Abstract:
The present invention is directed to devices for mixing and expressing a multi-component sealant or hemostat or adhesive comprising at least two containers configured to contain and express two reactive components into separate lumens of a cannula. An elongated expression tip having a main channel that is open at a proximal end with the cannula slidably fits into the main channel. The tip contains a plurality of separate mixing chambers open at the distal end of the tip, wherein each of the mixing chambers is in fluid communication with the main channel via an individual connecting channel. Openings for each of the connecting channels are provided at different distances from the distal end. The tip is configured to slide on the cannula and advance distally when the main channel is pressurized due to an obstruction in at least one of the mixing chambers.

Description:
FIELD OF THE INVENTION 
     The present disclosure relates to drip or spray tip assemblies for use with devices that mix and apply two or more components. More particularly, the present disclosure relates to a tip assembly, wherein the tip automatically, semi-automatically, or manually changes to a fresh mixing chamber and it thus is capable of redirecting flow when clogging occurs. 
     BACKGROUND 
     Drip or spray devices for dispensing two or more synthetic or biologics based sealant components are known. In the medical device field, such devices are typically used for applying bioadhesives, polymers and other synthetic materials used as wound closures. Because of the reactant nature of the biocomponents used to form the bioadhesive blends, mixing of the components does not occur until the solution is ready to be applied. Mixing of the components too soon before application may result in premature hardening of the mixture, thereby making application of the solution impossible. Thus, in known spray or drip devices, the two or more components are maintained separately until just prior to application. The drip devices include one or more mixing means for mixing the two or more components prior to application. The mixing means may be passive, i.e., spiral configuration in the tubing, or instead may be active, i.e., mixing blade or impeller, with active mixing requiring more complex devices design. Once mixed, the solution may be applied through a needle-like output or may instead be ejected through a spray assembly. Thorough mixing of the two or more components prior to application is important to ensure that the solution will perform as intended. 
     An exemplary device is taught in U.S. Pat. No. 5,116,315, entitled “Biological Syringe System”, which discloses a system for delivery two fluids in a mixed composition, comprising a manifold and a discharge assembly. The discharge assembly mixes fluids in a mixing space and then atomizes the mixed fluids in a spray delivered from the assembly. Similarly, the device shown in U.S. Pat. No. 5,605,255, entitled, “Apparatus for Spraying a mixture of Two Components”, is an apparatus for spraying a liquid mixture having two syringes, a connecting piece, a premixing chamber, and a reduced volume section downstream from premixing chamber, and an exit aperture for spraying the mixture. The reduced volume section terminates in a homogenization region. U.S. Pat. No. 6,063,055, entitled “Turbulence Mixing Head for a Tissue Sealant Applicator and Spray Head for Same”, illustrates a device in which the mixing is performed in a mixing head. 
     Intermittent use of a biologics spray device, as may be required during a procedure, tends to clog the outlet of the applicator tip. As a result, most applicator assemblies are provided with a number of replacement tips for use when clogging of the tip occurs. Replacing clogged applicator tips interrupts the flow of a procedure, is time consuming and is an added expense. The device in published U.S. Publication 2010/0096481, “Self-Cleaning Spray Tip”, is described as having the distal end of spray cap assembly with an outlet that changes its configuration—at rest and at a second condition (e.g. during expression). The distal end is described as comprised of a material that permits flexion and expansion. The first and second reactive components are introduced into swirl chambers before mixing and are atomized as ejected through the outlet in a cone-shaped spray 
     U.S. Pat. No. 5,605,541 “Fibrin sealant applicator” discloses a device for applying a fibrin sealant comprising two components which will form said sealant when combined, which device comprises commonly actuable reservoirs for each of said components and a source of gas, wherein each of said reservoirs and said gas in separate fluid communication via a discrete channel to a spray head, said spray head having a first aperture located centrally in an exit end of said spray head through which said gas is discharged, said spray head having a first annular aperture in the exit end of said spray head within first annular aperture is concentric with said first aperture and through which one of said fibrin-sealant-forming components is discharged, and a second annular aperture in the exit end of said spray head being concentric with said first aperture and concentric with, and having a radius larger than said first annular aperture through which the second of said fibrin-sealant-forming components is discharged wherein all of said apertures are in a common plane. 
