Therapeutic plasma exchange systems and methods

Abstract

To provide a system and a method for removing blood plasma from an object / patient, and delivering one or a plurality of kinds of substitution fluid / a therapeutic agent such as albumin.SOLUTION: The present invention includes a control unit configured and / or programed to monitor an amount of separated plasma that has been collected, suspend or end collection when a predetermined amount of plasma has been collected, and, after the predetermined amount of plasma has been collected, initiate delivery of a predetermined amount of substitution fluid / a therapeutic agent through a fluid substitution line 46 from a supply source.SELECTED DRAWING: Figure 4

Description

[Background technology]

[0001] The present disclosure relates to systems and methods for performing plasma exchange therapy, and more particularly, to simple plasma exchange (TPE). Even more particularly, the present disclosure relates to systems and methods for performing simple plasma exchange using an automated plasma exchange device to remove plasma from a subject / patient and deliver one or more replacement fluids / therapeutic agents, such as albumin.

[0002] Plasma exchange is an apheresis procedure in which whole blood is drawn from a subject, plasma is separated and collected from cellular blood components (red blood cells, platelets, and white blood cells), and the cells or formed blood components are returned to the subject. Simple plasma exchange ("TPE") is a plasma exchange method in which plasma is separated, collected, discarded, and replaced with fresh frozen plasma or a solution containing plasma proteins such as albumin. TPE is commonly used to treat several neurological and non-neurological conditions. Separation of plasma from cellular components is typically accomplished in an automated procedure by centrifugation or membrane filtration using a plasma exchange device to which a disposable fluid circuit is attached. The disposable fluid circuit includes one or more venipuncture needles that allow access to the blood vessels.

[0003] In TPE, whole blood is withdrawn from a subject / patient, mixed with an anticoagulant ("AC") in a specified ratio, and then separated into anticoagulated plasma and red blood cells and other formed elements. The separated plasma is collected in a plasma collection container while the formed elements are returned to the patient. A replacement fluid, providing therapeutic benefit and volume replacement, is typically administered to the patient and is often delivered with the formed elements to replace lost blood volume and lost proteins. The withdrawal of plasma and reinfusion of formed elements by infusion of replacement fluid can occur simultaneously, for example, when the disposable includes a venipuncture needle for the withdrawal of whole blood and a separate venipuncture for return of formed elements and infusion of replacement fluid (a "dual" or "double needle" configuration). Alternatively, when a "single needle" configuration fluid circuit is used, withdrawal and reinfusion / exchange of whole blood alternate. As mentioned above, the replacement fluid can be fresh frozen plasma, or a solution containing albumin or other protein, and, if necessary, an additional volume replacement fluid such as saline or other crystalloid solution.

[0004] The importance of TPE in the treatment of several diseases has prompted further efforts to develop systems, devices, and methods that can efficiently and safely remove plasma from patients and administer a desired amount of replacement fluid / therapeutic agent. Summary of the Invention

[0005] In one aspect, the present disclosure relates to a plasma exchange system for performing simple plasma exchange, including reusable hardware components and a disposable fluid circuit mounted thereon. The disposable fluid circuit includes a separator for separating whole blood into a plasma fraction and a formed element fraction, the separator having an input with a blood line integrally connected thereto for transporting whole blood from a subject to the separator. The separator includes a plasma output port integrally connected to a plasma collection container by a plasma line, and a formed element outlet port. The blood line terminates in a venipuncture needle for accessing the subject's vasculature and drawing whole blood from the subject. An anticoagulant line is integrally connected to the blood line and configured to be connected to a source of anticoagulant for transporting the anticoagulant to the blood line. A fluid replacement line is configured for delivering a replacement fluid / therapeutic agent to the subject, and includes a reinfusion line for transporting formed elements to the subject.

[0006] The reusable hardware components include a plurality of pumps for delivering anticoagulant to the blood line at a controlled rate during the collection phase, for delivering anticoagulated whole blood to the separator during the collection phase, for returning concentrated cellular components during the reinfusion phase, and for infusing a substitution fluid / therapeutic agent. The hardware components include a programmable controller configured to monitor the amount of separated plasma collected and to pause or terminate collection when a predetermined amount of plasma has been collected. The controller is also configured to initiate delivery of a predetermined amount of substitution fluid / therapeutic agent through the fluid replacement line from a source after collecting a predetermined amount of plasma.

[0007] In another aspect, the disclosure relates to a method for performing simple plasma exchange in a plasma exchange device that includes a disposable fluid circuit attached to reusable hardware components. The circuit includes a separation chamber, a venipuncture needle, a blood line in fluid communication with the venipuncture needle and an inlet of the separation chamber, a plasma product collection container in fluid communication with an outlet of the separation chamber, and a fluid substitution line in fluid communication with a source of substitution fluid / therapeutic agent. The method includes drawing whole blood from a subject, introducing the anticoagulated whole blood into the separation chamber, and separating the whole blood into plasma product and formed elements. The method further includes collecting a predetermined amount of plasma product in the plasma product container, returning the formed elements to the subject, and delivering an amount of substitution fluid / therapeutic agent to the subject via the substitution fluid line when a predetermined amount of plasma has been collected in the plasma product container.

