Abstract:
A single-use, clamshell protective cap for use primarily in healthcare settings in order to maintain the integrity of a medication solution. The cap has two halves, a cylindrical skirt, a puncture resistant lid portion, an interior flange, and an interlocking snap. When placed around a flanged injection port such as is found on a conventional fluid container and closed, the lid portion covers an access site on an injection port. After the cap is placed, the interior flange engages the port flange to prevent upward axial movement relative to the port, thereby preventing removal of the cap and thus deterring unwanted or erroneous drug administrations or withdrawals.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims the benefit of priority to U.S. Provisional Patent Application Ser. No. 60/986,341, filed on Nov. 8, 2007, the entirety of which is hereby incorporated by reference. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    The present invention relates to the field of containers for administering medical fluids to patients. More particularly, the present invention relates to a snap-over clamshell protective port cap for intravenous (IV) fluid containers. 
         [0003]    Access ports are commonly used in infusion solution containers to administer solutions to a patient, or to add medicaments or other solutions to the container prior to administration. Current solution containers typically may include a dedicated outlet port for solution administration to a patient and a dedicated inlet port for the addition of diluent or other ingredients to the container. These ports are conventional in the art and may be of different types of construction but typically have an annular flange. The ports are in fluid communication with the container, usually via an attached tube having a diameter smaller than the port flange. 
         [0004]    The outlet port is intended to be coupled to an administrative set and is therefore commonly referred to as the administrative port, whereas the inlet port is designed to permit the injection of therapeutic agents and nutrients into the partially filled container and is sometimes identified as the additive or injection port. Such a container may contain a partial filling of a sterile solution such as water, saline, dextrose or a combination thereof to function as a diluent for the injected additive. The diluted drug or nutrient is then administered to a patient by means of the administrative set that may be either directly or indirectly (i.e., through another solution set) coupled to the patient. 
         [0005]    Maintaining the integrity of medication solutions to be administered to a patient is of major importance. It has been found, however, that careless or inattentive handling of a solution container may create significant risks of drug administration errors. Such errors include duplicate administrations of the same substance (overdosing) as well as mis-administration of the wrong substance. These risks may be increased where emergency situations are presented that require quick manipulation of the various components and quick addition of one or more substances to a container via the additive port. In extreme circumstances, a person may intentionally seek to harm a patient by adding one or more agents. Likewise, one could deliberately remove properly mixed solutions via the additive port for illicit purposes. It is imperative that evidence of such tampering be readily apparent to caregivers or their supervisors. 
         [0006]    Current methods of making notification of a previous drug administration include placing an adhesive label over the face of the port or onto the container itself. Adhesive labels are not mechanically attached to the port or the container, may be removed, and do not offer any resistance to subsequent needle penetration. 
         [0007]    Therefore, an object of this invention is to provide an additive port cap closure that is readily available and easy to place on a port, fully covering the same, upon the completion of prescribed drug admixtures. 
         [0008]    A further object of the invention is to provide an additive port cap closure that cannot be removed without damaging the cap and/or the underlying port, and/or leaving visible evidence of tampering. 
         [0009]    Another object of the invention is to provide an additive port cap closure that is puncture resistant so as to deter the administration or removal of one or more substances via syringe after the cap is in place. 
         [0010]    Yet another object of the invention is to provide an additive port cap closure that is easy and inexpensive to manufacture. 
         [0011]    These and other objects will be apparent to those skilled in the art. 
       SUMMARY OF THE INVENTION 
       [0012]    A snap-over clamshell protective port cap is provided for use primarily in clinical healthcare settings, such as hospital pharmacies. Specifically, the cap is designed to be placed over an injection or additive port on a conventional IV fluid container or the like. 
         [0013]    In a typical scenario, one or more substances are added to the container through the injection port using a conventional syringe. In order to deter unwanted or erroneous drug administrations or withdrawals, the snap-over port cap is immediately placed over the injection or additive port. The cap is intended for a single use, is disposable and cannot be removed, tampered with or compromised without damaging the cap or at the very least conspicuously stressing or deforming the cap material to give a visible indicator of the disrupting activity. 
