System and method for pressure sensor-based gas bubble detection for drug delivery devices

Abstract

A drug delivery device may include a pressure sensor, a microprocessor, a fluid pathway including a reservoir, a pump downstream of the reservoir, and / or a fluid line downstream of the pump. The reservoir may be configured to receive a fluid, and the pump may be configured to deliver the fluid from the reservoir to the fluid line. The pressure sensor may be configured to measure a pressure in the fluid pathway downstream of the pump. The microcontroller may be programmed and / or configured to: receive, from the pressure sensor, the pressure measured in the fluid path downstream of the pump when the fluid is delivered to the fluid line; determining whether the fluid delivered to the fluid line includes gas bubbles based on the pressure measured in the fluid path; and controlling an output device to provide an indication associated with determining the gas bubble.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to U.S. patent application No. 17 / 859,627, filed on July 7, 2022, entitled “System and Method for Pressure Sensor Based Gas Bubble Detection for a Drug Delivery Device,” the entire disclosure of which is incorporated herein by reference in its entirety.

[0003] BACKGROUND OF THE INVENTION

[0004] field

[0005] The present disclosure relates to devices and methods for pressure sensor-based gas bubble detection for drug delivery devices.

[0006] Description of Related Technology

[0007] The benefit of a wearable medical device, such as an auto-injector, is to provide treatment to a patient at a location remote from a clinical facility and / or while being worn separately under the patient's clothing. The wearable medical device can be applied to the patient's skin and configured to automatically deliver a dose of a pharmaceutical composition within a predetermined time period (such as after a 27-hour delay) after the wearable medical device is applied to the patient's skin. After the device delivers the pharmaceutical composition to the patient, the patient can then remove and dispose of the device.

[0008] In the case of fluid injection or infusion, certain drugs may be prescribed for administration with a strictly controlled dosage regimen (e.g., a precise dose may be prescribed to be delivered with controlled timing, etc.). Injection devices typically implement controlled flow rates and dosage regimens based on volumetric dosage, where the system applies a known volume displacement to the fluid being administered. Exemplary systems that implement volume-based dosage control are syringe pumps, oscillo-rotative pumps, systems with moving pistons, peristaltic pumps, and membrane and diaphragm pumps.

[0009] A subset of these pumps works on the basis of a "dosing chamber element" that is cyclically filled and emptied. A peculiarity of these systems is that the fluid path upstream of the pump may not be in direct communication with the path downstream of the pump, allowing different pressures to build up in these respective fluid paths.

[0010] The presence of gas bubbles or air bubbles in fluids is a ubiquitous challenge in the field of precision dosing because these gas bubbles impair control of the volume of the drug being administered by occupying part of the volume of the fluid path being flowed, which may result in underdosing and / or may negatively impact the therapeutic treatment being administered. Solutions to gas bubbles exist in the form of bubble traps and optical or ultrasonic bubble detection systems. However, these systems force the addition of components in the fluid path or the use of sensors that may be expensive and / or consume a lot of power, which may be a particular concern for wearable devices. Summary of the invention

[0011] Thus, systems, devices, products, apparatus and / or methods are provided that provide improved gas bubble detection for drug delivery devices.

[0012] According to some non-limiting embodiments or aspects, a drug delivery device is provided, which includes: a fluid pathway, the fluid pathway including a reservoir, a pump located downstream of the reservoir, and a fluid line located downstream of the pump, wherein the reservoir is configured to receive a fluid, and wherein the pump is configured to deliver the fluid from the reservoir to the fluid line; a pressure sensor, the pressure sensor configured to measure the pressure in the fluid pathway downstream of the pump; and a microcontroller, the microcontroller being programmed and / or configured to: receive from the pressure sensor the pressure measured in the fluid pathway downstream of the pump when the fluid is delivered to the fluid line; determine whether the fluid delivered to the fluid line includes gas bubbles based on the pressure measured in the fluid pathway downstream of the pump when the fluid is delivered to the fluid line; and control an output device to provide an indication associated with determining whether the fluid delivered to the fluid line includes gas bubbles.

[0013] In some non-limiting embodiments or aspects, the pump includes a dosing chamber, wherein the pump is configured to cyclically: (i) pump the reservoir while the dosing chamber is in fluid communication with the reservoir but not in fluid communication with the fluid line and (ii) fluidly connect the dosing chamber to the fluid line, and wherein, when the dosing chamber is fluidly connected to the fluid line, the fluid is delivered to the fluid line.

