Patent Application
20100036330
This patent is directed to a needleless connector, and, in particular, to a needleless connector with a mechanism for displacement correction.
Needleless connectors have come into widespread use in intravenous (I.V.) administration sets. Needleless connectors replace more traditional technologies, wherein a needle is used to puncture an elastomeric diaphragm or septum. The use of needles and other pointed instruments presents hazards to equipment, patients and healthcare personnel. For example, accidental needle sticks may permit infectious diseases to be transferred from the patient to the healthcare worker.
However, certain needleless connectors may be subject to retrograde flow. That is, when a syringe, blunt cannula or other instrument is inserted into the connector, a volume of fluid is displaced out of the connector and associated set into the patient. This is referred to antegrade flow. However, when the instrument is withdrawn, a similar volume may be drawn into the I.V. set components or the connector from the patient. This is referred to as retrograde flow or reflux.
It is believed by some that retrograde flow can decrease the efficacy of infusion therapy. It is also believed by some that when the blood and/or other fluids flow into the associated catheter, the blood can clot in the catheter.
To oppose the retrograde flow into the connector and associated catheter, methods and devices have been devised that focus on positive displacement or positive pressure. Initially, methods were devised wherein the healthcare worker would continue to flush through a connector/catheter combination and clamp the infusion line as an instrument, a syringe, for example, was removed from the combination, with the intent that this positive pressure flush would limit retrograde flow. However, the complexities of coordination and timing increase the complexity in providing infusion therapy. Over time, devices were devised wherein a positive displacement would occur automatically within the connector when the intruding instrument was withdrawn from the connector, without the involvement of the healthcare worker. Unfortunately, the complexities of the mechanisms designed to achieve automatic positive displacement led, in certain instances, to the same issues of consistency and reliability posed by the manual positive pressure flush method. For example, positive displacement devices that relied upon a structure that bent upon insertion of an instrument into the connector could have unpredictable modes of deformation.
As set forth in more detail below, the present disclosure sets forth an improved assembly embodying advantageous alternatives to the conventional devices and methods discussed above.
In one aspect, a needleless connector includes a housing having an inlet and an outlet, a valve disposed in the housing to control flow between the inlet and the outlet, and a gland disposed in the housing between the inlet and the outlet. The gland has a deformable wall defining a space, and at least one reinforcement attached to the deformable wall within the space.
Additional aspects of the disclosure are defined by the claims of this patent.
It is believed that the disclosure will be more fully understood from the following description taken in conjunction with the accompanying drawings. Some of the figures may have been simplified by the omission of selected elements for the purpose of more clearly showing other elements. Such omissions of elements in some figures are not necessarily indicative of the presence or absence of particular elements in any of the exemplary embodiments, except as may be explicitly delineated in the corresponding written description. None of the drawings are necessarily to scale.
Although the following text sets forth a detailed description of different embodiments of the invention, it should be understood that the legal scope of the invention is defined by the words of the claims set forth at the end of this patent. The detailed description is to be construed as exemplary only and does not describe every possible embodiment of the invention since describing every possible embodiment would be impractical, if not impossible. Numerous alternative embodiments could be implemented, using either current technology or technology developed after the filing date of this patent, which would still fall within the scope of the claims defining the invention.
It should also be understood that, unless a term is expressly defined in this patent using the sentence “As used herein, the term ‘______’ is hereby defined to mean . . . ” or a similar sentence, there is no intent to limit the meaning of that term, either expressly or by implication, beyond its plain or ordinary meaning, and such term should not be interpreted to be limited in scope based on any statement made in any section of this patent (other than the language of the claims). To the extent that any term recited in the claims at the end of this patent is referred to in this patent in a manner consistent with a single meaning, that is done for sake of clarity only so as to not confuse the reader, and it is not intended that such claim term be limited, by implication or otherwise, to that single meaning. Finally, unless a claim element is defined by reciting the word “means” and a function without the recital of any structure, it is not intended that the scope of any claim element be interpreted based on the application of 35 U.S.C. §112, sixth paragraph
Embodiments of a needleless connector according to the present disclosure are discussed herein. A convention has been used where the direction towards the top of the page is generally referred to as “distal,” and the direction towards the bottom of the page is generally referred to as “proximal.” It will be recognized that use of this convention is intended to simplify reference to the features as illustrated, not to limit the features to a particular orientation in use, for example.
As seen in
As illustrated in
The inlet section 130 is attached to the outlet section 136 with the valve 112 and the gland 114 disposed therein. To this end, the inlet section 130 has a proximal end 142 with an opening 144 formed therein to accept a portion of the outlet section 136 (see
According to the embodiment illustrated, the valve 112 that controls the flow of fluids between the inlet 120 and the outlet 122 is in the form of an overmolded septum, which may be elastic and resilient and made of silicone, for example. The septum may be molded from a material having a single durometer value, or, alternatively, may be molded in layers with each layer having a different durometer value. According to other embodiments, other valve types may be used, including septums that have not been overmolded, for example. The valve illustrated in the drawings is thus intended to be illustrative and non-limiting.
