CA1306727C

CA1306727C - Plasma collection set and method

Info

Publication number: CA1306727C
Application number: CA000557693A
Authority: CA
Inventors: John T. Foley; Joseph C. West, Jr.; Richard I. Brown; David E. Cerny
Original assignee: Baxter International Inc
Current assignee: Baxter International Inc
Priority date: 1987-01-30
Filing date: 1988-01-29
Publication date: 1992-08-25
Anticipated expiration: 2009-08-25
Also published as: US4806252A; DE3876886T2; WO1988005690A1; EP0301077A1; JP2796821B2; EP0301077A4; JPH01502488A; DE3876886D1; EP0301077B1

Abstract

Abstract of the Disclosure An apparatus and method of separating a component from a collected quantity of fluid. The apparatus includes a dual member centrifuge and an associated fluid flow transfer set. The transfer set has a collection container in which a quantity of fluid can be initially accumulated. The collection container is formed as a disk-shaped plastic member with an elongated generally radially extending barrier member formed therein. A component collection container is in fluid flow communication with the disk-shaped container. The method provides for centrifugation of the collection container in the dual member centrifuge thereby separating out the selected fluid component. The component can then be pumped out of the collection container into the component accumulation container. The residual fluid can be sealed in the collection container for later use. The component collection container can be separated and sealed also for later use.

Description

~3~ 2~

PLASMA COLLECTION SET AND METHOD
Technical Field of the Invention The invention pertains ~o the field of plasma rollection. More particularly, the invention pertains to the collection of plasma from volun~eer donors at temporary sites, remote from medical ~acilikies, with portable lightweight equipment capable of easy transpor~.
Back~round of the Invention The collection of blood from volunteer donors has become a very successful and very refined activity. The development of single needle, single use, disposable blood collection sets has provided a safe, relatively inexpensive and donor comfortable medium for use in the blood ollection process. Such sets haYe made possible large-scale collection of blood from volunteer donors at sites such as church halls, schools or offices which might be remote from medical facilities. The availability of volunteer donors is im~ortant in that such donvrs tend to be relatively healthy. In addition, they provide a potentially much larger reservoir of dona~able blood than i5 available rom the available group of paid donors~
In recent years, the processing o whole blood collected from donors has come to routinely include separating the blood into therapeutic components. These components include red blood cells, platelets and plasma. Various techniques and apparatus have been developed to facilitate the collection of whole blood and the subsequent separation of therapeutic components therefrom~
The collection of plasma from volunteer donors, as opposed to the collec~ion of whole blood~
has not been nearly as successful. As a result, much ~k ~3~?~72~
. -2-of the plasma now collected comes from paid donors, as opposed to volunteer donors. It would be very desirable to be able to upgrade the collection of plasma so that it becomes a volunteer based activity S to a much greater extent than it is currently.
One concideration in the collec~ion and pLocessing of whole blood is the requirement that the collecting ~nd the processing take place under s~erile conditions. A second consideration involves the requirement that processing take place under conditions that maximize the storage life of the blood components. Unless the processing take~ place within a single sealed system, the permitted storage duration and usable lifetime of the blood components is substantially shortenedr Components processed within a sealed system can be stored for four to six weeks or longer before use. On the other hand, whole blood or components thereof must be used within 24 hours if the system seal is broken.
One for~ of processing of whole blood into various therapeutic components includes centrifuging the blood so as to bring about the desired separation of those components.
To promote the desired ends of sterile processing within a single sealed system, dual member centrifuges c~n be used. One example of this ~ype of centrifuge i5 disclosed in United States Patent No.
Re. 29,738 to Adams entitled "Apparatus for Providing Energy Communication Between a Moving and a Stationary Terminal~" As is now well known, due to the characteristics of such dual member centrifuges, it is possible to rotate a container containing a fluid, such as a unit of donated blood, and to withdraw a separated fluid component, such ~s plasma, into a stationary container, outside of the ~3~t~2~7 centrifuge without using rotating seals. Such container systems can be formed as closed, sterile transfer sets.
The Adams patent discloses a centrifuge having an outer rotatable member and an inner rotatable member. The inner member is positioned wi~hin and rotatably supported by the outer member~
The outer member rotates at one rotational velocity, usually called one omega, and the inner rotatable member rotates at twice the rotational velocity of the outer housing or two omega. There is thus a one omega difference in rotational speed of the two members. For purposes of this document, the term ~dual member centrifuge~ shall refer to centrifuges of the Adams type.
The dual member centrifuge of the Adams patent is particularly advantageous in that, a~ noted above no seals are needed between the container of fluid being rotated and the non-moving component ~0 collection container. The system of the Adams patent, provides a way to process blood into components in a single, sealed t sterile sy~tem wherein whole blood from a donor can be infused into the centrifuge while the two members of the centrifuge are being rotated.
An alternate to the apparatus of ~he ~dams patent is illustrated in United States Patent No.
4,056,224 to Lolachi entitled "Flow System for Centrifugal Liquid Processing Apparatus.~ The system of the Lolachi patent includes a dual member centrifuge of the Adams typeO The outer member of the Lolachi centrifuge is ro~ated by a single electric motor which is coupled to the internal rotatable housing by belts and shafts.