[0008] In another aspect, the present disclosure relates to a method for performing simple plasma exchange in a plasma exchange device that includes a disposable fluid circuit attached to reusable hardware components. The circuit includes a separation chamber, a venipuncture needle, a blood line in fluid communication with the venipuncture needle and an inlet of the separation chamber, a plasma product collection container in fluid communication with an outlet of the separation chamber, and a substitution fluid line in fluid communication with a source of substitution fluid / therapeutic agent. The method further includes drawing whole blood from a subject, introducing the anticoagulated whole blood into the separation chamber, separating the whole blood into plasma product and formed elements, and collecting the plasma product in the plasma product container. The method further includes returning the formed elements to the subject, and delivering an amount of substitution fluid / therapeutic agent to the subject through the substitution fluid line when a predetermined amount of plasma product is collected in the plasma collection container. According to one aspect of the method disclosed herein, the infusion of the amount of substitution fluid / therapeutic agent delivered to the subject is monitored. [Brief description of the drawings]

[0009] FIG. 1 is a perspective view of an exemplary plasma exchange machine suitable for use in the TPE systems and methods of the present application.

[0010] FIG. 2 is a perspective view, with portions cut away to show detail, of a rotating membrane separator of the type incorporated into a disposable set that can be used in the TPE system of FIG.

[0011] FIG. 3 is a perspective view of one embodiment of the front panel of the TPE system of FIG. 1 showing the components of the disposable fluid circuit mounted thereon.

[0012] FIG. 4 is a schematic diagram illustrating the operation of the TPE system during the acquisition phase of the TPE procedure.

[0013] FIG. 5 is a schematic diagram illustrating the operation of the TPE system during the reinjection and exchange phases of the TPE procedure.

[0014] FIG. 6 is a schematic diagram of a control circuit including a control unit of the device of FIGS.

[0015] FIG. 7 is a schematic diagram showing a dual-needle TPE system. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] A more detailed description of the system and method according to the present disclosure is provided below. It should be understood that the following description of the specific device and method is intended to be illustrative and does not exhaust all possible variations or applications. Thus, the scope of the present disclosure is not intended to be limiting, but should be understood to encompass variations or embodiments that may occur to those skilled in the art.

[0017] In the context of the present application, therapeutic plasma exchange, and more specifically, TPE, is performed in an automated system that includes hardware components, generally designated 10, for collecting plasma from a subject / patient, and a disposable set or fluid circuit, generally designated 12 (FIG. 3). As described in more detail below with reference to FIGS. 1-5 and 7, the disposable fluid circuit 12 includes integrally connected separators, containers, and tubing for transporting blood and solutions within a sterile fluid pathway.

[0018] The separator 14, best seen in FIG. 2, may be a spinning membrane filter 16 mounted on a rotor 18 for rotation within a case 20 to separate blood into components. The separator 14 includes a gap or separation chamber 15 between the rotor 18 and the inner wall of the case 20. A detailed description of spinning membrane separators is provided in U.S. Pat. No. 5,194,145 to Schondorfer, which is incorporated herein by reference. As will be appreciated, in a different system, separation of whole blood may be accomplished by centrifugation. See, for example, U.S. Pat. No. 5,360,542 to Williamson et al.

[0019] During TPE, whole blood is drawn from the patient via a patient access device 36, such as a venipuncture needle (shown in Figures 4 and 5). The incoming whole blood is combined with anticoagulant from the container 13 at the junction of the whole blood line 34 and the anticoagulant line 48 in a selected ratio of whole blood to anticoagulant. The anticoagulated whole blood enters the separator 14 through the whole blood input port 22. The plasma is separated by a spinning membrane filter and then exits the plasma output port 24 through the plasma line 26 into the plasma collection container 28. In the single needle configuration shown in Figure 4, the concentrated cells are pumped from the separation chamber through the formed element output port 30 into the reservoir 32 where the cells remain until reinfused into the patient. When a dual needle fluid circuit configuration is used, as shown in Figure 7, the separated formed elements are pumped out of the separation chamber (without being in the reservoir) and reinfused into the patient.

[0020] The disposable fluid circuit 12 also includes (1) tubing lines defining a flow path for introducing whole blood into the system from the patient during collection (whole blood line 34 terminating in a venipuncture needle 36 (or needle 35 in FIG. 7 in a dual needle configuration) and returning formed cells to the patient during reinfusion; (2) tubing lines defining a flow path for transporting anticoagulated whole blood to a separator (blood line 38), a tubing line defining a flow path for transporting concentrated cells to a reservoir (cell line 40), (3) a tubing line defining a flow path for transporting concentrated cells from the reservoir to the blood line in a single needle configuration (reinfusion line 42), (4) a tubing line defining a flow path for flushing plasma into a plasma collection container (plasma line 44), and (5) a tubing line defining a flow path for infusing a replacement fluid including a drug and / or therapeutic agent (replacement fluid line 46), and (6) a tubing line defining a flow path for transporting an anticoagulant to the whole blood.

[0021] The hardware components 10 include a programmable control 50 and a touch screen 52 with a graphical user interface ("GUI") for an operator to control the procedure. For example, the GUI allows entry of any of the following: patient ID, patient gender, patient height, patient weight, patient age, patient hematocrit / hemoglobin, target replacement fluid infusion volume, and target plasma volume. The touch screen 52 also allows the operator to gather status information and handle error conditions.