The illustrated valve 112 includes a first wall 160 that is disposed across the opening 134 in the inlet section 130, and a second wall 162 that depends away from the first wall 160 along a passage 164 formed in the inlet section 130. According to the geometry of the inlet section 130, the first wall 160 is disc-shaped, while the second wall 162 is cylindrical. The first wall 160 of the septum 112 has a slit 166 (see
The first wall 160 is stretched downward into the housing 110 when an instrument is disposed into the slit 166 to seal against leakage at an interface between the instrument and the septum 112 before, during and after extension of the instrument through the slit 166. The septum 112 may be lubricated to facilitate insertion of the instrument into the septum 112, which lubrication may be applied while forming the slit 166 or by other methods such as incorporating the lubrication into the septum material or by applying lubricous coatings to an outer surface 168 of the septum 112. The slit 166 elastically retracts upon removal of the instrument.
Features may be added to the septum 112 to keep the slit 166 in compression even after the molding process is completed. That is, during the molding process, the material of the septum 112 shrinks. As a consequence, without further steps, the slit 166 will be placed in tension, causing the slit 166 to open. As illustrated in
In particular, as seen in
However, the features that improve the ability of the slit 166 to remain closed may also have an undesirable effect on the amount of force required by the user to insert an instrument, whether Luer syringe, blunt cannula, etc., into the slit 166. To reduce the force required for insertion while biasing the slit 166 closed, additional features may be added to the septum 112, which also may best be seen in
It will be recognized that it is not necessary that an embodiment of a needleless connector 100, even one using an overmolded slit septum as the valve 112, include all of the features illustrated in
Following the inlet section 130 along the passage 164 in which the overmolded slit septum 112 is disposed, the passage 164 widens in cross-sectional area as it moves along from the distal end 132 to the proximal end 142, as best seen in
Once past the transition region 210, the plurality of passages 212 converge into a single passage 224. However, unlike the passage 164 above the transition region 210, which is circular in cross-section, this passage 224 has an annular shape. In particular, the annular passage 224 is defined by a surface 226 of the inlet section 130 and an opposing surface 228 formed at the distal end 146 of the outlet section 136.
Shifting then to the distal end 146 of the outlet section 136, as seen in
The cross passage 246 connects to a passage 248 disposed along a longitudinal axis of the outlet section 136, which passage 248 has at its proximal end 250 the opening 140 that defines the outlet 122. The axial passage 248 is orthogonal to the cross passage 246, forming a T-shaped intersection, although it will be recognized that the passages 246, 248 could meet at some other angle as well. In particular, the axial passage 248 may be defined by a lumen 252 of a projection 254 from the outlet section 136.
As illustrated, the projection 254 is in the form of a Luer tip, and a skirt 256 is arranged coaxially with the projection 254, and has a threaded region 258 formed on an inner surface 260 thereof. Consequently, the illustrated embodiment may be used as a Luer lock. However, the present disclosure is not limited to an outlet section 136 with such an arrangement; this is simply one embodiment according to the present disclosure. The projection 254 may be formed as a slip Luer by omitting the threaded region 258. The connector 100 could instead be formed as the injection arm of a Y-site or Y-set or as an inlet on a stopcock or manifold, or formed integrally with a catheter. In any event, the housing 110 may have indentations that facilitate gripping of the connector 100.
Returning then to
As seen in
The space 272 defined by the deformable wall 270 is in communication with the at least one vent 124 formed in the housing 110 via the open proximal end 276. As illustrated, there are two vents 124, each vent 124 defined by a passage 280, 282 formed in the outlet section 136. It will be recognized that a greater or a lesser number of vents 124 may be included, and the vents 124 may be defined by structures other than the outlet section 136 as identified in the illustrated embodiment.
In addition, the outlet section 136 may include a trough 284 having a first end 286 and a second end 288. Each passage 280, 282 is connected to one of the first end 286 or the second end 288 of the trough 284. While a trough 284 is an optional feature, it may be an advantageous feature, in that the trough 284 provides a larger opening for access to the two passages 280, 282 that define the vents 124, thereby limiting the chances that the gland 114 will restrict access to the vents 124 to prevent escape of air from the space 272. It will also be recognized that the number of vents and their placement (i.e., two vents 124 spaced at opposite ends 286, 288 of the trough 284) assist in limiting the chances that the gland 114 will restrict access to the vents 124 to prevent escape of air from the space 272.
The gland 114 is maintained in place within the housing 110 with the proximal open end 276 in communication with the vents 124 at the distal end 146 of the outlet section 136 through cooperation of the inlet section 130, the outlet section 136, and the gland 114. As noted above, the dividers 214 that are formed in the transition region 210 of the inlet section 130 have a stepped shoulder 222. This shoulder 222 faces a surface 290 at the distal end 146 of the outlet section 136 (compare
As noted above, the gland 114 is deformable to limit retrograde flow into the connector 100. To control the deformation of the gland 114, the gland 114 has at least one reinforcement 300 attached to the deformable wall 270 within the space 272. The at least one reinforcement 300 causes the deformable wall 270 to collapse in a preferred fashion, with collapse occurring inwardly near the center of the gland 114, similar to a bellows or accordion. To this end, the distal end 274 of the cup-shaped wall 270 defines an internal shoulder 302, and the at least one reinforcement 300 is attached to the deformable wall 270 at the internal shoulder 302. As illustrated, the reinforcement 300 is a triangular tab attached across the internal shoulder 302, with a first end 304 formed integrally with a transverse surface 306 of the wall 270 and a second end 308 formed integrally with a lateral surface 310 of the wall 270.