         [0014]    The cap comprises two cylindrical halves connected by a hinge. The end of each half cylinder opposite the hinge has a complementary component of an interlocking snap. The first half of the cap comprises roughly one half of a cylindrical skirt, a puncture-resistant, circular lid portion, and a flange, while the second half comprises the remaining one half of the cylindrical skirt and a corresponding flange. In use, an open cap is placed about an injection port such that the injection surface of the port is obscured or covered by the lid portion. The halves are pivoted toward one another about the hinge and the interlocking snap is engaged. 
         [0015]    The diameter of the lid portion is larger than the diameter of the access site about the port, covering that portion of the port utilized for administrations. Upward axial movement relative to the port is deterred by the engagement between the flange on the cap and the flange about the port, and the cap is maintained in place. 
         [0016]    Attempts to forcibly remove the cap from the port will cause visible deformation or destructive change to the cap, particularly to the latch tabs and the hinge, and possibly to the port and/or the container. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0017]      FIG. 1  is a perspective view of a clamshell protective port cap. 
           [0018]      FIG. 2  is a partial cutaway perspective of a clamshell protective port cap. 
           [0019]      FIG. 3  is a perspective view illustrating a clamshell protective port cap being positioned about a conventional port. 
           [0020]      FIG. 4  is a perspective view of a clamshell protective port cap in place about a conventional port. 
           [0021]      FIG. 5  is a top plan view of a clamshell protective port cap in place about a conventional port. 
           [0022]      FIG. 6  is a side plan view of a clamshell protective port cap in place about a conventional port. 
           [0023]      FIG. 7  is a cross-section of a clamshell protective port cap in place about a conventional port, taken along line  7 - 7  of  FIG. 6 . 
           [0024]      FIG. 8  is a partial cross-section illustrating in detail the interlocking structure of the lid portion and skirt portion of the clamshell protective port cap of  FIG. 7 . 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0025]    The embodiments discussed herein are merely illustrative of specific manners in which to make and use the invention and are not to be interpreted as limiting the scope of the instant invention. 
         [0026]    While the invention has been described with a certain degree of particularity, it is to be noted that many modifications may be made in the details of the invention&#39;s construction and the arrangement of its components without departing from the scope of this disclosure. It is understood that the invention is not limited to the embodiments set forth herein for purposes of exemplification. 
         [0027]    Referring to  FIG. 1 , clamshell cap  10  comprises a first half  12  and a second half  14 . It will be understood from the drawings and description that the terms ‘first half’ and ‘second half’ as used herein refer to portions or functional members of cap  10 , and the term ‘half’ in this context is not used in a strict literal sense to mean a given quantity or percentage of cap  10 . First half  12  has a hinge end  16  and a snap end  18 . Second half  14  has a hinge end  20  and a snap end  22 . Hinge  24  is attached to hinge end  16  of first half  12  and hinge end  20  of second half  14 , such that first and second halves  12 ,  14  are hingedly or pivotably attached. Without limitation, “hinge” herein should be interpreted to include any number of conventional hinges or other structural connections that permit hinging or pivoting motion about an axis. First snap portion  26  is attached to snap end  18 . Second snap portion  28  is attached to snap end  22 . First and second snap portions  26 ,  28  may be complementary members of any conventional interlocking snap, many of which are well known in the art. Once interlocked, snap portions  26 ,  28  are substantially permanently interlocked, and are designed such that they cannot be easily unlocked without damage, destruction, or visible evidence of tampering. 
