Filtration System for Preparation of Fluids for Medical Applications
A treatment system for performing a treatment on a patient may include a treatment fluid preparation device having a pump connected by a fluid channel to a reservoir of a source fluid, the pump conveying the source fluid from the reservoir, through a filter, and combining the source fluid with a concentrate by pumping the source fluid with the concentrate to form a treatment fluid in a batch container. The treatment fluid preparation device may have a controller that controls a heater, the pump, and a memory. The controller starts the heater to warm the treatment fluid in the batch container at a time that is responsive to the treatment time stored in the memory. The controller also detects a pressure property of the filter to determine its integrity and outputs an indication of a failed batch if the pressure property indicates the integrity of the filter is insufficient.
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The present application is continuation of U.S. application Ser. No. 16/164,047, filed Oct. 18, 2018, which is a continuation of U.S. application Ser. No. 15/195,801 filed Jun. 28, 2016, which is a continuation of U.S. application Ser. No. 13/968,430 filed Aug. 16, 2013, now U.S. Pat. No. 9,388,059 granted Jul. 12, 2016, which is a divisional of U.S. application Ser. No. 13/603,505, filed Sep. 5, 2012, now U.S. Pat. No. 8,545,428 granted Oct. 1, 2013, which is a divisional of U.S. application Ser. No. 13/083,915, filed Apr. 11, 2011, now U.S. Pat. No. 8,679,348, granted Mar. 25, 2014, which is a continuation of U.S. application Ser. No. 10/585,675, filed Jul. 7, 2006 (§ 371(c) date of May 19, 2008), abandoned, which is a national stage entry of International Application No. PCT/US2005/00381, filed Jan. 7, 2005, which is a continuation of International Application No. PCT/US2004/00476, filed Jan. 7, 2004, which claims benefit to U.S. Provisional Application No. 60/438,567, filed Jan. 7, 2003, all of which are incorporated herein by reference in their entireties.
BACKGROUND OF THE INVENTIONMany medical applications require purified water and other fluids, for example, hemofiltration, tissue irrigation, and hemodiafiltration. Some prior art systems have focused on continuous purification processes that require a separate filtration/purification apparatus that must be periodically purged and verified to provide sufficient constant flow of sterile replacement fluid. (See Chavallet U.S. Pat. Nos. 6,039,877 and 5,702,597.) Such devices are necessarily complicated and require separate pumping systems for the purification process. In addition, the rate of supply of fluid for such systems is very high, requiring expensive filters to be used. The same high-rate problem exists for the generation of replacement fluid for hemofiltration, and therefore also requires expensive filtering apparatus.
Large and small scale inline systems are known for preparation of infusible fluids and for preparation of dialysate. The following prior art references discuss examples of such systems.
- U.S. Patent Publication No. 2004/0232079
- U.S. Patent Publication No. 2003/0105435
- U.S. Pat. No. 5,645,734
- U.S. Pat. No. 5,782,762
- U.S. Pat. No. 6,136,201
- PURELAB Maxima, Ultra-Pure Water Purification Systems
- Shipe, Brad; “The Case for UV in Dechlorination Applications,” Water Conditioning & Purification Magazine, January 2003, Vol. 45, No. 1
The present disclosure relates to apparatus, methods, devices, articles of manufacture, etc. for producing pure water and, in some embodiments, pure solutions. These may be used for the preparation of solutions for medical applications such as tissue irrigation, preparation of pharmaceutical, blood treatments such as hemofiltration, hemodialysis, hemodiafiltration and ultrafiltration, and other treatments.
As described in
Between the first and second filter stages 410A and 410B, a water quality sensor 405 is provided. In an embodiment, the water quality sensor 405 is a conductivity or resistivity probe that detects ionic species in the water after passing through the first stage filter 410A. In a preferred embodiment, the second stage 410B provides at least some redundancy in that the second stage 410B provides some of the filtration effect of the first stage 410A. In an alternative embodiment it provides all of the filtration of the first stage 410A and is thereby completely redundant. In such an arrangement, the first stage would expire (become depleted), allowing contaminants to break through, before the second stage expires. The contaminant breakthrough is detected by a controller 415 connected to the water quality sensor 405. The controller 415 also controls the pump 416. Upon expiration of the first stage 410A, the controller allows the preparation to continue until a certain amount of fluid is collected in batch container 417, preferably an amount required for a treatment. Once this threshold quantity is delivered, the controller will not allow the pump 416 to be started until the filter module 425 is exchanged with a fresh one. The second stage filter 410B, preferably, is sized to ensure that, by itself, it can purify at least a single batch of water, plus a safety margin without any contaminant breakthrough to the output line 404. In a preferred embodiment, the second stage filter 410B is a smaller size than the first 410A. In the preferred embodiment, the second stage filter 410B may be of a different type which may not be as able to handle high contamination loads as the first 410A. This may be acceptable because, although after breakthrough is detected, the emerging fluid is still substantially purified and the load input to the second stage filter 410B may remain low until a single batch of fluid is prepared.
