Patent Publication Number: US-2021186812-A1

Title: System for Recovering Autologous Thrombin

Description:
RELATED APPLICATION 
     This application claims the benefit of Provisional Application Ser. No. 62/949,832 filed Dec. 18, 2019. 
    
    
     FIELD OF THE INVENTION 
     This invention relates to an improved apparatus and method for recovering an autologous thrombin solution from a sample of an individual&#39;s blood, which can then be used to promote clotting and activate PRP growth factors in conjunction with dental and orthopedic surgical procedures. 
     BACKGROUND OF THE INVENTION 
     Thrombin is a blood enzyme that is useful for activating procoagulant and platelet rich plasma (PRP) growth factors needed during dental and orthopedic surgeries. Thrombin is present in both human and animal blood. Traditionally, bovine thrombin has been utilized for clotting and activating the growth factors of PRP employed in surgical procedures. However, the results of using enzymes derived from this source have been less than optimal. Moreover, mad cow disease has presented a serious health risk that has made the use of bovine derived thrombin much less desirable. 
     Recently, the use of autologous thrombin derived from the patient&#39;s own blood has become the preferred manner of obtaining the thrombin enzyme. Typically, a sample of the patient&#39;s blood is drawn and allowed to clot in a petri dish or other appropriate container. The blood product is centrifuged to separate a yellow thrombin solution from the clot. The thrombin solution or supernatent is then aspirated and calcium, in the form of calcium chloride, is added to the solution to yield the final blood clotting thrombin product. 
     The foregoing process exhibits a number of disadvantages. It is both unduly time consuming and involves a number of discrete steps that must be precisely performed. A centrifuge and a source of calcium are both required. Moreover, the thrombin supernatant that is produced is often of a poor quality and does not provide for the desired clotting and growth activation factors. As a result, the results obtained by using such autologous thrombin in dental and surgical procedures is frequently less than optimal. 
     SUMMARY OF THE INVENTION 
     It is therefore an object of the present invention to provide an apparatus and method for recovering a high-quality autologous thrombin solution from an individual&#39;s blood, which overcomes the problems exhibited by prior art techniques. 
     It is a further object of this invention to provide an apparatus and method for recovering an improved high-quality autologous thrombin that activates procoagulant factors and PRP growth factors much more effectively than has been achieved using previously produced thrombin solutions. 
     It is a further object of this invention to provide a much simpler and more efficient system for producing autologous thrombin that reduces the time, complexity, equipment, supplies and steps conventionally needed to produce autologous thrombin for surgical procedures. 
     It is a further object of this invention to provide a system for recovering a very high quality and effective autologous thrombin for use in dental and orthopedic surgical procedures. 
     It is a further object of this invention to provide a system for recovering a high-quality autologous thrombin that effectively clots to reduce excessive bleeding during surgery and which activates PRP growth factors to more effectively seal and repair bones and stimulate bone growth and recovery. 
     It is a further object of this invention to provide a system for recovering autologous thrombin that is safer and more effective for use in surgery than conventional bovine thrombin solutions and more efficient and effective than previous autologous thrombin products. 
     It is a further object of this invention to provide a method for recovering a high-quality autologous thrombin solution, which exhibits a higher purity and eliminates much of the fibrous clotting materials and blood cells that are present in conventional autologous thrombin solutions. 
     This invention features an autologous thrombin recovery system including injecting and aspirating syringes and a filter assembly operably interconnected between the injecting and aspirating syringes. The injecting syringe includes a cylindrical supply receptacle for holding a blood product and having a discharge port formed therein. A first piston assembly is operatively interconnected with the supply receptacle of the injecting syringe. The aspirating syringe includes a receiving receptacle having a fluid inlet port formed therein and a second aspirating piston assembly operatively interconnected thereto. The filter assembly includes a fluid intake port for communicably connecting to the discharge port of the injecting receptacle and a fluid outlet port for communicably connecting to the inlet port of the aspirating syringe. A filter component is disposed between the intake and outlet ports of the filter assembly. In operation, the first piston assembly of the injecting syringe is manually driven through the supply receptacle of the injecting syringe and the aspirating syringe is simultaneously operated by withdrawing or retracting the second piston assembly through the receiving receptacle of the aspirating syringe. This causes blood product to be transmitted through the filter component of the filter assembly such that clotted and fibrous material, as well as red blood cells are removed from the blood product by the filter component. A solution of platelet rich plasma (PRP) and thrombin are thereby collected in the receiving receptacle of the aspirating syringe. This collected thrombin solution may then be used for various dental and orthopedic surgical applications. 