It will be recognized that the shape and relative dimensions of the reinforcements 300 as illustrated are only one embodiment according to the present disclosure. It will also be recognized that other changes to the gland 114 may be made in conjunction with the reinforcements 300 to vary the collapsing profile and/or collapsed shape of the gland 114. For example, the height of the wall 270 may vary the collapsing profile, as may the thickness of the wall 270, which may vary between proximal and distal ends. In the alternative or in addition, the wall 270 may be molded in layers, each layer having a different durometer value, to vary the collapsing profile.
The collapsing profiles and/or collapsed shape may influence not only the displacement provided (e.g., positive, neutral or negative), but the profiles may influence the flow of fluid about the gland 114. Moreover, by varying the shape, the size or the placement of the reinforcement 300 or the height or the thickness of the wall 270, while maintaining the cross-section of the gland 114, a family of glands may be produced that permit use of the connector 100 in pediatric as well as adult settings.
The gland 114 also includes features that guide the contact between a Luer syringe, blunt cannula or other instrument and the gland 114. For example, the gland 114 includes a post 312 that depends from the wall 270 toward the septum 112, the post 312 having a proximal end 314 attached to the wall 270 and a free distal end 316. See
As illustrated, the at least one reinforcement 300 is attached to the deformable wall 270 along an axis transverse to the groove 318. In fact, as illustrated, two reinforcements 300 are shown, the two reinforcements 300 attached to the deformable wall 270 along an axis transverse to the groove 318. As is shown in the other embodiments below, this is not an exclusive orientation of the reinforcements 300 relative to the groove 318, but one such embodiment.
Where the gland 400 of
Another embodiment of a gland 450 that may be used with a needleless connector, such as is illustrated in
A still further embodiment of a gland 480 that may be used with a needleless connector, such as is illustrated in
However, unlike the embodiment illustrated in
It will be recognized that further embodiments are possible wherein the groove has geometries different than those illustrated in the embodiments described above. For example,
It will also be recognized that, according to other variants, the groove may be disposed so that the groove is not aligned with the axis of the post, such non-alignment potentially having a similar benefit relative to the mixing of fluids during injection or the flushing of the connector and catheter after injection. Further modifications may be made wherein the groove does not have a consistent cross-section axially between distal and proximal ends. That is, as illustrated in the embodiments above, the groove has the same cross-section in all planes orthogonal to the axis of the post. However, it is possible to have a groove that varies in shape or orientation instead, such that the groove “twists” between the ends of the post, or has a tapering cross-section between the ends of the post.
A further embodiment of a needleless connector 550 is illustrated in
Unlike the connector 100, the space 570 is not in communication with a vent. Instead, the space 570 is closed by a surface 574 of the section 564 of the housing 552. When an instrument contacts the gland 556, deformation of the gland 566 will occur, but the fluid (e.g., air) disposed in the space 570 is not able to escape from the space 570. Instead, the air may be compressed into a smaller space, with the wall 568 of the gland 556 collapsing as before, guided by the presence of the reinforcement 572. As such, the embodiment according to
Use of the above-mentioned needleless connector and gland, according to any of the various embodiments described herein, may provide one or more of the following advantages relative to conventional needleless connectors, even those that include mechanisms for limiting retrograde flow. In particular, it is believed that the positioning of the reinforcements inside the space defined by the gland provides a more consistent deformation than in other devices used to provide positive pressure or positive displacement, or neutral displacement for that matter. Further, it is believed that the shape of the end of the gland provides for more consistent application of force by the instrument (Luer syringe, cannula, etc.) to the gland, while maintaining adequate flow.
Still further advantages may be obtained by impregnating the gland, the septum or the housing with an antimicrobial material or composition, or by coating the gland, the septum or the housing with such a material. For example, the antimicrobial material may include chemical disinfectants, for example, alcohols, such as isopropanol and ethanol. Biguanides may also be used, including chlorhexidine and its salts (e.g. chlorhexidine acetate, chlorhexidine gluconate, chlorhexidine hydrochloride and chlorhexidine sulfate). Further examples include, bisphenols, including triclosan, and halogen-releasing agents, including chlorine and iodine compounds. Silver and its salts (e.g. silver acetate, silver iodide, silver nitrate, silver sulfadiazine) may be included, as may copper and its salts. As a further alternative, quaternary ammonium compounds, including benzalkonium chloride, may be used. Still further exemplary alternatives include antimicrobial dyes, including acridines and crystal violet, boric acid, salicylic acid and N-halamines.
