Syringe with double chambers connected in series

Abstract

Dual chamber syringes facilitate selective drug mixing, dosing and administration through catheters or other vascular access devices (VADs), as well as pre-or post-administration irrigation of catheters with a single syringe instrument. A syringe barrel includes an outlet (such as a luer connector), variable volume axial series primary and secondary fluid chambers having nested respective plungers, plunger rods selectively translatable along a common axis within the barrel interior, and plunger plugs. A secondary fluid chamber is included within the primary plunger. A selectively resealable valve disposed within the barrel interior selectively isolates the secondary fluid chamber from fluid communication from the primary fluid chamber and / or the outlet of the syringe barrel. In some embodiments, the valve is a duckbilled valve or an umbrella-shaped valve. In some embodiments, the syringe is pre-packaged with a rinsing solution in the secondary fluid chamber.

Description

Technical Field

[0001] The present disclosure generally relates to a dual-chamber syringe assembly for administering two gases or fluids, or for administering and flushing catheters and other vascular accessing devices (VADs), or for mixing and administering fluids; and a method of flushing a catheter. Background Art

[0002] VADs are commonly used therapeutic devices and include I.V. catheters. VADs generally fall into two categories: peripheral catheters and central venous catheters. If not properly maintained, VADs can become blocked. To ensure proper use of VADs and prevent blockage, practice standards have been established. These standards include cleaning procedures, commonly referred to as flushing procedures or flushing the catheter.

[0003] VAD practice standards generally recommend performing flushing procedures after catheter placement, before fluid infusion, and before and after drug administration, blood sampling, blood transfusion, and parenteral nutrition. The goal of these flushing procedures is to confirm catheter patency, avoid drug incompatibility, ensure complete drug dose administration, prevent thrombus formation, and minimize the risk of bloodstream infection. Flushing procedures require different types and amounts of flushing solutions. Commonly used flushing solutions are saline and / or heparin lock solutions. The type and amount of flushing solution vary depending on the specific type of catheter. A flushing solution volume between 5 ml and 10 ml is most common, but the range can be from 1 ml to 20 ml.

[0004] For flushing procedures, an I.V. line refers to a system that includes a VAD (a set of tubing with a clamp) and can terminate in a port or a valve. The most common type of port is covered by a pierceable septum or a pre-cut septum and is known in the art and sometimes referred to as a "PRN", from the Latin pro re nata, meaning "as needed". The septum is preferably made of rubber or another elastomeric material, which allows insertion of a sharp needle cannula to infuse fluid or withdraw fluid from the catheter. After the needle cannula is withdrawn, the septum seals itself. Ports with pre-cut septa are used with a blunt cannula or the frustoconical end of a syringe barrel. The syringe end or the blunt cannula (which is usually attached to a syringe) is gently pushed through the pre-cut septum to establish fluid communication.

[0005] An I.V. valve (another type of end I.V. access device that does not require a needle with a sharp tip) is activated by the frustoconical end of a syringe barrel to allow fluid communication between the inside of the syringe and the catheter. These valves can include structures for delivering fluid from a storage compartment in the valve to the catheter and are known in the art as positive displacement valves.

[0006] Removing debris or residues is referred to as "flushing" or "irrigation" and prevents the deposition and accumulation of blood, blood residues, and IV medications within a catheter or other VAD device. Such accumulation can lead to partial or complete blockage of the fluid pathway in the catheter system and may also require costly and potentially dangerous methods for flushing the affected catheter or completely replacing the catheter. Typically, such blockage results in treatment interruptions, which can potentially endanger patient care. The accumulation of residues within the catheter can also increase the risk of infection by providing a growth medium for microorganisms.

[0007] As understood by those skilled in the art, flushing techniques involve injecting a flushing solution (e.g., a saline solution) into the VAD to remove debris and blockages. Injection is typically achieved by advancing a plunger rod into a pre-filled syringe barrel, thereby expelling the flushing solution into the VAD. When such techniques are used in conjunction with a catheter, turbulence is introduced within the catheter, thereby dislodging any debris or residues attached to the catheter. Flushing techniques require the application of a substantially constant pressure or force on the plunger rod in the distal direction. Conventional or smooth flushing techniques can also include the application of a substantially linearly increasing or decreasing pressure or force on the plunger rod in the distal direction.

[0008] After flushing, the practitioner can then administer a dose of a medical fluid, which is either in a vial from which it needs to be withdrawn or in a separate pre-filled syringe. However, connecting multiple devices to the VAD introduces connectors into an unsterile external environment, thereby introducing the possibility of transmitting catheter-related bloodstream infections (CRBSIs), which can be costly and potentially fatal. To reduce CRBSI cases and to ensure the proper use and maintenance of the VAD, practice standards have been developed, which include disinfection and cleaning procedures.

[0009] In clinical practice, intravenous medications are administered, followed by IV flushing, typically using two separate syringes.

[0010] There is a need for a syringe assembly that has means for both flushing a VAD and administering a dose of a medical fluid, thereby reducing the risk of CRBSI. There is also a need for such a single syringe for administering intravenous medications, followed by IV flushing, to increase clinician efficiency and to reduce the costs associated with maintaining syringe inventories and medical waste disposal. SUMMARY OF THE INVENTION

[0011] A dual-chamber syringe facilitates selective drug mixing, dosing, and administration through a catheter or other vascular access device (VAD), as well as pre- or post-administration flushing of the catheter with a single syringe instrument. The syringe barrel includes an outlet (such as a Luer connector), a primary variable-volume fluid chamber, and a secondary variable-volume fluid chamber, the primary and secondary variable-volume fluid chambers having nested respective plungers, a plunger rod that is selectively translatable along a common axis within the barrel, and a plunger stopper. The secondary fluid chamber is included within the primary plunger. A selectively resealable valve disposed within the barrel selectively isolates the secondary fluid chamber from the primary fluid chamber and the outlet of the syringe barrel from fluid communication. In some embodiments, the valve is a one-way valve, such as a duckbill valve or an umbrella valve, which prevents backflow into the secondary chamber. The isolated secondary chamber configuration advantageously facilitates the use of pre-packaged drugs or flushing solutions in that chamber. Use of a syringe of the type disclosed herein in medical procedures that require flushing and administering drugs through a catheter or other VAD reduces the need to perform multiple infusions and withdraw multiple single-function syringes. Use of the disclosed syringe advantageously reduces the risk of patient infection, reduces the costs associated with syringe inventory and subsequent waste disposal, and reduces the clinician time required to complete the associated medical procedure.

[0012] One aspect of the present disclosure relates to a syringe comprising a substantially cylindrical barrel defining an inner wall, wherein the barrel has an open proximal end and a distal end. The distal end of the barrel includes a connector, such as a Luer connector, which defines an outlet lumen therethrough that is in fluid communication with the interior of the barrel. The interior of the barrel is defined by the open proximal end, the distal end, and the inner wall of the barrel. The syringe further includes a nested primary plunger and a secondary plunger disposed within the interior of the barrel, having a primary plunger rod and a secondary plunger rod respectively that are selectively translatable within the interior of the barrel along a common axis. A primary stopper is coupled to the distal end of the primary plunger. It has a proximal surface facing the proximal end of the barrel, a distal surface facing the distal end of the barrel, and further defines a through hole between its proximal surface and distal surface that is in fluid communication with the outlet lumen. A secondary stopper is coupled to the distal end of the secondary plunger; it has a distal surface facing the distal end of the barrel. A selectively resealable valve is disposed within the interior of the barrel, axially offset along the common axis towards the distal end of the barrel and away from the distal surface of the secondary stopper. The resealable valve has an inlet in fluid communication with the distal surface of the secondary stopper and an outlet in fluid communication with the through hole of the primary stopper and the outlet lumen. The syringe has a variable volume main fluid chamber within the interior of the barrel, defined between the distal surface of the primary stopper and the distal end of the barrel. The volume of the main fluid chamber can be selectively changed by translation of the primary plunger rod. The syringe further has a variable volume secondary fluid chamber within the interior of the barrel, defined between the distal surface of the secondary stopper and the valve inlet. The secondary fluid chamber is in fluid communication with the valve inlet. The volume of the secondary fluid chamber can be selectively changed by translation of the secondary plunger rod. When the valve is closed, the secondary fluid chamber is isolated from the outlet lumen such that translation of the primary plunger rod draws fluid into or dispenses fluid out of the main chamber only via the outlet lumen. When the valve is open, the secondary fluid chamber is in fluid communication with the outlet lumen such that translation of the secondary plunger rod dispenses fluid out of the secondary chamber via the outlet lumen.

