WO1999015221A1

WO1999015221A1 - Catheter wings with downward dihedral angle

Info

Publication number: WO1999015221A1
Application number: PCT/US1998/016913
Authority: WO
Inventors: Timothy J. Erskine
Original assignee: Becton Dickinson And Company
Priority date: 1997-09-23
Filing date: 1998-08-14
Publication date: 1999-04-01
Also published as: AU8829798A

Abstract

A catheter wing configuration is disclosed for use in securing a catheter to a curved surface of a patient's body. A pair of catheter wings extend outward from either side of the catheter and are sloped downward so as to be set at a dihedral angle with respect to the catheter. A concavity is thus defined by the bottom sides of the pair of catheter wings that allows the catheter to conform closely to the curved body surface and therefore to be fastened to the curved body surface more securely and comfortably than with conventional catheter wings. In one embodiment, each of the catheter wings slopes downward with respect to the catheter while extending substantially linearly outward from the catheter. In a further embodiment, the catheter wings initially extend directly away from each other and then bend downward at an elbow located at an intermediate point in each of the catheter wings. The catheter wings of the present invention can also be configured with a changing or constant curvature along all or a portion of their length that also imparts a downward slope to the catheter wings.

Description

CATHETER WINGS

WITH DOWNWARD DIHEDRAL ANGLE

BACKGROUND OF THE INVENTION

1. The Field of the Invention

The present invention relates to catheters for fluid communication with blood vessels or organs of the human body. More specifically, the present invention relates to catheter wings which are used for fastening a catheter to a patient.

2. The Relevant Technology

During medical treatment, fluid substances such as medications or blood are often required to be administered to the patient. The most effective manner of so doing is to deposit the fluid substance directly into the patient's blood stream where the circulatory system quickly directs the substance to the target tissue or organ. Administering a fluid substance directly into a patient's blood stream is often accomplished by injection with a conventional needle and syringe. During the course of treatment, however, a patient will often require repeated or continuous doses of a fluid substance. It will be appreciated that repeated injections with conventional syringes can damage blood vessels and cause significant discomfort to the patient.

Therefore, to administer repeated doses of fluid substances to a patient, a catheter such as the peripheral intravenous catheter shown in Figure 1 is typically used. Shown in Figure 1 is a catheter assembly 10 which includes a catheter 12, an insertion device 14, and an external connection tube 16. Insertion device 14 is used for inserting catheter 12 into a vein or organ of the patient, after which insertion device 14 is removed and external connection tube 16 is attached to catheter 12. The fluid substance to be administered to the patient then flows from a medication container through external connection tube 16, through a lumen 18 in catheter 12, and into the patient's blood stream. Thus, a continuous supply of fluid substances can be administered to the patient without the need for repeated injections using conventional needles and syringes.

Catheter assembly 10 as depicted in Figure 1 is a common catheter-over-needle configuration in which catheter 12 comprises a hollow tubular cannula 20 connected to a catheter hub 22 and containing lumen 18 therein. Catheter hub 22 and cannula 20 are usually constructed from a single mold such that lumen 18 extends uninterrupted through catheter hub 22 and cannula 20. When catheter 12 is in use, cannula 20 is partially inserted into the patient's blood vessel or organ while catheter hub 22 remains outside where it can be accessed by medical personnel. Catheter hub 22 is typically provided with a connector such as a female luer lock connector 24 for connection with an access device. One such access device is an external connection tube 16. As shown in Figure 1, external connection tube 16 is provided with a complementary male luer lock connector 32 for connection to female luer lock connector 24.

Insertion device 14 generally comprises an insertion hub 26 to which is attached an introducer needle 28. Insertion hub 26 is used to grip insertion device 14 during catheter insertion. Introducer needle 28 has a pointed distal tip 30 and is used to pierce the patient's skin and access the blood vessel or organ. Cannula 20 is a part of catheter 12 and fits over introducer needle 28, which initially resides within lumen 18. Catheter 12 can be held in place on insertion device 14 by friction engagement or can be connected with the use of male luer lock connector 25. The length of introducer needle 28 and cannula 20 are such that the tip of introducer needle 28 extends beyond the end of cannula 20 when insertion device 14 is located within catheter 12.

