The present disclosure generally relates to a pump system for infusing a patient with a fluid, for example, a pump arranged within a wearable medicament delivery system, and, in particular, a pump system configured to determine pump cycle or sequencing information.
Healthcare providers may prescribe patients wearable devices for delivering fluids, such as liquid medicaments, as part of a treatment regimen. Non-limiting examples of medicaments may include chemotherapy drugs, hormones (for instance, insulin), pain relief medications, and other types of liquid-based drugs. In general, wearable medicament delivery devices are relatively small form factors that may be adhered to the skin of the patient, with a reservoir to hold the medicament. The device may include a needle or cannula fluidically coupled to the reservoir and extending from the device and into the skin of the patient. A pump may operate to force the fluid from the reservoir, through a fluid path, and out through the needle and into the patient. A control system, with hardware and/or software elements, may be arranged within the device to manage medicament delivery and other device features. The control system may operate alone or in combination with an external computing device, such as a patient smartphone, healthcare provider computer, and/or the like. Minimizing the footprint of a wearable medicament delivery device makes the device less obtrusive to the patient and improves the overall user experience. Accordingly, the dimensions of operational devices, such as fluid pumps, are kept as small as possible.
Determining operational information for a wearable medicament delivery device and individual components is key to maintaining proper functioning and ensuring patient safety during use. However, smaller component sizes and footprint constraints make it more challenging to sense component status information. For example, the pump chamber volume is typically much smaller than the device's fluid reservoir volume and is therefore refilled periodically. A pump may use various mechanisms to initiate a refill process to refill the pump chamber with a fluid. Before this refill process occurs, the exit port to the patient must be closed and the entry port to the reservoir must be opened. With conventional pump systems that are dimensioned for a wearable medicament delivery device, it is challenging to efficiently and accurately determine when the fill process is going to occur with sufficient time so that the switch can happen, particularly if there is an error.
Therefore, there is a need for an improved pumping mechanism for a wearable medicament delivery device that can accurately and efficiently determine status information for device components, such as a fluid pump.
The drawings are not necessarily to scale. The drawings are merely representations, not intended to portray specific parameters of the disclosure. The drawings are intended to depict example embodiments of the disclosure, and therefore should not be considered as limiting in scope. In the drawings, like numbering represents like elements
The described technology generally relates to a wearable fluid delivery device for delivering a fluid to a patient. In some embodiments, the fluid may be or may include a medicament. The wearable fluid delivery device may include a reservoir for holding the fluid, a fluid path in fluid communication with the reservoir, a needle in fluid communication with the fluid path to deliver the fluid to the patient wearing the wearable fluid delivery device, and a fluid delivery pump configured to force the fluid from the reservoir, through the fluid delivery path, and into the patient via the needle.
In some embodiments, a fluid pump may include a pump location determination assembly or pump status assembly configured to determine a step, process, sequence, state, component location, component orientation, or other operational information of a fluid delivery pump. In various embodiments, the pump status assembly may operate to determine status or location information (for instance, where a rotating member is in a rotation cycle) for one or more components of the fluid pump. Accordingly, wearable fluid delivery device control components may use the status information to monitor device operations and/or perform functions based on the status information.
For example, in some embodiments, a fluid pump may be or may include a reciprocating pump (see, for example,
Accordingly, in some embodiments, a pump status assembly may include electronic sensors that provide the ability to recognize where one or more pump components, such as a piston, ratchet wheel, and/or other components are located in a pump cycle. For example, the pump status assembly may determine where a pump piston and/or ratchet wheel are with respect to the snail cam and, more importantly, with respect to a snail cam drop-off. Therefore, in some embodiments, a pump status assembly may provide a feedback system that will allow a fluid pump (or device control elements) to recognize when the snail cam drop-off is approaching and switch the pump from the patient to the reservoir accordingly.
In some embodiments, a pump status assembly may be configured to determine operational information associated with a fluid pump. In various embodiments, the pump status assembly may operate to determine a position, location, orientation, state, and/or other status of a pump element. The pump status assembly may include a first electrical element configured to engage a second electrical element to indicate the pump status. For example, the first electrical element may engage the second electrical element to form a closed circuit. The operational information may include a signal that a circuit has been closed and/or that a circuit has been opened (for instance, a binary I/O or on/off signal), and/or electrical information associated with a circuit (or lack thereof). Non-limiting electrical information may include, without limitation, resistance, voltage, amperage, inductance, capacitance, capacitor charge, and/or the like.
For example, a circuit may be formed (or alternatively, opened) responsive to engagement of a first pump element with a second pump element. The formation (or alternatively, breaking) of the circuit may be a signal of a pump event (such as switching from a fluid fill mode to a fluid delivery mode). In another example, a circuit may have different electrical properties based on engagement, position, or other status of pump components. For example, a resistance of a circuit may change as a first element travels with respect to a second element. A control element may determine status information (such as a location of the first element and/or second element) based on the change in resistance. The measured resistance may be compared to known resistance values that are indicative of a particular location of pumping elements or a pump status. As such, a threshold resistance may indicate a pump event or the location of a pump component.