~3~ 7 United States Patent No. 4,108,353 to Brown entitled "Centrifugal Apparatus With Oppositely Positioned Rotational Support Means" discloses a centrifuge structure of the Adams type which includes two separate electrical motors. One electric motor is coupled by a belt to the outer member and rotates the outer member at a desired nominal rotational velocity.
The second motor is carried within the rotating exterior member and rotates the inner member at the desired higher velocity, twice that of the ~xterior member.
United States Patent No. 4,109,~55 to Brown et al.
entitled "Drive System For Centrifugal Processing Apparatus" discloses yet another drive system. The system of the Brown et al. patent has an outer shaft, affixQd to the outer member for rotating the outer member at a selected velocity. An inner shaft, coaxial with the outer shaft, is coupled to the inner member.
The inner shaft rotates the inner member at twice the rotational velocity as the outer member. A similar system is disclosed in United States Patent No.
4,109,854 to Brown entitled "Centrifugal Apparatus With Outer Enclosure".
Centrifuges of the type disclosed in the above identi~ied Brown et al. and Brown patents can be utilized in combination with a sealed fluid ~low trans~er set of the type disclo~ed in United States Patent No. 4,379,452 to DeVries. The set of the DeVries patent incorporates a blood collection container that has a somewhat rectangular shape similar to those of standard blood collection sets. One embodiment of this combi.ned system is the CS3000 cell separator ~ystem marketed by Travenol Laboratories, Inc.
The CS3000 incorporates a dual member centrifuge in combination with a sealed set of the type disclosed in DeVries. This is a continuous pheresis system that 6~2'~

requires the donor to receive two needle punctures.
Such systems have been extensively used in blood centers for plasma and platelet pheresis.
The CS3000 is a large and expensive unit that is not intended to be portable. Further, the DeVries type transfer sets are quite complex to install and use.
They are also an order of magnitude more expensive than a standard, multi-container blood collection set.
A further alternate to the Adams structure i5 10 illustrated in United States Patent No. 4,530,691 to Brown entitled "Centrifuge With Movable Mandrel". The centrifuge of this latter Brown patent also is of the Adams-type. However, this latter centrifuge has an exterior member which is hinged for easy opening. When the hinged upper section is pivoted away from the bottom section, it carries the rotatable inner member along with it.
The inner member supports a receiving chamber with a spring biased mandrel which continually presses against a sealed, blood containing, container positioned within the receiving chamber. The system of this latter Brown patent also discloses the use of two separate el~ctric motors to rotate the inner and outer members.
The motors are coupled to a control system.
Another continuous centrifuge based system is di~closed in Judson et al. United States Patent No.
3,655,123 entitled "Continuous Flow Blood Separator~.
The system of the Judson et al. patent uses two needles, an outflow needle and an inflow needleO Whole blood is drawn from a donor via the outflow needle~ The whole blood fills a buffer bag. Blood from the buffer bag drains, under the force of gravity into a centrifuge.
The system of the Judson et al. patent uses the centrifuge to separate blood components. The plasma can be collected in a container. The red blood cells can be xeturned to the donor via the inflow needle. The ~ ,.

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system of the Judson et al. patent does not use a dual member centrifuge. The system of khe Judson et al.
patent does not appear to be readily portable.
There thus continues to be a need for a method and related apparatus of plasmapheresis which can readily be used with volunteer donors at various temporary locations. This method and related apparatus should be usable by technicians with a level os skill commensurate with the level of skill now found at volunteer-based blood collection centers. Further, both the method and related apparatus should be readily portable to locations such as churches or schools where blood collection centers are temporarily established. Preferably the apparatus will be essentially self-contained.
Preferably, the equipment needed to practice the method will be relatively inexpensive and the blood contacting set will be disposable each time the plasma has been collected from a single donor.
Summary_of the Invention Various aspects of the invention are as follows:
A method of separating a selected component from a fluid within a sealed system, a collection container of which is rotated in a centrifuge while another portion of which remains stationary, the method comprising, providing a centrifuge, providing a sealed fluid collection system with a ~luid filLed collection container having an interior collection volume into which extends a selectively oriented barrier member, inserting the fluid filled collection container into a receiving chamber of the centrifuge, rotating the collection container at a predetermined rotational velocity thereby separating the selected component from the remaining fluid in the container by forcing the remaining fluid into an outer annular region adjacent a rotating peripheral wall of the chamber while simultaneously collecting the separated component in an inner, ad~acent annular region thereby emptying a central region of the container, reducing the rotational velocity of the .~,............ ' t7~'~

6a collection container and fluid therein and blocking movement o~ the fluid in the container with respect t.hereto by means of the barrier member so as to minimize mixing of the separated selected component with the remaining ~luid, and withdrawing a selected portion of fluid from the rotating collection container and into the stationary portion of the system.
A method of separating first and second selected components from a quantity of fluid comprising, providing a fluid flow transfer sat having first and second disk-shaped containers in fluid flow communication and a third container in fluid flow communication with the first and second containers, providing a centrifuge, filling the first disk-shaped container with a predetermined quantity of fluid, placing the first and second containers in a rotatable receiving chamber of the centrifuge, interposing a radially extending barrier into the first container, rotating the chamber so as to effect separation of the first and second components from a residual fluid component, withdrawing the first and : second separated components from the first disk-shaped container without remixing them with the residual ~luid component and at least partially filling the second disk-shaped container with same, rotating the receiviny chamber and separating the first and second components from one another, and withdrawing one of the separated components from the second disk shaped container into the third container.
A fluid collection set, usable in the collection of a quantity of fluid, and positionable in part in a receiving chamber of a centrifuge ~or the purpose of separating, by centrifugation, a selected fluid component, the set comprising, a flexible, disk-shaped collection container defining an interior collection volume in which a quantity of fluid can be collected with said collection container having a selectively curved, sealed periphery, a fluid flow conduit with a proximal end and a distal end, said proximal end in fluid flow .:

