Abstract:
A valved catheter assembly is designed to be used to minimize patient discomfort and to prevent infection at an entry site. The valved catheter assembly includes a hub including a slit valve disposed therein and distal tubing extending in a distal direction from the hub when the valved catheter assembly is inserted into a body of a patient. The valved catheter assembly is free of proximal tubing extending in a proximal direction from the hub.

Description:
TECHNICAL FIELD  
         [0001]    This invention relates to a valved catheter. More particularly, this invention relates to a catheter including a valve disposed within a hub.  
         BACKGROUND INFORMATION  
         [0002]    Intravenous catheters are long, soft tubular members that deliver fluids to a patient&#39;s blood stream. A peripherally inserted central catheter (PICC) is a particular type of intravenous catheter that is inserted into a patient&#39;s vein at an entry site, such as, for example, an entry site located near the bend of the patient&#39;s right arm. A medical professional, such as a physician or nurse, guides a distal tip of the PICC through the patient&#39;s vein and positions the distal tip at a predetermined cardiac site, such as, for example, the right atrium of the patient&#39;s heart.  
           [0003]    Once properly positioned within the patient&#39;s body, a portion of the PICC extends from the entry site and is external to the patient&#39;s body. This portion of the PICC is generally about five centimeters to about twenty centimeters long and is accessible to the medical professionals to provide the patient with intravenous treatments, such as, for example, to deliver medications, fluids, nutritional supplements, blood and blood products, as well as to withdraw blood for laboratory tests.  
           [0004]    A hub disposed on the tubular member of the PICC near the entry site secures the external portion of the PICC to the patient&#39;s body. Typically, a clamp positioned on the external portion of the PICC is used to prevent leakage in between intravenous treatments.  
         SUMMARY OF INVENTION  
         [0005]    The present invention generally relates to peripherally inserted central catheters. Devices according to the invention are typically used to deliver fluids directly to a patient&#39;s blood stream. It is an object of this invention to provide a device that allows fluid access to a predetermined cardiac site while, at the same time, minimizes patient discomfort and infection at an entry site. It is another aspect of the invention to provide a device that extends externally from the entry site less than about 3.81 centimenters.  
           [0006]    In one aspect, the invention relates to a valved catheter assembly. The valved catheter assembly includes a catheter and a hub. The catheter includes a distal end including an opening, a proximal end, and at least one lumen extending therethrough. The hub is attached to the proximal end of the catheter. The hub includes a distal portion defining a lumen extending therethrough, a proximal portion also defining a lumen extending therethrough and including a luer proximal end. The hub also includes a flexible, thin disk including a slit. The flexible, thin disk is disposed within the hub such that a portion of the flexible, thin disk is in contact with the proximal portion of the hub and the slit is substantially perpendicular to a longitudinal axis of the hub. The valved catheter assembly is sized such the catheter spans a distance commensurate with a distance from a predetermined cardiac site to an entry site in the patient&#39;s skin.  
           [0007]    Embodiments of this aspect of the invention can include the following features. In one embodiment, the distal portion of the hub includes a suture wing. In some embodiments, the valved catheter assembly further includes a transparent dressing positioned over the hub and entry site. In other embodiments, the hub is secured to the patient&#39;s skin. In one embodiment, the hub is situated immediately adjacent to the entry site.  
           [0008]    In another aspect, the invention relates to a valved catheter assembly including a hub and distal tubing. The hub includes a distal end, a luer proximal end, and a valved disposed therebetween. The distal tubing extends in a distal direction from the distal end of the hub and the leur proximal end of the hub is free of proximal tubing.  
           [0009]    Embodiments of this aspect of the invention can include the following features. In one embodiment, the distal end of the hub includes a suture wing. In some embodiments, the hub is secured to a patient&#39;s skin. In other embodiments, the valved catheter assembly further includes a transparent dressing positioned over the hub and entry site.  
