Abstract:
The present invention related to a catheter device having a side port in which is contained an actuator, the actuator being configured to compress a tubing of the catheter device inwardly when a separated device is inserted into the side port, thereby opening a flowpath from the side port to the inner lumen of the catheter device. In some instances, the side port actuator further comprises an antimicrobial agent or is formed from an antimicrobial material whereby the actuator prevents antimicrobial growth or colonization within fluid that remains in the side port following use thereof.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    The present invention relates generally to inserts for medical devices that are configured to elute an antimicrobial agent. In particular, an actuator for a side port of a ported catheter can be configured to elute an antimicrobial agent to disinfect the side port including any fluid contained within the side port. 
         [0002]    Catheters are commonly used for a variety of infusion therapies. For example, catheters are used for infusing fluids, such as normal saline solution, various medicaments, and total parenteral nutrition into a patient, withdrawing blood from a patient, as well as monitoring various parameters of the patient&#39;s vascular system. 
         [0003]    Catheter-related bloodstream infections are caused by the colonization of microorganisms in patients with intravascular catheters and I.V. access devices. These infections are an important cause of illness and excess medical costs. More importantly, these infections often result in patient deaths. 
         [0004]    Many techniques have been employed to reduce the risk of infection from a catheter or other intravenous device. For example, catheters have been designed that employ an antimicrobial lubricant or an antimicrobial coating on an inner or outer surface of the catheter. Similarly, antimicrobial lubricants or coatings have been applied to the surfaces of other components of a catheter assembly, components attached to the catheter assembly, or other medical devices which may come in direct contact with the patient&#39;s vasculature or in contact with a fluid that may enter the patient&#39;s vasculature. Further, some devices or components are made of a material that is impregnated with an antimicrobial agent. 
         [0005]    Although these techniques have been beneficial, there are various drawbacks that limit their usefulness. For example, it can be difficult and/or expensive to apply an antimicrobial coating or lubricant to the complex internal and external geometries of many devices or components. Also, some devices or components are preferably made of a material that is not suitable for the application of an antimicrobial coating or that cannot be impregnated with an antimicrobial agent. Because of such difficulties, the current techniques for providing antimicrobial protection are oftentimes not used or, if used, are not adequately applied to provide maximum antimicrobial protection. 
         [0006]    Catheters with side ports (commonly referred to as ported catheters) are oftentimes used because additional bolus medications can be easily injected into the catheter adapter via the side port. An example of a typical ported catheter  100  is shown in  FIGS. 1A-1C . As shown, ported catheter  100  comprises a catheter adapter  101  having a side port  103  and a catheter  102  that extends from the distal end of the catheter adapter. A valve for the side port  103  is commonly formed using a piece of tubing  104  positioned within the inner lumen  101   a  of the catheter adapter  101 . The piece of tubing  104  is made of a resilient material and has an external diameter at least as large as the inner diameter of the inner lumen  101   a  so that the tubing  104  seals the inner lumen  101   a  from the side port  103 . 
         [0007]      FIG. 1B  illustrates how tubing  104  is displaced to open a flowpath through the side port  103  into the inner lumen  101   a.  As shown, a separate device  105  (e.g. a luer connector) can be inserted into side port  103 . Fluid can then be expelled from device  105 . The pressure built up within side port  103  as the fluid is injected into side port  103  causes tubing  104  to collapse inwardly as shown in  FIG. 1B . The inward collapse of tubing  104  creates the flowpath through which fluid may flow from device  105  and into lumen  101   a  as indicated by the arrow. 
         [0008]    Various problems exist with this type of ported catheter. For example, as the fluid is ejected from device  105  and prior to tubing  104  collapsing, a substantial amount of pressure can build within side port  103 . This pressure is necessary to cause tubing  104  to collapse. However, in some instances, if the pressure becomes too high, it can cause device  105  to separate from side port  103  allowing fluid to spray out from side port  103 . 
         [0009]    Another problem that exists with common ported catheters is that, after fluids are injected via side port  103 , some residual fluid will remain within side port  103  on top of tubing  104 .  FIG. 1C  represents the state of the ported catheter  100  after device  105  has been removed from side port  103 . As shown, once fluid is no longer injected from device  105 , the lack of pressure will allow tubing  104  to snap back to its original position thereby sealing the opening into inner lumen  101   a.  When this occurs, fluid  106  remains within side port  103 . This residual fluid  106  cannot effectively be removed from side port  103 . If side port  103  is not sealed after use, fluid  106  can quickly become contaminated. Then, when side port  103  is again used for infusion, the contaminated fluid  106  will be flushed into lumen  101   a  and ultimately into the patient thereby increasing the risk of infection. 
