TECHNICAL FIELD OF THE INVENTION This invention relates generally to the field of systems for driving fluids through an extracorporeal blood circuit, and specifically to non-disposable systems for driving and controlling fluid flow through disposable extracorporeal blood circuit kits.
BACKGROUND OF THE INVENTION Several treatments for disease require the removal of blood from a patient, processing the one or more components of the blood, and return of the processed components for a therapeutic effect. Those extracorporeal treatments require systems for safely removing blood from the patient, separating it into components, and returning the blood or blood components to the patient. With the advance of medical sciences, it has become possible to treat a patient's blood in closed-loop processes, returning the patient's own treated blood back to him in one medical treatment. An example of such processes include external treatment methods for diseases in which there is a pathological increase of lymphocytes, such as cutaneous T-cell lymphoma or other diseases affecting white blood cells. In such methods, the patient's blood is irradiated with ultraviolet light in the presence of a chemical or an antibody. Ultraviolet light affects the bonding between the lymphocytes and the chemical or antibody that inhibits the metabolic processes of the lymphocytes.
Photopheresis systems and methods have been proposed and used which involve separation of buffy coat from the blood, addition of a photoactivatable drug, and UV irradiation of the buffy coat before re-infusion to the patient. Extracorporeal photopheresis may be utilized to treat numerous diseases including Graft-versus-Host disease, Rheumatoid Arthritis, Progressive Systematic Sclerosis, Juvenile Onset Diabetes, Inflammatory Bowel Disease and other diseases that are thought to be T-cell or white blood cell mediated, including cancer. Apheresis systems and methods have also been proposed and used which involve separation of blood into various components.
Additionally, apheresis systems and methods have also been proposed and used which involve separation of blood into various components, and also involve systems pumping and valving systems which are difficult to manufacture or operate. Prior photopheresis and apheresis systems and methods usually require batch processes and therefore take several hours to treat a patient or to obtain a sufficient supply of separated blood components. Furthermore, the systems are very complex to manufacture, especially the fluid flow controllers and valving systems.
In known photopheresis systems, a disposable kit is provided that is loaded into a permanent piece of hardware. The disposable kit contain complex tubing that is used to carry blood fluids to and from the various devices included in the kit, such as a centrifuge bowl, an irradiation chamber, and various bags for delivering and/or collecting blood fluids. Known disposable kits often contain a cassette, or other controller mechanism, for controlling the flow of blood fluids throughout the disposable kit and to and from the patient. Disposable kits are used only once and must be replaced or disposed after each treatment session. In performing a treatment process, the kit is connected to patient to form a closed-loop system and the various devices of the disposable kit are loaded into a permanent piece of equipment used to drive blood fluids throughout the disposable kit as necessary. Once loaded, the permanent blood drive system drives the blood fluids through the kit's fluid circuitry.
Known permanent blood driving systems have control decks for receiving the cassette of the disposable cassette. In preparing for a blood treatment process, an operator must properly load the cassette into the deck and load the other devices of the kit into their appropriate positions. It is vital that the cassette be loaded properly and not be able to move during treatment. It is also vital to ensure that the disposable kit being loaded onto the permanent blood driving system is compatible with the blood driving system and capable of carrying out the intended treatment. However, these goals must be balanced with the competing goals of reducing the complexity of cassette clamping mechanisms so as to reduce operator loading errors and reducing kit loading time.
Another very real advancement in photopheresis systems would result if the size, manufacturing complexity, manufacturing costs, and tubing within the disposable kit could be reduced, even at the cost of a more complex blood driving system. This is because the blood driving system represents permanent reusable equipment, whereas a new sterile disposable kit must be used each time. Known disposable photopheresis kits are difficult and expensive to manufacture, especially the valving and pumping mechanisms within the cassette.
The size of existing permanent blood driving systems is another issue. Known blood driving systems are bulky and have a very large footprint, taking up valuable hospital floor space. Thus, the above goals must be achieved while maintaining, preferably reducing, the footprint of the permanent blood driving system.
Another deficiency in existing blood driving systems is their inability to communicate or receive real time data during a treatment. If a problem arises during the treatment, either the problem will not be detected and/or nothing can be done until after the treatment. Thus, a need exists for a blood driving system that can both communicate real time data during a treatment and respond if necessary to data inputs in real time during a treatment process.
Additionally, prior photopheresis and apheresis systems and methods usually require batch processes and therefore take several hours to treat a patient or to obtain a sufficient supply of separated blood fragments. It is a constant object to reduce the time it takes to perform a complete photopheresis or apheresis treatment session. Another object is to reduce the amount of blood that must be drawn form a patient and processed in closed-loop processes per photopheresis treatment session. Yet another object to increase the amount of white blood cell yield or obtain a cleaner cut of buffy coat per volume of whole blood processed. Still another object is to reduce the costs and complexity associated with making the disposable kits used.
DISCLOSURE OF THE INVENTION These objects and others are met by the present invention. The present invention is directed at permanent blood driving systems for photopheresis and apheresis to provide less complex, easier to manufacture, and a continuous process for separation of sufficient fragment for treatment so as to greatly reduce the treatment time.
The invention, in one aspect, is an improved deck for driving fluids through an extracorporeal blood circuit kit. The kit including a cassette for controlling fluid flow and having at least one tab protruding from a housing of the cassette. The deck is designed to allow easy, quick, and reliable loading of the cassette through the use a new cassette clamping mechanism. In this aspect, the deck comprises: a controller; a plate having a cassette loading area; at least one catch for slidably receiving a corresponding tab of the cassette, the catch positioned on the plate adjacent to the cassette loading area; at least one rotating clamp rotatable between an open position and a closed position, the rotating clamp positioned on the plate adjacent to the cassette loading area; wherein when the rotating clamp is in the open position, the rotating clamp does not obstruct the cassette from being removed from the cassette loading area; and wherein when the rotating clamp is in the closed position and the cassette loaded onto the cassette loading area, the rotating clamp prohibits the cassette from being removed from the cassette loading area.
It is preferable that the rotating clamps rotate about an axis that is substantially perpendicular to a top surface of the plate. It is further preferable that the rotating clamps be spring loaded so as to return to the closed position when rotational force is not applied and that the rotational clamps be operably coupled by a timing belt so that rotation of all rotating clamps is coordinated. Providing two catches and two rotating clamps is most preferable.
Each rotating clamp will preferably have an angled ledge that allows the cassette to be lowered onto the cassette loading area of the plate while the rotating clamps are in closed position. The angled ledge will also prohibit the cassette from being raised from the cassette loading area when the rotating clamps are in the closed position. Rotation between the open and closed positions can be facilitated by pneumatic cylinders.
When the above claiming mechanism is provided on a deck, a cassette can be loaded onto the deck by aligning the tabs of the cassette with the catches, slidably inserting the tabs into the catches, and pressing the cassette downward onto the cassette loading area. As the cassette is forced downward against the rotating clamps, the rotating clamps are rotated to the open position allowing the cassette to move below the angled ledge. When the cassette is below the angled ledges, the rotating clamps snap back to the closed position locking the cassette onto the cassette loading area. When this happens the cassette can not be removed or moved until the rotating clamps are moved to the open position after treatment is complete or until the operator does so manually. This setup provides little or no chance for operator error in loading the cassette and is time efficient.
Turning now to other elements of the inventive deck, it is preferred that the deck also have at least one compression actuator adapted to move between a raised position and a lowered position. When the cassette is loaded onto the cassette loading area, and the compression actuator is in the raised position, the compression actuator will occlude a portion of flexible tubing within the cassette by compressing the portion of flexible tubing against a housing of the cassette. As such, the compression actuators act as valves to control and direct fluid flow through desired fluid passageways of the kit. There are preferably eight compression actuators.
It is further that at least one of the compression actuators be spring loaded so as to return the compression actuator to the raised position when force is not applied and that at least one compression actuator be spring retracted so as to return the compression actuator to the lowered position when force is not applied. More preferably, the deck has three compression actuators that are spring loaded and positioned on the plate so that when a cassette is loaded onto the cassette loading area, the three spring loaded compression actuators are aligned with portions of flexible tubing within the cassette that are connected directly to a patient. These three compression actuators can be coupled to one another so that their movement between the lowered and raised positions is coordinated. It is also preferred that the deck have five compression actuators that are spring retracted and positioned on the plate so that when a cassette is loaded onto the cassette loading area, the five compression actuators are aligned with portions of flexible tubing within the cassette so as to be able to route fluids throughout the kit.
For patient safety, it is most preferable that the deck have an air bubble detector adapted to monitor tubes of the kit that are carrying fluids to and from a patient when the cassette is loaded onto the cassette loading area. When the air bubble detector detects an air bubble, it will take the necessary actions to prohibit flow of fluids to and from the patient.
The deck will also preferably have at least one peristaltic pump adjacent to the cassette loading area for driving fluids through the kit. The peristaltic pump will comprise a rotor rotatably mounted about a rotor axis; a housing having a curved wall surrounding at least a portion of the rotor and forming a tube pumping region between the rotor and the curved wall; the rotor comprising at least one drive roller for progressively compressing a loop of tubing against the curved wall; the rotor comprising a flange above the housing and an angled guide extending upward from the flange for displacing the loop of tubing toward the flange upon the rotor being rotated in a forward direction; the flange having an opening with a leading edge and a trailing edge for capturing and feeding the loop of tubing into the tube pumping region upon the rotor being rotated in the forward direction; and wherein the trailing edge is higher than the leading edge. Most preferably, five peristaltic pumps are provided.
A hematocrit sensor for monitoring a tube of the kit that leads to a treatment bag for the presence of red blood cells is also preferably provided. The hematocrit sensor can be coupled to the controller to control the peristaltic pump that drives fluid into the tube that leads into the treatment bag.
In another aspect, the invention is a system for driving blood fluids through a disposable kit comprising: a housing having the deck described above; a centrifuge chamber within the housing; and an infrared communication port coupled to the controller. Preferably, the infrared communication port is adapted to transmit real time data relating to a therapy session being performed on the system to a remote device. Infrared communication abilities allow the system to be able to both transmit and receive data in real time during a treatment process without disturbing the treatment.
When the system is adapted to be used for photopheresis treatments, the system will further comprise a photoactivation chamber for receiving an irradiation chamber of the kit. The photoactivation chamber can be vertically oriented. It is more preferable that a leak detector be provided in the photoactivation chamber and that the leak detector comprises at least two U-shaped electrodes, a solid state switch connected to a first end of the electrodes, and an integrated circuit connected to a second end of the electrodes. The leak detector is coupled to the controller. It is still further preferable that a similar leak detector also be provided in the centrifuge chamber.
A means to authenticate a unique identifier associated with the kit is also preferably provided on the system. The authentication means is coupled to the controller. The means to authenticate can be a data card receiving slot.
In yet another aspect, the invention is a blood diving system having an upright tower configuration that reduces the footprint of the system, saving valuable hospital floor space. In this embodiment, the system will comprise: a controller; a base portion having a top having a deck for receiving and controlling a cassette for directing fluid flow through the kit; an upper portion atop the top; and a centrifuge chamber within the upper portion. Placing the centrifuge chamber above the deck reduces the footprint of the system and provide a working platform for the operator to place objects on.
When adapted to be used for photopheresis treatments, the system will have a photoactivation chamber in the base portion for receiving an irradiation chamber of the kit. The photoactivation chamber will be preferably vertically oriented and have a leak detector
The system is provided with wheels for mobility and is preferably designed to have a height of the system is less than about60 inches so as not to obstruct visibility during moving. Additionally, the system can be provided with all of the features discussed above.
BRIEF DESCRIPTION OF THE DRAWINGS The invention is described in detail with respect to the accompanying drawings, which illustrate an embodiment of the inventive apparatus, assemblies, systems, and methods.
FIG. 1 is a schematic representation of an embodiment of a disposable-kit for use in photopheresis therapy embodying features of the present invention.
FIG. 2 is an elevated perspective view of an embodiment of a cassette for controlling fluid flow in the disposable photopheresis kit ofFIG. 1.
FIG. 3 is an exploded view of the cassette ofFIG. 2.
FIG. 4 is a top view of the cassette ofFIG. 2 with the cover removed and showing internal tubular circuitry.
FIG. 5 is a bottom view of a cover of cassette ofFIG. 2.
FIG. 6 is an elevated perspective view of an embodiment of a filter assembly.
FIG. 7 is bottom perspective view of the filter assembly ofFIG. 6.
FIG. 8 is an exploded view of the filter assembly ofFIG. 6.
FIG. 9 is a rear perspective view of the filter assembly ofFIG. 6.
FIG. 10 is schematic representation of the filter assembly ofFIG. 6 coupled to pressure sensors and a data processor.
FIG. 11 is a front view of an irradiation chamber.
FIG. 12 is a side longitudinal view of the irradiation chamber ofFIG. 11.
FIG. 13 is a side transverse view of the irradiation chamber ofFIG. 11
FIG. 14 is a cut-away view of a section of the first plate and the second plate prior to being joined together to form the irradiation chamber ofFIG. 11.
FIG. 15 is a cut-away dimensional end view of the irradiation chamber ofFIG. 11.
FIG. 16 is a perspective view of the irradiation chamber ofFIG. 11 positioned within a UVA light assembly.
FIG. 17 is an elevated perspective view of an embodiment of a permanent tower system for use in conjunction with a disposable kit for facilitating a photopheresis therapy session.
FIG. 18 is a cross-sectional view of an embodiment of the photoactivation chamber, without a UVA light assembly, used in the tower system ofFIG. 17.
FIG. 19 is a cross-sectional view of an embodiment of the centrifuge chamber used in the tower system ofFIG. 17.
FIG. 20 is an electrical schematic of the leak detection circuit provided in the photoactivation chamber ofFIG. 18.
FIG. 21 is an electrical schematic of the leak detection circuit provided in the centrifuge chamber ofFIG. 19.
FIG. 22 is an elevated perspective view of an embodiment of the fluid flow control deck of the tower system ofFIG. 17.
FIG. 23 is a perspective bottom view of the control deck ofFIG. 22.
FIG. 24 is an exploded view of the control deck ofFIG. 22.
FIG. 25 is a top perspective view of the control deck ofFIG. 22 with the cassette ofFIG. 2 loaded thereon.
FIG. 26 is a flowchart of an embodiment of a photopheresis treatment process.
FIG. 27 is a schematic of an embodiment of the fluid flow circuit used in performing the treatment process ofFIG. 26.
FIG. 28 is top perspective view an embodiment of a peristaltic pump.
FIG. 29 is a cross sectional side view of the peristaltic pump ofFIG. 28.
FIG. 30 is a top perspective view the rotor of the peristaltic pump ofFIG. 29.
FIG. 31 is a bottom perspective view of the rotor ofFIG. 30.
FIG. 32 is a top view of the peristaltic pump ofFIG. 28.
FIG. 33 is a top view of the peristaltic pump ofFIG. 28 in a loading position and near the cassette ofFIG. 2.
