US 3082769 A
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Description (OCR text may contain errors)
March 26, 1963 D. H. PALMER 3,082,769
INTRAVENOUS NEEDLE Filed Dec. 19. 1960 FIG.1
INVENTOR. Dewey H. Palmer BY u a. W
ATTORNEY United States Patent F 3,082,769 INTRAVENOUS NEEDLE Dewey H. Palmer, Oradell, N.J., assignor to Clay-Adams, Inc., New York, N.Y., a corporation of New York Filed Dec. 19, 1960, Ser. No. 76,972 2 Claims. ((31. 128-221) This invention relates to catheters, and more particularly, concerns flexible catheters formed of elastomeric or plastic materials, such catheters being particularly adapted for use in intravenous therapy and the like.
It has been proposed to use flexible tubing of polyethylene or other suit-able plastics or elastomers, as a catheter for the introduction of various liquids including blood, nutrients or the like, into body cavities, blood vessels or the like. Various expedients have been resorted to in order to properly dispose the catheter within the body cavity or blood vessel. Thus, the catheter has been initially located internally or externally of a hollow needle whose needle point punctures the wall of the body cavity or blood vessel, thereby allowing the catheter to be threaded through the puncture opening provided by the needle.
With the catheter disposed internally of the needle, the needle is necessarily of relatively large gauge; giving rise to oversize puncture openings which are larger than the catheter and frequently causing leakage at the puncture opening unless the punctured wall has substantial elasticity.
When the catheter is disposed externally of the needle in accordance with conventional arrangements thereof, it is difiicult to thread the leading edge of the catheter into the puncture opening without either tearing the tubing edge, or causing trauma at the puncture opening, or both.
Accordingly, an object of this invention is to provide an improved combination catheter and needle for inserting the same into a punctured wall opening without tearing the edge of the introduced catheter; avoiding leakage at the puncture opening; and substantially eliminating possible trauma at the puncture opening.
Another object of this invention is to provide an im proved hollow needle for use with flexible catheters, the needle being of generally conventional form but modified for novel coaction with the associated catheter disposed externally of the needle.
A further object of this invention is to provide an improved flexbile catheter having a novel tip structure and an improved integral hub construction.
Other objects of this invention will in part be obvious and in part hereinafter pointed out.
In the drawing, FIG. 1 is a top plan view of a needle embodying the invention and adapted to carry a catheter externally thereof; FIG. 2 is a side elevational view thereof; FIG. 3 is a longitudinal view of a catheter embodying the invention, with parts in section; FIG. 4 is a partial, longitudinal sectional view of the tip portion of the needle-catheter assembly; and FIG. 5 is a similar view showing a modified form of .the needle-catheter assembly.
In accordance with the invention, there is provided as shown in FIGS. 1, 2, a needle 10. Needle comprises the usual cannula portion 11 with a conventional hub 12 at the rear end thereof. The forward end of needle 10 is bevelled as at 13 to form a sharp tip 14. The bevelled tip 14 and cannula portion 11 have a juncture at 15.
The tip end of needle 10 is radially constructed, as by .the use of dies or other metal forming means, to provide an annular constriction of groove 16. Groove 16 may be of limited longitudinal extent and tapers forwardly from point 17 to a point 18 spaced somewhat from juncture point 15. The use of constricting dies on the metal of cannula portion 11 will produce a slight annular rise of 3,082,769 Patented Mar. 26, 1963 metal immediately forward of point 18, as at 19. The groove 16 is of limited radial extent and leaves lumen 20 open throughout its axial extent. Lumen 20 is of uniform diameter with a slight reduction of diameter as at 21 opposite groove 16.
In FIG. 3 .is shown a novel catheter particularly adapted for use with needle 10 and to be disposed externally thereof. Catheter 25 is formed of polyethylene, polyvinyl copolymer, nylon or other suitable plastic or elastomeric tubing. Since the catheter is disposed exteriorly of needle 10, it is provided in lengths proportioned to the needle length.