[0013] In some embodiments of the syringe disclosed herein, its secondary chamber is pre-filled with a flushing solution. Desirably, a clinician can administer a drug to a patient's VAD with the main chamber and immediately flush the VAD with the secondary chamber without removing the syringe from the VAD. In other embodiments of the syringe disclosed herein, a clinician can administer a drug through a VAD and immediately flush the VAD following a single, continuous advancement of both dual plungers.

[0014] Another aspect of the present disclosure relates to a syringe including a substantially cylindrical barrel that defines an inner wall. The barrel has an open proximal end and a distal end. The distal end of the barrel includes a connector that defines an outlet cavity therethrough. The outlet cavity is in fluid communication with the interior of the barrel; the interior is defined by the open proximal end, the distal end, and the inner wall. The syringe includes a main plunger having a tubular configuration that defines an inner surface and a through-hole orifice at its distal end. A secondary plunger is nested and captured within the inner surface of the tubular main plunger. The secondary plunger establishes fluid communication with the through-hole orifice of the main plunger and the outlet cavity. Nested main and secondary plunger rods that are selectively translatable within the barrel along a common axis are respectively coupled to the main and secondary plungers. A main stopper having a cup-shaped profile defines a radially projecting skirt that abuts the inner wall of the barrel. The main stopper is coupled to the distal end of the main plunger. The main stopper has a proximal surface facing the proximal end of the barrel and a distal surface facing the distal end of the barrel. The main stopper defines a through-hole between its proximal and distal surfaces that is in fluid communication with the through-hole orifice of the main plunger and the outlet cavity. A secondary stopper is coupled to the distal end of the secondary plunger. The secondary stopper has a distal surface facing the distal end of the barrel. A resealable check valve is disposed within the barrel, axially offset along the common axis toward the distal end of the barrel and away from the distal surface of the secondary stopper. The resealable valve has an inlet in fluid communication with the distal surface of the secondary stopper and an outlet in fluid communication with the through-hole of the main stopper, the through-hole orifice of the main plunger, and the outlet cavity. The syringe has a main fluid chamber within the barrel, defined between the distal surface of the main stopper and the distal end of the barrel, wherein the volume of the main fluid chamber can be selectively changed by translation of the main plunger rod. The syringe also has a secondary fluid chamber within the interior of the main plunger, between the distal surface of the secondary stopper and the valve inlet, the secondary fluid chamber being in fluid communication with the valve inlet. The volume of the secondary fluid chamber can be selectively changed by translation of the secondary plunger rod. When the valve is closed, the secondary fluid chamber is isolated from the outlet cavity such that translation of the main plunger rod draws fluid into or dispenses fluid from the main chamber only via the outlet cavity. When the valve is open, the secondary fluid chamber is in fluid communication with the outlet cavity such that translation of the secondary plunger rod dispenses fluid from the secondary chamber via the outlet cavity.

[0015] Another aspect of the present disclosure relates to a syringe comprising a substantially cylindrical barrel that defines an inner wall, wherein the barrel has an open proximal end and a distal end. The distal end of the barrel includes a connector that defines an outlet cavity therethrough, wherein the outlet cavity is in fluid communication with the interior of the barrel, the interior being defined by the open proximal end, the distal end, and the inner wall. The syringe includes a main plunger having a tubular configuration that defines an inner surface and a through-hole orifice at its distal end. A secondary plunger is nested and captured within the inner surface of the tubular main plunger. The secondary plunger establishes fluid communication with the through-hole orifice of the main plunger and the outlet cavity. The syringe also has nested main and secondary plunger rods that are selectively translatable along a common axis within the barrel interior and are respectively coupled to the main and secondary plungers. The syringe includes a main stopper having a proximal surface facing the proximal end of the barrel and a distal surface facing the distal end of the barrel. The main stopper defines a through-hole between its proximal and distal surfaces that is in fluid communication with the through-hole orifice of the main plunger and the outlet cavity. A secondary stopper is coupled to the distal end of the secondary plunger, wherein the secondary stopper has a distal surface facing the distal end of the barrel. Both the secondary plunger and the secondary stopper are captured within the inner surface of the tubular main plunger. An umbrella valve is coupled to the respective distal ends of the tubular main plunger and the main stopper. The umbrella valve defines a radially projecting skirt oriented in a relative relationship to the distal surface of the main stopper. The umbrella valve has a proximal surface facing the proximal end of the barrel and a distal surface facing the distal end of the barrel. The syringe has a main fluid chamber within the barrel interior that is defined between the respective distal surfaces of the main stopper and the umbrella valve and the distal end of the barrel. The volume of the main fluid chamber is selectively variable by translation of the main plunger rod. The syringe also has a secondary fluid chamber within the interior of the main plunger, between the distal surface of the secondary stopper and the proximal surface of the umbrella valve, and is in fluid communication with the through-hole of the main stopper and the through-hole orifice of the main plunger. The volume of the secondary fluid chamber is selectively variable by translation of the secondary plunger rod. When the umbrella valve is closed, the secondary fluid chamber is isolated from the outlet cavity such that translation of the main plunger rod draws fluid into or dispenses fluid from the main chamber only via the outlet cavity. When the umbrella valve is open, the secondary fluid chamber is in fluid communication with the outlet cavity such that translation of the secondary plunger rod draws fluid into or dispenses fluid from the secondary chamber via the outlet cavity.

[0016] The corresponding features of the aspects and exemplary embodiments of the present disclosure described herein may be applied jointly or separately in any combination or sub-combination. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Exemplary embodiments of the present disclosure are further described below in conjunction with the accompanying drawings, wherein:

[0018] Figure 1 is a cross-sectional view of an embodiment of a dual-chamber syringe having concentrically oriented main and secondary fluid chambers, each chamber containing fluid;

[0019] Figure 2 is a cross-sectional view of a one-way duckbill valve in a sealed or closed state;

[0020] Figure 3 is in an open state Figure 2 of the one-way duckbill valve;

[0021] Figures 4 - 7 is the illustrative sequential steps of using Figure 1 of the syringe, respectively showing the aspiration of fluid (e.g., drug) in the main chamber and its dispensing / infusion into an intravenous fluid catheter or port, and then flushing the catheter with the fluid in the secondary chamber;

[0022] Figure 8 is a cross-sectional view of another embodiment of a dual-chamber syringe including an externally actuated isolation valve, each chamber containing fluid;

[0023] Figure 9 is Figure 8 exploded view of the syringe;

[0024] Figure 10 and 11 is Figure 8 detailed cross-sectional view of the syringe, showing the needle valve in the closed and open positions, respectively;

[0025] Figure 12 is Figure 8 perspective view of the syringe, showing the cam slots for selectively engaging the needle valve in the closed and open positions of Figure 10 and 11 ;

[0026] Figure 13 is a cross-sectional view of another embodiment of a dual-chamber syringe, wherein the secondary chamber or proximal chamber is included within its main plunger and pre-filled with fluid;

[0027] Figure 14 is Figure 13 cross-sectional view of the syringe, wherein another fluid has been aspirated into its main chamber or distal chamber;

[0028] Figure 15 is Figure 13Cross-sectional view of a syringe in which fluid in the secondary or proximal chamber is being dispensed;

[0029] Figure 16 is Figure 13 Cross-sectional view of the syringe after all of the fluid in the secondary or proximal chamber has been dispensed;

[0030] Figure 17 Cross-sectional view of another embodiment of a dual-chamber syringe in which the secondary or proximal chamber is included within its main plunger.

[0031] For ease of understanding, where possible, the same reference numerals have been used to denote the same elements common to the figures. The figures are not drawn to scale. DETAILED DESCRIPTION

[0032] Aspects of the dual-chamber syringe embodiments disclosed herein facilitate selective drug mixing, metering, and administration via a catheter or other vascular access device (VAD), as well as pre- or post-administration flushing of the catheter with a single syringe instrument. Generally, in each disclosed embodiment, the syringe barrel includes an outlet, such as a Luer connector, that is selectively in fluid communication with a primary variable-volume fluid chamber and a secondary variable-volume fluid chamber. In some embodiments, the chamber pair has a tandem, in-line orientation within the syringe barrel, while in other embodiments, the chamber pair is nested in a generally concentric orientation. In either type of chamber orientation, for each chamber, the syringe includes a nested corresponding plunger, a plunger rod that is selectively translatable along a common axis within the barrel interior, and a plunger stopper. Thus, separate drugs or other fluids (e.g., flush solution) are selectively and independently dispensed by a clinician. A selectively resealable valve disposed within the barrel interior selectively isolates the secondary fluid chamber from the primary fluid chamber and the outlet of the syringe barrel from fluid communication. In some embodiments, the valve is selectively actuated to facilitate both aspiration into and dispensing from the secondary chamber. In other embodiments, the valve is a one-way valve, such as a duckbill valve, that prevents backflow into the secondary chamber.