FIG. 34 is an electrical schematic of the infrared communication port circuit.
FIG. 35 illustrates an embodiment of a centrifuge bowl and a rotating frame.
FIG. 36 is a dimensional view of the bowl ofFIG. 35.
FIG. 37 is an exploded view of the bowl ofFIG. 36.
FIG. 38 shows a cross sectional view of the bowl ofFIG. 36 along the line XIX-XIX.
FIG. 39A shows a cross sectional view of a connection sleeve in place with a lumen connector of the bowl ofFIG. 38 along the line XX.
FIG. 39B shows another cross sectional view of a connection sleeve in place with a lumen connector of the bowl ofFIG. 38.
FIG. 40 shows a cross sectional view of the top core of the bowl ofFIG. 37.
FIG. 41 shows a dimensional view of the top core and upper plate ofFIG. 37.
FIG. 42 shows a bottom view of the top core ofFIG. 41.
FIG. 43A shows a dimensional exploded view of the bottom core and a lower plate of the bowl ofFIG. 37.
FIG. 43B shows an dimensional cross section view of the bottom core and a lower plate of the bowl ofFIG. 43A attached together.
FIG. 44 shows an exploded side view of the bottom core and a lower plate ofFIG. 43A.
FIG. 45 shows a dimensional view of another embodiment of a conduit assembly.
FIG. 46 shows a dimensional view of the connection sleeve ofFIG. 45.
FIG. 47 shows a dimensional view of one end of conduit assembly ofFIG. 45.
FIG. 48 shows a dimensional view of an anchor end of the present invention.
FIG. 49 shows a lateral cross-sectional view of an anchor end.
FIG. 50 shows a horizontal cross-sectional view of an anchor end taken along line XXI.
FIG. 51 illustrates a dimensional view of the rotating frame ofFIG. 35.
FIG. 52 is an enlarged view of a holder for an external conduit.
FIG. 53 shows an alternative embodiment of the bowl with the cross-section taken similarly to that shown inFIG. 38.
FIG. 54 shows an alternative embodiment of the top core.
FIG. 55 shows an alternative embodiment of the connection sleeve.
MODES FOR CARRYING OUT THE INVENTION Features of the present invention are embodied in the permanent blood driving equipment, the disposable photopheresis kit, the various devices which make up the disposable kit, and the corresponding treatment process. The following written description is outlined as follows:
I. Disposable Photopheresis Kit
- A. Cassette for Controlling Fluid Flow
- B. Irradiation Chamber
- C. Centrifuge Bowl
II. Permanent Tower System
- A Photoactivation Chamber
- B. Centrifuge Chamber
- C. Fluid Flow Control Deck
- 1. Cassette Clamping Mechanism
- 2. Self-Loading Peristaltic Pumps
- D. Infra-Red Communication
III. Photopheresis Treatment Process
The above-outline is included to facilitate understanding of the features of the present invention. The outline is not limiting of the present invention and is not intended to categorize or limit any aspect of the invention. The inventions are described and illustrated in sufficient detail that those skilled in this art can readily make and use them. However, various alternatives, modifications, and improvements should become readily apparent without departing from the spirit and scope of the invention. Specifically, while the invention is described in the context of a disposable kit and permanent blood drive system for use in photopheresis therapy, certain aspects of the invention are not so limited and are applicable to kits and systems used for rendering other therapies, such as apheresis or any other extracorporeal blood treatment therapy.
I. Disposable Photopheresis Kit
FIG. 1 illustratesdisposable photopheresis kit1000 embodying features of the present invention. It is necessary that a new disposable sterile kit be used for each therapy session. In order to facilitate the circulation of fluids throughphotopheresis kit1000, and to treat blood fluids circulating therethrough,photopheresis kit1000 is installed in permanent tower system2000 (FIG. 17). The installation ofphotopheresis kit1000 intotower system2000 is described in detail below.
Photopheresiskit1000 comprisescassette1100,centrifuge bowl10,irradiation chamber700,hematocrit sensor1125,removable data card1195,treatment bag50, andplasma collection bag51. Photopheresiskit1000 further comprisessaline connector spike1190 andanticoagulant connector spike1191 for respectively connecting saline and anticoagulant fluid bags (not shown). Photopheresiskit1000 has all the necessary tubing and connectors to fluidly connect all devices and to route the circulation of fluids during a photopheresis treatment session. All tubing is sterile medical grade flexible tubing.Triport connectors1192 are provided at various positions for the introduction of fluids into the tubing if necessary.
Needle adapters1193 and1194 are provided for respectively connectingphotopheresis kit1000 to needles for drawing whole blood from a patient and returning blood fluids to the patient. Alternatively,photopheresis kit1000 can be adapted to use a single needle to both draw whole blood from the patient and return blood fluids to the patient. However, a two needle kit is preferred because of the ability to simultaneously draw whole blood and return blood fluids to the patient. When a patient is hooked up tophotopheresis kit1000, a closed loop system is formed.
Cassette1100 acts both as a tube organizer and a fluid flow router.Irradiation chamber700 is used to expose blood fluids to UV light.Centrifuge bowl10 separates whole blood into its different components according to density.Treatment bag50 is a 1000 mL three port bag.Straight bond port52 is used to inject a photoactivatable or photosensitive compound intotreatment bag50.Plasma collection bag51 is 1000 mL two port bag. Bothtreatment bag50 andplasma collection bag51 have a hingedcap spike tube53 which can be used for drainage if necessary. Photopheresiskit1000 further compriseshydrophobic filters1555 and1556 which are adapted to connect topressure transducers1550 and1551 to filter1500 viavent tubes1552 and1553 for monitoring and controlling the pressures within tubes connecting the patient (FIG. 10). Monitoring the pressure helps ensure that the kit is operating within safe pressure limits. The individual devices ofphotopheresis kit1000, and their functioning, are discussed below in detail.
A. Cassette for Controlling Fluid Flow
FIG. 2 shows a top perspective view of adisposable cassette1100 for valving, pumping, and controlling the movement of blood fluids during a photopheresis treatment session.Cassette1100 hashousing1101 that forms an internal space that acts as a casing for its various internal components and tubular circuitry.Housing1101 is preferably made of hard plastic, but can be made of any suitably rigid material.Housing1101 hasside wall1104 andtop surface1105.Side wall1104 ofhousing1101 hastabs1102 and1103 extending therefrom. During a photopheresis treatment,cassette1100 needs to be secured todeck1200 oftower system2000, as is best illustrated inFIG. 25.Tabs1102 and1103 help position andsecure cassette1100 todeck1200.
Cassette1100 hasfluid inlet tubes1106,1107,1108,1109,1110,1111, and1112 for receiving fluids intocassette1100,fluid outlet tubes1114,1115,1116,1117,1118, and1119 for expelling fluids fromcassette1100, and fluid inlet/outlet tube1113 that can be used for both introducing and expelling fluids into and out ofcassette1100. These fluid input and output tubesfluidly couple cassette1100 to a patient being treated, as well as the various devices ofphotopheresis kit1000, such ascentrifuge bowl10, irradiation chamber700,treatment bag50,plasma collection bag51, and bags containing saline, anticoagulation fluid to form a closed-loop extracorporeal fluid circuit (FIG. 27).
Pump tube loops1120,1121,1122,1123, and1124 protrude fromside wall1104 ofhousing1101.Pump tube loops1120,1121,1122,1123, and1124 are provided for facilitating the circulation of fluids throughoutphotopheresis kit1000 during therapy. More specifically, whencassette1100 is secured todeck1200 for operation, each one of saidpump tube loops1120,1121,1122,1123, and1124 are loaded into a correspondingperistaltic pump1301,1302,1303,1304, and1305 (FIG. 4).Peristaltic pumps1301,1302,1303,1304, and1305 drive fluid through the respectivepump tube loops1120,1121,1122,1123, and1124 in a predetermined direction, thereby driving fluid through photopheresis kit1000 (FIG. 1) as necessary. The operation and automatic loading and unloading ofperistaltic pumps1301,1302,1303,1304, and1305 is discussed in detail below with respect toFIGS. 28-33.
Turning now toFIG. 3,cassette1100 is shown withhousing1101 in an exploded state. For ease of illustration and description, the internal tubular circuitry withinhousing1101 is not illustrated inFIG. 3. The internal tubular circuitry is illustrated inFIG. 4 and will be discussed in relation thereto.Cassette1100 hasfilter assembly1500 positioned therein and in fluid connection withinlet tube1106,outlet tube1114, and one end of each ofpump tube loops1120 and1121.Filter assembly1500 comprisesvent chambers1540 and1542.Filter assembly1500, and its functioning, is discussed in detail below with respect toFIGS. 6-10.
Housing1101 comprisescover1130 andbase1131.Cover1130 hastop surface1105, a bottom surface1160 (FIG. 5), andside wall1104.Cover1130 hasopenings1132 and1133 for allowingvent chambers1540 and1542 offilter assembly1500 to extend therethrough.Side wall1104 has a plurality oftube slots1134 to allow the inlet tubes, outlet tubes, and pump loop tubes to pass into the internal space ofhousing1101 for connection with the internal tubular circuitry located therein. Only afew tube slots1134 are labeled inFIG. 3 to avoid numerical crowding.Tabs1102 and1103 are positioned onside wall1104 so as not to interfere withtube slots1134.Cover1130 has occlusion bars1162 and1162A extending from bottom surface1160 (FIG. 5). Occlusion bars1162 and1162A are preferably molded intobottom surface1160 ofcover1130 during its formation.
Base1131 has a plurality of U-shaped tube-holders1135 extending upward fromtop surface1136.U-shaped tube holders1135 hold the inlet tubes, outlet tubes, pump loop tubes, filter assembly, and internal tubular circuitry in place. Only a fewU-shaped holders1135 are labeled inFIG. 3 to avoid numerical crowding. Preferably, aU-shaped holder1135 is provided onbase1131 at each location where an inlet tube, an outlet tube, or a pump loop tube passes through atube slot1134 onside wall1104.Male extrusions1136 protrude fromtop surface1136 ofbase1131 for mating with correspondingfemale holes1161 located onbottom surface1160 of cover1130 (FIG. 5). Preferably, amale protrusion1136 is located at or near each of the four corners ofbase1130 and nearfilter1500.Male protrusions1136 mate with thefemale holes1161 to form a snap-fit andsecure base1131 to cover1130.
Base1131 further comprises ahub1140.Hub1140 is a five-way tube connector used to connect five tubes of the internal tubular circuitry. Preferably, threeapertures1137 are located near and surround three of the tubes leading intohub1140.Hub1140 acts as a centralized junction which can be used, in conjunction with compression actuators1240-1247 (FIG. 22), to direct fluids throughphotopheresis kit1000 and to and from the patient. In addition tohub1140, appropriate tube connectors, such as T-connectors1141 and Y-connector1142, are used to obtain the desired flexible tubing pathways.
Fiveapertures1137 are located on the floor ofbase1130. Eachaperture1137 is surrounded by anaperture wall1138 havingslots1139 for passing portions of the internal tubular circuitry therethrough. Anelongated aperture1157 is also provided on the floor ofbase1131.Apertures1137 are located onbase1131 to align with corresponding compression actuators1243-1247 of deck1200 (FIG. 22).Aperture1157 is located onbase1131 to align with compression actuators1240-1242 of deck1200 (FIG. 22). Eachaperture1137 is sized so that a single compression actuator1243-1247 can extend therethrough.Aperture1157 is sized so that three compression actuators1240-1242 can extend therethrough. Compression actuators1240-1247 are used to close/occlude and open certain fluid passageways of the internal tubular circuitry in order to facilitate or prohibit fluid flow along a desired path. When it is desired to have a certain passageway open so that fluid can flow therethrough, the compression actuator1240-1247 for that passageway is in a lowered position However; when it is desired to have a certain fluid passageway closed so that fluid can not flow therethrough, the appropriate compression actuator1240-1247 is raised, extending the compression actuator1240-1247 throughaperture1137 or1157 and compressing a portion of the flexible tubular circuitry against bottom surface1160 (FIG. 5) ofcover1130, thereby closing that passageway. Preferably,occlusion bars1163 and1173 (FIG. 5) are positioned onbottom surface1160 to align with the compression actuators1240-1247 so that the portion of flexible tubing being occluded is compressed againstocclusion bar1163 or1173. Alternatively, the occlusion bar can be omitted or located on the compression actuators themselves.
It is preferable forcassette1100 to have a unique identifier that can communicate with and relay information topermanent tower system2000. The unique identifier is provided to ensure that the disposable photopheresis kit is compatible with the blood drive equipment into which it is being loaded, and that the photopheresis kit is capable of running the desired treatment process. The unique identifier can also be used as a means to ensure that the disposable photopheresis kit is of a certain brand name or make. In the illustrated example, the unique identifier is embodied as data card1195 (FIG. 2) that is inserted into datacard receiving port2001 of permanent tower system2000 (FIG. 17).Data card1195 has both read and write capabilities and can store data relating to the treatment therapy performed for future analysis. The unique identifier can also take on a variety of forms, including, for example, a microchip that interacts with the blood drive equipment when the kit is loaded, a bar code, or a serial number.
Cover1130 hasdata card holder1134 for holding data card1195 (FIG. 1).Data card holder1134 comprises four elevated ridges in a segmented rectangular shape for receiving and holdingdata card1195 tocassette1100.Data card holder1134 holdsdata card1195 in place via a snap-fit (FIG. 2).
Referring now toFIGS. 1 and 4, the internal tubular circuitry ofcassette1100 will now be discussed. At least a portion of the internal tubular circuitry is preferably made of flexible plastic tubing that can be pinched shut by the exertion of pressure without compromising the hermetic integrity of the tube.Base1131 ofcassette1100 is illustrated inFIG. 4 so that the internal tubular circuitry can be viewed.Inlet tubes1107 and1108 andoutlet tube1115 are provided forcoupling cassette1100 to centrifuge bowl10 (FIG. 1). More specifically,outlet tube1115 is provide for delivering whole blood fromcassette1100 tocentrifuge bowl10, andinlet tubes1107 and1108 are respectively provide for returning a lower density blood components and higher density blood components tocassette1100 for further routing throughphotopheresis kit1000. The lower density blood components can include, for example, plasma, leukocytes, platelets, buffy coat, or any combination thereof. The higher density components can include, for example, red blood cells.Outlet tube1117 andinlet tube1112fluidly couple cassette1100 toirradiation chamber700. More specifically,outlet tube1117 is provided for delivering an untreated lower density blood component, for example buffy coat, to irradiation chamber700 for exposure to photo energy, whileinlet tube1112 is provided for returning the treated lower density blood component tocassette1100 for further routing.