In an alternative embodiment, the filter module 425 is provided with a permanently attached data carrier 423 such as radio frequency identification device (RFID), bar code (1- or 2-dimensional), contact-type identification device, etc. The data carrier 423 contains a unique identifier of the filter module. When a cartridge is connected to the pump, the controller 415 reads the data carrier 423 using a reader device 422 and stores the identifier in a memory 437. If the water quality sensor 405 indicates contaminant breakthrough, the controller permanently stores the identifier in an expired directory in the memory, which has a non-volatile portion for the directory. If a user attempts to connect a module 425 with an identifier stored in the directory, the controller will not operate the pump and will indicate the error condition by means of an annunciator 420 or equivalent device, such as an LCD display message.
Note that in an alternative device, the data carrier 423 is a programmable device with a writable memory. In this embodiment, the controller 415 programs the data carrier 423 with a flag indicating that the filter module 425 is expired. The controller 415 then prevents the initiation of a new batch.
Referring to
The special clamping connector 442 may any suitable device that seals off, to prevent contamination. An embodiment of such a connector is shown in
Returning to
Referring to
Referring to
Note that pressure indicators 1015 and 1025 may be pressure transducers that feed control signals to a control device such as discussed with reference to
Referring to
Note that instead of using layered beds in a single cartridge as described, separate cartridges each containing one of a SBA and SAC filter bed may be used. Also, each cartridge could contain more than one layer of each to provide similar results.
The resistivity probe 1022 detects ion concentration by contact testing of the resistivity of the water. A signal is generated to indicate that this will be the last allowed batch before the system will require the replacement of the replaceable module 910. Control may be provided as in the embodiment of
Note, it should be clear that resistivity probe 1022 may be used in a configuration such as that of
Note that two separately-housed ultrafilters 1035A and 1035B are serially interconnected. The separate housings ensure against failure mechanisms such as grow-through of pathogens, adjacent simultaneous or shared seal failure. For example, prior art reference U.S. Patent Publication No. 2003/0105435, cited in the Background section, shows a filter cartridge with two microporous membranes in adjacent layers of a filter cartridge housing. These may share a seal mechanism or adjacent seals such that failure of the seal of one necessarily involves failure of the seal of the other. Also once a grow through problem occurs in one, the adjacency may cause the problem to creep directly into the adjacent membrane. These problems are prevented by the illustrated arrangement of separate redundant ultrafilters.
Note that the benefit of separately housed filters may be substantially provided in a single housing by substantially separating two ultrafilter layers. Referring to
Note the final conductivity/resistivity sensor/alarm 1025 may control the pump, as noted. A controller 1090 may be connectable to the disposable filter module 910 and configured to stop the pump 1020. The trigger resistivity safety level to cut-off the pump 1020 may be 1 megohm, but may be raised to 2 megohm to allow the use of required temperature compensated resistivity probes (an FDA & AAMI requirement) This does allow use of low cost in-line resistivity probes in the disposable filter module 910.
Preferably, the filter module 910 as well as the modules of other embodiments are of such a flow rate that upward flow of fluids is possible. Generally, prior art deionization beds suffer from the problem of floating or loosening resin particles which may have been disturbed during handling. The separation and floating of the particles breaks up the beds and renders the filters less effective. To avoid this, generally, filter systems are configured to direct flow downwardly through the beds to help keep and compress the resin particles. But if flow rates are kept low, as may be done in the present system, water may be flowed in an upward direction which helps to eliminate air from stream. Air is a notorious problem in the preparation of medicaments such as dialysate. The precise flow rates needed to allow upward flow will vary according to the characteristics of the system. One way to allow faster flow rates without being hampered by break away resin particles is to provide a bed compressor of resilient porous material to compress the bed. Referring momentarily to
The following is an example procedure for using the devices discussed with reference to
1. Remove the dialysate concentrate tubing set 915 and remove the cap 14 from the tubing line 7 that contains the filter 11. (The 0.22 micron filter 11 provides additional protection from inadvertent contamination.)
2. Connect the outlet line 404 to the concentrate bag luer connection 9.
3. Break the frangible luer connector 4 which connector is configured to form a permanent seal on the side facing the Y-junction 5 when disconnected.