[0033] The isolated secondary chamber configuration advantageously facilitates the use of pre-packaged drugs or flush solution in that chamber, whereby a clinician can aspirate and dispense a drug with an empty primary chamber and then immediately deliver the pre-packaged flush solution from the secondary chamber. In other embodiments, the syringes disclosed herein are used as drug mixing syringes, with a powdered drug pre-packaged in the primary chamber and a diluting solution pre-packaged in the secondary chamber. In some embodiments, a single forward stroke on the nested primary and secondary plungers of the syringe automatically delivers the drug contained in the primary chamber and then the flush solution sequentially into the VAD.

[0034] In the present disclosure, it follows such a convention that the distal end of a device is the end that is closest to the patient, e.g., for delivering one or more drugs to the patient, and the proximal end of the device is the end that is away from the patient and closest to the clinician or other medical practitioner. Regarding the terms used in the present disclosure, the following definitions are provided.

[0035] As used herein, the use of "a", "an", and "the" includes both singular and plural.

[0036] As used herein, the term "Luer connector" refers to a connecting collar that is a standard way of attaching syringes, catheters, needle with hub, IV tubes, etc. to each other. The Luer connector consists of male and female interlocking tubes that are slightly tapered so that they can be held together better even by just a simple press / twist fit. The Luer connector may optionally include an additional threaded outer rim to allow for greater security. The male end of the Luer connector is associated with a flush syringe and can interlock and connect with the female end located on a vascular access device (VAD). The Luer connector also has: a distal channel that releasably attaches the Luer connector to the seat of the VAD; and a proximal channel that releasably attaches the Luer connector to the barrel of the syringe.

[0037] As used herein, ISO 80369-7 defines the specifications of a standard Luer connector, including a 6% taper between the distal and proximal ends. The male standard Luer connector increases from the open distal end to the proximal end. The female standard Luer connector decreases from the open proximal end to the distal end. According to ISO 80369-7, the outer cross-sectional diameter of the male standard Luer connector measured at 0.75 millimeters from the distal end of the tip is between 3.970 millimeters and 4.072 millimeters. The length of the male standard Luer taper is between 7.500 millimeters and 10.500 millimeters. The outer cross-sectional diameter measured at 7.500 millimeters from the distal end of the tip is between 4.376 millimeters and 4.476 millimeters. As used herein, the phrases "male standard Luer connector" and "female standard Luer connector" shall refer to connectors having the dimensions described in ISO 80369-7, the entire content of ISO 80369-7 is hereby incorporated by reference herein.

[0038] As will be readily understood by those skilled in the relevant art, although descriptive terms such as "tip", "seat", "thread", "projection / insertion", "tab", "ramp", "wall", "top", "side", "bottom", etc. are used in this specification for ease of understanding, this is not intended to limit any components that can be combined or used alone or to require a specific spatial orientation for implementing various aspects of the embodiments of the present disclosure.

[0039] Before describing several exemplary embodiments of the present disclosure, it should be understood that the present disclosure is not limited to the details of the structures or process steps set forth in the following description. The present disclosure is capable of other embodiments and of being practiced or carried out in many ways.

[0040] The matters exemplified in this description are for helping to comprehensively understand the exemplary embodiments of the present disclosure. Therefore, those of ordinary skill in the art will recognize that various changes and modifications can be made to the embodiments described herein without departing from the scope and spirit of the present disclosure. Additionally, descriptions of well-known functions and structures are omitted for clarity and conciseness.

[0041] In an exemplary implementation of an embodiment of the present disclosure, the barrel of a syringe includes a distal end having a needleless connection portion. In one or more embodiments, the needleless connection portion includes all combinations of at least one thread and other features that allow it to interface with a corresponding one or more threads of a corresponding connector.

[0042] According to a further exemplary implementation of an embodiment of the present disclosure, the configuration of the structural element constituting the needleless connector includes a collar protruding from the distal end of the barrel, the collar including at least one thread for connection to a corresponding one or more threads of a corresponding connector.

[0043] According to a still further exemplary implementation of an embodiment of the present disclosure, the collar or the needleless connector can be bent or elastically deformed to allow for better interference fit compliance with the corresponding connector.

[0044] According to a still further exemplary implementation of an embodiment of the present disclosure, the needleless connector can include: a female thread sized and threaded to engage with a male fitting of the standard ISO 80369-7 type; and / or a male thread sized and threaded to engage with a female fitting of the standard ISO 80369-7 type. An example of an ISO 80369-7 type fitting is a Q-type fitting.

[0045] In one or more embodiments, the female connector may be selected from the group consisting essentially of: a needle-type connector (for direct injection into a patient or insertion into a vial to aspirate a drug dose therefrom), a needleless connector, a catheter Luer connector, a stopcock, and a hemodialysis connector. In one or more embodiments, the needleless connector is selected from Q-Syte connector, MaxPlus, MaxPlus Clear, MaxZero, UltraSite, Caresite, InVision-Plus, Safeline, OneLink, V-Link, ClearLink, NeutraClear, Clave, MicroClave, MicroClave Clear, Neutron, NanoClave, Kendall, Nexus, InVision, Vadsite, Bionector, and the like.

[0046] In one or more embodiments, the male connector may be an intravenous tube end or a stopcock.

[0047] Referring now to the drawings, in Figures 1 - 7 is shown a first aspect of the present disclosure, wherein syringe 20 has a concentrically oriented dual chamber. Syringe 20 includes a generally cylindrical outer barrel 22 that defines an inner wall 24, an open proximal end 26, an inwardly radially projecting plunger stop 27, and a distal end 28. The distal end 28 of outer barrel 22 includes a Luer connector 30 that defines an outlet chamber 32 for attachment to and fluid communication with various associated VAD connectors (schematically shown as connector 34). The interior 36 of outer barrel 22 is generally defined and bounded by its inner wall 24, its open proximal end 26, and its distal end 28. Syringe 20 has an inner barrel 38 nested within outer barrel 22 in a radially spaced relationship. Inner barrel 38 has an open proximal end 39 and a distal end 40 proximate distal end 28 of outer barrel 22. Inner barrel 38 has a corresponding inner wall 42 and outer wall 44. The interior 45 of inner barrel 38 is generally defined and bounded by its inner wall 42, its open proximal end 39, and its distal end 40.

[0048] Syringe 20 has a nested primary plunger 46 and secondary plunger 48 that respectively have a primary plunger rod 50 and a secondary plunger rod 52 that are selectively translatable along a common axis within interior 36 of outer barrel 22. As Figure 1 shown, primary plunger rod 50 has a tubular construction integral with primary plunger 46. Primary plunger 46 is nested within outer barrel 22 and surrounds inner barrel 38. Secondary plunger 48 is in turn nested within inner barrel 38 and primary plunger 46. Secondary plunger rod 52 is selectively attached to inner plunger head 54 of secondary plunger 48 by a screw 56, wherein the male threads of the screw engage mating female threads formed in secondary plunger rod.

[0049] The annular primary plug 58 is connected to the distal end of the primary plunger 46. The primary plug 58 has a proximal surface 60 facing the proximal end 26 of the outer barrel 22 and a distal surface 62 facing the distal end 28 of the outer barrel. The primary plug 58 is in fluid communication with the outlet chamber 32. The inner diameter 64 of the annular primary plug 58 is in fluid-tight contact with the outer side wall 44 of the inner barrel 38 and defines a through-hole between its proximal surface 60 and distal surface 62. The variable-volume annular primary chamber 66 (also referred to as the primary cavity) is in fluid communication with the outlet chamber 32 via a passage 67. However, when the primary plug 58 is fully pushed into the outer barrel 22, its distal surface 62 abuts a mating seating surface on the distal end 28 of the barrel, thereby isolating the primary chamber 66 from the passage 67 and the outlet chamber 32. The annular shape of the primary chamber 66 is defined within the boundaries of the distal surface 62 of the primary plug 58, the distal end 28 of the outer barrel 22, the inner side wall 24 of the outer barrel 22, and the outer side wall 44 of the inner barrel 38. The translation of the primary plunger rod 50 changes the volume of the primary chamber 66. The retraction or withdrawal of the primary plunger rod 50 sucks fluid from the outlet chamber 32 into the primary chamber 66. The retraction of the primary plunger rod 50 is limited by contact with an internal stop 27 formed in the outer barrel 22. Conversely, the insertion or advancement of the primary plunger rod 50 moves and expels fluid from the primary chamber 66 through the outlet chamber 32. Thus, a clinician can selectively suck a fluid such as a drug or a flushing solution into or expel it from the primary chamber 66 of the syringe 20.

