Patent Description:
<CIT> discloses a transdermal injection appliance having a pad impregnated with a disinfectant solution such as alcohol, a body with adhesive for holding the pad against the skin of a patient, and a sleeve with a guide passage through the body for guiding an injection needle.

<CIT> discloses a safety shield apparatus which includes a needle having a distal portion defining a longitudinal axis which is angularly displaced relative to a longitudinal axis defined by a proximal portion of the needle. A shield is mounted with the needle and extensible, via a tubular needle guide movable along the needle, between a retracted position and an extended position. The apparatus may include a needle hub configured to support the proximal portion of the needle. The needle hub can include an appendage which may have at least one opening to facilitate manipulation thereof. A distal end of the shield can be attached to a planar contact surface.

Briefly summarized, embodiments of the present invention are directed to a safety needle assembly of an infusion set for infusing fluids into a subcutaneously implanted access port. The needle assembly is configured to prevent fluid escape therefrom so as to reduce or prevent fluid exposure to a clinician using the needle assembly.

The invention is defined in claims <NUM> and <NUM>: It defines a needle assembly (<NUM>, <NUM>), comprising: A needle hub; and a needle extending from the needle hub; and an interface pad attached to the needle hub before use of the needle assembly, the interface pad including at least one of a haemostatic agent and an antimicrobial agent, the interface pad configured to be interposed between the needle hub and the patient's skin when the needle is percutaneously inserted into the patient, wherein the interface pad includes shape that matches a shape of a bottom surface of the needle hub, the interface pad including a hole through which the needle is configured to extend. The invention also defines a method of manufacturing a needle assembly , the method comprising: providing a needle hub, a needle distally extending from the needle hub; and permanently adhering an interface pad to a bottom surface of the needle hub, the needle configured to extend through the interface pad, the interface pad including at least one of a haemostatic agent and an antimicrobial agent.

These and other features of embodiments of the present invention will become more fully apparent from the following description and appended claims, or may be learned by the practice of embodiments of the invention as set forth hereinafter.

Reference will now be made to figures wherein like structures will be provided with like reference designations. It is understood that the drawings are diagrammatic and schematic representations of exemplary embodiments of the present invention, and are neither limiting nor necessarily drawn to scale.

For clarity it is to be understood that the word "proximal" refers to a direction relatively closer to a clinician using the device to be described herein, while the word "distal" refers to a direction relatively further from the clinician. For example, the end of a needle placed within the body of a patient is considered a distal end of the needle, while the needle end remaining outside the body is a proximal end of the needle. Also, the words "including," "has," and "having," as used herein, including the claims, shall have the same meaning as the word "comprising.

Embodiments of the present invention are generally directed to a safety infusion set and accompanying needle assembly for infusing fluids, such as chemotherapy agents or other medicaments for example, into an access port or other medical device subcutaneously implanted into the body of a patient. The infusion set and/or needle assembly includes one or more components for isolation of the fluid, including vapors thereof, which may otherwise leak from a needle or other portion of the infusion set. This in turn reduces or prevents possible clinician exposure to the fluid/vapors, which in some cases may be hazardous. Potential harm to the clinician is therefore reduced.

Reference is first made to <FIG>, which depicts an infusion set generally designated at <NUM>, including a safety needle assembly ("needle assembly") <NUM> and one or more extension legs <NUM>. The infusion set <NUM> is employed to gain access to a subcutaneously implanted access port or other device disposed below the skin of a patient in order to infuse medicaments or other fluids into the patient, and to withdraw fluids therefrom. A luer connector <NUM> is included on a proximal end of the extension leg <NUM> so as to enable the infusion set <NUM> to be placed into fluid communication with a fluid delivery device or system. A cap <NUM> can be disposed in the luer connector <NUM> to cover the opening thereof.

<FIG> shows that the needle assembly <NUM> includes a needle <NUM> extending from a handle <NUM> and in fluid communication with the tubing of the extension leg <NUM>. A needle safety component <NUM> is also included in the needle assembly <NUM>, including dual extensible wings that are hinged so as to be selectively extended to substantially cover the length of the needle <NUM> and isolate a distal end 30A thereof after use of the needle assembly <NUM> in order to prevent an unintended needle stick of the clinician by the needle tip. Examples of such a hinged safety assembly can be found in <CIT>.

As best seen in <FIG>, the needle assembly <NUM> further includes a fluid isolation component <NUM> for isolating any fluid or vapor that may unintentionally escape from the needle <NUM> during use of the needle assembly. Specifically, the fluid isolation component <NUM> in the present example includes absorbent pads <NUM> disposed on an inner surface 42A of each wing <NUM> of the needle safety component <NUM>. The pads <NUM> are disposed such that when the wings <NUM> of the needle safety component <NUM> are deployed to cover the distal tip 30A of the needle <NUM> (<FIG>), the pads sandwich the body and distal tip of the needle therebetween. Any fluid present on an external surface of the needle or any fluid/vapor leaking from the distal end thereof is captured and absorbed by the pads <NUM>, thus preventing escape of the fluid, which as mentioned above may contain hazardous substances. This in turn protects the clinician from fluid exposure.

<FIG> show the manner in which the wings <NUM> of the needle safety component <NUM> extend to cover the needle <NUM> and its distal tip 30A, and additionally the manner in which the pads <NUM> sandwich and partially encapsulate the needle <NUM>, including its external surfaces and its distal tip 30A, to prevent fluid/vapor escape. In one example, the pads <NUM> can include an absorbent foam and/or rubber material, though many other suitable materials can be employed, including activated charcoal, etc..

<FIG> and <FIG> show the infusion set <NUM> including a needle assembly <NUM> according to another example, wherein the needle assembly includes a handle portion <NUM> with handles <NUM> extending therefrom. A needle <NUM> extends from the handle portion <NUM> and initially through a safety assembly <NUM> that is slidably disposed with respect to the needle <NUM> so as to be axially slidable therewith. The safety assembly <NUM> includes a base <NUM> that houses a needle safety component <NUM> (<FIG>) for shielding a distal tip 130A of the needle <NUM> when use of the needle assembly is complete.