In use, a clinician, while gripping insertion hub 26, pierces the patient's skin with introducer needle 28 and locates the patient's blood vessel. Once introducer needle 28 is inserted into the patient's blood vessel, the clinician inserts cannula 20, which has a tapered distal portion 21, into the patient's blood vessel by sliding cannula 20 along introducer needle 28 until the desired length of cannula 20 is within the patient's blood vessel. While holding catheter hub 22, introducer needle 28 is removed by slowly pulling back on insertion hub 26, leaving cannula 20 within the patient's blood vessel. External connection unitlό is then typically attached to catheter 12 with the use of male luer lock connector 32 and female luer lock connector 24. An uninterrupted supply of medication or other fluid substances is thereafter flowed from the medication container through external connection unit 16 and lumen 18 and into the patient's bloodstream.

Typically, before connecting to external connection tube 16, catheter 12 is secured to a body surface of the patient. Failing to do so can result in catheter 12 being inadvertently removed from the patient's blood vessel, and can also result in injury to the patient. The conventional manner of securing catheter 12 to the patient's body surface is with the use of a pair of catheter wings 36 which are attached to catheter hub 22. As shown in Figure 1, conventional catheter wings 36 typically protrude straight out from the sides or bottom of catheter hub 22 directly away from each other, extending from a proximal end 38 attached to catheter hub 22 to a distal end 40. Catheter wings 36 typically comprise an elongated surface which is usually flattened at the top and bottom thereof. The flattened surfaces allow catheter wings 36 to be secured to a body surface of a patient with the use of tape or with sutures fastened through a hole 42 therein.

Catheter wings 36 are most often made of a semi-rigid hardened plastic such as polyethylene or a flexible plastic such as polyvinyl chloride. In some instances, catheter wings 36 are designed to be bent upward around catheter hub 22 for using in gripping insertion needle 28 or to provide a grasping surface on catheter 12 during insertion.

Catheter 12 of Figure 1 is only a representative example of one of the many differing types of catheters that are conventionally fastened to a body surface of a patient with the use of two outward extending surfaces such as catheter wings 36. Other examples of devices with which catheter wings 36 are typically used include centrally inserted central catheter junctions, peripherally inserted central catheter (PICC) junctions, and gastrointestinal catheters.

Conventional methods of employing catheter wings 36, while functioning reasonably well for their intended purpose, nevertheless have certain shortcomings. One shortcoming is that conventional catheter wings 36 typically extend straight outward from catheter hub 22 and thus must be physically bent downward in order to adhere to a curved body surface. The majority of the surfaces of the human body are domed, rounded, or otherwise curved in some manner. An upward pressure is exerted by the physically and unnaturally bent catheter wings 36 of the prior art against the tape or sutures used for fastening catheter wings 36 to the patient. This can lead to the clearly undesirable effects of making catheter 12 uncomfortable to the patient and making it easier for catheter 12 to come unfastened from the patient.

Accordingly, a need exists for an improved manner of fastening a catheter to the various curved body surfaces of a patient. More particularly, an improvement is needed in the conventional manner of fastening a catheter to a curved body surface of a patient, such that the catheter closely conforms to and can be securely fastened to the curved body surface of the patient, and is comfortable to the patient when so fastened.

BRIEF SUMMARY OF THE INVENTION

The present invention comprises an improved manner of fastening a catheter to a human body. More specifically, the present invention comprises a configuration of catheter wings on a catheter that allows the catheter to be fastened securely and comfortably to a human body. Under the present invention, a pair of surfaces in the form of catheter wings protrude outward from and slope downward from two opposing sides of a catheter. At least one point each of the catheter wings is thus set at a generally dihedral angle to the catheter. A concavity is formed by the bottom surfaces of the catheter wings, allowing the catheter wings to closely conform to a curved body surface.

In one embodiment, a pair of catheter wings are each attached to opposing sides of a catheter, each being set at a downward slope to the catheter and extending substantially linearly from a proximal end to a distal end. The initial downward slope of each catheter wing causes substantially every point of the catheter wings to be set at a generally dihedral angle relative to the catheter and causes a concavity to be formed by the bottom sides of the catheter wings. In a further embodiment, the catheter wings extend from a proximal end straight outward and directly away from each other for a selected distance until forming an elbow at which point the catheter wings slope downward and extend to a distal end. Thus, a dihedral angle is formed between the distal portions of the catheter wings, and a concavity is formed by the bottom side of the catheter wings. In yet another embodiment, the catheter wings are formed with a changing or continuous downward curvature that also forms a concavity and sets the tips of the catheter wings at a dihedral angle to the catheter.