[0050] The secondary plug 68 is coupled to the inner plunger head 54 at the distal end of the secondary plunger 48. An end cap 53 is coupled to the proximal open side of the inner barrel 38 to prevent the inner plunger head 54 and the secondary plug 68 from being accidentally removed from or separated within the inner barrel. The secondary plug has a distal surface 70 facing the distal end 40 of the inner barrel 38 and the distal end 28 of the outer barrel 22 and an outer peripheral surface 72 in fluid-tight contact with the inner side wall 42 of the inner barrel 38. The variable-volume secondary chamber 74 (also referred to as the secondary cavity) is defined within the boundaries of the distal surface 70 of the secondary plug 68 and the distal end 40 and the inner side wall 42 of the inner barrel 38. The translation of the secondary plunger rod 52 changes the volume of the secondary chamber 74. Thus, a clinician can selectively expel a fluid (such as a drug or a flushing solution) from the secondary chamber 74 by pushing the secondary plunger rod 52 into the syringe 20. In some embodiments, when the syringe 20 is pre-packaged with a fluid in the secondary chamber 74, the secondary plunger rod 52 is intentionally separated from the secondary plunger 48 to prevent inadvertent dosing. The clinician attaches the secondary plunger rod 52 before administering the pre-packaged dose to a patient.

[0051] Figures 1 - 7An embodiment of the syringe 20 includes a one-way valve 76 that is coupled to the distal end 40 of the inner barrel 38 for selectively isolating the secondary chamber 74 from the outlet chamber 32 of the Luer connector 30. When the syringe 20 is in use, a clinician can expel fluid from the secondary chamber 74 into the outlet chamber 32 by advancing the secondary plunger rod 52 into the inner barrel 38, but cannot aspirate fluid into the secondary chamber. Thus, the one-way valve 76 serves as a check valve. In Figure 2 and Figure 3 the physical structure and operation of the one-way valve 76 are schematically illustrated. The one-way valve 76 is a duckbill valve formed of a monolithic elastomer (e.g., medical grade silicone) having a conical or frustoconical profile. The inlet 78 of the duckbill valve 76 is coupled to the distal end 40 of the inner barrel 38, while its outlet 80 is oriented to face the Luer connector 30. As Figure 3 shown, when the pressure P1 in the Luer connector 30 is greater than or equal to the pressure P2 in the secondary chamber 74, the outlet 80 is in a sealed relaxed state. Conversely, in Figure 3 when the pressure P2 is greater than the pressure P1, such as when the secondary plunger 48 is advanced into the syringe 20, the elastomer in the valve 76 is radially stretched outward and deformed to expel fluid from the secondary chamber 74.

[0052] Figures 4 - 7 The functional operation of the syringe 20 is depicted by first retracting the main plunger 46 to aspirate a drug from a vial 84 into its main chamber 66 via the Luer connection 30 ( Figure 4 ). The drug is infused from the main chamber 66 into the previously flushed VAD 34 by advancing the main plunger 46, thereby emptying the main chamber ( Figure 5 ). If not previously secured to the syringe 20, the secondary plunger rod 52 is secured to its corresponding inner plunger head 54 ( Figure 6 ). The VAD 34 is flushed with a flush solution (e.g., saline or heparin) pre-packaged in the secondary chamber 74 by advancing the secondary plunger rod 52. Once the flushing procedure is complete, the syringe 20 is then withdrawn from the VAD 34.

[0053] In Figures 8 - 12Another aspect of the present disclosure is shown, where the dual-chamber syringe 90 has a primary chamber 92 and a secondary chamber 94 in series, axially aligned and oriented, with variable volumes. The secondary chamber 94 has a manually actuated selective isolation valve 96 that facilitates the inhalation of fluid into or the expulsion of fluid from its secondary chamber. In one or more embodiments, the primary chamber 92 is filled with a required amount of saline flush fluid. In one or more embodiments, the primary chamber 92 is filled with the required drug. In one or more embodiments, the secondary chamber 94 is filled with a required amount of saline flush fluid. In one or more embodiments, the secondary chamber 94 is filled with the required drug. In one or more embodiments, both the primary chamber 92 and the secondary chamber 94 are filled with the required drug. In one or more embodiments, both the primary chamber 92 and the secondary chamber 94 are filled with a required amount of saline flush fluid. The primary chamber 92 and / or the secondary chamber 94 are pre-filled with fluid using a sterile filling method during or after assembling the syringe 90. Additionally, the barrel 98 of the syringe 90 may include measurement markings 99 to indicate the amount of fluid contained therein.

[0054] The syringe 90 includes a substantially cylindrical barrel 98 that defines an inner wall 100. The barrel 98 has an open proximal end 102 and a distal end 104. The distal end 104 of the barrel 98 includes a Luer connector 106 that defines an exit chamber 108 therethrough. The exit chamber 108 is in fluid communication with the interior 110 of the barrel 98, where the interior is defined by the open proximal end 102, the distal end 104, and the inner wall 100.

[0055] The syringe 90 includes a nested primary plunger 112 and secondary plunger 114 that are disposed within the barrel interior 110 and have integral tubular primary and secondary plunger rods, respectively, that are selectively translatable along a common axis within the barrel interior. A threaded plunger nut 115 mates with an external thread formed on the distal end of the primary plunger 112, which also captures the secondary plunger 114 and holds the two plungers in a nested orientation.

[0056] A primary stopper 116 is coupled to the distal end of the primary plunger 112. The primary stopper 116 has a proximal surface 118 facing the open proximal end 102 of the barrel 98 and a distal surface 120 facing the distal end 104 of the barrel. The primary stopper 116 defines a through hole 122 between its proximal surface 118 and distal surface 120, and the through hole 122 is in fluid communication with the exit chamber 108. A secondary stopper 124 is coupled to the distal end of the secondary plunger 114. The secondary stopper has a distal surface 126 facing the distal end 104 of the barrel 98.

[0057] Reference Figures 10 - 12, the isolation valve 96 includes a spring-loaded shaft-mounted needle valve 128 disposed within the tubular main plunger 112 and a mating seat 130 formed within the through-hole 122 of the main plug. In some embodiments, the needle valve 128 and the seat 130 have a luer connector profile. The spring 132 biases the needle valve 128 away from the seat 130, holding the isolation valve in the open position; this allows fluid to flow from the secondary chamber 94 into the primary chamber 92 and the outlet 108. The main plunger 112 defines at least one cam groove 134 having an open engagement surface portion 136 and a closed engagement surface portion 138, within which a radially projecting cross pin 140 of the shaft of the needle valve 116 is constrained. The isolation valve 96 is closed by twisting and then pressing on the slotted knob 142 on the shaft of the needle valve 128 to disengage the open engagement surface 136 of the cam groove 134. This compresses the spring 132 and advances the needle valve 128 into mating contact with the corresponding seat 130, thereby closing the valve and isolating the secondary chamber 94 from the primary chamber 92 and the outlet 108 of the luer connector 106. The needle valve 128 is locked in its closed position by twisting the slotted knob 142 such that the cross pin 140 of the isolation valve 96 engages and is restricted within the closed engagement surface 138 of the cam groove 134. In some embodiments, the main plunger 112 has three cam grooves 134, and there are three corresponding cross pins 140 on the isolation valve 96. An annular shaft seal 144 prevents fluid leakage between the elongated stem of the isolation valve 96 and the main plunger 112. The main plunger 112 and the shaft of the needle valve 128 are sized to inhibit buckling of the shaft and maintain vertical alignment of the needle valve tip and its mating seat 130.