The needle assembly <NUM> further includes a fluid isolation component <NUM> for isolating any fluid or vapor that may unintentionally escape from the needle <NUM> during use of the needle assembly. Specifically, the fluid isolation component <NUM> in the present example includes a conically shaped, extensible shroud <NUM> disposed about the body of the needle <NUM> and extending between the handle portion <NUM> and the axially slidable safety assembly <NUM>. Including plastic such as PET or other substantially impermeable, collapsible, and suitable durable material, the shroud <NUM> forms a hollow cone about the needle <NUM> and is corrugated with corrugations <NUM> in a bellows-like manner to enable it to fold up compactly when the safety assembly <NUM> is undeployed (<FIG>) and to extend to cover and substantially encompass the needle <NUM> when the safety assembly <NUM> is deployed (<FIG>), i.e., the safety assembly is axially slid down the needle <NUM> toward the distal tip 130A such that the needle safety component <NUM> shields the distal tip. <FIG> depict the manner of deployment of the safety assembly <NUM> and the extension of the corrugated shroud <NUM>. In the extended state shown in <FIG> and <FIG>, the shroud <NUM> assists in isolating fluids/vapors present on the needle <NUM> or emitted from the needle distal tip 130A from contact with the clinician.

Note that examples of safety needles that can utilize principles discussed here and in other embodiments herein can be found in the following United States patent and patent applications: Patent No. <CIT>; <CIT>; <CIT>; and <CIT>.

The shroud <NUM> as the fluid isolation component <NUM> can include other configurations. One such configuration is shown in <FIG>, wherein the shroud includes a plurality of interlocked, telescoping segments that are extendible to cover and encompass the needle body when the safety assembly <NUM> is deployed (<FIG>). When the safety assembly <NUM> is undeployed, the telescoping segments <NUM> are stacked together, as shown in <FIG>. Again, these and other configurations for encompassing the needle body illustrate manners by which a fluid isolation component can isolate the needle body and tip in order to prevent fluid exposure to clinician.

<FIG> depict details of the needle safety component <NUM> of the needle assembly <NUM> of <FIG>. Particularly, <FIG> depict bottom views of the needle assembly <NUM>. The needle safety component <NUM> is shown, including a coiled wire torsion spring <NUM> included within the base <NUM> of the safety assembly <NUM>. The spring includes at one end thereof an obstruction component, i.e., a looped portion <NUM> that is biased to lie against the needle <NUM> when the needle extends through a hole 136A defined in the base <NUM> of the safety assembly <NUM>, as shown in <FIG>. As shown in <FIG>, once the distal tip of the needle <NUM> is withdrawn into the base <NUM> in connection with extension of the safety assembly <NUM> (e.g., <FIG>, <FIG>, <FIG>), the spring <NUM> expands such that the looped portion <NUM> slides over the needle hole 136A to prevent re-emergence of the needle distal tip.

In addition, a fluid isolation component <NUM> is included with the spring <NUM> for isolating any fluid or vapor that may unintentionally escape from the needle <NUM> during use of the needle assembly. Specifically, the fluid isolation component <NUM> includes a shield <NUM>, shown in <FIG>, which is attached proximate the looped portion <NUM> of the spring <NUM>. Thus, when the looped portion <NUM> slides over to prevent re-emergence of the distal tip 130A of the needle <NUM> through the hole 136A (<FIG>), the shield fully covers and occludes the hole so as to prevent any fluid/vapor leaking from the distal tip of the needle from exiting through the hole and potentially contaminating the environment or clinician. The shield <NUM> thus serves to occlude the hole 136A and isolate any fluids/vapors from the clinician. Note that the particular size, shape, and configuration of the shield can vary from what is shown and described herein, as can the particular configuration of the needle assembly. In one embodiment, it is appreciated that the shield can include an absorbent material so as to absorb any leaked fluid.

<FIG> depict details of the needle assembly <NUM> according to another example, including a fluid isolation component <NUM> for isolating any fluid or vapor that may unintentionally escape from the needle <NUM> during use of the needle assembly. As shown, the fluid isolation component <NUM> in the present embodiment includes a cylindrical absorption plug <NUM> included with the axially slidable safety assembly <NUM> of the needle assembly <NUM> and including a central cavity so as to be positioned about a portion of the body of the needle <NUM> (<FIG>). The central cavity of the plug <NUM> is sized such that the plug is able to wipe the outer surface of the body of the needle <NUM> as the safety assembly <NUM> is axially slid down the needle toward the distal tip 130A thereof, thus removing fluid from the outer needle surface and capturing it in the plug itself. In addition, once the safety assembly <NUM> has fully shielded the needle distal tip 130A (<FIG>), the plug <NUM> is positioned about the distal opening of the lumen of the needle <NUM> so as to catch and absorb any fluids/vapors emanating therefrom.

It is appreciated that the absorption plug can include a variety of size, type, and material configurations, and can be employed on a variety of needle-based devices where residual fluid/vapor capture is desired. In one embodiment, for instance, the absorption member includes activated charcoal. In other embodiments, other materials and membranes can be employed, including silica gel, clays, activated alumina, zeolites, <NUM> micron or other filtration material, etc. The description included herein is therefore not intended to limit the present disclosure in any way.

<FIG> shows details of a fluid isolation component <NUM> according to another example, including an absorption disk <NUM> included with the safety assembly <NUM>. The absorption disk <NUM> is disposed above the needle safety component <NUM> in the safety assembly base <NUM> and is slit to enable the needle <NUM> to pass therethrough. Extension of the safety assembly <NUM> down the length of the needle <NUM> enables the absorption disk <NUM> to wipe the outer needle surface so as to remove any fluid present thereon. In addition, once the safety assembly <NUM> is fully extended to shield the needle <NUM> (<FIG>), the absorption disk <NUM> is positioned so as to absorb any fluid/vapor leaking from the distal lumen opening at the needle distal tip 130A. As with the previous example, the absorption disk <NUM> in one example includes activated charcoal or other suitable, absorbent material as outlined above in connection with the absorption plug <NUM> shown in <FIG>. The position, shape, thickness or other configuration of the absorption disk can vary from what is shown and described herein.