         [0028]    Also considering  FIG. 2 , first half  12  further comprises a cylindrical skirt portion  30 , a roughly circular lid portion  32 , and a flange  34 , the flange  34  extending inwardly from the base  31  of cylindrical skirt portion  30  in a plane essentially parallel to the plane defined by lid portion  32 . Second half  14  comprises a cylindrical skirt portion  36  that is substantially a mirror image of cylindrical skirt portion  30 , and a flange  38  extending inwardly from the base  37  of cylindrical skirt portion  36  that is substantially a mirror image of flange  34 . However, other generally complementary or even cooperative relationships between skirt portions  30 ,  36  will not detract from the invention. 
         [0029]    As shown in  FIG. 3 , conventional solution container  40  has an inlet port  42 , an access site  44  on inlet port  42 , an inlet tube  46 , an outlet tube  48  and an outlet port  50 . Access site  44  is typically centrally located about inlet port  42  and commonly referred to as a reseal element or reseal member; ‘access site’ is used herein to denote that portion of the port through which substances are administered, without limitation. Situated about inlet port  42  is annular flange  52 . 
         [0030]    In use, first half  12  of open cap  10  is placed about an injection port  42  such that the injection surface or access site  44  of port  42  is obscured or covered by lid portion  32 , and flange  34  is situated about an equivalent circumference of injection port flange  52  and is partially around inlet tube  46 . Still referring to  FIG. 3 , cap  10  is positioned such that by moving cap  10  in the direction of arrow  53 , lid portion  32  will cover injection surface  44 . Alternatively, second half  14  of open cap  10  is placed about injection port  42  such that flange  38  is situated about an equivalent circumference of injection port flange  52  and is partially around inlet tube  46 . 
         [0031]    In the first instance, as illustrated in  FIG. 4 , second half  14  is folded toward first half  12  about hinge  24 , in the direction of arrow  55  and over injection port  42 , so that second snap portion  28  engages first snap portion  26 . It will be appreciated that in the second instance, first half  12  is folded toward second half  14  about hinge  24 , over injection port  42 , so that first snap portion  26  engages second snap portion  28 . Upon engagement of interlocking snap portions  26 ,  28 , a closed cap  10  is provided. It should be understood that no limitation is intended herein as to whether a particular half should or could be applied to the port first, or whether open cap  10  should or could be centered about a port (i.e., neither half is positionally favored) prior to closing. 
         [0032]    Turning to  FIGS. 5 and 6 , in a closed position about injection port  42  (not visible), cylindrical skirt portions  30 ,  36  ( FIGS. 1 and 2 ) of cap  10  are complementary and meet to form a closed cylindrical skirt  54 . Likewise, as can be understood in view of  FIGS. 1 ,  2 ,  5 ,  6  and  7 , flange  34  and flange  38  of cap  10  are complementary and when cap  10  is closed meet at their respective ends, forming a closed annular flange  56 . Closed annular flange  56  defines an inner aperture smaller in diameter than lid portion  32  and flange  52  about injection port  42 , but larger in diameter than inlet tube  46 . Unlike various protective caps known in the art, the interior of cap  10  between lid portion  32  and closed annular flange  56  is devoid of gripping members such as teeth or ridges that engage injection port  42 . 
         [0033]    When closed, cap  10  may rotate freely about injection port  42 , but closed annular flange  56  prevents cap  10  from being axially removed from injection port  42 . Cylindrical skirt  54  is constructed of a substantially rigid material, such as polypropylene or suitable plastic. Lid portion  32  is also constructed of a rigid material, such as polypropylene or suitable plastic, and is preferably of sufficient thickness to provide puncture resistance to conventional clinical needles. Cap  10  may be molded as a unitary piece using conventional techniques. 
         [0034]    The diameter of lid portion  32  is larger than the diameter of access site  44 , such that when cap  10  is in place, lid portion  32  fully covers access site  44 . Lid portion  32  is preferably unitary or of one-piece construction, such that there are no gaps, spaces or seams about that portion of lid portion  32 , generally the center, that corresponds to access site  44  of injection port  42 . 