[0022] Typically, the hardware component 10 includes multiple pumps for transporting whole blood, separated and formed elements, replacement fluids including therapeutic and / or therapeutic agents, and anticoagulants through the fluid circuit. In one embodiment, three pumps are located on the front panel of the hardware component 10, including an AC pump 54, a blood pump 56, and a cell pump 58. As further shown in the figure, the pumps are peristaltic pumps. The AC pump 54 delivers anticoagulant solution (AC) to the blood line 34 at a controlled rate as the whole blood enters the circuit from the patient. The blood pump 56 delivers anticoagulated whole blood to the separator during the collection phase of the procedure and returns concentrated cellular components and replacement fluids to the patient during the exchange phase of the procedure. The cell pump 58 delivers formed or cellular components and replacement fluids / therapeutic and / or therapeutic agents from the separator 14 to a reservoir during the collection phase or to the patient during the reinfusion phase, as shown in the dual needle configuration of FIG. 7.

[0023] The front panel also typically includes a number of flow control devices for selectively opening and closing the flow paths as needed during the TPE procedure. As shown in the figure, in one embodiment, the hardware component 10 includes four clamps to which the tubing segments of the disposable circuit 12 are attached, including a reinfusion clamp 60, a blood clamp 62, a substitution fluid clamp 64, and a plasma clamp 66. The reinfusion clamp 60 closes to block the reinfusion line (42) during the collection phase and opens during the reinfusion phase to reinfuse formed elements (from the single-needle reservoir 32) into the subject / patient. The blood clamp 62 opens during the collection phase to allow pumping of anticoagulated whole blood to the separator 14 and closes during the reinfusion phase to block the blood line 38. The substitution fluid clamp 64 closes to block the substitution fluid line 46 during the collection phase and opens during the infusion of substitution fluid and / or therapeutic agents and / or drugs. The plasma clamp 66 opens during the collection phase to allow plasma to flow into the plasma collection container 28 and closes during the reinfusion phase.

[0024] Similar to the pumps and clamps described above, the hardware component 10 may include one or more weighing scales from which the source fluid and collected fluid containers may be suspended. The weighing scales may be associated with or include weight sensors for monitoring the delivery and collection of fluids. For example, as shown in the figure, the hardware component 10 may include multiple weighing scales for monitoring the amount of fluid delivered or collected, such as plasma collection volume (scale 68), AC solution volume (scale 70), and formed element volume (scale 72). In other embodiments, a single weighing scale may be provided on the hardware component from which one or more containers may be suspended, as needed or desired. As described below, the scales 68, 70, 72 may also be used to monitor the amount of fluid in other containers used during the TPE procedure. The system may also include additional sensors and detectors, including a venous pressure sensor 74, a separator pressure sensor 76, an optical blood detector 78, and an air detector 80. The pumps, clamps, weighing scales, and other detectors communicate with the programmable controller 50, as described next.

[0025] FIG. 6 is a schematic diagram of a control unit or “controller” 50 included in the hardware component 10. The controller 50 may include a microprocessor 304 (which may include multiple physical and / or virtual processors). According to other embodiments, the controller 50 may include one or more electrical circuits designed to perform the actions described herein. In one embodiment, the controller 50 may include a microprocessor and other circuits or circuitry. Additionally, the controller 50 may include one or more memories 306. Instructions with which the microprocessor 304 is programmed may be stored in the memory 306 associated with the microprocessor 304, which memory / memories 306 may include one or more tangible, non-transitory, computer-readable memories having stored thereon computer-executable instructions that, when executed by the microprocessor 304, cause the microprocessor 304 to perform one or more actions as described herein.

[0026] As also shown in FIG. 6, the controller 50 may be coupled to one or more of the above structures to control the operation of the structures, for example to receive information (e.g., in the form of a signal) from these structures or to provide instructions (e.g., in the form of a signal) to these structures. As shown in FIG. 6, the controller 50 may be coupled to one or more scales 68, 70, 72 (seen in FIG. 3) that hold the solution containers or containers provided for collecting blood components, sensors associated with the clamps 60, 62, 64, 66, and at least one input 52 for receiving information from these devices. Furthermore, the controller 50 may be coupled to the pumps 54, 56, 58 and the drive unit of the separator 14 to provide instructions to these devices and control their operation. It may also be possible for the controller 50 to receive information and provide instructions from a given structure, such as one of the structures already mentioned. The controller 50 may be directly electrically connected and coupled to these structures, or the controller 50 may be directly connected to other intermediate devices that are directly connected and coupled to these structures. The control unit 50 can also calculate or estimate values ​​(flow rates, injection volumes, etc.) in response to data entered by the operator and / or signals or other information received from the structures described above.

[0027] The at least one input 52 may include a number of different devices according to the embodiments described herein. For example, the input 52 may include a keyboard or keypad through which a user may provide information and / or instructions to the controller 50. Alternatively, the input 52 may be a touch screen such as may be used in conjunction with a video display 308 disposed on the front panel of the hardware component 10. The video display 308 is also coupled to the controller 50. The assembly of the input / touch screen 52 and the video display 308 may be one of the previously described structures to which the controller 50 is coupled and from which the controller 50 receives information and from which the controller 50 provides instructions.