         [0010]    A further problem that exists with common ported catheters is that they only allow for fluid flow in a single direction. Because external pressure from fluid flowing into lumen  101   a  is required to cause tubing  104  to collapse inwardly to open the flowpath, it is not possible to have fluid within inner lumen  101   a  (e.g. a patient&#39;s blood) flow out through side port  103 . 
       BRIEF SUMMARY OF THE INVENTION 
       [0011]    The present invention extends to an actuator for a side port of a ported catheter and to ported catheters that contain actuators within their side ports. These actuators can be comprised of a material or contain a coating that elutes an antimicrobial agent when the actuator comes in contact with a fluid. Therefore, any residual fluid that remains within the side port after infusion can be disinfected by the antimicrobial agent eluted from the actuator. 
         [0012]    The use of an actuator in the side port also facilitates bidirectional fluid flow through the side port. The actuator can be configured to open a flowpath when an external device is inserted into the side port. Accordingly, the flowpath can be opened without requiring the presence of built-up pressure within the side port. 
         [0013]    In one embodiment, the present invention is implemented as a ported catheter. The ported catheter comprises a catheter adapter having an inner lumen; a catheter extending distally from the catheter adapter; a side port forming an opening through a sidewall of the catheter adapter into the inner lumen; tubing positioned within the inner lumen to cover the opening formed by the side port; and an actuator contained within the side port. The actuator is configured to compress the tubing inwardly when a device is inserted into the side port. The inward compression of the tubing opens a flowpath from the side port into the inner lumen. 
         [0014]    In another embodiment, the present invention is implemented as a ported catheter comprising: a catheter adapter having a distal opening, a proximal opening, and a lumen that extends between the distal and proximal openings; a side port forming a sidewall opening into the lumen; tubing contained within the lumen and forming a seal over the sidewall opening; and an actuator contained within the side port. The actuator is configured to compress the tubing to open a fluid pathway through the sidewall opening. 
         [0015]    In another embodiment, the present invention is implemented as a ported catheter comprising: a catheter adapter having a distal opening, a proximal opening, and a lumen that extends between the distal and proximal openings; a side port forming a sidewall opening into the lumen; tubing contained within the lumen and forming a seal over the sidewall opening; and an actuator for defeating the seal. The actuator is contained within the side port and comprises one or more antimicrobial agents that elute into a fluid when the fluid contacts the actuator. 
         [0016]    This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter. 
         [0017]    Additional features and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by the practice of the invention. The features and advantages of the invention may be realized and obtained by means of the instruments and combinations particularly pointed out in the appended claims. These and other features of the present invention will become more fully apparent from the following description and appended claims, or may be learned by the practice of the invention as set forth hereinafter. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0018]    In order to describe the manner in which the above-recited and other advantages and features of the invention can be obtained, a more particular description of the invention briefly described above will be rendered by reference to specific embodiments thereof which are illustrated in the appended drawings. Understanding that these drawings depict only typical embodiments of the invention and are not therefore to be considered to be limiting of its scope, the invention will be described and explained with additional specificity and detail through the use of the accompanying drawings in which: 
           [0019]      FIGS. 1A-1C  illustrate a cross-sectional view of a prior art ported catheter. The prior art ported catheter includes tubing within the lumen of the catheter that is compressed inwardly when sufficient pressure is built up within the side port. 
           [0020]      FIGS. 2A-2C  illustrate a cross-sectional view of a ported catheter in accordance with one or more embodiments of the present invention. The ported catheter in accordance with embodiments of the present invention includes an actuator that compresses the tubing when a device is attached to the side port. 
           [0021]      FIGS. 3A-3C  illustrate detailed views of the actuator shown in  FIGS. 2A-2C  respectively. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0022]    The present invention extends to an actuator for a side port of a ported catheter and to ported catheters that contain actuators within their side ports. These actuators can be comprised of a material or contain a coating that elutes an antimicrobial agent when the actuator comes in contact with a fluid. Therefore, any residual fluid that remains within the side port after infusion can be disinfected by the antimicrobial agent eluted from the actuator. 
         [0023]    The use of an actuator in the side port also facilitates bidirectional fluid flow through the side port. The actuator can be configured to open a flowpath when an external device is inserted into the side port. Accordingly, the flowpath can be opened without requiring the presence of built-up pressure within the side port. 
         [0024]    In one embodiment, the present invention is implemented as a ported catheter. The ported catheter comprises a catheter adapter having an inner lumen; a catheter extending distally from the catheter adapter; a side port forming an opening through a sidewall of the catheter adapter into the inner lumen; tubing positioned within the inner lumen to cover the opening formed by the side port; and an actuator contained within the side port. The actuator is configured to compress the tubing inwardly when a device is inserted into the side port. The inward compression of the tubing opens a flowpath from the side port into the inner lumen. 