         [0035]    Approximately one half of the circumference of lid portion  32  adjoins first cylindrical skirt portion  30  of first half  12 . The remaining approximate one half of the circumference of lid portion  32  extends in a cantilevered manner from the first-mentioned portion and is free from (i.e., does not adjoin) skirt portion  30 . This free circumference  58  is preferably beveled, as shown in  FIG. 1 . The end  60  of second cylindrical skirt portion  36  of second half  14  opposite of flange  38  is also beveled, as shown in  FIG. 1 . 
         [0036]    Beveled circumference  58  of lid portion  32  and beveled end  60  of second cylindrical skirt portion  36  interlock when first half  12  and second half  14  are closed about hinge  24 . In one embodiment, shown in cross-section in  FIG. 7 , beveled end  60  and beveled circumference  58  each have a corresponding vertical portion  62  adjacent, and in addition, to the provided bevel. It will be appreciated that the combination of the bevel and vertical portion  62  enhances the interlocking between lid portion  32  and second cylindrical skirt portion  36 . Furthermore, directing the bevel away from access site  44  of injection port  42  helps to ensure that cap  10  cannot be compromised, for example by needle penetration at the junction between lid and skirt. Although straight vertical complementary portions are shown in  FIG. 7 , other shapes and orientations can be used, including but not limited to curves, radiuses, and non-vertical straight or undulating surfaces. 
         [0037]    Optionally, as shown in  FIG. 7  and in detail in  FIG. 8 , a rib  66  on second cylindrical skirt portion  36  projects inwardly adjacent to and below vertical portion  62 . Beveled end  60 , vertical portion  62 , and rib  66  on skirt portion  36  together define a notch  68  that receives, more preferably guides, and most preferably mates with beveled circumference  58  of lid portion  32 . Rib  66  also helps support circumference  58 . Thus, lid portion  32  can be brought into proper engagement with skirt portion  36  despite minor waviness or variations in alignment or orientation of lid portion  32  due to molding. In one embodiment, rib  66  is provided with a beveled upper surface at its inward leading edge. This facilitates the engagement of circumference  58  and the guidance of circumference  58  into notch  68 . 
         [0038]    Once all desired medications, drugs and other substances have been added to container  40  in any conventional manner, cap  10  is placed over injection port  42  with lid portion  32  facing outward and with the interior of cap  10  facing injection port  42 . Thereafter, removal of cap  10  is deterred due to interference between closed annular flange  56  and flange  52  about injection port  42 . 
         [0039]    Referring back to  FIGS. 6 and 7 , it should be appreciated that if one attempts to remove cap  10  by applying axial pulling force in the direction of arrow  64 , closed annular flange  56  will engage flange  52  and deter further axial movement. Rotational movement of cap  10  about injection port  42  is possible, but this is not a limitation. Depending upon the structure of injection port  42  and/or the thickness of flange  52 , cap  10  may or may not freely rotate. 
         [0040]    Snap portions  26 ,  28  serve as tensile stress concentrators. Attempts to forcibly open cap  10  will result in the fracture of one or both snap portions  26 ,  28  or at the very least cause a visible deformation of one or more portions of snap portions  26 ,  28 , as well as closed cylindrical skirt  54 . Deformations could include, but are not limited to, discoloration, stressing, and creasing. Likewise, persons skilled in the art will appreciate that attempts to pry cap  10  away from injection port  42  will result in deformations to cap  10 , and could additionally result in deformations and/or destructive changes to injection port  42 , inlet tube  46  or even container  40 . 
         [0041]    Caps  10  may be color coded to facilitate identification of certain types of medical solutions. For example, red caps may be provided for hazardous agents such as oncolytics, while purple caps may be provided for general drug administrations. Persons skilled in the art will appreciate that there are a number of color-coding conventions in the clinical setting, and that there are potentially limitless color combinations. 
         [0042]    Whereas, the present invention has been described in relation to the drawings attached hereto, it should be understood that other and further modifications, apart from those shown or suggested herein, may be made within the scope of this invention.