[0028] According to the TPE methods described herein, the patient is connected to the system throughout the procedure. As illustrated in Figures 4 and 5, the disposable fluid circuit 12 includes a single venipuncture needle 36, through which whole blood is drawn from the donor during the collection phase (Figure 4), concentrated cells are returned to the donor during the reinfusion phase (Figure 5), and replacement fluid / therapeutic and / or therapeutic agents are infused during the exchange phase. However, a "dual needle" circuit will be understood in which whole blood is drawn from the patient through a first venipuncture needle while replacement fluid containing formed elements and therapeutic and / or therapeutic agents is infused through a second venipuncture needle. Figure 7 illustrates the dual needle option using a second venipuncture needle 35.

[0029] At least some of the TPE procedures using a single needle configuration according to the present disclosure can be performed in multiple cycles, each cycle having a collection / separation phase followed by a reinfusion phase. Once all cycles of collection / separation and reinfusion are completed, the method further includes an exchange phase in which a replacement fluid / therapeutic agent is delivered to the patient. In the collection phase, whole blood is separated into plasma and concentrated cells. As described above, the disposable fluid circuit includes a plasma collection container 28 for receiving the separated plasma and a reservoir 32 for receiving the formed elements. During the reinfusion phase, the formed cells from the reservoir 32 are reinfused into the patient via the venipuncture needle 36 in a "single-needle" TPE procedure. Typically, TPE performed with a single venipuncture needle 36 includes multiple cycles of collection and reinfusion, with partial collection of the collected plasma alternating with a reinfusion phase in which the collected formed elements are returned to the reservoir 32. This cycle is repeated until a predetermined amount of plasma product is collected.

[0030] Returning to Figure 4, during the collection phase, anticoagulant solution (AC) is pumped at a controlled rate and mixed with the whole blood as it enters the disposable set 12. The anticoagulated blood is pumped to separator 14 where the plasma is separated from the formed fraction and directed to plasma collection container 28. The formed fraction is pumped from separator 14 to reservoir 32. The collection phase stops when reservoir 32 reaches the expected amount of concentrated cells or, as described above, when a predetermined target plasma collection volume has been achieved.

[0031] Once all of the collection / separation and reinfusion cycles are complete, the exchange phase can begin. The exchange phase involves the infusion of replacement fluid / therapeutic agent from the container 17. The replacement fluid / therapeutic agent is pumped from the container 17 by pump 58 in response to commands from the control unit 50 and / or by blood pump 56 (in the reverse direction) as shown in FIG. 5. In the single-needle embodiment as shown in FIG. 5, the replacement fluid / therapeutic agent is pumped from the container 17 (17') through the fluid replacement line 46, through the separator 14, the reservoir 32, the reinfusion line 42, the blood line 34, through the venipuncture needle 36 to the patient. Alternatively, the replacement fluid / therapeutic agent can be pumped (by pump 56) through line 38 and the blood line 34 and the venipuncture needle 36 to the patient.

[0032] In a dual-needle embodiment of the type shown in Figure 7, the replacement fluid / therapeutic agent is pumped from container 17 (17') through fluid replacement line 46, through separator 14, air trap 33 (instead of reservoir 32), and conversion needle 35 to the patient. In a dual-needle procedure, the collection and reinfusion steps occur simultaneously.

[0033] As indicated above, the replacement fluid / therapeutic agent for TPE procedures may be plasma, such as fresh frozen plasma, or an albumin solution, which replenishes lost volume and provides a therapeutic benefit to the patient. As described below, the replacement fluid / therapeutic agent may also include saline, which similarly helps replenish lost volume and may also have beneficial therapeutic effects. The replacement fluid / therapeutic agent container 17 may be pre-attached to the fluid circuit 12, or, more commonly, may be attached to the circuit 12 at the time of use. The container 17 may be hung from a free-standing standard IV pole or from a hook on the hardware component 10.

[0034] The amount of substitution fluid / therapeutic agent administered to the patient can be monitored by the pump revolutions or pump stroke rate of pumps 56, 58. Once a predetermined amount of substitution fluid / therapeutic agent has been delivered to the patient, pumping ceases.

[0035] In an alternative embodiment, the amount of substitution fluid administered to the patient can be monitored by sensing the change in weight (and therefore volume) of the container 17 during the infusion of the substitution fluid / therapeutic portion of the exchange phase. In this embodiment, the method involves removing the container 17 from the IV pole or hook and hanging it from a weigh scale or one of a number of available weigh scales 68, 70, 72 just prior to the start of the exchange phase. For example, once a predetermined (partial or total) target volume of plasma has been collected, the weigh scale 68 sends a signal to the control unit 50 that plasma collection is complete. Upon receiving an instruction or prompt, the operator can remove the plasma container 28 from the weigh scale 68 and move the substitution fluid / therapeutic container 17 from the IV pole / hook and place it on the weigh scale 68. The weigh scale monitors the infusion of the substitution fluid / therapeutic in the container 17 until the predetermined amount of substitution fluid / therapeutic is delivered to the patient. Of course, it will be understood that other available weigh scales (70, 72) can be used in place of the weigh scale 68.

