Peritoneal dialysis system having modular flat sheet membrane filters - Patents.com

Abstract

The peritoneal dialysis ("PD") system (10) includes a PD machine (20), a patient line (50) extending from the PD machine (20), and a filter set (100) in fluid communication with the patient line (50), the filter set (100) including filter bodies (110, 150, 190) housing first and second filter membranes (112a, 112b, such as sterilizing grade or bacterial reducing filter membranes), the filter bodies (110, 150, 190) being configured to be arranged in different arrangements such that fresh PD fluid either (i) flows through the first filter membrane (112a) and then through the second filter membrane (112b), or (ii) splits and flows in parallel through the first and second filter membranes (112a, 112b).

Description

[Technical field]

[0001] Priority claim This application claims priority to and the benefit of U.S. Provisional Application No. 63 / 291,073, filed December 17, 2021, the entire contents of which are incorporated herein by reference.

[0002] background FIELD OF THE DISCLOSURE The present disclosure relates generally to medical fluid treatment, and more particularly to filtration of treatment fluids during dialysis fluid treatment. [Background technology]

[0003] A variety of causes can cause a person's renal system to fail. Renal failure results in several physiological disturbances: it is no longer possible to balance water and minerals or excrete the daily metabolic load. Toxic end products of metabolism such as urea, creatinine, and uric acid can accumulate in the patient's blood and tissues.

[0004] Reduced kidney function, particularly kidney failure, is treated by dialysis. Dialysis removes waste, toxins and excess water from the body that normally functioning kidneys would otherwise remove. Dialysis treatment for replacement of kidney function is important for many people because the treatment is life-saving.

[0005] One type of renal failure treatment is hemodialysis ("HD"), which generally uses diffusion to remove waste products from a patient's blood. A diffusion gradient occurs across a semi-permeable dialyzer between the blood and an electrolyte solution called the dialysate or dialysis fluid, causing diffusion.

[0006] Hemofiltration ("HF") is an alternative renal replacement therapy that relies on the convective transport of toxins from the patient's blood. HF is accomplished by adding substitution or replacement fluid to the extracorporeal circuit during the procedure. Substitution fluid and fluids accumulated by the patient during the procedure are ultrafiltered over the course of the HF procedure, providing a convective transport mechanism that is particularly beneficial for removing middle and large molecules.

[0007] Hemodiafiltration ("HDF") is a procedure that combines convective and diffusive clearance. HDF uses dialysis fluid flowing through a dialyzer, similar to standard hemodialysis, to provide diffusive clearance. In addition, substitution solution is delivered directly to the extracorporeal circuit to provide convective clearance.

[0008] Most HD, HF, and HDF treatments are performed in centers. There is a trend today toward home hemodialysis ("HHD") because HHD can be performed daily, providing therapeutic benefits over in-center hemodialysis treatments, which are typically performed two or three times a week. Studies have shown that more frequent treatments remove more toxins and waste products and experience less interdialytic fluid overload than patients undergoing less frequent, but perhaps longer, treatments. Patients undergoing more frequent treatments do not experience as many down cycles (fluid and toxin fluctuations) as in-center patients who build up two or three days' worth of toxins before treatment. In certain regions, the nearest dialysis center may be many miles away from the patient's home, causing door-to-door treatment times to consume a large portion of the day. Treatments at a center closer to the patient's home may also consume a large portion of the patient's day. HHD can be performed overnight or during the day while the patient relaxes, works, or is otherwise productive.

[0009] Another type of renal failure treatment is peritoneal dialysis ("PD"), in which dialysis solution, also called dialysis fluid or PD fluid, is infused into a patient's peritoneal cavity via a catheter. The PD fluid contacts the peritoneal membrane in the patient's peritoneal chamber. Waste, toxins and excess water pass from the patient's bloodstream through capillaries in the peritoneal membrane and enter the PD fluid by diffusion and osmosis, i.e., an osmotic gradient occurs across the membrane. An osmotic agent in the PD fluid provides the osmotic gradient. The spent PD fluid is drained from the patient, removing the waste, toxins and excess water from the patient. This cycle may be repeated, for example, multiple times.

[0010] There are various types of peritoneal dialysis therapy, including continuous ambulatory peritoneal dialysis ("CAPD"), automated peritoneal dialysis ("APD"), tidal flow dialysis, and continuous flow peritoneal dialysis ("CFPD"). CAPD is a manual dialysis procedure, in which a patient manually connects an implanted catheter to a drain to allow spent PD fluid to drain from the patient's peritoneal cavity. The patient then switches the fluid communication, connecting the patient catheter to a bag of fresh PD fluid and infusing the patient with fresh PD fluid through the catheter. The patient disconnects the catheter from the fresh PD fluid bag, allowing the PD fluid to remain in the patient's peritoneal cavity, where waste, toxins, and excess water are transported. After a dwell period, the patient repeats the manual dialysis procedure, for example, four times a day. Manual peritoneal dialysis requires a significant amount of time and effort from the patient, leaving ample room for improvement.

[0011] APD is similar to CAPD in that the dialysis treatment includes drain, fill and dwell cycles. However, APD machines perform the cycles automatically, usually while the patient sleeps. APD machines do not require the patient to manually perform the treatment cycles and do not require the patient to have supplemental substances delivered during the day. APD machines fluidly connect to an implanted catheter, a source or bag of fresh PD fluid, and a fluid drain. The APD machine pumps fresh PD fluid from the dialysis fluid source through the catheter and into the patient's peritoneal chamber. APD machines also allow the PD fluid to dwell in the chamber, allowing waste, toxins and excess water to be transferred. The source may contain multiple liters of dialysis fluid, including several solution bags.

[0012] APD machines used a pump to drain PD fluid from the patient's peritoneal cavity through a catheter. As with the manual process, several drain, fill and dwell cycles occur during dialysis. A "last fill" may occur at the end of an APD treatment. The last fill fluid may remain in the patient's peritoneal cavity until the start of the next treatment, or it may be manually emptied at some point during the day.

[0013] PD fluids must be sterile or very close to sterile because they are injected into the patient's peritoneal cavity and are therefore considered drugs. Bagged PD fluids are generally adequately sterilized for the procedure, but PD fluids made on-line or PD machines or cyclers that use disinfection may require additional sterilization.

[0014] Therefore, there is a need for an effective, low-cost method of providing additional sterilization to fresh PD fluid before it is delivered to the patient. Summary of the Invention [Means for solving the problem]

[0015] overview The present disclosure provides a peritoneal dialysis ("PD") system having a PD machine or cycler that pumps fresh PD fluid to a patient through a patient line and removes spent PD fluid from the patient via the patient line. The patient line may be reusable or disposable, and in either case operates with and is in fluid communication with a filter set. If the patient line is reusable, the reusable patient line is connected to the filter set during treatment. If the patient line is disposable, in one embodiment, the filter set is merged with a disposable patient line. In either configuration, the distal end of the filter set can be connected to a patient transfer set that is in fluid communication with the patient's indwelling catheter.

[0016] The PD machine or cycler can include a durable PD fluid pump that pumps the PD fluid through the pump itself without the use of disposable components, or a disposable-type PD fluid pump that includes a pump actuator that actuates a disposable, fluid-contacting pumping component, such as a peristaltic pump tubing or a flexible pumping chamber. The PD machine or cycler also includes a number of valves that can be flow-through and durable as well without operating with disposable components, or disposable-type valves with valve actuators that actuate disposable, fluid-contacting valve components, such as tubing segments or cassette-based valve seats.

[0017] The pump and valves are under the automatic control of a control unit provided by the machine or cycler. In one embodiment, the valves include a fresh PD fluid valve that the control unit opens to allow the PD fluid pump to pump fresh PD fluid to the patient through the fresh PD fluid lumen of the dual lumen patient line. The valves also include a spent PD fluid valve that the control unit opens to allow the PD fluid pump to pump spent PD fluid from the patient through the spent PD fluid lumen of the dual lumen patient line. While a single PD fluid pump can be used, it should be understood that dedicated fresh and spent PD fluid pumps can alternatively be used. Also, a single PD fluid pump can include multiple pumping chambers for a more continuous PD fluid flow.

[0018] The present disclosure describes multiple embodiments of modular filter sets. The modular filter sets can be configured to provide redundant filters, dual membrane filters, and single membrane filters. In one main embodiment, the modular filter sets include filter membrane modules that are configured the same regardless of whether a redundant filter, dual membrane filter, or single membrane filter is provided. The membrane modules operate with different fluid spacers that determine how the fresh PD fluid flows. The fluid spacers may be located, for example, between two common membrane modules and may be ultrasonically sealed, heat sealed, and / or adhesively sealed, for example, via solvent bonding.