[0014] In some non-limiting embodiments or aspects, the microcontroller is also programmed and / or configured to: receive from the pressure sensor a pressure measured in the fluid pathway downstream of the pump before fluidly connecting the dose chamber to the fluid line; and determine a baseline pressure based on the pressure measured in the fluid pathway downstream of the pump before fluidly connecting the dose chamber to the fluid line, wherein the microcontroller is programmed and / or configured to determine whether the fluid delivered to the fluid line includes gas bubbles based on the pressure measured in the fluid pathway downstream of the pump when the fluid is delivered to the fluid line and the baseline pressure.

[0015] In some non-limiting embodiments or aspects, the microcontroller is programmed and / or configured to determine whether the fluid delivered to the fluid line includes gas bubbles by: comparing the pressure measured in the fluid pathway downstream of the pump when the fluid is delivered to the fluid line with a threshold pressure; and in response to the pressure measured in the fluid pathway downstream of the pump when the fluid is delivered to the fluid line satisfying the threshold pressure, determining that the fluid delivered to the fluid line includes gas bubbles.

[0016] In some non-limiting embodiments or aspects, the microcontroller is programmed and / or configured to determine whether the fluid delivered to the fluid line includes gas bubbles by: determining a rate of change associated with the pressure measured in the fluid pathway downstream of the pump when the fluid is delivered to the fluid line based on the pressure measured in the fluid pathway downstream of the pump when the fluid is delivered to the fluid line; comparing the rate of change associated with the pressure measured in the fluid pathway downstream of the pump when the fluid is delivered to the fluid line with a threshold rate of change; and determining that the fluid delivered to the fluid line includes gas bubbles in response to the rate of change associated with the pressure measured in the fluid pathway downstream of the pump when the fluid is delivered to the fluid line satisfying the threshold rate of change.

[0017] In some non-limiting embodiments or aspects, the microcontroller is also programmed and / or configured to: receive a pressure associated with the fluid pathway upstream of the pump; and based on the pressure associated with the fluid pathway upstream of the pump, determine the following: the pressure measured in the fluid pathway downstream of the pump when the fluid is delivered to the fluid line; and at least one of the size of the fluid pathway, the volume of the gas bubbles included in the fluid delivered to the fluid line, the volume of the fluid delivered to the fluid line, or any combination thereof.

[0018] In some non-limiting embodiments or aspects, the microcontroller is programmed and / or configured to determine whether the fluid delivered to the fluid line includes gas bubbles by: determining a pressure change over a period of time based on the pressure measured in the fluid passage downstream of the pump when the fluid is delivered to the fluid line; comparing the pressure change over the period of time with a threshold change; and in response to the pressure change over the period of time satisfying the threshold change, determining that the fluid delivered to the fluid line during the period of time includes gas bubbles.

[0019] In some non-limiting embodiments or aspects, the microcontroller is also programmed and / or configured to determine at least one of the volume of the gas bubbles included in the fluid delivered to the fluid pipeline, the volume of the fluid delivered to the fluid pipeline, or any combination thereof based on the pressure change over the period of time.

[0020] In some non-limiting embodiments or aspects, the pressure sensor includes at least one of: an absolute pressure sensor, a differential pressure sensor, or any combination thereof.

[0021] In some non-limiting embodiments or aspects, the microcontroller is also programmed and / or configured to: receive from the pressure sensor the pressure measured in the fluid pathway downstream of the pump during priming of the pump; and determine whether the pump is fully primed based on the pressure measured in the fluid pathway downstream of the pump during priming of the pump.

[0022] According to some non-limiting embodiments or methods, a method for gas bubble detection based on a pressure sensor for a drug delivery device is provided, the drug delivery device including a fluid pathway, the fluid pathway including a reservoir configured to receive a fluid, a pump located downstream of the reservoir, and a fluid line located downstream of the pump, the method comprising: utilizing the pump to deliver the fluid from the reservoir to the fluid line; utilizing a pressure sensor to measure the pressure in the fluid pathway downstream of the pump when the fluid is delivered to the fluid line; utilizing a microcontroller to receive the pressure measured in the fluid pathway downstream of the pump when the fluid is delivered to the fluid line; utilizing the microcontroller to determine whether the fluid delivered to the fluid line includes gas bubbles based on the pressure measured in the fluid pathway downstream of the pump when the fluid is delivered to the fluid line; and utilizing the microcontroller to control an output device to provide an indication associated with determining whether the fluid delivered to the fluid line includes gas bubbles.