<FIG> depict various details of a needle assembly <NUM> that can include a fluid isolation component, according to one example. As shown, the needle assembly <NUM> includes a handle portion <NUM> from which extends a needle <NUM>. The needle <NUM> initially extends through a safety assembly <NUM> that is slidably disposed with respect to the needle so as to be axially slidable therewith. The safety assembly <NUM> includes a base <NUM> that houses a needle safety component <NUM> (<FIG>) for shielding a distal tip 230A of the needle <NUM> when use of the needle assembly is complete.

In greater detail, <FIG> show that the needle safety component <NUM> includes two spring-based shutters <NUM> that each define a hole <NUM> through which the needle <NUM> passes when the needle extends through the safety assembly <NUM> and out a hole 236A defined in the base <NUM>, such as in the configuration shown in <FIG>. The shutters <NUM> each further include a spring arm <NUM>. As seen in <FIG>, when the safety assembly <NUM> is undeployed (<FIG>), the holes <NUM> of the shutters <NUM> are aligned so that the needle <NUM> passes therethrough. This constrains the shutters <NUM> and spring arms <NUM> into the configuration shown in <FIG>.

When the safety assembly <NUM> is actuated, however, it is slid down the length of the needle <NUM> so as to cause the needle distal tip 230A to recede from the hole 236A and the shutter holes <NUM> so as to be shielded within the safety assembly base <NUM>. As shown in <FIG>, this causes the shutters <NUM> to no longer be constrained by the needle <NUM> and enables the shutter spring arms <NUM> to slide the shutters laterally within the base <NUM> so as to cover and occlude the hole 236A defined in the base, thus preventing reemergence of the needle distal tip 230A. Note that further information regarding this and other related needle safety assemblies can be found in <CIT>, titled "Method of Retaining a Tip Protector on a Needle with a Curved Tip.

In accordance with one example the needle assembly <NUM> includes a fluid isolation component <NUM> for isolating any fluid or vapor that may unintentionally escape from the needle <NUM> during use of the needle assembly. Specifically, the fluid isolation component <NUM> in the present embodiment includes an absorption pad <NUM> disposed on a backside of one or both of the shutters <NUM> of the safety assembly <NUM>. As shown in <FIG>, the pad <NUM> is disposed on the shutter <NUM> so that the distal tip 230A of the needle <NUM> rests against it after the distal tip has been withdrawn and shielded by the base <NUM> of the safety assembly <NUM>. Should any fluid leak from the distal opening of the lumen of the needle <NUM>, it can be readily captured by the pad <NUM>, thus preventing its escape outside of the safety assembly <NUM>. The pad can include one or more of suitable materials including those listed above in connection with the example of <FIG>, silicone, rubber, etc. As shown, the pad can also be recessed within the shutter <NUM> so as to provide a basin for capture of the fluid, in one example. Note that the pad and shutters can vary in size, number, shape, design, etc..

<FIG> shows the needle assembly <NUM> including a fluid isolation component <NUM> according to one example, wherein the fluid isolation component includes an O-ring <NUM> that is disposed within the safety assembly <NUM> about a portion of the needle <NUM>. So positioned, the O-ring <NUM> wipes the length of the needle <NUM> when the safety assembly <NUM> is axially slid down the needle in order to shield the needle distal tip 230A. The O-ring <NUM> is sized such that its wiping action cleans the outer needle surface of any fluids that might otherwise be exposed to the clinician and prevents their escape from the safety assembly base <NUM>. In one embodiment, the O-ring can be configured to be absorbent so as to soak up any fluid it comes into contact with during wiping of the needle. Note that the O-ring can be placed in other locations with respect to the needle safety assembly and that the needle housing and safety assembly can vary in configuration from what is shown.

<FIG> depict various details of a needle assembly <NUM> including a fluid isolation component, according to one example. The needle assembly <NUM> includes a handle portion <NUM> from which extends a needle <NUM>. The needle <NUM> initially extends through a hole <NUM> defined in a safety assembly <NUM> that is pivotally movable with respect to the handle portion <NUM> and the needle <NUM> via a hinge point <NUM>. The safety assembly <NUM> houses a needle safety component <NUM> including a laterally slidable shutter <NUM>, disposed in a shutter cavity <NUM>, for shielding a distal tip 330A of the needle <NUM> when use of the needle assembly is complete. A foam pad <NUM> is disposed on the bottom of the safety assembly <NUM>.

As shown in <FIG>, the needle <NUM> is biased while residing in the hole <NUM> of the safety assembly <NUM> such that when the distal tip 330A is withdrawn from the hole, the needle <NUM> urges the shutter <NUM> to laterally slide within the shutter cavity <NUM>, thus covering the hole and preventing re-emergence of the needle distal tip. In another example, the shutter itself can be biased to urge the needle distal tip laterally.

The needle assembly <NUM> further includes a fluid isolation component, here configured as an extensible shroud <NUM> that extends about the needle <NUM> between the handle portion <NUM> and the safety assembly <NUM> to isolate the body of the needle and any vapors present therewith. Thus, the shroud <NUM> provides isolation of fluids present on the needle <NUM>. In addition, the shutter <NUM> provides some fluid isolation as well.

<FIG> disclose a luer connector <NUM> including a fluid isolation component, according to one example. As shown, the connector <NUM> is a female-type luer connector, though the principles described here can be extended to other connective or fluid-carrying components of an infusion set or other suitable fluid delivery medical device. Connected to the extension leg tubing <NUM>, the connector <NUM> includes a body that defines a cavity <NUM> suitable for receiving a male-type connector <NUM> (<FIG>) therein. The connector <NUM> can include threads to enable the male connector <NUM> to threadably connect therewith. The cavity <NUM> defines a portion of a fluid pathway through the connector body.

A fluid isolation component <NUM> is included in the connector <NUM>. In particular, the fluid isolation component <NUM> in the present embodiment includes a slit valve <NUM> that is disposed in the fluid pathway defined by the connector <NUM>. Other suitable types of valves may also be employed.