     In a preferred embodiment, the discharge port of the injecting syringe and the inlet port of the aspirating syringe include male luer ports. The intake port of the filter assembly may include a female luer port. The outlet port of the filter assembly may include a male luer port. A connector fitting having a pair of female luer port connections may be used to connect the male outlet port of the filter assembly to the male inlet port of the aspirating syringe. One of the female luer port connections of the connector fitting may be attached to the outlet port of the filter assembly and the other female luer port connector may be communicably secured to the inlet port of the aspirating syringe. The female connections of the connector fitting are themselves communicably interconnected. As a result, when the first piston assembly of the injecting syringe is depressed through the supply receptacle and the second piston assembly of the aspirating syringe is simultaneously retracted, blood product is dispensed through the male discharge port of the injecting syringe and transmitted through the interconnected intake port of the filter assembly. The filter component separates the coagulated, fibrous and cellular matter from the blood product. A high-quality thrombin and plasma solution is then transmitted through the outlet port of the filter assembly, through the connector fitting and through the attached inlet port of the aspirating syringe into the receiving receptacle of that syringe. 
     The injecting syringe preferably includes a glass supply receptacle, which promotes coagulation of the blood. After blood product is introduced into the supply receptacle, it may be agitated for a predetermined time to further facilitate coagulation prior to operation of the system. 
     The filter component may include a hydrophilic filter. The filter preferably includes a pore size of approximately 0.2 microns. In any event, the filter component should include-pores having a size not larger than 0.45 microns apiece. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Other objects, features and advantages will occur from the following description of a preferred embodiment and the accompanying drawings, in which: 
         FIG. 1  is an elevational schematic view of the system for recovering autologous thrombin in accordance with this invention and wherein a blood product is contained in the injecting syringe of the system before the filtering operation is performed; and 
         FIG. 2  is a view similar to  FIG. 1  of the system after the filtering operation step has been performed and with a purified and high-quality plasma/PRP thrombin solution contained in the aspirating syringe. 
     
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     There is shown in  FIG. 1  an apparatus  10  for recovering autologous thrombin in accordance with this invention. In particular the apparatus and method of this invention are intended for retrieving an improved, high-quality thrombin solution (comprising the enzyme thrombin in solution with plasma and platelet rich plasma). The thrombin activates the clotting or anticoagulation factors of the blood, as well as the PRP growth factors present in the solution. As a result, the solution is extremely effective for use in a variety of dental and orthopedic surgical procedures where bone repair and growth are desired. The particular type of surgical procedure for which the thrombin solution may be used is not a limitation of this invention. 
     Autologous thrombin solution is recovered from a patient undergoing a dental or orthopedic surgical procedure using a system comprising apparatus  10  depicted schematically in  FIGS. 1 and 2  operated in accordance with the method of this invention. In particular, apparatus  10  includes a pair of hypodermic syringes  12  and  14  that are operably and communicably interconnected by a filter assembly  16 . Syringes  12  and  14  preferably comprise sterile medical grade syringes suitable for use in processing blood and other biological liquids. Syringe  12  constitutes an injecting syringe and includes a generally cylindrical supply receptacle  18 , which is preferably composed of glass. As is described more fully below, the glass receptacle promotes clotting of the blood product B within receptacle  18  when the method of this invention is practiced. Injecting syringe  12  also includes a standard first piston assembly featuring a diaphragm, disc or piston  20  that is slidably and sealably mounted within receptacle  18  such that the peripheral surface of the piston sealably interengages the inner wall of receptacle  18  and is slidable back and forth through the receptacle. Piston  20  is driven through receptacle  18  by a manually operated plunger  22  that is mounted within the receptacle  18  of syringe  12  in a conventional manner. 
     Injecting syringe  12  also includes a discharge port  24 , which preferably features a male luer port having a threaded connective tip  26  of the type that will be known to persons skilled in the art. Discharge port  24  is formed at the lower or distal end of supply receptacle  18  and communicably interconnected with an interior chamber of the receptacle. Tip  26  allows syringe  12  to be operatively interconnected to filter  16  in the manner described below. 