     U.S. Pat. No. 6,773,414 “Device and method for dispensing at least two mutually reactive components” discloses a device for dispensing at least two mutually reactive components, comprising a component supplier having primary channels for supplying respective ones of said at least two reactive components to a component dispenser having secondary channels for separately discharging said at least two reactive components through orifices opening into a free target area at a distal tip end of the dispenser for external intimate mixing of the respective reactive components outside a distal tip end of said dispenser, wherein distributors are interposed between said primary and secondary channels for multiplying the number of each respective primary channel with at least a factor  2 , adjacent ones of said orifices of said secondary channels being adjoined to said primary channels intended for supply of reactive components of different kind. 
     U.S. Pat. No. 7,018,357 “External mixer assembly” discloses a fluid delivery system for dispensing a multicomponent biological adhesive having at least a first component and a second component, the system comprising: 
     a housing configured to receive a plurality of reservoirs; 
     a discharge nozzle housing a conduit assembly having a plurality of conduits with a proximal end thereof in respective fluid communication with separate of said reservoirs, a distal end of said conduits defining at least two exit openings, wherein each of said plurality of reservoirs includes a sealable opening configured for being penetrated by a proximal end of a respective one of said plurality of conduits; and
 
a deflector assembly provided on said housing, said deflector assembly having a deflector plate substantially parallel with said at least two exit openings, said deflector plate displaced at a distance from a distal-most end of said housing and oriented to deflect said first and second components after exiting from said at least two exit openings.
 
     U.S. Pat. No. 8,616,468 “Spray applicator” discloses a spray assembly for dispensing a mixture, the assembly comprising: a connector configured for operable engagement with a first source of component and a second source of component; an elongated member operably connected to and extending distally from the connector, the elongated member including an inner shaft and an outer sleeve, and defining a vent lumen between the inner shaft and outer sleeve, the inner shaft defines at least a first lumen configured for fluid communication with the first source of component and a second lumen configured for fluid communication with the second source of component; a tip operably connected to the connector, the tip including an opening and defining a mixing chamber between a distal end of the elongated member and the opening of the tip; and an insert member configured to be received in the mixing chamber, the insert member defining at least one radially extending slot on a first end of the insert member and at least one radially extending slot on a second end of the insert member, each of the radially extending slots being configured to mix the first and second components prior to the combination exiting the opening in the tip. 
     There is a need in conveniently changing spray or drip tips to avoid procedure interruption if/when clogging of the tip occurs. Particularly in laparoscopic procedures, clogged tips may result in significant and undesirable delays in delivery of the sealant or hemostat. 
     SUMMARY OF THE INVENTION 
     Briefly, the present invention is directed to a device for mixing and expressing a multi-component sealant or hemostat or adhesive comprising at least two containers configured to contain and express two components into separate lumens of a multi-lumen cannula without mixing; an elongated expression tip having a main channel open at a proximal end with the cannula configured to slidably fit into the main channel; the tip containing a plurality of separate mixing chambers open at the distal end of the tip, each of the mixing chambers being in fluid communication with the main channel via an individual connecting channel at some position of the tip on the cannula; wherein the connecting channels openings into the main channel all having different distances from the distal end; wherein the tip is configured to slide on the cannula and advance distally when the main channel is pressurized. 
     In another aspect, the present invention is directed to a method of mixing and expressing a multi-component sealant or hemostat or adhesive comprising connecting at least two containers configured to contain and express two components to separate lumens of a multi-lumen cannula; connecting an elongated expression tip having a main channel open at a proximal end to the cannula, wherein the cannula is configured to slidably fit into the main channel; wherein the tip contains a plurality of separate mixing chambers open at the distal end of the tip, each of the mixing chambers being in fluid communication with the main channel via an individual connecting channel at some position of the tip on the cannula; wherein the connecting channels openings into the main channel all having different distances from the distal end; advancing the two components through separate lumens of the multi-lumen cannula without mixing to the tip, mixing the two components within a first mixing chamber and expressing the components through a first opening at the distal end of the tip; upon clogging of the first mixing chamber, continue advancing the two components through separate lumens of the multi-lumen cannula thus pressurizing the main channel; allowing the tip to slide on the cannula and advance distally thus opening a second mixing chamber to fluid communication with the main channel, mixing the two components within the second mixing chamber and expressing the components through a second opening at the distal end of the tip. 