The pump information or pump event may be used to control operational aspects of a fluid pump, such as changing fluid paths, activating pump elements, sending messages to a control device, error handling, and/or the like.
Although a snail cam and a piston are used in examples described in the present disclosure, embodiments are not so limited, as pump status assemblies may be used with various other types of pump components to determine a status of the component.
Other embodiments are contemplated in the present disclosure.
Fluid delivery device 160 may be or may include a wearable automatic fluid delivery device directly coupled to patient 150, for example, directly attached to the skin of the user via an adhesive and/or other attachment component. Fluid delivery device 160 may comprise one or more housings that house different elements of the fluid delivery device, for example, in the same housing or in different housings that connect together.
In some embodiments, fluid delivery device 160 may be or may include a medicament delivery device configured to deliver a liquid medicament, drug, therapeutic agent, or other medical fluid to a patient. Non-limiting examples of medicaments may include insulin, glucagon, glucagon like peptide (e.g., GLP-1), pramlintide, pain relief drugs, hormones, blood pressure medicines, morphine, methadone, chemotherapy drugs, proteins, antibodies, a combination of two or more of the foregoing, and/or the like.
In some embodiments, fluid delivery device 160 may be or may include an automatic insulin delivery (AID) device configured to deliver insulin (and/or other medication) to patient 150. For example, fluid delivery device 160 may be or may include a device the same or similar to an OmniPod® device or system provided by Insulet Corporation of Acton, Mass., United States, for example, as described in U.S. Pat. Nos. 7,303,549; 7,137,964; and/or 6,740,059, each of which is incorporated herein by reference in its entirety. Although an AID device and insulin are used in examples in the present disclosure, embodiments are not so limited, as fluid delivery device 160 may be or may include a device capable of storing and delivering any fluid therapeutic agent, drug, medicine, hormone, protein, antibody, and/or the like, including those mentioned above.
Fluid delivery device 160 may include a delivery system 162 having a number of components to facilitate automated delivery of a fluid to patient 150, including, without limitation, a reservoir 164 for storing the fluid, a pump 166 for transferring the fluid from reservoir 164, through a fluid path or conduit, and into the body of patient 150, and/or a power supply 168. Fluid delivery device 160 may include at least one penetration element (not shown) configured to be inserted into the skin of the patient to operate as a conduit between reservoir 164 and patient 150. For example, penetration element may include a cannula and/or a needle. Embodiments are not limited in this context, for example, as delivery system 162 may include more or fewer components.
In some embodiments, computing device 110 may be a smart phone, PDM, or other mobile computing form factor in wired or wireless communication with fluid delivery device 160. For example, computing device 110 and fluid delivery device 160 may communicate via various wireless protocols, including, without limitation, Wi-Fi (i.e., IEEE 802.11), radio frequency (RF), Bluetooth™, Zigbee™, near field communication (NFC), Medical Implantable Communications Service (MICS), and/or the like. In another example, computing device 110 and fluid delivery device 160 may communicate via various wired protocols, including, without limitation, universal serial bus (USB), Lightning, serial, and/or the like. Although computing device 110 (and components thereof) and fluid delivery device 160 are depicted as separate devices, embodiments are not so limited. For example, in some embodiments, computing device 110 and fluid delivery device 160 may be a single device. In another example, some or all of the components of computing device 110 may be included in fluid delivery device 160. For example, fluid delivery device 160 may include processor circuitry, memory unit, and/or the like. In some embodiments, each of computing device 110 and fluid delivery device 160 may include a separate processor circuitry, memory unit, and/or the like capable of facilitating insulin/medicament infusion processes according to some embodiments, either individually or in operative combination. Embodiments are not limited in this context.
In various embodiments, pump 210 may be a multi-dose reciprocating pump. In some embodiments, pump 210 may be configured to deliver about 0.25 microliters per pulse. In exemplary embodiments, pump 210 may have a footprint of about 23 millimeters (mm)×28 mm×12 mm.
In fluid delivery mode 350, pump chamber 306 is at least partially full of fluid (for instance, from a previous fluid fill mode 350). Rotation of ratchet 302 may cause rotation of snail cam 320. Projection 322 of piston 304 may ride along an outside surface of snail cam 320, pushing piston 304 into chamber 306 and, therefore, expelling the fluid out of chamber 306 and through needle 312 to patient.
