Patent Publication Number: US-2022234303-A1

Title: Sterile Connection Of Tubing

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of and priority of U.S. Provisional Patent Application Ser. No. 63/140,995, filed Jan. 25, 2021, the contents of which are incorporated by reference herein. 
    
    
     BACKGROUND 
     Field of the Disclosure 
     The invention relates to joinder of tubing. More particularly, the invention relates to systems and methods for sterilely joining tubing. 
     Description of Related Art 
     Fluid flow systems or assemblies that are pre-sterilized and/or pre-assembled are used in a wide variety of medical and non-medical applications. Medical applications may include, for example, administration of medical fluids to a patient for therapeutic and/or diagnostic purposes, blood and/or blood component or other cell collection or processing, dialysis, and other medical procedures. Non-medical applications for such systems or assemblies may include, for example, pharmaceutical manufacturing and cell processing. In the medical field in particular, such flow systems commonly employ one or more pre-filled containers or other sources of medical fluid or agent and an associated fluid flow circuit or system (sometimes called a tubing set) containing the necessary flow tubing, valves, flow controllers, process chambers, and the like to carry out the particular procedure, either alone or in cooperation with a reusable controller or other device. It is not unusual, for example, for a medical fluid flow system to include or be used in association with a container of a suitable drug, saline, anticoagulant, dextrose solution, sterile water, cell preservative, or the like, to name just a few examples. 
     Such a fluid flow system can, however, pose manufacturing or assembly challenges for different reasons. One reason can be that the pre-filled containers of medical liquid, powder, or other agent that is administered to the patient or otherwise employed in the medical fluid flow system, require different sterilization techniques than other portions of the fluid flow system. For example, empty plastic tubing, containers, flow control devices, and/or processing devices or chambers, which do not contain any substantial amount of liquid or other agent, may be sterilized with gamma or electron beam (e-beam) radiation or by exposure to a sterilizing gas, e.g., ethylene oxide. However, gas sterilization would be ineffective to sterilize an agent, such as a liquid, powder, or drug, contained in a sealed container, and exposing the agent to ionizing radiation may degrade or otherwise have a deleterious effect on the agent. Also, there may be situations where different portions of a sterile fluid flow system, even though suitable for the same sterilization process, are separately manufactured and sterilized for other reasons and then subsequently assembled in a sterile manner. 
     In addition, sterile connections often need to be made on-site, by the end user, e.g., at the location where the fluid flow systems are being used to treat patients or collect or process blood or blood components or biologic materials, or in other therapeutic or diagnostic procedures. As a result, a number of different approaches have been used in assembling sterile fluid flow systems. For example, one technique for manufacturing such systems employs the use of a sterile docking system, such as a device disclosed in U.S. Pat. No. 4,157,723, which is hereby incorporated herein by reference. As illustrated therein, the sterile docking system comprises a pair of mating members, each having a facing membrane. One of the mating members is connected to a pre-sterilized container of liquid, drug or other agent and the other mating member is attached to a pre-sterilized fluid flow system, which may include one or more empty containers. After the two members are joined, the docking system is exposed to radiant energy, causing the membranes to melt and form a sterile fluid pathway through the mating members. Fluid may then be transferred from the initial container into an empty container in the fluid flow system, and the flow path sealed and severed. The initial container and mating members are then discarded. While this works satisfactorily, it entails multiple manufacturing steps of transferring solution from one container to another in a sterile manner and the associated quality control procedures with such a step. It also requires the disposal of a portion of the product with increased product and waste cost. 
     According to an alternative approach, which is described in U.S. Pat. No. 4,978,446 (which is hereby incorporated herein by reference), sterilizing filters are used on the inlet flow line that couples a pre-sterilized liquid container or the like to a separately sterilized fluid flow tubing system. In this approach, medical personnel are required to manually join the fluid flow tubing system to the fluid container, such as by spiking the fluid container with a piercing member associated with the fluid flow system. In addition to the administrative requirements for individually ordering, storing, and prescribing solutions and disposable flow systems or sets, there is the added possibility of errors, such as by connection of a container of an incorrect liquid or other agent or an improper flow system to be used in association with the procedure. 
     Also, there are known devices commonly referred to as a sterile tubing welder, with the device marketed by Terumo Medical Corporation as the TSCA-II sterile tubing welder being one example. That device uses a heated cutting element to slice and melt the ends of tubing, which are joined together after the cutting element is removed. Aspects of this device are disclosed in U.S. Patent Application Publication No. 2020/0047423, which is hereby incorporated herein by reference. One notable disadvantage of this device is that it requires the use of expensive cutting elements (each comprising a resistive circuit layer sandwiched between two copper layers) that are replaced after each splice. 
     Accordingly, there remains a need for advancements in this field. 
     SUMMARY 
     There are several aspects of the present subject matter which may be embodied separately or together in the devices and systems described and claimed below. These aspects may be employed alone or in combination with other aspects of the subject matter described herein, and the description of these aspects together is not intended to preclude the use of these aspects separately or the claiming of such aspects separately or in different combinations as set forth in the claims appended hereto. 
     In one aspect, a sterile connection device includes a housing and first and second carriages. The first carriage includes a lower jaw defining a first portion of a proximal slot configured to receive a portion of a proximal sealed tube and defining a first portion of a distal slot configured to receive a portion of a distal sealed tube. The first carriage also includes an upper jaw configured to move between an open condition spaced away from the lower jaw and a closed condition positioned adjacent to the lower jaw. The second carriage is positioned laterally of the first carriage and includes a lower jaw defining a second portion of the proximal slot and a second portion of the distal slot, with an upper jaw that is configured to move between an open condition spaced away from the lower jaw and a closed condition positioned adjacent to the lower jaw. The sterile connection device further includes a blade handling assembly, a blade heating assembly, and a system controller. The system controller is configured to execute a sterile connection procedure when proximal and distal tubes are received by the proximal and distal slots and the upper jaws are in their closed conditions. The procedure includes controlling the blade heating assembly to heat the solid cutting blade by conductive heating, controlling the blade handling assembly to move the heated blade to a cutting position so as to cut the proximal and distal tubes, and controlling the second carriage to move proximally or distally with respect to the first carriage so as to align one of the portions of the proximal slot with one of the portions of the distal slot. The system controller then controls the blade handling assembly to advance the heated blade out of the cutting position, followed by controlling the first carriage to move laterally toward the second carriage so as to press cut ends of the proximal and distal tubes received by the aligned portions of the proximal and distal slots into contact with each other so as to sterilely connect the cut ends and define a joined tube. 