The downward-sloped catheter wings of the present invention can be formed of flexible or inflexible material, can be hard or soft, and can be of any shape, though a smooth bottom surface of each catheter wing is preferred for better conformity to body surfaces. The downward sloped catheter wings as presently contemplated are suitable for use with any type of catheter. For instance, the downward-sloped catheter wing configuration of the present invention can be used with central intravenous catheters, PICC junctions, and gastrointestinal catheters.

These and other objects, features, and advantages of the present invention will become more fully apparent from the following description and appended claims, or may be learned by the practice of the invention as set forth hereinafter. BRIEF DESCRIPTION OF THE DRAWINGS

In order that the manner in which the above-recited and other advantages and objects of the invention are obtained will be readily understood, a more particular description of the invention briefly described above will be rendered by reference to specific embodiments thereof which are illustrated in the appended drawings. Understanding that these drawings depict only typical embodiments of the invention and are not therefore to be considered to be limiting of its scope, the invention will be described and explained with additional specificity and detail through the use of the accompanying drawings in which:

Figure 1 is a top view of a catheter illustrating a conventional set of catheter wings protruding straight outward from the catheter and directly away from each other.

Figure 2 is a perspective view of a catheter having a set of catheter wings configured in accordance with one embodiment of the present invention.

Figure 3 is a front view of the catheter and catheter wings of Figure 2.

Figure 4 is a front view of a catheter having thereon a set of catheter wings configured in accordance with a further embodiment of the present invention.

Figure 5 is a front view of a catheter having thereon a set of catheter wings configured in accordance with yet another embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Shown in Figure 2 is one embodiment of the improved catheter wing configuration of the present invention. Figure 2 depicts the catheter wing configuration of the present invention being used in conjunction with a typical catheter assembly 10. Catheter assembly 10 is substantially the same as that described above in reference to Figure 1. In summary, catheter assembly 10 comprises a catheter 12 formed by a hollow tubular cannula 20 and an interconnected catheter hub 22. An insertion device 14 is also provided and generally comprises an insertion hub 26 and an introducer needle 28 attached thereto. Insertion hub 26 allows the operator to grip insertion device 14 during catheter insertion. Introducer needle 28 has a pointed distal tip 30 that is used to pierce the patient's skin in accessing the blood vessel or organ. Cannula 20 of catheter 12 fits over introducer needle 28 during insertion, and is of a selected length such that the tip of introducer needle 28 typically extends beyond the end of cannula 20 when insertion device 14 is located within catheter 12.

In use, the clinician pierces the patient's skin with introducer needle 28, locates the patient's blood vessel, and then inserts introducer needle 28 into the patient's blood vessel. Cannula 20, which has a tapered distal portion 21, is also inserted into the patient's blood vessel by sliding cannula 20 along introducer needle 28 until the desired length of cannula 20 is within the blood vessel. Introducer needle 28 is then removed by slowly pulling back on insertion device 14 using insertion hub 26, and leaving cannula 20 within the patient's blood vessel. An external connection unit 16 can then be attached to catheter 12 with the use of a male luer lock connector 32 located thereon and a female luer lock connector 24 located on a proximal end of hub 22. Of course, this procedure varies for different types of catheters and for different applications in which catheters are used, and is given by way of example only. One common step in catheter insertion procedures is to secure catheter 12 to a body surface of the patient after cannula 20 has been located within the patient's blood vessel. As previously discussed, catheter 12 is typically secured to the patient with the use of a pair of catheter wings 44 extending outwardly from hub 22.

Under the present invention, the configuration of catheter wings 44 as shown in Figures 2 and 3 varies from the configuration of catheter wings 36 of Figure 1. Catheter wings 44 of the present invention comprise a pair of laterally extending surfaces that, in the depicted embodiment of Figures 2 and 3, are flat on the bottom sides thereof. Under the present invention, catheter wings 44 are sloped downwardly to closely conform to a curved surface of a human body on which catheter 12 is intended to rest. As defined herein, the terms "slope downward," "slopes downward," "sloping downward," and downward-sloped" are intended to mean that, when catheter 12 is placed on a body surface in its intended manner of operation, catheter wings 44, rather than protruding directly away from each other, are slanted down toward the body surface on which catheter 44 is resting, thereby forming a concavity to better accommodate curved body surfaces.

