WO2025179108A1 - Adaptive total blood volume algorithm - Google Patents

Abstract

A method for determining minimum or maximum total blood volume of a donor for a blood processing procedure, using a blood processing device including a controller. The method includes inputting at least one donor characteristic for a donor, performing at least two separate total blood volume calculations to produce at least a first total blood volume and a second total blood volume, and selecting the lowest total blood volume as the minimum total blood volume of the donor or selecting the highest total blood volume for the maximum total blood volume of a donor.

Description

ADAPTIVE TOTAL BLOOD VOLUME ALGORITHM

RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application Serial No. 63/557,041 , filed on February 23, 2024, the disclosure of which is hereby incorporated by reference in its entirety.

Background

Field of the Disclosure

The invention relates to adaptive algorithms for determining total blood volume. More particularly, this invention relates to adaptive algorithms that may be employed during separation and collection of blood components based on minimum and maximum values of multiple total blood volume calculation methods.

Description of Related Art

Various blood processing systems now make it possible to collect particular blood constituents, instead of whole blood, from a blood source. Typically, in such systems, whole blood is drawn from a blood source, the particular blood component or constituent is separated, removed, and collected, and the remaining blood constituents are returned to the blood source. Removing only particular constituents is advantageous when the blood source is a human donor, because potentially less time is needed for the donor's body to return to pre-donation levels, and donations can be made at more frequent intervals than when whole blood is collected. This increases the overall supply of blood constituents, such as plasma and platelets, made available for transfer and/or therapeutic treatment.

According to one approach, whole blood may be separated into its constituents through centrifugation. The centrifuge rotates the separation chamber of the disposable flow circuit during processing, causing the heavier (greater specific gravity) components of the whole blood in the separation chamber, such as red blood cells, to move radially outwardly away from the center of rotation toward the outer or "high-G" wall of the separation chamber. The lighter (lower specific gravity) components, such as plasma, migrate toward the inner or "low-G" wall of the separation chamber. The boundary that forms between the heavier and lighter components in the separation chamber is commonly referred to as the interface. Various ones of these components can be selectively removed from the whole blood by providing appropriately located channeling structures and outlet ports in the flow circuit. For example, in one blood separation procedure, plasma is separated from cellular blood components and collected, with the cellular blood components and a replacement fluid being returned to the blood source. Alternatively, red blood cells may be harvested from the separation chamber and the rest of the blood constituents returned to the donor. Other processes are also possible including, without limitation, platelet collection, red blood cell exchanges, plasma exchanges, etc.

While many blood separation systems and procedures have employed centrifugal separation principles, there is another class of devices, based on the use of a membrane, that has been used for plasmapheresis (i.e., separating plasma from whole blood). More specifically, this type of device employs relatively rotating surfaces, at least one or which carries a porous membrane. Typically, the device employs an outer stationary housing and an internal spinning rotor covered by a porous membrane. Blood is fed into an annular space or gap between the rotor and the housing. The blood moves along the longitudinal axis of the housing toward an exit region, with plasma passing through the membrane and out of the housing into a collection bag. The remaining blood components, primarily red blood cells, platelets, and white blood cells, move to the exit region between the rotor and the housing and then are returned to the donor or conveyed into a collection bag.

It should be understood that blood separation may be achieved by a variety of approaches, and that centrifugation and separation via spinning membrane are merely two exemplary approaches to blood separation.

Regardless of the particular approach that is employed for separating blood into two or more constituents, it is helpful for the controller of the hardware to determine or be provided with the total blood volume of a donor in order to achieve a target yield for one or more target blood components. The total blood volume of a donor may be determined or selected by any of a number of approaches. While there are many methods that have been applied and use various characteristics (such as sex, height, weight) of a person/donor, there is not a recommended standard considered most accurate. As such, many different models are applied in different medical settings.

It is important to accurately determine the total amount of blood of the donor. This total blood volume of the donor can be used to determine the amount of blood to be processed, or how much can be processed. If an insufficient amount of blood is processed, the target yield for the one or more target blood components will not be reached. If too much blood is processed, the procedure takes more time than is necessary, unnecessarily depletes the blood source, and may diminish the quality of the collected component (e.g., if more platelets are present in a collection bag than may be accommodated by a platelet storage solution). This is especially relevant when the biological sex of a donor is unknown and the risk of overdrawing of blood is much higher.