[0036] In a further alternative embodiment for monitoring the amount of substitution fluid delivered to the patient, the container 17 may contain a fixed amount of substitution fluid / therapeutic agent all that is to be delivered to the patient. In this embodiment, the substitution fluid line 46 may be associated with a detector, such as an air detector 80 (FIG. 1). Infusion of substitution fluid / therapeutic agent continues until the detector 80 senses the presence of air in the line 46 and sends a signal to the controller 50 to stop rotating the pumps 56, 58, thereby ceasing delivery of the substitution fluid / therapeutic agent.

[0037] The volume of replacement fluid / therapeutic agent needed or desired may vary from patient to patient. For example, in some embodiments, the volume may be a fixed amount that is entered by the operator using a user interface. Once entered, the controller continues infusing the replacement fluid / therapeutic agent until the entered target volume is reached.

[0038] In another embodiment, the volume of replacement fluid / therapeutic agent delivered may be calculated by the controller as a percentage of the total volume of plasma product or raw plasma collected from the patient. For example, the controller may be preprogrammed to collect 25% (or some other percentage) of the actual plasma or raw plasma collected from the donor. As part of the replacement fluid / therapeutic agent infusion, it is necessary to determine the amount of raw plasma that can be safely removed from the patient. Since the volume of plasma product collected in the plasma container 28 includes both plasma and an amount of anticoagulant, the controller calculates the amount of plasma in the plasma product to be collected and whether that amount matches the target amount of plasma product. Once the predetermined target amount of plasma is reached (measured by gravimeter 68) and the formed elements are reinfused, plasma collection may stop and replacement fluid / therapeutic agent infusion may begin as a predetermined percentage of the collected plasma, all under the direction of the controller.

[0039] Occasionally, for example, due to a patient condition or device malfunction, plasma collection may need to be terminated before collecting the targeted, initially determined, or desired amount of plasma. In such cases, the system determines the amount of plasma actually collected and adjusts the volume of replacement fluid / therapeutic agent delivered to the patient as a percentage of the plasma actually collected. For example, if the desired or initially determined volume of plasma available for collection is 800 mL, but only 600 mL is collected, the system adjusts the amount of replacement fluid / therapeutic agent to the selected percentage or ratio of plasma to replacement fluid / therapeutic agent. Thus, continuing with the present example where only 600 mL of the desired 800 mL is collected and the percentage of replacement fluid / therapeutic agent is selected to be 25% of the plasma volume removed from the patient, the control unit adjusts the amount of replacement fluid / therapeutic agent to be delivered from 200 mL to 150 mL.

[0040] In another aspect, the system can be configured or programmed to deliver the replacement fluid / therapeutic agent to the patient in stages or portions. Once the volume of replacement fluid / therapeutic agent to be delivered is determined, the injection can proceed in increments or as a percentage of the total amount to be delivered. Thus, a portion of the replacement fluid / therapeutic agent can be delivered at one point in the procedure and the remainder can be delivered at another point in the procedure. The incremental injection of replacement fluid / therapeutic agent can be performed, in one alternative embodiment, as part of a collection / separation and reinjection cycle to protect against excessive fluid volume shortages during the TPE procedure.

[0041] In yet another aspect, the system can be configured or programmed to deliver two or more replacement fluids and / or therapeutic agents using the same plasma exchange machine. The disposable fluid circuit 12 may include separate containers of different replacement fluids and / or therapeutic agents, each in fluid communication with the replacement fluid line 46, as shown in FIG. 5 (dashed line). The controller can be programmed to selectively open and close the clamps, thereby selectively opening and closing the flow paths 17, 17' to allow the flow of two (or more) fluids. Alternatively, the containers 17, 17' may be coupled by a (three-way) valve 19, which, under the direction of the controller, can be opened and closed to selectively allow and block flow from the containers. In one embodiment, an albumin solution (in container 17) may be the first fluid and saline solution (in container 17') may be the second fluid, and the controller is programmed to infuse the albumin at one point in the TPE procedure and the saline at another point in the TPE procedure.

[0042] The volume of replacement fluid / therapeutic agent delivered to the patient can be established by an established protocol or can be tailored to the patient undergoing TPE according to the systems and methods disclosed herein. As noted above, in one embodiment, the volume of replacement fluid / therapeutic agent can be a pre-programmed percentage of the plasma available for collection from the patient or the total plasma product to be collected. The plasma available for collection and / or the total plasma product to be collected can be determined by a pre-programmed nomogram similar to that described with respect to a particular plasma exchange (plasma collection) protocol in International Application No. PCT / US19 / 33318, filed May 21, 2019, the contents of which are incorporated herein by reference. As described in this referenced international application, the plasma available for collection and / or the total plasma product to be collected can be based on certain parameters of the subject undergoing plasma exchange, such as, but not limited to, the subject's total plasma volume, hematocrit value, and further the subject's height, weight, sex, age, etc. Thus, the system, under the direction of the controller, can receive the above types of patient data and calculate the amount of plasma that can be safely collected from a given patient based on the pre-programmed nomogram. Once the control unit calculates the amount of plasma that can be collected and / or the predetermined target plasma volume, the control unit can calculate / estimate the volume of replacement fluid / therapeutic agent required for infusion, whether as a percentage of the calculated plasma volume or based on other factors.

[0043] Alternatively, the volume of replacement fluid / therapeutic agent delivered to the patient may be more directly calculated or estimated based on patient parameters. In that regard, the control unit may be pre-programmed with one or more nomograms that estimate or calculate the volume of replacement fluid / therapeutic agent to be infused based on hematocrit value and, more specifically, one or more donor characteristics including the patient's height, weight, sex, and age.

