Imported: 10 Mar '17 | Published: 27 Nov '08
USPTO - Utility Patents
A clamp guard (10,110,210, . . . ) for securing to flexible tubing (50) such as catheters and their extension tubes and about a clamp (60) therealong for housing the clamp at least when the clamp is in a tubing-clamping state, to prevent inadvertent contact of the clamp by a foreign body and undesirable unclamping of the clamp. The clamp guard is removable from around the clamp when desired.
This application claims priority from U.S. Provisional Patent Application Ser. No. 60/931,917 filed May 25, 2007.
This relates to flexible tubing and more particularly to medical tubing such as catheters and their extension tubes and to clamp devices therefor.
Catheters for the introduction or removal of fluids may be located in various venous locations and cavities throughout the body for the introduction or removal of such fluids. Such catheterization may be performed by using a single catheter having multiple lumens. A typical example of a multiple lumen catheter is a dual lumen catheter in which a first lumen introduces fluids and a second lumen removes fluids. These catheters are very useful for procedures such as hemodialysis, wherein blood is removed from a patient through the first lumen for processing in a hemodialysis machine, and the processed blood is returned to the patient through the second lumen. Alternatively, multiple catheters, each having a single lumen, may be inserted in multiple locations in the patient, such as in each femoral vein.
Many such catheter assemblies are presently utilized that include extension tube assemblies at proximal ends of the lumens of multi-lumen catheters, and clamps are commonly used that allow manual actuation to clamp and unclamp the extension tubes to occlude fluid flow therethrough at selected times, such as during connection to and disconnection from tubing of hemodialysis machines. One particularly popular clamp is an in-line pinch clamp known as a Halkey-style or Roberts clamp, which has: a skeletal-like framework defining an axially extending body portion having transverse distal and proximal end portions; tube openings through its transverse distal and proximal end portions through which the tubing extends; a flexible latching arm extending proximally from the distal end portion thereof to a free end, and the transverse proximal end portion of the clamp comprising a catch arm extending to a free end upon which is defined a catch, for the latch arm free end to become latched thereto; and cooperating clamping sections that impinge on the tubing to occlude it when the clamp is in its clamping state, one clamping section being on the flexible arm and the other being defined on the axially extending body portion, both intermediate the distal and proximal ends. The latching arm is adapted to be easily manipulated by hand between latching and unlatching conditions that correspond with clamping and unclamping states of the clamp. Such a clamp would be maintained in the clamped state most of the time, that corresponds to all times other than when a practitioner is performing hemodialysis or infusion, or is withdrawing a blood sample.
Such a clamp in its latched and clamped state has a drawback in that the free end of the catch arm can snag on clothing, linens, tubing, wiring and other articles and snag and strain the tubing and the catheter, potentially harming the patient or damaging the catheter assembly. Even more problematic is that the catch arm free end can snag sufficiently to unlatch the latching arm resulting in unclamping of the clamp permitting blood to flow freely from the patient, causing great harm, especially when the patient is unattended in order for remedial action to be performed.
It is desired to provide a way of minimizing the possibility of the tubing clamp snagging or becoming inadvertently unclamped.
The present invention is directed to an article for placement about a flexible tubing clamp to guard against accidental opening thereof when in its clamped state occluding fluid flow through the flexible tubing. Preferably, the article envelopes most of the clamp to minimize any snagging by any portion of the clamp and also itself possesses a snagging-free external surface, such as by having minimal if any protrusions, and also, preferably, having rounded exposed edges and corners, which also presents an additional advantage of patient comfort.
In one embodiment, the article is a housing that is adapted to be placed along the tubing adjacent to the clamp and that has distal and proximal openings in its distal and proximal ends, with the distal opening of the housing defining a large clamp-receiving opening and being adjacent the proximal end of the clamp, while the proximal opening is sufficiently large for the tubing to pass therethrough. The housing would preferably be movable along the tubing to envelop the clamp at least when the clamp is in its clamping state at which time the flexible latch arm of the clamp is in its latched state and such that the end of the clamp at which the free end of the latching arm is disposed, is totally within the housing.