It is, therefore, desirable to utilize a method/algorithm for estimating total blood volume which is able to calculate a more accurate minimum or maximum total blood volume by applying values of at least two different calculation modules to determine a minimum or maximum predicted total blood volume.

Summary

There are several aspects of the present subject matter which may be embodied separately or together in the devices and systems described and claimed below. These aspects may be employed alone or in combination with other aspects of the subject matter described herein, and the description of these aspects together is not intended to preclude the use of these aspects separately or the claiming of such aspects separately or in different combinations as set forth in the claims appended hereto.

In one aspect, there is a method for determining minimum total blood volume of a donor for a blood processing procedure. The method uses a blood processing device including a controller. The method includes inputting at least one donor characteristic for a donor, performing at least two separate total blood volume calculations to produce at least a first total blood volume and a second total blood volume; and selecting the lowest total blood volume as the minimum total blood volume of the donor.

In another aspect, there is a method for determining maximum total blood volume of a donor for a blood processing procedure. The method uses a blood processing device including a controller. The method includes inputting at least one donor characteristic for a donor, performing at least two separate total blood volume calculations to produce at least a first total blood volume and a second total blood volume; and selecting the largest total blood volume as the maximum total blood volume of the donor.

In yet another aspect, there is a blood processing device which includes a separator, a pump system, and a controller. The controller is configured to perform at least two separate total blood volume calculations based on inputted donor characteristics to produce at least a first total blood volume and a second total blood volume, select the lowest total blood volume as the minimum total blood volume of the donor; and execute a blood separation procedure.

In another aspect, there is a blood processing device which includes a separator, a pump system, and a controller. The controller is configured to perform at least two separate total blood volume calculations based on inputted donor characteristics to produce at least a first total blood volume and a second total blood volume, select the largest total blood volume as the maximum total blood volume of the donor, and execute a blood separation procedure.

Brief Description of the Drawings

Fig. 1 is a is a perspective view of an exemplary commercial blood separation device;

Fig. 2 is a diagrammatic view of an exemplary disposable fluid flow circuit that may be used in combination with the blood separation device of Fig. 1 ;

Fig. 3 is a side elevation view, with portions broken away and in section, of the blood separation device of Fig. 1 , with a centrifuge bowl and spool of the device being shown in their operating position and with the fluid flow circuit of Fig. 2 mounted thereon; Fig. 4 is a flow chart illustrating the steps of a method in accordance with the present application;

Fig. 5 is a graph showing results of four different total blood volume calculation methods;

Fig. 6 is a graph showing results of four different total blood volume calculation methods along with a plot of the minimum total blood volumes for each weight; and

Fig. 7 is a graph showing results of four different total blood volume calculation methods along with a plot of the maximum total blood volumes for each weight.

Description of the Illustrated Embodiments

The embodiments disclosed herein are for the purpose of providing a description of the present subject matter, and it is understood that the subject matter may be embodied in various other forms and combinations not shown in detail. Therefore, specific designs and features disclosed herein are not to be interpreted as limiting the subject matter as defined in the accompanying claims.

Methods for determining total blood volume of a donor can be utilized by a variety of devices. Specifically, various blood processing devices and systems can utilize the method/algorithm described. The method/algorithm can be applicable to any hematology or pathology medical device. Any medical procedure requiring removal or addition of any amount of fluid to a donor or patient could apply the method. Specifically, the method/algorithm may be applied in centrifugal and filtration separation devices. It should be understood that the illustrated blood separation device and fluid flow circuit provided are merely exemplary and that the principles described herein may be practiced with a variety of differently configured blood processing devices and fluid flow circuits. The blood processing device must only be programmed with the disclosed algorithm and include a controller for executing the algorithm.