[0044] Other Examples Aspect 1. A plasma exchange system for performing therapeutic plasma exchange comprising reusable hardware components and a disposable fluid circuit, the disposable fluid circuit comprising: i) a separator for separating whole blood into plasma and formed fractions, the separator having an input having a blood line integrally connected thereto for transporting whole blood from a subject to the separator, a plasma output port integrally connected by a plasma line to a plasma collection container, and a formed fraction outlet port; ii) the blood line terminating in a venipuncture needle for transporting whole blood from a subject to the blood line; iii) an anticoagulant line integrally connected to the blood line and configured for connection to a source of anticoagulant for transporting anticoagulant to the blood line; and iv) a replacement fluid / therapeutic agent for delivery to a subject. and v) a reinfusion line for transporting formed elements to the subject, wherein a) the reusable hardware components comprise a plurality of pumps for delivering anticoagulant to the blood line at a controlled rate during a collection phase, delivering anticoagulated whole blood to the separator during the collection phase and returning concentrated cellular components during a reinfusion phase, and returning concentrated cellular components from the separator to reinfuse replacement fluid / therapeutic agent, and a programmable controller configured to: i. monitor the amount of separated plasma collected and pause or terminate collection once a predetermined amount of plasma has been collected; and ii. initiate delivery of a predetermined amount of replacement fluid / therapeutic agent via the fluid replacement line from a source after the predetermined amount of plasma has been collected.

[0045]

[0023] Aspect 2. The system of aspect 1, wherein the therapeutic agent comprises albumin.

[0046]

[0023] Aspect 3. The system of aspect 1 or aspect 2, wherein the fluid circuit further comprises a reservoir integrally connected to the component port of the separator.

[0047]

[0023] Aspect 4. The system of aspect 1 or aspect 2, wherein the disposable fluid circuit includes a first venipuncture needle for transporting whole blood from a subject and a second venipuncture needle for returning the formed elements and delivering the replacement fluid / therapeutic agent to the subject.

[0048]

[0023] Aspect 5. The system of any one of aspects 1 to 3, wherein the hardware components include one or more weigh scales configured to receive a source of replacement fluid / therapeutic agent.

[0049]

[0023] Aspect 6. The system of any one of aspects 1 to 4, wherein the fluid replacement line is in releasable fluid communication with the reinfusion line.

[0050]

[0023] Aspect 7. The system of aspect 5, wherein the reinfusion line is in fluid communication with the blood line and the venipuncture needle.

[0051] Aspect 8. The system of aspect 4, wherein the fluid replacement line is in fluid communication with the second venipuncture needle.

[0052] Aspect 9. A method for performing therapeutic plasma exchange in a plasma exchange machine with a disposable fluid circuit attached to reusable hardware components, the circuit including a separation chamber, a venipuncture needle, a blood line in fluid communication with the venipuncture needle and an inlet of a separation chamber, a plasma product collection container in fluid communication with an outlet of the separation chamber, and a substitution fluid line in fluid communication with a source of substitution fluid / therapeutic agent, the method comprising: a. drawing whole blood from a subject and introducing anticoagulated whole blood into the separation chamber, b. separating the whole blood into product plasma and formed elements, c. collecting a predetermined amount of the product plasma in a plasma product container, d. returning the formed elements to the subject, and e. delivering a quantity of substitution fluid / therapeutic agent to the subject via the substitution fluid line when the predetermined amount of product plasma is collected in the plasma collection container.

[0053]

[0023] Aspect 10. The system of any one of aspects 1 to 8, wherein the controller is further configured to monitor an amount of the replacement fluid / therapeutic agent delivered to the subject.

[0054]

[0023] Example 11. The system of any one of examples 1 to 8, further comprising a sensor that sends a signal to the controller when a predetermined amount of the replacement fluid / therapeutic agent has been delivered to the subject.

[0055]

[0023] Aspect 12. The system of any one of aspects 1 to 8, further comprising a sensor that sends a signal to the controller when the injection of the replacement fluid / therapeutic agent is complete.

[0056] Aspect 13. The system of any one of aspects 1 to 8, wherein the controller is further configured to calculate an amount of replacement fluid / therapeutic agent to be delivered to the subject, the amount of therapeutic agent delivered being based on a percentage of plasma / therapeutic agent collected.

[0057] Aspect 14. The system of aspect 13, wherein the controller is further configured to pause or terminate the infusion of the replacement fluid / therapeutic agent when the amount of replacement fluid / therapeutic agent is delivered to the subject based on the ratio of collected plasma / therapeutic agent.

[0058]

[0023] Aspect 15. The system of any one of aspects 1 through 8 and aspects 10 through 14, wherein the amount of the replacement fluid / therapeutic agent is a portion of a total volume of the therapeutic agent to be delivered, and the controller is further configured to pause the infusion of the therapeutic agent when the portion has been delivered to the subject.

[0059]

[0023] Aspect 16. The system of any one of aspects 1 through 8, and aspects 10 through 15, wherein the disposable kit includes both a container of volume displacement fluid and a container of the therapeutic agent.

[0060] Aspect 17. The system of aspect 16, wherein the volumetric replacement fluid container and the therapeutic agent container are in releasable fluid communication with the replacement fluid line.