           [0010]    In another aspect, the invention relates to a valved catheter assembly including a hub and a catheter. The hub includes a slit valve disposed therein. The catheter is disposed distal to the hub and in fluid communication with the hub. The catheter includes a distal end, a proximal end and a tubular element extending between the distal and proximal ends and wherein the tubular element is free of a clamp disposed thereon.  
           [0011]    Embodiments of this aspect of the invention can include the following features. In one embodiment, the distal end of the hub includes a suture wing. In some embodiments, the hub is secured to a patient&#39;s skin. In other embodiments, the valved catheter assembly further includes a transparent dressing positioned over the hub and entry site.  
           [0012]    In general, in another aspect, the invention relates to a method of delivering fluids to a patient. The method, according to this aspect of the invention, includes providing a valved catheter assembly described above, inserting the valved catheter assembly into the patient&#39;s body through an entry site, and attaching the luer proximal end to tubing adapted for delivering fluids to the valved catheter assembly. In one embodiment of this aspect of the invention, the method can further include a step of measuring a distance spanning between the patient&#39;s right atrium and the entry site and then trimming the distal tubing to a length substantially equal to said distance prior to inserting the valved catheter assembly into the patient&#39;s body.  
           [0013]    The foregoing and other objects, aspects, features, and advantages of the invention will become more apparent from the following description and the claims. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0014]    In the drawings, like reference characters generally refer to the same parts throughout the different views. Also, the drawings are not necessarily to scale, emphasis instead generally being placed upon illustrating the principles of the invention.  
         [0015]    [0015]FIG. 1 is a schematic view of one embodiment of a prior art peripherally inserted central catheter.  
         [0016]    [0016]FIG. 2 is a schematic view of the prior art peripherally inserted central catheter of FIG. 1 inserted within a patient&#39;s body.  
         [0017]    [0017]FIG. 3 is a schematic view of one exemplary embodiment of a peripherally inserted central catheter according to the invention.  
         [0018]    [0018]FIG. 4 is an exploded view of a portion of the peripherally inserted central catheter labeled A in FIG. 3.  
         [0019]    [0019]FIG. 5 is a schematic view of one exemplary embodiment of an internal valve located within the portion of the peripherally inserted central catheter shown in FIG. 4.  
         [0020]    [0020]FIG. 6 is a schematic view of the peripherally inserted central catheter of FIG. 3 inserted within a patient&#39;s body. 
     
    
     DESCRIPTION  
       [0021]    Intravenous catheters are used to transport fluids, such as, medications, nutritional supplements, and blood to a patient&#39;s blood stream. Peripherally inserted central catheters (PICC) are a type of intravenous catheters that are inserted into a vein within the patient&#39;s right arm. Generally, the PICC is used for multiple intravenous treatments and once positioned within the patient body, a PICC can be left in place up to about six months. In between treatments a clamp positioned on an external portion of the PICC prevents leakage from the PICC.  
         [0022]    [0022]FIG. 1 shows an illustrative prior art PICC  1 . The prior art PICC  1  includes a catheter (tubular member)  2 , a hub  8 , and proximal tubing  18 . The catheter  2  is the portion of the PICC  1  that is insertable into a patient&#39;s body. The hub  8  and the proximal tubing  18  remain external to a patient&#39;s body while the prior art PICC  1  is in use.  
         [0023]    The catheter  2  extends between a distal end  4  to a proximal end  6 . The distal end  4  is open and is in fluid communication with a lumen extending within the catheter  2 . The proximal end  6  is also in fluid communication with the lumen and is secured to a hub  8 . The hub  8  includes a distal portion  10  and a proximal portion  12 . Disposed between the distal portion  10  and proximal portion  12  are a pair of suture wings  14  that help to secure the hub  8  to the patient&#39;s body via suture openings  16 .  
         [0024]    Extending from the proximal portion  12  of the hub  8  is proximal tubing  18 . The proximal tubing  18  has a length long enough to support a clamp  20  and generally has a length ranging between about 3.81 centimeters (1.5 inches) to about 15.24 centimeters (6 inches). The clamp  20  when activated collapses a lumen extending through the proximal tubing  18 , thereby limiting leakage from the prior art PICC  1 .  