~3a~
6b communication with said interior collection volume, a separated component container in fluid flow communication with said distal end of said conduit with said disk-shaped collection container rotatabl~ in the receivingchamber while simultaneously coupled to said compo~ent container so as to accumulate the component separated from the quantity of fluid rotated in the receiving chamber with said proximal end of said fluid flow conduit extending into said interior collection volume a predetermined amount thereby forming an elongated, radially extending barrier.
A fluid collection set, usable in the collection of : a quantity of fluid, and positionabl~ in part in a receiving chamber of a centrifuge for the purpose of separating, by centrifugation, a selected fluid component, the set comprising, a flexible, disk-shaped collection container defining ~n interior collection volume in which a quantity of fluid can be collected with said collection container having a selectively curved, sealed periphery said collection container formed of first and second planar plastic members sealingly joined along said curved periphery, a fluid flow conduit with a proximal end and a distal end, said proximal end in fluid flow communication with said interior collection volume, a separated component container in fluid flow communication with said distal end of said conduit with said disk-shaped collection container rotatable in the receiving chamber while simultaneously coupled to said component container so as to accumulate the component separated ~rom the quantity of fluid rotated in the receiving chamber with said proximal end of said fluid flow conduit extending into said collection container through a selected region of said circular periphery.
16. A fluid collection set, usable in the collection of a quantity of whole blood, and positionable in part in a receiving chamber of a centriXuge for the purpose of separating, by centrifugation, a selected blood component, the set comprising, a flexible, plastic, disk-~6~7Z~7 6c shaped collection container defining an interior collection volume in which a quantity of whole blood ~rom a donor can be collected with said collection container having a curved periphery, a fluid flow conduit with a proximal end and a distal end, said proximal end in fluid flow communication with said interior collection volume, a separated component container in fluid flow communication with said distal end of said conduit with said disk-shaped collection container rotatable in the receiving chamber while simultaneously coupled to said component container so as to accumulate the component separated from the quantity of blood rotated in the receiving chamber with said proximal end of said fluid flow conduit extending into said collection volume a predetermined amount and attached to a region of the collection container thereby forming a radially extending barrier member positioned within said interior collection volume.
A system for separation of a component from a fluid comprising, means for centrifugation including a rotatable receiving chamber, a fluid collection set, usable in the collection of quantity of fluid, and positionable at least in part in said receiving chamber for the purpose of separating, by centriPugation, the selected fluid component, said set inc:Luding, a flexible, disk-shaped collection container defining an interior collection volum~ in which the quantity of fluid can be collected with said collection container having a circular periphery, said collection container with the quantity of fluid positionable in said receiving chamber, a fluid flow conduit with a proximal end and a distal end, said proximal end in fluid flow communication with said interior collection volumP, a separated component container in fluid flow communication with said distal end of said conduit with said disk-shaped collection container rotatable in the receiving chamber while simultaneously coupled to said component container so as to accumulate the component separated from the quantity ~ ~3~6~7~t7 6d of fluid rotated in said receiving chamber with said collection container formed of first and second planar plastic members sealingly joined along said circular periphery, a barrier member positioned within said collection container between said sealed planar plastic members, with said proximal end of said fluid flow conduit extending into said collection volume a predetermined amount thereby forming said barrier member.
A fluid collection set, usable in the collection of a quantity of fluid, and positionable in part in a receiving chamber of a centrifuge for the purpose of separating, by centrifugation, a selected fluid component, the set comprising, a flexible, disk shaped collection container defining an interior collection volume in which a quantity of fluid can be collected with said collection container having a circular, sealed periphery, and a generally radial container wall heat seal line extending from said periphery toward a center thereof, thereby blocking circumferential fluid flow along said periphery, a fluid flow contact with a proximal end and a distal end, said proximal end in fluid flow communication with said interior collection volume, a separated component containiner in fluid flow communication with said distal end of said conduit with said disk-shaped collection container rotatable in the receiving chamber while simultaneously coupled to said component container so as to accumulate the component separated from the quantity of fluid rotated in the receiving chamber.
A fluid collection set, usable in the collection of a quantity of whole blood, and positionable in part in a receiving chamber of a centrifuge for the purpose of separating, by centrifugation, a selected blood component, the set comprising, a flexible, plastic, disk-shaped collPction container defining an interior collection volume in which a quantity of whole blood from a donor can be collected with said collection container having a circular periphery with first and second opposed `` 13t~6~'7 6e walls of said container sealed together with a generally radial heat seal line extending from a region of said circular periphery toward a center thereof to form a barrier to circumferential flow adjacent said periphery, a fluid flow circuit with a proximal end and a distal end, said proximal end in fluid flow communication with said interior collection volume, a separated component container in fluid flow communication with said distal end of said conduit with said disk-shaped collection container rotatable in the receiving chamber while simultaneously coupled to said component container so as to accumulate the component separated from the quantity of blood rotatsd in the receiving chamber.
In accordance with another aspect of the invention, a fluid collection set is provided which is usable in the collection of a quantity of fluid. The set is positionable in part in a receiving chamber of a centrifuge. By centrifugation, a selected fluid component can be separated from the fluid in the set.

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Tne set includes a flexible disk-shaped collection container. This container can be used to accumulate a quantîty of fluid. The container can have an elliptical or a circular periphery.
barrier member is positioned within the container to impede the movement of the fluid within the container during the centrifugation process.
Aiblood drawing cannula can be coupled to the container by a draw conduit. The cannula can be used to pierce the vein of a donor for the purpose of filling the container with a unit of whole blood.
A fluid flow conduit, such as a section of hollow tubing is attached at one end to the disk-shaped collection container. The second end of the conduit is attached to a second container in which the separated component is to be accumulated.
The separated component container is positionable outside of the centrifuge, at a fixed location~ while the collection container is rotated within the receiving chamber of the centrifuge.
In one embodiment of the invention, the barrier member can be formed as an elongated generally extending radial member. The collection container can be formed of firs~ and second planar plastic members which are joined, perhaps by heat sealing, along the curved periphery.
The fluid can be for example, whole blood collected from a donor. In this embodiment, the blood collection container is positioned in the receiving chamber of the dual member centrifuge. The separated component can be, for example, plasma.
Subsequent to rotating the collection container in the centrifuge, the ~eparated plasma can be pumped into a plasma collection container exter~or to the centrifuge.