     Second syringe  14  comprises a receiving or aspirating syringe that may have a configuration or construction identical or similar to that of injecting syringe  12 . In particular, syringe  14  includes a cylindrical fluid-receiving receptacle  28 . Each of syringe receptacles  18  and  28  may have various capacities within the scope of this invention. Syringe  14  operatively supports a second piston assembly comprising a diaphragm, disc or piston  30  that is slidably and sealably mounted within the interior chamber of receptacle  28 . A plunger  32  is operatively mounted to piston  30  and extends outwardly from the upper or proximal end of receptacle  28 . Plunger  32  is pulled rearwardly or retractably to draw piston  30  through receptacle  28  so that aspiration is performed in the manner described more fully below. 
     Aspirating syringe  14  likewise includes a male luer port  34  that communicates with the interior chamber of receptacle  28  and is carried at the lower or distal end of that receptacle. Luer port  34  includes a threaded tip  36  that, again, allows syringe  14  to be operatively interconnected to filter assembly  16  in the manner described below. Port  34  thereby serves as an inlet port of aspirating syringe  14 . 
     Syringes  12  and  14  are operatively interconnected by filter assembly  16 . More specifically, the filter assembly includes a hydrophilic filter  38  featuring a pore size that is not larger than 0.45 microns. A particularly preferred pore size is 0.2 microns for most effectively performing the thrombin recovery process of this invention. 
     A filter intake port  40  is communicably connected to a first side of hydrophyllic filter  38  and a filter outlet port  42  is likewise communicably connected to the opposite side of filter  38 . Filter intake port  40  preferably comprises a female luer-type connective port that is threadably or otherwise operatively interconnected to male discharge port  24  of injecting syringe  12 . Filter outlet port  42  likewise preferably comprises a male luer port. An internal passageway  41  is formed in intake port  40  of filter assembly  16 , which permits blood product to be transmitted from syringe  12  to filter component  38  as described more fully below. Filter assemblies featuring intake and outlet ports and an intervening filter, as specified herein, are conventionally available to persons skilled in the art. Such filter assemblies are used in IV circuits, for example, to vent and filter air and restrict contamination in an IV line. Alternatively, constructing such assemblies will be understood by such persons. 
     Male outlet  42  of filter assembly  16  is operatively and communicably interconnected to male inlet port  34  of syringe  14  by means of a coupler or connector fitting  44  having a pair of opposing and communicably interconnected female luer ports  46  and  48 . Each port  46 ,  48  includes interior threads that are connected to corresponding threads on tips  43  and  36  of male luer ports  42  and  34  respectively. This allows the aspirating syringe  14  to be securely and communicably interconnected to filter assembly  16  through connector fitting  44 . A central passageway  50  formed through fitting  44  allows filtered supernatant solution to be transmitted through the connector fitting between filter outlet  42  and syringe inlet port  34 . Without connector fitting  44  featuring a pair of opposing and communicating female ports, the aspirating syringe would be unable to operatively interconnect with a filter assembly of the type represented by assembly  16 . Preferably, respective receptacles  18  and  28  of syringes  12 ,  14  are permanently enclosed and liquids are introduced and discharged from the syringes by conventional injection and aspiration operations performed using the first and second piston assemblies respectively. Alternatively, it should be noted that, each syringe  12 ,  14  may include a cap or closure that is selectively opened and closed, as needed, to introduce and remove blood products and filtered thrombin solution to and from the syringes respectively when the system is used in accordance with this invention. 
     System  10  is employed to recover autologous thrombin from a patient in accordance with the following procedure. Initially, a sample of the patient&#39;s blood is drawn into receptacle  18  of syringe  12  and the syringe is capped. The blood can be drawn into the syringe in a standard manner or in alternative ways that are sterile and medically acceptable. The blood product B ( FIG. 1 ) is then agitated for a selected duration to promote clotting and typically until a clot forms within receptacle  18 . After clotting occurs in blood product B, syringe  12  is operatively interconnected to intake port  40  of filter assembly  16 . Specifically, exteriorly threaded tip  26  of male luer discharge port  24  is threadably interconnected interiorly threaded with female luer port  40  of filter assembly  16 . 
