 12 and the distal end 54 of 8 to 22 mm. The length L indicates the length between the distal end 54 of the cannula 14, that is, the needle point 14a and the hub 12 (refer to
The thickness of 18 to 24 gauge of the cannula is suitable for injection of a high viscosity formulation. When the thickness of the cannula falls out of this value range, defective conditions occur. Specifically, when the thickness of the cannula is larger than this value range, a range of damaging tissues is expanded. On the other hand, when the thickness of the cannula is smaller than this value range, it is difficult to inject a high viscosity formulation. Further, the length L between the hub 12 and the distal end 54 of 8 to 22 mm is suitable for subcutaneous injection performed at an angle of approximately 45° with respect to a skin surface. From the above viewpoints, the thickness of the cannula is more desirably 18 to 19 gauge, and the length L is more desirably 12 mm to 16 mm.
The surface of the cannula 14 is silicone-treated to form a silicone film 55 thereon. The silicone film 55 is formed within a range of 60% to 85% of the length L between the needle point 14a and the hub 12. For example, when the length L is 13 mm, the silicone film 55 is formed up to a position that is 8 mm to 11 mm from the needle point 14a. The silicone film 55 is formed by, for example, dipping.
The silicone film 55 enables a patient to feel less pain during injection. As described below, the cannula 14 is locked by a guide rib 106 (refer to
It is preferred to mold the hub 12, the collar 16, the protector 18, and the sheath 20 as one-piece parts. However, the present embodiment is not limited to this configuration.
The collar 16 is attached to the hub 12 at a predetermined position. The protector 18 is guided by the hub 12 and attached to at least either the collar 16 or the hub 12 to thereby cover the cannula 14. The sheath 20 is pivotably attached to the collar 16. These components will be described in detail below.
As illustrated in
The distal end 30 of the hub 12 includes a plurality of stepped ribs 36 extending in the longitudinal direction. The ribs 36 facilitate coaxial attachment (in a central axis c) of the collar 16 to the hub 12.
An outer surface of the hub 12 includes a plurality of protrusions 38 extending outward in the radial direction from an outer circumferential surface of the hub 12.
A ring-shaped recessed region 40 is located at a distal side of the protrusions 38. Accordingly, step parts 42 and 44 which are adjacent to the ring-shaped recessed region 40 have larger outside diameters than the ring-shaped recessed region 40.
The proximal end 32 of the hub 12 includes a flange 46 which projects outward in the radial direction. The flange 46 is engaged with, for example, a distal end of a syringe body (not illustrated). The engagement allows the hub 12 to be connected to the syringe body (not illustrated). This connection may be performed by a known method, for example, by engaging the flange 46 with a screw (female screw) located at the distal end of the syringe body (not illustrated).
As illustrated in
The collar 16 includes a ring-shaped ridge 78b projecting inward on an inner surface thereof. The ring-shaped ridge 78b extends over the whole circumference of the inner peripheral part of the through hole 76. When the collar 16 is attached to the hub 12, the ring-shaped ridge 78b is seated onto the ring-shaped recessed region 40 (refer to
The collar 16 includes a pair of ear-shaped projections 60 (sheath attachment part) projecting outward in the radial direction. Each of the projections 60 includes a circular through hole 64 which houses therein a pin 126 of the sheath 20 (described below, refer to
That is, the pair of projections 60 enables the sheath 20 to be rotatably attached to the collar 16. More specifically, the chamfers 62 facilitate the attachment of a pair of the pins 126 of the sheath 20 to the respective projections 60 of the collar 16. When the pair of pins 126 is attached to the pair of projections 60, the projections 60 slightly bend in directions away from each other. The thickness of each of the projections 60 may be appropriately determined taking into consideration the strength for resistance to damage and the flexibility for easier attachment of the sheath 20.
The collar 16 includes a ring-shaped ridge 70 projecting outward in the radial direction. The ring-shaped ridge 70 is a component for seating the protector 18.
The collar 16 further includes a pair of sheath fixing protrusions 68. Each of the sheath fixing protrusions 68 has a substantially triangular shape, and is disposed at the opposite side of the projections 60. The sheath fixing protrusion 68 further includes a groove 72 which is engaged with a wing wall 96 (cannula fixing part) (refer to
As illustrated in
The protector 18 is attached at the position to cover the cannula 14 to thereby cover up the distal end of the cannula 14. At this time, the protector 18 is fixed to at least either the collar 16 or the hub 12. The protector 18 is detachable so as to expose the distal end 54 of the cannula 14. A seating face (not illustrated) for the collar 16 may be provided inside the protector 18 at the proximal end 82 thereof.
