Devices for dermal interstitial fluid monitoring and related methods

Abstract

A device for measuring interstitial fluid (ISF) properties of a patient includes: a therapeutic unit configured to contact on a patient's skin, the unit having a skin-facing surface; a microneedle-based analyte sensor mounted on the skin-facing surface, the microneedle-based analyte sensor configured to collect information regarding at least one component of chemistry of the patient; and a processor operatively connected with the microneedle-based analyte sensor to receive signals from the microneedle-based analyte sensor and transmit information to a remote analysis system.

Description

DEVICES FOR DERMAL INTERSTITIAL FLUID MONITORING AND RELATED METHODSRelated Application

[0001] The present application claims priority from, and the benefit of, Indian Patent Application No. 202441019498, filed March 16, 2024, the disclosure of which is hereby incorporated herein by reference in full.Field

[0002] The present invention relates to medical devices, and in particular, devices for dermal interstitial fluid monitoring.Background

[0003] Catheters are medical devices that can be inserted in the body to treat diseases or perform a surgical procedure. Catheters are manufactured for specific applications, such as cardiovascular, urological, gastrointestinal, neurovascular and ophthalmic procedures. In most uses, a catheter is a thin, flexible tube (soft catheter) though catheters are available in varying levels of stiffness depending on the application. Catheters can be inserted into a body cavity, duct, vessel, brain, skin or adipose tissue. Functionally, they allow drainage, administration of fluids or gases, access by surgical instruments, and also perform a wide variety of other tasks depending on the type of catheter.

[0004] When a catheter is left in place in a patient long-term, a secondary securement may be used to secure the catheter to the body. Solutions to secure the catheter include sutures and catheter securement devices (an exemplary catheter securement device is the STATLOCK™ device, the BD NEXIVA™ closed IV catheter system device or the GUARDIVA® device, each available from Becton, Dickinson and Company of Franklin Lakes, N.J.). The securements are often attached to the skin of a body into which the catheter will be inserted.

[0005] It may be desirable to provide techniques for improving the functionality of the securement, which may in turn improve patient outcomes.Summary

[0006] As a first aspect, embodiments of the invention are directed to a device for measuring interstitial fluid (ISF) properties of a patient. The device comprises: a therapeutic unit configured to contact on a patient’s skin, the unit having a skin-facing surface; a microneedle-based analyte sensor mounted on the skin-facing surface, the microneedle-based analyte sensor configured to collect information regarding at least one component of chemistry of the patient; and_a processor operatively connected with the microneedle-based analyte sensor to receive signals from the microneedle-based analyte sensor and transmit information to a remote analysis system.

[0007] As a second aspect, embodiments of the invention are directed to a device for measuring interstitial fluid (ISF) properties of a patient comprising: a unit configured to mount on a patient’s skin adjacent a site for an intravenous catheter, the unit designed to participate in the securement and / or care of the intravenous catheter, the unit having a skin-facing surface; a microneedle-based analyte sensor mounted on the skin-facing surface, the microneedle-based analyte sensor configured to collect information regarding at least one component of chemistry of the patient; and a processor operatively connected with the microneedle-based analyte sensor to receive signals from the microneedle-based analyte sensor and transmit information to a remote analysis system.

[0008] As a third aspect, embodiments of the invention are directed to a device for measuring interstitial fluid (ISF) properties of a patient comprising: a wearable unit configured to be worn by a patient, the wearable unit having a skin-facing surface; a microneedle-based analyte sensor mounted on the skin-facing surface, the microneedle-based analyte sensor configured to collect information regarding at least one component of chemistry of the patient; and_a processor operatively connected with the microneedle-based analyte sensor to receive signals from the microneedle-based analyte sensor and transmit information to a remote analysis system.Brief Description of the Drawings

[0009] FIGS. 1 A-1E are perspective, bottom inset (2), exploded and side views of an exemplary primary securement device with microneedle-based multi-analyte sensor.

[0010] FIG. 2 is a schematic diagram of an exemplary system architecture diagram for a securement device with microneedle ISF monitoring.

[0011] FIG. 3 is a schematic diagram of exemplary circuitry for a securement device with microneedle ISF monitoring.

[0012] FIG. 4 is a schematic diagram of exemplary circuitry for signal conditioning that may be included in a securement device such as that shown in FIG. 3.

[0013] FIGS. 5A and 5B are perspective views of microneedle arrangement layouts for ISF analyte monitoring a diagram showing alternative arrangements.