In another embodiment, the guard is a housing similar to that described above, wherein the interior of the housing is so dimensioned as to define a friction fit with the clamp wherein the housing is maintained about the clamp.
In a third embodiment, similar to those described hereinabove, the guard housing includes an opening at its relatively closed end so shaped and dimensioned for receipt thereinto of the free end of the catch of the clamp in a snap-fit, for holding the guard housing in position about the clamp.
In a fourth embodiment, the guard is a housing similar to those described hereinabove, wherein the housing is a two-part housing, the housing parts disposed about and along the flexible conduit in respective positions distally and proximally from the distal and proximal ends of the clamp, wherein the two housing parts are adapted to be secured together about the clamp.
Additional embodiments of the guard of the present invention are disclosed wherein the guard housing is positioned along the flexible conduit distally of the clamp and are translatable along the conduit to envelop the clamp from the distal end thereof, that is, the end from which the latching arm of the clamp extends. In a fifth embodiment, the guard housing defines an interior that is large enough just to receive the distal end portion of the clamp thereinto when the latching arm is in its latched state, and would define a friction fit with the clamp. While the free end of the proximal end portion of the clamp (i.e., the catch arm) would protrude from the housing and thus be exposed, the latching arm would be secured in its latched state by abutment with the guard housing even if the catch arm became inadvertently snagged.
In a sixth embodiment, similar to the fifth, the guard housing defines an interior that, at the housing end remote from the clamp-receiving opening, includes a diverging top wall of the clamp-receiving opening that creates an enlarged interior clearance area that can receive thereinto the free end of the catch arm of the clamp that would obviate any snagging of the catch arm.
A seventh embodiment of guard housing is similar to the immediately preceding embodiment, except that the end portion of the top wall does not diverge but instead protrudes beyond the proximal end of the housing and includes an overhang that defines a snap-fit with the free end of the catch arm to assure securing of the guard housing about the clamp when the clamp is fully received into the housing.
Further, the embodiments could be adapted for retrofit application by including a clip structure for being applied laterally to the length of tubing, and could also have internal latch projections to latch to the clamp's skeletal-like framework.
In the drawings, like numerals indicate like elements throughout. Certain terminology is used herein for convenience only and is not to be taken as a limitation on the present invention. Flexible tubing or conduit includes catheters and extension tubes therefore, without limitation. The terms distal and proximal refer, respectively, to directions away from and closer to the latching arrangement of the clamp. Tubing refers to flexible tubing of the type used in medical devices and includes catheters, intravenous tubing and extension tubes of catheters assemblies. The terminology includes the words specifically mentioned, derivatives thereof and words of similar import. The embodiments illustrated below are not intended to be exhaustive or to limit the invention to the precise form disclosed. These embodiments are chosen and described to best explain the principle of the invention and its application and practical use and to enable others skilled in the art to best utilize the invention.
Generally, clamp members illustrated herein are of the Roberts type, but the present invention is not restricted to only this type of clamp; modifications may be made to the indicia-bearing article of the present invention to adapt to different styles of clamps, within the skill of the artisan.
In the first embodiment shown in FIGS. 1 to 5, a first embodiment of clamp guard device 10 includes a body 12 having a pair of side walls 14,16, a top wall 18, bottom wall 20, an interior 22 and a proximal end 24 with a tube aperture 26, and distal end 28. Optionally, one or more walls of the clamp guard 10 may have indicia thereon, as indicated at 30. Also seen in FIGS. 2 to 5 is an assembly of a length of flexible tubing 50, a fitting 52 affixed to a proximal end of the tubing, and a clamp member 60 secured along the tubing 50, the clamp being manipulatable between an unclamping state and a clamping state in which fluid flow through the tubing 50 is occluded. Clamp 60 is an in-line clamp having a skeletal-like framework body 62 having a distal end 64, proximal end 66, openings 68 through the distal and proximal ends through which the tubing extends, a latch arm 70 extending from the distal end 64 proximally to a free end 72, and a catch arm 74 at the proximal end 66 extending transversely to a free end having a catch 76 that cooperates with the latch arm free end 72 when the clamp is in the latched and closed state. FIGS. 3 and 5 show the cooperating clamping sections 78,80 that impinge on the flexible tubing 50, as seen in FIG. 5, for its occlusion when the free end of the arm 70 is latched to catch 76 to hold it in the clamping state; such a clamp is conventionally known as a Roberts clamp.