    
    
     
       BRIEF DESCRIPTION OF FIGURES 
         FIGS. 1A and 1B  show perspective views of the inventive device for mixing and expressing multi-component compositions. 
         FIG. 2  shows a schematic cross-sectional view of the inventive device for mixing and expressing multi-component compositions. 
         FIG. 3  shows a schematic cross-sectional view of the inventive device for mixing and expressing multi-component compositions. 
         FIG. 4  shows a schematic cross-sectional view of the inventive device for mixing and expressing multi-component compositions. 
         FIG. 5  shows a schematic cross-sectional view of a portion of the inventive device for mixing and expressing multi-component compositions. 
         FIG. 6  shows a schematic cross-sectional view of the inventive device for mixing and expressing multi-component compositions. 
         FIGS. 7A-C  show schematic cross-sectional views of a portion of the inventive device for mixing and expressing multi-component compositions. 
         FIG. 8  shows a schematic perspective view of a portion of the inventive device for mixing and expressing multi-component compositions. 
         FIG. 9  shows a schematic perspective cross-sectional view of a portion of the inventive device for mixing and expressing multi-component compositions. 
         FIG. 10  shows a schematic frontal view of a portion of the inventive device for mixing and expressing multi-component compositions. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring now to  FIG. 1B , an embodiment of a device  10  for mixing and expressing a multi-component sealant or hemostat or adhesive (or composition having one or more of these properties) is shown, comprising two or more containers or syringes  20  containing components of multi-part sealant or hemostat or adhesive, connected to a multi-lumen cannula  30  to which tip  100  having a plurality of exit ports  50  is attached. 
     Referring now to  FIG. 2 , an embodiment of device  10  is shown in more detail, with syringe  21  containing a first component  22  and syringe  23  containing a second component  24 , syringes  21  and  23  having optionally interconnected plungers  25  for simultaneous expression of components  22  and  24 . Syringes  21  and  23  are connected to multilumen cannula  30  via connectors  28  and  29 , so that first component  22  and second component  24  can advance in multilumen cannula  30  towards tip  100  through lumens  26 ,  27  without mixing, thus preventing clogging of the multilumen cannula  30 . In the shown embodiment, multilumen cannula  30  is a dual lumen cannula. Multilumen cannula  30  can have an additional lumen for gas (not shown) for gas-assisted spray. 
     Elongated tip  100  has a proximal end  101  that is closer to syringes  21  and  23  and an opposing distal end  102  relative to syringes  21  and  23 . Ports  51 ,  52 , from which the expression of the mixed liquid first component  22  and liquid second component  24  forming sealant or hemostat or adhesive are situated at distal end  102 . Tip  100  has an axial main channel  110  open at proximal end  101  with cannula  30  configured to slidably fit into main channel  110  so that tip  100  is slidably moveable on cannula  30  and can advance distally when main channel  110  is pressurized due to clogging. 
     Tip  100  has a plurality (two are shown in the embodiment of  FIG. 2 ) of separate mixing chambers  121 ,  122 , open at distal end  102  of tip  100  to ports  51 ,  52  respectively. Each of mixing chambers  121 ,  122  are in fluid communication with main channel  110  via an individual connecting channel  131 ,  132  respectively. Connecting channels  131 ,  132  are open into main channel  110  at different distances from distal end  102 , with distance of connecting channel  131  from distal end  102  D 1  is indicated by arrow D 1  and distance of connecting channel  132  from distal end  102  D 2  is indicated by arrow D 2 . Distances D 1  and D 2  being different by at least the width of connecting channels  131 ,  132  and preferably by more than the width of connecting channels. 