[0014] FIGS. 6A and 6B are top and bottom partially exploded perspective views, respectively, of another example of a securement device including ISF monitoring.

[0015] FIGS. 7A and 7B are top and bottom partially exploded perspective views, respectively, of another example of a securement device including ISF monitoring.

[0016] FIGS. 8A-8C are top, bottom and exploded perspective views of an implementation of the features in an IV site protection device, such as a BD GUARDIVA® device, according to embodiments of the invention.

[0017] FIGS. 9A and 9B are exploded and assembled bottom perspective views of an implementation of the features in a closed IV catheter configuration, such as integrated into a BD NEXIVA™ closed IV catheter system device, according to embodiments of the invention.

[0018] FIGS. 10A and 10B are exploded and environmental views of a standalone sensing patch configuration according to embodiments of the invention.

[0019] FIGS. 11A and 11B are front and rear perspective views of a wearable device configuration according to embodiments of the invention.Detailed Description

[0020] It is noted that aspects of the invention described with respect to one embodiment, may be incorporated in a different embodiment although not specifically described relative thereto. That is, all embodiments and / or features of any embodiment can be combined in any way and / or combination. Applicant reserves the right to change any originally filed claim and / or file any new claim, accordingly, including the right to be able to amend any originally filed claim to depend from and / or incorporate any feature of any other claim or claims although not originally claimed in that manner. These and other objects and / or aspects of the present invention are explained in detail in the specification set forth below. Further features, advantages and details of the present invention will be appreciated by those of ordinary skill in the art from a reading of the figures and the detailed description of the preferred embodiments that follow, such description being merely illustrative of the present invention.

[0021] There is a strong need to reduce time to decision for critical medication titration while leveraging existing clinical practices to introduce continuous monitoring. Healthcare professionals need a technology that can measure (in vivo) up to 11 vitals (like basic metabolic panel analytes) in real time from interstitial fluid and communicate this data to the electronic medical records.

[0022] Current solutions are suboptimal. The scope of improvement (pain-points) with currently available modalities for disease biomarker analysis include: (1) labor shortages, resulting in more pokes and delay in timely data and costly training; (2) lack of continuous analyte data, meaning the feedback during treatment is not as fast as it could be, resulting in longer stay at higher acuity settings; (3) lack of continuous analyte data, meaning value that is not known to science (i.e., new telemetry) cannot be achieved; (4) limitations associated with blood draw measurements such as: (i) pain caused by venipuncture and lancets, (ii) needle phobia to patient, (iii) possible delayed skin healing, (iv) generation of biohazardous sharp waste, (v) possibility of needle-stick injuries to healthcare professionals, (vi) increased risk of infection as blood sampling is prone to biofouling or chance of cross-contamination if the device is used on more than one person, (vii) the need for trained healthcare professionals for aspiration, (viii) need of capital equipment for postprocessing of collected blood (e.g., separation of blood plasma from whole blood), and (ix) blood is prone to clotting due to presence of clotting factors, which makes continuous monitoring of blood analytes difficult; (5) currently available basic metabolic panel analytes measurement point- of-care devices lack continuous measurement potential and need dedicated readout / blood processing device and are capillary blood draw-dependent; and (6) some of the latest continuous interstitial fluid (ISF) glucose or lactate monitoring wearable devices using microneedles such as those from from Biolinq, K’Watch, Sano / One Drop along with commercial continuous glucose monitoring devices such as those from Abbott, Medtronic, or Dexcom lack multiplexability. These devices are mono-analyte biosensor devices purpose-built for sensing but not tailored to take advantage of medical protocols and / or workflows and devices employed therein.

[0023] Innovative features are now described more fully hereinafter with reference to the accompanying drawings, in which embodiments of the invention are shown. The features may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the innovative features to those skilled in the art.

[0024] In the figures, certain layers, components, or features may be exaggerated for clarity, and broken lines illustrate optional features or operations unless specified otherwise. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

[0025] It will be understood that, although the terms first, second, etc. may be used herein to describe various elements, components, regions, layers and / or sections, these elements, components, regions, layers and / or sections should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer or section from another region, layer, or section. Thus, a first element, component, region, layer, or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the present invention. The sequence of operations (or steps) is not limited to the order presented in the claims or figures unless specifically indicated otherwise.

[0026] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the specification and relevant art and should not be interpreted in an idealized or overly formal sense unless expressly so defined herein. Well-known functions or constructions may not be described in detail for brevity and / or clarity.