4. Add predetermined quantity of water into the concentrate bag using the purification plant through tubing branch 7 through luer connector 9.
5. Optionally a user can write on the bag label the date and time water was first added to the concentrate bag, to assist in ensuring that it is used within a period of time. An automated scheme may be employed as well.
6. Shake the batch container 1 well to mix.
7. Confirm solution conductivity prior to use. Remove the break-off cap 1 and draw sample from this branch 15. After removing the sample, clamp the line using the pinch clamp 17 provided.
8. (The following is normative according to a preferred embodiment and not limiting of the invention) Conductivity must be in the range 13.0 to 14.4 mS/cm. Nominal conductivity for the dialysate solution is 13.7 mS/cm at 25° C. If conductivity does not meet this specification do not use it. Verify that the results are accurate. If conductivity is high additional water may be added to bring it within specification. If conductivity is low then the solution must be discarded.
9. Using the non re-opening clamp 13 provided, clamp the line that is connected to the water purification plant.
10. The clamp 6 is, next, clamped on the line that is connected to the dialysate bag 1.
11. Disconnect the water source at the luer connection 26.
12. Connect the bag of dialysate solution to the dialysis circuit at the connection 8. This leaves the filter 11 and permanent clamp 13 in place to protect the water supply source.
13. Unclamp the line going to the dialysate bag using clamp 6, and initiate treatment after verifying that dialysate will be used within 24 hours from when water was added.
Referring to
At 110, a fitting connecting a sample or feed line 145 is shown. The latter may be used, with a connector 156, connect a sampling syringe to draw out a sample of a medicament or infusate. A check valve may be provided at 155 to prevent ingress of contaminants. A clamp (not shown separately) may be provided as well to guard against contamination. In an alternative embodiment, line 145 may be configured for injecting a soluble concentrate into the batch container 100 before the container 100 is sealed and sterilized as a unit (for example, by gamma ray sterilization). When a prescribed quantity of purified water is added to the batch container, the diluted concentrate may form a medicament or infusate such as replacement fluid for hemofiltration or a dialysate for hemodialysis. Line 145 may also represent a draw line that may be connected to a treatment machine. In the latter case, a sterile filter (at 155), such as a microporous membrane of 0.2μ may be provided to guard against touch contamination. Additionally, a clamp may be provided as at 155.
In the embodiment of
Referring to
Referring to
A data carrier may include software and instructions for using the filter module 1125. These may be read by a permanent component of a filtering system as described in connection with
In an embodiment, features indicated at 301-306 may be added to allow the base unit 335 to control when and whether an outlet line of a batch container should be opened and clamped. A batch container is fitted in the station 305 and an outlet line of the batch container fitted between clamping portions 303 and 304. A detector 306 verifies that the line has been fitted in place. When the system is run, an actuator 302 and motor 301 may be activated to clamp the line during fluid purification and as the batch container is filled. After the batch is filled, the clamp may remain closed until a treatment operation, which may be run while the batch container remains in place, is begun. At treatment time, the clamp mechanism 303 and 304 can enforce the expiration time of the batch of fluid. For example, a timer can be started within the controller of the base unit or, equivalently, a time/date stamp stored and the clamp only released if the batch of fluid is used for treatment within a certain period of time. For this purpose a treatment machine and the base unit 335 may be combined into a single device under common control or the two may be linked by a data link to operate cooperatively to achieve such a result. The flow chart of
Referring now to
Referring to
A sample program for operating the various embodiments described herein is shown in
At step S55 depending on the type of data carrier (e.g., programmable or just carrying a unique ID), the expired or spent unit is indicated as expired so that reuse can be prevented. For example, in S55 the data carrier may be programmed with a token to indicate that the attached filter module is expired or a server may be sent a message to indicate that its unique ID should be added to a list of expired IDs. Any suitable device may be used to “expire” a unit. Since expiring a unit may still allow a batch to be prepared, control returns to S40. Completion of the treatment may be determined at step S45 by measuring the total mass pumped or by other means. For example, if the embodiment provides a conductivity probe in the batch container, step S45 may depend on the measured conductivity of the batch contents. Once completion is determined, the system may be halted at step S50 and the batch bag “stamped” with a time and date. Note that further instructions may be output at this point.