[0058] When the syringe 90 is used, the secondary chamber 94 is pre-filled with fluid, with the isolation valve 96 in the closed position to prevent leakage of the fluid. Alternatively, the secondary chamber 94 is filled on-site at the treatment center. If the latter, before filling the syringe 90, the isolation valve 96 is opened; both the primary stopper 116 and the secondary stopper 124 are fully advanced together with the primary plunger 112 and the secondary plunger 114 such that the distal surface 120 of the primary stopper 116 abuts the distal end 104 of the barrel 98, and the distal surface 126 of the secondary stopper 124 abuts the proximal surface 118 of the primary stopper. Now, both the primary chamber 92 and the secondary chamber 94 have been compressed to a zero-volume state. To aspirate and fill the empty secondary chamber 94, the secondary plunger 114 is retracted while the primary plunger remains in its fully advanced position. The plunger stop 146 projects radially into the interior of the barrel 98 to prevent unintentional separation of the primary plunger 112 and the secondary plunger 114 from the barrel. When the secondary chamber 94 is filled to the desired capacity, the isolation valve 96 is closed, thereby isolating its contents. Thereafter, the primary chamber 92 is aspirated by retracting the primary plunger 112. In some applications, the syringe 90 is used to reconstitute a powdered drug that has been pre-filled in the primary chamber 92 by dispersing a pre-filled diluent liquid stored in the secondary chamber 94 into the primary chamber. In other applications, the primary chamber 92 is used to aspirate a drug and dispense it into a VAD, and after opening the isolation valve 96, the VAD is subsequently flushed with a flush solution stored in the secondary chamber 94.

[0059] In Figures 13 - 16 Another aspect of the present disclosure is shown, where the dual-chamber syringe 150 has a primary chamber 152 and a secondary chamber 154 of variable volume that are in series, axially aligned and oriented. The secondary chamber 154 is included within the primary plunger 172. A one-way duckbill valve 156 facilitates the discharge of fluid from its secondary chamber 154. The duckbill valve 156 has a construction and operation similar to that of Figure 2 and Figure 3 the duckbill valve 76; it does not allow fluid to flow back or reverse flow into the secondary chamber 154. As with the previously described syringe embodiments, in one or more embodiments of the syringe 150, the primary chamber 152 and / or the secondary chamber 154 are pre-filled with one or more fluids, such as a flush fluid or a drug.

[0060] The syringe 150 includes a substantially cylindrical barrel 158 that defines an inner wall 160. The barrel 158 has an open proximal end 162 and a distal end 164. The distal end 164 of the barrel 158 includes a Luer connector 166 that defines an exit chamber 168 therethrough. The exit chamber 168 is in fluid communication with the interior 170 of the barrel 158, where the interior is defined by the open proximal end 162, the distal end 164, and the inner wall 160.

[0061] The syringe 150 includes a nested primary plunger 172 and a secondary plunger 174 disposed within the barrel interior 170 and having integral primary and secondary plunger rods that are selectively translatable within the barrel interior 170 along a common axis. The primary plunger 172 has a hollow tubular configuration and includes the structure of the secondary chamber 154. Thus, when the primary plunger 172 is advanced or retracted within the barrel interior 170, the secondary chamber 154 translates with the primary plunger 172. Additionally, the outer surface of the barrel 158 and / or the secondary plunger 174 may include measurement markings to indicate the amount of fluid contained therein.

[0062] Reference Figure 13 and Figure 16 , a primary stopper 176 is coupled to the distal end of the primary plunger 172. The primary stopper 176 has a proximal surface 178 facing the open proximal end 162 of the barrel 158 and a distal surface 180 facing the distal end 164 of the barrel. The primary stopper 176 defines a through-hole 182 between its proximal surface 178 and distal surface 180, where the hole is in fluid communication with the outlet chamber 168. A secondary stopper 184 is coupled to the distal end of the secondary plunger 174. The secondary stopper has a distal surface 186 facing the distal end 164 of the barrel 158 and a circumferential sealing skirt 188. The circumferential sealing skirt 188 makes a frictionally tight fluid-sealing contact with the inner sidewall 190 of the primary plunger 172.

[0063] A variable-volume primary chamber 152 is defined within the boundaries of the distal surface 180 of the primary stopper 176, the distal end 164 and inner sidewall 160 of the barrel 158, and the distal surface 186 of the secondary stopper 184. A variable-volume secondary chamber 154 is defined within the boundaries of the distal surface 186 of the secondary stopper 184, the distal end 194 and inner sidewall 190 of the tubular primary plunger 172, and the distal surface 186 of the secondary stopper 184. In operation, as Figures 13 - 16 shown, by retracting the secondary plunger 174 ( Figure 14 ), the empty primary chamber 152 is aspirated and filled with the desired fluid. The frictional contact between the circumferential sealing skirt 188 of the secondary stopper 184 and the opposing abutting inner sidewall 190 of the primary plunger 172 causes the primary plunger and its primary stopper 176 to translate towards the proximal opening end 162 of the barrel 158. To prevent the primary plunger 172 and the nested secondary plunger 174 from accidentally separating from the barrel 158, the retraction of the two plungers is limited and stopped when the proximal surface 194 of the primary plunger contacts an internal stop ring 196 inserted into the open proximal end 162 of the barrel 158. In Figure 15In [the syringe], the fluid in the main chamber 154 has been expelled by advancing the secondary plunger 172 with sufficient force to advance the main plug 176 into contact with the distal end 164 of the barrel 158, but limiting the advancing force to a level below that required to open the duckbill valve 156. When it is desired to expel the contents of the secondary chamber 154, the secondary plunger 174 is advanced with sufficient force to open the duckbill valve 156, as previously explained with respect to the expulsion of the secondary chamber 74 of syringe 20 (see Figure 4 ). Thus, for the embodiment of syringe 158, by continuously advancing the secondary plunger 174 with sufficient force to open the duckbill valve 156, the clinician can automatically and sequentially deliver a drug with the main chamber 154 and then deliver a flush solution with the secondary chamber 154 without changing syringes.

[0064] In Figure 17 Another aspect of the present disclosure is shown, where the dual-chamber syringe 200 has a main chamber 202 and a secondary chamber 204 of variable volume that are in series, axially aligned and oriented, and formed in nested respective main barrel 206 and secondary barrel 208. A one-way umbrella valve 210 and a mating umbrella valve seat 212 are coupled to the secondary barrel 208; they serve as the main plug and facilitate storage of fluid in and expulsion from the secondary chamber 204. The umbrella valve seat 212 defines a through-hole 213. The umbrella valve 210 is oriented within the through-hole 213, preventing fluid from flowing from the main chamber 202 to the secondary chamber 204, which isolates the contents of the secondary chamber from the remainder of the syringe 200. As with the syringe embodiments described previously, in one or more embodiments of syringe 200, the main chamber 202 and / or the secondary chamber 204 are pre-filled with one or more fluids, such as a flush fluid or a drug.

[0065] The substantially cylindrical main barrel 206 defines an inner sidewall 214, an open proximal end 216, and a distal end 218. The distal end 218 of the main barrel 206 includes a Luer connector 220 that defines an outlet chamber 222 therethrough. The outlet chamber 222 is in fluid communication with the interior 224 of the main barrel 206, where the interior is defined by the open proximal end 216, the distal end 218, and the inner sidewall 214. The variable volume main chamber 202 is defined within the inner sidewall 214, and the distal end 218 of the main barrel 208 and the main plug including the umbrella valve 210 / umbrella valve seat 212.

[0066] The syringe 200 includes a nested pair of primary and secondary pistons that are selectively translatable along a common axis within the interior 224 of the primary barrel 206. The secondary barrel 208 serves as an integrated primary piston / integral piston rod disposed within the interior 224 of the primary barrel. Thus, the entire secondary chamber 204 translates with the secondary barrel because the secondary barrel serves as the primary piston to change the volume of the primary chamber 202 within the primary barrel 206. A retaining ring 228 adjacent the open proximal end 216 of the primary barrel 206 limits retraction of the integrated secondary barrel / primary piston 208 to prevent accidental separation of the secondary barrel from the syringe 200. The secondary piston 226 includes an integral piston rod that is selectively translatable within the respective interiors of the primary barrel 206 and the secondary barrel 208. Additionally, the outer surfaces of the primary barrel 206 and / or the barrel 208 and / or the secondary piston 226 may include measurement markings to indicate the amount of fluid contained therein.

[0067] A secondary stopper 230 is coupled to the distal end of the secondary piston 226. The secondary stopper has a distal surface 232 facing the distal end 218 of the primary barrel 208. A variable volume secondary chamber 204 is defined within the boundaries of the distal surface 232 of the secondary stopper 230, the inner sidewall 234 of the secondary barrel 208, and the umbrella valve seat 212. When in the locked state, a twist lock mechanism selectively locks the secondary piston 226 relative to the secondary piston barrel 208 in its maximum retracted position such that a pushing pressure on the secondary piston translates only the secondary barrel 208 to selectively change the volume of the primary chamber 202. The twist lock mechanism includes a pair of opposing radially projecting lugs 336 formed on the secondary piston 226 and mating corresponding lug recesses 240 formed within the inner sidewall 234 of the secondary piston barrel 208. When the twist lock mechanism is in the unlocked state, the lugs 336 of the secondary piston 226 are not engaged within the mating lug recesses 240 of the secondary barrel 208, thereby allowing the secondary piston and its attached secondary stopper 230 to translate within the secondary barrel.