[0061] Aspect 18. The system of aspect 17, further comprising one or more flow controls for establishing a flow of the volumetric replacement fluid through the replacement fluid line while preventing a flow of the therapeutic agent through the replacement fluid line.

[0062]

[0023] Aspect 19. The system of aspect 18, wherein the one or more flow control devices include a three-way valve.

[0063]

[0023] Aspect 20. The system of any one of aspects 1 to 8, and aspects 10 to 19, wherein the controller is configured to calculate a target volume of plasma to be collected based on at least two of the subject's height, weight, sex, age, and hematocrit.

[0064] Aspect 21. The system of aspect 20, wherein the controller is configured to calculate an amount of the treatment agent to be delivered based on the calculated target volume of plasma to be collected.

[0065]

[0023] Embodiment 22. The system of any one of embodiments 1 to 8, and embodiments 10 to 21, comprising a reservoir in fluid communication with the second outlet on the separation chamber for receiving separated formed components.

[0066]

[0023] Aspect 23. The system of any one of aspects 1 through 8, and aspects 10 through 21, wherein the disposable fluid circuit includes a first venipuncture needle for transporting whole blood from a subject and a second venipuncture needle for returning the formed elements and delivering the replacement fluid / therapeutic agent to the subject.

[0067] Aspect 24. A method for performing therapeutic plasma exchange in a plasma exchange device including a disposable fluid circuit attached to reusable hardware components, the circuit including a separation chamber, a venipuncture needle, a blood line in fluid communication with the venipuncture needle and an inlet of a separation chamber, a plasma product collection container in fluid communication with an outlet of the separation chamber, and a substitution fluid line in fluid communication with a source of substitution fluid / therapeutic agent, the method comprising: a. drawing whole blood from a subject and introducing anticoagulated whole blood into the separation chamber, b. separating the whole blood into product plasma and formed elements, c. collecting the product plasma in a plasma product container, d. returning the formed elements to the subject, e. delivering a quantity of substitution fluid / therapeutic agent via the substitution fluid line to the subject when a predetermined quantity of product plasma is collected in the plasma collection container, and f. monitoring the infusion of the quantity of substitution fluid / therapeutic agent delivered to the subject.

[0068]

[0023] Aspect 25. The method of aspect 24, comprising monitoring the amount of the replacement fluid / therapeutic agent delivered by suspending a container of the replacement fluid / therapeutic agent from a scale of the reusable hardware component.

[0069] Aspect 26. The method of aspect 24 or aspect 25, wherein the monitoring comprises detecting a presence of air in the replacement fluid line during the delivery.

[0070]

[0031] Aspect 27. The method of any one of aspects 24 to 26, comprising withdrawing whole blood through the venipuncture needle and delivering the replacement fluid / therapeutic agent through the venipuncture needle.

[0071]

[0031] Aspect 28. The method of any one of aspects 24 to 27, comprising collecting the formed elements in the reservoir.

[0072]

[0031] Example 29. The method of any one of examples 24 to 28, comprising determining an amount of replacement fluid / therapeutic agent to be delivered to the subject.

[0073]

[0023] Aspect 30. The method of aspect 29, comprising determining the amount of replacement fluid / therapeutic agent delivered to the subject based on a predetermined amount of plasma product collected.

[0074]

[0023] Aspect 31. The method of aspect 29, comprising determining the amount of the therapeutic agent to be delivered based on the amount of plasma product collected in the plasma container.

[0075]

[0023] Embodiment 32. The method of any one of embodiments 24 to 31, wherein said predetermined amount of plasma is based on at least two of the subject's height, weight, sex, and hematocrit.

[0076]

[0036] Aspect 33. The method of any one of aspects 24 to 32, wherein the amount of replacement fluid / therapeutic agent delivered is a portion of a total amount of therapeutic agent delivered to the subject.

[0077]

[0036] Aspect 34. The method of aspect 33, comprising pausing said delivery of said replacement fluid / therapeutic agent.

[0078]

[0023] Embodiment 35. The method of any one of embodiments 24 to 34, further comprising delivering an amount of volume displacement fluid to said subject.

[0079] Aspect 36. The method of aspect 35, comprising delivering the therapeutic agent separately from delivering the volume displacement fluid.

[0080]

[0023] Aspect 37. The method of aspect 35 or aspect 36, comprising monitoring the amount of volume displacement fluid delivered to the subject.

[0081]

[0023] Embodiment 38. The method of any one of embodiments 9 and 24 to 37, wherein the fluid circuit includes a reservoir in fluid communication with an outlet of the separator, and the method further includes delivering the separated formed components to the reservoir.

[0082]

[0036] Aspect 39. The method of aspect 38, further comprising reinjecting said formed elements into said patient through said venipuncture needle.

[0083]

[0023] Aspect 40. The method of aspect 39, comprising withdrawing said whole blood and reinjecting said formed elements in repeated cycles.

[0084] Embodiment 41. The method of embodiment 40, further comprising delivering said replacement fluid / therapeutic agent after a final cycle.

[0085]

[0023] Aspect 42. The method of any one of aspects 9 and aspects 24 through 37, wherein the fluid circuit includes a first venipuncture needle and a second venipuncture needle, and the method includes withdrawing the whole blood through the first venipuncture needle and reinjecting the formed elements through the second venipuncture needle.