[0019] The redundant spacer directs fresh PD fluid entering the spacer through one of the membrane modules, filtered through the filter membrane of that membrane module (first filtration), through a second membrane module, filtered through the filter membrane of the second membrane module (redundant filtration), out of the second membrane module, back to the redundant spacer, and then to the patient via the patient lumen of the redundant spacer. The overall redundant modular filter set is advantageous in that it provides the necessary sterilization even if one of the filter membranes is compromised, leaving the dual filtration of both filter membranes intact.

[0020] Instead, the dual membrane spacer allows fresh PD fluid entering the spacer to flow in two directions, either simultaneously or in parallel, through both membrane modules, split and filtered through both filter membranes, either simultaneously or in parallel, and out both the first and second membrane modules, back into the dual membrane spacer, and then out to the patient via the patient lumen of the redundant spacer. The overall dual membrane modular filter set is advantageous in that it effectively doubles the flow capacity of the filter set.

[0021] A single membrane spacer is used with a single membrane module, where fresh PD fluid entering the spacer flows into the membrane module, is filtered through the filter membrane of the membrane module, flows out of the membrane module back into the single membrane spacer, and then flows to the patient via the patient lumen of the single membrane spacer. The overall single membrane modular filter set is advantageous in terms of reducing size and cost.

[0022] In a second main embodiment, the modular filter set eliminates the spacers. Again, the membrane module is constructed (at least initially) in the same way regardless of whether a redundant filter, a dual membrane filter, or a single membrane filter is provided. Here, the membrane module is formed with the necessary openings (ports) and lumens or passages for each of the redundant, dual membrane and single membrane filter versions. The final manufacturing step is to plug the unused openings (ports) and unnecessary lumens or passages so that the desired overall flow path through the modular filter set is formed.

[0023] The redundant modular filter set of the second main embodiment is plugged such that fresh PD fluid entering one of the membrane modules is filtered through the filter membrane of that membrane module (first filtration), flows to a second membrane module, is filtered through the filter membrane of the second membrane module (redundant filtration), and flows out of the second membrane module to the patient via the patient lumen. The overall redundant modular filter set of the second main embodiment is similarly advantageous as it provides the necessary sterilization even if one of the filter membranes is compromised, and provides dual filtration if both filter membranes are intact.

[0024] Instead, the dual membrane modular filter set of the second main embodiment is plugged such that fresh PD fluid entering one of the membrane modules first flows to a similar compartment of the second membrane module, is filtered through both filter membranes simultaneously or in parallel, flows to the patient lumen of one of the membrane modules, and then flows to the patient via the patient lumen. The overall dual membrane modular filter set of the second main embodiment is similarly advantageous by effectively doubling the flow capacity of the filter set.

[0025] The single membrane modular filter set of the second main embodiment uses a single membrane module, where the single membrane module is plugged such that fresh PD fluid entering the membrane module flows into the inlet compartment, is filtered through the filter membrane of the membrane module into the outlet compartment, and flows out of the outlet compartment to the patient via a patient lumen in the outlet compartment. The overall single membrane modular filter set of the second main embodiment is similarly advantageous in terms of reduced size and cost.

[0026] In the third main embodiment, the modular filter set also eliminates spacers and stacks the membrane modules. An inlet cover and an outlet cover are also provided. The inlet cover includes a fresh PD fluid inlet. The outlet cover includes a patient lumen that carries the filtered fresh PD fluid to the patient and removes the spent PD fluid from the patient. After the desired number of membrane modules are stacked together (which may be only a single module or two or more modules), the inlet cover and outlet cover are mated to the exposed surfaces of one or more membrane modules, and the modules and covers are ultrasonically sealed, heat sealed, and / or adhesively sealed, for example via solvent bonding, to form the modular filter set of the third main embodiment.

[0027] The redundant modular filter set of the third main embodiment is configured such that fresh PD fluid entering one of the membrane modules of the stack through the inlet cover is filtered through the filter membrane of that membrane module (first filtration), flows to a second membrane module of the stack, is filtered through the filter membrane of the second membrane module (redundant filtration), and flows out of the second membrane module to the patient through the patient lumen of the outlet cover. The overall redundant modular filter set of the third main embodiment is similarly advantageous as it mitigates a compromised filter membrane and provides dual filtration if both filter membranes are intact.

[0028] Instead, the dual membrane modular filter set of the third main embodiment is configured such that fresh PD fluid entering through the inlet cover flows in parallel through both membrane modules, is filtered through both filter membranes simultaneously or in parallel, flows to the patient lumen of the outlet cover, and then flows to the patient via the patient lumen. The overall dual membrane modular filter set of the third main embodiment also preferably doubles the flow capacity of the filter set.

[0029] The single membrane modular filter set of the third main embodiment uses a single membrane module in combination with an inlet cover and an outlet cover that are sealed to the single membrane module such that fresh PD fluid entering the membrane module through the inlet cover flows into the inlet compartment of the membrane module, is filtered through the filter membrane of the membrane module into the outlet compartment of the membrane module, and flows out of the outlet compartment to the patient via the patient lumen of the outlet cover. The overall single membrane modular filter set of the second main embodiment similarly reduces size and cost.

[0030] The membrane module of the third main embodiment can include different frames that are selected and stacked together to form a redundant, dual membrane modular filter set. One of the frames pushes all incoming fresh PD fluid to be filtered through the filter membrane fixed to the frame (used for the redundant, single membrane modular filter set). The other frame allows the incoming fresh PD fluid to be split between (i) being filtered through the filter membrane fixed to the frame and (ii) bypassing the filter membrane and flowing through an opening to another membrane module (used for the dual membrane modular filter set).

[0031] As previously mentioned, the fresh and spent PD fluid lumens of the dual lumen patient line may be reusable or disposable. If the fresh and spent PD fluid lumens are reusable, they terminate in a patient line connector that connects to the respective lumen connectors of the modular filter set described herein. The lumen connector in one embodiment includes a fresh PD fluid port for communicating with the fresh PD fluid lumen of the dual lumen patient line and a spent PD fluid port for communicating with the spent PD fluid lumen of the dual lumen patient line. The lumen connector may also include threads for mating with threads of the patient line connector. Threading of the patient line connector into the lumen connector seals the mating port of the patient line connector against the fresh and spent PD fluid ports of the lumen connector, in one embodiment, via, for example, one or more gaskets.

[0032] Each of the modular filter sets described herein may also include a transferset connector that connects to a short flexible tube disposed between the body of the filter set and the patient's transferset, such that the generally rigid modular filter set is spaced from the generally rigid transferset to aid in patient comfort. That is, the directly abutting bodies of the filter set and transferset may result in a combined rigid structure that is uncomfortable for the patient while sleeping. The transferset connector may simply be a tube port for sealingly receiving a short flexible tube, or it may be a threaded connector that screws into a mating connector on the end of the short flexible tube.

[0033] For any of the modular filter sets described herein, the spent PD fluid drawn through the patient's transfer set flows under negative pressure through a short flexible tube, and through the transfer set connector, patient lumen, and spent PD fluid port of the lumen connector of the modular filter set via a PD fluid pump. The spent PD fluid is drawn back from the modular filter set through the spent PD fluid lumen of the dual lumen patient line to the PD machine or cycler. The PD machine or cycler pumps the spent PD fluid under positive pressure and drains it. The spent PD fluid of each of the modular filter sets discussed herein generally does not contact the underside of the filter membrane. Contact of the effluent is minimal so that the filter membrane of the present disclosure remains viable over the course of multiple fills of processing before being discarded with the filter set.

[0034] The hydrophilic nature of the filter membranes used in any of the modular filter sets discussed herein prevents air from migrating across the membranes once the membranes are fully wetted with fresh PD fluid, thus serving the secondary end-stage air removal purpose. However, if desired, it is contemplated to provide one or more hydrophobic membranes upstream of the most upstream filter membrane (from the perspective of fresh PD fluid), e.g., adjacent to the fresh PD fluid inlet of the filter set. The one or more hydrophobic membranes allow air to be vented to the atmosphere before fresh PD fluid flows through the filter membranes.