     In another aspect, a sterile connection device includes a housing and first and second carriages. The first carriage includes a lower jaw defining a first portion of a proximal slot configured to receive a portion of a proximal sealed tube and defining a first portion of a distal slot configured to receive a portion of a distal sealed tube. The first carriage also includes an upper jaw configured to move between an open condition spaced away from the lower jaw and a closed condition positioned adjacent to the lower jaw. The second carriage is positioned laterally of the first carriage and includes a lower jaw defining a second portion of the proximal slot and a second portion of the distal slot, with an upper jaw that is configured to move between an open condition spaced away from the lower jaw and a closed condition positioned adjacent to the lower jaw. The sterile connection device further includes a blade handling assembly, a blade heating assembly, and a system controller. The system controller is configured to execute a sterile connection procedure when proximal and distal tubes are received by the proximal and distal slots and the upper jaws are in their closed conditions. The procedure includes controlling the blade heating assembly to heat the solid cutting blade using a ceramic heating element, controlling the blade handling assembly to move the heated blade to a cutting position so as to cut the proximal and distal tubes, and controlling the second carriage to move proximally or distally with respect to the first carriage so as to align one of the portions of the proximal slot with one of the portions of the distal slot. The system controller then controls the blade handling assembly to advance the heated blade out of the cutting position, followed by controlling the first carriage to move laterally toward the second carriage so as to press cut ends of the proximal and distal tubes received by the aligned portions of the proximal and distal slots into contact with each other so as to sterilely connect the cut ends and define a joined tube. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of a sterile connection device according to an aspect of the present disclosure, with upper jaws of the device in a closed condition; 
         FIGS. 2 and 3  are perspective views of the sterile connect device of  FIG. 1 , with upper jaws of the device in an open condition; 
         FIGS. 4-6  are perspective views of the sterile connect device of  FIG. 1 , with various portions thereof broken away or omitted for illustrative purposes; 
         FIG. 7  is a top plan view of a disposable blade used in combination with the sterile connect device of  FIG. 1 ; 
         FIG. 8  is a side elevational view of a blade cartridge configured for dispensing blades of the type shown in  FIG. 7 ; 
         FIG. 9  is a perspective view of the blade cartridge of  FIG. 8 ; 
         FIG. 10  is a perspective view of another exemplary embodiment of a sterile connection device according to the present disclosure, with first and second carriages of the device aligned and upper jaws of the carriages in an open condition; 
         FIG. 11  is a perspective view of the sterile connection device of  FIG. 10 , with the upper jaws of the first and second carriages in a closed condition; 
         FIG. 12  is a perspective view of the sterile connection device of  FIG. 10 , with the first and second carriages out of alignment and the upper jaws in their closed condition; and 
         FIG. 13  is a perspective view of the sterile connection device of  FIG. 10 , with the first and second carriages out of alignment and the upper jaws in their open condition. 
     
    
    
     DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS 
     The embodiments disclosed herein are for the purpose of providing a description of the present subject matter, and it is understood that the subject matter may be embodied in various other forms and combinations not shown in detail. Therefore, specific designs and features disclosed herein are not to be interpreted as limiting the subject matter as defined in the accompanying claims. 
       FIGS. 1-3  illustrate an exemplary embodiment of a sterile connection device  10  according to an aspect of the present disclosure, while  FIGS. 4-6  illustrate the sterile connection device  10  with assorted portions thereof broken away or omitted for illustrative purposes. While sterile connection devices according to the present disclosure are particularly well-suited for sterile connection of tubes formed of polyvinyl chloride, it is within the scope of the present disclosure for the sterile connection device  10  to be used to sterilely connect tubes formed of other materials. 
     The illustrated sterile connection device  10  includes a housing  12  containing the various components of the sterile connection device  12 . The housing  12  may be variously configured without departing from the scope of the present disclosure, which may include the housing  12  having different portions being formed of, for example, a metallic material, a plastic material, or a combination of metallic and plastic materials. 
     In the illustrated embodiment, first and second carriages  14  and  16  are associated with an upper surface or face of the housing  12 , with the second carriage  16  being positioned laterally of the first carriage  14 . At least a portion of at least one of (but more preferably both of) the carriages  14 ,  16  is movable with respect to the housing  12  during a sterile connection procedure in which two sealed tubes “P” and “D” ( FIG. 4 ) are joined together. The first carriage  14  includes an upper jaw  18  and a lower jaw  20 , with the upper jaw  18  being movable between a closed condition ( FIG. 1 ) and an open condition ( FIGS. 2-4 ). The upper jaw  18  of the illustrated embodiment is pivotal between the closed and open conditions, but it should be understood that the upper jaw  18  may be otherwise movable between the closed and open conditions (e.g., via vertical translational movement) without departing from the scope of the present disclosure. 
     When the upper jaw  18  is in the open condition, the lower jaw  20  is exposed or uncovered, which allows a pair of sealed tubes P and D to be mounted within the first carriage  14  (at the beginning of a sterile connection procedure) and allows for a joined tube “J” ( FIGS. 3 and 6 ) to be removed from the first carriage  14  (at the end of a sterile connection procedure). The lower jaw  20  of the first carriage  14  defines a first portion  22   a  of a proximal slot  24  and a first portion  26   a  of a distal slot  28  that is parallel to the first portion  22   a  of the proximal slot  24  ( FIG. 2 ). In the illustrated embodiment, the first portions  22   a  and  26   a  of the proximal and distal slots  24  and  28  are substantially identical, but it should be understood that they may be differently configured without departing from the scope of the present disclosure. Regardless of their exact configuration, each of the first portions  22   a ,  26   a  is sized and configured to accommodate a portion of a tube that is to be joined to the tube received by the other slot  24 ,  28 . This may include each first portion  22   a ,  26   a  having a general arcuate or V-shaped profile to facilitate proper positioning (namely, centering) of a tube inserted into the slot  24 ,  28 . 
     When the upper jaw  18  of the first carriage  14  is in its closed condition ( FIG. 1 ), it covers or overlays tubes received within the slots  24  and  28  to retain the tubes in position during a sterile connection procedure. The illustrated upper jaw  18  includes a latch  30  that is configured to engage a pin  32  of the lower jaw  20  when the upper jaw  18  is in the closed condition. Such an arrangement prevents inadvertent movement of the upper jaw  18  from the closed condition to the open condition (of  FIGS. 2-4 ), though it should be understood that other locking arrangements (e.g., a magnetic interlock) may be employed without departing from the scope of the present disclosure. 
     The second carriage  16  is similarly configured to the first carriage  14 , with an upper jaw  34  that may be configured in accordance with the foregoing description of the upper jaw  18  of the first carriage  14  and a lower jaw  36  that may be configured in accordance with the foregoing description of the lower jaw  20  of the first carriage  14 . 
     As will be described in greater detail, the second carriage  16  is configured to move proximally and distally with respect to the first carriage  14  (and with respect to the housing  12 ), but in an initial or default position, the second carriage  16  is positioned with a second portion  22   b  of the proximal slot  24  (which is defined by the lower jaw  36  of the second carriage  16 ) aligned with the first portion  22   a  of the proximal slot  24  and a second portion  26   b  of the distal slot  28  (which is defined by the lower jaw  36  of the second carriage  16 ) aligned with the first portion  26   a  of the distal slot  28 . With the second carriage  16  in such an initial or default position (and the upper jaws  18  and  34  in their open conditions), a proximal tube P may be inserted into the proximal slot  24 , with the proximal tube P being partially received by the first portion  22   a  of the proximal slot  24  (defined by the lower jaw  20  of the first carriage  14 ) and partially received by the second portion  22   b  of the proximal slot  24  (defined by the lower jaw  36  of the second carriage  16 ). Similarly, a distal tube D may be inserted into the distal slot  28 , with the proximal tube P being partially received by the first portion  26   a  of the distal slot  28  (defined by the lower jaw  20  of the first carriage  14 ) and partially received by the second portion  26   b  of the distal slot  28  (defined by the lower jaw  36  of the second carriage  16 ). The proximal and distal tubes P and D are mounted to the sterile connection device  10  in opposing orientations, with a (typically sealed) end of one of the tubes P, D positioned closer to the first carriage  14  and a (typically sealed) end of the other one of the tubes P, D positioned closer to the second carriage  16 . To that end, the upper surface or face of the housing  12  may be provided with indicia  38   a  and  38   b , which indicate the positions and orientations into which the tubes P and D are to be placed at the beginning of a sterile connection procedure. 
     In addition to the carriages  14  and  16 , the sterile connection device  10  also includes a blade handling assembly  40  ( FIGS. 4-6 ) incorporated into the housing  12 . The blade handling assembly  40  may be differently configured without departing from the scope of the present disclosure, but in any case is configured to move a solid cutting blade  42  ( FIG. 7 ) into different positions within the housing  12  during the course of a sterile connection procedure. In the illustrated embodiment, the blade handling assembly  40  includes a first linear drive motor  44  ( FIGS. 4-6 ), which is configured to enable movement in proximal and distal directions. As will be described in greater detail, the first linear drive motor  44  is actuated to move a blade  42  into position to be heated, along with optionally moving the second carriage  16  in proximal and distal directions. While a linear drive motor is illustrated, it should be understood that other mechanisms may be provided to effect proximal and distal movement of one or more components of the sterile connection device  10  (including a blade  42 ) relative to the housing  12 . 
     The illustrated blade handling assembly  40  includes a second linear drive motor  46  ( FIG. 6 ), which is configured to enable movement in upward and downward directions within the housing  12  during the course of a sterile connection procedure. As will be described in greater detail, the second linear drive motor  46  is actuated to move the blade  42  (after is has been heated) vertically into and out of a cutting position. While a linear drive motor is illustrated, it should be understood that other mechanisms may be provided to effect vertical movement of one or more components of the sterile connection device  12  (including a blade  42 ) relative to the housing  10 . 
     Regardless of the particular configuration of the blade handling assembly  40 , it is configured to move a blade from a dispensing position within the housing  12  to an intermediate position (where the blade is heated) and then to a cutting position (to cut the two tubes P and D received within the proximal and distal slots  24  and  28 ). The blade handling assembly  40  may move a blade into additional positions (e.g., a disposal position, which will be described herein) without departing from the scope of the present disclosure. 
     In the illustrated embodiment, the dispensing position coincides with the position from which a blade  42  is dispensed from of a blade cartridge  48  ( FIGS. 8 and 9 ). While the sterile connection device  10  is configured as a durable, reusable item, the blades  42  (and, typically the blade cartridge  48 ) are configured as single-use, disposable items. The illustrated blades  42  are configured as flat or planar wafers formed of a single material or blend of materials (e.g., solid metal, such as copper), in contrast to the multi-layer cutting elements of other sterile connection devices. The blade  42  of  FIG. 7  is shown as being substantially rectangular, but it should be understood that the shape of the blade  42  may vary without departing from the scope of the present disclosure. It will be appreciated that, on account of the blade  42  being provided as a disposable, single-use item, it is advantageous for it have a simple and inexpensive configuration, rather than a more complicated and expensive configuration. 
