BRIEF DESCRIPTION OF THE DRAWINGS
The invention and its various embodiments is better understood by reading the description along with the accompanying drawings wherein:
FIG. 1 shows a cross sectional view of an exemplary embodiment of the filter needle of the present invention;
FIG. 1A is an illustration of an alternate form of a deformation formed in the needle illustrated in FIG. 1;
FIG. 2 shows the arrangement of FIG. 1 employed for aspirating liquid contaminated by debris from a freshly opened ampoule;
FIG. 3 is an enlarged detail showing a cover for the needle shown in FIG. 1 secured to syringe outlet;
FIG. 4 illustrates the application of force to the cover to thereby stress the needle along the deformation causing the needle to break thereat to separate the portion of the needle containing the filter from the remainder of the needle and to form a fresh point along the break.
FIG. 5 illustrates the remaining portion of the needle with the fresh new point ready to infuse uncontaminated liquid.
DESCRIPTION OF THE INVENTION
Referring to FIG. 1, an exemplary embodiment of the invention is illustrated. The invention comprises a single in-line filter needle 10, formed of a hollow shaft 12, having a proximal or inlet end 14 and a distal or outlet end 16 having a first sharp point 18. The shaft is formed with a central through opening 20 having an inner wall 22 and an outer wall 24. The through opening extends between the inlet and outlet for communicating fluids there through. The fluids are typically drugs supplied in glass ampoules, which drugs may be contaminated with debris which may result from opening the ampoules in a known manner, i.e. by fracturing the ampoule along the neck portion, discussed below. The proximal end 14 of the shaft 12 secured to a leur lock 26 adapted to be snugly secured on the end or barrel 28 of conventional syringe 30 used to aspirate liquid and to dispense liquid. The needle 10 is adapted for removable connection to the syringe, whereby a liquid may be aspirated for later use. The distal end 14 may be employed without a sharp end if desired, particularly if it is not necessary to pierce an object. However, as a practical matter it is convenient to have a sharp end. It should be understood that the terms inlet and outlet are illustrative only. It will become evident that, depending on the direction of flow an end of the needle may be an inlet or an outlet. However, for purposes of the discussion normal flow of liquid is from the syringe to the inlet 12 to the outlet 14. When flow is reversed, the convention identifying the respective ends will remain the same, but may be referred to as proximal or distal for clarity.
The needle 10 shown in FIG. 1 has a filter 32 located in the through opening 20 proximate to the sharp point 18. The filter 32 is adapted to filter small particles of which may be entrained in liquids. The filter may be a fiber or non-fiber material with pores of around 0.01 microns sufficient to filter small particles which may be found in the liquid to be aspirated.
The filter 32 may include a cylindrical filter element sized and shaped to engage and seal against the inner wall of the needle. The filter may be secured by an interference fit interior of the needle. In accordance with the invention, the filter has sufficient flow capacity to allow for rapid aspiration of liquid therethrough. The density of the filter is sufficient to trap contaminants such as glass shards.
In the invention, a frangible deformation 34 may formed on the outer wall 24 of the shaft 12 between the inlet and the outlet. The deformation may be an uninterrupted or continuous score line or it may be in the form of a saw-tooth groove as shown. The frangible deformation 34 may be formed using a cutting implement to form a score line disposed at an angle to the axis of the needle, so that when the needle is stressed the new sharp point is formed. As noted above, the score line may be continuous forming a smooth fresh sharp end, or the score line may be in the form a saw-tooth in order to cause the needle to break in such a way that the fresh tip is serrated. When pressure is applied on opposite sides of the deformation 34, the shaft 12 breaks along the score line 36, thereby forming a fresh point, discussed hereinafter.
Other forms of deformation may be applied to the shaft as desired. For example, a radial deformation 36 may be made in the outer wall 24 of the shaft as shown in FIG. 1A. The deformation may be formed by applying pressure against the outside surface of the shaft to deform the needle shaft. A mandrel may be located inside the needle passageway during the formation of the deformation or groove so as to prevent collapse of the needle and closure of the opening.
FIG. 2 shows an ampoule 38 for containing a liquid 40 therein. The ampoule has a narrow neck 42 with an irregular open end 44 formed when a closed end 46 is snapped or severed from the neck 42 in a conventional manner, i.e. by stressing the neck with a shearing force. When the ampoule is opened, debris in the form of small glass shards or particles 48 may be produced. The shards can find their way into the liquid. These particles must be removed from the liquid before it may be administered to a patient. Accordingly, the filter 32 is employed for this purpose.
The needle 10 is inserted into the neck 42 of the open ampoule 38 and the tip 16 of the needle is located therein as shown. The conventional syringe 30 is then operated to draw or aspirate the liquid 40 through the needle and into the syringe. The liquid is drawn into the needle 10 through the distal or outlet end 16, through the filter 32 in the hollow shaft 12 to the proximal end 14 and into the syringe. The liquid thus passes through and is filtered by the filter 32 as it is aspirated or drawn through the needle. The debris 48 or shards of glass are thus removed from the liquid as it is delivered to the syringe.
In accordance with the invention, filter needle 10 is changed in use. Initially the intact filter needle 10 shown in FIGS. 1 and 2 is used to aspirate liquid through the filter and into the syringe. Thereafter, the filter needle is broken along the deformation 34, leaving a remaining portion with a fresh sharp end and a severed portion which is discarded as discussed hereinafter. The deformation allows the needle to break and form the fresh sharp end, which is used to administer the aspirated liquid or drug to a patient or into an IV line.
In this connection attention is directed to FIGS. 3-5. The needle 10, having been used to filter the liquid as it is aspirated into the syringe, is enclosed by a flexible, resilient cover 50 which has an open end 52 which is snugly fit over the outer surface 54 of luer lock 26. The cover 50 has a closed end 56 and a hollow interior chamber 60. The cover has a length sufficient to enclose the needle 10 therein as shown. The cover may be a suitable polymeric material which is flexible, resilient and sufficiently thick to protect the user from a dangerous stick.
As shown in FIG. 4, after the needle is covered as shown in FIG. 3, a shearing force Fs is applied to the cover 50 on either side of the deformation 34. Typically, the user may place thumbs on the cover in opposition to the deformation and place the index finger of each hand on the cover adjacent the deformation. The frangible deformation around the circumference of the needle is thus configured to fracture with a predefined pressure.
The opposing shear forces of the thumbs applied to the cover behind the deformation, and the force of the index fingers placed on the cover adjacent each side of the deformation creates the cover to bend and to transfer to the shaft a shear stress along the deformation causing the shaft to fail or break in such a way that there is formed a broken off tip portion 62 trapped in the closed cover and a remaining portion 64 having a fresh sharp end 66 formed along the break and a new outlet 68.
The cover 50 acts to transfer shear forces to the needle shaft and to protect the user during the step of applying stress forces on the deformation. After the needle is broken, the cover with the broken off tip 60 located there in are removed from the syringe barrel, and they may be immediately discarded or discarded later. In this way, contaminants, such as glass shards trapped in the filter may be removed from the field. The remaining portion 64 of the needle 10 with the fresh point 66 is then available for use in dispensing uncontaminated drug from the syringe by piercing an IV bag or line.
The drug is dispensed from the syringe through the inlet 64 the channel and through the fresh sharp end 66 and newly formed outlet 68. When the drug is dispensed, the syringe and remaining portion 64 of the needle may be discarded along with the cover and broken end of the needle. The cover, because it is resilient generally recovers its original shape and it and the broken off portion of the needle trapped therein, may be reinstalled over the needle and the entire assembly may be discarded in a safe manner as a unit.
Patent Application
20080097353