6.~2t~

A method of practicing the invention includes providing a dual member centrifuge. In addition, a sealed 1uid collection system can be provided. The fluid collection system has a disk-shaped fluid collection container. The fluid collection container is filled with a q~antity of floid and ~hen is positioned within a receiving chamber of the centrifuge.
The collection container is rotated at a prede~ermined rotational velocity which results in the separation of the selected component from the remai~ing fluid in the container. During the separating step, the separated fluid fills an inner annular region within the disk-shaped container. ~n outer annular regionO adjacent the interior peripheral wall of the receiving chamber is filled with the residual fluid in the container~ A central region of the container is emptied of fluid during the centrifugation process and collapses. As a result, the container assumes a donut or toroidal shape.
The separated fluid component can then be with~rawn from the container. The withdrawing step can include pumping the separated component from the collection container into a component container.
In a preferred embodiment of the invention~
the disk-shaped container is rotated at a relatively high speed, on the order of 4~000 rpm for 7-10 minutes to effect the separ~tion. The container is then slowed during a 2 to 4 minute period tv about 1,000 rpm for the purpose of withdrawing the separated componentO During the slow-down process the generally radially extending ~arrier member within the container blocks movement or sliding of the fluid in the container with respect theretoO

:~3~ Z'7 g In yet another embodirnent, first and second components c~n be separated. The first and ~econd ~eparated components separate from the residual fluid in a two stage process. Initially, both separated components are mixed together. Over a period of time, as the receiving chamber continues to rotate, the two separated components will in turn separate from each otherO
The system o the present invention is particularly advantageous in that the donor experiences only a single needle puncture as is the case when donating blood. Furthe~, once the unit of blood has be-en drawn, the donor is finished and can leave. Finally, the transfer set should have a cost comparable to the cost of currently available blood collection sets.
Numerous other advantages and features of the present invention will become readily apparent from t~e following detailed description of t~e invention an~ the embodiments thereof, from the claims and from the accompanying drawings in which the details of the invention are fully and completely disclosed as a part of this specification.
Brief Descri~ion of the Drawin~s Figure 1 is an overall system view schematically illustrating a readily transportable dual member centrifuge and fluid flow transfer set in accordance with the present invention;
Figure 2 is a top plan view of a blood collection container in accordance with the present invention;
Figure 3 is a view in section taken ~long plane 3-3 of Figure 2 illustrating the relationship of the radially extending barrier member to the sheet member~ of the container:

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Figure 4 is a view in section taken along plane 4~4 of Figure 2 illustra~ing the relationship between the container forming sheet members and the ~irc~lar peripheral seal of the container;
Figure 5 is a schematic view illustrating an alternate fluid flow transfer set in accordance with the present invention;
Figure ~ is a enlarged view, partly in section, ~f the receiving chamber of the centrifuge of Figure 1 illustrating separation of a component from a fluid in accordance with the present invention;
Figure 7 is an enlarged view, partly in section o~ an alternate structure also illustrating separation of a componen from a fluid in accordance with the present invention;
Figure 8 illustrates schematically the steps of a method of separating a fluid component in accordance with the present invention; and Figure 9 is an overall schematic view of an alternate fluid flow transfer set and method of separating first and second fluid components in accordance with the present invention.
Detailed Descr ~ he Prefexred Embodiment While this invention is susceptible of embodiment in many different forms, there are shown in the drawing and will be described herein in detail specific embodiments thereof with the understanding that the present disclosure i5 to be considered as an exemplification of the principles of the invention and is not intended to limit the invention to the specific embodiments illustrated.
Figure 1 illustrates a readily transportable system 10 in accordance with the present invention.
The system 10 includes a relatively light weight dual '7 member centrifuge 12 and an associated fluid flow transfer set 14.
The dual member centrifuge 12 is of the Adams type having a stationary support 20 on which is mounted a first motor 22. The first motor 22 has a rotary output shaft 24 which rotates at a first angular velocity conventionally referred to as one omega. Fixedly attached to the rotary shaft 24 is a yoke 26. The yoke 26 supports a second electric motor 28. The electric motor 28 has a rotary output shaft 30. The chaft 30 rotates at an angular velocity twice that of the shaft 249 conventionally referred to as two omega~ The motor 28 is pivotably attached to the yoke 26 at pivot poin~s 36 and 38.
Affixed to the rotating shaf~ 30 is a cylindrical receiving chamber 40. The receiving chamber 40 is rotated by the shaft 30~ The chamber 40 has a cylindrical exterior peripheral surface 40a as well as a cylindrical interior peripheral surface 40b. The chamber 40 supports and rotates a collection container 44. The chamber 40 has an inner diameter on the order of six inches and an internal length on the order of two inches.
The collection container 44 is in fluid flow communication via a flexible conduit 46 with the remainder of the set 14. A proximal end 48 of the flexible fluid flow conduit 46 extends into the interior volu~e 50 of the containeL 44. The container 40 can be filled with a quantity of fluid 30 such as whole blood provided by a donor.
The fluid flow conduit 46 is supported by a stationary torque arm 52, The use of such torque arms is well known ~o tAose skilled in the ar~ wi~h respect to dual member centrifuges of the Adam~

