WO1998048870A1

WO1998048870A1 - Dual radial tip for an insertion device

Info

Publication number: WO1998048870A1
Application number: PCT/US1998/008385
Authority: WO
Inventors: Thomas L. Spinks; Kevin H. Pike
Original assignee: Vadus, Inc.
Priority date: 1997-04-29
Filing date: 1998-04-24
Publication date: 1998-11-05
Also published as: AU7161998A

Abstract

This invention is an insertion device such as a catheter (10) having a tube (12) including a tip (18). The tip (18) is defined by a first predetermined radius and a second predetermined radius, the first predetermined radius being greater than said second predetermined radius. The device provides a dual radius tip that allows for the smooth and efficient insertion of the catheter (10) into bodily tissue.

Description

DUAL RADIAL TIP FOR AN INSERTION DEVICE BACKGROUND OF THE INVENTION

The present invention relates to a tip for an insertion device. More specifically, the

invention is directed to a dual radial tip for an insertion device, such as a catheter.

A catheter is usually inserted through the skin of a patient by use of a sharp

instrument, such as a needle. The needle extends through the catheter wherein the point of

the needle is adjacent the tip of the catheter. The needle pierces the skin of the patient to

form an opening and the tip of the catheter follows the needle into the opening. In the past,

catheter tips were blunt. The bluntness of the tips impeded the forward progress of the

catheter into the opening in the skin. The force required to insert the catheter tip into the

opening in the skin, which is also known as "transition force," was high for catheters having

blunt ends. The high transition force causes pain to the patient.

Attempts have been made to reduce the transition force required to insert a catheter

into the skin of a patient. An example of such a catheter is shown in U.S. Patent No.

4,588,398. In this patent, the tip of the catheter is angular.

It has been found that there is a need for a catheter tip that provides for the smooth

and easy transition from a needle to a catheter to reduce the transition force during insertion

of a catheter into a patient. The present invention satisfies this need.

SUMMARY OF THE INVENTION

The present invention is directed to an insertion device, such as a catheter, including a

tip having a substantially radial configuration. The tip is defined by a first predetermined radius and a second predetermined radius. The first predetermined radius is greater than the

second predetermined radius.

It is the primary object of the present invention to provide an insertion device that

reduces the transition force required to insert the device into the skin of a patient.

Other objects and advantages of the present invention shall become apparent to those

skilled in the art upon a review of the following detailed description of the preferred

embodiments and the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 is a plan view of the insertion device according to the present invention

positioned on a handle assembly with a needle extending through the insertion device;

Fig. 2 is a detailed cross-sectional view taken through the center of a first embodiment

insertion device according to the present invention;

Fig. 3 is a detailed view as shown in Fig. 2;

Fig. 4 is a detailed cross-sectional view taken through the center of a second

embodiment device according to the present invention;

Fig. 5 is a detailed cross-sectional view taken through the center of a third

embodiment device according to the present invention;

Fig. 6 is a detailed cross-sectional view taken through the center of a fourth

embodiment device according to the present invention;

Fig. 7 is a detailed cross-sectional view taken through the center of a fifth

embodiment device according to the present invention; Fig. 8 is a detailed cross-sectional view taken through the center of a sixth

embodiment device according to the present invention;

Fig. 9 is a detailed cross-sectional view of a device according to the present invention

showing the first and second predetermined radii of the tip; and

Fig. 10 is a detailed cross-sectional view of the tip of the device according to the

present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The preferred embodiments and best mode of the present invention will now be

described in detail with reference being made to the drawings. The insertion device such as a

catheter is indicated generally in the drawings by the reference number. "10"

Referring to Figs. 1-3, the catheter 10 includes a longitudinally extending tube 12

having a first end 14 and a second end 16. The second end 16 includes an attachment device

20 for attaching the catheter 10 to, for example, a handle assembly 22 or a luer (not shown).

The tube 12 includes an interior surface 24 and an exterior surface 26. The interior surface 24

is adapted to receive a needle 28 having a pointed end 30.

The catheter 10 is comprised of a plastic material. In the preferred embodiment, the

plastic material is polyurethane. It has been found that polyurethane has relatively low

coefficient of drag. This allows the catheter 10 to be inserted into the skin of a patient

smoothly and efficiently. The catheter 10 and/or the needle 28 can be treated with a

lubricant. In the preferred embodiment, the lubricant is a conventional silicone compound.