[0027] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and / or "comprising", when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0028] As used herein, phrases such as "between X and Y" and "between about X and Y" should be interpreted to include X and Y. As used herein, phrases such as "between about X and Y" mean"between about X and about Y." As used herein, phrases such as "from about X to Y" mean "from about X to about Y. "

[0029] It will be understood that when an element is referred to as being "on", "attached" to, "connected" to, "coupled" with, "contacting", etc., another element, it can be directly on, attached to, connected to, coupled with or contacting the other element or intervening elements may also be present. In contrast, when an element is referred to as being, for example, "directly on", "directly attached" to, "directly connected" to, "directly coupled" with or "directly contacting" another element, there are no intervening elements present. It will also be appreciated by those of skill in the art that references to a structure or feature that is disposed "adjacent" another feature may have portions that overlap or underlie the adjacent feature.

[0030] Spatially relative terms, such as "under", "below", "lower", "over", "upper", "lateral", "left", "right" and the like, may be used herein for ease of description to describe one element or feature’s relationship to another element(s) or feature(s) as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is inverted, elements described as "under" or "beneath" other elements or features would then be oriented "over" the other elements or features. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the descriptors of relative spatial relationships used herein interpreted accordingly.

[0031] Some embodiments of the present invention are directed to medical devices (e.g., , such as catheter securement solutions) that include multiplexed interstitial fluid analyte monitoring capability in addition to serving other functions in a medical treatment. The embodiments shown in FIGS. 1A - 11B illustrate devices that integrate medical devices with ISF monitoring. For example, FIGS. 1A-1E illustrate a device, designated broadly at 100, that combines a catheter securement unit 102 with a microneedle-based multi-analyte sensor array 104. As shown in FIGS. 1A, ID and IE, the catheter securement unit 102 includes a generally planar main body 103 with a lower surface 105 and catheter securement members 106 that are mounted to the upper surface 107 of the main body 103. The catheter securement unit 102 is configured to be adhered to the skin of a patent via an adhesive or the like applied to the lower surface 105 of the main body 103. The catheter securement members 106 are configured to receive and secure a component of a catheter (e.g., a catheter hub, such as that shown at H in FIG. 6A). The catheter securement unit102 is typically positioned adjacent to a catheter insertion site to maintain the catheter in place. As mentioned above, an exemplary catheter securement unit is a STATLOCK® device, available from Becton, Dickinson and Company (Franklin Lakes, New Jersey).

[0032] Referring still to FIGS. 1A-1E, the microneedle-based multi-analyte sensor array 104 is mounted on the lower surface 105 of the main body 103. As can be seen in FIG. ID, the sensor array 104 incudes a microneedle patch 116 with a plurality of downwardly-extending microneedles 110 arranged on a grid of rows and columns. The sensor array 104 also includes a printed circuit board (PCB) chip 114 on which the microneedle patch 116 is mounted. A battery 112 is positioned above the PCB chip 114 to provide power to the sensor array 104 (FIG. ID). A cover 118 that protects the microneedles 110 until use underlies the other components of the sensor array 104.

[0033] The microneedles 110 of the microneedle patch 116 provide access of the body ISF to the sensor array 104. Different sections of the arrays of microneedles 110 are functionalized with different analytes to follow the respective chemistry at the active layer of the respective microneedle(s) surrounded by the ISF. As a result, the microneedles 110 can provide an electric signal output (i.e., they act as electrodes) which is addressed separately for the respective microneedle(s) and transmitted wirelessly / through wired connection to a remote display / data recording and / or analysis system. Three features shown in FIG. 1 that contribute to the improved monitoring device are the microneedle array, the integration of enzymes-mediated and ion selective membrane-based electrochemical sensing, and specialized electronics.

[0034] The array(s) of microneedles 110 may be arranged in an optimized pattern. The form factor of the proposed microneedle platform, such as are shown in FIGS. IB and 1C, can enable: multiplexing the electrochemical sensing device for multiple modalities because of the size and location of each microneedle on the device; and reduced pain while inserting or affixing the secondary securement and during the period of monitoring. In some embodiments, the microneedle design may be miniaturized enough to fit multiple microneedles and / or arrays on the device 100 (or for implementing as an independent wearable patch as described below).

[0035] With regard to the integration of enzyme-mediated and ion selective membrane-based electrochemical sensing, current sensing technologies typically implement only one of the sensing modalities. The proposed features and configurations described herein facilitate integration of both of these technologies together for making a biosensor device to measure a significantly more usefulensemble of biomarkers, like (but not limited to) glucose, lactate, sodium, and potassium, using a single device.