[0035] In a first aspect of the present disclosure, which in light of the disclosure set forth herein is in no way limiting to the present disclosure but which may be combined with any other aspect or portion thereof, a peritoneal dialysis ("PD") system includes a PD machine, a patient line extending from the PD machine, and a filter set in fluid communication with the patient line, the filter set including a filter body housing first and second filter membranes, the filter body being configured to be arranged in different arrangements such that fresh PD fluid either (i) flows through the first filter membrane and then through the second filter membrane, or (ii) splits and flows in parallel through the first and second filter membranes.

[0036] In a second aspect of the present disclosure that can be combined with any other aspect or portion thereof, the filter body includes a first membrane module housing a first filter membrane, a second membrane module housing a second filter membrane, and a fluid spacer in fluid communication with the first and second membrane modules, the fluid spacer being configured to cause (i) or (ii).

[0037] In a third aspect of the present disclosure, which can be combined with any other aspect or portion thereof, the first membrane module is formed identically to the second membrane module.

[0038] In a fourth aspect of the present disclosure, which can be combined with any other aspect or portion thereof, with respect to (i), the fluid spacer is configured such that fresh PD fluid flows from the fluid spacer through a first filter membrane of a first membrane module, into a second membrane module, through the second filter membrane, and back to the fluid spacer before flowing to the patient.

[0039] In a fifth aspect of the present disclosure, which can be combined with any other aspect or part thereof, regarding (ii), the fluid spacer is configured such that fresh PD fluid splits from the fluid spacer into the first and second membrane modules, is filtered in parallel through the first and second filter membranes, and flows back into the fluid spacer before flowing to the patient.

[0040] In a sixth aspect of the present disclosure, which can be combined with any other aspect or portion thereof, the fluid spacer includes a patient lumen that allows fresh filtered PD fluid to flow to the patient and used PD fluid to flow from the patient.

[0041] In a seventh aspect of the present disclosure that can be combined with any other aspect or portion thereof, the fluid spacer includes a fresh PD fluid inlet with no outlet that receives fresh PD fluid from a patient line.

[0042] In an eighth aspect of the present disclosure that can be combined with any other aspect or portion thereof, the filter body includes a first membrane module housing a first filter membrane and a second membrane module housing a second filter membrane, the first and second membrane modules including a plurality of inlets, passages or lumens positioned and arranged to cause (i) and (ii), and a portion of the inlets, passages or lumens are blocked to cause (i) or (ii).

[0043] In a ninth aspect of the present disclosure, which can be combined with any other aspect or portion thereof, the first membrane module is formed identically to the second membrane module.

[0044] In a tenth aspect of the present disclosure that can be combined with any other aspect or portion thereof, at least one of the first or second membrane modules includes an upper compartment and a lower compartment, the upper compartment being formed the same as the lower compartment.

[0045] In an eleventh aspect of the present disclosure that can be combined with any other aspect or portion thereof, with respect to (i), the multiple inlets, passages or lumens are blocked such that fresh PD fluid flows through the first filter membrane of the first membrane module, into the second membrane module, and through the second filter membrane before flowing to the patient.

[0046] In a twelfth aspect of the present disclosure, which may be combined with any other aspect or portion thereof, regarding (ii), the multiple inlets, passages or lumens are blocked such that the fresh PD fluid splits into the first and second membrane modules and is filtered in parallel through the first and second filter membranes before flowing to the patient.

[0047] In a thirteenth aspect of the present disclosure that can be combined with any other aspect or portion thereof, the first and second membrane modules each include a patient lumen, and with respect to (ii), the patient lumen includes a bridge connector configured to divert fresh PD fluid from one of the patient lumens to the other of the patient lumens.

[0048] In a fourteenth aspect of the present disclosure that can be combined with any other aspect or portion thereof, the filter body includes a first membrane module housing a first filter membrane and a second membrane module housing a second filter membrane, the first and second membrane modules being stacked together, and the filter body further includes an inlet cover and an outlet cover, and at least one of the first and second membrane modules, the inlet cover and the outlet cover are configurable to cause (i) or (ii).

[0049] In a fifteenth aspect of the present disclosure, which can be combined with any other aspect or portion thereof, the first membrane module and the second membrane module use at least one of a first frame that forces all of the incoming fresh PD fluid to be filtered through an associated first or second filter membrane, or a second frame that filters a portion of the incoming fresh PD fluid through an associated first or second filter membrane and allows another portion of the incoming fresh PD fluid to bypass the associated first or second filter membrane.

[0050] In a sixteenth aspect of the present disclosure, which can be combined with any other aspect or portion thereof, the patient line is a dual lumen patient line including a fresh PD fluid lumen arranged in fluid communication with the fresh PD fluid port of the filter set, and the dual lumen patient line further includes a used PD fluid lumen arranged in fluid communication with the used PD fluid port of the filter set.

[0051] In a seventeenth aspect of the present disclosure, which may be combined with any other aspect or portion thereof, the filter set is configured to connect directly to a patient transfer set, or the filter set includes a flexible tube configured to connect to a patient transfer set.

[0052] In an eighteenth aspect of the present disclosure, which can be combined with any other aspect or portion thereof, the PD machine includes a pressure sensor positioned and arranged to sense the pressure of fresh PD fluid downstream of the filter membrane during patient fill.

[0053] In a nineteenth aspect of the present disclosure that can be combined with any other aspect or portion thereof, the first and second filter membranes are sterilizing grade or bacterial reducing filter membranes.

[0054] In a twentieth aspect of the present disclosure that can be combined with any other aspect or portion thereof, a peritoneal dialysis ("PD") system includes a PD machine, a patient line extending from the PD machine, and a filter set in fluid communication with the patient line, the filter set including a filter body and at least one of a first membrane or a second filter membrane, the filter bodies being configured to be arranged in different arrangements such that fresh PD fluid (i) flows through the first filter membrane and then through the second filter membrane, (ii) splits and flows in parallel through the first and second filter membranes, or (iii) flows only through the first filter membrane.

[0055] In a twenty-first aspect of the present disclosure, which may be used in conjunction with any other aspect or portion thereof, any of the features, functions, and alternatives described in association with any one or more of Figures 1 to 17 may be combined with any of the features, functions, and alternatives described in association with any other of Figures 1 to 17.

[0056] In light of the above aspects and the disclosure described herein, it is an advantage of the present disclosure to provide a modular filter set.

[0057] Another advantage of the present disclosure is that it provides filter sets that are adaptable to meet different sterilization needs.

[0058] Yet another advantage of the present disclosure is providing a filter set that can be configured to provide redundant disinfection.

[0059] A further advantage of the present disclosure is to provide a filter set that filters fresh PD fluid and allows spent PD fluid to pass through the filter membrane without clogging.

[0060] A further advantage of the present disclosure is that it provides a filter set with filtration capacity that is easily adjustable to suit different pathogen load needs.

[0061] Yet another advantage of the present disclosure is providing a filter set that operates with a dual lumen patient line.

[0062] Further features and advantages are described in and will be apparent from the following detailed description and drawings. The features and advantages described herein are not all-inclusive, and in particular many further features and advantages will be apparent to those skilled in the art in view of the drawings and description. Also, any particular embodiment need not have all of the advantages listed herein, and it is expressly contemplated that each advantageous embodiment may be separately claimed. Furthermore, it should be noted that the language used in this specification has been selected primarily for ease of reading and explanation purposes, and is not intended to limit the scope of the inventive subject matter. [Brief description of the drawings]

[0063] [Figure 1] FIG. 1 is a schematic diagram of one embodiment of a peritoneal dialysis system including a dual lumen patient line operating with a modular filter set of the present disclosure.

[0064] [Diagram 2] FIG. 2 is a perspective view of a first primary embodiment of a modular patient line filter set of the present disclosure.

[0065] [Diagram 3] FIG. 3 is a perspective view of a redundant version of the first primary embodiment of the modular patient line filter set of the present disclosure.

[0066] [Figure 4] FIG. 4 is a perspective view of a dual filter membrane version of the first primary embodiment of the modular patient line filter set of the present disclosure.

[0067] [Diagram 5] FIG. 5 is a perspective view of a single filter membrane version of the first primary embodiment of the modular patient line filter set of the present disclosure.

[0068] [Figure 6] FIG. 6 is a perspective view of a second primary embodiment of a modular patient line filter set of the present disclosure.

[0069] [Figure 7] FIG. 7 is a perspective view of a redundant version of the second primary embodiment of the modular patient line filter set of the present disclosure.

[0070] [Figure 8] FIG. 8 is a perspective view of a dual filter membrane version of the second primary embodiment of the modular patient line filter set of the present disclosure.

