Patent ID: 12196705

DETAILED DESCRIPTION

Various embodiments relate herein to a fluid sensor module configured to connect in-line to a medical device, such as a dialysis treatment system. For example, in kidney hemodialysis systems, blood can be transferred from the patient, through the dialysis treatment system, and back into the patient, to treat the patient's blood. In a peritoneal dialysis (PD) system, the treatment system can pump dialysate in a circulation through the abdominal cavity. During a treatment procedure, it can be important to monitor the composition of constituent materials in a sample fluid such as a treatment fluid (e.g., dialysate) and/or the patient's blood, such as creatinine, potassium, sodium, or any other constituent material that should be monitored. The fluid sensor module can be placed upstream or downstream of the treatment system to monitor the constituent materials.

Beneficially, the fluid sensor module can be sized and configured to be used at home by the patient, or in a clinical setting such as a hospital or clinic. For example, the fluid inlet and outlet can connect to the treatment system by way of a quick connection such as a luer lock or other fluid coupling. The fluid sensor module can mechanically and electrically connect to a reader which can both control the operation of the fluid sensor module and receive and transmit sensing information from the fluid sensor module.

The sensor module can comprise a sensing assembly including a plurality of functionalized electrodes (e.g., twelve electrodes in the illustrated embodiment) that, when exposed to the sample fluid, transmit a signal indicative of a particular constituent component of the sample fluid. A fluid pathway can extend and circulate over the functionalized electrodes to expose the functionalized electrodes to the sample fluid. As shown, the fluid pathway can comprise a curved pathway formed in the housing to convey the sample fluid (and calibration fluid) over the electrodes. The electrodes can electrically connect to corresponding I/O pads.

FIGS.1A-5Kshows one embodiment of a fluid sensor module. The fluid sensor module100shown inFIGS.1A-1Bcan include a lid109enclosing a housing103. The housing103can include a fluid inlet106and a fluid outlet107configured to fluidly connect to a treatment system of the medical device and convey liquid from and back to the treatment system. The module100can include a calibration fluid reservoir105, a plunger108, and a valve102inside the housing103of the fluid sensor module100. A sensing assembly104can be provided at (e.g., attached to) the bottom of the fluid sensor module.

FIGS.2A-2Bshows a top perspective view and a bottom perspective view of the valve102, respectively. The valve120can comprise a valve head120and a valve connector shaft122. The valve connector shaft122can include motor shaft opening126such that the valve connector shaft122is configured to be positioned in a valve seat132of the housing103(seeFIG.3A). The valve120can further include recesses to enable the fluid sensor module100to operate in different positions or modes as discussed below. For example, the valve120can comprise a through recess121, an upper partial recess123, a first lower partial recess124, and a second lower partial recess125.

FIGS.3A-3Bshows additional details of the housing103. The housing103of the fluid sensor module100can have an inlet channel133fluidly connected to the fluid inlet106and an outlet channel134fluidly connected to the fluid outlet107. A fluid can be provided to the valve120through the inlet channel133and out of the valve120through the outlet channel134. A valve seat132can be configured to receive the valve120. A calibration channel135can fluidly connect the valve120to the calibration fluid reservoir105. The housing103can hold the plunger108in the calibration fluid reservoir105as shown inFIG.3B. A sample fluid can be provided to the sensing assembly104by flowing through the fluid pathway130configured to expose the sample fluid to the electrodes140of the sensing assembly104. The sample fluid can enter the fluid pathway130through a sample entry channel136and exit through a sample exit channel137.

FIGS.4A-4Bshows additional details of the sensing assembly104. The sensing assembly104can comprise a plastic mold141with electrodes140embedded in the plastic mold141and exposed to the ambient from one side of the plastic mold141. The sensing assembly104can have I/O pads142exposed to the ambient from the other side of the plastic mold141.

During a treatment procedure, the fluid sensor module can operate in a plurality of modes. As shown inFIGS.5A-5K, a valve can have a plurality of positions configured to place the fluid sensor module in the plurality of modes. The plurality of modes can include a bypass position501, a calibration position502, a sensing position503, and a fill position504. These positions can be enabled by rotating the valve102and aligning the cutouts on the valve102with different channels or cutouts on the housing103. On the valve102, there can be a cutout on valve top surface156(e.g. upper partial recess) and two cutouts on valve bottom surface157(e.g. first and second lower partial recess) as shown inFIG.5A. On the housing103, there can be a cutout on housing158and channels1through5(seeFIG.5A). Channel1can correspond to the inlet channel133; channel2can correspond to the outlet channel134; channel3can correspond to the calibration channel135; channel4can correspond to the sample entry channel136; and channel5can correspond to the sample exit channel137.