[0068] The secondary chamber 204 of the syringe 200 is advantageously pre-filled with a desired fluid, such as water. In some embodiments, the primary chamber 202 is pre-filled with a dry powder drug, which is then mixed with the diluting fluid from the secondary chamber 204 by unlocking the locking mechanism and advancing the secondary plunger 226. The mixed drug is infused into the VAD by locking the secondary plunger 226 with the locking mechanism and advancing it together with the integrated secondary barrel 208 / primary plunger. In other embodiments, a secondary chamber 204 of the syringe 200 pre-filled with a flush solution and an empty primary chamber 202 are provided. The primary chamber 202 is selectively aspirated with a desired fluid, such as a drug, and discharged into the VAD. Subsequently, the VAD is flushed with the flush solution in the secondary chamber 204 using the same syringe 200. Thus, for embodiments of the syringe 200, a clinician can automatically and sequentially deliver a drug to the VAD and then flush the VAD by: (i) advancing the secondary plunger 226 while in the locked state, thereby discharging the drug-filled primary chamber 202 into the VAD, (ii) unlocking the secondary plunger with a simple twisting motion, and (iii) pressing the unlocked secondary plunger to discharge the flush solution-filled secondary chamber 204 into the VAD, all without the need to replace the syringe.

[0069] The syringe embodiments disclosed herein are constructed of medical grade materials known to those skilled in the art. In some embodiments, the described barrel, plunger, and shaft are made of polypropylene polymer. The seal is made of a polytetrafluoroethylene (PTFE) polymer filled with fibers. The stopper is made of polyisoprene polymer. The spring is made of stainless steel.

[0070] Embodiments

[0071] Example (a): A syringe comprising: a substantially cylindrical barrel defining an inner wall, the barrel having an open proximal end and a distal end, the distal end of the barrel including a connector defining an outlet cavity therethrough, the outlet cavity being in fluid communication with the interior of the barrel, the interior being defined by the open proximal end, the distal end and the inner wall; nested primary and secondary plungers disposed within the barrel, the primary and secondary plungers having primary and secondary plunger rods respectively capable of being selectively translated within the barrel along a common axis; a primary stopper coupled to the distal end of the primary plunger, the primary stopper having a proximal surface facing the proximal end of the barrel and a distal surface facing the distal end of the barrel, the primary stopper defining a through hole between its proximal and distal surfaces, the through hole being in fluid communication with the outlet cavity; a secondary stopper coupled to the distal end of the secondary plunger, the secondary stopper having a distal surface facing the distal end of the barrel; a resealable valve disposed within the barrel, axially offset along the common axis towards the distal end of the barrel and away from the distal surface of the secondary stopper, the resealable valve having an inlet in fluid communication with the distal surface of the secondary stopper and an outlet in fluid communication with the through hole of the primary stopper and the outlet cavity; a main fluid chamber within the barrel, defined between the distal surface of the primary stopper and the distal end of the barrel, the volume of the main fluid chamber being capable of being selectively changed by translation of the primary plunger rod; a secondary fluid chamber within the barrel, defined between the distal surface of the secondary stopper and the inlet of the valve, in fluid communication with the inlet of the valve, the volume of the secondary fluid chamber being capable of being selectively changed by translation of the secondary plunger rod; wherein when the valve is closed, the secondary fluid chamber is isolated from the outlet cavity such that translation of the primary plunger rod draws fluid into or dispenses fluid from the main fluid chamber only via the outlet cavity; and wherein when the valve is open, the secondary fluid chamber is in fluid communication with the outlet cavity such that translation of the secondary plunger rod dispenses fluid from the secondary fluid chamber via the outlet cavity.

[0072] Example (b): The syringe according to Example (a), further comprising: a tubular primary plunger, the inner surface of the tubular primary plunger defining the secondary fluid chamber and a through hole orifice at the distal end of the tubular primary plunger for establishing fluid communication with the through hole of the primary stopper and the outlet cavity; the primary stopper having a cup-shaped profile defining a radially projecting skirt in abutting contact with the inner wall of the barrel; the valve outlet being coupled to the through hole orifice of the tubular primary plunger; and the secondary plunger and secondary stopper being captured within the inner surface of the tubular primary plunger.

[0073] Example (c): The syringe according to example (a), wherein the valve comprises a duckbill valve.

[0074] Example (d): The syringe according to example (a), further comprising an inner surface of the distal end of the barrel, which defines a seating surface for abutting engagement with the distal surface of the main plunger when the main plunger is fully advanced within the barrel, thereby isolating the main fluid chamber from the outlet chamber and the outlet of the valve.

[0075] Example (e): The syringe according to example (a), further comprising an inner surface of the distal end of the secondary fluid chamber, which defines a seating surface for abutting engagement with the distal surface of the secondary plunger when the secondary plunger is fully advanced within the barrel, thereby isolating the secondary fluid chamber from the outlet chamber and the outlet of the valve.

[0076] Example (f): The syringe according to example (a), further comprising: a tubular main plunger, the inner surface of the tubular main plunger defining the secondary fluid chamber and a through-hole orifice at the distal end of the tubular main plunger, the through-hole orifice for establishing fluid communication with the through-hole of the main plunger and the outlet chamber; an umbrella-valve type resealable valve, the umbrella-valve type resealable valve being included within the main plunger and defining a radially projecting skirt coupled to the distal end of the tubular main plunger; and the secondary plunger and secondary stopper being captured within the inner surface of the tubular main plunger.

[0077] Example (g): The syringe according to example (f), wherein the secondary plunger rod has a locking mechanism, the locking mechanism having a locking engagement position with the main plunger to prevent accidental advancement of the secondary plunger and an unlocking engagement position to allow advancement of the secondary plunger and distribution of fluid from the secondary fluid chamber to the outlet chamber.

[0078] Example (h): The syringe according to example (g), wherein the locking mechanism comprises a twist-lock mechanism.

[0079] Example (i): A syringe comprising: a substantially cylindrical barrel defining an inner wall, the barrel having an open proximal end and a distal end, the distal end of the barrel including a connector defining an outlet cavity therethrough, the outlet cavity being in fluid communication with the interior of the barrel, the interior being defined by the open proximal end, the distal end and the inner wall; a main plunger having a tubular configuration defining an inner surface and a through-hole orifice at its distal end; a secondary plunger nested and captured within the inner surface of the tubular main plunger, the secondary plunger establishing fluid communication with the through-hole orifice of the main plunger and the outlet cavity; nested main and secondary plunger rods capable of selective translation along a common axis within the barrel, respectively coupled to the main and secondary plungers; a main stopper having a cup-shaped profile defining a radially projecting skirt in abutting contact with the inner wall of the barrel, the main stopper being coupled to the distal end of the main plunger, the main stopper having a proximal surface facing the proximal end of the barrel and a distal surface facing the distal end of the barrel, the main stopper defining a through-hole between its proximal and distal surfaces, the through-hole being in fluid communication with the through-hole orifice of the main plunger and the outlet cavity; a secondary stopper coupled to the distal end of the secondary plunger, the secondary stopper having a distal surface facing the distal end of the barrel; a resealable one-way valve disposed within the barrel, axially offset along the common axis towards the distal end of the barrel and away from the distal surface of the secondary stopper, the resealable one-way valve having an inlet in fluid communication with the distal surface of the secondary stopper and an outlet in fluid communication with the through-hole of the main stopper, the through-hole orifice of the main plunger and the outlet cavity; a main fluid chamber within the barrel, defined between the distal surface of the main stopper and the distal end of the barrel, the volume of the main fluid chamber being selectively variable by translation of the main plunger rod; a secondary fluid chamber within the interior of the main plunger, between the distal surface of the secondary stopper and the inlet of the valve, in fluid communication with the inlet of the valve, the volume of the secondary fluid chamber being selectively variable by translation of the secondary plunger rod; wherein when the valve is closed, the secondary fluid chamber is isolated from the outlet cavity such that translation of the main plunger rod draws fluid into or dispenses fluid out of the main fluid chamber only via the outlet cavity; and wherein when the valve is open, the secondary fluid chamber is in fluid communication with the outlet cavity such that translation of the secondary plunger rod dispenses fluid out of the secondary fluid chamber via the outlet cavity.