~3~2~7 type. A distal end 54 of the fluid flow conduit 46 is coupled to a "y" junction member 580 A branch ronduit 60 coupled to the junction member 58 is physically coupled to a separated component pump 62.
The separated component could, for example, be plasma and the pump 62 could be a plasma pump. The fluid frow conduit 60 is also in fluid flow communication with a sepa~ated component collection container 64.
The container 64 could be a standard plasma collection container.
Also coupled to the junction member 58 is a third fluid flow conduit 68. The ~luid flow conduit 68 is coupled to a red cell nutrient and preservative ~olution container 70. The solution in the container 70 is of a known type which provides nutrients to packed red blood cells subsequent to the plasma pheresis process. Contents of such solutions include dextrose, sodium chloride, mannitol and adenine. One appropriate solution is marketed by Travenol Laboratories, In~. under the trademark ADSOL. The container 70 is sealed with a frangible member 72 which can be broken at an appropriate point in the plasma pheresis process.
The ~ystem 10 also includes a control system 76 which i5 coupled to the motors 22 and 2B. The control system 76 receives feedback from vibration and fluid leak sensors 78 and 80. The sensots 7B and 80 are fixedly supported by a stationary suspension system 82. The ~ystem 82 can be connected to resilient members 84 to s~abilize the centrifuge 12 during operation.
In addition, if desired, a plasma interface sensor 86 can be provided which is in turn coupled to the control system 76. The plasma interfa~e ~ensor 86 can be used to detect the location o the ':`. l ~3~'2~7 interface between the separated plasma and packed red blood cells in the container 44 during the centrifugation process. An appropriate interface is disclosed in co-pending United States Patent No.
4,806,~52 entitled OPTICAL DATA COLLECTION APPARATUS
~D METHOD assigned to the assignee of ~he present invention.
As an alternate, the dual member centrifuge 12 can sense the presence of the plasma/red blood cell lo interface in the tubing member 46 to 60. For example, a source of radiant energy 88 could be attached to the stationary torque arm 52. A sensing member 90 can also attach to the stationary torque arm 52 displaced ~rom the source 88. The conduit 46 extends between the source 88 and the sensor 90. The sensor 90 detects a plasma and packed red blood c~ll interface in the flexible conduit 46 and the plasma in being pumped off by the pump 62. A signal from the red blood cell sensor 90 indicating that the inter~ace has been detected is al50 coupled to the control system 76 and can terminate the plasma pheresis operation.
The source 88 and sensor 90 can also be positioned ; adjacent the tubing member 60.
Figures 2 4 illustrate the structure of the collection container 44. The collection container 4~ is disk-shaped and can be formed o~ first and second plastic sheet members 44a and 44b. Plastic sheets o the type normally used for blood collection o~ sets are usable to ~orm the container 44. The first and second plastic members 44a and 44b can be heat sealed together at a circular periphery 100. The sealing o~ the circular periphery ~00 can be brought about by .4 ' "

~.3~;P672~7 radio frequency heat sealing or by means of heated platens. Within the circular periphery 100 is defined the interior collection volume 50. The length of the diameter of the circular pe~iphery 100 is on the ~rder of 7 to 8 inches.
It will be understood, that while an esSentially circular container 44 is illustrated in Figure 2, the present invention is not limited to circular containers~ It will be understood that a disk-shaped container could also include a container with an elliptically shaped sealed periphery.
The container 44 includes an elongated, generally radially extending barrier member 102 which extends into the interior region 50. The harrier member 102 is formed by heat sealing together a region of the sheet members 44a and 44b.
The container 44 includes a port 104 which is in fluid ~low communication with the 1exible fluid flow conduit 46. The container 44 a}so includes a port 106. The port 106 is a filling port used during the draw cycle when the donor is bleeding into and filling the container 44. The port 106 is also in fluid flow communication with a fluid flow condui~ 10~. A distal end o~ the fluid flow conduit 108 can be connected to a draw cannula 110 intended to be inserted into the vein of the donor.
The container 44 also includes a dispensing port 112. The port 112 is closed with a pierceable member and can be used to subsequently dispense the 30 remaining contents in the container 44 once the pheresis process has been completed.
Figures 3 and 4 illustrate in section ~he relationship between the barrier member 102 and the sheet members 44a and 44b as well as the curved peripheal seal 100 and the sheet member 44a and 44b.

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Figure 5 illustates an overall view of the fluid flow transfer set 14. The transfer set 14 can be used to accumulate a unit of donated blood by the same blood collection technicians as now use ~tandard blood collection sets. Further, the cost of the set 14 should be comparable to th~ cost of current blood cQllection sets.
In the em~odiment of Figure 5, the circular container 44 has been replaced by an elliptical disk-shaped container 45. The container 45 includes the draw port 105 which is in ~luid flow communication with the draw conduit 108. The draw conduit 108 terminates at its free end in the cannula 110. The container 45 can be formed in the ame manner as the container 44 by heat sealing the planar sheet me~bers 45a and 45b along the elliptical periphery 114 .
The container 45 also includes ~he port 104 which is formed in the elliptically shaped peripheral wall 114. The proximal end 48 of the fluid flow conduit 46 extends ~hrough the port 104 and terminates in a section 120 in the interior volume 122 defined by the con~ainer 45. The section 120 is : formed of a hollow tubing member which is in fluid flow commurlication with the proxima:L end 48. In addition, the section 120 is sealingly attached to adjacent regions of the plastic sheet members 45a and 45b~, The sealingly attached member 120 thus forms an inwardly extending, elongated barrier analogous to the barrier 102 in the container 44. The proximal end 4~ is sealed by a breakable cannula member 124 until the draw cycle has been completed~ The proximal end 48 can be fixedly attached to the exterior ~f the sheet member 45b at a suppor~ing weld 126.