For example purposes only, the use of the claimed algorithm/method of determining total blood volume for a donor will be shown and described in conjunction with a centrifugal blood separation device. Centrifugal blood separation devices are known in the art and currently practiced commercially. One known separation device is shown in Figs. 1 -3. Fig. 1 shows an exemplary commercial centrifugal blood separation device 10 that may be used in combination with a disposable fluid flow circuit 12 (Fig. 2) to comprise a blood processing system (Fig. 3) for separating blood into two or more components. The illustrated blood separation device 10 is currently marketed as the AMICUS® separator by Fenwal, Inc. of Lake Zurich, Illinois, which is an affiliate of Fresenius Kabi AG of Bad Homburg, Germany, and is described in greater detail in U.S. Patent No. 5,868,696, which is hereby incorporated herein by reference. The device 10 can be used for processing various fluids, but is particularly well suited for processing whole blood, blood components, or other suspensions of biological cellular materials.

The device 10 includes a separator configured as a centrifuge 14 (Fig. 3) used to centrifugally separate blood components. The device 10 may be programmed to separate blood into a variety of components and sub-components. For example, in an exemplary blood separation procedure, the centrifuge 14 is operated to separate whole blood into platelet-rich plasma and red blood cells, with the platelet-rich plasma then being separated into platelet-poor plasma and platelets or platelet concentrate.

The illustrated centrifuge 14 is of the type shown in U.S. Patent No. 5,316,667, which is hereby incorporated herein by reference. The centrifuge comprises a bowl 16 and a spool 18, which are received within a bucket or enclosure 20. The bowl 16 and spool 18 are pivoted on a yoke 22 between an operating position and a loading/unloading position. When the bowl 16 and spool 18 are in the loading/unloading position, a separation chamber 26 of the flow circuit 12 is wrapped around the spool 18 and positioned within the centrifuge 14, in an annular gap defined between the bowl 16 and the spool 18. Further details of a separation chamber 26 and its operation may also be found in U.S. Patent No. 5,316,667.

Other portions of the flow circuit 12 may remain outside of the bucket 20. In the illustrated embodiment, the various tubing connected to the blood separation chamber 26 are bundled in an umbilicus 28, which extends outside of the bucket 20 during use (Fig. 3).

The tubing of the umbilicus 28 may be connected to cassettes 50A, 50B, and 50C of the flow circuit 12 (Fig. 2), which are molded components that define a plurality of fluid flow segments that may be selectively placed into and out of fluid communication with each other via the operation of valve stations defined in the cassette. A front panel 52 of the blood separation device 10 includes a plurality of cassette holders 54 (Fig. 1 ) to accommodate the cassettes 50A, 50B, and 50C of the flow circuit 12. Each cassette holder 54 receives and grips a different one of the cassettes 50A, 50B, 50C of the fluid flow circuit 12 along two opposed side edges in the desired operating position. Each cassette holder 54 includes a pair of peristaltic pump stations or pumps 56. When a cassette is gripped by the cassette holder 54, tubing loops 58 extending from the cassette (Fig. 2) make operative engagement with the pumps 56. The pumps 56 are operated under command of a system controller to cause fluid flow through the associated cassette.

The front panel 52 of the device 10 may include additional components, such as at least one optical line monitor 58. If provided, the optical line monitor 58 may receive a tubing or fluid flow conduit of the flow circuit 12 to optically monitor fluid flowing therethrough. The front panel 52 may also include various clamps 60 that receive a tubing or fluid flow conduit of the flow circuit 12 to selectively allow and prevent fluid flow through that conduit.

A user interface screen 62 (e.g., a touchscreen) may be positioned above the front panel 52 (as in Fig. 1) or at some other location. The user interface screen 62 may allow an operator to interact with the system controller (e.g., a microprocessor) of the device 10 to provide instructions to the controller (e.g., to carry out a particular procedure), as well as providing information to the controller to be used during a procedure (e.g., donor characteristics). The user interface screen 62 may provide the operator with instructions (e.g., to connect or disconnect the blood source from the flow circuit 12) and information (e.g., alerting the operator to a blockage in a fluid flow conduit of the flow circuit 12).

The device 10 includes a programmable controller which is configured to control the operation of the system. The controller may be provided as a computer or associated programmable microprocessor or other known mechanism for controlling one or more of the elements and processing information from one or more elements of the system in accordance with the procedure and steps set forth herein.