         [0025]    At a proximal end  22  of the proximal tubing  18  is a luer end cap  24 . During medical treatments the lumen extending through the proximal tubing  18  is open and the luer end cap  24  is connected to a fluid introduction source, such as, for example, an intravenous bag, a cannula, or a syringe.  
         [0026]    Referring to FIG. 2, the prior art PICC  1  is introduced into a patient&#39;s body  30  through an entry site  34  located just above a bend in the patient&#39;s right arm. Other entry sites, such as, for example, the groin, neck, and back of the patient are also available sites to introduce the prior art PICC  1 . A medical professional guides the distal tip  4  of the catheter  2  from the entry site  34  through the patient&#39;s vein until the distal tip  4  is positioned within the right atrium of the patient&#39;s heart  32 . The medical professional then secures the prior art PICC  1  to the patient&#39;s body via the hub  8 . Once secured, the external portion of the PICC  1  (the hub  8 , proximal tubing  19 , clamp  20 , and luer end cap  24 ) extends about 5.08 centimeters (2 inches) to about 20.32 centimeters (8 inches) from the entry site  34 .  
         [0027]    One of the problems with the prior art PICC  1  is that the proximal tubing  18  in combination with the clamp  20  and luer end cap  24  can be irritating to the patient&#39;s skin. Also, the length of the external portion (about 2 inches to about 8 inches) is awkward and inhibits the patient&#39;s free movement. Another problem with the prior art PICC  1  is that the clamp  20  does not satisfactorily close the lumen extending through the proximal tubing  18 , resulting in leakage and infection at the entry site  34 .  
         [0028]    [0028]FIG. 3 shows an exemplary embodiment of a PICC  50  manufactured in accordance with the teachings of the present invention. The PICC  50  includes a catheter (distal tubing)  52  and a valved hub  58 . The catheter  52  has an open distal end  54 , a proximal end  56 , and a lumen extending from the proximal end  56  to the open distal end  54 .  
         [0029]    Attached to the proximal end  56  of the catheter is the valved hub  58 . When the PICC  50  is in use, the valved hub  58  remains external to the patient&#39;s body. Referring to FIGS. 3-5, the valved hub  58  includes a distal portion  60 , a proximal portion  62 , and a flexible, thin disk  70  including a slit  75  (slit valve). Each of the distal and proximal portions  60 ,  62  define a lumen extending therethrough. The proximal portion  62  can include a luer proximal end  68  for attaching the PICC  50  to a fluid introduction source.  
         [0030]    Disposed within the valved hub  58  between the distal and proximal portions  60 ,  62  is the flexible, thin disk  70  including the slit  75 . The flexible, thin disk  70  with the slit  75  is used as a valve, which opens and closes depending on a pressure differential across the slit  75 . For example, if the pressure differential between the proximal portion  62  and the distal portion  60  is less than a threshold value, the slit  75  within the flexible, thin disk  70  will remain closed, thereby preventing liquid from leaking from the PICC  50 . However, if the pressure differential across the flexible, thin disk  70  is greater than the threshold value, the slit  75  will open and fluid can be transported from the luer proximal end  68  to the distal tip  54  or alternatively, liquid can be transported from the distal tip  54  to the luer proximal end  68 .  
         [0031]    The flexible, thin disk  70  is positioned within the valved hub  58 , such that a portion the flexible, thin disk  70  is in contact with the proximal portion  62  and another portion of the flexible, thin disk  70  is in contact with the distal portion  60  of the valved hub  58 . In addition, when the flexible, thin disk  70  is positioned within the valved hub  58 , the slit  75  is substantially perpendicular to a longitudinal axis L,  80  of the valved hub  58 .  
         [0032]    The flexible, thin disk  70  is typically made from silicone, but other biocompatible, flexible, elastomer materials can be used as well. The slit  75 , shown in FIG. 5 is a latitudinal cut. However in other embodiments, not shown, the slit  75  can have other configurations, such as an “H” shape, or a sinusoidal shape.  