In one embodiment, the water purification and treatment may be done from a single apparatus and under common control. The steps following step S50 illustrate this. Assuming purified fluid has been added to a batch container of some description such as those described in the current specification or some other, the contents of the container may be mixed, if a solute is involved, and the contents checked in some way in step S51. For example, the conductivity of a mixed batch or the resistivity of a pure batch can be checked determine its conformity with treatment specifications. In step S52, if a value is out of range, control passes to step S30, but if not, the batch may be utilized at any time up to an expiration time/date (MTU time, or Mixed Till Use-time). In step S53, an outlet clamp that prevents fluid from being drawn from the batch container is released to allow a treatment to be performed with the fluid product. At the same time, an acceptance message can be output to the user on a display. At this time, in S54, a time stamp is stored or a timer started to keep track of the expiration of the batch of fluid. If the expiration is not observed, which is tested at step S56 by checking to see if the timer has expired, the clamp will close in step S30 (under the general step indicated as “take action”) and an appropriate message output. The system will then wait until treatment is completed while, optionally, continuously checking the MTU timer in steps S46 and S56.
Note that many of the described mechanical and control features are novel and inventive alone, as subcombinations with other features and their description in combination in the above embodiments is not intended to be interpreted as limiting of the inventions disclosed herein. Referring to
Referring to
An alternative design that integrates air vent configurations into the housing of the ultrafilter 714 is shown in
Referring to
One of the drivers for the features discussed above is a need to provide pure water irrespective of input water quality. The above embodiments are not reliant upon water quality and are designed to reliably produce pure water or solutions regardless of input water quality. Various embodiments are also designed to reduce the costs associated with lower volume (10-60 liters) preparation of medical and other pure solutions and to maintain simplicity through the combination of semi-permanent and single-use modules which combine to eliminate the complexities, costs and safety issues associated with maintenance, sterilization, and operation of many other prior art systems.
Although the foregoing inventions have, for the purposes of clarity and understanding, been described in some detail by way of illustration and example, it will be obvious that certain changes and modifications may be practiced that will still fall within the scope of the appended claims. For example, the devices and methods of each embodiment can be combined with or used in any of the other embodiments. For another example, the air vents described can be of any suitable description and need not be membrane type air vents at all, although these are preferred.
Claims
1. A treatment system for performing a treatment on a patient, the treatment system comprising:
- a treatment fluid preparation device connected to a source of fluid;
- the source of fluid including one or more of: a container of sterile or non-sterile replacement fluid, one or more containers of constituents which, when combined, form a replacement fluid, and a continuous source such as a water tap;
- the source of fluid being connected by a line to convey fluid a filter and into a mixing container;
- the source of fluid including a batch container elevated at a predefined height to provide a predefined head pressure;
- the batch container being a disposable container or a number of disposable containers interconnected to permit flow into and out of them;
- the treatment system including a pump to pump a fluid across the filter into the mixing container.
2. The system of claim 1, wherein the pump is regulated responsively to a magnitude of the transmembrane pressure.
3. The system of claim 1, wherein the pump is regulated to limit a transmembrane pressure of the filter.
4. The system of claim 1, further comprising a controller that controls the administration of heat to the mixing container.
5. The system of claim 1, further comprising a treatment component that withdraws a treatment fluid from the mixing container and conveys treatment fluid to and from a patient.
6. A treatment system for performing a treatment on a patient, the treatment system comprising:
- a treatment fluid preparation device connected to a source of fluid;
- the source of fluid including one or more of: a container of sterile or non-sterile replacement fluid, one or more containers of constituents which, when combined, form a replacement fluid, and a continuous source such as a water tap;
- the source of fluid being connected by a line to convey fluid a filter and into a mixing container;
- the batch container being a disposable container or a number of disposable containers interconnected to permit flow into and out of them;
- the treatment system having a controller that controls a pump that regulates the flow of fluid from the source of fluid to the mixing container;
- a treatment component that withdraws a treatment fluid from the mixing container and conveys treatment fluid to and from a patient.
7. The system of claim 6, wherein the pump is regulated responsively to a magnitude of the transmembrane pressure.
8. The system of claim 6, wherein the treatment component has a further controller which further controller controls the pump of the treatment fluid preparation device.
9. A treatment system for performing a treatment on a patient, the treatment system, comprising:
- a treatment fluid preparation device having a pump connected by a fluid channel to a source of fluid;
- the pump and fluid channel being configured convey the source fluid through a filter, to combine water and concentrated fluids effective to form a batch of treatment fluid in a mixing container by pumping them from the source of fluid through the fluid channel;
- the treatment fluid preparation device having a controller with a memory configured to control a heater and the pump;
- the controller being configured to start a treatment when the batch of treatment fluid reaches a target temperature;
- the controller controlling the pump to administer heated treatment fluid from the batch container to a patient at a predefined flow rate and to withdraw waste fluid from the patient.