         [0025]    In another embodiment, the present invention is implemented as a ported catheter comprising: a catheter adapter having a distal opening, a proximal opening, and a lumen that extends between the distal and proximal openings; a side port forming a sidewall opening into the lumen; tubing contained within the lumen and forming a seal over the sidewall opening; and an actuator contained within the side port. The actuator is configured to compress the tubing to open a fluid pathway through the sidewall opening. 
         [0026]    In another embodiment, the present invention is implemented as a ported catheter comprising: a catheter adapter having a distal opening, a proximal opening, and a lumen that extends between the distal and proximal openings; a side port forming a sidewall opening into the lumen; tubing contained within the lumen and forming a seal over the sidewall opening; and an actuator for defeating the seal. The actuator is contained within the side port and comprises one or more antimicrobial agents that elute into a fluid when the fluid contacts the actuator. 
         [0027]      FIGS. 2A-2C  illustrate an example of a ported catheter  200  that employs an actuator  210  to open and disinfect the side port  203  of the ported catheter.  FIGS. 3A-3C  illustrate detailed views of the actuator  210  within side port  203  and correspond to  FIGS. 2A-2C  respectively. As shown, ported catheter  200  comprises a catheter adapter  201  having an inner lumen  201   a.  A side port  203  extends from the catheter adapter  201  and forms an opening into the inner lumen  201   a.  This opening is sealed by a piece of tubing  204  positioned within the inner lumen  201   a  as was described with reference to  FIGS. 1A-1C . 
         [0028]    Unlike ported catheter  100 , ported catheter  200  includes an actuator  210  positioned within side port  203 . As better shown in  FIG. 3A , actuator  210  comprises a bottom portion  210   a  having a diameter that is smaller than the diameter of the opening within side port  203  (shown as  305  in  FIG. 3 ) and a top portion  210   b  having a diameter that is larger than the diameter of the opening within side port  203 . Actuator  210  also includes a lumen  210   c  through which fluid may flow. As best shown in  FIGS. 3A and 3B , side port  203  can include ridges  310  (forming opening  305 ) which prevent actuator  210  from passing completely through opening  305 . 
         [0029]    Referring now to  FIGS. 2B and 3B , when a device  205  is inserted into side port  203 , the tip of device  205  can force actuator  210  against tubing  204  causing tubing  204  to collapse inwardly. As best seen in  FIG. 3B , the collapsing of tubing  204  creates a flowpath through actuator  210  and into lumen  201   a.  In some embodiments, the bottom portion  210   a  can include one or more channels or openings (in addition to the opening formed by lumen  210   c ) through which fluid may pass out from actuator  210  and into lumen  201   a.  For example, the bottom portion  210   a  can include one or more channels that extend upwardly from the bottom tip or one or more holes through the bottom portion  210   a.    
         [0030]    It is noted that the collapsing of tubing  204  can be accomplished entirely from the force applied by actuator  210  to tubing  204  and therefore no fluid pressure needs to be built up to cause tubing  204  to collapse. For this reason, the use of actuator  210  minimizes the likelihood that any fluid will be sprayed out from side port  203 . 
         [0031]    Additionally, because the flowpath around tubing  204  is formed by actuator  210  and not by pressure built-up within side port  203 , the use of actuator  210  allows fluid to flow bidirectionally within side port  203 . In other words, because actuator  210  will maintain the flowpath from side port  203  into lumen  201   a  even when no fluid is flowing out from device  205 , device  205  can be used to collect fluid from within lumen  201   a.  For example, if device  205  is a syringe, the syringe can be used to collect blood from within lumen  201   a.    
         [0032]    In some implementations, side port  203  and/or device  205  can be modified (not shown) to allow device  205  to be interlocked within side port  203 . This may be desired in situations where fluid will be injected from device  205  at high pressure to prevent the forces generated by the high pressure injection (i.e. forces caused when the fluid exists device  205 ) from causing device  205  to back out from side port  203 . However, in many implementations, no locking between device  205  and side port  203  is required because the flowpath created when actuator  210  compresses tubing  204  enables fluid flow without the buildup of pressure. 
         [0033]    Referring now to  FIGS. 2C and 3C , once the injection of fluid has been completed and device  205  has been removed from side port  203 , the resiliency of tubing  204  will cause tubing  204  to return to its original position thereby forcing actuator  210  back out of lumen  201   a.  At this point, tubing  204  again forms a seal between lumen  201   a  and side port  203 . Once this seal is formed, residual fluid  206  will remain within side port  203 . Actuator  210  can be configured so that it remains positioned within side port  203  and particularly within opening  305 . In this position, actuator  210  will be in contact with residual fluid  206  as shown in  FIGS. 2C and 3C . Various techniques can be employed to maintain actuator  210  within side port  203  such as by forming ridges, channels, or other structure within side port  203  and/or actuator  210  that limit the upward movement of actuator  210 . 