Inlet tube1111 andoutlet tube1116couple treatment bag50 tocassette1100.Outlet tube1116 is provided to deliver an untreated low density blood component, for example buffy coat, totreatment bag50.Outlet tube1116 has hematocrit (“HCT”)sensor1125 operably connected thereto to monitor for the introduction of a high density blood component, such as red blood cells.HCT sensor1125 is a photo sensor assembly and is operably coupled to a controller.HCT sensor1125 sends a detection signal to the controller when red blood cells are detected inoutlet tube1116 and the controller will take the appropriate action.Inlet tube1111 is provided to return the untreated low density blood component fromtreatment bag50 tocassette1100 for further routing.Inlet tubes1109 and1110 are respectively connected to a saline and anticoagulant storage bags (not shown) viaspikes1190 and1191 and are provided for delivering saline and an anticoagulant fluid tocassette1100 for further routing to the patient.
Inlet/Outlet tube1113 andoutlet tube1118 coupleplasma collection bag50 tocassette1100. More specifically,outlet tube1118 delivers a blood component, such as plasma, toplasma collection bag51. Inlet/Outlet tube1113 can be used to either deliver red blood cells toplasma collection bag51 fromcassette1100 or return the blood component(s) that build up inplasma collection bag51 tocassette1100 for further routing.Inlet tube1106 andoutlet tubes1119 and1114 are coupled to a patient. Specifically,outlet tube1114 is provided to return treated blood, saline, untreated blood components, treated blood components, and other fluids back to the patient.Inlet tube1106 is provided for delivering untreated whole blood (and a predetermined amount of an anticoagulant fluid) from the patient tocassette1100 for routing and treatment withinphotopheresis kit1000.Outlet tube1119 is specifically provided for delivering an anticoagulant fluid toinlet tube1106. It is preferable that all tubing is disposable medical grade sterile tubing. Flexible plastic tubing is the most preferred.
Cassette1100 has fivepump tube loops1120,1121,1122,1123, and1124 for driving blood fluids throughoutcassette1100 andphotopheresis kit1000. More specifically,pump tube loop1121 loads intowhole blood pump1301 and respectively drives whole blood in and out ofcassette1100 viainlet tube1106 andoutlet tube1115, passing throughfilter1500 along the way.Pump loop tube1120 loads intoreturn pump1302 and drives blood fluids throughfilter1500 and back to the patient viaoutlet tube1114.Pump loop tube1122 loads into redblood cell pump1305 and draws red blood cells fromcentrifuge bowl10 and drives them intocassette1100 viainlet line1108.Pump loop tube1123 loads intoanticoagulant pump1304 and drives an anticoagulant fluid intocassette1100 viainlet tube1124 and out ofcassette1100 to viaoutlet tube1119, which connects withinlet tube1106.Pump loop tube1124 loads intorecirculation pump1303 and drives blood fluids, such as plasma, throughtreatment bag50 and irradiation chamber700 fromcassette1100.
Each of peristaltic pumps1301-1305 are activated when necessary to perform the photopheresis treatment therapy according to an embodiment of the method of the present invention which is described below in relation toFIGS. 26-27. Peristaltic pumps1301-1305 can be operated one at a time or in any combination. The pumps1301-1305 work in conjunction with compression actuators1240-1247 to direct fluids through desired pathways ofphotopheresis kit1000.Apertures1137 and1157 are strategically located onbase1131 along the internal tubular circuitry to facilitate proper routing. Through the use of compression actuators1240-1247, the fluids can be directed along any pathway or combination thereof.
1. The Filter Assembly
Filter1500, which is located withincassette1100 as described above, is illustrated in detail inFIGS. 6-10. Referring first toFIGS. 6 and 7,filter1500 is illustrated fully assembled.Filter1500 comprises afilter housing1501.Filter housing1501 is preferably constructed of a transparent or translucent medical grade plastic. However, the invention is not so limited and filterhousing1501 can be constructed of any material that will not contaminate blood or other fluids that are flowing therethrough.
Filter housing1501 has four fluid connection ports extruding therefrom, namely wholeblood inlet port1502, wholeblood outlet port1503, treatedfluid inlet port1504, and treatedfluid outlet port1505. Ports1502-1505 are standard medical tubing connection ports that allow medical tubing to be fluidly connected thereto. Ports1502-1505 respectively containopenings1506,1507,1508 and1509.Openings1506,1507,1508 and1509 extend throughports1502,1503,1504 and1505, forming fluid passageways intofilter housing1501 at the desired locations.
Ports1502,1503,1504 and1505 are also used to securefilter1500 withincassette1100. In doing so,ports1502,1503,1504 and1505 can engageU-shaped fasteners1135 of cassette1100 (FIG. 3).Filter housing1501 also has aprotrusion1510 extending the bottom surface ofhousing floor1518.Protrusion1510 fits into a guide hole ofbase1131 of cassette1100 (FIG. 3).
Referring now toFIG. 8,filter1500 is illustrated in an exploded state.Filter housing1501 is a two-pieceassembly comprising roof1511 andbase1512.Roof1511 is connected to base1512 by any means known in the art, such as ultrasonic welding, heat welding, applying an adhesive, or by designingroof1511 and base1512 so that a tight fit results between the two. Whilefilter housing1501 is illustrated as a two-piece assembly, filterhousing1501 can be either a single piece structure or a multi-piece assembly.
Base1512 haschamber separation wall1513 extending upward from a top surface of housing floor1518 (FIG. 7). When base1512 androof1511 are assembled,top surface1515 ofchamber separation wall1513 contacts the bottom surface ofroof1511, forming two chambers within the filter housing,whole blood chamber1516 andfilter chamber1517. Fluid can not directly pass betweenwhole blood chamber1516 andfilter chamber1517.
Whole blood chamber1516 is a substantially L-shapedchamber having floor1514.Whole blood chamber1516 has a wholeblood inlet hole1519 and a whole blood outlet hole (not illustrated) infloor1514. Wholeblood inlet hole1519 and the whole blood outlet hole are located at or near the ends of the substantially L-shapedwhole blood chamber1516. Wholeblood inlet hole1519 forms a passageway with opening1506 ofinlet port1502 so that a fluid can flow intowhole blood chamber1516. Similarly, the whole blood outlet hole (not illustrated) forms a passageway with opening1507 ofoutlet port1503 so that fluid can flow out ofwhole blood chamber1516.
Filter chamber1517 hasfloor1520.Floor1520 has elevatedridge1521 extending upward therefrom.Elevated ridge1521 is rectangular and forms a perimeter. Whileelevated ridge1521 is rectangular in the illustrated embodiment,elevated ridge1521 can be any shape so long as it forms an enclosed perimeter. The height ofelevated ridge1521 is less than the height ofchamber separation wall1513. As such, whenroof1511 andbase1512 are assembled, space exists between the top ofelevated ridge1521 and the bottom surface ofroof1511.Elevated ridge1521 andchamber separation wall1513 form atrench1524 there between.
In order to facilitate fluid flow throughfilter chamber1517,floor1520 offilter chamber1517 has treatedfluid inlet hole1522 and treatedfluid outlet hole1523. Treatedfluid inlet hole1522 is located exterior of the perimeter formed byelevated ridge1521 and forms a passageway with opening1508 ofinlet port1504 so that a fluid can flow intofilter chamber1517 fromoutside filter housing1501. Treatedfluid outlet hole1523 is located interior of the perimeter formed byelevated ridge1521 and forms a passageway with opening1509 ofoutlet port1505 so that a fluid can flow out offilter chamber1517.
Filter1500 further comprisesfilter element1530.Filter element1530 comprisesframe1531 havingfilter media1532 positioned therein.Frame1531 has aneck1534 that forms afilter inlet hole1533.Filter element1530 is positioned infilter chamber1517 so thatframe1531 fits intotrench1524 andneck1534 surrounds treatedblood inlet hole1522.Filter inlet hole1533 is aligned with treatedfluid inlet hole1522 so that incoming fluid can freely flow throughholes1522 and1533 intofilter chamber1517.Frame1531 offilter element1530 forms a hermetic fit withelevated ridge1521. All fluid that entersfilter chamber1517 throughholes1522 and1533 must pass throughfilter media1532 in order to exitfilter chamber1517 via treatedfluid outlet hole1523.Filter media1532 preferably has a pore size of approximately200 microns.Filter media1532 can be formed of woven mesh, such as woven polyester.
Filter chamber1517 further comprisesfilter vent chamber1540 withinroof1511.Filter vent chamber1540 hasgas vent1541 in the form of a hole (FIG. 9). Becausegas vent1541 opens intofilter vent chamber1540 which in turn opens intofilter chamber1517, gases that build-up withinfilter chamber1517 can escape throughgas vent1541. Similarly,whole blood chamber1516 comprisesblood vent chamber1542 withinroof1511.Blood vent chamber1541 hasgas vent1543 in the form of a hole. Becausegas vent1543 opens intoblood vent chamber1542 which in turn opens intowhole blood chamber1517, gases that build-up inwhole blood chamber1516 can escape viagas vent1543.
FIG. 10 is a top view offilter1500 havingpressure sensors1550 and1551 connected togas vents1541 and1543.Pressure sensors1550 and1551 are preferably pressure transducers.Pressure sensor1550 is connected togas vent1541 viavent tubing1552.Vent tubing1552 fits intogas vent1541 so as to form a tight fit and seal. Becausegas vent1541 opens intofilter vent chamber1540 which in turn opens intofilter chamber1517, the pressure invent tubing1552 is the same as infilter chamber1517. By measuring the pressure invent tubing1552,pressure sensor1550 also measures the pressure withinfilter chamber1517. Similarly,pressure sensor1551 is connected togas vent1543 viavent tubing1553.Vent tubing1553 fits intogas vent1543 so as to form a tight fit and seal andpressure sensor1551 measures the pressure withinwhole blood chamber1516.Filter vent chamber1540 andblood vent chamber1542 extend throughopenings1132 and1133 ofcassette1100 whenfilter1500 is positioned therein (FIG. 2). This allows the pressure withinchambers1516 and1517 to be monitored while still protectingfilter chamber1500 and the fluid connections thereto.
Pressure sensors1550 and1551 are coupled tocontroller1554, which is a properly programmed processor.Controller1554 can be a main processor used to drive the entire system or can be a separate processor coupled to a main processor.Pressure sensors1550 and1551 produce electrical output signals representative of the pressure readings withinchambers1517 and1516 respectively.Controller1554 receives on a frequent or continuous basis data representing the pressure withinchambers1516 and1517.Controller1554 is programmed with values representing desired pressures withinchambers1516 and1517.Controller1554 continuously analyzes the pressure data it receives frompressure sensors1550 and1551 to determine whether the pressure readings are within a predetermined range from the desired pressure forchambers1517 and1516.Controller1554 is also coupled towhole blood pump1301 and returnpump1302. In response to the pressure data received frompressure sensors1551 and1550,controller1554 is programmed to control the speed ofwhole blood pump1301 and returnpump1302, thereby adjusting the flow rates through thepumps1301 and1301. Adjusting these flow rates in turn adjust the pressure withinwhole blood chambers1516 andfilter chamber1517 respectively. It is in this way that the pressure within the lines drawing and returning blood to and from the patient is maintained at acceptable levels.
The functioning offilter1500 during a photopheresis therapy session will now be discussed in relation toFIGS. 1, 6, and10. While the functioning offilter1500 will be described in detail with respect to drawing whole blood from a patient and returning a component of said whole blood back into the patient after it is treated, the invention is not so limited.Filter1500 can be used in connection with almost any fluid, including red blood cells, white blood cells, buffy coat, plasma, or a combination thereof.
Whole blood pump1601 draws whole blood from a patient who is connected tophotopheresis kit1000 via a needle connected toport1193. The rotational speed of whole blood pump is set so that the pressure of the line drawing the whole blood from the patient is at an acceptable level. Upon being drawn from the patient, the whole blood passes intocassette1100 viainlet tube1106.Inlet tube1106 is fluidly connected toinlet port1502 offilter1500. The whole blood passes throughopening1506 ofinlet port1502 and into L-shapedwhole blood chamber1516. The whole blood enterschamber1516 throughinlet hole1519 which is located onfloor1514. As more whole blood enterschamber1516, the whole blood spills alongfloor1514 until it reaches the whole blood outlet hole (not illustrated) at the other end of L-shapedwhole blood chamber1516. As discussed above, the whole blood outlet whole forms a passageway with opening1507 ofoutlet port1503. The whole blood that is withinchamber1516 flows acrossfloor1514, through the whole blood outlet hole, intooutlet port1503, and out offilter1500 throughopening1507.
As the whole blood passes throughwhole blood chamber1516, gases that are trapped in the whole blood escape. These gases collect inblood vent chamber1542 and then escape viagas vent1543.Pressure sensor1551 continuously monitors the pressure withinblood chamber1516 throughvent tube1553 and transmits corresponding pressure data tocontroller1554.Controller1554 analyzes the received pressure data and if necessary adjusts the speed ofwhole blood pump1301, thereby adjusting the flow rate and pressure withinchamber1516 andinlet tube1106.Controller1554 adjust the pump speed to ensure that the pressure is within the desired pressure range.
The whole blood then exitsfilter1500 throughoutlet port1503 and passes out ofcassette1100 viaoutlet tube1115. The whole blood is then separated into components and/or treated as described in detail below. Before being returned to the patient, this treated fluid (i.e. treated blood or blood components) must be filtered. Untreated fluids such as red blood cells also must be filtered and will subjected to the below filtering process. The treated fluid is fed intofilter chamber1517 through opening1508 ofinlet port1504.Inlet port1504 is fluidly connected to pumploop tube1120. The treated fluid entersfilter chamber1517 throughinlet hole1522 and passes throughfilter inlet hole1533 offilter element1530. The treated fluid fillsfilter chamber1517 until it spills overframe1531 offilter element1530, which is secured toelevated ridge1521. The treated fluid passes throughfilter media1532.Filter media1532 removes contaminants and other undesired materials from the treated fluid while at the same facilitating the release of trapped gases from the treated fluid. The treated fluid that passes throughfilter media1532 gathers onfloor1520 offilter chamber1517 within the perimeter formed byelevated ridge1521. This treated fluid then passes into treatedfluid outlet hole1523 and out offilter1500 through opening1506 ofoutlet port1502. The treated fluid is then returned to the patient viaoutlet tube1114, which is fluidly connected tooutlet port1502. The treated fluid is driven throughfilter chamber1517 andoutlet tube1114 byreturn pump1302.
Gases that are trapped in the treated fluid escape and collect infilter vent chamber1540 as the treated fluid flows throughfilter chamber1517. These gases then escapefilter1500 viagas vent1541.Pressure sensor1550 continuously monitors the pressure withinfilter chamber1517 throughvent tube1552 and transmits corresponding pressure data tocontroller1554.Controller1554 analyzes the received pressure data and compares it to the desired pressure value and range. If necessary,controller1554 adjusts the speed ofreturn pump1302, thereby adjusting the flow rate and pressure withinchamber1517 andoutlet tube1114.