[0080] Example (j): The syringe according to example (i) further comprises mating convex and concave engaging surfaces that are radially oriented with respect to the common axis, one of the convex and concave engaging surfaces being formed on the inner surface of the tubular main plunger and the other of the convex and concave engaging surfaces being formed on the secondary plunger for preventing the secondary plunger from separating from the barrel.

[0081] Example (k): The syringe according to example (j), wherein the valve comprises a duckbill valve.

[0082] Example (l): The syringe according to example (j) further comprises the inner surface of the distal end of the barrel that defines a seating surface for abutting engagement with the distal surface of the main plug when the main plug is fully advanced within the barrel, thereby isolating the main fluid chamber from the outlet chamber and the outlet of the valve.

[0083] Example (m): The syringe according to example (j) further comprises the inner surface of the distal end of the secondary fluid chamber that defines a seating surface for abutting engagement with the distal surface of the secondary plug when the secondary plug is fully advanced within the barrel, thereby isolating the secondary fluid chamber from the outlet chamber and the outlet of the valve.

[0084] Example (n): The syringe according to example (i), wherein the valve comprises a duckbill valve.

[0085] Example (o): The syringe according to example (i) further comprises the inner surface of the distal end of the barrel that defines a seating surface for abutting engagement with the distal surface of the main plug when the main plug is fully advanced within the barrel, thereby isolating the main fluid chamber from the outlet chamber and the outlet of the valve.

[0086] Example (p): The syringe according to example (i) further comprises the inner surface of the distal end of the secondary fluid chamber that defines a seating surface for abutting engagement with the distal surface of the secondary plug when the secondary plug is fully advanced within the barrel, thereby isolating the secondary fluid chamber from the outlet chamber and the outlet of the valve.

[0087] Example (q): A syringe comprising: a substantially cylindrical barrel defining an inner wall, the barrel having an open proximal end and a distal end, the distal end of the barrel including a connector defining an outlet cavity therethrough, the outlet cavity being in fluid communication with the interior of the barrel, the interior being defined by the open proximal end, the distal end, and the inner wall; a main plunger having a tubular configuration defining an inner surface and a through-hole orifice at its distal end; a secondary plunger nested and captured within the inner surface of the tubular main plunger, the secondary plunger establishing fluid communication with the through-hole orifice of the main plunger and the outlet cavity; nested main and secondary plunger rods capable of selective translation along a common axis within the barrel, respectively coupled to the main and secondary plungers; a main stopper having a proximal surface facing the proximal end of the barrel and a distal surface facing the distal end of the barrel, the main stopper defining a through-hole between its proximal and distal surfaces, the through-hole being in fluid communication with the through-hole orifice of the main plunger and the outlet cavity; a secondary stopper coupled to the distal end of the secondary plunger, the secondary stopper having a distal surface facing the distal end of the barrel, the secondary plunger and secondary stopper being captured within the inner surface of the tubular main plunger; an umbrella valve coupled to the respective distal ends of the tubular main plunger and the main stopper, the umbrella valve defining a radially projecting skirt oriented in a relative relationship to the distal surface of the main stopper, and the umbrella valve having a proximal surface facing the proximal end of the barrel and a distal surface facing the distal end of the barrel; a main fluid chamber within the barrel, defined between the respective distal surfaces of the main stopper and the umbrella valve and the distal end of the barrel, the volume of the main fluid chamber being selectively variable by translation of the main plunger rod; a secondary fluid chamber within the interior of the main plunger, between the distal surface of the secondary stopper and the proximal surface of the umbrella valve, in fluid communication with the through-hole of the main stopper and the through-hole orifice of the main plunger, the volume of the secondary fluid chamber being selectively variable by translation of the secondary plunger rod; wherein when the umbrella valve is closed, the secondary fluid chamber is isolated from the outlet cavity such that translation of the main plunger rod draws fluid into or dispenses fluid out of the main fluid chamber only via the outlet cavity; and wherein when the umbrella valve is open, the secondary fluid chamber is in fluid communication with the outlet cavity such that translation of the secondary plunger rod dispenses fluid out of the secondary fluid chamber via the outlet cavity.

[0088] Example (r): The syringe according to Example (q), wherein the secondary plunger rod has a locking mechanism, the locking mechanism having a locking engagement position with the primary plunger to prevent accidental advancement of the secondary plunger and an unlocking engagement position to allow advancement of the secondary plunger and distribution of fluid from the secondary fluid chamber to the outlet chamber.

[0089] Example (s): The syringe according to Example (r), wherein the locking mechanism includes a twist-lock mechanism.

[0090] Throughout this specification, references to "one embodiment", "certain embodiments", "various embodiments", "one or more embodiments", or "an embodiment" mean that a particular feature, structure, material, or characteristic described in connection with the embodiment is included in at least one embodiment of the present disclosure. Thus, the appearances of the phrases such as "in one or more embodiments", "in certain embodiments", "in various embodiments", "in one embodiment", or "in an embodiment" throughout this specification are not necessarily referring to the same embodiment of the present disclosure. Moreover, in one or more embodiments, the particular features, structures, materials, or characteristics may be combined in any suitable manner. Additionally, it should be understood that the terminology and phrases used herein are for the purpose of description and should not be regarded as limiting. As used herein, the terms "comprising", "including", or "having" and their variants are intended to cover the items listed thereafter and their equivalents as well as additional items. Unless otherwise specified or limited, the terms "mounted", "connected", "supported", and "coupled" and their variants are interpreted broadly; they cover direct and indirect mounting, connection, support, and coupling. Additionally, "connected" and "coupled" are not limited to physical, mechanical, or electrical connection or coupling.

[0091] Although the present disclosure provides a description with reference to exemplary embodiments, it should be understood that these embodiments are merely illustrative of the principles and applications of the present disclosure. It will be apparent to those skilled in the art that various modifications and variations can be made to the present disclosure without departing from the spirit and scope of the present disclosure. Accordingly, the present disclosure is intended to cover modifications and variations that fall within the scope of the appended claims and their equivalents. The appended claims are not limited to the details of the exemplary embodiments of the construction and arrangement of components set forth in the specification or shown in the drawings.

Claims

1. A syringe, comprising: a substantially cylindrical barrel that defines an inner wall, the barrel having an open proximal end, and a distal end, the distal end of the barrel including a connector that defines an outlet cavity therethrough, the outlet cavity being in fluid communication with the interior of the barrel, the interior being defined by the open proximal end, the distal end, and the inner wall; a nested primary plunger and secondary plunger, the primary plunger and secondary plunger being disposed within the barrel and having a primary plunger rod and a secondary plunger rod, respectively, that are selectively translatable within the barrel along a common axis; a primary stopper that is coupled to the distal end of the primary plunger, the primary stopper having a proximal surface facing the proximal end of the barrel and a distal surface facing the distal end of the barrel, the primary stopper defining a through hole between its proximal surface and distal surface, the through hole being in fluid communication with the outlet cavity; a secondary stopper that is coupled to the distal end of the secondary plunger, the secondary stopper having a distal surface facing the distal end of the barrel; a resealable valve that is disposed within the barrel and is axially offset along the common axis toward the distal end of the barrel and away from the distal surface of the secondary stopper, the resealable valve having an inlet in fluid communication with the distal surface of the secondary stopper and an outlet in fluid communication with the through hole of the primary stopper and the outlet cavity; a main fluid chamber that is within the barrel and is defined between the distal surface of the primary stopper and the distal end of the barrel, the volume of the main fluid chamber being selectively variable by translation of the primary plunger rod; a secondary fluid chamber that is within the barrel and is defined between the distal surface of the secondary stopper and the inlet of the valve, being in fluid communication with the inlet of the valve, the volume of the secondary fluid chamber being selectively variable by translation of the secondary plunger rod; wherein when the valve is closed, the secondary fluid chamber is isolated from the outlet cavity such that translation of the primary plunger rod draws fluid into the main fluid chamber or dispenses fluid out of the main fluid chamber only via the outlet cavity; and wherein when the valve is open, the secondary fluid chamber is in fluid communication with the outlet cavity such that translation of the secondary plunger rod dispenses fluid out of the secondary fluid chamber via the outlet cavity.

2. The syringe according to claim 1, further comprising: a tubular primary plunger, the inner surface of the tubular primary plunger defining the secondary fluid chamber and a through hole orifice at the distal end of the tubular primary plunger for establishing fluid communication with the through hole of the primary stopper and the outlet cavity; the primary stopper having a cup-shaped profile defining a radially projecting skirt that abuts against the inner wall of the barrel; the valve outlet being coupled to the through hole orifice of the tubular primary plunger; and the secondary plunger and secondary stopper being captured within the inner surface of the tubular primary plunger.