As seen in <FIG>, when the male connector <NUM> is received but not fully seated within the cavity <NUM> of the female connector <NUM>, the valve <NUM> remains closed, thus isolating any fluid contained in the extension leg tubing <NUM> attached thereto. When the male connector <NUM> is fully inserted into the female connector <NUM>, the distal end of the male connector engages and opens the valve <NUM>, thus allowing fluid flow therethrough. This configuration of the connector <NUM> thus serves as one example a connector-based fluid isolation component; other configurations of this principle are contemplated.

<FIG> and <FIG> depict another example of a fluid isolation component for preventing unintended contact with fluid or vapors resulting from use of an infusion set. In particular, an infusion set <NUM> is shown, including a needle assembly <NUM>, extension leg tubing <NUM>, and luer connector <NUM>. Also shown is a fluid isolation component <NUM>, which in the present example includes a bag <NUM> of plastic or other substantially fluid-impermeable material. The bag includes a sealable open end <NUM> and a closed end <NUM>. The bag <NUM> is attached to the tubing <NUM> of the infusion set <NUM> or other suitable component thereof via and adhesive strip <NUM> or other suitable connective apparatus.

The bag <NUM> is initially inside-out before use of the infusion set <NUM>. Once use of the infusion set <NUM> has ended, the user reaches a hand through the open end <NUM> of the bag <NUM> and pulls the infusion set into the bag, turning the bag right side-out in the process. Once the infusion set <NUM> is fully within the bag <NUM>, the open end <NUM> of the bag <NUM> is sealed, as seen in <FIG>, thus isolating the user from any fluids or vapors included on the needle assembly <NUM> or any other portion of the infusion set <NUM>. Note that the bag can be configured in one or more sizes and shapes, can include one-time, resealable, or other suitable type of sealing mechanism, and can be included with the infusion set in a variety of ways, both attached and detached thereto. The bag in the present embodiment is transparent, though in other embodiments it need not be.

<FIG> depicts details of another possible fluid isolation component for use with the needle assembly <NUM> (shown in <FIG>), or another suitable needle assembly. In particular, a fluid isolation component <NUM> is disclosed, including an amount of suitable viscous oil <NUM>, such as silicone oil, interposed as a film between the shutters <NUM>. When the needle <NUM> is retracted from the hole 236A in the needle assembly base <NUM>, which retraction causes the shutters <NUM> to slide over and cover the hole, the oil <NUM> produces a fluid impermeable barrier layer between the shutters, thus preventing any fluid/vapor escaping the needle from escaping past the shutters. In other examples, other barriers can be employed between the shutters, including a gasket, O-ring, other compliant/elastomeric member, etc..

<FIG> depict various details regarding a fluid isolation component according to yet another example, for use with a safety needle assembly. As will be described, the fluid isolation component in the present example includes a self-sealing pad that prevents unintended leakage of fluids (e.g., liquids, gases) from the needle after use of the needle assembly. The self-sealing pad thus prevents undesired exposure to clinicians of potentially hazardous substances.

<FIG> and <FIG> show the needle assembly <NUM> in similar configuration to that described further above in connection with <FIG>. As before, the needle assembly <NUM> includes a first needle assembly portion, i.e., the handle portion <NUM>, with handles <NUM> extending therefrom. The hollow needle <NUM> extends from the handle portion <NUM> and initially through the safety assembly <NUM> that is slidably disposed with respect to the needle <NUM> so as to be axially slidable therewith. The safety assembly <NUM> includes the base, also referred to herein as a second needle assembly portion or the base portion <NUM>, which houses the needle safety component <NUM> (<FIG>) for shielding the distal tip 130A of the needle <NUM> when use of the needle assembly is complete.

As already described further above, the needle assembly <NUM> further includes a first fluid isolation component <NUM> for isolating any fluid or vapor that may unintentionally escape from the needle <NUM> during use of the needle assembly. Specifically, the first fluid isolation component <NUM> includes the conically shaped, extensible shroud <NUM> disposed about the body of the needle <NUM> and extending between the handle portion <NUM> and the axially slidable safety assembly <NUM> of the base portion <NUM>. The shroud <NUM> forms a hollow cone about the needle <NUM> and is corrugated with corrugations <NUM> in a bellows-like manner to enable it to fold up compactly when the safety assembly <NUM> is undeployed (<FIG>) and to extend to cover and substantially encompass the needle <NUM> when the safety assembly <NUM> is deployed (<FIG>). As already discussed. in the extended state shown in <FIG> and <FIG>, the shroud <NUM> assists in isolating fluids/vapors present on the needle <NUM> or emitted from the needle distal tip 130A from contact with the clinician.

<FIG> further show a self-sealing pad <NUM> disposed on a bottom external surface of the base portion <NUM>. The pad <NUM> includes a self-sealing material that enables the needle <NUM> to extend therethrough, as seen in <FIG> (also referred to as the first needle position), but seals when the needle is retracted back through the pad via separation of the base portion <NUM> from the handle portion <NUM>, as seen in <FIG> (also referred to as the second needle position). In particular, and as shown in <FIG>, the full extension of the base portion <NUM> from the handle portion <NUM> causes the distal tip 130A of the needle <NUM> to be drawn through the pad <NUM> such that the distal tip is shielded within the base portion, in particular, shielded by the needle safety component <NUM>. Because of its self-sealing characteristics, the pad <NUM> substantially seals the hole through which the needle <NUM> was disposed during needle assembly use, thus preventing any fluid leakage from the distal opening of the needle <NUM> to escape the base portion <NUM>, as desired. Note that, though shown and described herein in connection with the needle assembly <NUM>, the self-sealing pad <NUM> can be included with needle assemblies and infusion sets of a variety of configurations in addition to those discussed herein.

<FIG> depict various features of the self-sealing pad <NUM> according to the present embodiment. As shown, the pad <NUM> includes a body <NUM> shaped to conform to the shape of the base <NUM>, though in other embodiments the pad could include other shaped configurations. The body <NUM> defines an upper surface 502A that is configured to mate with the base portion <NUM> and a bottom surface 502B that serves as a skin-contacting surface for the needle assembly <NUM>.