         [0034]    In some embodiments of the invention, actuator  210  can be comprised of a material or contain a coating that elutes antimicrobial agents when actuator  210  is in contact with a fluid. In such cases, as fluid  206  contacts actuator  210 , the antimicrobial agent contained within or on actuator  210  will elute into fluid  206  thereby maintaining the sterility of fluid  206  as well as the sterility of surfaces within side port  203 . By maintaining the sterility of side port  203 , the likelihood that microbes will be introduced through side port  203  during a subsequent infusion is reduced. 
         [0035]    Antimicrobial actuators in accordance with one or more embodiments of the invention can be comprised of a base material matrix and one or more antimicrobial agents. In some embodiments, the base material matrix can be a UV curable, hydrophilic material that contains an antimicrobial agent with controlled release (elution) characteristics. Alternatively, a base material can be coated with an antimicrobial coating from which an antimicrobial agent will elute when subject to a fluid. Examples of materials that could be used to form the antimicrobial actuator of the present invention include those disclosed in U.S. Pat. No. 8,512,294 titled Vascular Access Device Antimicrobial Materials And Solutions; U.S. patent application Ser. No. 12/397,760 titled Antimicrobial Compositions; U.S. patent application Ser. No. 12/476,997 titled Antimicrobial Coating Compositions; U.S. patent application Ser. No. 12/490,235 titled Systems And Methods For Applying An Antimicrobial Coating To A Medical Device; and U.S. patent application Ser. No. 12/831,880 titled Antimicrobial Coating For Dermally Invasive Devices. Each of these patent documents is incorporated herein by reference. 
         [0036]    In one particular embodiment, the antimicrobial agent used to form an actuator can be chlorhexidine including chlorhexidine diacetate (CHA) and chlorhexidine gluconate (CHG). However, any other antimicrobial agent that will elute from a base material or from a coating on a base material could be used. Any material having elution characteristics can be employed as the base material of an actuator. Examples of suitable materials include UV cured acrylate-urethanes and heat-cured polymers which soften in water, such as hygroscopic polyurethanes. Also, if an antimicrobial lubricant is employed to provide antimicrobial agents, the actuator can be formed of any suitable material on which the lubricant can be applied whether or not it provides elution characteristics. 
         [0037]    The amount of antimicrobial agent employed within a base material matrix or a lubricant coating can be varied to provide a desired mechanical property or elution characteristic. For example, in some instances a matrix is provided which comprises solid antimicrobial agent particles in an amount representing approximately 0.1-40% w/w of the matrix. These particles may range in size from 100 nm (fine powder) to 0.15 mm (salt-sized crystals). Additional additives may also be used to attain a particular characteristic. These additional additives include: multiple antimicrobial agents to widen the spectrum of microbes that will be affected; viscosity modifiers such as silica; color modifiers such as dyes or titanium dioxide; strength or stiffness modifiers such as glass fibers, ceramic particles such as zirconia, or metallic fibers; radiopacity modifiers such as barium sulfate; and magnetic susceptibility enhancers such as gadolinium chelates. 
         [0038]    In some embodiments, a matrix can be used to form a coating on another material of the actuator. In such cases, the matrix can comprise 9% chlorhexidine diacetate (or chlorhexidine gluconate) mixed in a UV-curable acrylate adhesive (e.g. mCAST 7104 manufactured by Electronic Materials, Inc. or Breckenridge, Colo.). 
         [0039]    In embodiments where a lubricant coating containing the antimicrobial agent is used, the lubricant coating can comprise 9% chlorhexidine diacetate or chlorhexidine gluconate mixed with MED-460 silicone lube. The viscosity of the lube can be modified by adding fumed silica in concentrations up to 3%. The use of 9% chlorhexidine represents specific examples; however, other percentages could equally be used to provide a desired elution duration. 
         [0040]    To summarize, an antimicrobial actuator in accordance with one or more embodiments of the invention can be molded out of any material and then coated with an antimicrobial eluting coating or lubricant, or can be cast or formed out of a base material matrix that incorporates the antimicrobial agent. Regardless of how the actuator is formed or the materials used to form it, an actuator in accordance with the present invention can elute antimicrobial agents into fluid to sterilize or maintain the sterility of the fluid and contacting surfaces. 
         [0041]    Because actuator  210  can include antimicrobial agents to sterilize fluid contained within side port  203 , the present invention minimizes the likelihood of infection when ported catheter  200  is used. In some embodiments, when side port  203  is not in use, a cap or other cover can be placed over side port  203  to prevent contaminants from entering side port  203 . However, because actuator  210  can provide antimicrobial benefits, a cap or other cover may not be required or may not need to provide any level of antimicrobial protection to side port  203 . Accordingly, actuator  210  can facilitate the aseptic use of a ported catheter. 
         [0042]    The present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative and not restrictive. The scope of the invention is, therefore, indicated by the appended claims rather than by the foregoing description. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope.