Abstract:
A method and apparatus for filling a syringe-type applicator having multiple material reservoirs are disclosed. The method and apparatus permits the individual component reservoirs to be simultaneously filled without risk of contamination or unintentional component mixing. The method and apparatus are particularly useful in the preparation and delivery of multiple component tissue sealants such a fibrinogen adhesive compositions.

Description:
REFERENCE TO RELATED APPLICATIONS 
     This application discloses subject matter related to our co-pending U.S. Continuation-In-Part patent application Ser. No. 09/456,728, filed Dec. 8, 1999, which claims priority from U.S. patent application Ser. No. 09/307,056 May 7, 1999, which claims priority from United States Provisional Application No. 60/087,856 filed Jun. 3, 1998, all naming Gordon H. Epstein as first inventor. The disclosures of the aforementioned United States patent applications, “the above applications” are hereby incorporated herein by reference thereto. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to a filling device for an syringe applicator which applies multiple fluid sealant components to a work surface and is particularly, although not exclusively, useful for applying tissue sealant components to biological tissue to effect hemostasis or achieve other therapeutic results. More particularly, it relates to a dual compartment enclosed direct filling device for a hand-held applicator. 
     BACKGROUND OF THE INVENTION 
     The use of tissue sealants and other biological materials is an important emerging surgical technique, well adapted for the operating room or field environments such as the doctor&#39;s office or mobile medical units. Preferred sealants include fibrin sealants which are formed from blood plasma components and comprise, on the one hand, a first component containing fibrinogen and Factor XIII and, on the other hand, a second component which usually includes thrombin, and calcium ions. The fibrinogen is capable of a polymerizing and being cross-linked to form a solid fibrin clot when the components are mixed. The necessary additional factors to simulate relevant portions of the natural blood coagulation cascade are suitably distributed between the fibrinogen and thrombin components. 
     Antanavich et al. U.S. Pat. No. 5,585,007, whose disclosure and references are hereby incorporated herein by reference thereto, provides an extensive discussion of the literature relating to fibrinogen sealant preparation (column 1, line 20 to column 4, line 62) and applicators (column 4 line 62 to column 5, line 14), as well as a bibliography, (columns 6-10) and is a helpful guide to the teachings of prior workers in the field. 
     Depending upon the potency of the particular formulations employed, coagulation of the sealant may take place very rapidly, yielding a gel within perhaps 10 or 20 seconds. Though often very desirable for surgical reasons, such fast-acting properties present potential problems of fouling or clogging. These problems must be overcome in devising suitable applicators, methods of application, and devices suitable for filling said applicators. 
     A popular manually operable applicator for such two-component sealants employs a dual syringe construction wherein two syringes, connected by a yoke, each provide a reservoir for one of the components. In most prior devices, the sealant components are discharged in separate streams and mixed external of the applicator. Such applicators are similar in principle to household epoxy glue applicators commonly available in hardware stores. 
     Until May of 1998, when the FDA first approved such products, fibrin sealants were not commercially available in the US. Therefore, the use of fibrin sealants was limited to supplies produced within the clinic, which were not subject to FDA control. 
     Current methods of filling biological glue applicators can be complicated and time consuming. As taught in U.S. Pat. No. 5,266,877, issued to Epstein, and in our assignee&#39;s international application PCT/US98/07846, components of the sealant can be placed in separate compartments in a flat filler tray for transfer to an applicator. Though useful as a device to permit rapid and reliable filling of a dual syringe applicator at the point of use, such filler trays are not suitable for external storage of the sealant components. This process can be time consuming and it requires a significant degree of care to efficiently transfer the sealant to the applicator. Also, a small amount of sealant will be left in the tray, and it is thus wasted. Furthermore the transfer of sealant components to multiple storage containers raises the likelihood members in which the sealants will gather bio-burden, and bacteria, which can threaten the sterility of the sealant. 
     Following FDA approval, however, fibrin sealants are now commercially available in the US. This availability has created a need for an effective and efficient device useful for transferring the components of the sealant, from commercially available or standardized, container-like storage containers, into an applicator. 
     There is accordingly a need for a device which can effectively deliver, in a sterile environment, multiple sealant components directly from their storage containers to a syringe applicator. 
     SUMMARY OF THE INVENTION 
     The present invention solves the problem of effectively delivering multiple sealant components directly from commercially available or standardized storage containers, for example, containers, to an applicator while allowing the use of the entire fill device within a sterile field. 
     In one aspect, the invention provides a direct dual filling device for multiple sealant components of a liquid sealant, at least two of the components being complementary one to the other and capable of polymerizing when mixed. The direct dual filling device comprises a body having a plurality of inlet ports connected to drawing tubes which pierce the protective covering of commercially available containers, the containers containing the sealant components. The device also includes a housing member which sealably mounts onto a base, thereby enclosing the containers within the structure and allowing the device to be brought into a sterile field. The housing member and slanted container supports hold the containers in a tilted position within the receiving aperture. This feature allows the drawing tubes to extract virtually all of the fluid contained within the containers. The device can be attached to a syringe applicator with keying such that when the plunger of the syringe applicator is retracted, fluid is drawn from each respective container to the proper reservoir contained within the syringe applicator. 
     The invention enables multiple sealant components to be directly delivered from their commercially available containers into a syringe applicator without significant risk of contamination of the sealant components, while minimizing waste of the sealant components. The different sealant components are delivered directly from their containers into separate individual reservoirs within the syringe applicator, thereby preventing coagulation of the sealant components. Once the housing member of the device is guided onto the containers and mounted onto the base, the entire device can be brought into the sterile environment. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The apparatus of the present invention will be explained in more detail by way of the accompanying drawings, wherein: 
     FIG. 1 show a side elevation view of the present invention attached to a syringe-type applicator; 
     FIG. 2 shows an alternate side view of the present invention attached to a syringe-type applicator; 
     FIG. 3 shows a cross-sectional view of the present invention attached to a syringe-type applicator; 
     FIG. 4 shows a top view of the container interface of the present invention having two containers disposed within the housing assembly; 
     FIG. 5 shows a cross-sectional view of the present invention having two containers disposed within the housing assembly and a syringe-type applicator attached to the device; 
     FIG. 6 shows an exploded view of the housing assembly of the present invention; and 
     FIG. 7 shows an exploded view of the container positioning members of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Disclosed herein is a detailed description of various illustrated embodiments of the invention. This description is not to be taken in a limiting sense, but is made merely for the purpose of illustrating the general principles of the invention. The section titles and overall organization of the present detailed description are for the purpose of convenience only and are not intended to limit the present invention. 
     The direct dual filling device of the present invention is used in conjunction with a syringe-type sealant applicator, to dispense a tissue sealant thereby effecting hemostasis or achieving other therapeutic results. The direct dual filling device of the present invention is designed to permit the withdrawal of fluid from at least one commercially available fluid container and fill a syringe-type applicator, for example, the DUPLOJECT™ syringe-type applicator manufactured by the Baxter Corporation. As those skilled in the art will appreciate, the present invention permits the controlled withdrawal of fluid from the fluid container and filling of at least one material reservoir of the syringe-type applicator. It is anticipated as being within the scope of the present invention to produce a direct dual filling device capable of functionally coupling with a plurality of syringe-type applicators in a plurality of sizes. 
     Referring to FIGS. 1 and 2 of the drawings, the direct dual filling device  10  comprises a body  12 , a housing member  14  and a collar  15  which is adapted to fit a syringe-type applicator  18 , and a separable base portion  16 . The inventive device is preferably constructed out of a clear thermoplastic material such as polycarbonate, polystyrene, polypropylene, polytetrafluoroethylene, acrylonitrile butadiene-styrene or acrylic, however any suitable material may be used. 
     Applicator  18  preferably has at least one fluid reservoir for holding and controllably dispensing reactable fluids, the fluid reservoir being connected to a syringe by a fluid conduit (not shown). As shown in FIG. 1, the illustrated embodiment of the applicator  18  has two fluid reservoirs  19   a  and  19   b  for holding and controllably dispensing reactable fluids, with each of the fluid reservoirs being connected to the syringe by fluid conduits (not shown). The applicator  18  is of the type primarily used for applying multiple fluid sealant components to biological tissue to effect hemostasis or achieve other therapeutic results. However the inventive filling device can be adapted to fit applicators having a wide variety of uses and having a plurality of fluid reservoirs which require the direct filling of fluids into separate reservoirs located within an applicator. 
     As shown in FIG. 3, housing member  14  comprises a first surface  20  defining a receiving aperture  22 , and a second surface  24  forming the exterior of housing member  14  which is integral to the collar  15 . The first surface  20  has a proximal portion  26  substantially parallel to the longitudinal axis  28  of the dual filling device  10 , a medial portion forming a biasing member  30 , and a distal portion forming an angular stop  32 . Collar  15  disposes inlet ports  34  and  36  which are adapted to receive the syringe-type applicator  18 . Rubber O-rings  38  and  40  are positioned within inlet ports  34  and  36  respectively, such that an air tight seal is formed. Inlet ports  34  and  36  are connected to drawing tubes  42  and  44  by transverse channels  46  and  48  respectively. 
     Drawing tubes  42  and  44  should have sufficient length to extract substantially all the liquid contained within a container (not shown) positioned within the receiving aperture  22 , or conversely they should have a length such that when the system is inverted substantially all of the liquid can be extracted. Drawing tubes  42  and  44  are preferably configured with pointed ends  50  and  52  which have the ability to pierce the protective packaging found on standard medical fluid containers (not shown) and form a seal. Drawing tubes  42  and  44  are preferably formed out of a metallic material, however any suitable material such as thermoplastic may be used. The tubes can also have the ability to be removed from traverse channels  46  and  48  for replacement. Both of the tubes,  42  and  44 , may be of similar diameter, however the tube diameter may differ to accommodate liquids having differing viscosities. 
     Channel  46  allows the fluid contained within an isolated container to be drawn through tube  42  and into the reservoir  19   a  located within applicator  18  without risk of contamination. Similarly, channel  48  allows the fluid contained within another isolated container to be drawn through tube  44  and deposited within reservoir  19   b  located within the applicator  18  without risk of contamination. This allows the simultaneous filling of both sides of the applicator directly from the commercially available containers. Channels  46  and  48  can be formed out of thermoplastic tubing or molded directly into body  12  of the direct filling device  10 . 
     As shown in FIG. 4, in order to fill applicator (not shown) directly from containers  54  and  56 , housing member (not shown) is placed over said containers  54  and  56  such that pointed tips  50  and  52  are approximately centered on the protective seals  53   a  and  53   b  covering the containers. The contoured shape of housing member  14  guides the inventive device as the containers are seated and snap into place within housing member  14  by locking members  58 . As shown in FIG. 4, locking members  58  are located within housing member  14  such that they move apart when the caps of the respective containers passes by during the insertion of the container, then once the container has reached the proper location locking members  58  retract under the container caps to lock or “seat” the containers in place. 
     The plunger of the syringe-type applicator  18  is then retracted thereby drawing the fluid contained within containers  54  and  56 , respectively, through their respective drawing tubes  42  and  44  and channels  46  and  48 , and into the syringes of applicator  18  for deposit within reservoirs  19   a  and  19   b.    
     As depicted in FIG. 5, containers  54  and  56  are inserted into housing member  14  until seated by locking members  58  (see FIG.  4 ). The shape of housing member  14  may be varied to allow use of different types and shapes of containers, or alternatively, may be tapered to permit the easy grasp of base  16  when attached to housing member  14 , thereby simplifying separation. The housing member  14  and the receiving aperture  22  can also be modified so that each side allows insertion of a different shaped container, thereby keying the containers to the fill device. This in conjunction with the novel shape of the collar is important in ensuring that the proper components are delivered to the proper reservoirs within the applicator. Housing member  14  can be contoured to resemble the shape of the filling device when assembled with agent containers. The shape can also vary to allow use of different types and shapes of containers. 