A groove <NUM> is defined about the perimeter and configured in the present embodiment to receive therein a corresponding protruded surface <NUM> defined on a bottom surface of the base portion <NUM>. The receipt of the protruded surface <NUM> by the groove <NUM> assists in maintaining engagement of the pad <NUM> with the base portion <NUM>, in one embodiment. The pad <NUM> can be affixed to the base portion <NUM> via a suitable adhesive or by other suitable methods, including mechanical fixation.

In one example, the pad <NUM> includes silicone, though other self-sealing materials, plastics, and elastomers can be employed. In one embodiment, a liquid silicone rubber ("LSR") that is injection molded then cured is employed to form the pad <NUM>. So configured, the skin-contacting bottom surface 502B of the pad <NUM> provides a compliant surface to rest against the skin of the patient during use of the needle assembly <NUM>.

The pad body <NUM> further defines a centrally disposed raised portion <NUM>, best seen in <FIG>, which is shaped so as to compressively fit within an opening 136A that is defined in the base portion <NUM>. As shown in <FIG>, the raised portion <NUM> of the pad <NUM> is disposed within the opening 136A and is partially maintained in place via a compressive fit with the opening. So configured, the raised portion <NUM> acts as a septum to provide a robust fluid barrier when the needle <NUM> is withdrawn therethrough and shielded by the safety assembly <NUM>, which occurs when the base portion <NUM> is selectively extended from the handle portion <NUM>, as shown in <FIG>. Indeed, compression of the raised portion <NUM> by the opening 136A assists in the self-sealing characteristics of the pad <NUM> when the needle <NUM> is retracted, in one example. Thus, the self-sealing pad <NUM> serves as a second fluid isolation component, together with the shroud <NUM>, for preventing fluid/vapor escape from the needle assembly. The shape and size of both the raised portion and the opening can vary from what is shown and described herein. In the present example, the distal tip 130A of the needle <NUM> fully withdraws from the raised portion <NUM>, though in other examples the distal tip can remain in the raised portion <NUM> after shielding thereof by the safety assembly. An example of the latter configuration would include the distal tip of the needle retracting fully from the lower surface 502B of the pad body while still residing within raised portion <NUM> of the pad.

The self-sealing pad can be configured in other ways. For instance, <FIG> shows the bottom surface 502B as including a plurality of texture features <NUM> for increasing patient comfort while the needle assembly <NUM> is disposed on the skin of the patient. Also, in one embodiment, it is appreciated that the self-sealing pad can be treated so as to offer antimicrobial/antibacterial properties. Further, in one example, the bottom surface of the self-sealing pad can include an adhesive material to enable the pad to act as a securement device in maintaining the infusion set in place at a desired position on the patient's skin during use of the needle assembly. It is further appreciated that the needle assembly and accompanying infusion set can include one of many possible shapes, sizes, and configurations in addition to those shown and discussed herein.

<FIG> depict various features of an interface pad or other structure for inclusion on a medical device, such as a needle assembly or catheter assembly, so as to provide an interface between the medical device and the skin surface of the patient after the device has been percutaneously inserted into the patient via an insertion site. Particularly, the interface pad is positioned on the medical device so as to rest against the insertion site on the patient's skin once the device has been inserted into the patient.

Further, the interface pad includes one or more components that provide desirable effects at the insertion site. In accordance with one example, for instance, an antimicrobial agent and/or haemostatic agent are impregnated into the interface pad so as to provide antimicrobial and/or haemostatic properties to the insertion site via contact of the agents from the pad with the insertion site. In this way, infection, undesired bleeding, etc. can be controlled via use of the interface pad. In addition to the above-mentioned agents, other substances can be included in the interface pad to impart other desirable characteristics, such as antithrombogenic agents, for instance.

Reference is first made to <FIG>, which shows a catheter assembly ("catheter"), generally designated at <NUM>, according to one example. As shown, the catheter includes a hub <NUM> to which is connected at a distal end thereof an elongate, hollow catheter tube <NUM> defining a lumen <NUM>. The catheter <NUM> includes a needle <NUM> inserted through the hub <NUM> so as to extend into the lumen <NUM> of the catheter tube <NUM>. The needle <NUM> is used to assist with percutaneous insertion of the catheter tube <NUM> into the body of the patient via an insertion site <NUM> (<FIG>). Once the catheter <NUM> is percutaneously inserted within the patient, the hub <NUM> rests above a skin surface <NUM> of the patient, as seen in <FIG>. Note that, though shown here as defining a single lumen <NUM>, the catheter tube <NUM> can define more than one lumen, such as two, three, or more lumens, in one embodiment. Also note that, though describing a catheter assembly herein, the present disclosure contemplates that other types of catheters including PICCs, PIVs, midline and intermediate dwell catheters, Foley and balloon catheters, epidural catheters, feeding catheters, drainage catheters, infusion sets, needle assemblies, and other medical devices can benefit from the teachings herein. The discussion to follow, therefore, is not intended to be limiting of the present disclosure.

<FIG> further shows an interface pad ("pad") <NUM>, configured according to one example, attached to catheter <NUM>. As shown, the pad <NUM> is interposed between the distal end 614B of the hub <NUM> and the skin surface <NUM> so as to rest adjacent to and substantially cover the insertion site <NUM> (<FIG>) when the catheter <NUM> is percutaneously inserted into the patient.

<FIG> depict further details of the pad <NUM>, according to one example. As shown in <FIG>, the pad <NUM> includes a compliant body <NUM> that can be permanently or temporarily attached to the distal end 614B of the hub <NUM>, though other attachment locations to the medical device are possible. As will be seen, the pad body <NUM> can be configured in any one of a variety of shapes, sizes, etc. In the present example, the pad body <NUM> defines a disk-shaped configuration and is adhered by an adhering surface <NUM> to the hub distal end 614B via a biocompatible adhesive, though other modes of attachment, including chemical, mechanical, frictional, etc., can be employed. Example adhesives in one example include cyanoacrylate, UV- or heat-cured adhesives, epoxies, solvent bonding adhesives, acrylic-based, silicone-based, rubber-based, urethane-based, and hydrocolloid adhesives. In other examples, the interface pad is not compliant or compressible, but substantially rigid. For instance, an incompressible polymeric material that includes the ability to leach one or more agents (discussed below) for treating the insertion site <NUM> could be employed for the pad body <NUM>. These and other variations of the pad are therefore contemplated.