B. Irradiation Chamber
FIGS. 11-16 illustrate irradiation chamber700 ofphotopheresis kit1000 in detail. Referring first toFIG. 11, irradiation chamber700 is formed by joining two plates, a front and a back plate having a thickness of preferably about 0.06 in. to about 0.2 in., which are preferably comprised of a material ideally transparent to the wavelength of electromagnetic radiation. In the case of ultraviolet A radiation, polycarbonate has been found most preferred although other materials such as acrylic may be employed. Similarly, many known methods of bonding may be employed and need not be expanded on here.
Thefirst plate702 has afirst surface712 and asecond surface714. In a preferred embodiment thefirst plate702 has afirst port705 on afirst surface712, in fluid communications with thesecond surface714. Thesecond surface714 of thefirst plate702 has a raisedboundary726A defining an enclosure. Theboundary726A preferably extends substantially perpendicular from the second surface714 (i.e. about80-100 degrees). Extending from the second surface714 (preferably substantially perpendicularly) are raisedpartitions720A. Theboundary726A surrounds thepartitions720A. One end of eachpartition720A extends and contacts theboundary726A.
Thesecond plate701 has afirst surface711 and asecond surface713. In a preferred embodiment thesecond plate701 preferably has asecond port730 on afirst surface711, in fluid communications with thesecond surface713. Thesecond surface713 of theback plate701 has a raisedboundary726B defining an enclosure. Theboundary726B preferably extends substantially perpendicular from the second surface713 (i.e. about 80-100 degrees). Extending from the second surface713 (preferably substantially perpendicular) are raised partitions (720B). Theboundary726B surrounds thepartitions720B. One end of eachpartition720A extends and contacts one side of boundary (726B).
The joining of the second surfaces of the first and second plates results in a fluid tight junction betweenboundaries726A and726B thereby formingboundary726.Partitions720A and720B are also joined forming a fluid tight junction thereby formingpartition720. Theboundary726 forms an irradiation chamber700 and together with thepartitions720 provides apathway710 havingchannels715 for conducting fluid. The pathway maybe serpentine, zig-zag, or dove-tailed. Currently preferred is a serpentine pathway.
With reference toFIG. 11 and12, irradiation chamber700 comprises aserpentine pathway710 for conducting patient fluid, such as buffy coat or white blood cells, frominlet port705 tooutlet port730, i.e., theserpentine pathway710 is in fluid communication withinlet port705 offront plate702 andoutlet port730 ofback plate701. Patient fluid is supplied fromcassette1100 toinlet port705 viaoutlet tube1117. After photoactivation and passing throughserpentine pathway710, the treated patient fluid is returned tocassette1100 via inlet tube1112 (FIGS. 1 and 4). The patient fluid is driven byrecirculation pump1303. Self-shielding effects of the cells is reduced while the cells are photoactivated by irradiation impinging upon both sides of irradiation chamber700.
FIG. 11 showspin740 andrecess735 which align the two plates of irradiation chamber prior to being joined together in a sealing arrangement by RF welding, heat impulse welding, solvent welding or adhesive bonding. Joining of the plates by adhesive bonding and RF welding is more preferred. Joining of the front and back plates by RF welding is most preferred as the design of the raisedpartitions720 and perimeter725 minimizes flashing and allows for even application of RF energy. Locations ofpin740 andrecess735 may be insideserpentine pathway710 or outside ofserpentine pathway710.FIG. 2 also shows a view of an irradiation chamber with axis L. Rotation ofchamber700180 degree about axis L gives the original configuration of the irradiation chamber. The irradiation chamber of the present invention has C2symmetry about axis L.
Referring toFIGS. 11, 13, and16, the leukocyte enriched blood, plasma, and priming solution are delivered throughinlet port705 offront plate702 of irradiation chamber700 intochannel715. Thechannel715 in the irradiation chamber700 is relatively “thin” (e.g. on the order of approximately 0.04″ as distance between two plates) in order to present large surface area of leukocyte rich blood to irradiation and reduce the self-shielding effects encountered with lower surface area/volume ratios. The cross section shape ofchannel715 is substantially rectangular (e.g. rectangular, rhomboidal or trapezoidal) which has as its long side the distance betweenpartition720 and the distance between the plates as its short side. The shape of the cross section is designed for optimal irradiation of cells passing throughchannel715. While aserpentine pathway710 is preferred in order to avoid or minimize stagnant areas of flow, other arrangements are contemplated.
Theirradiation chamber700 allows efficient activation of photoactivatable agents by irradiation from a light array assembly, such as the PHOTOSETTE®'s two banks of UVA lamps (758) for activation (FIG. 16). The irradiation plate and UVA light assembly (759) are designed to be used in a setting whereedge706 is oriented downward and edge707 points upward. In this orientation, fluids enteringinput port705 can exit fromoutlet port730 with the aid of gravity. In the most preferred embodiment, irradiation of both sides of the irradiation chamber takes place concurrently while still permitting facile removal of the chamber. UVAlight assembly759 is located withinUV chamber750 of permanent tower system2000 (FIGS. 17 and 18).
The irradiation chamber's fluid pathway loops to form two or more channels in which the leukocyte-enriched blood is circulated during photoactivation by UVA light. Preferably,irradiation chamber700 has between 4 to 12 channels. More preferably, the irradiation chamber has 6 to 8 channels. Most preferably, the irradiation chamber has 8 channels.
FIG. 14 shows cut-away views of the irradiation chamber. Thechannels715 ofserpentine pathway710 are formed by the joining of raisedpartition720 andperimeter726 of the plates.
The irradiation chamber of the present invention can be made from a biocompatible material and can be sterilized by known methods such as heating, radiation exposure or treatment with ethylene oxide (ETO).
The method of irradiating cells usingirradiation chamber700 during extracorporeal treatment of cells with electromagnetic radiation (UVA) to be used in the treatment of a patient (such as to induce apoptosis in the cells and administer the cells into the patient) will now be discussed. Preferably the cells treated will be white cells.
In one embodiment of this method, a photoactivatable or photosensitive compound is first administered to at least a portion of the blood of a recipient prior to the extracorporeal treatment of the cells. The photoactivatable or photosensitive compound may be administered in vivo (e.g., orally or intravenously). The photosensitive compound, when administered in vivo may be administered orally, but also may be administered intravenously and/or by other conventional administration routes. The oral dosage of the photosensitive compound may be in the range of about 0.3 to about 0.7 mg/kg., more specifically, about 0.6 mg/kg.
When administered orally, the photosensitive compound may be administered at least about one hour prior to the photopheresis treatment and no more than about three hours prior to the photopheresis treatment. If administered intravenously, the times would be shorter. Alternatively, the photosensitive compound may be administered prior to or contemporaneously with exposure to ultraviolet light. The photosensitive compound may be administered to whole blood or a fraction thereof provided that the target blood cells or blood components receive the photosensitive compound. A portion of the blood could first be processed using known methods to substantially remove the erythrocytes and the photoactive compound may then be administered to the resulting enriched leukocyte fraction. In one embodiment, the blood cells comprise white blood cells, specifically, T-cells.
The photoactivatable or photosensitive compound may, in the case of some psoralens, be capable of binding to nucleic acids upon activation by exposure to electromagnetic radiation of a prescribed spectrum, e.g., ultraviolet light.
Photoactive compounds may include, but are not limited to, compounds known as psoralens (or furocoumarins) as well as psoralen derivatives such as those described in, for example, U.S. Pat. No. 4,321,919 and U.S. Pat. No. 5,399,719. The photoactivatable or photosensitive compounds that may be used in accordance with the present invention include, but are not limited to, psoralen and psoralen derivatives; 8-methoxypsoralen; 4,5′8-trimethylpsoralen; 5-methoxypsoralen; 4-methylpsoralen; 4,4-dimethylpsoralen; 4-5′-dimethylpsoralen; 4′-aminomethyl-4,5′,8-trimethylpsoralen; 4′-hydroxymethyl-4,5′,8-trimethylpsoralen; 4′,8-methoxypsoralen; and a 4′-(omega-amino-2-oxa) alkyl-4,5′,8-trimethylpsoralen, including but not limited to 4′-(4-amino-2-oxa)butyl-4,5′,8-trimethylpsoralen. In one embodiment, the photosensitive compound that may be used comprises the psoralen derivative, amotosalen (S-59) (Cerus, Corp., Concord, Calif.). See, e.g., U.S. Pat. Nos. 6,552,286; 6,469,052; and 6,420,570. In another embodiment, the photosensitive compound that may be used in accordance with the invention comprises 8-methoxypsoralen.
Methoxsalen is a naturally occurring photoactive substance found in the seed of the Ammi majus (umbelliferae plant). It belongs to a class of compounds known as psoralens or furocoumarins. The chemical name is 9-methoxy-7H-furo[3,2-g][1]-benzopyran-7-one. The formulation of the drug is a sterile liquid at a concentration of 20 mcg/mL in a 10 mL vial. See http://www.therakos.com/TherakosUS/pdf/uvadexpi.pdf. Toxicology studies of extracorporeal photopheresis and different dosages of UVADEX® and ultraviolet light in beagle dogs is located in the investigator's brochure.
Next, the portion of the subject's blood, recipient's blood, or the donor's blood to which the photoactive compound has been administered is treated by subjecting the portion of the blood to photopheresis using ultraviolet light. The photopheresis treatment may be carried out using long wavelength ultraviolet light (UVA) at a wavelength within the range of 320 to 400 nm. Such a range is not limiting, however, but is merely provided as an example. The exposure to ultraviolet light during the photopheresis treatment may have a duration of sufficient length to deliver, for example, about 1-2 J/cm2to the blood.
The photopheresis step is carried out in vitro by installingirradiation chamber700 intophotoactivation chamber750 of permanent tower system2000 (FIGS. 17 and 18). In one embodiment, when the photopheresis step is carried out in vitro, at least a fraction of the treated blood is returned to the subject, recipient, or donor. The treated blood or the treated enriched leukocyte fraction (as the case may be) may then be administered back to the subject, recipient, or donor.
The photopheresis process consists of three phases including: 1) the collection of a buffy-coat fraction (leukocyte-enriched), 2) irradiation of the collected buffy coat fraction, and 3) reinfusion of the treated white blood cells. This process will be discussed below in greater detail. Generally, whole blood is centrifuged and separated incentrifuge bowl10. A total of approximately 240 ml of buffy coat and 300 ml of plasma are separated and saved for UVA irradiation.
The collected plasma and buffy coat are mixed with heparinized normal saline and UVADEX®. (water soluble 8-methoxypsoralin). This mixture flows in a 1.4 mm thick layer through the irradiation chamber of the present invention. Theirradiation chamber700, is inserted inphotoactivation chamber750 oftower system2000 between two banks of UVA lamps of the PHOTOSETTE® (FIG. 15). PHOTOSETTE® UVA lamps irradiate both sides of this UVA-transparent irradiation chamber700, permitting exposure to ultraviolet A light, yielding an average exposure per lymphocyte of 1-2 J/cm2. Following the photoactivation period, the cells are removed from theirradiation chamber700.
In a preferred embodiment of the present invention the cells are removed by the action of gravity and any cells remaining in the chamber are displaced from the chamber with additional fluid selected from the group consisting of saline, plasma, and combinations thereof. For patients who are small such as children (e.g. under 30 kg) or patients whose vascular system is easily overloaded with fluids the amount of additional fluid used to was the irradiation chamber will preferably be not more than 2× the volume of the chamber, preferably not more than 1× the volume of the chamber, more preferably not more than 0.5× the volume of the chamber 0.25× the volume of the chamber. The treated cells volume is reinfused to the patient.
For a description of similar photopheresis systems and methods, see U.S. patent application Ser. No. 09/480,893, which is expressly incorporated herein by reference. Also useful herein are the methods and systems described in U.S. Pat. Nos. 5,951,509; 5,985,914; 5,984,887, 4,464,166; 4,428,744; 4,398,906; 4,321,919; PCT Publication Nos. WO 97/36634; and WO 97/36581, all of which are entirely expressly incorporated herein by reference.
The effective amount of light energy that is delivered to the biological fluids may be determined using the methods and systems described in U.S. Pat. No. 6,219,584, which is entirely expressly incorporated herein by reference. Indeed, the application of ECP to the various diseases described herein may require an adjustment of the amount of light energy to optimize the treatment process.
Furthermore, the photosensitizing agent used in the ECP process may be removed prior to returning the treated biological fluid to the patient. For example, Methoxsalen (UVADEX®) is utilized in the ECP process. Methoxsalen belong to a group of compounds known as psoralens. The exposure to methoxsalen or other psoralens may cause undesirable effects on the subject, recipient, or donor such as phototoxicity or other toxic effects associated with psoralen and their decomposition products. Therefore, the psoralen, psoralen derivatives, or psoralen decomposition products that may remain in the biological fluid may be removed after UV exposure. A process for the removal of psoralen biological fluids is described in U.S. Pat. No. 6,228,995, which is entirely expressly incorporated herein by reference.
C. Centrifuge Bowl
In a specific embodiment, the present invention relates to methods and apparatus that separate fluid components, such as, for example, the components of a biological fluid by density or weight. Biological fluids encompass fluids that comprise, exist in, or are used in, or delivered to living organisms. Indeed, biological fluids may comprise bodily fluids and their components, such as blood cells, plasma, and other fluids that comprise biological components, including living organisms such as bacteria, cells, or other cellular components. Biological fluids may also comprise whole blood or specific whole blood components, including red blood cells, platelets, white blood cells, and precursor cells. In particular, it may be desirable to remove blood from a patient for treatment, such as for example, extracorporeal treatment. It is to be understood, however, that the present invention is adaptable to use with various centrifugal processing apparatus, and the specific example given herein is merely for illustrative purposes. Other uses for the separation techniques and apparatus may include other medical processes such as dialysis, chemotherapy, platelet separation and removal, and separation and removal of other specific cells. Additionally, the present invention may be used to separate other types of fluids that include a wide variety of non-medical uses, such as, for example, oil and fluid component separation. All components used in the present invention should not adversely affect biological fluids or render them unsuitable for their intended uses, such as those described herein and may be made of any suitable material compatible with uses described herein including, but not limited to plastics, such as polycarbonate, methyl methacrylate, styrene-acrylonitrile, acrylic, styrene, acrylonitrile or any other plastic. Where parts of the present invention are indicated to be attached together and form a fluid tight seal any appropriate conventional means of joining the parts may be used including but not limited to, adhesives, ultrasonic welding or RF welding.
The present invention has several advantages over centrifuges what use conventional Latham bowl. The Latham bowl in the UVAR® XTS™ system has one inlet port that allows whole blood to come into the bowl and one outlet port that allows plasma and buffy coat to come out. Having only two ports limits the volume of buffy coat that can be collected per cycle. Each cycle involves filling the bowl with whole blood; 2) spinning the bowl to separate whole blood into plasma, buffy coat, and red blood cells; 3) collecting buffy coat for treatment, 4) bringing the bowl to rest; and 5) returning collected plasma and red blood cells. This buffy coat collection method may be characterized as being “batch-like” as the volume of buffy coat required for irradiation treatment can only be collected after several cycles of buffy coat collection. The limited volume of collected buffy coat per cycle results from the accumulated red blood cells remained inside the bowl. Thus the accumulated red blood cells that can only be emptied at the end of a buffy coat collection cycle is an inherent limitation of the Latham Bowl.