The controller may be coupled to one or more of the structures of the device 10, for example to receive information (e.g., in the form of signals) from these structures or to provide commands (e.g., in the form of signals) to these structures to control the operation of the structures. The controller may be coupled to pumps, and the drive or separator to provide commands to those devices to control their operation. The controller may be directly electrically connected to these structures to be coupled to them, or the controller may be directly connected to other intermediate equipment that is directly connected to these structures to be coupled to them. The controller may also be wirelessly connected to any of these devices.

Using the user interface screen 62, a phlebotomist or operator may enter parameters and information relevant to the blood processing procedure. This information can include patient measurements such as height, weight, hematocrit, or characteristics such as gender, previous donation reactions, or any other relevant information. The controller may use these measurements to perform calculations for values such as total blood volume of the donor. Hence, while it may be described herein that a particular component of the system performs a particular function, it should be understood that that component is being controlled by the controller to perform that function.

As noted, the various components of the fluid flow circuit 12 may be connected by flexible tubing or any other suitable fluid flow conduit. The illustrated flow circuit 12 is a “two needle” system, which includes a pair of blood source access devices 64 and 66 (e.g., phlebotomy needles), with one serving to draw blood into the flow circuit 12 from a source, while the other serves to return fluid to the source. In other embodiments, the flow circuit may be configured as a “single needle” system in which a single blood source access device (e.g., a phlebotomy needle) is used to both draw blood from a blood source and convey fluid to the blood source.

The separator of the blood processing device may also be a spinning membrane separator. PCT Patent Application Publication No. WO 2012/125457 A1 , which is hereby incorporated by reference herein, describes an exemplary spinning membrane separator that would be suitable for incorporation into the fluid flow circuit 12, but it should be understood that the spinning membrane separator and the matching spinning membrane separator drive unit may be differently configured without departing from the scope of the present disclosure. Exemplary spinning membrane systems which may utilize the method/algorithm include Aurora™ and Aurora™ Xi by Fenwal, Inc. of Lake Zurich, Illinois, which is an affiliate of Fresenius Kabi AG of Bad Homburg, Germany.

Regardless of the particular configuration of the blood separation device 10, the separator, and the controller, the controller is configured and/or programmed to execute at least one blood processing application but, more advantageously, is configured and/or programmed to execute a variety of different blood processing applications. In any of these procedures, it is important to know the total amount of blood from blood source in order to achieve the goals of the procedure (e.g., collecting a particular volume of a blood component).

To begin a separation procedure, an operator may select (e.g., using the user interface screen 62) the procedure from among the variety of procedures that the device 10 is capable of performing. The operator may enter a variety of information requested by the system controller that allows the controller to better carry out the procedure.

For example, in an exemplary procedure, the blood separation device 10 is used to collect platelets from a blood source. It should be understood that the following procedure is merely exemplary and that the principles described herein may be employed in collecting other blood components (e.g., red blood cells, mononuclear cells, or plasma).

An exemplary method for determining minimum total blood volume or maximum total blood volume is then executed, as shown in Fig. 4. Donor specific characteristics may be entered into the controller by the operator using the interactive screen 62, as shown in block 100. Alternatively, the donor-specific characteristics may be provided to the controller through a data management system that includes a data base including such information.

The donor specific characteristics may include any relevant characteristics, depending on the procedure and the calculations being used for total blood volume. The characteristics may include height and/or weight. Donor hematocrit may also be entered. The biological gender of the donor may also be entered, but if the gender is not known, it does not necessarily need to be considered in the calculation. The controller then uses the data provided by an operator to calculate the total blood volume for the donor by a set number of approaches or calculations, as in block 200 of Fig. 4. The number of calculations may be at least two, but may be three calculations or four calculations or more. Each total blood volume calculation may be based on any suitable data and may be determined or selected based on any suitable approach.

If only a donor’s weight is known, a linear approximation method may be used. In this instance, TBV=y + (x)*Weight. The intercept (y) and the slope (x) are empirically derived and can be set by a user or controller.

When the donor’s weight and a hematocrit value are the only donor-specific characteristics used, a three-tier nomogram, such as the FDA nomogram , can be adopted, in which three different weight classes of donors are utilized (between 1 10 lbs. and 149 lbs., between 150 lbs. and 174 lbs., and 175 lbs. and up).