Figure 3 is a front view of catheter assembly 10 showing more clearly the manner in which catheter wings 44 are sloped downward. As seen therein, each of catheter wings 44 is connected to catheter hub 22 at a proximal portion 46 and extends downward to a distal end 48, such that catheter wings 44 are set at a generally dihedral angle to catheter 12.

A dihedral angle, as used herein, is the divergence of a pair of surfaces such as catheter wings 44 from a fully horizontal arrangement in which catheter wings 44 extend directly away from each other. The fully horizontal arrangement is represented in Figure 3 with dashed lines and the dihedral angle is indicated as <sr. The dihedral angle is quantified in degrees by calculating the angle between the catheter wings and the horizontal plane that passes through the origins of the catheter wings and extends outward to the locations 45 that the tips of the catheter wings would occupy if the catheter wings extended directly away from each other in the fully horizontal arrangement as indicated. Preferably, the dihedral angle at which catheter wings 44 are set in with respect to catheter 12 is in a range from between about 3 to about 45 degrees. More preferably, the dihedral angle of catheter wings 44 is in a range from between about 5 degrees to about 30 degrees. Most preferably, the dihedral angle of catheter wings 44 is in a range from between about 10 degrees to about 20 degrees. Thus, as can be seen from Figure 3, a concavity is formed by the bottom sides of catheter wings 44. The concavity formed by catheter wings 44 allows catheter wings 44 to rest securely and comfortably on a domed, rounded, or otherwise curved surface of a human body.

Catheter wings 44, as depicted in Figure 3, extend linearly between proximal end 46 and distal end 48. Nevertheless, catheter wings 44 with bends or curvatures along length thereof are also contemplated within the present invention if the general effect is a downward slope of catheter wings 44 and a concavity defined by the bottom side of catheter wings 44.

Figure 4 shows such a manner of sloping a pair of catheter wings 50 downward under the present invention. In the embodiment of Figure 4, a proximal portion 52 of catheter wings 50 is connected to catheter hub 22. Catheter wings 50 extend outward from catheter hub 22 directly away from each other until forming an elbow 60 where catheter wings 50 bend downward. Catheter wings 50 extend straight from elbow 60 to a distal end 54. Thus, the tips of catheter wings 50 are set at a dihedral angle relative to catheter 12. A concavity is thereby defined by the bottom sides of catheter wings 50, allowing catheter wings 50 to rest securely and comfortably on a curved body surface.

Figure 5 shows yet another configuration of a pair of downward sloping catheter wings 62. As shown therein, each of catheter wings 62 has a proximal end 64 originating at catheter hub 22 and curving downward therefrom with a constantly sloping curvature until terminating at a distal end 66. Thus, catheter wings 62 slope downward and the tips of each of catheter wings 62 are set at a dihedral angle relative to catheter 12. This allows catheter wings 62, as with the previously discussed embodiments, to rest securely and comfortably on a curved body surface. Of course, the curvature of catheter wings 62 need not be constant, and could be alternately curving and straight or could curve with differing degrees of slope. While the catheter wing configuration of the present invention has been discussed in conjunction with a peripheral intravenous catheter in a needle-over-catheter configuration, this application of the present invention is given by way of example only, and it will be readily apparent to one skilled in the art that the present invention can be used with any type of catheter that is intended to be fastened to a curved surface of a human body. Other types of catheters with which the present invention can be used include, by way of example and not limitation, central intravenous catheters, centrally inserted or peripherally inserted catheter junctions, and gastrointestinal catheters.

From the foregoing discussion, it will be appreciated that the improved catheter wing configuration of the present invention, in the embodiments disclosed, overcomes several long-standing problems in the art. Specifically, the catheter wing configuration of the present invention conforms more closely to a sloped body surface of a patient than the prior art catheter wing configuration in which the catheter wings protrude straight out and directly away from each other and must be bent downward in order to be fastened to a sloping surface. Catheters provided with the catheter wing configuration of the present invention can be more securely fastened to a sloped body surface and are more comfortable to the patient.