The bowl of the instant invention has three separate fluid conduits that can be used as an inlet port and two outlet ports. The additional fluid conduits allows for 1) reduce patient treatment time by having continuous spinning during the entire buffy coat collection process without having to stop spinning the bowl for removal of accumulated red blood cells; 2) treat small blood volume patients; by having collected red blood cells returned to patients continuously, these patients may be more amenable to medical treatments requiring the use of the buffy coat or fractions thereof such as extracorporeal photopheresis; 3) better separation of different components of fractions of cells within the buffy coat due to the increased spinning or rotation time and 4) the ability to separate high density red blood cells fractions from whole blood. This centrifuge bowl also provides the opportunity for reduced treatment time for any medical procedure requiring buffy coat fractions to be collected from patients that are substantially free of red blood cells, such as extra corporeal photopheresis.
To achieve the objects in accordance with the purpose of the present invention, as embodied and broadly described herein,FIGS. 35 and 36 depict specific embodiments of the present invention. The embodiment depicted inFIG. 35 comprises acentrifuge bowl10A,conduit assembly860A,frame910A andstationary restraint918A. Thecentrifuge bowl10A is in fluid communications withexternal conduit20A ofconduit assembly860A.Lower sleeve end832A (FIG. 46) ofconnection sleeve500A is secured to bowl10A.Upper sleeve end831A ofconnection sleeve500A is secured toexternal conduit20A, connecting theexternal conduit20A to bowl10A and providing fluid communications fromexternal conduit20A to bowl10A. The fluid communications enables fluid800 to be supplied throughexternal conduit20A to thebowl10A. Similarly this fluid communications also enables separatedfluid components810 and820 to be removed frombowl10A throughexternal conduit20A.Bowl10A andframe910A are adapted to be rotated aroundcenter axis11A.
Referring toFIG. 36,bowl10A comprisesouter housing100A,connection sleeve500A,top core200A,bottom core201A, andhousing floor180A.Outer housing100A may be constructed of any suitable biocompatible material as previously described for the purpose of the illustration inFIG. 36 theouter housing100A is constructed of clear plastic so thatcores200A and201A are visible there through.Outer housing100A is attached to ahousing floor180A, which in turn comprisesprotrusions150A for lockingbowl10A into a rotational device such asrotational device900A.Bowl10A is preferably simplified in construction and is easy to manufacture by molding or other known manufacturing processes, such that it may be disposable or used for a limited number of treatments, and is most preferably capable of containing about 125 ml of fluid, such fluid possibly being pressurized. In alternative embodiments, the volume capacity of the bowl may vary depending upon the health of the patient and his or her allowable extracorporeal volume. The volume capacity of the bowl may also vary depending upon the use of the bowl or the particular treatment for which the bowl is utilized. Additionally, to avoid contamination of biological fluids, or exposure of persons involved in the processing operation to the fluids, the transfer operations are preferably carried out within a sealed flow system, possibly pressurized, preferably formed of flexible plastic or similar material which can be disposed of after each use.
As is illustrated inFIGS. 36 and 37, theouter housing100A is substantially conical having anupper housing end110A, anouter housing wall120A and a lower housing end190A.Outer housing100A may be made of plastic (such as those plastics listed previously), or any other suitable material.Upper housing end110A has anouter surface110B,inner surface110C andhousing outlet700A providing a passage between said surfaces. Preferably the upper housing will also have aneck115A formed about thehousing outlet700A. Thehousing outlet700A andneck115A are sized to allowbody830A of theconnection sleeve500A to pass through while retainingsleeve flange790A, which extends from thebody830A ofconnection sleeve500A. In one embodiment of the present invention an o-ring791A may be inserted between thesleeve flange790A andinner surface110C of thehousing end110A to ensure a fluid tight seal is provided. In an alternative embodiment of the present invention illustrated inFIG. 53, asecond sleeve flange790B extends from thebody830A ofconnection sleeve500B distal to thesleeve flange790A. Bothsleeve flange790A and790B being adapted to fit withinneck115A and retain o-ring791A therebetween. A fluid tight seal is provided in this embodiment by the o-ring contacting body830A andinner surface110C of thehousing end110A adjacent to theneck115A. However,connection sleeve500A can be secured to bowl10A by any suitable means, including for example, a lip, groove, or tight fit and adhesive with a component ofbowl10A. The outer housing wall joins theupper housing end110A and lower housing end190A. Lower housing end190A is attached to ahousing floor180A of greater diameter thanupper end110A.Housing floor180A is adapted to mate with the lower housing end190A and provide a fluid tight seal therewith. Any conventional means may be used to secure the lower housing end190A to thehousing floor180A, including but not limited to, adhesives, ultrasonic welding or RF welding.Housing floor180A may have anindentation185A that is used to collectdenser fluid810. The diameter ofouter housing100A increases from upper housing end110A to lower housing end190A.
Outer housing100A is adapted to rotatably connect to a rotational device900 (FIG. 35), such as for example, a rotor drive system or arotating bracket910. The rotatable connection may, for example, be a bearing that allows free rotation ofbowl10A.Outer housing100A preferably has a locking mechanism. The locking mechanism may be one ormore protrusions150A designed to interact with corresponding indentations in a centrifuge container or any other suitable interconnect or locking mechanism or equivalent known in the art. The locking mechanism may also comprise a key slot160 (FIG. 51).
Referring toFIG. 37,outer housing100A and thebase180A define aninterior volume710A in whichcores200A and201A will fit whenbowl10A is assembled. When fully assembled,cores200A and201A are fully withininterior volume710A ofouter housing100A, occupying a coaxial volume ofinterior volume710A aboutaxis11A.
Referring toFIGS. 38, 40 and44, thetop core200A andbottom core201A are substantially conical and respectively have upper core ends205A,206A;outer core walls210A,211A; and lower core ends295A,296A. Thecores200A,201A occupy coaxial volumes ofinterior volume710A ofbowl10A and formingseparation volume220A betweenupper end205A andouter wall210A oftop core200A andouter wall211A and lower core end296A ofbottom core201A andouter housing100A.Separation volume220A is that space ofinterior volume710A that is betweencores200A and201A andouter housing10A.
As depicted inFIGS. 40 and 41top core200A comprises uppercore end205A and alower core end295A that are joined byouter core wall210A. Theouter core wall210A having anouter surface210B andinner wall surface210C and alower edge210D. The diameter oftop core200A preferably increases from uppercore end205A tolower core end295A. Uppercore end205A also comprises anouter surface205B and aninner surface205C. Centrally located about center axis and extending perpendicularly from theupper surface205B islumen connector481A.Lumen connector481A has atop surface482A and awall surface482B.Top surface482A has twopassages303B and325D that provide fluid communications through the uppercore end205A withsecond bowl channel410A andfirst bowl channel420A respectively.Second bowl channel410A is a conduit that has aconduit wall325A that extends perpendicularly from theinner surface481C oflumen connector481A.
As shown onFIGS. 39B, 39A and40, second bowl channel410 has fluid communication withconduit channel760A throughconduit321A having afirst end321B and asecond end321C that is adapted to fit intopassage325D oflumen connector481A. Inoperation conduit channel760A ofexternal conduit20A has fluid communication withbowl channel410A.First bowl channel420A is a second conduit that has achannel wall401A that extends substantially perpendicularly frominner surface481C of thelumen connector481A. As shown inFIGS. 39A, 39B and40,first bowl channel420A has fluid communication withconduit channel780A ofexternal conduit20A throughhollow cylinder322A having a first end322B and a second end322C adapted to fit opening303B top surface482A. As is illustrated in one embodiment of the present invention,second bowl channel410A is disposed withinfirst bowl channel420A. In an alternative embodiment of the present invention illustrated inFIG. 53,conduit wall325A may be composed ofupper part325F andlower part325G and be fused withchannel walls401A and402A.
Top surface482A also hasindentation483A which provides fluid communications withchamber740A. When assembled,chamber740A is defined by lumen mountingrecess851A less the volumes occupied byhollow cylinders321A and322A in the connection junction ofconnection sleeve500A andlumen connector481A.Chamber740A has fluid communication withconduit channel770A and withseparation volume220A nearneck115A throughindentation483A. Thusindentation483A forms a passageway for the removal of secondseparated fluid component820 throughbowl chamber740A. Optionally present on theouter surface205B are a plurality ofspacers207A which extend from the outer surface and contact theinner surface110C of the upper housing end110A to ensure fluid communications between theseparation volume220A and the passageway formed by theindentations483A.
In an alternative embodiment illustrated inFIGS. 53, 54 and55,conduits321A and322A may be affixed toopenings325D and303B in thetop surface482A of thelumen connector481A. Additionally,indentations483A may form a plurality channels in thelumen connector481A and be adapted to formchamber740B when connected toconnection sleeve500A or500B.Chamber740B is adapted to have one or more surfaces742A that can mate with themale end853A of theconnection sleeve500A (male end853A surrounds end861 ofexternal conduit20A). To facilitate the correct orientation of theconnection sleeve500A to thelumen connector481A the shape of themale end853A andchamber740B may be nonsymmetrical or as is illustrated inFIGS. 53, 54 and55 aguide855A may be provided which extends from the top surface of thelumen connector481A and is adapted to fit within opening857A of thesleeve flange790A.
Referring back toFIGS. 40, thelower core end295A comprises anupper plate299A having atop surface298A, abottom surface297A, and anedge299B that attaches and makes direct contact withlower edge210D of theouter core wall210A. Theedge299B of theupper plate299A is adapted to be joined withlower edge210D ofouter core wall210A and form a fluid tight seal therewith. Extending perpendicularly from thetop surface298A ofupper plate299A is achannel wall402A, having anupper end402B and alower end402C and surroundsopening303A which is substantially in the center ofupper plate299A. A number offins403A, attached to the outside surface ofchannel wall402A andtop surface298A, supportslumen wall402A. Thechannel wall402A is adapted to mate withchannel wall401A forming a fluid tight seal and providinglumen400A.First bowl channel420A is in fluid communications withconduit channel780A ofexternal conduit20A throughconduit322A. Opening303A provides fluid communications from lumen400A toseparation volume220A as will be further discussed.First bowl channel420A also surroundssecond bowl channel410A.
Referring toFIGS. 43A, 43B and44,bottom core201A comprises an uppercore end206A, aouter core wall211A and a lower core end296A. Theouter core wall211A having anouter surface211B, aninner wall211C andlower edge211D. The diameter ofbottom core201A preferably increases from uppercore end206A to lower core end296A.Bottom core201A also has atop surface309A and abottom surface309B.Top surface309A has anindentation186A (preferably generally circular) substantial in the center of thesurface309A of the uppercore end206A. Theindentation186A has anupper surface186B and aninner surface186C. Theupper surface186B of theindentation186A has therein anopening324D which extends through to theinner surface186C. In an alternative embodiment of the present invention illustrated inFIG. 53, theupper surface186B, may also have a recess a186D adapted to receive an o-ring and form a fluid type seal around the lower end of325B ofconduit wall325A. Extending perpendicularly frominner surface186C around saidopening324D isconduit wall324A having adistal end324B. On thetop surface309A extending from theindentation186A to theouter surface211B of theouter core wall211A are one ormore channels305A. Thetop surface309A may be horizontal or slope upward or downward fromindentation186A. Iftop surface309A slopes upward or downward fromindentation186A tocore end206A, one skilled in the art would be able to adjust the shapes ofupper plate299A and uppercore end295A accordingly.Channels305A may have an even depth through out the length of thechannel305A. However,channel305A may slope downward or upward radially from the center. One skilled in the art would see that iftop surface309A slopes upward or downward andchannel305A has a constant depth, then channel305A slopes upward or downward accordingly.
Referring toFIGS. 38, thebottom surface297A ofupper plate299A is in direct contact with thetop surface area309A ofbottom core201A when completely assembled. This contact forms a fluid tight seal between the two surface areas forming anopening305B from theindentation186A to channel305A. Asecond opening305C fromchannel305A is formed in theouter surface211B ofouter core wall211A. Theopening305B provides fluid communications fromindentation186A throughchannel305A andopening305C toseparation volume220A (FIGS. 38 and 40). Thus fluid800 flows throughconduit channel780A and subsequently passes throughfirst bowl channel420A. Fromfirst bowl channel420A, fluid800 then goes to throughchannel305A to theseparation volume220A.
Referring toFIGS. 43A and 44, the lower core end296A has alower plate300A, which has atop surface300B, abottom surface300C andouter edge300D. Extending from thebottom surface300C of the lower plate300 are one ormore protrusions301A. Theouter edge300D is adapted to be attached to thelower edge211D of theouter core wall211A and provide a fluid tight seal therewith. Positioned abovehousing floor180A,lower plate300A is circular and curves upward radially from its center (illustrated inFIG. 44). Alternatively,lower plate300A can be flat. As shown inFIG. 38 when positioned abovehousing floor180A, avolume220C exists betweenlower plate300A andhousing floor180A. Thisvolume220C is in fluid communication withseparation volume220A.Lower plate300A may be made of plastic or any other suitable material. Additionally, extending substantially perpendicularly from thelower surface300C oflower plate300A is aconduit320A.Conduit320A has afirst end320B that extends into thespace220C betweenlower plate300A andhousing floor180A and asecond end320C that extends above thetop surface300B oflower plate300A. The diameter ofconduit320A is adapted to have a tight fit withconduit wall end324B. The volume insideconduit walls324A and325A comprises alumen400B. The volume defined bylower plate300A,inner surface211C, and ceiling253A ofbottom core201A, excludingsecond bowl channel410A, may comprise of air or a solid material (SeeFIGS. 43B and 44).
In an alternative embodiment of the present invention as illustrated inFIG. 53,support walls405A and407A may be optionally present.Support wall405A extends perpendicularly frombottom surface309B.Support wall407A extends perpendicularly from thetop surface300B oflower plate300A and connects withsupport wall405A when thebottom core201A is assembled.Conduit wall324A may be connected toconduit320A to form a fluid tight seal andconduits324A,320A may be fused respectively withsupports walls405A and407A. Additionally present extending from thebottom surface300C oflower plate300A are one ormore orientation spacers409A that mate withinindentation185A.
As will be readily apparent to one of ordinary skill in the art, thebowl10A will need to be balanced aboutcenter axis11A. Accordingly, weights may be added as part of the device as is appropriate to facilitate the balancing of thebowl10A such asweight408A illustrated inFIG. 53.