Alternatively, a donor’s total blood volume may be determined using the donor’s weight and height, by using, for example the Lemmens formula, in which the total blood volume is based on the BMI (Body Mass Index) of the donor (TBV = r- -

70/ if— ) ). See, “Estimating Blood Volume in Obese and Morbidly Obese Patients,” \ V 2

Lemmens et aL, Obesity Surgery 16, 2006 , pp. 773-776.

In a further alternative, a donor’s total blood volume may be determined using the donor’s weight, height, and gender, by using, for example, the Nadler equations. TBV = (0.3669 * Ht³) + (0.03219 * Wt.) + 0.6041 for Males and TBV = (0.3561 * Ht³) + (0.03308 * Wt.) + 0.1833 for Females, where Ht is in meters and Wt. is in kilograms. [001] Additionally, a donor’s total blood volume may be determined using the donor’s weight and gender by using, for example the Feldschuh equation. TBV=weight (Kg)* ratio (mL/Kg). The ratio is specific to the donor’s gender with the male ratio as 72.5 mL/Kg and the female ratio as 66.3 mL/Kg.

The total blood volume may also be based on, for example, Gilcher’s Rule of Five (that takes into account sex, weight and morphology (obese, thin, normal or muscular), or the standards of the International Counsel for Standardization in Haematology (“ICSH) as set forth in Br. J. Haem. 1995, 89:748-56) (that consider the height, weight, age, and sex of the donor), or any other method consistent with the safety and comfort of the donor. As can be appreciated, the methodologies for determining total blood volume described above are exemplary. Any other generally accepted methodology for determining donor’s total blood volume may also be used, such as any of those described in US 2020/0147289 or US 2021/0282684, which are incorporated herein by reference.

The operator or controller then decides if the total blood volume should be the minimum or maximum total blood volume, as shown in block 300 of Fig. 4. The system applying the adaptive blood volume algorithm, may have a setting dictating use of either the minimum or maximum blood volume output. The setting can also be dictated by the operator. Afterward, depending on the setting of operator input, line 300a or 300b can be followed. Line 300a resulting in a calculation of minimum blood volume 310, by selecting the lowest total blood volume for a particular measurement (such as weight). Line 300b resulting in a calculation of maximum total blood volume 320, by selecting the largest total blood volume for a particular measurement (such as weight).

The graph in Figure 5 displays the output of four different blood volume methods according to varying weights of people of a constant height. The height used was 66 inches, or 1 .6764 meters. These methods may be any of the described methods or any acceptable method for estimating the volume of blood in a person without departing from scope. In this particular example, method 1 is a linear approximation model with the equation TBV=950 + 44.092*Weight. The intercept and slope of the equation are empirically derived. Method 2 is the Nadler Female equation. Method 3 is the Lemmens equation. Finally, method 4 is the Nadler male equation. Although four different methods are used in the example, the number of methods applied may also vary without departing from scope. The method or algorithm requires at least two methods of calculating. However, three, four, or any other number greater than two can be used. As shown in Figure 5, the blood volume predictions of the four methods intersect at various weights, causing different methods to predict a minimum or maximum blood volume at different weights. The table below shows the calculated total blood volume (in mL) from each method and a comparison of the minimum and maximum blood volume results across a particular weight. Table 1

For a procedure which requires a conservative approach towards extracorporeal fluid volumes, finding the minimum of the predicted blood volumes from the different methods may be preferred as exemplified by the circles in Figure 6. In this example, the proposed adaptive algorithm finds the minimum from the four predicted blood volumes at each weight, using Method 1 from 50 kg to 86 kg, Method

2 from 86 kg to 138 kg, and Method 3 from 138 kg to 150 kg .

For a procedure which requires an aggressive approach towards maximizing product volumes (ex: plasma), finding the maximum of the predicted blood volumes from the different methods may be preferred as exemplified by the crosses in Figure 7. In this example, the proposed adaptive algorithm finds the maximum from the four predicted blood volumes at each weight, using Method 4 from 50 kg to 59 kg, Method

3 from 59 kg to 86 kg, back to Method 4 from 88 kg to 116 kg, and Method 2 from 116 kg to 152 kg.