Though a variety of suitable, biocompatible materials can be employed, in the present example the pad body <NUM> includes a compressible polyurethane foam that is capable of absorbing and holding agents (discussed below) that may be impregnated into the foam. Manufacture of the pad body <NUM> from a compressible/compliant material enables the pad to conform to the skin surface <NUM> about the insertion site <NUM> when the catheter tube <NUM> is percutaneously inserted into the patient's body. As such, one or more portions of an outer surface of the pad body <NUM> serve as a deformable contact surface <NUM> so as to provide a cushioning interface between the catheter hub <NUM> and the patient skin <NUM>, as seen in <FIG> and <FIG>. The cushioning effect of the pad body <NUM> serves to increase patient comfort when the catheter is disposed in the patient.

Specifically, in one example, the pad body <NUM> includes an aromatic polyether polyurethane foam, including a TDI or MDI hard segment and a PTMEG (polytetramethylene ether glycol) soft segment. Other suitable polymer-based foam materials as well as non-foam materials can also be employed for the pad body <NUM>. In one example, desired characteristics for a foam material used for the pad body <NUM> include hydrophilicity (absorptive), a suitably large surface area to volume ratio for the foam, and a suitable diffusion coefficient. These desired characteristics are useful when one or more agents for treating the insertion site <NUM> are included with the pad body <NUM>, as will be described below. In addition, other materials can be employed, including polyethylene, woven and non-woven fabrics including felt and cotton, gels, and hydrogels. In one example, the pad body includes a compressed foam that expands in size upon activation with blood or other body fluid/liquid. In such an example a dry antimicrobial or other agent can be included with the pad body.

As mentioned above, the pad <NUM> is configured in one example to include one or more agents for treating the insertion site <NUM> of the catheter <NUM> or other medical device. In one example, a liquid solution (or other suitable medium) including an antimicrobial agent, a haemostatic agent, an antithrombogenic agent, or other substance to protect, heal, or otherwise assist care of the insertion site <NUM> is included in the pad body <NUM>. In the present example, the pad <NUM> includes a liquid antimicrobial agent that is infused during manufacture into the polyurethane foam material from which the pad body <NUM> is formed. Once the catheter <NUM> has been placed percutaneously into the patient and the pad <NUM> is positioned adjacent the patient skin <NUM> as shown in <FIG>, the antimicrobial agent previously infused into the foam pad body <NUM> contacts the insertion site <NUM> via the contact surface <NUM> of the pad body <NUM> and provides antimicrobial effect, thus desirably protecting the insertion site from infection.

In the present example, a liquid haemostatic agent is also infused during manufacture into the polyurethane foam material from which the pad body <NUM> is formed. When the pad <NUM> is positioned adjacent to the insertion site <NUM> as just described and as shown in <FIG>, the haemostatic agent previously infused into the foam pad body <NUM> contacts the insertion site via the contact surface <NUM> of the pad body <NUM> and provides haemostatic effect, thus desirably preventing excessive bleeding from the insertion site. Note that the pad body <NUM> in one example is absorptive so as to take up effusion of blood and other fluids from the insertion site <NUM>, in one embodiment.

In one example, the antimicrobial agent can include silver, copper (and other biocompatible antimicrobial metals, silver sulfadiazine, chlorhexidine, chlorhexidine gluconate ("CHG"), chlorhexidine acetate ("CHA"), other suitable chlorhexidine-based antimicrobial agents, isopropyl alcohol ("IPA"), etc. In one example, the haemostatic agent includes microdispersed oxidized cellulose, other suitable hydrocolloids, etc. In one example embodiment, a solution included in the pad <NUM> includes an antimicrobial agent of about <NUM>% by weight CHG and a haemostatic agent of about <NUM>% by weight microdispersed oxidized cellulose, though these percentages can vary in other formulations. For example, in one example, the amount of CHG by weight in the solution can vary between about <NUM>% to about <NUM>%, though other ranges are possible, depending on various factors, including the type of pad material employed, processing parameters during pad manufacture, etc. In another example, it is appreciated that the antimicrobial agent, haemostatic agent, or other agent included with the interface pad can be in a dry state, such as a solid or powder, for instance.

In yet another example, the foam itself of the interface pad body can be configured to impart haemostatic properties and therefore act as the haemostatic agent. Indeed, in one example, negatively charged sulfonate groups can be incorporated into the soft segment (e.g., polytetramethylene ether glycol) of a polyurethane foam so as to impart haemostatic properties thereto. In such a case, no other haemostatic agent need be added, though an additional agent could be, if desired.

Further details regarding antimicrobial and haemostatic agents that may be used according to one embodiment are found in <CIT>, and titled "Dressing Device for Use with a Cannula or a Catheter,". In yet another example, the antimicrobial agent (such as CHG) is incorporated into the material from which the interface pad body is composed, such as a solvent acrylic adhesive. Details regarding such a configuration can be found in <CIT>, and titled "Chlorhexidine Gluconate Containing Solvent Adhesive,". In yet another example, an antimicrobial silicone adhesive, such as that produced by Covalon Technologies Ltd. , Mississauga, Ontario, can be used to form the interface pad body and antimicrobial agent. In yet another example, a hydrogel or other hydrocolloid in which the antimicrobial and/or haemostatic agent is incorporated can be used to form the interface pad body.

It is appreciated that one or more of a variety of agents can be included with the pad <NUM> to render to it desirable qualities or characteristics. For instance, the pad body can include an antithrombotic agent. Note also that in one embodiment, the antimicrobial/haemostatic agent can be incident on the insertion site <NUM> via liquid dispersion.