Referring toFIG. 38,bowl10A is adapted so thatouter housing100A,cores200A and201A,lower plate300A andupper plate299A,housing floor180A,external conduits20A andconnection sleeve500A, andlumens400A and400B are in connection and rotate together.Housing floor180A ofouter housing100A comprisesrecesses181A on its top surface and these recesses are shaped to fitprotrusion301A oflower plate300A. As shown,lower plate300A hasround protrusion301A on itsbottom surface300C to restrict movement oflower plate300A with respect tohousing floor180A. When assembled, eachsingle protrusion301A on the bottom surface oflower plate300A forms a tight fit withrecess181A onhousing floor180A. Thus, whenouter housing100A is rotated,external conduit20A andconnection sleeve500A,top core200A,upper plate299A,bottom core201A,lower plate300A,housing floor180A, andlumens400A and400B will rotate therewith.
As illustrated inFIG. 38lumen400A allowswhole blood800 to come intobowl10A via afirst bowl channel420A.First bowl channel420A provides a passageway for inflow offluid800 throughlumen400A to indention186A and then to theseparation volume220A throughchannel305A.Lumen400A is located insidetop core200A.Lumen400A has a height from upperlumen end480A andlower lumen end402C.Lumen400A is formed by the connection ofchannel wall401A extending from theinner surface481C oflumen connector481A andchannel wall402A extending from thetop surface298A ofupper plate299A.Channel wall401A is supported by a plurality offins251A which are attached to theinner wall surface210C of theouter core wall210A andinner surface205C of the uppercore end205A, andchannel wall402A is supported by a plurality offins403A (FIG. 40). It can readily be seen that height oflumen400A can be adjusted by changing the sizes and shapes ofcore200A,channel wall401A,channel wall402A,conduit wall325A, and the height ofconduit wall324A.
As illustrated inFIG. 38,lumen400A, from upper lumen end480A to lowerlumen end402C, encloses aninner lumen400B. Lowerlumen end402C has anopening303A which is in fluid communication withseparation volume220A through a number ofchannel305A. In the illustratedembodiment lumen400A comprisesfirst bowl channel420A.Second bowl channel410A is located insidefirst bowl channel420A of thetop core200A and is enclosed therein fromlumen end480A and to lumen402C. Furthermore,second bowl channel410A forms a passageway throughlumen400B from belowlower plate300A for the removal of a firstseparated fluid component810 that gathers inindentation185A ofhousing floor180A.Second bowl channel410A extends fromhousing floor180A ofouter housing100A throughlumen400B and toconduit channel760A ofexternal conduit20A.
ReferringFIG. 38 (shown withoutconduit321C),inner lumen400B allowsred blood cells810 to exitbowl10A via asecond bowl channel410A that provides fluid communication from the housing floor aboveindentation185A toopening324E.Inner lumen400B has an upper conduit end325C and a lower conduit end324B and comprises twoconduit walls324A and325A which are connected in a fluid tight manner and formsecond bowl channel410A that has a smaller diameter than and is separate and distinct fromfirst bowl channel420A.Conduit wall325A is supported by afin251A that extends throughchannel wall401A and attaches to conduit wall325A. Unlikelumen400A which has one end nearindentation186A,lumen400B extends beyondindentation186A and throughbottom plate300A. Thefirst conduit wall325A has an upper end325C which has anopening325D on thetop surface482A oflumen connector481A and alower end325B having anopening325E adapted to fit tightly withupper end324C ofconduit wall324A.Upper end324C ofconduit wall324A is higher thanindentation186A and has anopening324D.Conduit wall324A also has endlower end324B and is supported by a plurality offins252A.Lower end324B having opening325E is adapted to connect toconduit320A havingopening302A located near the center oflower plate300A. The connection ofopenings325E and302A provide fluid communication betweenlumen400B and thespace220C betweenlower plate300A andhousing floor180A. Thespace220C betweenlower plate300A andhousing floor180A in turn has fluid communication withseparation volume220A.
Conduit320A provides a tight fit withlower end324B, providing support forsecond bowl channel410A. Eachbowl channel420A and410A may be made of any type of flexible or rigid tubing (such as medical tubing) or other such device providing a sealed passageway, possibly for pressurized or unpressurized fluid flow, and which preferably can be disposable and sterilizable, i.e., of simple and efficient manufacture.
1. Drive Tube
As illustrated inFIGS. 39A and 39B,conduit assembly860A is attached to bowl10A viaconnection sleeve500A which is attached onto thefirst end861A ofexternal conduit20A having afirst conduit channel780A, asecond conduit channel760A, and athird conduit channel770A. Each conduit channel has fluid communication with afirst bowl channel420A, asecond bowl channel410A, and abowl chamber740A. The three conduit channels are equally spaced1200 apart and equal in diameter inexternal conduit20A (SeeFIG. 50). When fluidly connect toexternal conduit20A andbowl10A,conduit channel780A is fluidly connected withfirst bowl channel420A for inflowingfluid800 fromexternal conduit20A intobowl10A for separation. Similarly,second conduit channel760A fluidly connects tosecond bowl channel410A for removing first separatedfluid component810 frombowl10A intoexternal conduit20A. Finally,third conduit channel770A connects to bowlchamber740A for removing secondseparated fluid component820 frombowl10A.
As is illustrated inFIG. 45,external conduit20A has aconnection sleeve500A on thefirst end861A and ananchor sleeve870A on thesecond end862A ofexternal conduit20A. Optionally present between theconnection sleeve500A and theanchor sleeve870A onexternal conduit20A are a first shoulder882 and a second shoulder884 which extend perpendicularly from theexternal conduit20A and are of a larger diameter. Between theconnection sleeve500A andanchor sleeve870A (or if present the first and second shoulder882,884) are a first and second bearing rings871A and872A.External conduit20A,anchor sleeve870A, and connection sleeve may be prepared from the same or different biocompatible materials of suitable strength and flexibility for use in this type of tubing in a centrifuge (one such preferred material is HYTREL®). Theconnection sleeve500A and theanchor sleeve870A may be attached through any suitable means such as adhesives, welding etc., however, for ease of manufacture it is preferred that theconnection sleeve500A and theanchor sleeve870A be overmolded to theexternal conduit20A.
Referring toFIGS. 45, 48 and49anchor sleeve870A comprises abody877B having afirst anchor end873A andsecond anchor end874A.Anchor sleeve870A is attached to second conduit end862A ofexternal conduit20A (preferably by overmolding) and increases in diameter fromfirst collar873A to thecollar874A. Spaced distally fromsecond end874A is acollar886A, which extends perpendicularly frombody877B and of a larger diameter than thebody877B of theanchor sleeve870A. A plurality ofribs877A having afirst rib end877B between thecollar886A andsecond anchor end873A and asecond rib end877C extending beyond thefirst anchor end873A are attached to thebody877B. The second rib ends877C are joined together by aring880A, which is also attached toexternal conduit20A. Theribs877A run parallel to theexternal conduit20A and are preferably placed over the region whereconduit channels760A,770A, and780A, are closest to the surface of theexternal conduit20A (FIG. 50). The regions where theconduit channels760A,770A and780A are closest to the outside diameter ofexternal conduit20A unless reinforced tend to fail during high speed rotation. Having ribs parallel with the conduit channels beyond theanchor sleeve end873A provides reinforcement to this region and prevents conduit failure at high speed rotation. In one aspect, the ribs prevent the buckling of theexternal conduit20A in this region and act as structural elements to transfer the torsional stress to theanchor sleeve870A.
Connection sleeve500A comprisesbody830A having anupper sleeve end831A andlower sleeve end832A (FIGS. 46 and 47).Lower sleeve end832A hassleeve flange790A and a plurality ofprotrusions843A, which are sized to engageindentations484A on thewall surface482A oflumen connector481A. When thebowl10A is assembled, a fluid tight seal may be provided by placing o-ring791A aroundbody830A and compressing the o-ring791A betweenflange790A andhousing100A.Upper sleeve end831A is adapted to be secured toexternal conduit20A. Referring toFIG. 46, 39A and39B,connection sleeve500A is secured to bowl10A by means ofsleeve flange790A and is adapted to fluidly connectconduit channels780A,760A,770A ofexternal conduit20A to bowlchannels420A and410A, andchamber740A ofbowl10A. When assembled,connection sleeve500A is mounted tolumen connector481A (FIGS. 39A and 39B).
Connection sleeve500A preferably increases in diameter from upper sleeve end831A tolower sleeve end832A and is overmolded tofirst conduit end861A ofexternal conduit20A.Connection sleeve500A connectsbowl10A toexternal conduit20A without use of a rotatable seal, which would otherwise normally be located betweenbowl10A andconnection sleeve500A. The seal-less connection betweenbowl10A andconnection sleeve500A may occur as explained above or alternatively through use of, for example, an0-ring, a groove, or lip, grommet-type connection, welding, or a tight fit with or without adhesive in eitherbowl10A orconnection sleeve500A.
As illustrated inFIG. 46 and39B,sleeve flange790A has abottom surface847A that contacts withtop surface482A oflumen connector481A forming a tight seal. However,lumen connector481A has a plurality ofindentation483A that provides for fluid communication betweenseparation chamber220A andbowl chamber740A, which, in turn has fluid communication withconduit channel770A.Bowl chamber740A is defined by lumen mountingrecess851A andtop surface482A oflumen connector481A, excluding the space occupied byhollow cylinders321A and322A. A plurality ofprotrusions843A on thebottom surface847A ofsleeve flange790A engages and slides intoindentations484A on thewall surface482B oflumen connector481A, thus providing a tight fit.
Connection sleeve500A helps to secureexternal conduit20A to bowl10A, thus fluidly connectingexternal conduit20A to bowl10A. This fluid connection enables fluid800 to be supplied throughexternal conduit20A to bowl10A. Similarly, this fluid connection also enables separated fluid components b,820 to be removed frombowl10A throughexternal conduit20A.
External conduit20A has an approximately constant diameter which helps to reduce the rigidity. An excessively rigidexternal conduit20A will heat up and fail more quickly. Additionally, a constant diameter conduit is cheap/easy to manufacture, allows easy experimentation withconnection sleeve500A andanchor sleeve870A sizes, and allows bearing rings871A,872A to be easily slid thereon. Preferably the movement ofbearings871A and872A will be constrained by first andsecond shoulders882A and884A.External conduit20A may be made of any type of flexible tubing (such as medical tubing) or other such device providing a sealed passageway for the flow of fluids, which may be pressurized, into or out of a reservoir of any sort, and which preferably can be disposable and sterilizable.
II. Permanent Tower System
FIG. 17 illustratestower system2000.Tower system2000 is the permanent (i.e., non-disposable) piece of hardware that receives the various devices ofphotopheresis kit1000, such as,cassette1100,irradiation chamber700, and centrifuge bowl10 (FIG. 1).Tower system2000 performs the valving, pumping, and overall control and drive of fluid flow throughdisposable photopheresis kit1000.Tower system2000 performs all of the necessary control function automatically through the use of a properly programmed controller, for example a processor or IC circuit, coupled to all of the necessary components. While a new disposable kit must be discarded after each photopheresis therapy session,tower system2000 is used over and over again.Tower system2000 can be modified to perform a number of extracorporeal blood circuit treatments, for example apheresis, by properly programming the controller or by changing some of its components.
Tower system2000 has a housing having anupper portion2100 and abase portion2200.Base portion2200 has a top2201 and a bottom2202.Wheels2203 are provided at or near thebottom2202 ofbase portion2200 so thattower system2000 is mobile and can easily be moved from room to room in a hospital setting. Preferably, thefront wheels2203 are pivotable about a vertical axis to allow ease in steering andmaneuvering tower system2000.Top2201 ofbase portion2200 has atop surface2204 havingcontrol deck1200, best illustrated inFIG. 22, built therein (seeFIG. 22). InFIG. 17,cassette1100 is loaded ontocontrol deck1200.Base portion2200 also has hooks (not illustrated), or other connectors, to hangplasma collection bag51 andtreatment bag50 therefrom. Such hooks can be located anywhere ontower system2000 so long as their positioning does not interfere with the functioning of the system during therapy.Base portion2200 has photoactivation chamber750 (FIG. 18) located behinddoor751. Additional hooks (not illustrated) are provided ontower system2000 for hanging saline and anticoagulant bags. Preferably, these hooks are located onupper portion2100.
Photoactivation chamber750 (FIG. 18) is provided inbase portion2200 oftower system2000 between top2201 and bottom2202 behinddoor751.Door751 is hingedly connected tobase portion2200 and is provided for access tophotoactivation chamber750 and to allow the operator to closephotoactivation chamber750 so that UV light does not escape into the surrounding during treatment.Recess752 is provided to allowtubes1112,1117 (FIG. 1) to pass intophotoactivation chamber750 whenirradiation chamber700 is loaded and whendoor751 is closed. The photoactivation chamber is discussed in detail below with respect toFIGS. 16 and 18.
Upper portion2100 is located atopbase portion2200. Centrifuge chamber2101 (FIG. 19) is located inupper portion2100 behindcentrifuge chamber door2102.Centrifuge chamber door2102 has awindow2103 so an operator can see incentrifuge chamber2101 and monitor for any problems.Window2103 is constructed with glass thick enough to withstand any forces that may be exerted on it from an accident during centrifugation which can rotate the centrifuge bowl at speeds greater than4800 RPMs. Preferably,window2103 is constructed of shatter-proof glass.Door2102 is hingedly connected toupper portion2100 and has an automatic locking mechanism that is activated by the system controller during system operation.Centrifuge chamber2101 is discussed below in more detail with respect toFIG. 19.
Preferably,deck1200 is located ontop surface2204 ofbase portion2200 at or near the front ofsystem tower2000 whileupper portion2100 is extending upward frombase portion2200 near the rear oftower system2000. This allows the operator easy access to controldeck1200 while simultaneously affording the operator access tocentrifuge chamber2101. By designingtower system2000 to have thecentrifuge chamber2101 in theupper portion2100 and having thephotoactivation chamber750 anddeck1200 inbase portion2200, an upright configuration is achieved. As such,system tower2000 has a reduced footprint size and takes up a reduced amount of valuable hospital floor space. The height ofsystem tower2000 remains below sixty inches so that one view is not obstructed when transporting the machine around the hospital form the rear. Additionally, havingdeck1200 in a fairly horizontal position will provide the operator with a place to set devices ofphotopheresis kit1000 during the loading of other devices, facilitating easy loading.Tower system2000 is robust enough to withstand forces and vibrations brought on by the centrifugation process.