After calculating the minimum total blood volume or maximum total blood volume and attaching a donor to the device, the controller can then proceed with initiating the blood processing procedure.

When the system controller has received all of the necessary input, performed the necessary preliminary calculations and status checks (e.g., to confirm that the flow circuit 12 is properly installed and that the various components of the device 10 are functioning properly), and primed the flow circuit 12, the separation procedure may begin.

By way of example, when the blood component to be collected is platelets, the system controller instructs one or more of the pumps 56 to draw blood from the blood source into the flow circuit 12 via one of the blood source access devices 64. The blood enters the first stage 40 of the separation chamber 26 via the inlet port 32 as the centrifuge 14 rotates the chamber 26 about a rotational axis at a sufficient speed so that the blood is separated into red blood cells (i.e., the high-density blood component) and platelet-rich plasma (i.e., the low-density blood component). The red blood cells are returned to the blood source via the outlet port, while the plateletrich plasma is conveyed out of the first stage 40 via the outlet port and into the second stage 42 via the inlet port. In the second stage 42, the platelet-rich plasma is separated into platelet-poor plasma and platelets or platelet concentrate. The platelet-poor plasma is removed from the second stage 42 and may be returned to the blood source via the outlet port 36, leaving the platelets/platelet concentrate to accumulate in the second stage 42 for eventual transfer to a collection container 86.

Blood draw and separation continue until they are ended by the system controller. The platelets/platelet concentrate accumulating in the second stage 42 are then harvested or collected, followed by a reinfusion stage in which the fluid that remains in the chamber 26 (including the buffy coat) is returned to the blood source.

It will be understood that the embodiments described 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 those combinations of features that are individually disclosed or claimed herein. For these reasons, the scope of the claims is not limited to the above-description, but is set forth in the following claims.

Aspects

Aspect 1 . A method, comprising: a method for determining minimum total blood volume of a donor for a blood processing procedure, using a blood processing device including a controller, comprising: (a) inputting at least one donor characteristic for a donor; (b) performing at least two separate total blood volume calculations to produce at least a first total blood volume and a second total blood volume; and (c) selecting the lowest total blood volume as the minimum total blood volume of the donor.

Aspect 2. The method of Aspect 1 , wherein the at least one donor characteristic includes height.

Aspect 3. The method of any of the preceding Aspects, wherein the at least one donor characteristic includes weight.

Aspect 4. The method of any of the preceding Aspects, wherein the at least one donor characteristic includes gender. Aspect 5. The method of any of the preceding Aspects, wherein the at least two different calculations includes at least three different calculations and produce at least a first total blood volume, a second total blood volume, and a third total blood volume.

Aspect 6. The method of any of the preceding Aspects, wherein the at least two different calculations includes at least four different calculations and produce at least a first total blood volume, a second total blood volume, a third total blood volume, and a fourth total blood volume.

Aspect 7. The method of any of the preceding Aspects, wherein the at least two different calculation methods include at least two of the group consisting of: Nadler equation, Lemmens equation, Feldschuh equation, Gilcher’s Rule of Five, a linear approximation, and the reference book method.

Aspect 8. A method for determining maximum total blood volume of a donor for a blood processing procedure, using a blood processing system including a controller, comprising: a) inputting at least one donor characteristic for a donor; b) performing at least two separate total blood volume calculations to produce at least a first total blood volume and a second total blood volume; and c) selecting the largest total blood volume as the maximum total blood volume of the donor.

Aspect 9. The method of Aspect 8, wherein the at least one donor characteristic includes height.

Aspect 10. The method of any of Aspects 8-9, wherein the at least one donor characteristic includes weight.

Aspect 1 1 . The method of any of Aspects 8-10, wherein the at least one donor characteristic includes gender.

Aspect 12. The method of any of Aspects 8-11 , wherein the at least two different calculations includes at least three different calculations and produce at least a first total blood volume, a second total blood volume, and a third total blood volume.

