HK1089398B - Catheter connector with pivot lever spring latch - Google Patents

Description

Catheter connector with pivoting lever spring latch

Technical Field

The present invention is in the field of catheter connectors, wherein a catheter connector is attached to the proximal end of a catheter.

Background

Many catheters, including but not limited to epidural catheters, need to be connected to a catheter connector located near an insertion site on a patient. Such a connector provides for neither axial nor lateral movement of the proximal end of the catheter and often includes one or more fluid connections for communicating fluid into or from the catheter.

It is important for surgeons and other medical personnel to be able to quickly, easily and reliably make such a connection of the connector to the proximal end of the catheter. It is also desirable that the connectors be relatively inexpensive if possible, as these tend to be disposable, non-reusable devices, which add to the already expensive cost of invasive medical procedures.

The goals of reliable, quick, easy, and economical connection often incur design features that conflict with one another. In terms of a reliable connection that resists axial or lateral movement of the catheter, prior art devices typically apply inward radial pressure to one or more outer surface regions of the catheter; however, excessive pressure will collapse the soft tubular conduit and at least partially close the internal fluid passage, while insufficient pressure will not reliably hold the conduit.

This connection necessarily requires manipulation by the user's hand and fingers. In this way, even if the user is able to apply the desired amount of compression to the catheter in one operation, this does not necessarily occur in the next operation. For the users of these devices, it is most difficult to always select an appropriate grip strength in many different medical surgical situations and within a very limited time of judgment.

In addition to the above-described purpose of reliably joining the catheters, the process of joining needs to be easy and quick. The time for a doctor or nurse to adjust and/or study such devices is short.

Many prior art devices apply an inward radial force on the catheter by simply pressing inward with a rigid member of the connector. The force is applied to a specific outer region or circumferentially around the catheter by a compressible collar surrounding the catheter. In the latter case, a compressible collar is coaxially located within a mating sleeve that engages a pair of threads. When the sleeves are screwed together, they exert an axial force on the collar, which then deforms radially inward against the catheter. Such rotation of the sleeves relative to each other requires the use of both hands by the operator. This two-handed operation requires time and coordination, and as discussed above, it is unlikely that the user will apply the same force each time. One of the many prior art catheter connector devices that use a threaded member to deform a plug through which a catheter extends, U.S. patent 5,464,400 to Collins, shows a male and female coupling member that axially compresses a hexagonal core member. As with other threaded connections, it requires two-handed operation; there is no idea of operating such a device with one hand, nor is there any idea of designing any device for this operation.

Another typical prior art connector structure, in which a telescoping sleeve is threaded for rotation by a two-handed operation that compresses a collar 15, is shown in U.S. patent 6,260,890 to Mason.

U.S. patent 6,228,059 to Hoffman shows yet another different locking device for a trocar in which a locking member 58 presses against a region of the sidewall of the device 34 as shown in figures 2 and 3. U.S. patent 6,096,024 to Graves et al shows a pivoting latch that engages a side wall of a needle cannula. U.S. patent No. 5,931,671 to Hoffman discloses a pair of compression elements that move laterally inward to releasably engage and retain a central tube.

This long-practiced idea of applying a lateral force to the center tube or centerpiece is clearly seen in U.S. patent 5,725,504 to Collins, wherein a simple cam lever 28 pivots to engage and deflect wall 27 against axle 12.

The long-established mode of securing a central rod (whether it be a rigid or flexible tube or rod) exhibited by the above prior art devices is: (a) using a pivoting lever to apply an inward radial force directly on the sidewall of the central rod, or (b) using a pair of threaded sleeves that can be rotated by two-handed operation to apply an axial force to a collar that in turn applies an inward radial force to a central tube.

The more widespread use of catheters and the more complex surgical procedures have led to methods that utilize some of the known elements and combine them in a new and most efficient manner. The present invention seeks to overcome all of the above-mentioned drawbacks and disadvantages of the prior art catheter connectors with a novel device that allows the connection to be applied reliably, quickly, easily and uniformly, and can be made with a single hand.

Disclosure of Invention

The new catheter connector uses a pivoting lever to generate and apply an axial force to an elastically deformable collar or plug that is closed at its outer periphery and opposite end surfaces and is deformable radially inward. Moreover, the inward force is substantially uniform all the way around the outer surface of the catheter, which reduces the likelihood of excessive localized forces collapsing the catheter. A further advantage is that the axial pressure is exerted along the length of the plug and then radially inwards, which distributes the force over a very wide surface area of the conduit. This creates a very large frictional force to grip and hold the catheter against any axial or lateral movement with minimal risk of collapse.