It is further appreciated that, in one example, the afore-mentioned desirable qualities of the pad body material - including hydrophilicity/absorptiveness and sufficiently large surface area to volume ratio - assist in enabling the microdispersed oxidized cellulose haemostatic agent to be present in the pad body and to contact and interact with the insertion site, as desired. Additionally, in one example the afore-mentioned desirable quality of suitable diffusion coefficient for the pad body material assists in enabling the antimicrobial agent to contact and interact with the insertion site so as to provide desired antimicrobial properties.

In addition to agent-based protection, the pad <NUM> also physically protects the insertion site <NUM> by providing a physical barrier and cushion for the insertion site, which provide patient comfort when the catheter <NUM> or other medical device is resting against the skin, as seen in <FIG>. As such, it is appreciated that the pad can be manufactured using one or more of a variety of materials and in a variety of shapes, sizes, and configurations. In one example, as mentioned, the pad body includes a gel or hydrogel material.

In light of the above, <FIG> depict various examples of possible shapes for the body <NUM> of the pad <NUM>, according to examples. <FIG> show the pad body <NUM> defining a central hole <NUM> for passage therethrough of the needle <NUM> (<FIG>), similar to the pad configuration of <FIG>. In one example, the thickness of the pad body <NUM> of <FIG> is about <NUM> (<NUM> inch), though other thicknesses are possible. Generally, the thickness of the pad body should be such that sufficient absorption of the antimicrobial and/or haemostatic agents is possible, while not becoming too thick so as to decrease the useful length of the catheter tube.

<FIG> show a rectangular pad body <NUM>, wherein a hole therethrough for passage of the catheter <NUM> may be made by piercing the pad body with the needle <NUM> during the catheter insertion procedure or during manufacture.

<FIG> show a disk-like pad body <NUM> with a slit <NUM> defined from an edge of the disk to the center thereof to enable its attachment to or removal from the catheter <NUM>. As such, it is appreciated that the pad <NUM> can be permanently or removably attached to the catheter hub <NUM>, such as is seen in <FIG> or in another suitable location, as appreciated by one skilled in the art. These and other suitable pad body shapes and configurations are therefore contemplated.

<FIG> depicts details of another possible shape configuration for the pad <NUM>, wherein the pad body <NUM> defines an angular shape, from the perspective shown in <FIG>, such that the contact surface <NUM> thereof is substantially parallel to the skin surface <NUM> when the catheter tube <NUM> is percutaneously inserted into the patient, as shown. Such a configuration distributes the contact load of the pad <NUM> with the patient skin <NUM> across the relatively parallel and flat contact surface <NUM>, thus diminishing contact force at any given point on the contact surface, which increases patient comfort, and increases the relative surface area of the contact surface about the insertion site to enhance the effectiveness of the antimicrobial and/or haemostatic agents.

<FIG> depicts yet another possible pad configuration to maximize skin contact, wherein the pad body <NUM> approximately defines a parallelogram shape, from the perspective shown in <FIG>, which also desirably produces a relatively parallel pad contact surface with respect to the skin surface <NUM>. <FIG> further shows that, in one example, the distal end 614B of the hub <NUM> can be angled to be substantially parallel with the skin surface <NUM> after percutaneous catheter insertion is completed.

<FIG> depict details of another example of the interface pad <NUM>, wherein the pad is produced from a foam strip <NUM> that includes a pattern of spaced-apart teeth <NUM>, as seen in <FIG>. During pad manufacture, the foam strip <NUM> is rolled about the proximal end 612A of the catheter tube <NUM> and secured in its rolled configuration (via adhesive or the like) to define the interface pad <NUM> shown in <FIG>. The toothed pattern of the foam strip <NUM> imparts an angled configuration for the pad body, which assists in providing a contact surface for the pad that is relatively more parallel to the skin surface <NUM> of the patient, as has been discussed. Note that the teeth <NUM> shown here is just one of a variety of different patterns that can be included in the foam strip <NUM> from which the pad <NUM> can be manufactured.

<FIG> depict details of an interface pad <NUM> according to one example. As shown, the pad <NUM> includes a body <NUM> that defines a cavity <NUM> so as to form a cap-shaped configuration. So configured, the cavity <NUM> of the pad body <NUM> receives a portion of the catheter hub <NUM> therein such that the distal end of the hub is covered, or capped, by the pad. The pad <NUM> can be temporarily or permanently secured to the hub <NUM> along an adhering surface <NUM> via adhesive or other suitable fixation mode. The pad <NUM> defines an outer contact surface <NUM> for deformable contact with the skin surface <NUM>. As before, the pad <NUM> can include an antimicrobial, haemostatic, or other suitable agent for protecting/healing the insertion site <NUM> of the catheter <NUM> and for destroying microbes that may otherwise be present on portions of the catheter tube <NUM> in contact with the interface pad. Also, in one example, the pad <NUM> can be scored or include a slit so as to make it readily removable from the catheter hub or other medical device to which it is at least temporarily attached.

<FIG> depict details of the interface pad <NUM> according to one example, wherein the pad is produced from a foam strip, such as the foam strip <NUM> shown in <FIG>. As shown in <FIG>, during pad manufacture, the foam strip <NUM> is rolled about the catheter tube <NUM>. The foam strip <NUM> can include a liner <NUM> that is peeled away during rolling such that an adhesive under the liner adheres the pad to the catheter tube <NUM> and/or hub <NUM>. Once the foam strip <NUM> has fully encircled the catheter tube <NUM>/hub <NUM>, it can be cut to define the pad <NUM> shown in <FIG>. These and other pad manufacturing methods are therefore contemplated. The foam strip <NUM> can include one of a variety of lengths, thicknesses, compositions, and other configurations.

<FIG> shows yet another example for providing an antimicrobial/haemostatic interface for the catheter <NUM>, wherein a proximal portion of the catheter tube <NUM> adjacent the proximal end 612A thereof is coated to provide a coated portion <NUM> that includes an antimicrobial, haemostatic, and/or other suitable agent for protecting and/or healing the insertion site of the catheter <NUM> through the skin <NUM> of the patient. The amount of the proximal portion of the catheter tube that is coated to form the coated portion <NUM> can vary according to need, catheter size, amount of the catheter to remain outside the patient body, etc., but in one example, the coated portion <NUM> extends distally from about one to about five millimeters from the distal end 614B of the hub <NUM>.