[0036] With reference to the electronics (which are largely included on the PCB chip 114, which serves as a controller or processor for receiving signals from the microneedles 110 and transmitting them to a remote analysis system as is discussed in connection with FIGS. 2-4), the proposed features include aspects to power the sensor action as well as for transmission of signal output. Some implementations may include an integrated battery / power harvesting device (e.g., the battery 112) to ensure the supply of bias voltage / current for potentiometric / amperometric measurement by the sensing elements and the transmission of current / voltage signal to the remote display / data recording and / or analysis system.

[0037] FIG. 2 shows an example system architecture diagram for the device 100. The system shown in FIG. 2 may be implemented on a single securement device 100. While three separate microneedle patches 116 are shown in FIG. 2, the patches 116 may be affixed to the same securement device 100 to monitor the same patient. Each microneedle patch 116 may include three different types of microneedle electrodes: working electrodes 110a; reference electrodes 110b; and counter electrodes 110c. Potential arrangements of these electrode types are shown in FIGS. IB, 1C, 5A and 5B. Each of the microneedle patches 116 is connected with a common data acquisition system 150, which is in turn connected with a data processing system 160. The data acquisition system 150 may cause the microneedle patch to transmit analyte data such as through an interrogation signal or NFC powered messaging. The data processing system 160 may format or otherwise process the information received from the data acquisition system 150. In some implementations this may include augmenting the information to identify the device 100, patient, or other information related to the sensor 104 or device 100. A communication module 180 may be included to communicate with an external device such as a smartphone, network, or other device. The communication module 180 may be used to acquire power for the system such as through NFC power harvesting, inductive power, or similar wireless power conveyances. Any or all of the components discussed above (i.e., the data acquisition system 150, the data processing system 160, and the communication module 180) may be considered generally as a “processor” as the term is used herein.

[0038] In some implementations, a display module 170 may be included to provide a human- perceivable indication based on the analyte information. For example, the display module 170 mayinclude a light that can be activated by the data processing system 160 when a measurement for an analyte level exceeds a threshold value, which may alert a technician to examine and potentially address the patient’s condition. The display module 170 may additionally or alternatively provide status information for the system such as: power status, communication status, status of a microneedle patch, or the like.

[0039] FIG. 3 shows a diagram of example circuitry for the device 100 which may be found on the PCB chip 114. Each sensor 116-1 to 116-N is connected with a signal conditioning unit 200, which includes an amplifier 202 and a filter 204 for each sensor array 104 to amplify signals and suppress noise. FIG. 3 also shows a second signal conditioning unit 206 that is connected with the signal conditioning unit 200. The signal conditioning unit 206 (also shown in FIG. 4) can convert the analog signals transmitted from the signal conditioning unit 200 to digital signals. FIG. 3 also shows a transmission module 208 and a user interface 210, which can enable a user to read and respond to the information gathered from the sensors 116 of the sensor arrays 104. FIG. 4 shows a diagram of example circuitry for the signal conditioning units 200, 206 that may be included in a securement device such as that shown in FIG. 3.

[0040] FIGS. 5 A and 5B show diagrams of microneedle arrangement layouts for ISF analyte monitoring. The layout and arrangement of microneedle electrodes 110 in electrochemical biosensors can be optimized based on one or more of: size of the securement device, types of analytes to be detected, and number of different analytes to be detected. Microneedles 110 can be arranged in different formats by optimizing relative distance between working electrode(s) 110a, reference electrode(s) 110b, and counter electrode(s) 110c. A single microneedle patch 116 for sensing a particular analyte may include these three independent elements (electrically insulated) for measurement. Multiple patches 116 may be included on a single securement device 100.