Furthermore, the leverage enables the user to connect with a quick and simple action and to apply the same correct force to the catheter each time. This is possible because the lever moves through the same arc and its shoulder moves the same axial distance each time.

Furthermore, such a device can be easily operated to open and close with one hand by moving a finger or thumb.

A second embodiment of the invention disclosed herein utilizes a collar or plug with a platform on the outer surface. Such a plug may be, for example, hexagonal or octagonal in cross-section, with the largest outer diameter being between two opposing points and the smallest outer diameter being between two opposing sides or flats. An alternative may be a substantially circular outer diameter with intermittent lands where the maximum outer diameter is between two opposing outer circular arc segments and the minimum outer diameter is between two opposing sides or lands. Such a plug is located substantially snugly within the circular bore of the sleeve such that it deforms radially outwardly in the region of the platform when an axial force is applied to the plug; however, the bore wall prevents further outward deformation of the plug, so further axial force deforms the plug radially inward against the conduit.

In both embodiments, the axial force applied to the tubular plug is achieved by a lever pivotally mounted on the connector housing. The lever pivots about an axis perpendicular to the central longitudinal axis of the catheter and connector, and a shoulder of the lever applies axial force to the plug or to a plunger or annular pressure member contacting the end of the plug. The lever may be pivoted by the thumb of the user while the user grips and holds the connector body with the palm and fingers thereof.

The axially compressed plug resiliently urges the lever back to its open position but a latch is provided to hold the lever in its pivoted closed position until released. The latch is formed by a protrusion on the lever and mates with a groove in the connecting body, or vice versa. In a preferred embodiment, the portion of the connecting body comprising said recess can slide axially against a spring element thereon to act to release said lever. This operation step can also be performed by one hand of the user. Upon release, the lever is pivoted to its open position as the compressed plug is connected to the lever, and the catheter is then released.

The disclosure herein shows two preferred embodiments of the lever and connector body structure with the understanding that many variations are possible.

Drawings

Fig. 1 is a top front perspective view of the novel catheter connector, with the lever in the closed position,

figure 2 is a longitudinal cross-sectional view taken along line 2-2 of figure 1,

figure 2A is an enlarged fragmentary sectional view of a portion of figure 2,

figure 3 is a cross-sectional view taken along line 3-3 of figure 1,

figure 4 is an exploded perspective view of the connector of figure 1,

fig. 5 is a top front perspective view of the novel catheter connector of fig. 1, with the lever in the open position,

figure 6 is a longitudinal cross-sectional view taken along line 6-6 of figure 5,

figure 7 is a partial cross-sectional view taken along line 7-7 of figure 1,

fig. 8 is a top plan view of a second embodiment of the novel catheter connector, with the spring latch and lever in the closed position,

figure 9 is a longitudinal cross-sectional view taken along line 9-9 of figure 8,

figure 10 is an exploded perspective view of the connector of figure 8,

FIG. 11 is a top plan view of the connector of FIG. 8 with the spring latch and lever in the open position, an

Fig. 12 is a longitudinal cross-sectional view taken along line 12-12 of fig. 11.

Detailed Description

Fig. 1-7 illustrate a first embodiment 10 of the novel catheter connector having an open position and a closed position, as will be described in detail below. The main components that can be clearly seen in fig. 1 and 4 are the connector body 12, the spring latch 14, the pivoting lever 16 with the arm 16A and the lever body 16B, the compressible elastically deformable plug 18 and the plunger 20. Fig. 10 shows another embodiment 18A of a compressible plug that is circular in cross-section. Plugs having hexagonal, octagonal and other cross-sections may be interchanged. Fig. 1 also shows a conduit 22 connected to the connector 10.

As further seen in fig. 1-7, and particularly in fig. 4, the body 12 is an elongated member having a central bore 24, a first longitudinal flange 26, a threaded proximal end 28, a recess 30 that receives the lever body 16B, a recess 32 that receives the lever arm 16A, and a recess 34 that receives the lever pivot pin 16P. Fig. 2 also shows the lever shoulder 16S abutting the stop portion 20S of the connector body 12 at a 45 ° angle α.