     A novel feature of the present invention is the tilted container feature permitting withdrawal of substantially all fluid from agent containers. The angled biasing member  30  forcibly tilts the containers  54  and  56  disposed within the receiving aperture  22 , thereby permitting withdrawal of substantially all fluids within the containers. The use of the angular stop member  32  permits an indexed tilting feature while controlling the penetration depth of drawing tubes  42  and  44 . In another embodiment housing member  14  may be constructed eliminating the angled biasing member  30  and angular stop  32 . The housing member can be modified so that each side allows insertion of a different shaped container, thereby keying the containers to the fill device. This, in conjunction with the novel shape of the collar  15 , helps ensure that the proper components are delivered to the proper reservoirs within the applicator. 
     As shown in FIGS. 6 and 7, the direct dual filling device  10  utilizes a housing member  14 , formed of a first housing member portion  14   a  and a second housing member portion  14   b , and base portion  16  to position containers within the receiving aperture  22  (see FIG.  3 ). Base  16  has base plate portion  62  and a vertical support member  64  disposing at least two angled container supports  66  and  68  to support containers  54  and  56  within the receiving aperture  22 . Angling supports  66  and  68  permits tilting of the containers resulting in withdrawal of substantially all the fluid from the container. As shown, the angled supports  66  and  68  may include a medial portion substantially parallel to base plate portion  62 , thereby aiding in preparing the device for use. Housing member  14  disposes a sealing base locking member  70  which sealably attaches the base plate portion  62  to the housing member  14 . The base locking member  70  may be comprised of retention devices including, without limitation, slip-fit mechanisms, snap-locking mechanisms and pin-locked mechanisms. 
     An additional embodiment of the present invention includes hinged drawing tube guides  80  and  82  comprising a forked distal portion  84  and  86 , respectively, and having the proximal portion attached to the first surface  20  by a hinge device. The hinged drawing tube guides,  80  and  82 , respectively, stabilize the drawing tube  42  and  44 , respectively, when containers are not placed within the receiving aperture  22 . When containers are inserted into the receiving aperture  22  the separate drawing tubes  42  and  44  enter the respective containers  54  and  56 , while hinged drawing tube guides  80  and  82  are folded into recesses  88  and  90  disposed on the first surface member  20 , thereby permitting complete container insertion. 
     In preferred embodiments, housing member  14  and base  16  are essentially rigid, injected molded components having limited resilience in their thinner sections. Housing member  14  is also preferably formed from a clear plastic such as polycarbonate or SAN. In contrast, inlets  34  and  36  are preferably fabricated from a distinctly elastomeric, resilient molding material such as silicone rubber. 
     Housing member  14  and base  16  are configured such that they may only be assembled in one direction, so in use, the operator cannot assemble the device incorrectly. Base  16  and housing member  14  may also color-coded to indicate which side is for the thrombin container in which side is for the fibrinogen container. Furthermore, base  16  may labeled with a “T” indicating the side for thrombin, and an “F” indicating the side for fibrinogen. Once housing member  14  is snapped onto base  16 , containers  54  and  56  can be brought into the sterile field. 
     The assembly of the components of filling device  10  can take place at a factory or other such manufacturing facility prior to use of the inventive device. The housing member  14  generally may be comprised of a first housing member half  14   a  and a second housing member half  14   b , each being molded to dispose the recesses required for fluid channels  46  and  48  and, if required, drawing tube recesses  88  and  90 . Drawing tubes  42  and  44  are mated with fluid channels  46  and  48 . The assembly is then snugly fitted within the channels formed in the housing member half such that drawing tubes  42  and  44  all are disposed within the void forming one half of the receiving aperture  22 . Once the drawing tubes and fluid channels are in place, first-half  14   a  and second-half  14   b , of housing member  14  are configured to be assembled together by snap fit members, thereby forming the receiving aperture  22 . Alternatively, ultrasonic welding, glue, press fitting or any other method of assembly may be used. All of the components of the inventive device are then sterilized. When it is desired to use the inventive filling device the operator need only insert the containers and mate the housing member onto the base. 