[0041] The form of the microneedles 110 can take into account three factors: resistance to skin penetration, target fluid to monitor, and patient discomfort. Balancing these factors can impact the sensitivity such that a more analyte-sensitive microneedle may cause more patient discomfort. As such, experimental data has identified some preferred tolerances for the form factor of the microneedle array. In one implementation, microneedle length of 400-600pm was found to be sufficient. Microneedles of lengths shorter than 300pm can cause folding of skin around microneedle arrays, either preventing penetration or allowing for suboptimal penetration. Microneedles with a length below 600pm are sufficient for dermal ISF monitoring. Painexperienced by the patient depends primarily on the force of microneedle tip insertion (tip diameter) and the depth to which the microneedle tip penetrates the skin (MN length). The effect of microneedle design on discomfort in humans showed that microneedles less than or equal to 500 pm in length resulted in significantly less discomfort than those with length greater than 700 pm. A tip angle of less than or equal to 20 degrees was found to strike a desirable balance between discomfort and resistance for the microneedles. A tip diameter between 1 and 15 pm was found to provide adequate penetration to monitor the widest range of analytes while minimizing discomfort. The shapes of the microneedle that provided the most desirable outcomes were a pyramidal or tapered cone cylindrical shape. These shapes proved optimal for relatively low skin insertion force compatible with catheter securement devices. The geometry of the base that was square (e.g., 4 vertices) with a diameter of between 200 and 300 pm provided a desirable array arrangement and the associated circuit wiring space. The pitch / interspacing between microneedles that provided the optimal results depended on the target microneedle. If the microneedle was polymeric, 1500 to 2500 pm of interspacing was sufficient. If the microneedle was silicon or metal, there was no significant effect of interspacing size and a range of possible sizes to accommodate securement designs (e.g., standard, adult, neonatal, etc.) can be implemented.

[0042] The proposed features can provide several non-limiting advantages over existing devices. One non-limiting advantage is the integration with a securement device that is already needed on a patient. The feature integrates ISF monitoring into devices used in critical care or other healthcare settings without substantial change in current form-factor while retaining existing functionalities along with the enhanced monitoring capabilities. A second non-limiting advantage is to continuously measure a required set of analytes (disease biomarkers) through interstitial fluid with minimal pain using microneedles. A third non-limiting advantage is the unique multiplexed biosensor which provides simultaneous measurement of disease biomarker analytes, for example but not limited to, metabolites like glucose and lactate and electrolytes like sodium and potassium through single device. A fourth non-limiting advantage of the described features is providing a feedback-based closed-loop system for medication delivery. For example, as the catheter is secured to a patient to deliver a potentially lifesaving therapy, the same device can monitor and provide feedback on the status of the patient to allow automated adjustments to the therapy based on the feedback.

[0043] FIGS. 6 A and 6B show top and bottom perspective views, respectively, of another example of the device 100 without the cover 118.

[0044] FIGS. 7A and 7B show top and bottom views, respectively, of another example of a device including ISF monitoring designated broadly at 100’. The device 100’ shown in FIGS. 7A and 7B includes a microfluidic assembly 117 between the PCB chip 114’ and the microneedle patch 116’ to provide additional monitoring features. One or more microfluidic channels may be provided to draw and analyze fluids from the patient.

[0045] While the examples thus far have focused on catheter secondary securement devices, such as the BD StatLock® securement device, the features may be implemented in other IV-related securement devices. FIG. 8 shows implementation of the features in an IV site protection device 300, such as a BD GUARDIVA® device. The device 300 includes microneedle patches 316, a PCB 314, and a battery 312 that function similarly to the analogous components described above. The device 300 also includes an adhesive layer 322 to attach the microneedle patches 316 to the PCB, and a top casing 324. Gathering of ISF information from the device 300 is similar to that of the devices 100, 100’; as the device 300 is in place at an IV insertion site, ISF information can be collected and analyzed in the manner described above.

[0046] FIGS. 9A and 9B illustrate a device 400, which includes a microneedle-based sensor array 404 mounted on a closed IV catheter device 402 (such as a Becton, Dickinson and Company NEXIVA® device). In this implementation, the microneedle patches 416 are mounted on the underside of the wings 405 of the catheter device 402. In some instances, the sensor arrays 404 may be molded into the device 402 during its manufacturing. As such, when the device is deployed with a catheter, ISF information can be gathered with the arrays 404.

[0047] Those of skill in this art will appreciate that microneedle-based sensor arrays can be used with other types of medical devices, including wearable devices. FIGS. 10A and 10B show a standalone sensing patch 500 that includes a microneedle patch 516, an adhesive pad 522, a PCB chip 514, a battery 512, and a top casing 526. As shown in FIG. 10B, the patch can be worn by a user and transmit ISF information wirelessly to an external device. As another example, FIG. 11 shows a wearable device 600 styled as a watch, bracelet, anklet, arm band or collar, with a body 602 having a microneedle-based sensor array 604 on its underside. The body 602 is held on the user’s arm with a strap 606. ISF information can be gathered via the sensor array 604. Electronics for processing and displaying the information can be housed within the body 602.

