Abstract:
A medical instrument sterilization container ( 10 ) is provided which includes a port ( 18 ). A removable filter ( 32 ) is received within port ( 18 ) to enable sterilization of instruments placed within container ( 10 ). A removable plug ( 48 ) replaces filter ( 32 ) to enable container ( 10 ) to be used to transport instruments without leaking of fluids therefrom.

Description:
This application is a divisional of U.S. Ser. No. 09/388,162, filed Jun. 22, 1999 by Robert T. Nichols, William H. Patterson and Keith F. Lindsey, and entitled Contaminant Plug for Medical Instrument Sterilization Containers, now U.S. Pat. No. 6,145,687 dated Nov. 14, 2000, which is a continuation of U.S. Ser. No. 08/455,201, filed May 31, 1995, now U.S. Pat. No. 5,954,219 dated Sep. 21, 1999, which is a divisional of U.S. Ser. No. 08/140,215, filed Oct. 21, 1993, now U.S. Pat. No. 5,474,738 dated Dec. 12, 1995, which is a continuation of U.S. Ser. No. 07/664,352 filed Mar. 4, 1991, now U.S. Pat. No. 5,324,489 dated Jun. 28, 1994. 
    
    
     TECHNICAL FIELD OF THE INVENTION 
     The present invention relates generally to the field of medical instrument sterilization containers, and more particularly to a contaminant plug for medical instrument sterilization containers. 
     BACKGROUND OF THE INVENTION 
     It is common practice in hospitals and other medical environments to sterilize medical instruments with steam or other sterilizing gases such as ethylene oxide (ETO). Sterilization containers provide a convenient enclosure in which the sterilization can be performed. Additionally, sterilization containers can be used as a storage and containment device for moving contaminated instruments from one location to another, while reducing the probability of cross-contaminating the surrounding environment. Finally, during the transfer of contaminated instruments after surgery, sterilization containers can also be used for soaking medical instruments to prevent blood and other contaminants from drying on the instruments. 
     Sterilization containers normally have bottom housings with a bottom and sidewalls, removable lids, ports for the passage of sterilization gases and filter means for preventing and inhibiting contaminants from entering the container after sterilization. Containers generally have one or two ports in the lid and one or two ports in the bottom. Both top and bottom ports are needed if the container is to be used for gravity steam or ethylene oxide gas sterilization. In gravity steam processes, steam gases enter the top of the sterilizing container and push air down and out. The lower port is therefore required for air and steam to exit the container. When utilizing ethylene oxide gas sterilization, both top and bottom ports are required during the aeration process in which air is passed through a container to remove residual ethylene oxide gas remaining after sterilization. 
     The need for both top and bottom ports in the gravity steam and ethylene oxide processes reduces the utility of the sterilization container for soaking and transportation applications. If the container is to be utilized as a receptacle for soaking instruments after surgery, or for transporting contaminated instruments, the bottom or outlet ports will create problems. It has been recognized in the medical industry that filtered or open ports in the sterilization container bottom may allow soaking fluids or contaminants to leak or pass through to the outside, thereby contaminating the surroundings. This is even often true with hydrophobic type filters which are generally perceived to pass only gases and not liquids or solids. Even with such hydrophobic type filters, there is still the concern that small amounts of contaminants may seep through the filter or around the seal. 
     The need has therefore arisen for a plug which can seal a container port such that contaminants, whether liquid or solid, cannot escape. Such a plug would allow the use of a medical instrument sterilization container with both top and bottom ports to be used for the transportation of contaminated medical instruments without the fear of contamination of the surroundings. Further, such a plug would allow a medical instrument sterilization container having a bottom port to be used for soaking medical instruments after surgery without leakage. 
     SUMMARY OF THE INVENTION 
     According to the invention, a medical instrument sterilization container is provided which includes a port. A removable filter is provided within the port to enable sterilization of instruments placed within the container. A removable plug is provided which replaces or fits above or below the filter to enable the container to be used to transport instruments placed within the container without permitting the passage of contaminants out of the container. 
     The present invention provides the advantage of sealing a port on a medical instrument sterilization container such that liquid or solid contaminants cannot escape into the surrounding environment. The medical instrument sterilization container can thus be used as a safe means of transporting contaminated medical instruments without cross contamination between the exterior and interior of the container. Further, by sealing a medical instrument sterilization container according to the present invention, the medical instrument sterilization container can be used as a soaking container for soaking instruments following their use. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS. 