As illustrated in
The sheath 20 includes a finger guiding part 90, a finger guiding part 92, and a distal part 94, each of which includes a pair of side walls and a back wall. A circular recess 112 is formed on the back wall of the finger guiding part 90. The circular recess 112 is used as a finger guiding region with which a finger of a user such as a health care worker operating the sheath 20 comes into contact.
The back wall of the finger guiding part 92 is formed as a stepped slope inclined downward toward the front side. On the slope, protrusions 116 and recesses 118 are repeatedly formed so as to increase the friction against a finger of a health care worker.
The back wall of the distal part 94 includes a projecting stopper 100 which prevents a finger of a health care worker pushing the sheath 20 from further moving toward the distal end 120 of the sheath 20. The stopper 100 is formed near a central part in the longitudinal direction of the sheath 20 or at a position between the central part and the distal end 120 of the sheath 20 so that a larger moment is generated to smoothly pivot the sheath 20 when a health care worker pushes the sheath 20 with the finger.
The sheath 20 includes a collar connection mechanism 98 (attachment part) which has a pair of cylindrical pins 126. The pins 126 are attached to the respective through holes 64 of the projections 60 of the collar 16 so as to rotatably connect the sheath 20 to the collar 16. Each of the pins 126 is chamfered so as to facilitate the above connection.
As illustrated in
As illustrated in
The recess 102 holds the distal end 30 (refer to
The guide rib 106 is used for holding the cannula 14 inside the sheath 20. The guide rib 106 includes a groove 107. A locking protrusion 108 is disposed to partially close an opening of the groove 107. The locking protrusion 108 is bendable. The guide rib 106 is, for example, integrally molded with the rib 104.
When the cannula 14 is inserted into the opening 101 so as to be housed in the sheath 20, the locking protrusion 108 of the guide rib 106 is bent, which allows the cannula 14 to enter the groove 107 of the guide rib 106. At this time, since the silicone film 55 is formed on the cannula 14, the resistance against the locking protrusion 108 is small. Thus, the cannula 14 can smoothly enter the groove 107. As illustrated in
The cannula 14 is locked inside the sheath 20 by the locking protrusion 108. In this case, when, in a side view of
The cannula 14 having a thickness of 18 gauge to 24 gauge and a length L of 8 to 22 mm can be reliably locked by the guide rib 106 by increasing a distance D between the cannula 14 and the rib 104 illustrated in
As described above, the silicone film 55 is formed on the cannula 14. Thus, when the cannula 14 comes into contact with the locking protrusion 108 and enters the groove 107, it is possible to reduce the resistance of the cannula 14, and more reliably and safely lock the cannula 14 inside the sheath 20.
The components described above are arranged as illustrated in
Next, a method for using the safety needle assembly 10 will be described with reference to
As illustrated in
After the sheath 20 is pivoted, the health care worker removes the protector 18 to expose the cannula 14 as illustrated in
After finishing the use of the cannula 14, the health care worker first pivots the sheath 20 in a direction Rc toward the cannula 14 so that the safety needle assembly 10 becomes a state illustrated in
Then, the health care worker pushes the back wall of the finger guiding part 92 (refer to
As described above, in the safety needle assembly 10 in the present embodiment, the cannula 14 is covered with the sheath 20 and locked by the guide rib 106. Thus, it is possible to prevent a sting accident such that a health care worker erroneously sticks the cannula 14 into the body after using the cannula 14 and thus obtain a high safety. The guide rib 106 is easily integrally molded with the rib 104. Thus, the fixing part of the cannula 14 can be achieved at a low cost.
Further, a high operability can be achieved due to the structure of the sheath 20 which has the projecting stopper 100 (refer to
Further, the pair of wing walls 96 (refer to
Further, a health care worker can push the sheath 20 not only at the slope provided with the plurality of protrusions 116 (refer to
Further, the projections 60 (refer to
Further, each of the sheath fixing protrusions 68 (refer to
For example, if there are a plurality of cannulas 14 having different lengths, different sheaths 20 corresponding to the respective lengths may be used.
The present invention is essentially configured in the above manner. Hereinabove, an embodiment of the safety needle assembly of the present invention has been described in detail. However, the present invention is not limited to the above embodiment. It is needless to say that various improvements and modifications may be made without departing from the scope of the invention.
Number | Date | Country | Kind |
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2014-137253 | Jul 2014 | JP | national |
This application is a continuation application filed under 25 U.S.C. 111(a) claiming the benefit under 35 U.S.C. §§120 and 365(c) of PCT International Application No. PCT/JP2015/065040 filed on May 26, 2015, which claims priority to Japanese Patent Application No. 2014-137253, filed on Jul. 2, 2014. The contents of these applications are hereby incorporated by reference in their entireties.
Number | Date | Country | |
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Parent | PCT/JP2015/065040 | May 2015 | US |
Child | 15081050 | US |