For example, in a bypass mode510, the valve102can be placed in the bypass position501. A valve motor disposed in a reader can connect to the valve102of the fluid sensor module100by way of a valve connector (e.g., a valve opening) configured to operably connect to a motor shaft of the valve motor. Processing electronics in the reader can be configured to send instructions to the valve motor to place the fluid sensor module in the bypass mode510by, e.g., rotating the valve102to the bypass position501. In the bypass position501, the channels1and2can be connected to each other allowing a fluid to flow through while the channels3,4,5are blocked by the valve head120(seeFIGS.5A-5C). The through recess121of the valve102can connect channel1(e.g. the inlet channel133) and channel2(e.g., the outlet channel134) as shown inFIG.5C. A sample fluid51(such as the patient's blood, peritoneal dialysate, etc.) can enter a housing of the module by way of a fluid inlet through the channel1and exit the housing through the channel2(seeFIG.5B). In the bypass mode510, the valve can directly connect the fluid inlet to a fluid outlet to convey the sample fluid outside the housing. In the bypass mode510, therefore, the sample fluid (e.g., the patient's blood, peritoneal dialysate, etc.) may not be monitored by the sensor module, but may instead be recirculated to the treatment system.

During a calibration mode520, the valve motor can place the valve102in the calibration position502as shown inFIGS.5A-5B and5D-5E. As shown inFIG.5B, calibration fluid52(also referred to as a quality control fluid, or QC fluid, e.g., a biocompatible fluid such as water, saline, etc.) can be provided in a calibration reservoir105of the housing. In the calibration position502, as in the bypass position501, the sample fluid51can pass directly from the fluid inlet to the fluid outlet to bypass the sensing assembly. That is, channel1(e.g. the inlet channel133) and channel2(e.g. the outlet channel134) can be connected by the through recess121(seeFIG.5D). As shown inFIGS.5A-5B, the valve102can fluidly connect the calibration channel135that is connected to the calibration reservoir105to the sample entry channel136that is in fluid connection with the fluid pathway130and the sensing assembly104. That is, channels3and4can be connected by the upper partial recess123(seeFIG.5D). Finally, in a calibration position502, in some embodiments, the calibration fluid can exit the fluid pathway130and the sensing assembly104by way of a sample exit channel137and the outlet channel134. That is, the channel5and the channel2can be connected by the first lower partial recess124(seeFIG.5D). In some embodiments, the calibration fluid can be entrained with the sample fluid and recirculated into the patient's body. In other embodiments, during calibration, the calibration fluid can be redirected to a separate waste container as shown inFIGS.11and12and discussed further below, which may be disposed of and may not be circulated into the patient's body.

During the calibration mode520, processing electronics of a reader connected to a fluid sensor module can send instructions to a plunger motor of the reader. The plunger motor can rotate the plunger108of the fluid sensor module100by a specified amount to drive a predetermined volume of the calibration fluid from the reservoir105, through the calibration channel135, and into the fluid pathway130to purge the electrodes of the sensing assembly104of sample fluid and any other materials as shown inFIG.5B. The fluid sensor module may be disposable, and the calibration reservoir fluid may be filled in to the reservoir at the factory with a volume sufficient for a preset number of purges, and the plunger rotated about its pivot by the motor through a small angle (e.g., 90°/preset number of purges) for each purge. Thus, in each purge or calibration cycle, the motor can rotate the plunger by a predetermined amount to deliver a predetermined volume of calibration fluid to the sensing assembly. The calibration fluid and the calibration mode can serve to reset the sensor module by flushing the sensing assembly of older sample fluid and/or other debris. Thus, the calibration fluid may also be deemed a purge fluid. The processing electronics can be configured to recognize that the sample fluid is in fluid communication with each of the electrodes.

During a sensing mode530, the valve motor of the reader can rotate the valve102of a fluid sensor module100to the sensing position503as shown inFIGS.5A-5B and5F-5I. In the sensing position503, the sample fluid51can flow through the fluid pathway130and interact with the electrodes140(seeFIG.5B). As shown inFIGS.5A and5F-5G, the channel3(e.g. the calibration channel135) can be blocked by the valve head120and the channel1(e.g. the inlet channel133) and the channel2(e.g. the outlet channel134) can be partially connected by the through recess121such that only a portion of the sample fluid51can exit the module100and the other portion of the sample fluid51can go to the fluid pathway130for sensing. In some embodiments, the through recess can be sized to prevent a bypass of the sample fluid such that substantially all sample fluid is transferred to the fluid pathway. As shown inFIGS.5A and5H-5I, the channel1(e.g. the inlet channel133) and the channel4(e.g. the sample entry channel136) can be fluidly connected by the second lower partial recess125and the channel5(e.g. the sample exit channel137) and the channel2(e.g. the outlet channel134) can be fluidly connected, allowing the sample fluid51to flow into and out of the fluid pathway130as shown inFIG.5B. When the sample fluid51interacts with the electrodes140, in response, the electrodes140can transmit a signal to the I/O pads142of the sensing assembly104and the leads of the reader indicative of respective constituent components of the sample fluid51. The processing electronics of the reader or the computing device in communication with the reader can determine an amount of each constituent component detected by the sensor module. If the amount exceeds or is below a threshold for that component, the processing electronics can be configured to send an alert to the clinician and/or modify the treatment procedure (e.g., shut off the procedure, change the parameters of the procedure, etc.).