     The illustrated housing  12  defines a slot or cavity configured to at least partially receive a blade cartridge  48 . One end  50  of the blade cartridge  48  includes an opening from which the blades  42  are individually dispensed. As best shown in  FIG. 5 , the open end  50  of the blade cartridge  48  is oriented adjacent to the first linear drive motor  44  of the blade handling assembly  40 . The first linear drive motor  44  is driven in a first or forward direction to move a pusher  52  in a proximal direction so as to contact a blade  42  positioned at the open end  50  of the blade cartridge  48  and move the blade  42  proximally and directly to an intermediate position between and beneath the first and second carriages  14  and  16 . The illustrated blade cartridge  48  is spring-loaded, such that dispensing one blade  42  from the open end  50  will cause one or more springs disposed within the blade cartridge  48  to press a subsequent blade  42  into position at the open end  50 , where it is ready to be dispensed for a subsequent sterile connection procedure. Once the blade cartridge  48  has been emptied (which may be determined by a sensor of the sterile connection device  10 , for example), it may be removed and replaced with a fully loaded blade cartridge  48 . Alternatively, the blade cartridge  48  may be removed, refilled with blades  42 , and then mounted back into the housing  12 . 
     In the intermediate position, the solid cutting blade  42  is heated by a blade heating assembly  54  incorporated into the housing  12 . The illustrated blade heating assembly  54  includes a heating element  56  and a thermocouple  58  (which are both shown in  FIG. 5 ), along with a temperature controller  60  ( FIG. 4 ). The heating element  56  may be variously configured without departing from the scope of the present disclosure, but in any case is configured to at least partially receive and/or support the solid cutting blade  42  in the intermediate position. The heating element  56  applies heat to the blade  42  prior to the blade  42  (and, optionally, the heating element  56  as well) being moved from the intermediate position to the cutting position (e.g., in an upward direction by the second linear drive motor  46 ), In an exemplary embodiment, the heating element  56  is configured as a ceramic heater having one or more plates that each contact or are positioned directly adjacent to at least a portion of the blade  42  to heat at least a portion of the blade  42  by conductive heating (as opposed to resistive heating, which is employed when a cutting element includes a resistive circuit layer), In the illustrated embodiment, the upper edge of the blade  42  is brought into contact with the tubes P and Ira to cut the tubes P and D, such that it is advantageous for the heating element  56  to be configured to apply heat to at least part of the upper edge of the blade  42 . However, as will be described in greater detail, the cut end of one of the tubes P, is moved along the adjacent face of the blade  42  prior to joining the cut ends, so it may be advantageous for a larger portion of the blade  42  (which may include substantially the entire blade  42 ) to be heated. 
     The manner in which the heating element  56  is itself heated depends upon the particular configuration of the blade heating assembly  54 . For example, in the exemplary embodiment in which the heating element  56  is configured as a ceramic heater, the one or more ceramic plates of the heating element  56  are heated by application of electricity to the plate(s) by the temperature controller  60 . The temperature controller  60  may be variously configured without departing from the scope of the present disclosure, with the temperature controller  60  being of the type marketed as the E5DC temperature controller by Omron Corporation of Kyoto, Japan in an exemplary embodiment. 
     The illustrated heating element  56  includes an internal thermocouple  58  that is electrically coupled to the temperature controller  60 . The thermocouple  58  produces a voltage that is dependent upon its temperature (which is dependent upon the temperature of the associated heating element  56 ), with the voltage being delivered to the temperature controller  60 . Upon the temperature controller  60  receiving a voltage that is indicative of a target temperature (which is approximately 300° C. in an exemplary embodiment), the temperature controller  60  transmits a signal to a system controller  62  ( FIGS. 4 and 6 ). The system controller  62  uses the signal from the temperature controller  60  to determine when the blade  42  has been sufficiently heated. This may include the system controller  62  determining that the blade  42  has been sufficiently heated upon receiving the signal from the temperature controller  60  or the system controller  62  making that determination at some later time (e.g., after a predetermined amount of time). Notably, in this embodiment, the temperature of the blade  42  itself is not monitored, but rather only the temperature of the heating element  56 . In other embodiments, the temperature of the blade  42  itself may be monitored, though monitoring only the temperature of the heating element  56  may be sufficient to determine the temperature of the blade  42 , particularly when a simple blade (e.g., a solid copper blade) is employed, on account of the blade  42  being heated to a predictable temperature upon application of a particular level of heat for a particular amount of time. 
     As for the system controller  62 , it may be variously configured without departing from the scope of the present disclosure, provided that it is configured to coordinate the various tasks carried out by the components of the sterile connection device  10  during a sterile connection procedure. In one embodiment, the system controller  62  may include a microprocessor (which, in fact may include multiple physical and/or virtual processors). According to other embodiments, the system controller  62  may include one or more electrical circuits designed to carry out the actions described herein. In fact, the system controller  62  may include a microprocessor and other circuits or circuitry. In addition, the system controller  62  may include one or more memories. The instructions by which the microprocessor is programmed may be stored on the memory associated with the microprocessor, which memory/memories may include one or more tangible non-transitory computer readable memories, having computer executable instructions stored thereon, which when executed by the microprocessor, may cause the microprocessor to carry out one or more actions as described herein. 
     Turning now to an exemplary sterile connection procedure, with the upper jaws  18  and  34  in their open condition (as in  FIG. 2 ) an operator places two tubes P and D into the proximal and distal slots  24  and  28  defined by the lower jaws  20  and  36  of the carriages  14  and  16 . The (typically sealed) end of the proximal tube P is positioned adjacent to the first carriage  14 , while the (typically sealed) end of the distal tube D is positioned adjacent to the second carriage  16 , as shown in  FIG. 4 . Notably, the tubes P and D may have different outer and inner diameters (within an allowable range), rather than necessarily having the same outer and inner diameters. 
     With the tubes P and Din place, the operator moves the upper jaws  18  and  34  from their open condition to their closed condition ( FIG. 1 ). The upper jaws  18  and  34  may be independently movable between their open and closed conditions or may be configured to move together from the open condition to the closed condition and/or from the closed condition to the open condition. As described above, in their closed conditions, the upper jaws  18  and  34  cover the lower jaws  20  and  36  and secure the tubes P and D within the carriages  14  and  16 . 