[0071] [Figure 9] FIG. 9 is a perspective view of one embodiment of a bridge connector for use with the dual filter membrane version of the second main embodiment of the modular patient line filter set of the present disclosure.

[0072] [Figure 10] FIG. 10 is a perspective view of a single filter membrane version of the second primary embodiment of the modular patient line filter set of the present disclosure.

[0073] [Figure 11] FIG. 11 is an assembled perspective view of the third primary embodiment of the modular patient line filter set of the present disclosure.

[0074] [Figure 12] FIG. 12 is an exploded perspective view of a third primary embodiment of the modular patient line filter set of the present disclosure.

[0075] [Figure 13] FIG. 13 is a perspective view of a membrane module having a first frame configured to filter all incoming fresh peritoneal dialysis ("PD") fluid.

[0076] [Figure 14] FIG. 14 is a perspective view of a membrane module having a second frame configured to filter some incoming fresh PD fluid and allow other incoming fresh PD fluid to bypass a filter membrane associated with the second frame.

[0077] [Figure 15] FIG. 15 is a cross-sectional perspective view of a redundant version of the third primary embodiment of the modular patient line filter set of the present disclosure.

[0078] [Figure 16] FIG. 16 is a cross-sectional perspective view of a dual filter membrane version of the third primary embodiment of the modular patient line filter set of the present disclosure.

[0079] [Figure 17] FIG. 17 is a cross-sectional perspective view of a single filter membrane version of the third primary embodiment of the modular patient line filter set of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0080] Detailed Description Referring now to the drawings, and in particular to FIG. 1, a peritoneal dialysis ("PD") system 10 is shown. The PD system 10 includes a PD machine or cycler 20 that pumps fresh PD fluid to a patient P through a patient line 50 and removes spent PD fluid from the patient P via the patient line 50. The patient line 50 may be reusable or disposable, and in either case operates with and is in fluid communication with a modular filter set 100, which may alternatively be referred to as a bacterial reduction filter set. If the patient line 50 is reusable, the reusable patient line is connected to the modular filter set 100 at the time of treatment. If the patient line 50 is instead disposable, in one embodiment, the modular filter set 100 is merged or formed into the disposable patient line 50. In either configuration, the distal end of the modular filter set 100 may be connected to a patient transfer set 58, which is in turn in fluid communication with the patient P's indwelling catheter.

[0081] The PD machine or cycler 20 can include a housing 22 with a durable PD fluid pump 24 that pumps the PD fluid through the pump itself without the use of disposable parts. Examples of durable pumps that can be used for the PD fluid pump 24 include piston pumps, gear pumps, and centrifugal pumps. Certain durable pumps, such as piston pumps, are inherently accurate such that the machine or cycler 20 does not require additional volume control components. Other durable pumps, such as gear pumps and centrifugal pumps, may be less accurate such that the machine or cycler 20 provides a volume control device such as one or more flow meters (not shown).

[0082] Alternatively, pump 24 may be a disposable type PD fluid pump that includes pump actuators that actuate disposable fluid-contacting pumping components such as peristaltic pump tubing or flexible pumping chambers. Examples of disposable PD fluid pumps that may be used for PD fluid pump 24 include rotary or linear peristaltic pump actuators that actuate tubing, pneumatic pump actuators that actuate cassette seats, electromechanical pump actuators that actuate cassette seats, and platen pump actuators that actuate tubing. While a single PD fluid pump 24 may be used, it should be understood that dedicated fresh and used PD fluid pumps may alternatively be used. Additionally, a single PD fluid pump 24 may include multiple pumping chambers for a more continuous flow of PD fluid.

[0083] The PD machine or cycler 20 may also include a number of valves 26a, 26b, 26m, 26n, which may also be flow-through and durable, not operating with disposable components, or disposable type valves with valve actuators that actuate disposable fluid-contacting valve components, such as tubing segments or cassette-based valve seats. Examples of durable valves that may be used for the valves 26a, 26b, 26m, 26n include flow-through solenoid valves. Such valves may be two-way or three-way valves. Examples of disposable valves that may be used for the valves 26a, 26b, 26m, 26n include solenoid pinch valves that pinch closed flexible tubing, pneumatic valve actuators that actuate cassette seats, and electromechanical valve actuators that actuate cassette seats.

[0084] Machine or cycler 20 will likely include a number of valves 26a-26n. For ease of illustration, machine or cycler 20 is shown as having fresh PD fluid valve 26a that is controlled to open to allow PD fluid pump 24 to pump fresh PD fluid under positive pressure through fresh PD fluid lumen 52 of dual lumen patient line 50 to patient P. The valves also include spent PD fluid valve 26b that is controlled to open to allow PD fluid pump 24 to draw spent PD fluid from patient P under negative pressure through spent PD fluid lumen 54 of dual lumen patient line 50. Valve 26m is provided to allow selective access to one or more PD fluid sources, while valve 26n is provided to allow selective access to a drain, such as a waste container or house drain, via drain line 60.

[0085] The machine or cycler 20 in the illustrated embodiment also includes pressure sensors, such as pressure sensors 28a, 28b. Pressure sensor 28a is located immediately downstream of fresh PD fluid valve 26a, and pressure sensor 28b is located immediately upstream of spent PD fluid valve 26b. Thus, even when fresh PD fluid valve 26a is closed, pressure sensor 28a can sense the pressure in the new PD fluid lumen 52 of the double lumen patient line 50, while even when spent PD fluid valve 26b is closed, pressure sensor 28b can sense the pressure in the used PD fluid lumen 54 of the double lumen patient line 50. Additionally, pressure sensor 28a is positioned to sense the pressure of the fresh PD fluid upstream of the filter membrane discussed herein during patient fill. Pressure sensor 28b, perhaps more importantly, is positioned to sense the pressure of the fresh PD fluid downstream of the filter membrane discussed herein during patient fill, thus taking into account the pressure drop due to multiples (if redundant).

[0086] The pump 24 and valves 26a, 26b in the illustrated embodiment are automatically controlled by a control unit 40 provided by the device or cycler 20 of the system 10, and outputs from the pressure sensors 28a, 28b (and other sensors) are provided to the control unit 40. The control unit 40 in the illustrated embodiment includes one or more processors 42, one or more memories 44, and a video controller 46. The control unit 40 receives, stores and processes signals or outputs from the pressure sensors 28a, 28b and other sensors provided by the machine or cycler 20, such as one or more temperature sensors 30 and one or more conductivity sensors (not shown). The control unit 40 can use pressure feedback from one or more of the pressure sensors 28a, 28b to control the PD fluid pump 24 to pump dialysis fluid at a desired pressure or within safe pressure limits (e.g., within 0.21 bar (3 psig) of the positive pressure to the patient's peritoneal cavity and within -.10 bar (-1.5 psig) of the negative pressure from the patient's peritoneal cavity).

[0087] Control unit 40 uses temperature feedback from one or more temperature sensors 30 to control heater 32, such as an in-line heater, to heat fresh PD fluid to a desired temperature, such as body temperature or 37° C. In one embodiment, heater 32 is further used to heat a disinfectant fluid, such as fresh PD fluid, to disinfect PD fluid pump 24, valves 26a through 26n, heater 32, and all reusable fluid lines within device or cycler 20 and prepare the device or cycler for the next procedure. Additional filtration as discussed herein provides a layer of protection in addition to heated fluid disinfection to ensure that the PD fluid is safe for delivery to patient P.

[0088] The video controller 46 of the control unit 40 interfaces with a user interface 48 of the machine or cycler 20, which may include a display screen operated with one or more electromechanical buttons, such as a touch screen and / or membrane switches. The user interface 48 may also include one or more speakers for outputting alarms, warnings, and / or voice guidance commands. The user interface 48 may be provided with the machine or cycler 20 as shown in FIG. 1 and / or may be a remote user interface operating with the control unit 40. The control unit 40 may also include a transceiver (not shown) and a wired or wireless connection to a network, e.g., the Internet, for transmitting treatment data to and receiving prescription orders from a physician or clinician server that interfaces with a physician or clinician's computer.

[0089] 1 , the modular filter set 100 in one embodiment includes a lumen connector 104, a transferset connector 106, an optional short flexible tube 108, and a filter body 110, 150, or 190. The short flexible tube 108 is positioned between the filter body 110, 150, or 190 and the patient's transferset 58 such that the generally rigid filter body 110, 150, or 190 of the filter set 100 is spaced from the generally rigid transferset 58 to aid in patient comfort. That is, a directly abutted filter body 110, 150, or 190 and transferset 58 can create a combined rigid structure that is uncomfortable for the patient during sleep.