A general description of the operation of the device, which will be described in detail later, follows. Starting from the open position shown in fig. 4, 5 and 6, the proximal end of catheter 22 is inserted through rigid plunger 20 into compressible plug 18 already located in bore 24 of body 12. The lever arm 16A of the lever 16 is then pivoted counterclockwise until (as shown in fig. 2) its compression edge 16C applies an axial force to the left on the rigid plunger 20, which applies the axial force to the end of the compressible plug 18. The plug is generally confined within the bore 24 of the body 12 and then deformed radially inwardly against the outer peripheral portion of the conduit 22. The latch spring member will be described below as holding the lever in its closed position until released.

As shown in fig. 1-6 and 2A, the pivot pin 16P of the lever 16 is engaged in the body groove 34 (see fig. 4), the lever body 16B is engaged in the body groove 30, and the lever arm 16A is engaged in the groove 32. The lever arm 16A can be pivoted clockwise to its open position shown in fig. 2A, 5 and 6, in which the lever shoulder 16S abuts the bottom surface 20S of the plunger 20, which defines the lever such that it cannot pivot beyond the 45 angle shown.

The next major element is a compressible plug made of foam rubber or a compressible material. The plug is a tubular member having a bore sized to easily receive the conduit 22 and an outer diameter sized to easily fit into the bore 24 of the body 12. The plug has a length such that its distal end engages the plunger 20 when its proximal end abuts the proximal end of the bore 24. Since the plug 18 is defined by the bore sidewall surface and the end wall surface, axial force applied by the plunger 20 to the distal end of the plug 18 will compress the plug 18 and cause it to deform radially inwardly against the proximal end of the catheter 22.

The deformed plug will exert a radially inward force along the length of the plug, around the circumference of catheter 22, thereby snugly gripping the catheter against axial or lateral movement. The applied force will reliably engage the catheter without collapsing it and will apply substantially the same force each time, regardless of who its user is. These forces are substantially the same because each time the lever 16 is moved to its closed position, it pivots through the same arc and the plunger 20 moves the same axial distance, as shown in fig. 2, which is also controlled by a shoulder 20X on the plunger 20, which shoulder 20X is stopped by a shoulder 12X of the body 12.

As previously described, the plugs may have different cross-sections and still perform substantially the same function. Thus, the plug may be circular as shown in FIG. 10, or may have a flat as shown in FIG. 4, or may be hexagonal, octagonal, or may have other irregular shapes, so long as it deforms or compresses radially inward when it is compressed axially.

It has been experimentally demonstrated that forming the lands on the outer surface of the plug creates regions having an outer diameter that generally matches the bore or inner diameter 24 of the connector body, and intermittent regions of the outer surface of the plug having a smaller outer diameter. These latter regions will deform radially outwardly before the plug deforms radially inwardly against the conduit because these outer regions are adjacent to air spaces that do not create resistance. After this initial outward deformation, the plug is snugly defined and fixed in place, and then it will deform radially inward, generally uniformly around the engaged length and circumference of the catheter. The outer diameter of the plug may initially fit snugly within the bore, or may have a clearance.

The plug shown in fig. 4 has six evenly spaced lands, with each two adjacent lands being separated by an arcuate longitudinal region having a circular diameter that is the maximum diameter of the plug and corresponds to the bore diameter 24 of the body 12. The diameter between any two opposing lands is the minimum diameter of the plug and is the region where the major radially outward deformation of the plug will occur. The plug is preferably uniform in cross-section along its length, although the cross-section may vary along the length.

As shown in FIG. 6, plunger 20 has a proximal end to apply axial force to a substantial portion of the exposed end of plug 18, and plunger 20 has a distal end with a tapered recess to easily receive the proximal end of catheter 22 upon insertion of catheter 22. In addition, the pivoting body 16B has a diverging opening 16D as shown in FIGS. 1-2 and 4-6 to allow pivoting while the catheter extends through the opening.

The spring latching of the lever 16 is achieved as follows. As shown in fig. 1-6, the spring latch 14 is generally a cylindrical member having a longitudinal slot 40 at the top, a central recess 42 (see fig. 3), a longitudinal tooth 44 extending radially inward on both sides (see fig. 3 and 4), and a longitudinal recess 46 extending outward on both sides (see fig. 3 and 4). The member 16 also includes a spring finger 48 which can be deflected axially to the left, which then urges the latch member 14 to move to the left. As shown in fig. 4 and 5, pivot arm 16 has a latch tab 16L, the mating of latch tab 16L with latch recess 46 in latch 14 (see fig. 3 and 4) is described below.