[0048] Those of skill in this art will appreciate that devices other than those shown herein may be suitable for providing measurement of ISF via microneedle-based analyte collection and analysis as well as providing another medical function while in contact with a patient’s skin. Examples include specialized dressings, ventilation tubes, support devices such as splints, casts and braces, catheters (e.g., IV catheters, arterial catheters, etc.), healthcare wearable devices, on- demand drug delivery devices (e.g., insulin pumps), and other therapeutic units. Other possibilities may exist also.

[0049] The foregoing is illustrative of the present invention and is not to be construed as limiting thereof. Although a few exemplary embodiments of this invention have been described, those skilled in the art will readily appreciate that many modifications are possible in the exemplary embodiments without materially departing from the novel teachings and advantages of this invention. Accordingly, all such modifications are intended to be included within the scope of this invention as defined in the claims. The invention is defined by the following claims, with equivalents of the claims to be included therein.

Claims

We Claim:

1. A device for measuring interstitial fluid (ISF) properties of a patient, comprising: a therapeutic unit configured to contact on a patient’s skin, the unit having a skin-facing surface; a microneedle-based analyte sensor mounted on the skin-facing surface, the microneedlebased analyte sensor configured to collect information regarding at least one component of chemistry of the patient; and a processor operatively connected with the microneedle-based analyte sensor to receive signals from the microneedle-based analyte sensor and transmit information to a remote analysis system.

2. The device defined in Claim 1, wherein the unit comprises an intravenous site protection device.

3. The device defined in Claim 1, wherein the unit comprises a wearable unit.

4. The device defined in Claim 1, wherein the microneedle-based analyte sensor is configured to detect the presence of at least one of glucose, lactate, sodium, and potassium,5. The device defined in Claim 1, wherein the unit is configured to detect a plurality of components of chemistry of the patient.

6. The device defined in Claim 1, wherein the processor is operatively connected with a display device.

7. The device defined in Claim 1, wherein the microneedle-based sensor includes at least one working electrode, at least one counter electrode, and at least one reference electrode.

8. The device defined in Claim 1, wherein the microneedle-based analyte sensor includes a plurality of microneedles.

9. The device defined in Claim 8, wherein the plurality of microneedles have a length of between about 400 and 600 pm.

10. The device defined in Claim 8, wherein the plurality of microneedles have a tip diameter of between about 1 and 15 pm.

11. The device defined in Claim 8, wherein the plurality of microneedles have a tip shape that is pyramidal or conic.

12. A device for measuring interstitial fluid (ISF) properties of a patient, comprising: a unit configured to mount on a patient’s skin adjacent a site for an intravenous catheter, the unit designed to participate in the securement and / or care of the intravenous catheter, the unit having a skin-facing surface; a microneedle-based analyte sensor mounted on the skin-facing surface, the microneedlebased analyte sensor configured to collect information regarding at least one component of chemistry of the patient; and a processor operatively connected with the microneedle-based analyte sensor to receive signals from the microneedle-based analyte sensor and transmit information to a remote analysis system.

13. The device defined in Claim 12, wherein the unit comprises a catheter securement unit.

14. The device defined in Claim 12, wherein the unit comprises an intravenous site protection device.

15. The device defined in Claim 12, wherein the microneedle-based analyte sensor is configured to detect the presence of at least one of glucose, lactate, sodium, and potassium.

16. The device defined in Claim 12, wherein the unit is configured to detect a plurality of components of chemistry of the patient.

17. The device defined in Claim 12, wherein the microneedle-based sensor includes a microneedle patch, a printed circuit board that overlies the patch, and a power source operatively connected with the printed circuit board and with the processor.

18. The device defined in Claim 17, wherein the sensor further comprises a multifluidic panel between the patch and the printed circuit board.

19. The device defined in Claim 12, wherein the processor is operatively connected with a display device.

20. The device defined in Claim 12, wherein the microneedle-based sensor includes at least one working electrode, at least one counter electrode, and at least one reference electrode.

21. A device for measuring interstitial fluid (ISF) properties of a patient, comprising: a wearable unit configured to be worn by a patient, the wearable unit having a skin-facing surface; a microneedle-based analyte sensor mounted on the skin-facing surface, the microneedlebased analyte sensor configured to collect information regarding at least one component of chemistry of the patient; and a processor operatively connected with the microneedle-based analyte sensor to receive signals from the microneedle-based analyte sensor and transmit information to a remote analysis system.

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