     In some embodiments, lumens  26 ,  27  of multilumen cannula have inside diameter of 0.2-2 mm, such as 0.3 mm, 0.5 mm, 0.7 mm, 1 mm, 1.5 mm. Outside diameter of multilumen cannula  30  is 0.5-10 mm, such as is 1 mm, 1.5 mm, 2 mm, 3 mm, 5 mm, 7 mm, 10 mm. Inside diameter of main channel  110  corresponds to outside diameter of multilumen cannula  30 , i.e. 0.5-10 mm, such as close to or slightly larger than 1 mm, 1.5 mm, 2 mm, 3 mm, 5 mm, 7 mm, 10 mm. Inside diameter of mixing chambers  121 ,  122  is 0.7-3 mm, such as 1 mm, 1.5 mm, 2 mm, 3 mm. Inside width of connecting channels  131 ,  132  is 0.3-3 mm, such as 0.5 mm, 0.7 mm, 1 mm, 1.5 mm, 2 mm. Distance D 1  differs from distance D 2  by more than width of connecting channels  131 ,  132  such as by 1.5-3 mm when diameter of connecting channels  131 ,  132  is 1 mm. 
     In some embodiments, two-part compositions comprise biological adhesive or sealant, forming fibrin glue, whereby first component  22  is fibrinogen and second component  24  is thrombin or thrombin analog or precursor. In other embodiments first component  22  is cross-linkable synthetic component, and second component  24  is a cross-linking agent. 
     Referring now to  FIG. 3 , in operation with connected plungers, depressing plungers  25  results in simultaneous advancing first component  22  and second component  24  through lumens  26  and  27  of multilumen cannula  30  towards tip  100  without mixing. First component  22  and second component  24  then enter connecting channel  131  and first mixing chamber  121 , where first component  22  and second component  24  commingle and intermix to form a blend for sealant or hemostat or adhesive upon mixing. As shown by arrow A, the blend of first component  22  and second component  24  while undergoing additional mixing advance towards distal end  102  of tip  100  and exit tip  100  through port  51  toward targeted tissue, organ or wound (not shown). Exiting sealant or hemostat or adhesive formed through the blending and mixing of first component  22  and second component  24  can be expressed as a drip or as a spray, or combinations thereof. 
     The expression of sealant continues through port  51  as needed. Upon interruption of expression through port  51 , due to operational activities such as performing another procedure, repositioning or retargeting device  10 , etc., clogging connecting channel  131  and first mixing chamber  121  might occur due to gelling properties of the components. Such situation is shown in  FIG. 4 , with clog  200  forming in first mixing chamber  121 . As a result of clog  200  blocking exit of the mixture of first component  22  and second component  24  from device  10  via port  51 , upon health practitioner trying to restart expression and depressing plungers  25 , pressure inside tip  100  increases. The pressure buildup is due to liquid components  22  and  24  having no path way for exiting tip  100  due to blockage by clog  200 . 
     Referring now to  FIG. 5 , where for simplification purposes, syringes  21  and  23  are not shown, increase in pressure results in sliding advancement of tip  100  distally, with tip  100  sliding on multilumen cannula  30  and opening a new portion of main channel  110  to the second connecting channel  132 . The previous location of tip  100  corresponding to  FIGS. 2-4 , is schematically indicated by dashed box  100   a . The distal advancement of tip  100  as shown in  FIG. 5  opens a path for components  22  and  24  from main channel through connecting channel  132  and into second mixing chamber  122 . 
     As shown by arrow “B”, despite clot  200 , first component  22  and second component  24  can exit multilumen cannula  30  by advancing through connecting channel  132  and second mixing chamber  122  to commingle and intermix and form a blend for sealant or hemostat or adhesive. Mixed first component  22  and second component  24  while undergoing further mixing advance towards distal end  102  of tip  100  and exit tip  100  through second port  52  toward targeted tissue, organ or wound (not shown). 
     As shown above, clogging of a first connecting channel  131 , and/or mixing chamber  121 , and/or port  51  resulted in automatic change to second connecting channel  132 , mixing chamber  122 , and port  52 . Advantageously, there is no need in manual tip  100  de-clogging, tip  100  replacement, or device  10  replacement during the treatment. 