     In the illustrated embodiment, a tubing clamp  64  is configured to contact and compress the tubes P and D at a position between the first and second portions of the proximal and distal slots  24  and  28  when the upper jaws  18  and  34  are in the closed condition. By compressing the tubes P and D, the tubing clamp  64  moves any liquid away from the site at which the tubing clamp  64  engages the tubes P and D. As will be described in greater detail, this site corresponds to the location at which the tubes P and D are cut by the heated blade  42 , such that the tubing clamp  64  serves to clear liquid from the location at which the tubes P and D are cut. By clearing liquid from this location, it becomes possible to connect and join two tubes when at least one of them contains a liquid. Thus, the inclusion of a tubing clamp  64  allows for a “dry-to-dry” connection (in which neither tube P, D contains a liquid), a “dry-to-wet” connection (in which one tube P, D contains a liquid), and a “wet-to-wet” connection (in which both tubes P and D contain a liquid). 
     The tubing clamp  64  may be variously configured without departing from the scope of the present disclosure. In one embodiment, the tubing clamp  64  is associated with one or both of the upper jaws  18  and  34 , such that movement of the associated upper jaw(s)  18 ,  34  between open and closed conditions will cause similar movement of the tubing clamp  64 . In such a configuration, moving the upper jaws  18  and  34  to their closed condition will move the tubing clamp  64  into contact with the tubes P and D. The tubing clamp  64  may be formed of a metallic material or some other generally rigid material (to ensure that the tubing clamp  64  will compress the tubes P and D when the tubing clamp  64  is moved into contact with the tubes P and D), with the tubing clamp  64  being spring-loaded to control the amount of force applied to the tubes P and D by the tubing clamp  64 . 
     With the upper jaws  18  and  34  in their closed condition, the operator presses a “start” button  66  to continue the sterile connection procedure. In one embodiment, a solid cutting blade  42  is already positioned at the intermediate position (received by the heating element  56  and ready to be heated) when the “start” button  66  is pressed. In this case, pressing the “start” button  66  causes the system controller  62  to command the blade heating assembly  54  to heat the blade  42  to a desired temperature (which may be estimated based on the temperature of the heating element  56  of the blade heating assembly  54 , as explained above). If a blade  42  is not present in the intermediate position (as determined by a sensor, for example), pressing the “start” button  66  causes the system controller  62  to command the blade handling assembly  40  to move a blade  42  from the blade cartridge  48  to the intermediate position (e.g., by action of the first linear drive motor  44 ), followed by the system controller  62  commanding the blade heating assembly  54  to heat the blade  42  to a target temperature. 
     Upon the blade  42  reaching the target temperature (e.g., as determined by the system controller  62 , based upon a signal received from the temperature controller  60 ), the heated blade  42  is moved from the intermediate position to the cutting position. In the illustrated embodiment, this movement is in the upward direction and carried out by actuation of the second linear drive motor  46  of the blade handling assembly  40 . The heated blade  42  presses against the tubes P and D, which are in turn pressed against the tubing clamp  64 . The tubing clamp  64  may remain in position while the heated blade  42  presses against the tubes P and D or may be moved by the heated blade  42  (and/or the heating element  56 , if the heating element  56  moves to the cutting position with the heated blade  42 ). In one embodiment, the tubing clamp  64  is moved from its lowered position (which corresponds to the closed condition of the upper jaws  18  and  34 ) to a raised position by the heated blade  42  and/or the heating element  56  as the blade  42  cuts the tubes P and D, with the tubing clamp  64  being locked into the raised position by a spring  68  moving a latching mechanism  70  into place, or the like. 
     When the blade  42  has cut through the tubes P and D, the second carriage  16  is moved distally with respect to the first carriage  14  and with respect to the blade  42  (which remains in its cutting position). This movement draws the cut end of the proximal tube P positioned within the second portion  22   b  of the proximal slot  24  along the heated blade  42 , into alignment with the cut end of the distal tube positioned within the first portion  26   a  of the distal slot  28  ( FIG. 5 ). The second carriage  16  may be moved by any suitable mechanism, with the second carriage  16  being moved in the distal direction by the first linear drive motor  44  as the first linear drive motor  44  moves distally into position to deliver a subsequent blade  42  to the heating element  56 , in an exemplary embodiment. A spring  72  ( FIG. 6 ) may also (or alternatively) be employed to cause this distal movement of the second carriage  16 . 
     With the cut ends of the tubes P and  0  so aligned, the system controller  62  commands the blade handling assembly  40  to move the blade  42  back to the intermediate position (e.g., by actuating the second linear drive motor  46  in reverse to lower the heated blade  42 ) and then commands the first carriage  14  to be moved laterally toward the second carriage  16  so as to bring the cut ends of the tubes P and D into contact with each other. This movement may be carried out by any suitable mechanism, such as (for example) a spring  74  ( FIG. 5 ) pressing the first carriage  16  toward the second carriage  16  or a third linear drive motor (not illustrated) moving the first carriage  14  toward the second carriage  16 . 
     The cut ends of the tubes P and D are pressed together for a predetermined amount of time to create a joint and cool, after which time the system controller  62  advances to the next stage of the procedure. In this stage, the operator is notified that the tubes P and Q have been sterilely connected to define a joined tube J ( FIGS. 3 and 6 ). This notification may be provided in the form of an audible alert (e.g., an alarm) and/or a visual alert (e.g., a flashing light or an icon shown on a screen), for example. At this time, the system controller  62  unlocks the upper jaws  18  and  34  (if they are locked into their closed condition), which allows the operator to move the upper jaws  18  and  34  back into their open condition and then remove the joined tube J from the lower jaws  20  and  36  of the carriages  14  and  16  (along with the cut-off ends of the tubes P and D, which may be discarded). If required, the operator may manipulate the joined tube to ensure that the joint is secure and open for fluid flow (e.g., by pinching the joint). 