.~3~ 7 A bushing 128 can be provided to slideably engage the stationary ~orque arm 52 to prevent abrasion and wearing vf the ~onduit 46 during the centrifugation process. In addition, the source of radiant Pnergy 8& and respective sensor 90 could be positioned-adjacent a transparent region 130 of the tubing member 60 for the purpose of sensing the plasma/packed red blood cell interface at the end of the pheresis processO Pump segment keepers 132 can al~o be provided to restrain tllbing members 60 and 68 in position with respect ~o pumps such as the plasma pump 62 which could for example be A peristalic pump.
Figure 6 illustrates the sys~em 10, and more particularly the receiving chamber 40 with ~luid filled container 44 therein partway through the centrifugation process. The centrifugation process takes on the order of 7-10 minutes at a speed of about 4,000 rpm. During this time, the whole blood in the container 44 is essentially separated into two major components.
The heavier red blood cells accumulate in an exterior annular region 140 adjacen~ the interior peripheral wall 4Ob. Platelet poor plasma collects in an interior annular region 142 as the plasma is not as heavy as the red blood cells. An interface region 144 develops between the exterior toroidal region 140 filled with packed red blood cells and the interior toroidal region filled with platelet poor plasma.
During the high speed separation interval, when the red blood cells are being forced into the outer annular region 140, a central portion 44c of the sheet member 44a i~ emptied of fluid. As a result, that region collapses, as illustrated in :~3~ 2~7 Figure S, d~e to the effects o:E centrifugal forces generated by rotation of the fluid.
After the 7 10 minute centrif~gation interval has passed, the chamber 40 can be slowed ~o about 1,000 rpm over a 2-4 minute interval. It has been found that the bar~ier 102 is important during the slow-down period to keep the ~luid within the container ~om sliding and remixing again. By means of the barrier member 102t the fluid i5 also forced to slow down at the same rate as is the receiving chamber 40. During the slow-down period, the packed red blood cells stay in the annular region 140 and the platele~ poor plasma tends to remain in the interior annular region 142.
Once ~he slow-down interval has passed, the platelet poor plasma can be withdrawn from the region 142 via the fluid flow conduit segment 120. The segment }20 extends into the region 142 through the seal 100. The member 120 in additiun to being able to function as the barrier member as discussed above, must extend far enough into the container 44 so as to be located in the region 142 of platelet poor plasma.
It should be noted that the interface 144 could contain platelets which mig}lt be drawn off 25 subsequently after the platelet poor plasma in the region 142 has be~n removed. The peristalic pump 62 can then pump the platelet poor plasma from the region 142 into the container 64.
As the platelet poor plasma is withdrawn from the region 142, the bag 44 will collapse further~ The collapsed region 44c will extend toward the interior peripheral wall 40b.
Figure 7 illustrates an alternate construction of the container 44. The proximal end 48 of ~he tubing member 46 is coupled to a plasma ~3~6~2'7 withdrawal port 150 which is centrally located. In the embodiment of Figure 7, the container illustrated therein will require a separate elongated radially extending barrier member as in Figure 2. Except for the location of the plasma withdrawal port 150, the container of Figure 7 functions essentially the same way as does the con~ainer of Figure 6.
Figure 8 illustrates a batch method of collecting platelet poor plasma in accordance with the present invention. The method of Figure 8 is suitable for use in connection with volunteer blood donation programs. The dual housing centrifuge 12 will be relatively lightweight and is easily transportable. Hence, it can be taken to the device locations such as church basements and recreation halls where blood donation programs are temporarily set up.
In Figure 8a~ a donor is illustrated donating a unit of blood B which is accumulated in the bag 4~. The bag 44 i5 intergally attached to the remainder of the set including the plasrna collection container 64. As far as the donor is concerned, this is merely a standard blood donation processO Once the unit of blood ha~ been accumulated, the donor is free to leave.
In Figure 8b the container 44 contains a unit of whole blood B and has been uncoupled from the donorO The draw conduit 108 has been sealed, for instance~ by heat sealing. The ~rangible cannula 124 has been broken so as to place the container 44 into fluid flow communication with the plasma accumulation container 64. Figure 8c illustrates the blood filled container 44 positioned in the receiving chamber 40 prior to the initiation of centrifugation.

Figure 8d illustrates the container 44 partway through the centrifugation process. In Figure 8d the red blood cells have started to fall way from the plasma into the annular region 140. The platelet poor plasma is starting ~o accumulate in the inner annu.lar region 142.
' Figure 8e illustrates the container 44 subsequent ~o the slow down s~ep and while platelet poor plasma is being withdrawn from the region 142 by means of the pump 62. The accumulated platelet poor plasma is being collected in ~he container 64. As is illustrated in Figure 8e, the central region 44c of the container 44 is collapsing~
Figure 8f illustrates the container 44 from which the platelet poor plasma has been removed or : withdrawn and after the nutrient mixture in the container 70 has been infused therein. The nutrient mixture prolongs the life of the packed red blood cells and provides a dilluting fluid to restore the hematocrit to levels such that the concentrated red blood cells can then be infused into a patient. Also in Figure 8f, the container 64 of plate~et poor plasma is illustrated sealed off and separated ~rom the container 44.
In addition to being able to accumulated platelet poor pla~ma in a collection container such - as the container 64 it is also possible, using another embodiment, to accumulate the platelets in a separate container. Figure ~ illustrates a fluid flow transfer set lS0, related apparatus and method usable for this purpose~
The transfer set 150 includes a first, disk-shaped container 152 such as the container 44 of Figure 2. The container 152 is in fluid flow 35 co~munication via a conduit 154 with a second ~3~ '7 disk-shaped container 156. The container 156 can also have a structure which corresponds to the container 44~
A tly~ junction member 160 located in the fluid flow conduit 154 provides a fluid flow path, via a conduit 162, to a container 164. Initially the c~ntainer 164 contains nutritive solution of the type noted previously with respect to the container 70.
The container 152 is initially filled with whole blood as illustrated in Figure 8a previously discussed~ The set 150 is then mounted on a dual member centriruge such as the centrifuge 12. The collection container 152 and the second container 156 are both loaded into the receiving chamber 40. The conduit 1S4 is brought out of the receiving chamber to a stationary region outside of the centrifuge 12 and coupled to a pump 170.
The tubing member 162 i5 initially clamped shut. The receiving chamber 40 is first rotated at about 3000 rpm for abou~ 5 minutes to separate the red blood cells in the container 152 from the platelet rich plasma. I'he receiving chamber is then slowed down to 1,000 rpm and the platelet rich plasma is pumped out of the container 152, via the conduit 154 by the pump 170 and into the second container 15S.
The rotationa3. velocity of the receiving chamber is then increased to about 4,000 rpm to separate the platelets from the plasma in the container 156. Once the platelets and the plasma have been separated, the plasma forms an annularly shaped region within the container 156 and the platelets form an adjacent exterior annular region surrounding the annular region of platelet poor plasma.