The present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative and not restrictive. The scope of the invention is, therefore, indicated by the appended claims rather than by the foregoing description. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope.

Claims

What is claimed and desired to be secured by United States Letters Patent is:

1. A medical access device adapted to be fastened to a curved body surface of a patient, comprising: a. a catheter for fluid communication with a patient; and b. a pair of surfaces protruding outward from the catheter, one to either side of the catheter, at least one point on each of the pair of surfaces being set at a dihedral angle with respect to the catheter, such that the pair of surfaces slope downward and the pair of surfaces define a concavity.

2. A medical access device as recited in Claim 1 , wherein the pair of surfaces comprise wing members.

3. A medical access device as recited in Claim 1, wherein the catheter comprises one of a central intravenous catheter and a peripheral intravenous catheter.

4. A medical access device as recited in Claim 1, wherein the medical access device comprises one of a peripherally inserted central catheter junction and a centrally inserted central catheter junction.

5. a medical access device as recited in Claim 1, wherein the medical access device comprises a gastrointestinal catheter.

6. A medical access device as recited in Claim 1, wherein the pair of surfaces comprise a top side and a bottom side and wherein the bottom sides of the pair of surfaces are substantially flat in at least one dimension.

7. A medical access device as recited in Claim 1 , wherein the dihedral angle is in a range from between about 2 to about 45 degrees.

8. A medical access device as recited in Claim 1, wherein the dihedral angle is a range from between about 5 to about 30 degrees.

9. A medical access device as recited in Claim 1, wherein the dihedral angle is in a range from between about 10 to about 20 degrees.

10. A medical access device as recited in Claim 1, wherein each of the pair of surfaces slopes downward with respect to the catheter while extending outward from the catheter substantially linearly between a proximal end and a distal end.

11. A medical access device as recited in Claim 1 , wherein at least one of the pair of surfaces has a curvature along its length, such that at least one point on each of the pair of surfaces slopes downward with respect to the catheter.

12. A medical access device as recited in Claim 1, wherein the pair of surfaces are joined together at the bottom of the catheter.

13. A medical access device as recited in Claim 1, wherein each of the pair of surfaces is affixed to an opposing side of the catheter.

14. A medical access device as recited in Claim 1, wherein each of the pair of surfaces protrudes outward from the catheter, initially substantially directly away from the other, and further comprising a curvature along the length of at least one of the pair of surfaces, causing at least one of the pair of surfaces to slope downward.

15. A medical access device adapted to be fastened to a curved body surface of a patient, comprising: a. a catheter for fluid communication with a patient's body; and b. a pair of wing members protruding outward from the catheter, one to either side of the catheter, at least one point on each of the wing members being set at a dihedral angle in a range from about 5 degrees to about 30 degrees with respect to the catheter, such that the wing members slope downward and the wing members define a concavity.

16. A medical access device as recited in Claim 15, wherein each of the wing members have a top side and a bottom side and wherein the bottom sides of the wing members are substantially flat in at least one dimension.

17. A medical access device as recited in Claim 15, wherein each of the pair of wing members slopes downward with respect to the catheter while extending outward from the catheter substantially linearly between a proximal end and a distal end.

18. A medical access device as recited in Claim 15, wherein at least one of the pair of wing members has a curvature along its length, such that at least one point on each of the pair of wing members slopes downward with respect to the catheter.

19. A medical access device as recited in Claim 15, wherein each of the pair of wing members protrudes outward from the catheter, initially substantially directly away from the other, and further comprising a curvature along the length of at least one of the pair of wing members, causing at least one of the pair of wing members to slope downward.

20. A medical access device adapted to be fastened to a curved body surface of a patient, comprising: a. a catheter for fluid communication with a patient's body, the catheter having a cannula at a proximal end for insertion into the body and having a hub at a distal end and a lumen extending through the hub and the cannula from the proximal end to the distal end; and b. a pair of wing members connected to and protruding outward from the exterior of the hub, one to either side of the hub, at least one point on each of the pair of surfaces being set at a dihedral angle in a range from about 10 degrees to about 20 degrees with respect to the catheter, such that the pair of wing members slope downward and the bottom sides of the wing members define a concavity.