The normal position latch 14 is to the left as viewed in fig. 1 due to the spring force exerted to the left by the latch spring finger 48. The latch can be manually moved to the right (distally) when the user grasps the latch, preferably by a ribbed surface and slides it distally to the right. When the lever arm 16A is lowered to the closed position shown in fig. 1-3, with the catheter constrained as described above, the latch 14 is spring biased to the left where its outward recess 46 receives and retains the projection 16L of the lever arm, preventing the arm from pivoting clockwise back to its open position which releases the catheter. Manually sliding the latch releases the lever arm and then the compressed plug pushes the lever to pivot to the open position. This releases the catheter quickly and automatically by simple finger or thumb action of a single hand of the user.

As shown in fig. 3, the latch 14 remains connected to the body 12 due to the fact that the longitudinal tooth 44 of the latch 14 bears against the shoulder 26 of the body 12 and slides against the shoulder of the body 12. The latch resiliently expands to slide laterally on the body 12 until the teeth 44 snap onto the shoulder 26. The latch is thus connected to the body 12 but is free to slide axially by the user.

As shown in FIG. 5, the travel distance L1 of latch 14 is greater than the length L2 of lever arm protrusion 16L, so that axial movement of latch 14 will expose and release the lever arm; however, until the latch 14 is manually released, the lever will remain securely locked.

Fig. 8-12 show a second embodiment of a catheter connector, generally similar to the first embodiment, and all elements carry the same reference numerals, except for a few differences. The first difference is that the lever pivot pin and pivot pin recess are reversed. The first embodiment in fig. 4 shows the pin 16P on the lever 16 and the pivot pin 52 of the second embodiment on the body 12 similarly, the first embodiment in fig. 4 shows the pivot pin recess 34 on the body 12 and the second embodiment in fig. 10 shows the pivot recess 50 on the lever 16.

Second, the stop or shoulder 16S of FIG. 2 is not present in the second embodiment of FIG. 12. Furthermore, the flange or shoulder 26 of the body 12 that engages the teeth 44 of the latch 14 is not present in the second embodiment of the connector of fig. 10.

The components of the novel catheter connector are made by manufacturing methods that are long known in the relevant art, and are typically injection molded plastic articles.

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

Claims (16)

1. A catheter connector operable between a first condition connected to an end of a catheter and a second condition disconnected from the catheter, comprising:

(a) a body portion including a cylindrical bore having a bore surface wall and a proximal end wall,

(b) a resiliently compressible tubular plug located in said body portion bore and having a proximal end contiguous with said proximal end wall of said body portion and an opposite distal end, said plug having a bore, said plug having a first state in which said bore can receive said end portion of said catheter and a second state in which it is deformed radially inwardly and exerts a radially inward force on said catheter after it has received said end portion of said catheter and after it has been axially compressed, and

(c) a lever mounted on said body portion and pivotable between an open position and a closed position, said lever exerting an axial force on said plug as it pivots from the open position to the closed position, whereby said plug constrained by said bore surface wall and proximal end wall of said body portion is axially compressed and radially inwardly deformed against and closely engaging said end of said catheter, and

(d) a latch arrangement operable between a locked condition and an unlocked condition, the latch arrangement including first connecting means on the body portion and second connecting means on the lever, the first connecting means being movable on the body portion to releasably engage the second connecting means when the lever is moved to the closed position, thereby urging the latch arrangement to its locked condition, the first connecting means retaining the lever in the closed position,

the body part further comprises spring means for always resiliently urging the first connecting means towards the connection with the second connecting means.

2. The catheter connector of claim 1, wherein the spring means is an integral extension from the first coupling means.

3. The catheter connector of claim 1, wherein the lever includes a first pivot member and the body portion includes a second pivot member, the first and second pivot members being coupled together for pivoting the lever.

4. The catheter connector of claim 3, wherein the first pivot element is a pin on the lever and the second pivot element is a groove in the body portion in which the pin is located.

5. The catheter connector of claim 3, wherein the first pivot element is a pin on the body portion and the second pivot element is a groove in the lever, the pin being located in the groove.

6. The catheter connector of claim 1, wherein the plug has a generally symmetrical polygonal cross-section with a plurality of flats.

7. The catheter connector of claim 6, wherein the polygon is an octagon.

8. The catheter connector of claim 6, wherein the polygon is a hexagon.

9. The catheter connector of claim 1, wherein the plug is generally circular in cross-section with a plurality of circumferentially spaced circumferential arcs with a plateau between each two adjacent arcs.

10. The catheter connector of claim 9, wherein the plug has a first diameter defined by a diameter between any two opposing lands and a second diameter defined by a diameter of the circumferential arc, the second diameter being greater than the first diameter.