     Embodiments described operate so as to switch to an unclogged mixing chamber automatically, meaning that the action occurred primarily as a result of internal pressure that caused a displacement and redirection of fluid flow. In another aspect, switching to an unclogged mixing chamber can be effected semi-automatically or manually. In semi-automatic operation, whereby practitioner manually advances and/or turns tip  100  to switch to second connecting channel  132 , mixing chamber  122 , and port  52 . 
     Referring now to  FIG. 6 , an embodiment of device  10  similar to embodiments shown in  FIGS. 2-5  is presented, with tip  100  having four connecting channels  131 ,  132 ,  133 ,  134 , in fluid communication with corresponding mixing chambers  121 ,  122 ,  123 ,  124 , terminating at distal end  102  in corresponding exit ports  51 ,  52 ,  53 ,  54 . Similarly to embodiments shown in  FIGS. 2-5 , upon clogging of first mixing chamber  121  and/or corresponding connecting channel  131  and/or corresponding port  51 , tip  100  automatically advances distally opening main channel  110  to second connecting channel  132  in fluid communication with corresponding mixing chamber  122 , terminating at distal end  102  in corresponding exit port  52 . Upon clogging of second mixing chamber  122  and/or corresponding connecting channel  132  and/or corresponding port  52 , tip  100  further advances distally opening main channel  110  to third connecting channel  133  in fluid communication with corresponding mixing chamber  123 , terminating at distal end  102  in corresponding exit port  53 . Upon clogging of third mixing chamber  123  and/or corresponding connecting channel  133  and/or corresponding port  53 , tip  100  further advances distally opening main channel  110  to fourth connecting channel  134  in fluid communication with corresponding mixing chamber  124 , terminating at distal end  102  in corresponding exit port  54 . While embodiment of  FIG. 6  shows four mixing chambers and exit ports, any number of such components can be incorporated into tip  100 , e.g. three to ten mixing chambers and exit ports, such as five. 
     Spring  300  connecting tip  100  to structure  310  affixed below syringes  21  and  23  provides resistance to tip  100  moving distally and controlling tip motion in distal direction. Elements  129  shown in mixing chambers  121 - 124  are optional static mixing elements or baffles facilitating intermixing of first component  22  and second component  24 . 
     Referring now to  FIGS. 7A-C , for simplification purposes, syringes  21  and  23  are not shown. In  FIG. 7A , device  10  is shown with the expression proceeding through port  51 . Upon formation of clog  210  as illustrated in  FIG. 7B , tip  100  advances by distance  60  distally and expression continues through port  52 . Upon formation of clog  220  as illustrated in  FIG. 7C , tip  100  advances by distance  61  distally and expression continues through port  53 . 
     Referring now to  FIG. 8 , for simplification purposes, syringes  21  and  23  are not shown. Tip  100  is shown in a prospective view, mounted on multilumen cannula  30 , with five ports  51 ,  52 ,  53 ,  54 ,  55  providing expression outlets from tip  100 . 
     Referring now to  FIG. 9 , for simplification purposes, syringes  21  and  23  are not shown. Tip  100  is shown in a prospective cross-sectional view, mounted on multilumen cannula  30 , with four ports  51 ,  52 ,  53 ,  54  visible and in fluid communication with four mixing chambers  121 ,  122 ,  123 ,  124  visible, having static mixers  129  in mixing chambers. Fifth mixing chamber and port are not visible in the cross-sectional view. 
     Referring now to  FIG. 10 , for simplification purposes, syringes  21  and  23  are not shown. Tip  100  is shown in a frontal view, with five ports  51 ,  52 ,  53 ,  54 ,  55  visible. 
     Having shown and described various versions in the present disclosure, further adaptations of the methods and systems described herein may be accomplished by appropriate modifications by one of ordinary skill in the art without departing from the scope of the present invention. Several of such potential modifications have been mentioned, and others will be apparent to those skilled in the art. For instance, the examples, versions, geometrics, materials, dimensions, ratios, steps, and the like discussed above are illustrative and are not required. Accordingly, the scope of the present invention should be considered in terms of the following claims and is understood not to be limited to the details of structure and operation shown and described in the specification and drawings.