     Generally, the agent containers are not sterilized and are unable to be brought into a sterile environment without risk of contamination. However, when the agent containers are shrouded within the inventive filling device the assembly may be brought into a sterile environment for use. 
     To utilize the present invention, the direct filling device  10 , as shown in FIG. 4, is connected to syringe applicator  18 . Syringe applicator  18  is placed over the filling device such that the syringes of the applicator are approximately centered over and sealably interact with inlet ports  34  and  36 . The novel shaping of the collar  15  allows filling device  10  to mate with syringe applicator  18  in only one orientation, thereby “keying” the fill device to the applicator. The general shape fits to the syringe applicator body in the same manner as interchangeable applicator tips or heads, which are used for droplet or spray dispensing of sealant. Furthermore, the general shape provides a support during the filling device  10  and syringe applicator  18  mating process. The feature of keying the filling device collar  15  to the applicator ensures the proper fibrin components are delivered to their respective reservoirs without significant risk of cross-contamination, particularly when refilling. The collar  15  may be manufactured to functionally attach to a plurality of syringe-type applicators, including without limitation, the DUPLOJECT™ device manufactured by the Baxter Corporation. 
     The operator then assembles the device by sliding the agent containers  54  and  56  onto horizontal container supports  66  and  68  such that the containers are supported by the necks of the two agent containers. FIG. 7 shows an additional embodiment of the present invention the horizontal angled support comprises a multiple angle planar surface, wherein the horizontal container support surface  66  and  68  comprises a distal portion  66   a  and  68   a  substantially parallel to the angular stop  32 , a medial portion  66   b  and  68   b  substantially parallel to base plate portion  62 , and a proximal portion  66   c  and  68   c  substantially parallel angular stop  32 . The angled distal portions  66   a  and  68   a  and proximal portions  66   c  and  68   c  are angled such that friction will not stop the container from fully seating on level medial portions  66   b  and  68   b . As stated previously, the bottle supports, generically referred to as  66  and  68 , may form a single planar surface. Once the containers are properly seated, the housing member  14  is placed over the base  16 . As the housing member  14  is lowered onto the base  16  drawing tubes  42  and  44  pierce the container septum and hinged drawing tube supports  80  and  82  are folded into recesses  88  and  90  formed on the first surface  20 . As the housing member  14  is further lowered onto the base  16  the tops of containers  54  and  56  come into contact with the biasing member  30 , thereby causing the containers  54  and  56  to tilt. Ideally, the pointed ends,  50  and  52 , of the drawing tubes  42  and  44  are shaped such that they conform to the shape of the bottom corner of the agent containers enabling withdrawal of substantially all the agent from the container. 
     Once the housing member  14  has been completely lowered onto the base  16  into the fully engaged position, it may be locked into place by base locking member  70 . Agent containers  54  and  56  are tilted in such a manner that drawing tubes  42  and  44  are forced into the bottom corner of each respective container, which has now become the low point for the agent to pool into. This configuration along with the shaping of the drawing tubes allows for minimal waste of the agent contained within the containers. 
     Once the inventive filling device is assembled, it may be brought into a sterile field. Although, the agent containers are generally not sterile and therefore would not be allowed within a sterile environment for risk of contamination, the housing member and base assembly has effectively shrouded the containers within a sterile environment so that they may be brought into a sterile field. 
     Although only two containers are depicted for use with the inventive filling device, adaptation can be easily made to allow the use of one or more containers which can directly fill one or more reservoirs contained within the applicator. This adaptation can be accomplished by decreasing or expanding the housing member and adding or eliminating inlet ports, transverse channels and drawing tubes. 
     While illustrative embodiments of the invention have been described above, it is, of course, understood that various modifications will be apparent to those of ordinary skill in the art. Many such modifications are contemplated as being within the spirit and scope of the invention.