In fluid fill mode 351, when piston 304 engages a drop off 308 of snail cam 320, piston 304 moves in a direction away from chamber 306 (toward the right in
The switch of the fluid delivery path from a fluid delivery path (for instance, a chamber-to-patient path) to a fluid fill path (for instance, a reservoir-to-chamber path) must occur when piston 304 engages drop off 308, otherwise the negative pressure resulting from movement of piston 304 away from chamber may negatively affect the patient, for example, drawing fluid from the patient rather than from the reservoir. Accordingly, some embodiments may provide a pump status assembly to indicate to pump control components to switch from a fluid delivery path to a fluid fill path at or before drop off 308 is encountered by piston 304.
For example, snail cam 420 may have an electronic element 432, such as a conductive strip, arranged on a surface thereof. A piston 404, or other pump component, may engage snail cam 420 during rotation of ratchet 402. In various embodiments, piston 404 may include at least one electrical element, such as a conductive post or other projection 440. When post 440 engages conductive strip 432, a completed circuit 434 is formed. A signal from completed circuit 434 may be received by one or more control components of a fluid delivery device. When post 440 is not engaged with or touching conductive strip 432, pump status assembly has an open circuit. In some embodiments, a signal that the circuit is open may be provided to control components of a fluid delivery device. Accordingly, in some embodiments, pump status assembly may operate as a “snail cam drop sensor” configured to detect when a portion of the pump, such as piston 404, is about to or has engaged drop off 408.
In some embodiments, conductive strip 432 may be arranged at a position at or near drop off 408 (for instance, at or near the end of the snail cam “ramp”). In this manner, closed circuit 434 may be formed and may cause a signal or pulse to be sent to indicate that piston 404 is about to reach drop off 408, and the fluid path should be switched from a fluid delivery path to a fluid fill path. As piston 404 moves off of drop off 408, the circuit may be opened to signal a switch of the fluid path associated with the fluid pump.
Although electrical element 432 is depicted as a conductive strip and electrical element 440 is depicted as a pair of conductive projections in
In various embodiments, electrical element 432 may be placed on or substantially on drop off 408 to signal when piston 404 has engaged drop off 408. In some embodiments, electrical element 432 may be placed a specified distance from drop off 408 to provide an indication that piston 404 is about to engage drop off 408. For example, the specified distance may be based on a set number of pulses (for instance, to predict piston 404 engagement with drop off 408 a set number of pulses (for example, 1-3 pulses) before the drop), a distance (for instance, a set number of millimeters before piston 404 engages drop off 408), percentage of snail cam 420 outer diameter, a time (for instance, a set number of milliseconds before piston engages drop off), and/or the like. Accordingly, a signal may be generated to indicate that piston 404 is a set a distance away from drop off 408. In some embodiments, electrical element 432 may include a plurality of elements configured to engage electrical element 440 at various locations along the outer surface of snail cam 420 as it rotates during pump operation.
As indicated in
As shown in step 550, piston 504 is engaging an outer surface of snail cam 520 at piston contact element 540. Flex sensor 542 is wrapped around an end of piston contact element 540 such that flex sensor 542 engages the outer surface of snail cam 520 and is in a flexed position (for instance, flexed toward piston 504). In some embodiments, flex sensor 542 may generate a signal indicating its current state (for instance, engaged with the outer surface of snail cam 520). At step 551, piston contact element 540 may be near drop off 508, for instance, near an edge of the snail cam ramp. Accordingly, flex sensor 542 may partially release and send a signal indicating its current state (for instance, in a partial-release form indicating piston 504 is nearing drop off 508).
At step 552, piston contact element 540 may have entered drop off 508 and flex sensor 542 may be fully or substantially fully extended. Accordingly, flex sensor 542 may generate a signal indicating its current state (for instance, in a fully-release form indicating piston 504 is within drop off 508). At step 553, piston contact element 540 may be exiting drop off 508 and re-engaging the outer surface or ramp of snail cam 520. Accordingly, flex sensor 542 may re-flex and generate a signal indicating its current state (for instance, in a fully-flexed form indicating piston 504 is engaging the ramp of snail cam 520).
In the embodiment shown in
While the present disclosure has been illustrated and described in detail in the drawings and foregoing description, the same is to be considered as illustrative and not restrictive in character, it being understood that only the certain embodiments have been shown and described and that all changes, alternatives, modifications and equivalents that come within the spirit of the disclosure are desired to be protected.
It should be understood that while the use of words such as preferable, preferably, preferred or more preferred utilized in the description above indicate that the feature so described may be more desirable, it nonetheless may not be necessary and embodiments lacking the same may be contemplated as within the scope of the present disclosure, the scope being defined by the claims that follow. In reading the claims, it is intended that when words such as “a,” “an,” “at least one,” or “at least one portion” are used there is no intention to limit the claim to only one item unless specifically stated to the contrary in the claim. When the language “at least a portion” and/or “a portion” is used the item can include a portion and/or the entire item unless specifically stated to the contrary.
This application claims the benefit of U.S. Provisional Patent Application No. 63/187,595, filed May 12, 2021, the contents of which are incorporated herein by reference in their entirety.
Number | Date | Country | |
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63187595 | May 2021 | US |