The processing electronics of the reader can be programmed to automatically switch between various modes of the fluid sensor module. For example, the process electronics can be programmed to automatically cycle between the sensing mode (in which the constituent component(s) of the sample fluid are monitored) and the calibration mode (in which the calibration fluid flushes the sensing assembly). In some embodiments, the processing electronics can be further configured to automatically switch into the bypass mode when the sensing device is to be inactive. In some embodiments, the user (e.g., patient or clinician) can manually switch modes by engaging a user interface (UI) of the reader. The UI of the reader can comprise a touch screen and/or buttons that enable the user and/or clinician to interact with the reader. In some embodiments, the UI can include a display that indicates the levels of the constituent fluids.

In addition, the sensor module can include a fill mode540by rotating the valve102to a fill position504(seeFIGS.5J and5K). In the fill mode540, the calibration fluid52can be pumped or otherwise driven into the fluid inlet106. In some embodiments, as shown inFIG.5B, the plunger108can be rotated/moved (e.g. manually or by the motor of the reader) to drive the calibration fluid52to transfer from the fluid inlet106to the calibration reservoir105by way of the calibration channel135. Thus, in the fill mode540, the calibration fluid52can travel in a reverse direction along the calibration channel135as compared to during the calibration mode520. As shown inFIG.5A, channel1(e.g. inlet channel133) and channel3(e.g. calibration channel135) can be fluidly connected by the through recess121and channel2, channel4, and channel5can be blocked. In various embodiments, the calibration reservoir can be filled prior to use, e.g., in the factory or assembly plant.

FIGS.6A-6Cshows another embodiment of a fluid sensor module in an assembly with a reader. The assembly can include a reader160, a fluid sensor module100acomprising a fluid inlet106aand a fluid outlet107a. The reader160can comprise a plunger motor (not shown) connectable to a plunger108ain the housing103athrough a first motor shaft161on the reader160and a corresponding plunger motor connector165aon the sensor module100a. The reader160can further comprise a valve motor (not shown) connectable to a valve102ain the housing103aof the sensor module100athrough a second motor shaft162on the reader160and a corresponding plunger motor connector164aon the sensor module100a. Leads163of the reader160can electrically connect to corresponding I/O pads142aof the sensor module100a. In some embodiments, the reader can comprise processing electronics configured to control the operation of the valve motor and the plunger motor. The processing electronics can also be configured to store and/or process signals transduced by the sensor module and transferred to the leads by way of the I/O pads. In various embodiments, the processing electronics can be configured to identify a constituent composition of the sample fluid. The reader can communicate with a computing device, such as a central server, a mobile device (e.g., a smartphone), a laptop computer, or the like to convey the sensed data to the clinician. For example, the reader can wirelessly transmit the data to the computing device. In other embodiments, the reader can be electrically connected to the computing device by an electrical connector, such as a cable or cord.

FIGS.7-10shows another embodiment of a fluid sensor module200. As shown inFIGS.7A and7B, the fluid sensor module200can have a housing203and a lid209enclosing a valve202, a plunger208, and a calibration fluid reservoir205. A sensing assembly204can be embedded in the housing203. The housing203can have a fluid inlet206and a fluid outlet207. As shown inFIGS.8A-8B, the valve202can have seals180(e.g. O-rings) positioned above and below the valve head220. As shown in-FIG.9FIGS.9A-9E, the sensing assembly204can include pre-formed lead frame244configured inside a plastic mold241. Electrodes240can be positioned on top of the sensing assembly204and I/O pads242can be positioned on bottom of the sensing assembly204. Adhesive243can be applied to the plastic mold241to fix the sensing assembly204to the housing203.FIG.10shows-FIGS.10A and10Bshow the plunger208that can comprise a body228and an outer layer218wrapped around sides of the body228.