11. The catheter connector of claim 1, wherein the latch has an axially deflectable finger that always pushes the latch axially to remain connected to the lever and hold the lever in its closed state until the latch is manually moved axially to release the lever for movement to its open state.

12. The catheter connector of claim 1, wherein the plug comprises rubber.

13. The catheter connector of claim 1, wherein the plug applies an inward radial force substantially equally at the proximal end around the circumference of the catheter.

14. A catheter connector operable between a first condition connected to an end of a catheter and a second condition disconnected from the catheter, comprising:

(a) a body portion including a cylindrical bore having a bore surface wall and a proximal end wall,

(b) a resiliently compressible tubular plug located in said body portion bore and having a proximal end contiguous with said proximal end wall of said body portion and an opposite distal end, said plug having a bore, said plug having a first state in which said bore can receive said end portion of said catheter and a second state in which it is deformed radially inwardly and exerts a radially inward force on said catheter after it has received said end portion of said catheter and after it has been axially compressed, and

(c) a lever mounted on said body portion and pivotable between an open position and a closed position, said lever exerting an axial force on said plug as it pivots from the open position to the closed position, whereby the plug constrained by said bore surface wall and proximal end wall of said body portion is compressed axially and deformed radially inwardly against and into tight engagement with said end of said catheter, and

(d) a latch arrangement operable between a locked condition and an unlocked condition, the latch arrangement including first attachment means on the body portion and second attachment means on the lever, the first attachment means being movable on the body portion to releasably attach the second attachment means when the lever is in its closed position, thereby to urge the latch arrangement to its locked condition, the first attachment means releasably retaining the lever in the closed position,

wherein said body portion has a central longitudinal axis, said lever has a central longitudinal axis substantially perpendicular to said body portion central longitudinal axis, said second attachment means on said lever comprises a tab extending laterally outwardly from said central longitudinal axis of said lever on each side, and said first attachment means has a slot on each side into which one of said tabs extends.

15. A catheter connector operable between a first condition connected to an end of a catheter and a second condition disconnected from the catheter, comprising:

(a) a body portion including a cylindrical bore having a bore surface wall and a proximal end wall,

(b) a resiliently compressible tubular plug located in said body portion bore and having a proximal end contiguous with said proximal end wall of said body portion and an opposite distal end, said plug having a bore, said plug having a first state in which said bore can receive said end portion of said catheter and a second state in which it is deformed radially inwardly and exerts a radially inward force on said catheter after it has received said end portion of said catheter and after it has been axially compressed, and

(c) a lever mounted on said body portion and pivotable between an open position and a closed position, said lever exerting an axial force on said plug as it pivots from the open position to the closed position, whereby said plug constrained by said bore surface wall and proximal end wall of said body portion is axially compressed and radially inwardly deformed against and closely engaging said end of said catheter, and

(d) a latch arrangement operable between a locked condition and an unlocked condition, the latch arrangement including first connecting means on the body portion and second connecting means on the lever, the first connecting means being axially slidable on the body portion when the lever is in its closed position to releasably engage the second connecting means thereby urging the latch arrangement to its locked condition, the first connecting means retaining the lever in the closed position,

wherein the first connecting means has a radially inwardly extending projection and the body portion has a shoulder adapted to resiliently engage the projection to retain the first connecting means in connection with the body portion.

16. A catheter connector operable between a first condition connected to an end of a catheter and a second condition disconnected from the catheter, comprising:

(a) a body portion including a cylindrical bore having a bore surface wall and a proximal end wall,

(b) a resiliently compressible tubular plug located in said body portion bore and having a proximal end contiguous with said proximal end wall of said body portion and an opposite distal end, said plug having a bore, said plug having a first state in which said bore can receive said end portion of said catheter and a second state in which it is deformed radially inwardly and exerts a radially inward force on said catheter after it has received said end portion of said catheter and after it has been axially compressed, and

(c) a lever mounted on said body portion and pivotable between an open position and a closed position, said lever exerting an axial force on said plug as it pivots from the open position to the closed position, whereby said plug constrained by said bore surface wall and proximal end wall of said body portion is axially compressed and radially inwardly deformed against and closely engaging said end of said catheter, and

(d) a latching device operative in: (a) the latch means holds the lever in a locked condition in its closed position, and (b) the latch means releases the lever to move it to an unlocked condition in its open position, wherein upon release of the lever by the latch means, the lever is urged by the compressed plug to move to its open position.