[0090] The lumen connector 104, the transferset connector 106, and the filter body 110, 150, or 190 may be molded together from one or more pieces, ultrasonically, via heat sealing, and / or adhesively, for example, via solvent bonding. The lumen connector 104, the transferset connector 106, the optional short flexible tube 108, and any of the filter bodies 110, 150, or 190 may be made of any one or more plastics, such as polystyrene ("PS"), polycarbonate ("PC"), a blend of polycarbonate and acrylonitrile-butadiene-styrene ("PC / ABS"), polyvinyl chloride ("PVC"), polyethylene ("PE"), polypropylene ("PP"), a polyester such as polyethylene terephthalate ("PET"), or polyurethane ("PU").

[0091] The lumen side connector 104 may include a fresh PD fluid port (not shown) for communicating with the fresh PD fluid lumen 52 of the dual lumen patient line 50 and a spent PD fluid port (not shown) for communicating with the spent PD fluid lumen 54 of the dual lumen patient line 50. The fresh and spent PD fluid ports may be surrounded by a shroud (not shown) of the lumen side connector 104, which may be formed with threads (not shown) for mating with mating threads of the patient line connector 56. In one embodiment, threading of the patient line connector 56 into the lumen side connector 104 seals the mating ports (not shown) of the patient line connector 56 against the fresh and spent PD fluid ports of the lumen side connector 104 via one or more compressible gaskets (not shown), such as, for example, silicone or other suitable rubber gaskets. The shroud of the lumen side connector 104 may be keyed. The patient line connector 56 is matingly keyed so that the patient line connector can only be introduced into the shroud in the proper orientation to align the fresh PD fluid lumen 52 with the fresh PD fluid port and the spent PD fluid lumen 54 with the used PD fluid port of the lumen side connector 104. If the dual lumen patient line 50 is disposable, the lumen side connector 104 can alternatively simply include ports, for example, a fresh PD fluid port and a used PD fluid port, through which the fresh PD fluid lumen 52 and the spent PD fluid lumen 54, respectively, extend to seal to the ports in any manner described herein.

[0092] The transferset connector 106 connects directly to a mating connector on the patient's transferset 58 (if no tubing 108 is provided) or directly to a mating connector on a short length of flexible tubing 108 disposed between the filter housing 102 and the patient's transferset 58. The transferset connector 106 may include a port and a threaded shroud (not shown) for a luer-type connection to the mating connector. Alternatively, the transferset connector 106 may be a port through which the short length of flexible tubing 108 extends to seal to a port in any manner described herein.

[0093] 2-5, the filter body 110 in the first primary embodiment of the present disclosure is shown in more detail. The filter body 110 is shown in a generally rectangular format, but may have any desired and / or optimized shape. The filter body 110 in the illustrated embodiment includes a pair of membrane modules 120a, 120b. The membrane modules 120a, 120b are similarly configured in one embodiment to aid in modularity of the filter set 100 and system 10.

[0094] 2 shows that membrane modules 120a, 120b each include an upper compartment 122 and a lower compartment 124. Filter membrane 112a is located between the upper compartment 122 and the lower compartment 124 of membrane module 120a, such that fresh PD fluid in the upper compartment 122 is separated from fresh PD fluid in the lower compartment 124 by filter membrane 112a. Filter membrane 112b is similarly located between the upper compartment 122 and the lower compartment 124 of membrane module 120b, such that fresh PD fluid in the upper compartment 122 is separated from fresh PD fluid in the lower compartment 124 by filter membrane 112b.

[0095] The filter membranes 112a and 112b in the illustrated embodiment are provided in the form of flat sheets that can bisect the membrane modules 120a and 120b, respectively. The filter membranes 112a and 112b can be sterilizing grade or bacteria reducing hydrophilic membranes that can be formed with porous walls having pore sizes of about 0.2 microns through which the fresh PD fluid flows for further filtration. The filter membranes 112a and 112b can be made of, for example, polysulfone or polyethersulfone blended with polyvinylpyrrolidone. As described below, the filter membranes 112a and 112b are formed such that the fresh PD fluid can be filtered through the membrane in either a top-to-bottom or bottom-to-top direction.

[0096] The hydrophilic nature of the filter membranes 112a, 112b prevents air from migrating across them once they are fully wetted with fresh PD fluid, thus serving the secondary end-stage air removal purpose. However, if desired, any of the embodiments described herein contemplate one or more hydrophobic membranes (not shown) upstream of the first filter membrane 112a (from the perspective of the fresh PD fluid). The one or more hydrophobic membranes allow air to escape to the atmosphere before the fresh PD fluid flows through either of the filter membranes 112a, 112b. The hydrophobic membranes may be constructed, for example, from polytetrafluoroethylene ("PTFE").

[0097] 3 and 4 both show that a fluid passageway 126 extends from the upper compartment 122 of the membrane modules 120a, 120b through the outer wall of the upper compartment. A fluid passageway 128 extends from the lower compartment 124 of the membrane modules 120a, 120b through the outer wall of the lower compartment. Thus, fresh PD fluid can flow into or out of the upper compartment 122 and lower compartment 124 via the fluid passageways 126 and 128, respectively.

[0098] Different fresh PD flow paths through the modular filter body 110 are provided by differently configured fluid spacers 130a-130c. Fluid spacer 130a is shown in Figures 2 and 3, while fluid spacer 130b is shown in Figure 4 and fluid spacer 130c is shown in Figure 5. Once the desired fluid spacer 130a-130c is selected, the upper and lower compartments 122 and 124 may be sealed together at once, such as, for example, via solvent bonding, ultrasonically sealed, heat sealed and / or adhesively sealed to the selected fluid spacer 130a-130c, such as, for example, via solvent bonding. The modular filter set 100 may alternatively be formed in stages, for example, the membrane modules 120a, 120b may be formed separately and then ultrasonically sealed, heat sealed and / or adhesively sealed to the selected fluid spacer 130a-130c, such as, for example, via solvent bonding.

[0099] The fluid spacer 130a shown in FIG. 3 includes or defines a fresh PD fluid inlet 132 and a patient lumen 134. The fresh PD fluid inlet 132 may extend from or be in fluid communication with, for example, a fresh PD fluid port of the lumen connector 104, and the patient lumen 134 may extend from or be in fluid communication with, for example, a used PD fluid port of the lumen connector 104. The fresh PD fluid inlet 132 in the illustrated embodiment is formed as a blind lumen that does not completely penetrate the back surface of the fluid spacer 130a. Meanwhile, the patient lumen 134 extends through the back surface of the fluid spacer 130a, for example, to transport the set connector 106.

[0100] The fluid spacer 130a shown in FIG. 3 further includes or defines three fluid channels that set the direction of flow of fresh PD fluid through the modular filter body 110. The fluid spacer 130a includes or defines an upper cross channel 136 that extends between the fluid passages 126 formed in the upper compartments 122 of the membrane modules 120a, 120b to allow fresh PD fluid to pass therebetween. The fluid spacer 130a includes or defines lumen channels 138a and 138b. The lumen channel 138a extends between the fluid passage 128 of the membrane module 120a and the fresh PD fluid inlet 132 to allow fresh PD fluid to flow therebetween. The lumen channel 138b extends between the fluid passage 128 of the membrane module 120b and the patient lumen 134 to allow fresh PD fluid to flow therebetween.

[0101] Fluid spacer 130a is a redundant spacer that allows fresh PD fluid entering the spacer through fresh PD fluid inlet 132 to flow through lumen channel 138a and fluid passage 128 into the lower compartment 124 of membrane module 120a. The fresh PD fluid is then filtered through filter membrane 112a into the upper compartment 122 of membrane module 120a (first filtration). Once filtered, the fresh PD fluid flows through fluid passage 126 and cross channel 136 into the upper compartment 122 of membrane module 120b. Once filtered, the fresh PD fluid then filters again through filter membrane 112b into the lower compartment 124 of membrane module 120b (redundant filtration). The twice filtered fresh PD fluid then flows from the lower compartment 124 of membrane module 120b through lumen channel 138b to patient lumen 134 and from patient lumen 134 to the patient for patient filling of PD therapy. The overall redundant modular filter set 100 is advantageous in that it provides the necessary sterilization even if one of the filter membranes 112a, 112b is compromised, and provides dual filtration when both filter membranes 112a, 112b are intact.