FIGS.11A,11B,12A, and12Bshow additional embodiments of the fluid sensor module. In some embodiments, a waste container310can be positioned above a calibration reservoir312for a fluid sensor module300as shown inFIGS.11A and11B. Instead of transferring the used calibration fluid through the outlet and into the medical treatment system and/or patient, the used calibration fluid can alternatively be routed upwardly by way of an internal channel (not shown) to the waste container310. A partition311can separate the used calibration fluid in the waste container310from the fresh calibration fluid in the calibration fluid reservoir312. InFIGS.11A and11B, the positioning of the waste container above the calibration fluid reservoir can utilize vertical space above the reservoir to preserve lateral footprint. In some embodiments, a fluid sensor module400can include a waste container410positioned laterally adjacent a calibration reservoir412, as shown inFIGS.12A and12B. Instead of transferring the used calibration fluid through the outlet and into the medical treatment system and/or patient, the used calibration fluid can alternatively be routed laterally by way of an internal channel (not shown) to the waste container410. A partition411can separate the used calibration fluid in the waste container410from the fresh calibration fluid in the calibration fluid reservoir412. InFIGS.12A and12B, the positioning of the waste container410laterally adjacent the calibration fluid reservoir412can utilize lateral space to vertical height. Additional designs for a waste container may be suitable so as to provide a desired lateral footprint and/or vertical height.

Beneficially, the fluid system disclosed herein can enable the patient to conduct medical treatments (such as dialysis) at home, or otherwise outside of a clinical setting. As one example, when the patient goes to bed for the night, the patient can initiate the dialysis system, and connect the fluid sensor module to the reader. The fluid inlet and fluid outlet of the fluid sensor module can fluidly connect to the treatment system of the medical device, for example, by way of a luer lock or other fluid coupler. The dialysis (or other) machine can be activated, and the sensor module can automatically cycle between bypass mode, calibration mode, and sensing mode (in any suitable order). If an anomaly is detected during the sensing mode, the reader can transmit an alarm to the clinician and/or otherwise modify the treatment procedure automatically. Once the treatment procedure is completed, the patient can disengage the treatment system, and remove the fluid sensor module. The fluid sensor module can be disposed and, for the next treatment procedure, a new fluid sensor module can be inserted into the reader and connected to the medical device.

Although the devices and methods were described to be used with medical treatment and in medical settings, it is to be appreciated that the procedures and devices disclosed herein may be performed on or applied to any kinds of sample or fluid to be tested or sensed with sensors.

Unless the context clearly requires otherwise, throughout the description and the claims, the words “comprise,” “comprising,” “include,” “including” and the like are to be construed in an inclusive sense, as opposed to an exclusive or exhaustive sense; that is to say, in the sense of “including, but not limited to.” The word “coupled”, as generally used herein, refers to two or more elements that may be either directly connected, or connected by way of one or more intermediate elements. Likewise, the word “connected”, as generally used herein, refers to two or more elements that may be either directly connected, or connected by way of one or more intermediate elements. Additionally, the words “herein,” “above,” “below,” and words of similar import, when used in this application, shall refer to this application as a whole and not to any particular portions of this application. Moreover, as used herein, when a first element is described as being “on” or “over” a second element, the first element may be directly on or over the second element, such that the first and second elements directly contact, or the first element may be indirectly on or over the second element such that one or more elements intervene between the first and second elements. Where the context permits, words in the above Detailed Description using the singular or plural number may also include the plural or singular number respectively. The word “or” in reference to a list of two or more items, that word covers all of the following interpretations of the word: any of the items in the list, all of the items in the list, and any combination of the items in the list.

Moreover, conditional language used herein, such as, among others, “can,” “could,” “might,” “may,” “e.g.,” “for example,” “such as” and the like, unless specifically stated otherwise, or otherwise understood within the context as used, is generally intended to convey that certain embodiments include, while other embodiments do not include, certain features, elements and/or states. Thus, such conditional language is not generally intended to imply that features, elements and/or states are in any way required for one or more embodiments.

While certain embodiments have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the disclosure. Indeed, the novel apparatus, methods, and systems described herein may be embodied in a variety of other forms; furthermore, various omissions, substitutions and changes in the form of the methods and systems described herein may be made without departing from the spirit of the disclosure. For example, while blocks are presented in a given arrangement, alternative embodiments may perform similar functionalities with different components and/or circuit topologies, and some blocks may be deleted, moved, added, subdivided, combined, and/or modified. Each of these blocks may be implemented in a variety of different ways. Any suitable combination of the elements and acts of the various embodiments described above can be combined to provide further embodiments. The accompanying claims and their equivalents are intended to cover such forms or modifications as would fall within the scope and spirit of the disclosure.