     Other aspects of the invention and their advantages will be discerned when one refers to the following detailed description as taken in conjunction with the drawings, in which like numbers identify like parts, and in which: 
     FIG. 1 is a perspective view of a medical instrument sterilization container; 
     FIG. 2 is a partial section view of the sterilization container of FIG. 1; 
     FIG. 3 is an exploded view of a selected port of the medical instrument sterilization container of FIG.  1  and the associated filter and retaining cap; 
     FIGS. 4 a  and  4   b  are top and side views of a contaminant plug according to a first preferred embodiment; 
     FIGS. 4 c  and  4   d  are respectively exploded and cross-sectional views showing the engagement of the contaminant plug of a first preferred embodiment engaging with a selected port of the medical instrument sterilization container of FIG. 1; 
     FIGS. 5 a  and  5   b  are respectively top and side views of a contaminant plug according to a second preferred embodiment; 
     FIGS. 5 c  and  5   d  are respectively exploded and cross-sectional views depicting the contaminant plug of a second preferred embodiment engaging a selected port in the medical instrument sterilization container of FIG. 1; 
     FIGS. 6 a  and  6   b  are respectively top and side views of a contaminant plug according to a third preferred embodiment; and 
     FIGS. 6 c  and  6   d  are respectively exploded prespective and cross-sectional views depicting the contaminant plug of a third preferred embodiment engaging a selected port of the medical instrument sterilization container of FIG.  1 . 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Preferred embodiments of the present invention are best understood by referring to FIGS. 1-6 of the drawings, like numerals being used for like and corresponding parts of the various drawings. 
     Referring first to FIG. 1, a medical instrument sterilization container is shown generally at  10 , and includes the housing  12  and a removable lid  14 . Lid  14  is preferably domed-shaped as shown in FIG. 1; however, lid  14  may also have other configurations as known in the art, such as being substantially flat. Removable tray  16  is received within the housing  12  and is adapted to receive various medical instruments, such as knives, scissors and the like. 
     An inlet port  18  is disposed through lid  14  in order to allow the passage of sterilizing steam and gases therethrough, while inhibiting or preventing the passage of dirt, dust, bacteria and other contaminants into the interior of the container. Two outlet ports, to be discussed below, are disposed in the bottom of housing  12 . Metal clamps  20  are attached to both sides of the housing  12  and are manually movable to clamp against the side of the lid  14  in order to lock lid  14  to the housing  12 . Suitable sealing surfaces are provided between the housing  12  and the lid  14  providing an essentially sealed container when the lid  14  is clamped to housing  12 . 
     FIG. 2 is a partially sectioned view of container  10 , which depicts outlet ports  22  and  24  extending from the bottom  25  of housing  12 . Ports  18 ,  22  and  24  each include a circular base plate  26  having a plurality of apertures  28  which communicate with the surrounding atmosphere. In inlet port  18 , base plate  26  is an integral part of domed shaped lid  14 . Annular sidewalls  30  form a receptacle which is adapted to receive a removable filter  32 . Removable filter  32  is held tightly within annular sidewalls  30  by a twistable cover  34  which engages a plurality of locking members  36  disposed around the periphery of the respective port. 
     Referring next to FIG. 3, an exploded view is shown which demonstrates the cooperation between a selected port  18 ,  22  or  24  with an associated filter  32  and twistable cover  34 . Twistable cover  34  includes four locking flanges  37  which extend from a lip member  38 . Locking flanges  37  are positioned to be rotated into locking members  36  formed around the periphery of the respective ports  18 ,  22  or  24 . A gripping member or handle  40  is provided on twistable cap  34  to facilitate its rotation within the respective annular sidewalls  30 . A typical filter is shown which is circular in shape and includes a plastic member having a lip  42 , plastic cross members  44  and a tab  46  extending from lip  42  to allow manual insertion or removal from the ports  18 ,  22  or  24 . 
     Referring next to FIGS. 4 a-b , which are top and side views of a first preferred embodiment, a contaminant plug  48  is designed to seal a selected port  18 ,  22  or  24 . Plug  48  includes a disk-shape cover plate  50  having an upper surface  52 , a lower surface  54  and a sidewall  56 . Contaminant plug  48  may be made of plastic, metal or any other suitable material. An annular flange  58  extends beyond the periphery of sidewall  56  and includes four locking flanges  60  which are positioned to engage locking members  36  disposed around a selected port  18 ,  22  or  24 . A slot  62  is formed in sidewall  56  around the periphery of cover plate  50 . An O-ring seal  64 , formed of silicone or another suitable compressible material which is contaminant impermeable, is disposed in slot  62 . A gripping member  66  is fastened to cover plate  50  by a screw  68 . 