10. The system of claim 9, wherein the controller is further configured to detect exhaustion of the treatment fluid in the batch container and the controller is further configured to halt the heater upon completion of administration of the treatment fluid.
11. The system of claim 9, wherein the controller is configured to halt the pump after displacement of a predetermined volume of the treatment fluid.
12. The system of claim 9, wherein the controller is configured to detect a pressure property of the filter to determine its integrity and to output an indication of a failed batch responsively to the pressure property indication.
13. The system of claim 17, wherein the pressure property includes a transmembrane pressure.
14. The system of claim 9, wherein the controller is configured to maintain a balance between the treatment fluid administered to the patient and waste fluids withdrawn from the patient.
15. The system of claim 9, wherein the controller is configured to measure a conductivity of the treatment fluid.
16. The system of claim 15, wherein the controller is configured to measure the conductivity of the treatment fluid before the treatment.
17. The system of claim 9, the concentrate is stored in a concentrate container and the concentrate container and the batch container are interconnected by tubing containing a sterile filter.
18. The system of claim 9, wherein the water includes purified water.
19. The system of claim 9, wherein the concentrated fluids are effective to form, when diluted with the water, a dialysate.
20. The system of claim 9, wherein the controller has a user interface connected to the controller, the user interface being configured to receive user input specifying the treatment time.
21. The system of claim 9, where in the source fluid includes a batch container from which source fluid is drawn.
22. A treatment fluid preparation system, comprising:
- a first fluid device connected to a water tap connected by a fluid channel to a filter and in turn to a batch container;
- the first fluid device having a controller that controls a pump in the fluid channel that controls the flow of water through the filter;
- a second fluid device controller controlling a pump of the second fluid device to receive fluid from the batch container.
23. The system of claim 22, wherein the second fluid device is connected to the batch container, the second fluid device having a controller connected by a communications channel which includes a wire harness, separate wires, a bus, a wireless channel, or a communications/power transmission device.
24. The system of claim 23, wherein the second fluid device controller controls the first fluid device pump without sending information to the first fluid device controller.
25. A treatment system for performing a treatment on a patient, the treatment system, comprising:
- a treatment fluid preparation device having a pump connected by a fluid channel to a source of fluid;
- the pump and fluid channel being configured convey the source fluid through a filter, to combine water and concentrated fluids effective to form a batch of treatment fluid in a mixing container by pumping them from the source of fluid through the fluid channel;
- the treatment fluid preparation device having a controller with a memory which is configured to control a heater and the pump;
- the controller being configured to start the heater to warm the treatment fluid in the mixing container at a time that is responsive to the treatment time stored in the memory;
- the controller controlling the pump to administer heated treatment fluid from the batch container to a patient at a predefined flow rate and to withdraw waste fluid from the patient.
26. The system of claim 25, wherein the controller is further configured to detect exhaustion of the treatment fluid in the batch container and the controller is further configured to halt the heater upon completion of administration of the treatment fluid.
27. The system of claim 25, wherein the controller is configured to halt the pump after displacement of a predetermined volume of the treatment fluid.
28. The system of claim 25, wherein the controller is configured to detect a pressure property of the filter to determine its integrity and to output an indication of a failed batch responsively to the pressure property indication.
29. The system of claim 33, wherein the pressure property includes a transmembrane pressure.
30. The system of claim 25, wherein the controller is configured to maintain a balance between the treatment fluid administered to the patient and waste fluids withdrawn from the patient.
31. The system of claim 25, wherein the controller is configured to measure a conductivity of the treatment fluid.
32. The system of claim 25, wherein the controller is configured to measure the conductivity of the treatment fluid before the treatment.
33. The system of claim 25, the concentrate is stored in a concentrate container and the concentrate container and the batch container are interconnected by tubing containing a sterile filter.
34. The system of claim 25, wherein the water includes purified water.
35. The system of claim 25, wherein the concentrated fluids are effective to form, when diluted with the water, a dialysate.
36. The system of claim 25, wherein the controller has a user interface connected to the controller, the user interface being configured to receive user input specifying the treatment time.
37. The system of claim 25, where in the source fluid includes a batch container from which source fluid is drawn.
Type: Application
Filed: Nov 9, 2018
Publication Date: Mar 14, 2019
Applicant: NxStage Medical, Inc. (Lawrence, MA)
Inventors: Jeffrey H. BURBANK (Boxford, MA), Dennis M. TREU (Castle Rock, CO), Christopher S. MCDOWELL (Murray, UT), Goetz FRIEDERICHS (Boston, MA)
Application Number: 16/185,525