     At the end of the procedure, the operator presses a “reset” button  76  to reset the sterile connection device  10 . Pressing the “reset” button  76  causes the blade handling assembly  40  to move a blade  42  from the blade cartridge  48  to the heating element  56  in the intermediate position, which presses the heated blade  42  that was used in the just-completed procedure out of the heating element  56  and into a disposal receptacle  78 . The disposal receptacle  78  may be differently configured without departing from the scope of the present disclosure, with the illustrated disposal receptacle  78  being configured as a drawer positioned at the front or proximal face of the housing  12  and including a door or access  80  that may be opened to allow spent blades  42  to be removed from the disposal receptacle  78 . 
     The system controller  62  also commands the first and second carriages  14  and  16  to return to their default or initial positions (namely, by moving the first carriage  14  laterally away from the second carriage  16 , while moving the second carriage  16  in a proximal direction). In one embodiment, the first linear drive motor  42  is responsible for simultaneously moving the second carriage  16  to its original position and moving a blade  42  from the blade cartridge  48  to the intermediate position, though it is within the scope of the present disclosure for different mechanisms to be employed. 
       FIGS. 10-13  illustrate another exemplary configuration of a sterile connection device  100  according to the present disclosure. The sterile connection device  100  is similarly configured to the sterile connection device  10 , except that it is configured to simultaneously join two pairs of sealed tubes, rather than joining only a single pair of sealed tubes. To allow for two pairs of tubes to be joined, the sterile connection device  100  has modified carriages  102  and  104 . Whereas the carriages  14  and  16  of sterile connection device  10  (when aligned, as in  FIG. 2 ) combine to define a pair of parallel slots  24  and  28 , lower jaws  106  and  108  of carriages  102  and  104  of sterile connection device  100  combine to define four pairs of parallel slots  110 ,  112 ,  114 , and  116 . The individual slots  110 ,  112 ,  114 , and  116  may be similarly configured to the previously described slots  24  and  28 , with the lower jaw  106  of the first carriage  102  forming a first portion of each slot and the lower jaw  108  of the second carriage  104  forming an aligned second portion of the corresponding slot. More particularly, the lower jaw  106  of the first carriage  102  defines a first portion  118   a  of first slot  110 , a first portion  120   a  of second slot  112 , a first portion  122   a  of third slot  114 , and a first portion  124   a  of fourth slot  116 , while the lower jaw  108  of the second carriage  104  defines a second portion  118   b  of the first slot  110 , a second portion  120   b  of the second slot  112 , a second portion  122   b  of the third slot  114 , and a second portion  124   b  of the fourth slot  116 . 
     As shown in  FIG. 10 , a first tube “A” may be inserted into the first slot  110 , with the first tube A being partially received by the first portion  118   a  of the first slot  110  (defined by the lower jaw  106  of the first carriage  102 ) and partially received by the second portion  118   b  of the first slot  110  (defined by the lower jaw  108  of the second carriage  104 ). Similarly, a second tube “B” may be inserted into the second slot  112 , with a third tube “E” inserted into the third slot  114  and a fourth tube “F” inserted into the fourth slot  116 . The first and second tubes A and B (which are to be joined together) are mounted to the sterile connection device  100  in opposing orientations, with a (typically sealed) end of one of the tubes A, B positioned closer to the first carriage  102  and a (typically sealed) end of the other one of the tubes A, B positioned closer to the second carriage  104 . The third and fourth tubes E and F (which are to be joined together) are similarly mounted to the sterile connection device  100  in opposing orientations, as can be seen in  FIG. 10 . 
     With the tubes in place, the operator moves the respective upper jaws  126  and  128  of the first and second carriages  102  and  104  from their open condition ( FIG. 10 ) to their closed condition ( FIG. 11 ) to secure the tubes within the carriages  102  and  104 . If provided (as in the illustrated embodiment), a tubing clamp  130  contacts and compresses the tubes at a position between the first and second portions of each slot when the upper jaws  126  and  128  are in the closed condition to move any liquid away from the location at which the tubes are to be cut. 
     With the upper jaws  126  and  128  in their closed condition, the operator presses a “start” button  132  to continue the sterile connection procedure. In one embodiment, a solid cutting blade is already positioned at an intermediate position (received by a heating element and ready to be heated) when the “start” button  132  is pressed. In this case, pressing the “start” button  132  causes the system controller to command a blade heating assembly to heat the blade to a desired temperature. If a blade is not present in the intermediate position (as determined by a sensor, for example), pressing the “start” button  132  causes the system controller to command a blade handling assembly to move a blade from the blade cartridge  134  to the intermediate position, followed by the system controller commanding the blade heating assembly to heat the blade to a target temperature. As the blade is required to cut through four tubes instead of two (as in the embodiment of  FIGS. 1-6 ), each blade employed by the sterile connection device  100  may be elongated compared to the blades  42  employed by the sterile connection device  10 . Alternatively, rather than providing one elongated blade, it is also within the scope of the present disclosure for a plurality of blades (which may be similarly or differently configured) to be used when cutting the four tubes. 
     Upon the blade reaching the target temperature, the heated blade is moved from the intermediate position to the cutting position by the blade handling assembly. The heated blade presses against the tubes, which are in turn pressed against the tubing clamp  130  to cut through the tubes. When the blade has cut through the tubes, the second carriage  104  is moved distally with respect to the first carriage  102  and with respect to the blade (which remains in its cutting position). This movement draws the cut ends of the first tube A and the third tube E along the heated blade, into alignment with the cut ends of the second tube B and the fourth tube F, respectively ( FIG. 12 ). 
     With the cut ends of the tubes so aligned, the system controller commands the blade handling assembly to move the blade back to the intermediate position and then commands the first carriage  102  to be moved laterally toward the second carriage  104  so as to bring the aligned cut ends of the two pairs of tubes into contact with each other. The cut ends of the first and second tubes A and B and of the third and fourth tubes E and F are pressed together for a predetermined amount of time to create a joint and cool, after which the system controller advances to the next stage of the procedure. 