3. The syringe according to claim 1, wherein the valve comprises a duckbill valve.

4. The syringe according to claim 1 further includes an inner surface of the distal end of the barrel, which defines a seating surface for abutting engagement with the distal surface of the main plunger when the main plunger is fully advanced within the barrel, thereby isolating the main fluid chamber from the outlet chamber and the outlet of the valve.

5. The syringe according to claim 1 further includes an inner surface of the distal end of the secondary fluid chamber, which defines a seating surface for abutting engagement with the distal surface of the secondary plunger when the secondary plunger is fully advanced within the barrel, thereby isolating the secondary fluid chamber from the outlet chamber and the outlet of the valve.

6. The syringe according to claim 1 further includes: a tubular main plunger, the inner surface of the tubular main plunger defining the secondary fluid chamber and a through-hole orifice at the distal end of the tubular main plunger, the through-hole orifice for establishing fluid communication with the through-hole of the main plunger and the outlet chamber; an umbrella-valve type resealable valve, the umbrella-valve type resealable valve being included within the main plunger and defining a radially projecting skirt coupled to the distal end of the tubular main plunger; and the secondary plunger and secondary plunger are captured within the inner surface of the tubular main plunger.

7. In the syringe according to claim 6, the secondary plunger rod has a locking mechanism, the locking mechanism having a locking engagement position with the main plunger to prevent accidental advancement of the secondary plunger and an unlocking engagement position to allow advancement of the secondary plunger and dispense fluid from the secondary fluid chamber into the outlet chamber.

8. In the syringe according to claim 7, the locking mechanism includes a twist-lock mechanism.

9. A syringe comprising: a substantially cylindrical barrel, the barrel defining an inner sidewall, the barrel having an open proximal end and a distal end, the distal end of the barrel including a connector, the connector defining an outlet chamber therethrough, the outlet chamber being in fluid communication with the interior of the barrel, the interior being defined by the open proximal end, the distal end, and the inner sidewall; a main plunger, the main plunger having a tubular configuration, defining an inner surface and a through-hole orifice at its distal end; a secondary plunger, the secondary plunger being nested and captured within the inner surface of the tubular main plunger, the secondary plunger establishing fluid communication with the through-hole orifice of the main plunger and the outlet chamber; nested main and secondary plunger rods, the main and secondary plunger rods being selectively translatable along a common axis within the interior of the barrel and coupled to the main and secondary plungers, respectively; a main stopper, the main stopper having a cup-shaped profile, defining a radially projecting skirt in abutting contact with the inner sidewall of the barrel, the main stopper being coupled to the distal end of the main plunger, the main stopper having a proximal surface facing the proximal end of the barrel and a distal surface facing the distal end of the barrel, the main stopper defining a through-hole between its proximal and distal surfaces, the through-hole being in fluid communication with the through-hole orifice of the main plunger and the outlet chamber; A secondary plug, the secondary plug being coupled to the distal end of the secondary plunger, the secondary plug having a distal surface facing the distal end of the barrel; A resealable check valve, the resealable check valve being disposed within the barrel interior, axially offset along the common axis toward the distal end of the barrel and away from the distal surface of the secondary plug, the resealable check valve having an inlet in fluid communication with the distal surface of the secondary plug and an outlet in fluid communication with the through-hole of the primary plug, the through-hole orifice of the primary plunger, and the outlet chamber; A main fluid chamber, the main fluid chamber being within the barrel interior, defined between the distal surface of the primary plug and the distal end of the barrel, the volume of the main fluid chamber being selectively variable by translation of the primary plunger rod; A secondary fluid chamber, the secondary fluid chamber being within the interior of the primary plunger, between the distal surface of the secondary plug and the inlet of the valve, in fluid communication with the inlet of the valve, the volume of the secondary fluid chamber being selectively variable by translation of the secondary plunger rod; wherein, when the valve is closed, the secondary fluid chamber is isolated from the outlet chamber such that translation of the primary plunger rod draws fluid into or dispenses fluid from the main fluid chamber only via the outlet chamber; and wherein, when the valve is open, the secondary fluid chamber is in fluid communication with the outlet chamber such that translation of the secondary plunger rod dispenses fluid from the secondary fluid chamber via the outlet chamber.

10. The syringe according to claim 9, further comprising mating convex and concave engagement surfaces oriented radially with respect to the common axis, one of the convex and concave engagement surfaces being formed on the inner surface of the tubular primary plunger and the other of the convex and concave engagement surfaces being formed on the secondary plunger for preventing separation of the secondary plunger from the barrel.

11. The syringe according to claim 10, wherein the valve comprises a duckbill valve.

12. The syringe according to claim 10, further comprising an inner surface of the distal end of the barrel defining a seating surface for abutting engagement with the distal surface of the primary plug when the primary plug is fully advanced within the barrel, thereby isolating the main fluid chamber from the outlet chamber and the outlet of the valve.

13. The syringe according to claim 10, further comprising an inner surface of the distal end of the secondary fluid chamber defining a seating surface for abutting engagement with the distal surface of the secondary plug when the secondary plug is fully advanced within the barrel, thereby isolating the secondary fluid chamber from the outlet chamber and the outlet of the valve.

14. The syringe according to claim 9, wherein the valve comprises a duckbill valve.

15. The syringe according to claim 9 further includes an inner surface of the distal end of the barrel, which defines a seating surface for abutting engagement with the distal surface of the main plunger when the main plunger is fully advanced within the barrel, thereby isolating the main fluid chamber from the outlet chamber and the outlet of the valve.

16. The syringe according to claim 9 further includes an inner surface of the distal end of the secondary fluid chamber, which defines a seating surface for abutting engagement with the distal surface of the secondary plunger when the secondary plunger is fully advanced within the barrel, thereby isolating the secondary fluid chamber from the outlet chamber and the outlet of the valve.

17. A syringe comprising: A substantially cylindrical barrel defining an inner sidewall, the barrel having an open proximal end and a distal end, the distal end of the barrel including a connector defining an outlet chamber therethrough, the outlet chamber being in fluid communication with the interior of the barrel, the interior being defined by the open proximal end, the distal end, and the inner sidewall; A main plunger having a tubular configuration defining an inner surface and a through-hole orifice at its distal end; A secondary plunger nested and captured within the inner surface of the tubular main plunger, the secondary plunger establishing fluid communication with the through-hole orifice of the main plunger and the outlet chamber; Nested main and secondary plunger rods capable of selective translation along a common axis within the barrel interior and respectively coupled to the main and secondary plungers; A main stopper having a proximal surface facing the proximal end of the barrel and a distal surface facing the distal end of the barrel, the main stopper defining a through-hole between its proximal and distal surfaces, the through-hole being in fluid communication with the through-hole orifice of the main plunger and the outlet chamber; A secondary stopper coupled to the distal end of the secondary plunger, the secondary stopper having a distal surface facing the distal end of the barrel, the secondary plunger and secondary stopper being captured within the inner surface of the tubular main plunger; An umbrella valve coupled to the respective distal ends of the tubular main plunger and the main stopper, the umbrella valve defining a radially projecting skirt oriented in a relative relationship with the distal surface of the main stopper, and the umbrella valve having a proximal surface facing the proximal end of the barrel and a distal surface facing the distal end of the barrel; A main fluid chamber within the barrel interior, defined between the respective distal surfaces of the main stopper and the umbrella valve and the distal end of the barrel, the volume of the main fluid chamber being selectively variable by translation of the main plunger rod; A secondary fluid chamber within the interior of the main plunger, between the distal surface of the secondary stopper and the proximal surface of the umbrella valve, in fluid communication with the through-hole of the main stopper and the through-hole orifice of the main plunger, the volume of the secondary fluid chamber being selectively variable by translation of the secondary plunger rod; Wherein, when the umbrella valve is closed, the secondary fluid chamber is isolated from the outlet chamber, such that translation of the main plunger rod draws fluid into or dispenses fluid out of the main fluid chamber only via the outlet chamber; and Wherein, when the umbrella valve is open, the secondary fluid chamber is in fluid communication with the outlet chamber, such that translation of the secondary plunger rod dispenses fluid out of the secondary fluid chamber via the outlet chamber.

18. The syringe according to claim 17, wherein the secondary plunger rod has a locking mechanism having a locked engagement position with the main plunger to prevent accidental advancement of the secondary plunger and an unlocked engagement position to allow advancement of the secondary plunger and dispense fluid from the secondary fluid chamber into the outlet chamber.

19. The syringe according to claim 18, wherein the locking mechanism includes a twist-lock mechanism.

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