         [0033]    The valved hub  58  can also include a set of suture wings  64  extending off of the distal portion  60 . The suture wings  64  are used to secure the hub  58  to the patient&#39;s body via suture openings  66 . Specifically, the valved hub  58  can be secured by the use of an anchor including two vertical post spaced at a distance corresponding to the distance between the suture openings  66 . The anchor is attached to the patient&#39;s skin via an adhesive pad. Thus, when the posts of the anchor are inserted into the suture openings  66  the valved hub  58  is secured to the skin via the anchor and adhesive pad.  
         [0034]    [0034]FIG. 6 shows the PICC  50  after insertion into the patient&#39;s body  30 . The PICC  50  is inserted into a vein at the entry site  34  located on the patient&#39;s right arm. When properly positioned, the distal end  54  of the catheter is located at a predetermined cardiac site, such as, within the right atrium of the patient&#39;s heart  32 , the catheter  50  is within the patient&#39;s vein, and the valved hub  58  is external to the patient&#39;s body proximal and immediately adjacent to the entry site  34  (e.g., located less than about 3.81 centimeters from the entry site  34 ). Thus, the catheter  50  spans a distance  85  commensurate with a distance from the patient&#39;s right atrium of the heart  32  to the entry site  34 . The entry site  34  shown in FIG. 6 is the patient&#39;s right arm, however other possible entry sites include, for example, the groin, neck, and back. The medical professional can measure radiographically the distance  85  prior to inserting the PICC  50  including catheter  52 . The medical profession can then either select an appropriately sized PICC  50  having a catheter with a length corresponding to distance  85 , or alternatively, the medical profession can trim the catheter  52  to the measured length.  
         [0035]    It is important to note that the PICC  50  does not include proximal tubing extending from the valved hub  58 , nor does PICC  50  include a clamp disposed on the catheter  52 . Thus, the PICC  50  manufactured in accordance with the teachings of the present invention is less likely than the prior art PICC  1  to irritate the patient&#39;s skin, because the PICC  50  does not include proximal tubing that extends about  5 . 08  centimeters (2 inches) to about 20.32 centimeters (8 inches) from the entry site  34 . Instead, the PICC  50  terminates at a distance less than about 3.81 centimeters and typically between about 1 centimeters and about 3 centimeters from the entry site  34 . In some embodiments, it is preferred that the PICC  50  terminates at a distance less than about 2.54 centimeters from the entry site. Thus, PICC  50  is more tolerable to the patient than the awkward 5.08 centimeter to 20.32 centimeter length of the external portion of prior art PICC  1 . In addition, PICC  50  does not include a clamp to impede flow. Instead, the valved hub  58  has an internal valve, the thin, flexible disk  70  including the slit  75 , to regulate flow. Since there is no clamp or proximal tubing extending from the valved hub  58 , the PICC  50  is less irritating to the patient than a similarly inserted prior art PICC  1 .  
         [0036]    To supply fluids to the patient, the medical professional attaches the fluid introduction source to the luer proximal end  68  and then releases fluid from the fluid introduction source. The fluid entering into the proximal portion  62  of the valved hub  58  creates a pressure differential across the flexible, thin disk  70  including the slit  75 . The slit  75  responds to a pressure differential that is above threshold by opening to allow fluids to pass therethrough and into the lumen of the catheter  52 .  
         [0037]    In between treatments, the luer proximal end  68  is free of the fluid introduction source and can be covered with a transparent dressing  90 . The transparent dressing  90  further secures the valved hub  58  to the patient&#39;s body  30 , while at the same time covers and protects both the entry site  34  and the valved hub  58  from infection.  
         [0038]    Variations, modifications, and other implementations of what is described herein will occur to those of ordinary skill in the art without departing from the spirit and scope of the invention. The invention is not to be limited only to the preceding illustrative description.