Generally, with respect to all of the disclosed embodiments, the clamp guard devices may be made of soft pliable polyurethane like 80A PELLETHANE polymer (a product of Dow Chemical Co.), or silicone elastomer, or may be made of ABS, polyvinyl chloride, polypropylene or other suitable plastic materials that may alternatively produce semi-rigid or rigid properties. The clamp members may be made of similar suitable plastic materials but have substantial rigidity to maintain clamping of the flexible tubing; in-line pinching clamps are commonly made of polypropylene or acetal. The flexible tubing may be biocompatible elastomers such as silicone rubber, usually for catheters, or polyurethane, usually for extension tubing or some catheters.
Further, with respect to all embodiments, it is preferred that the exposed edges of the guard be gently rounded to minimize skin irritation of the patient, problematic especially in certain patient populations with compromised skin such as patients with diabetes. Generally speaking, the guard of the present invention would fit snuggly about the clamp, or remain in position therearound such as by latches or snap fit, protect against inadvertent and undesirably unclamping of the clamp from the tubing, and be removable therefrom when it is desired to unclamp the clamp from the tubing.
FIGS. 6 and 7 show a second embodiment of clamp guard 110 with a pair of side walls 114, 116, top and bottom walls 118, 120, a proximal end 124 with tube aperture 126, and a distal end 128. In this embodiment, guard body 112 is narrower between side walls 114, 116, enabling proximal end 124 to establish a friction fit at internal corners 132 or along interior side surfaces with upper and lower side edges of a tubing clamp such as clamp 60 of FIGS. 2 to 5, upon receipt thereof into guard interior 122 when the clamp is in its closed state as in FIG. 5. Clamp guard 110 is removable from about clamp 60 permitting access thereto for unclamping the tubing, when desired.
Clamp guard 210 of FIGS. 8 to 12 provides for a latching arrangement to secure the clamp guard about the clamp 60 in its clamping state along the flexible tubing 50. Clamp guard 210 has a distal end 228 open for receipt into its interior 222 of the clamp. A transverse opening 234 is defined at the junction of top wall 218 and proximal end 224, associated with catch arm 74 of clamp 60. As seen in FIGS. 11 and 12, when clamp 60 is in its clamping state and latch arm 70 is latched to catch arm 74, clamp guard 210 is moved along tubing 50 until clamp 60 is received into interior 222; catch arm 74 snaps into transverse opening 234 and latches behind, or proximally of, overhang 236 of top wall 218 of the clamp guard, holding the clamp guard in position about the clamped clamp in a manner permitting removal therefrom for unclamping from the tubing, when desired.
In FIGS. 13 to 16, clamp guard embodiment 310 is seen to comprise two housing parts, 312A and 312B, that self-secure to each other about the clamped clamp 60 in a manner permitting disassembly to access the clamp for unclamping when desired. Housing parts 312A and 312B each have a transverse end section 324,328 respectively each having an opening 336,326 through which the tubing extends, and each has an open opposite end 338,340 enabling receipt thereinto of ends of the clamp. Preferably, housing part 312A is disposed distally of the clamp along the tubing 50, and housing part 312B is disposed proximally of the clamp, as seen in FIGS. 15 and 16, and both housing parts are translatable along the tubing and about the clamp after which the housing parts latch to each other. As shown, the distal end 338 of housing part 312A is received into proximal end 340 of housing part 312B, and latch projections 342 at the distal end of housing part 312A latch into ends 344 of latch slots 346 along side walls of housing part 312B for latching the housing parts to each other about the clamp 60.