[0086] Aspect 43. The method of aspect 42, further comprising delivering said replacement fluid / therapeutic agent through said second venipuncture needle after said reinfusion of said formed elements.

[0087] It will be understood that the described embodiments are illustrative of some of the applications of the principles of the present subject matter. Numerous modifications may be made by those skilled in the art without departing from the spirit and scope of the claimed subject matter, including combinations of features individually disclosed or claimed herein. For these reasons, the scope of the claims should not be limited to the above description, but should be as set forth in the following claims.

Claims

1. 1. A plasma exchange system for performing therapeutic plasma exchange comprising reusable hardware components and a disposable fluid circuit, a) the disposable fluid circuit comprises: i) a separator for separating whole blood into plasma and formed element fractions, the separator having an input having a blood line integrally connected thereto for transporting whole blood from a subject to the separator, a plasma output port integrally connected by a plasma line to a plasma collection container, and a formed element outlet port; ii) the blood line terminating in a venipuncture needle for transporting whole blood from a subject to the blood line; iii) an anticoagulant line integrally connected to the blood line and configured for connection to a source of anticoagulant for transporting anticoagulant to the blood line; iv) a fluid replacement line configured to deliver a replacement fluid / therapeutic agent to the subject; and v) a reinfusion line for transporting formed elements to the subject; b) the reusable hardware components comprise a plurality of pumps for delivering anticoagulant to the blood line at a controlled rate during a collection phase, delivering anticoagulated whole blood to the separator during the collection phase and returning concentrated cellular components during a reinfusion phase, returning concentrated cellular components from the separator and infusing replacement fluid / therapeutic agents, and a programmable controller, the programmable controller comprising: i. monitoring the amount of separated plasma collected and pausing or terminating collection once a predetermined amount of plasma has been collected; ii. A system configured to initiate delivery of a volume of replacement fluid / therapeutic agent from a source through the fluid replacement line after collecting the volume of plasma and reinfusing the concentrated cellular components.

2. The system of claim 1 , wherein the therapeutic agent comprises albumin.

3. 3. The system of claim 1 or claim 2, wherein the fluid circuit further comprises a reservoir integrally connected to the component port of the separator.

4. 3. The system of claim 1 or claim 2, wherein the disposable fluid circuit includes a first venipuncture needle for transporting whole blood from a subject and a second venipuncture needle for returning the formed elements to the subject and delivering the replacement fluid / therapeutic agent.

5. The system of claim 1 , wherein the hardware components include one or more weighing scales configured to receive a source of replacement fluid / therapeutic agent.

6. 5. The system of claim 1, wherein the fluid replacement line is in reclosable fluid communication with the reinfusion line.

7. The system of claim 5 , wherein the reinfusion line is in fluid communication with the blood line and the venipuncture needle.

8. The system of claim 4 , wherein the fluid replacement line is in fluid communication with the second venipuncture needle.

9. The system of claim 1 , wherein the control unit is further configured to monitor the amount of the replacement fluid / therapeutic agent delivered to the subject.

10. 9. The system of claim 1, further comprising a sensor that sends a signal to the controller when a predetermined amount of the replacement fluid / therapeutic agent has been delivered to the subject.

11. 9. The system of claim 1, further comprising a sensor that sends a signal to the controller when the delivery of the replacement fluid / therapeutic agent is complete.

12. 9. The system of claim 1, wherein the control unit is further configured to calculate an amount of replacement fluid / therapeutic agent to be delivered to the subject, the amount of therapeutic agent to be delivered being based on a percentage of plasma collected.

13. 13. The system of claim 12, wherein the control unit is further configured to pause or terminate the infusion of the therapeutic agent when the amount of replacement fluid / therapeutic agent has been delivered to the subject based on the percentage of collected plasma.

14. 14. The system of claim 1, wherein the amount of replacement fluid / therapeutic agent is a portion of a total amount of the therapeutic agent to be delivered, and the control unit is further configured to pause the infusion of the therapeutic agent when the portion has been delivered to the subject.

15. 15. The system of claim 1, wherein the disposable fluid circuit includes both a reservoir of volume replacement fluid and a reservoir of the therapeutic agent.

16. The system of claim 15 , wherein the volume replacement fluid container and the therapeutic agent container are in releasable fluid communication with the fluid replacement line.

17. 17. The system of claim 16, further comprising one or more flow controls for establishing a flow of the volumetric replacement fluid through the fluid replacement line while preventing a flow of the therapeutic agent through the fluid replacement line.

18. The system of claim 17 , wherein the one or more flow control sections include a three-way valve.

19. 19. The system of claim 1, wherein the control unit is configured to calculate a target volume of plasma to be collected based on at least two of the subject's height, weight, sex, age, and hematocrit.

20. 20. The system of claim 19, wherein the controller is configured to calculate an amount of the therapeutic agent to be delivered based on the calculated target volume of plasma to be collected.

21. 21. The system of claim 1 , further comprising a reservoir in fluid communication with a second outlet on the separator for receiving separated formed components.

22. 21. The system of claim 1, wherein the disposable fluid circuit includes a first venipuncture needle for transporting whole blood from a subject and a second venipuncture needle for returning the formed elements to the subject and delivering the replacement fluid / therapeutic agent.

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