     In the next stage, the operator is notified that the first and second tubes A and B have been sterilely connected to define a first joined tube “C,” with the third and fourth tube E and F being sterilely connected to define a second joined tube “G.” At this time, the system controller unlocks the upper jaws  126  and  128  (if they are locked into their closed condition), which allows the operator to move the upper jaws  126  and  128  back into their open condition ( FIG. 13 ) and then remove the joined tubes C and G from the lower jaws  106  and  108  of the carriages  102  and  104  (along with the cut-off ends of the tubes, which may be discarded). If required, the operator may manipulate the joined tubes to ensure that the joints are secure and open for fluid flow (e.g., by pinching the joint). At the end of the procedure, the operator presses a “reset” button  136  to reset the sterile connection device  100 . 
     While it will be seen that the sterile connection device  100  of  FIGS. 10-13  is particularly suited for simultaneously joining two pairs of tubes, it should be understood that the sterile connection device  100  may also be used to join a single pair of tubes. Additionally, while the sterile connection device  100  is shown as being configured to join one or two pairs of tubes, it should be understood that a sterile connection device may be configured to simultaneously join three or more pairs of tubes by providing suitably configured components (e.g., elongated carriages and blades). 
     It should again be emphasized that the illustrated sterile connection devices  10  and  100  are merely exemplary and that sterile connection devices according to the present disclosure may be differently configured without departing from the scope of the present disclosure. This may include a sterile connection device having its components differently arranged and/or a sterile connection device including additional components (e.g., a cord for connection to an external power source, a variety of sensors, and/or a touchscreen for use by an operator). 
     Aspects 
     Aspect 1. A sterile connection device comprising: a housing; a first carriage including a first lower jaw defining a first portion of a proximal slot configured to receive a portion of a proximal sealed tube and defining a first portion of a distal slot configured to receive a portion of a distal sealed tube, and a first upper jaw configured to move between an open condition spaced away from the first lower jaw and a closed condition positioned adjacent to the first lower jaw; a second carriage positioned laterally of the first carriage and including a second lower jaw defining a second portion of the proximal slot and a second portion of the distal slot, and a second upper jaw configured to move between an open condition spaced away from the second lower jaw and a closed condition positioned adjacent to the second lower jaw; a blade handling assembly configured to move a solid cutting blade into a plurality of positions within the housing; a blade heating assembly; and a system controller configured to execute a sterile connection procedure when proximal and distal tubes are received by the proximal and distal slots and the first and second upper jaws are in the closed conditions, wherein the sterile connection procedure includes controlling the blade heating assembly to heat the solid cutting blade, controlling the blade handling assembly to move the heated blade to a cutting position so as to cut the proximal and distal tubes, controlling the second carriage to move proximally or distally with respect to the first carriage so as to align one of the portions of the proximal slot with one of the portions of the distal slot, controlling the blade handling assembly to advance the heated blade out of the cutting position, and controlling the first carriage to move laterally toward the second carriage so as to press cut ends of the proximal and distal tubes received by the aligned portions of the proximal and distal slots into contact with each other so as to sterilely connect the cut ends and define a joined tube, wherein the solid cutting blade is heated by conductive heating applied by the blade heating assembly. 
     Aspect 2. The sterile connection device of Aspect 1, wherein the blade heating assembly comprises a ceramic heating element. 
     Aspect 3. The sterile connection device of any one of the preceding Aspects, wherein the blade heating assembly includes an internal thermocouple configured to measure a temperature of a portion of the blade heating assembly and not a temperature of the solid cutting blade. 
     Aspect 4. The sterile connection device of Aspect 3, wherein the blade heating assembly includes a temperature controller associated with the internal thermocouple and configured to transmit a signal to the system controller upon determining that the said portion of the blade heating assembly has reached a target temperature, and the system controller is configured to control the blade handling assembly to move the heated blade to the cutting position so as to cut the proximal and distal tubes based at least in part on the signal from the temperature controller. 
     Aspect 5. The sterile connection device of any one of the preceding Aspects, further comprising a tubing clamp configured to contact and compress the proximal and distal tubes at a position between the first and second portions of the proximal and distal slots when the upper jaws are in the closed conditions. 
     Aspect 6. The sterile connection device of Aspect 5, wherein the tubing clamp is configured to be contacted and moved by the heating blade from a lowered position to a raised position upon the heated blade being moved to the cutting position by the blade handling assembly. 
     Aspect 7. The sterile connection device of any one of the preceding Aspects, further comprising a “reset” button configured to be manipulated by an operator, wherein manipulation of the “reset” button instructs the controller to control the blade handling assembly to move the heated blade to a disposal receptacle. 
     Aspect 8. The sterile connection device of Aspect 7, wherein manipulation of the “reset” button instructs the controller to control the blade handling assembly to move a subsequent solid cutting blade from a blade cartridge directly to an intermediate position between the blade cartridge and the cutting position, with movement of the subsequent solid cutting blade to the intermediate position causing the heated blade to be moved to the disposal receptacle. 
     Aspect 9. The sterile connection device of any one of the preceding Aspects, wherein the blade handling assembly includes a first linear drive motor configured to advance the solid cutting blade from a blade cartridge directly to an intermediate position between the blade cartridge and the cutting position, with the solid cutting blade being heated by the blade heating assembly in the intermediate position, and a second linear drive motor configured to advance the heated blade from the intermediate position to the cutting position. 
     Aspect 10. The sterile connection device of Aspect 9, wherein the first linear drive motor is configured to move the solid cutting blade in a direction substantially perpendicular to a direction in which the second linear drive motor is configured to move the heated blade. 
     Aspect 11. The sterile connection device of any one of Aspects 9-10, wherein the first linear drive motor is configured to move from the intermediate position toward the blade cartridge so as to cause the second carriage to move proximally or distally with respect to the first carriage so as to align said one of the portions of the proximal slot with said one of the portions of the distal slot. 
     Aspect 12. The sterile connection device of any one of the preceding Aspects, further comprising a first spring configured to bias the first carriage toward the second carriage, wherein the system controller is configured to control the first carriage to move laterally toward the second carriage by allowing the spring to move the first carriage toward the second carriage. 