3~;?'6 The clamp 172 can ~hen be opened. The nutrient solution can be drained from the container 164 in~o the packed red blood cells in the container 152. The platelet poor plasma can then be pumped out 5 of the second container 156, via the conduit 154r and into the now empty container 164r - At this time the centrifugation process can be terminated. The three containers 152, 156 and 164 ran be removed from the centrifuge 12. The container 152 can be sealed with its contents being the concentrated red blood cells with the nutritive solution added thereto. The container 156 can be sealed with it~ contents being the platelets remaining therein. Finally, the container 164 can be sealed with its contents being the platelet poor plasma.
With respect to the embodiments of Figures 6 and 7, it will be understood that ~he port to the fluid flow conduit 48 is to be located in the region of platelet poor plasma to effect withdrawal of that separated component from the disk-shaped collection container 44. It will also be understood that the particular advantage of the disk-shaped container is that it provides for self balancing vf the rot~ting collection chamber 40. Thî~ is a particularly important feature in that if the collected fluid F in the container 44 is distributed in such a ~y that the rotati~g chamber 40 is unbalanced, this will cause unnecessary wear and shorten the life of the apparatus~
Further, i~ will be understood that while the set 14 has been illustrated in combination with a dual member centrifuge 12J the invention can be : practiced without the use of a dual member ~ 35 centrifuge. For example, the entire set 14 could be 3~ ~ ~ 2 7 positioned in the rotary chamber 40. The chamber 40 could be rotated using just a single motor. In this embodiment, a plasma pump such as the parastolic pump 62 could also be located in the rotating chamber 40.
The separated platelet poor plasma could be pumped into the plasma collection container 64 after ce~trifugation has occurred. Alternately, springs could be used to force the separated plasma into a collection container. The particulax advantages of ~he disk-shaped collection chamber 44 will still be realized with these embodiments.
Further, it will be understood that the barrier member, s w h as the radially extending barrier member 102 of the container 44 provides for enhanced performance of the system~ However, the container 44 could be formed as a disk-shaped container without that barrier memberD In this event, the separated component could be kept from remixing with the residual fluid component in the container by slowing the rotating chamber 40 down very slowly. This will result in the separated component ~luid and the residual fluid tending not to slide within the container causing remixing.
Alternately, instead of an integrally formed barrier such as the barrier member 102, a barrier means can be formed by providiny the rotating chamber with clamping means. The clamping means can be provided to clamp the two sheet members 44a and 44b ~ogether in a radially extending region so as to create a barrier member which is effective to inhibik remixing within the container 44 but which is formed external to that container.
From the foregoing, it will be ob erved that numerous variations ~nd modifications may be effected wi~hout departins from the true spirit and scope of 6 ~ 2'7 the novel concept of the invention. It is to be understood that no limitation with respect to the specific apparatus illustrated herein is intended or should be inferred. It is, of course, intended to cover by the appended clai~s all such modifications as fall within the scope of the clai~s.

Claims

1. A method of separating a selected component from a fluid within a sealed system, a collection container of which is rotated in a centrifuge while another portion of which remains stationary, the method comprising:
providing a centrifuge;
providing a sealed fluid collection system with a fluid filled collection container having an interior collection volume into which extends a selectively oriented barrier member;
inserting the fluid filled collection container into a receiving chamber of the centrifuge;
rotating the collection container at a predetermined rotational velocity thereby separating the selected component from the remaining fluid in the container by forcing the remaining fluid into an outer annular region adjacent a rotating peripheral wall of the chamber while simultaneously collecting the separated component in an inner, adjacent annular region thereby emptying a central region of the container;
reducing the rotational velocity of the collection container and fluid therein and blocking movement of the fluid in the container with respect thereto by means of the barrier member so as to minimize mixing of the separated selected component with the remaining fluid;
and withdrawing a selected portion of fluid from the rotating collection container and into the stationary portion of the system.

2. A method as in claim 1 including collapsing a central portion of the collection container as the central region is emptying.

3. A method as in claim 2 including sensing the location of an interface between the separated component and the remaining fluid and initiating the withdrawing step when the interface has been sensed at a predetermined location.

4. A method as in claim 2 including rotating the collection container for a predetermined period of time before initiating the withdrawing step.

5. A method as in claim 2 wherein the withdrawn selected portion of fluid corresponds to the separated component.

6. A method as in claim 5 wherein the withdrawing step includes pumping the separated component into a stationary container of the system while continuously rotating the collection container at the reduced rotational velocity.

7. A method as in claim 1 wherein the provided centrifuge is a dual member centrifuge.

8. A method of separating first and second selected components from a quantity of fluid comprising:
providing a fluid flow transfer set having first and second disk-shaped containers in fluid flow communication and a third container in fluid flow communication with the first and second containers;
providing a centrifuge;
filling the first disk shaped container with a predetermined quantity of fluid;
placing the first and second containers in a rotatable receiving chamber of the centrifuge;
interposing a radially extending barrier into the first container;
rotating the chamber so as to effect separation of the first and second components from a residual fluid component;
withdrawing the first and second separated components from the first disk-shaped container without remixing them with the residual fluid component and at least partially filling the second disk-shaped container with same;

rotating the receiving chamber and separating the first and second components from one another; and withdrawing one of the separated components from the second disk-shaped container into the third container.

9. A method as in claim 8 including infusing a selected nutritive solution from the third container into the residual fluid component in the first disk-shaped container.

10. A method as in claim 9 including separating the containers from one another and sealing each container.

11. A method as in claim 8 wherein the centrifuge is a dual member centrifuge.

12. A method as in claim 11 including forming a radially extending barrier member in at least said first disk-shaped container.

13. A method as in claim 11 including forming a radially extending barrier member in each of said disk-shaped containers.

14. A fluid collection set, usable in the collection of a quantity of fluid, and positionable in part in a receiving chamber of a centrifuge for the purpose of separating, by centrifugation, a selected fluid component, the set comprising:
a flexible, disk-shaped collection container defining an interior collection volume in which a quantity of fluid can be collected with said collection container having a selectively curved, sealed periphery;
a fluid flow conduit with a proximal end and a distal end, said proximal end in fluid flow communication with said interior collection volume;
a separated component container in fluid flow communication with said distal end of said conduit with said disk-shaped collection container rotatable in the receiving chamber while simultaneously coupled to said component container so as to accumulate the component separated from the quantity of fluid rotated in the receiving chamber with said proximal end of said fluid flow conduit extending into said interior collection volume a predetermined amount thereby forming an elongated, radially extending barrier.