     Receiving or aspirating syringe  14  is likewise operatively connected to outlet port  42  of filter assembly  16 . In particular, the exteriorly threaded tip  36  of male inlet port  34  is interengaged with the interiorly threaded female port  48  of coupler  44 . By the same token, interiorly threaded female port  46  of coupler fitting  44  is interengaged with exteriorly threaded tip  43  of filter outlet  42 . 
     After the foregoing luer port interconnections are completed, syringes  12  and  14  are operated to transmit blood product B from receptacle  18  of syringe  12  through filter assembly  16  and into receptacle  28  of syringe  14 . Specifically, plunger  22  is actuated or depressed from the position shown in  FIG. 1  to that shown in  FIG. 2 . This drives piston  20  through the interior chamber of supply receptacle  18  of syringe  12 . The clotted blood product is thereby injected through discharge port  24  of syringe  12  and passageway  41  of interconnected filter intake port  40 . Plunger  32  of syringe  14  is simultaneously retracted or withdrawn through receptacle  28  from the position shown in  FIG. 1  to the position shown in  FIG. 2 . This simultaneous dual operation of syringes  12  and  18  pulls the blood product forcefully through filter assembly  16 . Hydrophilic filter  38  traps the clot and effectively removes unwanted constituents such as fibrous material, blood proteins and red blood cells from the blood product. More specifically, the simultaneous dual syringe operation provides a sufficient level of pressure to more easily, smoothly and effectively transmit the blood product through the relatively small pore-size hydrophilic filter, which largely eliminates the clot, fibrous material and red blood cells from the blood product. As a result, a thrombin solution comprising plasma that contains high quality PRP and thrombin enzyme is transmitted through filter outlet  42 , as well as interconnected coupler fitting  44  and inlet port  34  of syringe  14 . As shown in  FIG. 2 , filtered thrombin solution T, comprising plasma, PRP and high-quality thrombin is collected within receptacle  28  of syringe  14 . 
     After filtration is completed, receiving syringe  14  is disengaged from coupler fitting  44 . A concentrated autologous thrombin solution or supernatant remains in the receptacle of the receiving syringe. This supernatant is then retrieved from syringe  16  and mixed with either whole blood or PRP. The thrombin activates clotting and growth factors in the PRP that allow the mixture to be used effectively in a variety of dental and orthopedic surgical applications, including bone sealing, reinforcement, repair and reconstruction. The use of the patient&#39;s own PRP and thrombin achieves results that are far superior to those obtained using thrombin and PRP that are nonautogenous. 
     System  10  and the method of recovering autologous thrombin using that system provide for a number of advantages over the prior art. The disclosed system produces a thrombin solution that is far safer and more effective for use in dental and orthopedic surgical applications than are bovine thrombin products. Medical risks associated with mad cow disease are eliminated. The present invention enables very high-quality autologous thrombin solution to be obtained much faster, more efficiently and using less equipment, time and materials than has previously been involved. Centrifuging the blood product and related centrifuge equipment are not needed. Likewise, this system does not require the addition of calcium to compensate for the anticoagulation effects that normally result when a citrate solution is added to a PRP blood source. 
     By using a glass delivery syringe, the disclosed system also eliminates the use of glass powder for promoting clotting during the autologous thrombin recovery process. The highly concentrated and high-quality thrombin recovered using the apparatus and process of this invention provides for significantly improved surgical and orthopedic results. Bone regeneration, support and recovery are aided considerably. PRP growth factors and clotting are likewise significantly improved by the concentrated thrombin solution. This enables much better bone growth, healing, regeneration and support to be achieved. Various types of dental and orthopedic surgical procedures are thereby benefitted. 
     Accordingly, the present invention relates to a system and method for recovering autologous thrombin by using a hydrophilic filter that is communicably interconnected between a pair of injecting and aspirating syringes. The system is operated to effectively remove fibrous clotting material and red blood cells from a blood sample such that a concentrated and high-quality thrombin solution is recovered for use in PRP related dental and orthopedic surgical applications. 
     Although specific features of the invention are shown in some of the drawings and not others, this is for convenience only, as each feature may be combined with any and ail of the other features in accordance with this invention.