[0102] The fluid spacer 130b shown in FIG. 4 also includes or defines a fresh PD fluid inlet 132 and a patient lumen 134. The fresh PD fluid inlet 132 is also formed as a blind lumen that does not completely penetrate the back of the fluid spacer 130b. Meanwhile, the patient lumen 134 extends through the back of the fluid spacer 130a, for example to transport the set-side connector 106. The fluid spacer 130b shown in FIG. 4 includes or defines two fluid channels that set the direction of the flow of fresh PD fluid through the modular filter body 110. The fluid spacer 130b includes or defines a lumen channel 140 that extends between the patient lumen 134 and both fluid passages 126 of both membrane modules 120a, 120b and allows the fresh PD fluid to flow therebetween. The fluid spacer 130b also includes or defines a lumen channel 142 that extends between the PD fluid inlet 132 and both fluid passageways 128 of both membrane modules 120a, 120b to allow fresh PD fluid to flow therebetween.

[0103] Fluid spacer 130b is a dual membrane spacer that instead splits fresh PD fluid entering the spacer via PD fluid inlet 132 to flow in two opposite directions simultaneously or in parallel through lower lumen channel 142 and fluid passageway 128 to the lower compartment 124 of both membrane modules 120a, 120b. Fresh PD fluid is then filtered from the lower compartment 124 through both filter membranes 112a, 112b simultaneously or in parallel to the upper compartment 122 of both membrane modules 120a, 120b. The filtered fresh PD fluid then flows through lumen channel 140 to patient lumen 134 and from patient lumen 134 to the patient for patient loading of PD therapy. Dual membrane modular filter set 100 is advantageous in that it effectively doubles the flow capacity of the filter set compared to a similarly sized filter set using fluid spacer 130a.

[0104] The fluid spacer 130c shown in FIG. 5 operates with only a single membrane module 120b. The fluid spacer 130c also includes or defines a fresh PD fluid inlet 132 and a patient lumen 134. The fresh PD fluid inlet 132 is also formed as a blind lumen that does not completely penetrate the back of the fluid spacer 130b. Meanwhile, the patient lumen 134 extends through the back of the fluid spacer 130a, for example to transport the set-side connector 106. A lumen channel 144 extends between the patient lumen 134 and the upper compartment 122 of the membrane module 120b, allowing fresh PD fluid communication therebetween. A second lumen channel 146 extends between the PD fluid inlet 132 and the lower compartment 124 of the membrane module 120b, allowing fresh PD fluid communication therebetween.

[0105] Fluid spacer 130c is a single membrane spacer operating with a single membrane module 102b. Here, fresh PD fluid entering single membrane spacer 130c via PD fluid inlet 132 flows into lower compartment 124 of membrane module 120b via lumen channel 146 and fluid passage 128. The fresh PD fluid is then filtered through filter membrane 112b into upper compartment 122. The filtered fresh PD fluid then flows through fluid passage 126 and lumen channel 144 to patient lumen 134, from where it flows to the patient for patient filling of PD therapy. Single membrane modular filter set 100 is advantageous in terms of reducing size and cost.

[0106] 6-10, the filter body 150 of the second main embodiment of the present disclosure is shown in more detail. The filter body 150 is shown in a generally rectangular format, but may have any desired and / or optimized shape. The filter body 150 in the illustrated embodiment includes a pair of membrane modules 160a, 160b. The membrane modules 160a, 160b are, in one embodiment, constructed the same (at least initially) regardless of whether a redundant filter, a dual membrane filter, or a single membrane filter is provided to aid in modularity of the filter set 100 and system 10. The filter body 150 eliminates the spacers 130a-c associated with the filter body 110.

[0107] The membrane modules 160a, 160b are formed with the necessary openings (ports) and lumens or passages for each of the redundant, dual membrane and single membrane filter versions. The final or subsequent manufacturing step for the modules 160a, 160b is to plug the unused openings (ports) and unneeded lumens or passages so that the desired overall flow path through the modular filter set 100 is created.

[0108] 6 shows that membrane modules 160a, 160b each include an upper compartment 162 and a lower compartment 164. Filter membrane 112a is located between upper compartment 162 and lower compartment 164 of membrane module 160a, such that fresh PD fluid in upper compartment 162 is separated from fresh PD fluid in lower compartment 164 by filter membrane 112a. Filter membrane 112b is similarly located between upper compartment 162 and lower compartment 164 of membrane module 160b, such that fresh PD fluid in upper compartment 162 is separated from fresh PD fluid in lower compartment 164 by filter membrane 112b. Filter membranes 112a, 112b are again formed such that fresh PD fluid can be filtered through the membrane in either a top-to-bottom or bottom-to-top direction.

[0109] Both Figures 6 and 7 show the necessary openings (ports) and lumens or passages for the redundant, dual membrane and single membrane filter versions, respectively. In particular, the upper compartment 162 of the membrane modules 160a, 160b in the illustrated embodiment includes a fresh PD fluid inlet 166. The fresh PD fluid inlet 162 may extend from or be in fluid communication with, for example, a fresh PD fluid port of the lumen side connector 104. The fresh PD fluid inlet 162 in the illustrated embodiment can be formed as (i) a blind lumen that does not completely penetrate the rear of the membrane module (the modules 160a, 160b are formed as a left and right pair), or (ii) a through-hole lumen where the back end of the lumen is plugged or blocked, effectively forming a blind lumen. The upper compartment 162 of the membrane modules 160a, 160b in the illustrated embodiment also includes a fluid passage 168 that allows the fresh PD fluids in the upper compartments 162 to be in fluid communication with each other. It should be noted that the lower compartment 164 also includes a fluid passage 168 which is always blocked in the lower compartment, but which does not have to be blocked when a modular component is used instead as the upper compartment 162, allowing a single modular component to be manufactured.

[0110] The lower compartment 164 of the membrane modules 160a, 160b in the illustrated embodiment includes a patient lumen 170. The patient lumen 170 extends through the lower compartment 164 and can operate as a fresh PD fluid inlet from the patient line 50 or as a fresh PD fluid outlet to the patient, for example in fluid communication with the transfer set connector 106. The patient lumen 170 can further be used to carry spent PD fluid removed from the patient. The lower compartment 164 of the membrane modules 160a, 160b in the illustrated embodiment also includes a fluid passageway 172 extending from the patient lumen 170 to a fluid holding area of ​​the lower compartment 164, allowing fresh PD fluid to flow in either direction between the patient lumen 170 and the lower compartment. A fluid passageway 172 is also provided in the upper compartment 162 that extends from the fresh PD fluid inlet 166 to the fluid holding area of ​​the upper compartment 162, allowing fresh PD fluid to flow in either direction between the PD fluid inlet 166 and the upper compartment.

[0111] It should be understood that a single molded part can operate as any of the four separate parts of the filter body 150 shown in Figures 6 and 7. Once the filter membranes 112a and 112b are inserted between the upper and lower compartments 162, 164 and the necessary plugs are inserted, e.g., glued, the four separate parts can be sealed together at once, e.g., ultrasonically, heat-sealed and / or adhesively sealed, e.g., via solvent bonding. The modular filter set 100 may alternatively be formed in stages, e.g., the membrane modules 160a, 160b are formed separately with plugs in place and then ultrasonically, heat-sealed and / or adhesively sealed together, e.g., via solvent bonding.

[0112] 6 and 7 show a redundant configuration of filter body 150, where fresh PD fluid inlet 166 in upper compartment 162 and fluid passageway 168 in lower compartment 164 of both modules 160a, 160b are fully blocked (fresh PD fluid inlet 166 is blocked to cover at least fluid passageway 172). The latter half of patient lumen 170 in membrane module 160a is blocked to not cover fluid passageway 172. Patient lumen 170 and fluid passageway 168 in upper compartment 162 in membrane module 160b remain fully open and unblocked.