     FIGS. 4 c  and  4   d  illustrate in detail the engagement of contaminant plug  48  with a selected one of ports  18 ,  22  or  24 . While in the preferred embodiment contaminant plug  48  is shown to be removable, it should be understood by persons skilled in the art that removability is not an essential requirement. FIG. 4 c  is an exploded perspective view of plug  48  and the selected port prior to engagement. FIG. 4 d  is a cross-sectional view showing contaminant plug  48  inserted into the selected port  18 ,  22  or  24  and engaged. Contaminant plug  48  is inserted into the selected port such that O-ring seal  64  is pressed firmly against annular sidewalls of ports  18 ,  22  and  24 . Using gripping member  66 , contaminant plug  48  can be twisted within sidewalls  30  such that locking flanges  60  engage locking members  36 . Locking flanges  60  are tightly held by locking members  36  such that O-ring seal  64  prevents the passage of contaminants from the interior of housing  12  through apertures  28  of the selected ports  18 ,  22 , or  24 . 
     Contaminant plug  48  may be used by medical personnel in place of filter  32  and twistable cover  34 , thus allowing medical instrument sterilization container  10  to be used as a receptacle for soaking instruments following surgery or for transporting medical instruments without cross contamination with the outside environment. When desired, plugs  48  may be removed or opened, thus allowing the container  10  again to be used in connection with the sterilization of medical instruments. 
     FIGS. 5 a  and  5   b  illustrate top and side views of a second embodiment of the present invention. A contaminant plug is shown generally at  70 , and includes a twistable cover  34  and a disk-shaped compression seal  72  comprised of silicone or another suitable compressible material. Compression seal  72  is shown as a discrete member inserted directly into a selected port  18 ,  22  or  24 ; however, compression seal  72  may be directly fastened to twistable cover  34  to provide a single unit. In either case, compression seal  72  is pressed tightly against the base  26  of the selected port  18 ,  22  or  24 , thereby sealing off perforations  28 . The engagement of compression seal  72  and twistable cover  34  is depicted in FIG. 5 c  which is an exploded perspective view of contaminant plug  70  and a selected port  18 ,  22  or  24 , and FIG. 5 d  which is a cross-sectional view showing compression seal  72  and cover  34  engaged in the selected port. Contaminant plug  70  has the significant advantage of utilizing the twistable cover  34  already available for retaining filters  32 . Further, compression seal  72  may be disposable for convenience. 
     Turn next to FIGS. 6 a  and  6   b , wherein respective side and top views of a sealing disk  74  are shown for use in a third embodiment contaminant plug. Sealing disk  74  includes a circular base plate  76 , an annular sidewall  78  formed at an angle to base plate  76 , and a lip member  80  disposed around the edge of annular sidewall  78 . Preferably, a tab  82  is fastened to annular sidewall  78  to aid in the insertion and removal of sealing disk  74  from a selected port  18 ,  22  or  24 . Sealing disk  74  may be formed of a plastic or other suitable material that prevents passage of contaminants whether solid, liquid or gaseous. 
     FIGS. 6 c  and  6   d  are respective exploded perspective and cross-sectional views showing the engagement of disk  74  and twistable cover  34  in a selected port  18 ,  22 , or  24 . Sealing disk  74  is adapted to be inserted within sidewalls  30  of the selected port. Lip member  80  can seat on the bottom of housing  12  around the immediate periphery of the selected port  18 ,  22  or  24 . A twistable cover  34  then seats within the annular sidewall  78  of sealing disk  74 . When twistable cover  34  is twisted such that its locking flanges  37  engage with locking members  36  of the selected port  18 ,  22  or  24 , sealing disk  74  is firmly retained providing the requisite seal. This can be most easily seen by referring to FIG. 6 c , which is a perspective view showing a sealing disk  74  and an associated twistable cap  34  inserted and engaged in a selected port  18 ,  22  or  24 . Sealing disk  74 , when properly engaged with the selected port  18 ,  22  or  24 , thereby prevents the communication of contaminants between the interior and exterior of medical instrument sterilization container  10 . 
     Thus, the present invention enables a medical instrument sterilization container having inlet and outlet ports to be sealed to prevent the undesired escape of contaminants into the surrounding area. The present invention allows such a medical instrument sterilization container to be used for the safe transport of contaminated medical instruments without the risk of exposing the outside environment. Further, the present invention allows a medical instrument sterilization container to be used as a convenient receptacle for soaking medical instruments following such medical procedures as surgery. 
     While preferred embodiments of the invention and their advantages have been set forth in the above-detailed description, the invention is not limited thereto, but only by the scope and spirit of the appended claims.