15. A fluid collection set, usable in the collection of a quantity of fluid, and positionable in part in a receiving chamber of a centrifuge for the purpose of separating, by centrifugation, a selected fluid component, the set comprising:
a flexible, disk-shaped collection container defining an interior collection volume in which a quantity of fluid can be collected with said collection container having a selectively curved, sealed periphery said collection container formed of first and second planar plastic members sealingly joined along said curved periphery;
a fluid flow conduit with a proximal end and a distal end, said proximal end in fluid flow communication with said interior collection volume;
a separated component container in fluid flow communication with said distal end of said conduit with said disk-shaped collection container rotatable in the receiving chamber while simultaneously coupled to said component container so as to accumulate the component separated from the quantity of fluid rotated in the receiving chamber with said proximal end of said fluid flow conduit extending into said collection container through a selected region of said circular periphery.

16. A fluid collection set, usable in the collection of a quantity of whole blood, and positionable in part in a receiving chamber of a centrifuge for the purpose of separating, by centrifugation, a selected blood component, the set comprising:
a flexible, plastic, disk-shaped collection container defining an interior collection volume in which a quantity of whole blood from a donor can be collected with said collection container having a curved periphery;

a fluid flow conduit with a proximal end and a distal end, said proximal end in fluid flow communication with said interior collection volume;
a separated component container in fluid flow communication with said distal end of said conduit with said disk-shaped collection container rotatable in the receiving chamber while simultaneously coupled to said component container so as to accumulate the component separated from the quantity of blood rotated in the receiving chamber with said proximal end of said fluid flow conduit extending into said collection volume a predetermined amount and attached to a region of the collection container thereby forming a radially extending harrier member positioned within said interior collection volume.

17. A system for separation of a component from a fluid comprising:
means for centrifugation including a rotatable receiving chamber;
a fluid collection set, usable in the collection of quantity of fluid, and positionable at least in part in said receiving chamber for the purpose of separating, by centrifugation, the selected fluid component, said set including, a flexible, disk-shaped collection container defining an interior collection volume in which the quantity of fluid can be collected with said collection container having a circular periphery, said collection container with the quantity of fluid positionable in said receiving chamber;
a fluid flow conduit with a proximal end and a distal end, said proximal end in fluid flow communication with said interior collection volume;
a separated component container in fluid flow communication with said distal end of said conduit with said disk-shaped collection container rotatable in the receiving chamber while simultaneously coupled to said component container so as to accumulate the component separated from the quantity of fluid rotated in said receiving chamber with said collection container formed of first and second planar plastic members sealingly joined along said circular periphery, a barrier member positioned within said collection container between said sealed planar plastic members, with said proximal end of said fluid flow conduit extending into said collection volume a predetermined amount thereby forming said barrier member.

18. A set as in claim 17 with said barrier formed as an elongated, generally radially extending member.

19. A system as in claim 17 with said distal end essentially non-rotatable with respect to said proximal end.

20. A system as in claim 19 with said separated component container positionable within said receiving chamber.

21. A system as in claim 19 with said separated component container fixedly positionable outside of said centrifugation means.

22. A fluid collection set, usable in the collection of a quantity of fluid, and positionable in part in a receiving chamber of a centrifuge for the purpose of separating, by centrifugation, a selected fluid component, the set comprising:
a flexible, disk-shaped collection container defining an interior collection volume in which a quantity of fluid can be collected with said collection container having a circular, sealed periphery, and a generally radial container wall heat seal line extending from said periphery toward a center thereof, thereby blocking circumferential fluid flow along said periphery;
a fluid flow contact with a proximal end and a distal end, said proximal end in fluid flow communication with said interior collection volume;

a separated component containiner in fluid flow communication with said distal end of said conduit with said disk-shaped collection container rotatable in the receiving chamber while simultaneously coupled to said component container so as to accumulate the component separated from the quantity of fluid rotated in the receiving chamber.

23. A set as in claim 22 with said collection container formed of first and second planar plastic members sealingly joined along said circular periphery.

24. A set as in claim 23 with said conduit formed as a flexible tubular member.

25. A set as in claim 23 including a second separated component container in fluid flow communication with said collection container.

26. A set as in claim 25 including means for filling said collection container.

27. A set as in claim 22 wherein the centrifuge is a dual member centrifuge.

28. A set as in claim 27 with said separated component container positionable, fixedly located outside of the centrifuge.

29. A set as in claim 28 with said generally radially extending heat seal line formed as a radially extending sealed region between first and second planar plastic members.

30. A set as in claim 22 wherein said proximal end of said fluid flow conduit is located in a region of said collection volume which will contain only the separated fluid component after centrifugation has taken place.

31. A fluid collection set, usable in the collection of a quantity of whole blood, and positionable in part in a receiving chamber of a centrifuge for the purpose of separating, by centrifugation, a selected blood component, the set comprising:
a flexible, plastic, disk-shaped collection container defining an interior collection volume in which a quantity of whole blood from a donor can be collected with said collection container having a circular periphery with first and second opposed walls of said container sealed together with a generally radial heat seal line extending from a region of said circular periphery toward a center thereof to form a barrier to circumferential flow adjacent said periphery;
a fluid flow circuit with a proximal end and a distal end, said proximal end in fluid flow communication with said interior collection volume;
a separated component container in fluid flow communication with said distal end of said conduit with said disk-shaped collection container rotatable in the receiving chamber while simultaneously coupled to said component container so as to accumulate the component separated from the quantity of blood rotated in the receiving chamber.

32. A set as in claim 31 with said collection chamber formed of first and second planar plastic members sealingly joined along said circular periphery.

33. A set as in claim 32 with said proximal end of said fluid flow conduit extending into said collection chamber through a selected region of said curved periphery.

34. A set as in claim 33 with said proximal end extending into a region of said collection container containing essentially only the separated component after centrifugation has taken place.

35. A set as in claim 32 including a second separated component container in fluid flow communication with said collection container.

36. A set as in claim 35 including means for filling said disk-shaped collection container with the quantity of whole blood.

37. A set as in claim 35 wherein the centrifuge is a dual member centrifuge and with said proximal end of said fluid flow conduit essentially non-rotatable with respect to said distal end.