Aspect 13. The method of any of Aspects 8-12, wherein the at least two different calculations includes at least four different calculations and produce at least a first total blood volume, a second total blood volume, a third total blood volume, and a fourth total blood volume. Aspect 14. The method of any of Aspects 8-13, wherein the at least two different calculation methods include at least two of the group consisting of: Nadler equation, Lemmens equation, Feldschuh equation, Gilcher’s Rule of Five, a linear approximation, and the reference book method.

Aspect 15. A blood processing device comprising: a separator; a pump system; and a controller; the controller configured to: (a) perform at least two separate total blood volume calculations based on inputted donor characteristics to produce at least a first total blood volume and a second total blood volume; (b) select the lowest total blood volume as the minimum total blood volume of the donor; and (c) execute a blood separation procedure.

Aspect 16. A blood processing device comprising: a separator; a pump system; and a controller; the controller configured to: (a) perform at least two separate total blood volume calculations based on inputted donor characteristics to produce at least a first total blood volume and a second total blood volume; (b) select the largest total blood volume as the maximum total blood volume of the donor; and (c) execute a blood separation procedure.

It will be understood that the embodiments described above 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 those combinations of features that are individually disclosed or claimed herein. For these reasons, the scope hereof is not limited to the above description but is as set forth in the following claims, and it is understood that claims may be directed to the features hereof, including as combinations of features that are individually disclosed or claimed herein.

Claims

1 . A method for determining minimum total blood volume of a donor for a blood processing procedure, using a blood processing device including a controller, comprising: a) inputting at least one donor characteristic for a donor; b) performing at least two separate total blood volume calculations to produce at least a first total blood volume and a second total blood volume; and c) selecting the lowest total blood volume as the minimum total blood volume of the donor.

2. The method of claim 1 , wherein the at least one donor characteristic includes height.

3. The method of any of the preceding claims, wherein the at least one donor characteristic includes weight.

4. The method of any of the preceding claims, wherein the at least one donor characteristic includes gender.

5. The method of any of the preceding claims, wherein the at least two different calculations includes at least three different calculations and produce at least a first total blood volume, a second total blood volume, and a third total blood volume.

6. The method of any of the preceding claims, wherein the at least two different calculations includes at least four different calculations and produce at least a first total blood volume, a second total blood volume, a third total blood volume, and a fourth total blood volume.

7. The method of any of the preceding claims, wherein the at least two different calculation methods include at least two of the group consisting of: Nadler equation, Lemmens equation, Feldschuh equation, Gilcher’s Rule of Five, a linear approximation, and the reference book method.

8. A method for determining maximum total blood volume of a donor for a blood processing procedure, using a blood processing system including a controller, comprising: a) inputting at least one donor characteristic for a donor; b) performing at least two separate total blood volume calculations to produce at least a first total blood volume and a second total blood volume; and c) selecting the largest total blood volume as the maximum total blood volume of the donor.

9. The method of claim 8, wherein the at least one donor characteristic includes height.

10. The method of any of claims 8-9, wherein the at least one donor characteristic includes weight.

11 . The method of any of claims 8-10, wherein the at least one donor characteristic includes gender.

12. The method of any of claims 8-11 , wherein the at least two different calculations includes at least three different calculations and produce at least a first total blood volume, a second total blood volume, and a third total blood volume.

13. The method of any of claims 8-12, wherein the at least two different calculations includes at least four different calculations and produce at least a first total blood volume, a second total blood volume, a third total blood volume, and a fourth total blood volume.

14. The method of any of claims 8-13, wherein the at least two different calculation methods include at least two of the group consisting of: Nadler equation, Lemmens equation, Feldschuh equation, Gilcher’s Rule of Five, a linear approximation, and the reference book method.

15. A blood processing device comprising: a separator; a pump system; and a controller; the controller configured to: a) perform at least two separate total blood volume calculations based on inputted donor characteristics to produce at least a first total blood volume and a second total blood volume; b) select the lowest total blood volume as the minimum total blood volume of the donor; and c) execute a blood separation procedure.

16. A blood processing device comprising: a separator; a pump system; and a controller; the controller configured to: a) perform at least two separate total blood volume calculations based on inputted donor characteristics to produce at least a first total blood volume and a second total blood volume; b) select the largest total blood volume as the maximum total blood volume of the donor; and c) execute a blood separation procedure.