Tubing 26 is of uniform diameter except at one end thereof, where tip 27 is in normally constricted form over a short longitudinal portion thereof. Thus, the normal inner and outer diameters of tip 27 are somewhat smaller than the corresponding inner and outer diameters of tubing 26.
Tubing 26 further comprises at the rear end thereof an integral hub portion 28 which includes an annular collar 29 and a tubular portion 30 extending rearwardly of collar 29. The bore 31 of tubular portion 30 is somewhat larger than the communicating bore 32 of tubing 26 and collar 29. Hub portion 28 allows for the connection of catheter 25 to other tubings, adapters, syringes and the like. Bore 31 may have a standard Luer taper to complement standard Luer connectors.
As shown in FIG. 4, catheter 25 is mounted on needle 10 with catheter tip 27 disposed in groove 16. Thus, the catheter tip 27 does not project outwardly of the outer diameter of cannula 11 or of the annular rise 19.
It has been found that the combination of needle 10 and overlying catheter 25 may be used to puncture the wall of a blood vessel or a body cavity by way of tip 14, followed by threading the catheter 25 forwardly over the needle 10 into the blood vessel of body cavity. The
leading edge of catheter tip 27 is protected against direct contact with the punctured wall as the needle tip 14 passes through the opening therein, thus avoiding tearing of the catheter tip 27 and materially reducing possible incidental trauma.
Thereafter, needle 10 may be retracted relative to catheter 25, leaving the catheter in place. The flexibility and elasticity of tubing 26 allows the catheter tip 27 to pass over rise 19 in needle 10, as the needle is withdrawn.
As shown in FIG. 5, catheter 25A is formed at its forward end with an annular, inwardly directed, reentrant or hook shaped tip portion 40 The needle 10A used in conjunction with catheter 25A, is formed on its tip 14A with an annular groove 41 having forwardly inclined, opposed walls 42, 43. With catheter 25A mounted on needle 10A, catheter tip 40 is received in needle groove 41.
Thus, the inturned catheter tip 40 is resistant to tearing when the needle tip 14A punctures the wall of the blood vessel or body cavity. Also, needle groove 41 facilitates the retraction of needle 10A to leave catheter 25A in place.
As various changes might be made in the embodiments of the invention herein disclosed without departing from the spirit thereof, it is understood that all matter herein disclosed shall be deemed illustrative and not limiting except as set forth in the appended claims.
What is claimed is:
1. A hollow needle including a cannula portion and a bevelled tip portion, said cannula portion comprising a narrow annular portion projecting radially outward of the outer surface of said cannula portion at a point adjacent the rear of said bevelled tip portion, said cannula portion being formed with an annular groove merging at the forward end thereof with the trailing edge of said radially projecting annular portion, said groove tapering longitudinally toward said radially projecting annular portion, said radially projecting annular portion comprising an inclined forwardly extending annular surface portion and an inclined rearwardly extending annular surface portion, said rearwardly extending annular surface portion merging at its lower edge with the forward edge of said tapered groove, said radially projecting annular portion having an outer diameter greater than the outer diameter of the cannula portion immediately forward thereof and the cannula portion immediately rearward of said annular groove.
2. A hollow needle including a cannula portion and a bevelled tip portion, said cannula portion comprising a narrow annular portion projecting radially outward of the outer surface of said cannula portion at a point adjacent the rear of said bevelled tip portion, said cannula portion being formed with an annular groove extending rearwardly from said radial annular portion, said annular 4 groove having a length greater than the radial depth of said radial annular portion, said radial annular portion having an inclined annular surface portion extending toward said bevelled tip portion and an inclined annular surface portion extending toward said groove and merging with said groove, said radial annular portion having an outer diameter greater than the outer diameter of the cannula portion immediately forward thereof and the cannula portion immediately rearward of said annular groove.