Amonitor2104 is provided oncentrifuge chamber door2102 abovewindow2103.Monitor2104 has adisplay area2105 for visually displaying data to an operator, such as, for example, user interfaces for data entry, loading instructions, graphics, warnings, alerts, therapy data, or therapy progress.Monitor2104 is coupled to and controlled by the system controller. A datacard receiving port2001 is provided on a side ofmonitor2104. Datacard receiving port2001 is provided to slidably receivedata card1195 which is supplied with each disposable photopheresis kit1000 (FIG. 1). As mentioned above,data card1195 can be pre-programmed to store serve a variety of data to supply to the system controller oftower system2000. For example,data card1195 can be programmed to relay information so that the system controller can ensure: (1) that the disposable photopheresis kit is compatible with the blood drive equipment into which it is being loaded; (2) that the photopheresis kit is capable of running the desired treatment process; (3) that the disposable photopheresis kit is of a certain brand name or make. Datacard receiving port2001 has the necessary hardware and circuitry to both read data from, and write data to,data card1195. Preferably, datacard receiving port2201 will record treatment therapy data todata card1195. Such information can include for example, collection times, collection volumes, treatment times, volumetric flow rates, any alarms, malfunctions, disturbances in the process, or any other desired data. While datacard receiving port2001 is provided onmonitor2104, it can be located anywhere ontower system2000 so long as it is coupled to the system controller or other appropriate control means.
A. Photoactivation Chamber for Receiving Irradiation Chamber
Referring now toFIGS. 16 and 18,photoactivation chamber750 is illustrated in cross section.Photoactivation chamber750 is formed byhousing756.Housing756 fits withinbase portion2200 oftower system2000 behind door751 (FIG. 17).Photoactivation chamber750 has a plurality ofelectrical connection ports753 provided onback wall754.Electrical connection ports753 are electrically coupled to a source of electrical energy.Photoactivation chamber750 is designed to receive UVA light assembly759 (FIG. 16). When fully loaded intophotoactivation chamber750, electrical contacts (not illustrated) located oncontact wall755 of UVAlight assembly759 form an electrical connection withelectrical connection ports753. This electrical connection allows electrical energy to be supplied toUVA lamps758 so that they can be activated. Preferably, three electrical connection ports are provided for each set ofUVA lamps758. More preferably, UVAlight assembly759 has two sets ofUVA lamps758 forming a space whichirradiation chamber700 can be inserted. The supply of electrical energy toUVA lamps758 is controlled by the properly programmed system controller using a switch.UVA lamps758 are activated and deactivated as necessary by the controller during the photopheresis therapy session.
Vent hole757 is provided in the top ofhousing756 nearback wall754 ofphotoactivation chamber750.Vent hole757 connects to ventduct760 which leads out of the back oftower system2000. When heat generated byUVA lamps758 builds up inphotoactivation chamber750 during a treatment therapy, this heat escapesphotoactivation chamber750 viavent hole757 and ventduct760. The heat exitstower system2000 throughtower housing hole761 located in the rear oftower system2000, away from the patient and the operator.
Photoactivation chamber750 further comprisestract762 for receivingirradiation chamber700 and holding irradiation in an upright position betweenUVA lamps758.Tract762 is at or near the bottom ofphotoactivation chamber750. Preferably, a leak detector circuit763 is provided belowtract762 to detect any fluidleaks irradiation chamber700 during, before, or after operation.Leak detector circuit762 has two electrodes patterned in a U shape located on an adhesive backed flex circuit. The electrodes are designed to allow for application of a short circuit to test for discontinuities. One end of each electrode goes to an integrated circuit while the other end of each electrode is tied to a solid-state switch. The solid-state switch can be used to check for continuity of the electrodes. By closing the switch the electrodes are shorted to one another. The integrated circuit then detects the short. Closing the switch causes a situation equivalent to the electrodes getting wet (i.e., a leak). IN If the electrodes are damaged in any way, the continuity check will fail. This is a positive indication that the electrodes are not damaged. This test can be performed each time at system start-up or periodically during normal operation to ensure thatleak detection circuit762 is working properly.Leak detection circuit762 helps ensure that leaks do not go unnoticed during an entire therapy session because the leak detection circuit is damaged. An electrical schematic ofleak detector circuit762 is provided inFIG. 20.
B. Centrifuge Chamber
FIG. 19 illustratescentrifuge chamber2101 in cross section with the housing oftower system2000 removed. Rotational device900 (also in cross-section) capable of utilizing 1-omega 2-omega spin technology is positioned withincentrifuge chamber2101.Rotational device900 includes arotating bracket910 and abowl holding plate919 for rotatably securing centrifuge bowl10 (FIG. 1).Housing2107 ofcentrifuge chamber2101 is preferably made of aluminum or some other lightweight, sturdy metal. Alternatively, other rotational systems may be used withintower system2000 such as that described in U.S. Pat. No. 3,986,442, which is expressly incorporated herein by reference in its entirety.
Leak detection circuit2106 is provided onback wall2108 ofhousing2107.Leak detection circuit2106 is provided to detect any leaks withincentrifuge bowl10 or the connecting tubes during processing.Leak detection circuit2106 is identical to leakdetector circuit762 described above. An electrical schematic ofleak detection circuit2106 is provided inFIG. 21.
C. Fluid Flow Control Deck
FIG. 22 illustratescontrol deck1200 of tower system2000 (FIG. 17) without acassette1100 loaded thereon.Control deck1200 performs the valving and pumping so as to drive and control fluid flow throughoutphotopheresis kit1000. Preferably,deck1200 is aseparate plate1202 that is secured tobase portion2200 oftower system2000 via screws or other securing means, such as, for example, bolts, nuts, or clamps.Plate1202 can be made of steel, aluminum, or other durable metal or material.
Deck1200 has five peristaltic pumps,whole blood pump1301,return pump1302,recirculation pump1303,anticoagulant pump1304, and redblood cell pump1305 extending throughplate1202. Pumps1301-1305 are arranged onplate1202 so that whencassette1100 is loaded ontodeck1200 for operation, pump loop tubes1120-1124 extend over and around pumps1301-1305 (FIG. 25).
Airbubble sensor assembly1204 andHCT sensor assembly1205 are provided onplate1202. Airbubble sensor assembly1204 has threetrenches1206 for receivingtubes1114,1106, and1119 (FIG. 25). Airbubble sensor assembly1204 uses ultrasonic energy to monitortubes1114,1106, and1119 for differences in density that would indicate the presence of air in the liquid fluids normally passing therethrough.Tubes1114,1106, and1119 are monitored because these lines go to the patient. Airbubble sensor assembly1204 is operably coupled and transmits data to the system controller for analysis. If an air bubble is detected, the system controller will shut down operation and prohibit fluid flow into the patient by occludingtubes1114,1106, and1109 by moving compression actuators1240-1242 to a raised position, thereby compressingtubes1114,1106, and1119 againstcassette1100 as discussed above and/or shutting down the appropriate pump.HCT sensor assembly1205 hastrench1207 for receivingHCT component1125 oftube1116.HCT sensor assembly1205 monitorstube1116 for the presence of red blood cells by using a photoelectric sensor.HCT sensor assembly1205 is also operably coupled to and transmits data to the system controller. UponHCT sensor assembly1205 detecting the presence of red blood cells intube1116, the system controller will take the appropriate action, such as stopping the appropriate pump or activating one of compression actuators1243-1247, to stop fluid flow throughtube1116.
Deck1200 also has five compression actuators1243-1247 and three compression actuators1240-1242 strategically positioned onplate1202 so that whencassette1100 is loaded ontodeck1200 for operation, each of compression actuators1240-1247 are aligned withcorresponding apertures1137 and1157. Compression actuators1240-1247 can be moved between a lowered position and a raised position. As illustrated inFIG. 22, compression actuators1243-1247 are in the lowered position and compression actuators1240-1242 are in the raised position. When in a raised position, and whencassette1100 is loaded ontodeck1200 as illustrated inFIG. 25, compression actuators1240-1247 will extend through the correspondingapertures1137 or1157 and compress the portion of flexible tubing that is aligned with that aperture, thereby pinching the flexible tube shut so that fluid can not pass. When in the lowered position, compression actuators1240-1247 do not extend throughapertures1137 and1157 and thus do compress the flexible tubing.
Compression actuators1243-1247 are spring retracted so that their default position is to move to the lowered position unless activated. Compression actuators1243-1247 are independently controlled and can be raised r lowered independent of one another. Compression actuators1240-1242 on the other hand are coupled together. As such, when one compression actuator1240-1242 is lowered or raised, the other two compression actuators1240-1242 are also lowered in raised accordingly. Additionally, compression actuators1240-1242 are spring loaded so that their default position is to move to the raised position. Thus, if the system loses power during a therapy session, compression actuators1240-1242 will automatically move to the raised position, occludingtubes1114,1106, and1119 and preventing fluids from entering or leaving the patient.
Referring now toFIGS. 23 and 24,deck1200 further includessystem controller1210,cylinder assembly1211,manifold assemblies1213,pump cable1215, pumpmotor cable1216, andtiming belt assembly1217.System controller1210 is a properly programmed integrated circuit that is operably coupled to the necessary components of the system to perform all of the functions, interactions, decisions, and reaction discussed above and necessary to perform a photopheresis therapy according to the present invention.Cylinder assembly1211 couples each of compression actuators1240-1247 to a pneumatic cylinder.Air ports1212 are provided on the various elements ofdeck1200 as necessary to connect air lines to the devices and the appropriate one ofmanifolds1213. As such, air can be provided to the devices as necessary to actuate the necessary component, such as compression valves1240-1247. All of these functions and timing are controlled bysystem controller1210. Timingbelt assembly1217 is used to coordinate the rotation ofrotating clamps1203. Finally,plate1202 includes a plurality ofholes1215,1219,1220,1221, and1218 so that the various components ofdeck1200 can be properly loaded into and so thatdeck1200 can be secured totower system2000. Specifically, pumps1301-1305 fit intoholes1314,HCT sensor assembly1205 fits intohole1220, airbubble detector assembly1204 fits intohole1219, compression actuators1240-1247 extend throughholes1218, and bolts extend throughholes1221 to securedeck1200 to towerassembly2000.
1. Cassette Clamping Mechanism
Referring now toFIGS. 22 and 25, the method by whichcassette1100 is loaded and secured todeck1200 will now be discussed. In order forsystem2000 to perform a photopheresis therapy,cassette1100 must be properly loaded ontodeck1200. Because of the compression actuator valving system incorporated in the present invention, it is imperative thatcassette1100 be properly secured todeck1200 and not shift or become dislodged when compression actuators1240-1247 occlude portions of the flexible tubing by compressing the flexible tubing againstcover1130 of cassette1100 (FIG. 3). However, this requirement competes with the desired goals of ease inloading cassette1100 ontodeck1200 and reducing operator errors. All of these goals are achieved by the below described cassette clamping mechanism.
In order to facilitate clamping ofcassette1100 todeck1200,deck1200 is provided with twocatches1208 and tworotating clamps1203 and1223.Catches1208 have aslot1228 near the middle of the top plate.Catches1208 are secured toplate1202 at predetermined positions so that the spacing between them is substantially the same as the spacing betweentabs1102 and1103 on cassette1100 (FIG. 2). Rotatingclamps1203 and1223 are illustrated in a closed position. However, rotatingclamps1203 and1223 can be rotated to an open position (not illustrated) manually or through the automatic actuation of a pneumatic cylinder. Rotatingclamps1203 and1223 are spring loaded by torque springs so as to automatically return to the closed position when additional torque is not being applied. Rotatingclamps1203 and1223 are linked together by timing belt assembly1217 (FIG. 24).
Referring now toFIG. 23,timing belt assembly1217 comprisestiming belt1226,torque spring housings1224, andtension assembly1225. Timingbelt assembly1217 coordinates the rotation ofrotational clamps1203 and1223 so that if one is rotated, the other also rotates in the same direction and the same amount. In other words,rotational clamps1203 and1223 are coupled.Tension assembly1217 ensures thattiming belt1226 is under sufficient tension to engage and rotate therotational clamp1203 or1223 that is being coordinated.Torque spring housings1224 provide casings for the torque springs that torquerotational clamps1203 and1223 to the closed position.
Referring back toFIGS. 22 and 25, when loadingcassette1100 ontodeck1200,cassette1100 is placed at an angle todeck1200 andtabs1102 and1103 (FIG. 2) are aligned with catches1208.Cassette1100 is moved so thattabs1102 and1103 slidably insert into catches1208.Rotational clamps1203 and1223 are in the closed position at this time. The rear of the cassette1100 (i.e. the side opposite thetabs1102 and1103) contactsrotational clamps1203 and1223 astabs1102 and1103 are being inserted incatches1108. As force is applied downward oncassette1100,rotational clamps1103 and1123 will be rotated to the open position, allowing the rear ofcassette1100 to move downward to a position belowledges1231 ofrotational clamps1203 and1223. Oncecassette1100 is in this position, therotational clamps1203 and1223 spring back from the force applied by the torque springs and rotate back to the closed position, lockingcassette1100 in place. When in the locked position,cassette1100 can resist upward and lateral forces.
To removecassette1110 after the therapy session is complete,rotational clamps1203 and1223 are rotated to the open position either manually or automatically. Automatic rotation is facilitated by an air cylinder that is coupled to an air line andsystem controller1210. Oncerotational clamps1203 and1223 are in the open position,cassette1100 is removed by simple lifting and slidingtabs1102 and1103 out ofcatches1208.
2. Self-Loading Peristaltic Pumps
Referring toFIG. 24, peristaltic pumps1301-1305 are provided ondeck1200 and are used to drive fluids through photopheresis kit1000 (FIG. 1) along desired pathways. The activation, deactivation, timing, speed, coordination, and all other functions of peristaltic pumps1301-1305 are controlled bysystem controller1210. Peristaltic pumps1301-1305 are identical in structure. However, the placement of each peristaltic pump1301-1305 ondeck1200 dictates the function of each peristaltic pump1301-1305 with respect to which fluid is being driven and along which pathway. This is because the placement of peristaltic pumps1301-1305 dictates which pump loop1220-1224 will be loaded therein.
Referring now toFIGS. 28 and 29,whole blood pump1301 is illustrated in detail. The structure and functioning of whole blood pump will be described with the understanding that peristaltic pumps1302-1305 are identical.Whole blood pump1301 hasmotor1310,position sensor1311,pneumatic cylinder1312,pneumatic actuator1313, rotor1314 (best illustrated inFIG. 30), andhousing1315.
Rotor1314 is rotatably mounted withinhousing1315 and is in operable connection withdrive shaft1316 ofmotor1310. Specifically,rotor1314 is mounted withincurved wall1317 ofhousing1315 so as to be rotatable bymotor1310 about axis A-A. Whenrotor1314 is mounted inhousing1315, aspace1318 exists betweenrotor1314 andcurved wall1317. Thisspace1318 is the tube pumping region ofwhole blood pump1301 into which pump loop tube1121 (FIG. 33) fits when loaded for pumping.Position sensor1316 is coupled to driveshaft1316 ofmotor1310 so that the rotational position ofrotor1314 can be monitored by monitoringdrive shaft1316.Position sensor1311 is operably connected and transmits data to system controller1210 (FIG. 24). By analyzing this data,system controller1210, which is also coupled tomotor1310, can activatemotor1310 to placerotor1314 in any desired rotational position.