<FIG> depict various details of an interface pad for use with yet another type of percutaneous device, according to embodiments of the present invention. In particular, <FIG> show a safety needle infusion set ("infusion set") <NUM>, typically used to provide percutaneous access to a subcutaneously implanted access port. As shown, the infusion set <NUM> includes a needle assembly <NUM> from which extends tubing <NUM>. The tubing <NUM> is operably connected with a needle hub <NUM> of the needle assembly <NUM> so as to be in fluid communication with a needle <NUM> that extends from the needle hub. The needle hub <NUM> includes an extensible base <NUM> that in turn defines a bottom surface 815A. The base is included as part of a needle safety component to prevent needle sticks to the user by the distal tip of the needle, in one embodiment. A connector <NUM> is included on the opposite end of the tubing <NUM>. As mentioned, the needle <NUM> is configured to percutaneously pierce the patient's skin via an insertion site so as to access a subcutaneously implanted access port.

In accordance with the invention, the needle assembly <NUM> includes an interface pad <NUM> included on the bottom surface 815A of the needle hub base <NUM>. As seen in <FIG>, the interface pad includes a body <NUM> and a hole <NUM> through which the needle <NUM> extends. The composition of the pad body <NUM> and the antimicrobial/haemostatic agents it contains is similar to what has been described in the examples above.

The body <NUM> of the interface pad <NUM> in the present embodiment defines a perimeter <NUM> that is shaped to correspond to the perimeter shape of the needle hub base <NUM>. The interface pad body <NUM> further includes an adhering surface <NUM> where the pad body attaches to the bottom surface 815A of the needle hub base <NUM>, and a contact surface <NUM>. In the present embodiment, the adhering surface <NUM> of the pad body <NUM> is permanently attached to the bottom surface 815A of the needle hub base <NUM> via a suitable adhesive or other mode as discussed herein. In another embodiment, the pad body <NUM> is removably attached. The contact surface <NUM> rests against the skin when the infusion set needle <NUM> is percutaneously disposed within the patient. As has been described, this enables the antimicrobial/haemostatic agents included with the interface pad <NUM> to be in contact with and protect the needle insertion site.

<FIG> shows an infusion set <NUM> and interface pad <NUM> according to another embodiment. As with the previous embodiment, a safety needle infusion set ("infusion set") <NUM> is shown and includes a needle assembly <NUM> from which extends tubing <NUM>. The tubing <NUM> is operably connected with a needle hub <NUM> of the needle assembly <NUM> so as to be in fluid communication with a needle <NUM> that extends from the needle hub. The needle hub <NUM> includes an extensible base <NUM> that in turn defines a bottom surface 915A. The needle hub <NUM> further includes a pair of wings <NUM> for grasping the needle assembly <NUM>. The base <NUM> includes a pair of extensions <NUM> to assist with using the infusion set <NUM>. Note that the particular shape and configuration of the needle assembly can vary from what is shown and described herein. One or more connectors <NUM> are included on the opposite end of the tubing <NUM>. As mentioned, the needle <NUM> is configured to percutaneously pierce the patient's skin via an insertion site so as to access a subcutaneously implanted access port.

In accordance with the invention, the needle assembly <NUM> includes an interface pad <NUM> included on the bottom surface 915A of the needle hub base <NUM>. As seen in <FIG>, the interface pad includes a body <NUM> and a hole <NUM> through which the needle <NUM> extends. The composition of the pad body <NUM> and the antimicrobial/haemostatic agents it contains is similar to what has been described in the examples above.

The body <NUM> of the interface pad <NUM> in the present invention defines a perimeter <NUM> that is shaped to correspond to the perimeter shape of the needle hub base <NUM>, including the shape of the extensions <NUM> of the needle hub base. The interface pad body <NUM> further includes an adhering surface <NUM> where the pad body attaches to the bottom surface 915A of the needle hub base <NUM>, and a contact surface <NUM>. In the present invention, the adhering surface <NUM> of the pad body <NUM> is permanently attached to the bottom surface 915A of the needle hub base <NUM> via a suitable adhesive or other mode as discussed herein. In another example, the pad body <NUM> is removably attached.

As seen in <FIG>, the needle assembly <NUM> of the infusion set <NUM> can be employed to access a subcutaneously implanted access port <NUM>. As shown, the access port <NUM> includes a body <NUM> and a septum <NUM> that cooperate to define a reservoir <NUM>.

As has been described, the contact surface <NUM> of the pad <NUM> of the infusion set needle assembly <NUM> rests against the skin <NUM> when the needle <NUM> of the needle assembly <NUM> is percutaneously disposed within the patient, such as in accessing the access port <NUM> shown in <FIG>. This enables the antimicrobial/haemostatic agents included with the interface pad <NUM> to be in contact with and treat/protect the needle insertion site <NUM>.

Claim 1:
A needle assembly (<NUM>, <NUM>), comprising:
a needle hub (<NUM>, <NUM>); and
a needle (<NUM>, <NUM>) extending from the needle hub (<NUM>, <NUM>); and
an interface pad (<NUM>, <NUM>) attached to the needle hub (<NUM>, <NUM>) before use of the needle assembly (<NUM>, <NUM>), the interface pad (<NUM>, <NUM>) including at least one of a haemostatic agent and an antimicrobial agent, the interface pad (<NUM>, <NUM>) configured to be interposed between the needle hub (<NUM>, <NUM>) and the patient's skin when the needle (<NUM>, <NUM>) is percutaneously inserted into the patient,
characterized in that
the interface pad (<NUM>, <NUM>) includes shape that matches a shape of a bottom surface (815A, 915A) of the needle hub (<NUM>, <NUM>), the interface pad (<NUM>, <NUM>) including a hole through which the needle (<NUM>, <NUM>) is configured to extend.