[0113] With this configuration, fresh PD fluid entering the patient lumen 170 of membrane module 160a flows through fluid passage 172 to the lower compartment 164 of membrane module 160a. The fresh PD fluid is then filtered through filter membrane 112a into the upper compartment 162 of membrane module 160a (first filtration). Once filtered, the fresh PD fluid flows into the fluid holding portion 162 of membrane module 160b through fluid passages 168 of both upper compartments. Once filtered, the fresh PD fluid then filters again through filter membrane 112b into the lower compartment 164 of membrane module 160b (redundant filtration). The twice filtered fresh PD fluid then flows from the lower compartment 164 of membrane module 160b through fluid passage 172 to the patient lumen 170 in membrane module 160b and from the patient lumen 170 to the patient for patient filling of PD therapy. It should be understood that while fresh PD fluid in patient lumen 170 in membrane module 160b could theoretically flow out the front of patient lumen 170 and into spent PD fluid lumen 54, spent PD fluid lumen 54 is a closed stationary line due to the closure of spent PD fluid valve 26b, forcing fresh PD fluid to flow in the opposite direction toward the patient. The overall redundant modular filter set 100 using filter body 150 is advantageous in that it provides the necessary sterilization even if one of filter membranes 112a, 112b is compromised, and provides dual filtration when both filter membranes 112a, 112b are intact.

[0114] 8 and 9 show a dual membrane configuration of filter body 150, where fresh PD fluid inlet 166 in upper compartment 162 of membrane module 160b and fluid passageway 168 in lower compartment 164 of both membrane modules 160a, 160b are fully blocked (fresh PD fluid inlet 166 of membrane module 160b is blocked covering at least fluid passageway 172). The rear half of patient lumen 170 in membrane module 160b is blocked so as not to cover fluid passageway 172. Fluid passageway 168 in upper compartment 162 of both membrane modules 160a, 160b remains fully open and unblocked.

[0115] Attached to the front of the patient lumen 170 of membrane modules 160a and 160b is a bridge connector 180, shown in FIG. 9. The bridge connector 180 is formed, e.g., molded, from any of the materials described herein. The bridge connector 180 includes legs 182 that are ultrasonically sealed, heat sealed, and / or adhesively sealed, e.g., via solvent bonding, to the inner surface of the patient lumen 170. The common port of the bridge connector 180 forms the spent PD fluid port 104u of the lumen side connector 104 (FIG. 1). The bridge connector 180 allows fresh PD fluid to flow from the patient lumen 170 of membrane module 160b to the patient lumen 170 of membrane module 160a, so that all fresh PD flows out the rear of the patient lumen 170 of membrane module 160a to the patient. Again, although it is theoretically possible for fresh PD fluid to flow out of spent PD fluid port 104u into spent PD fluid lumen 54, spent PD fluid lumen 54 is a closed static line due to the closure of spent PD fluid valve 26b, forcing the fresh PD fluid to flow in the opposite direction toward the patient.

[0116] The dual membrane configuration of Figures 8 and 9 allows fresh PD fluid entering through the fresh PD fluid inlet 166 of the membrane module 160a to flow through the upper compartment 162 of the membrane module 160a and the upper fluid passage 168 into the upper compartment 162 of the membrane module 160b. The fresh PD fluid is pressurized in both upper compartments 162 and then simultaneously or in parallel filtered through both filter membranes 112a, 112b into the lower compartments 164 of both membrane modules 160a, 160b. The filtered fresh PD fluid then flows through fluid passage 172 into the patient lumen 170 and from there to the patient via the bridge connector 180 as previously described for patient loading of PD therapy. The dual membrane modular filter set 100 using the filter body 150 is advantageous because it effectively doubles the flow capacity of the filter set.

[0117] 10 shows a single membrane configuration of filter body 150. Here, only a single membrane module is used, e.g., membrane module 160b. Fluid passages 168 in upper compartment 162 and lower compartment 164 are blocked. The rear or back of fresh PD fluid inlet 166 in upper compartment 162 is also blocked, but leaves fluid passage 172 open. Patient lumen 170 in lower compartment 174 leaves the lower compartment completely open to allow spent PD fluid to flow from the patient to spent PD fluid lumen 54.

[0118] The single membrane configuration of FIG. 10 allows fresh PD fluid entering the fresh PD fluid inlet 166 of the upper compartment 162 to flow through the fluid passage 172 into the fluid receiving portion of the upper compartment 162. The fresh PD fluid is then filtered through the filter membrane 112b into the lower compartment. The filtered fresh PD fluid then flows through the fluid passage 172 into the patient lumen 170 and from there to the patient for patient filling of PD therapy. Again, although it is theoretically possible for fresh PD fluid to flow from the patient lumen 170 into the spent PD fluid lumen 54, the spent PD fluid lumen 54 is a closed stationary line due to the closure of the spent PD fluid valve 26b, forcing the fresh PD fluid to flow in the opposite direction toward the patient. The single membrane modular filter set 100 using the filter body 150 is advantageous in terms of reducing size and cost.

[0119] 11-17, the filter body 190 of the third main embodiment of the present disclosure is shown in more detail. FIGS. 11 and 12 show that in the third main embodiment using the filter body 190, the modular filter set 100 eliminates the spacers 130a-130c associated with the filter body 110 and stacks the membrane modules 210a, 210b...210n. Inlet and outlet covers 192, 200 are also provided. The inlet cover 192 includes or defines a shell 194 that provides a space for fresh PD fluid to distribute across the shell before being filtered through the filter membrane. A fresh PD fluid inlet 196 is formed in the shell 194 and extends to the fresh PD fluid port 104f of the lumen side connector 104 (FIG. 1). Although not visible in FIGS. 11 or 12, the shell 194 defines an opening that allows fresh PD fluid to flow from the fresh PD fluid inlet 196 to the open space defined by the shell 194.

[0120] The outlet cover 200 similarly includes or defines a shell 202 that provides space for the distribution of filtered fresh or spent PD fluid throughout the shell before either (i) flowing as fresh PD fluid through the patient lumen 204 and the transfer set connector 106 to the patient, or (ii) flowing as spent PD fluid through the patient lumen 204 and the spent PD fluid port 104u ( FIG. 1 ) of the lumen connector 104 to the spent PD fluid lumen 54. In one embodiment, the patient lumen 204 is formed from the shell 202. As shown in FIG. 12 , the shell 202 defines an opening 206 that allows the filtered fresh PD fluid to flow from the shell 202 to the patient lumen 204 on its way to the patient via the transfer set connector 106. It should be understood that while spent PD fluid could theoretically flow from the patient lumen 204 into the shell 202 through the opening 206, the negative pressure applied to the spent PD fluid port 104u to remove the spent PD fluid from the patient provides little incentive for the spent PD fluid to do so.

[0121] Each of the membrane modules 210a, 210b...210n includes a frame 212a or 212b that defines an opening 214. The opening 214 in the illustrated embodiment is partially filled with support ribs 216 that support the filter membranes 112a, 112b. The ribs 216 do not completely block the opening 214, thus allowing fresh PD fluid to be filtered from the inlet cover 192 across the filter membranes 112a, 112b. The filter membranes 112a, 112b are ultrasonically sealed, heat sealed, and / or adhesively sealed, e.g., via solvent bonding, to the inner periphery of the frame 212a or 212b such that they cover the opening 214 and are supported by the ribs 216. After the desired number of membrane modules 210a, 210b...210n are stacked together (which may be only a single module or two or more modules), the inlet and outlet covers 192, 200 are fitted to the exposed faces of one or more membrane modules 210a, 210b...210n, and then the modules and covers are ultrasonically sealed, heat sealed and / or adhesively sealed, for example via solvent bonding, to form the modular filter set 100 of the third main embodiment.

[0122] Figure 13 shows frame 212a in greater detail, and Figure 14 shows frame 212b in greater detail. Frames 212a and 212b each define an opening 214 that is partially filled with support ribs 216 that support filter membranes 112a, 112b. The opening 214 for frame 212a is defined by a perimeter 218a from which the support ribs 216 extend. The opening 214 for frame 212b is defined by a perimeter 218b from which the support ribs 216 extend.

[0123] The perimeter 218a of the frame 212a is solid so that all fresh PD fluid entering from left to right is forced over the filter membranes 112a, 112b and then between the support ribs 216. The frame 212a is open below the ribs 216 so that the fresh PD fluid filtered through the filter membranes 112a, 112b extends to any structure below the frame 212a, such as a second frame 212b (FIG. 15) or the outlet cover 200 (FIG. 17).

[0124] Instead, the periphery 218b of the frame 212b includes an inlet opening 220 and an outlet opening 222. The inlet opening 220 allows incoming fresh PD fluid to be split between (i) pushing through the top of the filter membranes 112a, 112b and then between the support ribs 216 and (ii) bypassing the filter membranes and flowing through the inlet opening 220 downward, for example, to the second lower frame 212b (FIG. 16). The frame 212b does not open below the support ribs 216, but instead includes a bottom 224 (FIGS. 15 and 16) that captures the filtered fresh PD fluid and allows the filtered fluid to flow across the frame 212b and out through one or more openings 226 to the outlet opening 222. The filtered fresh PD fluid then flows from the outlet opening 222 either (i) to one or more other outlet openings 222 in the second frame 212b and then to the outlet cover 200 (Figure 16), or (ii) directly to the outlet cover 200 (Figure 15).