The lubricant reduces friction between the catheter 10 and the skin of a patient during

insertion. Referring to Figs. 2 and 4-8, six embodiments of the catheter 10 are shown. The

catheter 10 shown in Fig. 2 corresponds to a standard fourteen (14) gauge catheter. The

catheter 10 shown in Fig. 4 corresponds to a standard sixteen (16) gauge catheter. The

catheter 10 shown in Fig. 5 corresponds to a standard eighteen (18) gauge catheter. The

catheter 10 shown in Fig. 6 corresponds to a standard twenty (20) gauge catheter. The

catheter 10 shown in Fig. 7 corresponds to a standard twenty-two (22) gauge catheter.

Finally, the catheter 10 shown in Fig. 8 corresponds to a standard twenty-four (24) gauge

catheter.

The various dimensions of the catheters 10 shown in Figs. 2 and 4-8 are set forth in

the following table wherein the dimension A is the inside diameter of the tube 12 adjacent the

tip 18, the dimension B is the transition portion of the tube 12 adjacent the tip 18, the

dimension C is the inside diameter of the tube 12 and the dimension D is the outside diameter

of the tube 12. All dimensions are in inches (± 0.002 inch). The dimensions are important

features of the invention.

TABLE I

Referring to Figs. 9 and 10, the tip 18 of the tube 12 of the catheter 10 is defined by a

first predetermined radius R] and a second predetermined radius R₂. The first predetermined

radius R] is in the range from about RI .250 inches to about RI .750 inches and the second

predetermined radius R₂ in the range from about R0.0025 inch to about R0.0075 inch. In the

preferred embodiments, the first predetermined radius R_j is about R1.500 inches and the

second predetermined radius R₂ is about R0.005 inch.

EXAMPLE

The embodiment of the catheter 10 shown in Figs. 9 and 10 corresponds to the first

embodiment catheter shown in Fig. 2. The dimensions in Figs. 9 and 10 are set forth in the

following table wherein dimension A is the inside diameter of the tube 12 adjacent the tip 18,

the dimension B is the transition portion of the tube 12 adjacent the tip 18, the dimension C is

the inside diameter of the tube 12, the dimension D is the outside diameter of the tube 12, the

dimension E establishes the first locus 40, the dimension F establishes the second locus 42,

wherein the intersection of the first and second loci 40 and 42 establishes a first center point

44 for the first predetermined radius R the dimension G is the thickness of the tube 12

adjacent the tip 18, the dimension H establishes a third locus 46, the dimension I establishes a

fourth locus 48, wherein the inner section of the third and fourth loci 46 and 48 establishes a

second center point 50 for the second predetermined radius R₂. All of the dimensions are in

inches (± 0.002 inch). The dimensions are important features of the invention. TABLE II

It has been found that the dual radial configuration or geometry of the tip 18 allows

the catheter 10 to be smoothly and efficiently inserted into the skin of a patient with less pain

to the patient as compared to prior catheters. The dual radial tip 18 of the present invention

lowers the transition force required for insertion of the catheter 10 into the skin.

The above detailed description of the present invention is given for explanatory

purposes. It will be apparent to those skilled in the art that numerous changes and

modifications can be made without departing from the scope of the invention. Accordingly, the whole of the foregoing description is to be construed in an illustrative and not a limitative

sense, the scope of the invention being defined solely by the appended claims.

Claims

CLAIMSWe claim:

1. An insertion device, comprising:

a tube including a tip having a substantially radial configuration.

2. A catheter, comprising:

a tube having a dual radius tip.

3. A catheter, comprising:

a tube having a tip, said tip being defined by a first predetermined

radius and a second predetermined radius, said first predetermined radius being greater than

said second predetermined radius.

4. The invention of claim 3, wherein said tube includes a first end and a second

end, said tip being positioned at said first end.

5. The invention of claim 4, wherein said second end includes attachment means

for attaching said catheter to a device.

6. The invention of claim 3, wherein said tube is comprised of plastic.

7. The invention of claim 6, wherein said plastic is polyurethane.

8. The invention of claim 3, wherein said tube includes an interior surface and an

exterior surface, said interior surface being adapted to receive a needle.

9. The invention of claim 3, wherein said first predetermined radius is in the

range from about RI .250 inches to about RI .750 inches and said second predetermined radius

is in the range from about R0.0025 inch to about R0.0075 inch.

10. The invention of claim 9, wherein said first predetermined radius is about

R1.500 inches and said second predetermined radius is about R0.005 inch.