Another embodiment of clamp guard 410 is seen in FIGS. 17 to 20, comprising a unitary housing 412. Clamp guard 410 is disposed along the tubing distally of the clamp and is translatable proximally to receive all but the proximal end of the clamp 60 into interior 422 thereof. Clamp guard 410 is dimensioned to establish a friction fit with and about clamp 60 when in its clamping state, in a manner permitting removal therefrom for accessing the clamp for unclamping the tubing.
Clamp guard embodiment 510 of FIGS. 21 to 29 also comprises a unitary housing 512. Clamp guard 510 is similar to clamp guard 410 of FIGS. 17 to 20 except that it is adapted to latch directly onto the clamp. Clamp guard 510 is seen to provide a wide slot 548 along bottom wall 520 and continuing along distal end section 528 and opening onto distal opening 526; this permits clamp guard 510 to be secured onto the flexible tubing from laterally thereof, as seen in FIGS. 24 and 25. Within interior 522 of clamp guard 510, adjacent to distal end section 528 thereof, are a pair of opposed latch projections 542 that are shaped and dimensioned to latch proximally of the proximal inside surface of clamp distal end 64, as seen best in FIG. 28. (In FIG. 24, latch projections 542 are seen because of apertures through distal end section 528 remaining as relics from the molding process.) At the proximal end 524 of clamp guard 510, the top wall 518 includes an outwardly angled wall portion 550 that will be disposed outwardly of and over catch arm 74 of clamp 60 to inhibit snagging thereof by any foreign objects such as tubing, wires, clothing and so on that could otherwise tend to inadvertently and undesirably unclamp the clamp from the tubing.
An additional clamp guard embodiment 610 is illustrated in FIGS. 30 to 34, comprising a unitary housing 612. This embodiment is similar to clamp guard 210 of FIGS. 8 to 12, but is disposed on tubing 50 distally of clamp 60. Top wall 618 of housing 612 includes an overhang 636 at otherwise open proximal end 624 that will snap over catch arm 74 of clamp 60.
A further, eighth embodiment of clamp guard 710 is shown in FIGS. 35 to 38, wherein the clamp guard distal end includes a tubing opening 726 through the proximal wall 728, similar to the clamp guards of FIGS. 2 and 7; optionally, a slotted entrance could be provided similar to that in the clamp guard configuration of FIG. 22. Further, the embodiment lacks a bottom wall, so that it may be clipped onto the tubing and moved adjacent the distal end of the clamp and then rotated or pivoted about the clamp in its closed position. A pair of catches 742 facing each other at the bottom edges of the opposing clamp guard sidewalls, will latch onto and about the bottom edges 82 of the clamp to secure the clamp guard in position about the clamp.
In FIG. 39, a ninth embodiment of clamp guard 810 is illustrated. Clamp guard 810 has two half portions 852,854 joined to each other by a living hinge 856. A first half portion 852 includes a latch member 858 along the opposite side from the hinge, and the second half portion 854 includes a catch 860 along the opposite side from the hinge. The first and second half portions can be pivoted about living hinge 856 until latch member 858 and catch 860 latchingly engage, for clamp guard 810 to be secured about a clamp. A transverse body section 862 may be included at one end of clamp guard 810, having a tubing aperture 826 therethrough by which the clamp guard can be secured to the tubing during assembly.
Further variants of the invention include a guard of two parts latchable to each other directly around the clamp in similar fashion to the clamp guard of FIGS. 35 to 38, without self-retaining to the flexible tubing directly (not shown). It is also foreseeable that the clamp guard of the present invention may be free of one of the two side walls, or be free of a bottom wall or a distal end wall.
It will be appreciated by those skilled in the art that changes could be made to the embodiments described above without departing from the broad inventive concept thereof. It is understood, therefore, that this invention is not limited to the particular embodiments disclosed, but it is intended to cover modifications within the spirit and scope of the present invention as defined by the appended claims.