[0125] 15 shows that a redundant modular filter set 100 is formed using the body 190 such that fresh PD fluid entering a first membrane module 210a of the stack (having frame 212a) through the inlet cover 192 is filtered through the filter membrane 112a of the membrane module 210a (first filtration), flows to a second membrane module 210b of the stack (also having frame 212a), is filtered through the filter membrane 112b of the second membrane module 210b (redundant filtration), and flows out of the second membrane module 210b through the outlet opening 222 of the second frame 212a and opening 206 in the shell 202 into the patient lumen 204 of the outlet cover 200 and to the patient through the transfer set connector 106. Spent PD fluid flows from the patient back to the spent PD fluid lumen 54 (FIG. 1) through the transfer set connector 106, the patient lumen 204, and the spent PD fluid port 104u. The overall redundant modular filter set 100 using the body 190 is similarly advantageous as it mitigates compromised filter membranes and provides dual filtration when both filter membranes are intact.

[0126] In an alternative embodiment of the redundant modular filter set 100 using the body 190 of FIG. 15, the second membrane module 210b of the stack instead includes a frame 212b, and the twice-filtered fresh PD fluid instead flows along the top surface of the bottom 224 of the frame 212b and through the opening 206 in the shell 202 to the patient lumen 204.

[0127] 16 shows that a dual membrane modular filter set 100 using the body 190 is instead formed such that fresh PD fluid entering through the inlet cover 192 flows in parallel to the top of both membrane modules 210a (with frame 212b), 210b (also with frame 212b) and is filtered simultaneously or in parallel through both filter membranes 112a, 112b. It should be appreciated that the associated flow into the outlet opening 222 through the bottom 224 and opening 226 of the frame 212b prevents PD fluid entering the top membrane module 210a from being filtered twice through both filter membranes 112a, 112b. The filtered PD fluid flows from the outlet opening 222 of the frame 212b to the patient lumen 204 of the outlet cover 200 and then through the patient lumen 204 and the transfer set connector 106 to the patient. The spent PD fluid returns from the patient through the transfer set connector 106, the patient lumen 204, and the spent PD fluid port 104u to the spent PD fluid lumen 54. The entire dual membrane modular filter set 100 using the body 190 also advantageously doubles the flow capacity of the filter set.

[0128] In an alternative embodiment, to allow the membrane modules 210a, 210b to be manufactured in the same way and have only a single frame, it is contemplated that the inlet end of the single frame may be provided with one or more pluggable holes or openings (not shown) to allow the membrane modules 210a, 210b to operate in the redundant mode of FIG. 15 and the dual filter membrane mode of FIG. 16. One or more holes or openings are plugged in each of the upper and lower modules in the redundant version of FIG. 15, so that all incoming fresh PD fluid is forced to the top of the upper membrane module 210a. In the dual filter membrane version of FIG. 16, one or more holes or openings are not plugged in the upper module 210a but are plugged in the lower module 210b, so that the incoming fresh PD fluid is split between the upper membrane module 210a and the lower membrane module 210b. One or more holes or openings are also plugged in the membrane module 210a in the single filter version of FIG. 17.

[0129] 17 shows that a single membrane module filter set 100 using the body 190 uses a single membrane module 210a in combination with the inlet and outlet covers 192, 200. Here, the inlet covers 192, 200 and the outlet cover are sealed to a single membrane module 210a (with frame 212a), so that fresh PD fluid entering the membrane module through the inlet cover 192 flows into the inlet compartment under the shell 194 of the inlet cover 192, is uniformly filtered through the filter membrane 112a of the membrane module 210a into the outlet compartment formed by the shell 202 of the outlet cover 200, and flows out of the outlet compartment through the outlet opening 222 of the frame 212a and the opening 206 of the shell 202 into the patient lumen 204 of the outlet cover 200. The spent PD fluid flows back from the patient through the transfer set connector 106, the patient lumen 204, and the spent PD fluid port 104u back to the spent PD fluid lumen 54 (FIG. 1). The overall single membrane modular filter set 100 using the body 190 similarly reduces size and cost.

[0130] The spent PD fluid removed through the patient transfer section 58 of each of the above filter body embodiments under negative pressure from the PD fluid pump 24 enters the modular filter set 100 via the transfer set connector 106. The spent PD fluid then flows through the body 110, 150 or 190 provided through the corresponding patient lumen 134, 170, 204, through the spent PD fluid port 104u and the spent PD fluid lumen 54, and back to the PD machine or cycler 20. The PD machine or cycler 20 pumps the spent PD fluid under positive pressure from the PD fluid pump 24 to drain through the drain line 60. The majority of the spent PD fluid does not contact the underside of the filter membrane 112a, 112b in the body 110, 150 or 190. Thus, the filter membrane 112a, 112b remains viable over the course of multiple fills of processing before being discarded by the modular filter set 100.

[0131] It should be understood that various modifications and variations to the presently preferred embodiments described herein will be apparent to those skilled in the art. It is therefore intended that any or all such modifications and variations may be covered by the appended claims. For example, although a dual lumen patient line 50 is shown, a single lumen patient line may alternatively be provided.

Claims

1. A peritoneal dialysis ("PD") system (10) comprising: A PD machine (20); a patient line (50) extending from the PD machine (20); a filter set (100) in fluid communication with the patient line (50); Equipped with a filter set (100) including a filter body (110, 150, 190) containing first and second filter membranes (112a, 112b), the filter bodies (110, 150, 190) configured to be arranged in different arrangements so that fresh PD fluid (i) flows through the first filter membrane (112a) and then through the second filter membrane (112b), or (ii) flows in parallel and splits through the first and second filter membranes (112a, 112b), and the filter set (100) includes a fresh PD fluid inlet (132) and a fluid spacer (130a, 130b) configured to cause (i) or (ii) through a patient lumen (134).

2. 2. The PD system of claim 1, wherein the fluid spacers are in fluid communication with a first membrane module containing the first filter membrane and a second membrane module containing the second filter membrane.

3. The PD system (10) of claim 2, wherein the configuration of the first membrane module (120a) is the same as the configuration of the second membrane module (120b).

4. Regarding (i), the fluid spacer (130a) is configured to allow fresh PD fluid to flow from the fluid spacer (130a) through the first filter membrane (112a) of the first membrane module (120a), into the second membrane module (120b), through the second filter membrane (112b), and back into the fluid spacer (130a) before flowing to the patient.

5. Regarding (ii), the fluid spacer (130b) is configured so that fresh PD fluid splits from the fluid spacer (130a) into the first and second membrane modules (120a, 120b), is filtered in parallel through the first and second filter membranes (112a, 112b), and flows back into the fluid spacer (130b) before flowing to the patient.

6. The PD system (10) of any one of claims 1 to 3, wherein the fluid spacer (130a, 130b) includes the patient lumen (134) that allows filtered fresh PD fluid to flow to a patient and spent PD fluid to flow from the patient.

7. The PD system (10) of any one of claims 1 to 3, wherein the fresh PD fluid inlet (132) comprises a fresh PD fluid inlet (132) with no outlet that receives fresh PD fluid from the patient line (50).

8. The PD system (10) of any one of claims 1 to 3, wherein the patient line (50) is a dual lumen patient line including a fresh PD fluid lumen (52) arranged in fluid communication with a fresh PD fluid port (104f) of the filter set (100), and the dual lumen patient line (50) further includes a spent PD fluid lumen (54) arranged in fluid communication with a spent PD fluid port (104u) of the filter set (100).

9. The PD system (10) of any one of claims 1 to 3, wherein the filter set (100) is configured to connect directly to a patient's transfer set, or the filter set (100) includes flexible tubing (108) configured to connect to the patient's transfer set.

10. The PD system (10) of any one of claims 1 to 3, wherein the PD machine (20) includes a pressure sensor (28b) positioned and arranged to sense the pressure of fresh PD fluid downstream of the filter membrane (112) during patient fill.

11. The PD system (10) of any one of claims 1 to 3, wherein the first and second filter membranes (112a, 112b) are sterilizing grade or bacteria reducing filter membranes.

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