Housing1315 also includes ahousing flange1319.Housing flange1319 is used to securewhole blood pump1310 to plate1202 of deck1200 (FIG. 22). More specifically, a bolt is extended throughbolt holes1320 ofhousing flange1319 to threadily engage holes withinplate1202.Housing flange1319 also includes a hole (not shown) to allowpneumatic actuator1313 to extend therethrough. This hole is sized so thatpneumatic actuator1313 can move between a raised and lowered position without considerable resistance.Pneumatic actuator1313 is activated and deactivated bypneumatic cylinder1312 in a piston-like manner through the use of air.Pneumatic cylinder1312 comprisesair inlet hole1321 for connecting an air supply line. When air is supplied topneumatic cylinder1312, pneumatic actuator extends upward throughhousing flange1319 to a raised position. When air ceases to be supplied topneumatic cylinder1312, pneumatic actuator retracts back intopneumatic cylinder1312, returning to the lowered position. System controller1210 (FIG. 22) controls the supply of air to airinlet hole1321.
Curved wall1317 ofhousing1315 contains two slots1322 (only one visible).Slots1322 are located on substantially opposing sides ofcurved wall1317.Slots1322 are provided for allowing pump loop tube1121 (FIG. 33) to pass intotube pumping region1318. More specifically, pumpinlet portion1150 and outlet portions1151 (FIG. 33) ofpump loop tube1121 pass throughslots1322.
Turning now toFIGS. 30 and 31,rotor1314 is illustrated as removed fromhousing1315 so that its components are more clearly visible.Rotor1314 has atop surface1323, angledguide1324,rotor flange1325, twoguide rollers1326, twodrive rollers1327, androtor floor1328.Guide rollers1326 and driverollers1327 are rotatably secured aboutcores1330 betweenrotor floor1328 and abottom surface1329 ofrotor flange1325. As is best illustrated inFIG. 29,cores1330 fit intoholes1331 ofrotor floor1328 andrecesses1332 inbottom surface1329.Guide rollers1326 and driverollers1327 fit aroundcores1330 and can rotate thereabout. Preferably, twoguide rollers1326 and twodrive rollers1327 are provided. More preferably, guiderollers1326 and driverollers1327 are provided onrotor1314 so as to be in an alternating pattern.
Referring toFIGS. 29 and 31,drive rollers1327 are provided to compress the portion ofpump loop tube1121 that is loaded intotube pumping region1318 against the inside ofcurved wall1317 asrotor1314 rotates about axis A-A, thereby deforming the tube and forcing fluids to flow through the tube. Changing the rotational speed ofrotor1314 will correspondingly change the rate of fluid flow through the tube.Guide rollers1326 are provided to keep the portion ofpump loop tube1121 that is loaded intotube pumping region1318 properly aligned during pumping. Additionally, guiderollers1326 help to properly loadpump tube loop1121 intotube pumping region1318. Whileguide rollers1326 are illustrated as having a uniform cross-section, it is preferred that the top plate of the guide rollers be tapered so as to come to a sharper edge near its outer diameter. Tapering the top plate results in a guide roller with a non-symmetric cross-sectional profile. The tapered embodiment helps ensure proper loading of the tubing into the tube pumping region.
Rotor1314 further includescavity1328 extending through its center.Cavity1328 is designed to connectrotor1314 to driveshaft1316 ofmotor1310.
Referring now toFIGS. 30 and 32, rotor flange hasopening1333.Opening1333 is defined by aleading edge1334 and atrailing edge1335. The terms leading and trailing are used assuming thatrotating rotor1314 in the clockwise direction is the forward direction while rotatingrotor1314 in a counterclockwise direction is the rearward direction. However, the invention is not so limited and can be modified for counterclockwise pumps. Leadingedge1334 is beveled downward intoopening1333. Trailingedge1335 extends upward from the top surface ofrotor flange1325 higher than theleading edge1334. Leading edge is provide for trailing edge for capturing and feedingpump loop tube1121 intotube pumping region1318 uponrotor1314 being rotated in the forward direction.
Rotor1314 also has angledguide1324 extending upward, at an inverted angle, fromrotor flange1325.Angled guide1324 is provided for displacingpump loop tube1121 towardrotor flange1325 uponrotor1314 being rotated in the forward direction. Preferably,angled guide1324 has elevatedridge1336 running alongtop surface1323 for manual engagement by an operator if necessary. More preferably, angledguide1314 is located forward of leadingedge1334.
Referring now toFIGS. 28 and 33,whole blood pump1301 can automatically load and unloadpump lop tube1121 into and out oftube pumping region1318. Usingposition sensor1311,rotor1314 is rotated to a loading position whereangled guide1324 will facecassette1100 whencassette1100 is loaded onto deck1200 (FIG. 25). More specifically,rotor1314 is preset in a position so thatangled guide1324 is located betweeninlet portion1150 andoutlet portion1151 ofpump loop1121 whencassette1100 is secured to the deck, as is illustrated inFIG. 13. Whencassette1100 is secured todeck1200, pumplop tube1121 extends over and aroundrotor1314.Pneumatic actuator1313 is in the lowered position at this time.
Oncecassette1100 is properly secured and the system is ready,rotor1314 is rotated in the clockwise direction (i.e., the forward direction). Asrotor1314 rotates, pumptube loop1121 is contacted byangled guide1324 and displaces against the top surface ofrotor flange1325. The portions ofpump loop tube1121 that are displaced againstrotor flange1325 are then contacted by trailingedge1325 and fed downward intotube pumping region1318 throughopening1333. Aguide roller1326 is provided directly after opening1333 to further properly position the tubing within tube pumping chamber for pumping bydrive rollers1327. When loaded,inlet portion1150 andoutlet portion1151 ofpump loop tube1121 pass throughslots1322 ofcurved wall1317. One and a half revolutions are needed to fully load the tubing.
To automatically unloadpump tube loop1121 fromwhole blood pump1301 after the therapy is complete,rotor1314 is rotated to a position whereopening1333 is aligned with theslot1322 through whichoutlet portion1151 passes. Once aligned,pneumatic actuator1313 is activated and extended to the raised position, contacting and liftingoutlet portion1151 to a height above trailingedge1335.Rotor1314 is then rotated in the counterclockwise direction, causing trailing edge to1335 to contact and removepump loop tube1121 fromtube pumping region1318 viaopening1333.
D. Infra-Red Communication
Referring toFIG. 34, tower system2000 (FIG. 17) preferably further includes a wireless infrared (“IR”) communication interface (not shown). The wireless IR interface consists of three primary elements,system controller1210, IRDA protocol integrated circuit,1381, andIRDA transceiver port1382. The IR communication interface is capable of both transmitting and receiving data via IR signals from a remote computer or other device having IR capabilities. In sending data,system controller1210 sends serial communication data to theIRDA protocol chip1381 to buff the data.IRDA protocol chip1381 adds additional data and other communication information to the transmit string and then sends it toIRDA transceiver1382.Transceiver1382 converts the electrical transmit data into encoded light pulses and transmits them to a remote device via a photo transmitter.
In receiving data, IR data pulses are received by a photo detector located on thetransceiver chip1382. Thetransceiver chip1382 converts the optical light pulses to electrical data and sends the data stream toIRDA protocol chip1381 where the electrical signal is stripped of control and additional IRDA protocol content. The remaining data is then sent to thesystem controller1210 where the data stream is parsed per the communication protocol.
By incorporating an IR communication interface ontower system2000 real time data relating to a therapy session can be transmitted to a remote device for recording, analysis, or further transmission. Data can be sent via IR signals totower system2000 to control the therapy or allow protocols to be changed in a blinded state. Additionally, IR signals do not interfere with other hospital equipment, like other wireless transmission methods, such as radio frequency.
III. Photopheresis Treatment Process
Referring together toFIG. 26, a flow chart illustrating an embodiment of the invention which includes photactivation of buffy coat, andFIG. 27, a schematic representation of apparatus which can be employed in such an embodiment, the process starts1400 with apatient600 connected by means of aneedle adapter1193 carrying a needle, for drawing blood, andneedle adapter1194 carrying another needle, for returning treated blood and other fragments.Saline bag55 is connected byconnector1190 andanticoagulant bag54 is connected byconnector1191. Actuators1240,1241, and1242 are opened,anticoagulant pump1304 is turned on, andsaline actuator1246 is opened so that the entire disposable tubing set is primed1401 withsaline55 andanticoagulant54. Thecentrifuge10 is turned on1402, and blood-anticoagulant mixture is pumped1403 to thecentrifuge bowl10, with the A/C pump1304 andWB pump1301 controlled at a 1:10 speed ratio.
When the collected volume reaches150ml1404, thereturn pump1302 is set1405 at thecollection pump1301 speed until red cells are detected1406 at an HCT sensor (not shown) in the centrifuge chamber1201 (FIG. 19). Packed red cells and buffy coat have at this point accumulated in the spinning centrifuge bowl and are pumped out slowly at a rate, controlled by the processor, which maintains the red cell line at the sensor interface level.
Thered cell pump1305 is then set1407 at 35% of the inlet pump speed while controlling1408 the rate to maintain the cell line at the interface level until the collection cycle volume is reached1409, at which point thered cell pump1305 is turned off1410 and the fluid path to thetreatment bag50 via theHCT sensor1125 is opened by loweringactuator1244, and stops when theHCT sensor1125 detects1411 red cells. “Collection cycle volume” is defined as the whole blood processed target divided by the number of collection cycles, for example a white blood process target of 1500 ml may require 6 cycles, and so 1500/6 is a volume of 250 ml. With whole blood continuing at1410 to be delivered from the patient to the bowl and the red cell pump off, red cells will accumulate and will push out the buffy coat from inside thebowl10. The red cells are used to push out the buffy coat and will be detected by the effluent hematocrit (HCT) sensor, indicating that the buffy coat has been collected.
If another cycle is needed1412, thecentrifuge10 effluent path is returned1413 to theplasma bag51 and thered cell pump1305 rate is increased1413 to theinlet pump1301 pump rate until red cells are detected1414, which is the beginning of the second cycle. If anothercycle1412 is not needed, thecentrifuge10 is turned off1415 andinlet pump1301 andanticoagulant pump1304 are set at KVO rate, 10 ml/hr in this embodiment. The effluent path is directed1416 to theplasma bag51, thered cell pump1305 rate is set1417 at 75 ml/min, therecirculation pump1303 and photoactivation lamps are turned on1418 for sufficient period to treat the buffy coat, calculated by the controller depending on the volume and type of disease being treated.
When thebowl10 is empty1419, thered cell pump1305 is turned off1420 and theplasma bag51 is emptied1421 by openingactuator1247 and continuingreturn pump1302. Thereturn pump1302 is turned off1422 when theplasma bag51 is empty and when photoactivation is complete1423, the treated cells are returned1424 to the patient from theplate700 by means of thereturn pump1302. Saline is used to rinse the system and the rinse is returned to the patient, completing theprocess1425.
The anticoagulant, blood from patient, and fluid back to patient are all monitored byair detectors1204 and1202, and the fluid back to the patient goes through drip chamber andfilter1500. The pumps,1304,1301,1302,1303, and1305, theactuators1240,1241,1242,1243,1244,1245,1246, and1247, and the spinning of thebowl10 are all controlled by the programmed processor in the tower.
The process and related apparatus have significant advantages over prior processes and apparatus in that the invention allow buffy coat to be in the bowl longer since red cells are being drawn off while collecting buffy coat in the bowl while centrifuging, keeping more buffy coat in the bowl until the desired amount of buffy coat cells are collected prior to withdrawing the collected buffy cells. Platelets, leukocytes, and other buffy coat fractions can also be separated, or red cells can be collected rather than returning them with plasma to the patient as the illustrated process does.
It has been found that increasing the time that buffycoat810 is subjected to rotational motion incentrifuge bowl10 yields a “cleaner cut” ofbuffy coat820. A “cleaner cut” means that the hematocrit count (HCT %) is decreased. HCT % is the amount of red blood cells present per volume of buffy coat. The amount of time that buffycoat820 is subjected to rotational motion incentrifuge bowl10 can be maximized in the following manner. First,whole blood800 is fed into first bowl channel420 ascentrifuge bowl10 is rotating. As discussed above,whole blood800 is separated intobuffy coat820 and RBC's810 as it moves outwardly atop lower plate300. Second bowl channel410 andthird bowl channel740 are closed at this time. The inflow ofwhole blood800 is continued until the separation volume220 is filled with a combination ofbuffy coat820 near the top and RBC's810 near the bottom ofcentrifuge bowl10. By removing RBC's810 fromcentrifuge bowl10 via second bowl channel410 only, additional volume is created for the inflow ofwhole blood800 and the unremovedbuffy coat820 is subjected to rotational forces for an extended period of time. Ascentrifuge bowl10 continues to rotate, some of the RBC's810 that may be trapped inbuffy coat820 get pulled to the bottom ofcentrifuge bowl10 and away fromthird bowl channel740 andbuffy coat820. Thus, whenthird bowl channel740 is opened, thebuffy coat820 that is removed has a lower HCT %. By controlling the inflow rate ofwhole blood800 and the outflow rates ofbuffy coat820 and RBC's810, a steady state can be reached that yields abuffy coat820 with an approximately constant HCT %.
The elimination of batch processing and the improved yields achieved by the current invention, have reduced the treatment time necessary to properly treat patients. For an average sized adult, 90-100 milliliters of buffy coat/white blood cells must be captured in order to conduct a full photopheresis treatment. In order to collect this amount of buffy coat/white blood cells, the present invention needs to process around 1.5 liters of whole blood. The required amount of buffy coat/white blood cells can be removed from the 1.5 liters of whole blood in about 30-45 minutes using the present invention, collecting around 60% or more of the total amount of the buffy coat/white blood cells that are subjected to the separation process. The captured buffy coat/white blood cells have an HCT of 2% or less. In comparison, one existing apparatus, the UVAR XTS, takes around 90 minutes to process 1.5 liters of whole blood to obtain the sufficient amount of buffy coat/white blood cells. The UVAR XTS only collects around 50% of the total amount of the buffy coat/white blood cells that are subjected to the separation process. The HCT of the buffy coat/white blood cells collected by the UVAR XTS is around, but not substantially below, 2%. Another existing apparatus, the Cobe Spectra by Gambro, must process 10 liters of whole blood in order to collect the sufficient amount of buffy coat/white blood cells. This typically takes around 150 minutes, collecting only 10-15% of the total amount of the buffy coat/white blood cells that are subjected to the separation process, and having an HCT of about 2%. Thus, it has been discovered that while existing apparatus and systems require anywhere from 152 to 225 minutes to separate, process, treat, and reinfuse the requisite amount of white blood cells or buffy coat, the present invention can perform the same functions in less than 70 minutes. These times do not include the patient preparation or prime time. The times indicate only the total time that the patient is connected to the system.