     Aspect 13. The sterile connection device of any one of the preceding Aspects, further comprising a second spring configured to bias the second carriage to move proximally or distally with respect to the first carriage, wherein the system controller is configured to control the second carriage to move proximally or distally with respect to the first carriage by allowing the second spring to move the second carriage proximally or distally with respect to the first carriage. 
     Aspect 14. The sterile connection device of any one of the preceding Aspects, configured to simultaneously join multiple pairs of tubes. 
     Aspect 15. The sterile connection device of any one of the preceding Aspects, wherein the solid cutting blade comprises a solid copper blade. 
     Aspect 16. A sterile connection device comprising: a housing; a first carriage including a first lower jaw defining a first portion of a proximal slot configured to receive a portion of a proximal sealed tube and defining a first portion of a distal slot configured to receive a portion of a distal sealed tube, and a first upper jaw configured to move between an open condition spaced away from the first lower jaw and a closed condition positioned adjacent to the first lower jaw; a second carriage positioned laterally of the first carriage and including a second lower jaw defining a second portion of the proximal slot and a second portion of the distal slot, and a second upper jaw configured to move between an open condition spaced away from the second lower jaw and a closed condition positioned adjacent to the second lower jaw; a blade handling assembly configured to move a solid cutting blade into a plurality of positions within the housing; a blade heating assembly; and a system controller configured to execute a sterile connection procedure when proximal and distal tubes are received by the proximal and distal slots and the first and second upper jaws are in the closed conditions, wherein the sterile connection procedure includes controlling the blade heating assembly to heat the solid cutting blade, controlling the blade handling assembly to move the heated blade to a cutting position so as to cut the proximal and distal tubes, controlling the second carriage to move proximally or distally with respect to the first carriage so as to align one of the portions of the proximal slot with one of the portions of the distal slot, controlling the blade handling assembly to advance the heated blade out of the cutting position, and controlling the first carriage to move laterally toward the second carriage so as to press cut ends of the proximal and distal tubes received by the aligned portions of the proximal and distal slots into contact with each other so as to sterilely connect the cut ends and define a joined tube, wherein the solid cutting blade is heated by a ceramic heating element of the blade heating assembly. 
     Aspect 17. The sterile connection device of Aspect 16, wherein the blade heating assembly includes an internal thermocouple configured to measure a temperature of a portion of the blade heating assembly and not a temperature of the solid cutting blade. 
     Aspect 18. The sterile connection device of Aspect 17, wherein the blade heating assembly includes a temperature controller associated with the internal thermocouple and configured to transmit a signal to the system controller upon determining that the said portion of the blade heating assembly has reached a target temperature, and the system controller is configured to control the blade handling assembly to move the heated blade to the cutting position so as to cut the proximal and distal tubes based at least in part on the signal from the temperature controller. 
     Aspect 19. The sterile connection device of any one of Aspects 16-18, further comprising a tubing clamp configured to contact and compress the proximal and distal tubes at a position between the first and second portions of the proximal and distal slots when the upper jaws are in the closed conditions. 
     Aspect 20. The sterile connection device of Aspect 19, wherein the tubing clamp is configured to be contacted and moved by the heating blade from a lowered position to a raised position upon the heated blade being moved to the cutting position by the blade handling assembly. 
     Aspect 21. The sterile connection device of any one of Aspects 16-20, further comprising a “reset” button configured to be manipulated by an operator, wherein manipulation of the “reset” button instructs the controller to control the blade handling assembly to move the heated blade to a disposal receptacle. 
     Aspect 22. The sterile connection device of Aspect 21, wherein manipulation of the “reset” button instructs the controller to control the blade handling assembly to move a subsequent solid cutting blade from a blade cartridge directly to an intermediate position between the blade cartridge and the cutting position, with movement of the subsequent solid cutting blade to the intermediate position causing the heated blade to be moved to the disposal receptacle. 
     Aspect 23. The sterile connection device of any one of Aspects 16-22, wherein the blade handling assembly includes a first linear drive motor configured to advance the solid cutting blade from a blade cartridge directly to an intermediate position between the blade cartridge and the cutting position, with the solid cutting blade being heated by the blade heating assembly in the intermediate position, and a second linear drive motor configured to advance the heated blade from the intermediate position to the cutting position. 
     Aspect 24. The sterile connection device of Aspect 23, wherein the first linear drive motor is configured to move the solid cutting blade in a direction substantially perpendicular to a direction in which the second linear drive motor is configured to move the heated blade. 
     Aspect 25. The sterile connection device of any one of Aspects 23-24, wherein the first linear drive motor is configured to move from the intermediate position toward the blade cartridge so as to cause the second carriage to move proximally or distally with respect to the first carriage so as to align said one of the portions of the proximal slot with said one of the portions of the distal slot. 
     Aspect 26. The sterile connection device of any one of Aspects 16-25, further comprising a first spring configured to bias the first carriage toward the second carriage, wherein the system controller is configured to control the first carriage to move laterally toward the second carriage by allowing the spring to move the first carriage toward the second carriage. 
     Aspect 27. The sterile connection device of any one of Aspects 16-26, further comprising a second spring configured to bias the second carriage to move proximally or distally with respect to the first carriage, wherein the system controller is configured to control the second carriage to move proximally or distally with respect to the first carriage by allowing the second spring to move the second carriage proximally or distally with respect to the first carriage. 
     Aspect 28. The sterile connection device of any one of Aspects 16-27, configured to simultaneously join multiple pairs of tubes. 
     Aspect 29. The sterile connection device of any one of Aspects 16-28, wherein the solid cutting blade comprises a solid copper blade. 
     It will be understood that the embodiments described above are illustrative of some of the applications of the principles of the present subject matter. Numerous modifications may be made by those skilled in the art without departing from the spirit and scope of the claimed subject matter, including those combinations of features that are individually disclosed or claimed herein. For these reasons, the scope hereof is not limited to the above description but is as set forth in the following claims, and it is understood that claims may be directed to the features hereof, including as combinations of features that are individually disclosed or claimed herein.