[0023] In some non-limiting embodiments or aspects, the pump includes a dosing chamber, wherein the pump is configured to cyclically: (i) draw from the reservoir while the dosing chamber is in fluid communication with the reservoir but not in fluid communication with the fluid line and (ii) fluidly connect the dosing chamber to the fluid line, and wherein, when the dosing chamber is fluidly connected to the fluid line, deliver the fluid to the fluid line.

[0024] In some non-limiting embodiments or aspects, the method further includes: before fluidly connecting the dosing chamber to the fluid line: measuring the pressure in the fluid passage downstream of the pump using the pressure sensor; and determining a baseline pressure based on the pressure measured in the fluid passage downstream of the pump before fluidly connecting the dosing chamber to the fluid line, wherein whether the fluid delivered to the fluid line includes gas bubbles is determined based on the pressure measured in the fluid passage downstream of the pump when the fluid is delivered to the fluid line and the baseline pressure.

[0025] In some non-limiting embodiments or aspects, determining whether the fluid delivered to the fluid pipeline includes gas bubbles includes: comparing the pressure measured in the fluid passage downstream of the pump when the fluid is delivered to the fluid pipeline with a threshold pressure; and in response to the pressure measured in the fluid passage downstream of the pump when the fluid is delivered to the fluid pipeline satisfying the threshold pressure, determining that the fluid delivered to the fluid pipeline includes gas bubbles.

[0026] In some non-limiting embodiments or aspects, determining whether the fluid delivered to the fluid pipeline includes gas bubbles includes: determining a rate of change associated with the pressure measured in the fluid pathway downstream of the pump when the fluid is delivered to the fluid pipeline based on the pressure measured in the fluid pathway downstream of the pump when the fluid is delivered to the fluid pipeline; comparing the rate of change associated with the pressure measured in the fluid pathway downstream of the pump when the fluid is delivered to the fluid pipeline with a threshold rate of change; and determining that the fluid delivered to the fluid pipeline includes gas bubbles in response to the rate of change associated with the pressure measured in the fluid pathway downstream of the pump when the fluid is delivered to the fluid pipeline satisfying the threshold rate of change.

[0027] In some non-limiting embodiments or aspects, the method further includes: receiving, using the microcontroller, a pressure associated with the fluid pathway upstream of the pump; and determining, using the microcontroller, based on the pressure associated with the fluid pathway upstream of the pump, the following items: the pressure measured in the fluid pathway downstream of the pump when the fluid is delivered to the fluid line; and at least one of the size of the fluid pathway, the volume of the gas bubbles included in the fluid delivered to the fluid line, the volume of the fluid delivered to the fluid line, or any combination thereof.

[0028] In some non-limiting embodiments or aspects, determining whether the fluid delivered to the fluid line includes gas bubbles includes: determining a pressure change over a period of time based on the pressure measured in the fluid passage downstream of the pump when the fluid is delivered to the fluid line; comparing the pressure change over the period of time with a threshold change; and in response to the pressure change over the period of time satisfying the threshold change, determining that the fluid delivered to the fluid line during the period of time includes gas bubbles.

[0029] In some non-limiting embodiments or aspects, the method further includes: utilizing the microcontroller to determine, based on the pressure change over the period of time, at least one of the volume of the gas bubbles included in the fluid delivered to the fluid pipeline, the volume of the fluid delivered to the fluid pipeline, or any combination thereof.

[0030] In some non-limiting embodiments or aspects, the method further includes: measuring, using the pressure sensor, another pressure in the fluid pathway downstream of the pump during startup of the pump; receiving, using the microcontroller, the other pressure measured in the fluid pathway downstream of the pump during startup of the pump from the pressure sensor; and determining whether the pump is fully started based on the pressure measured in the fluid pathway downstream of the pump during startup of the pump.

[0031] According to some non-limiting embodiments or aspects, a computer program product for pressure sensor-based gas bubble detection for a drug delivery device, the drug delivery device comprising a microcontroller, a pressure sensor, and a fluid pathway, the fluid pathway comprising a reservoir configured to receive a fluid, a pump located downstream of the reservoir, and a fluid line located downstream of the pump, the computer program product comprising at least one non-transitory computer-readable medium, the at least one non-transitory computer-readable medium comprising program instructions that, when executed by the microcontroller, cause the microcontroller to: control the pump to flow from the reservoir; The reservoir delivers the fluid to the fluid line; controls the pressure sensor to measure the pressure in the fluid passage downstream of the pump when the fluid is delivered to the fluid line; and receives from the pressure sensor the pressure measured in the fluid passage downstream of the pump when the fluid is delivered to the fluid line; determines whether the fluid delivered to the fluid line includes gas bubbles based on the pressure measured in the fluid passage downstream of the pump when the fluid is delivered to the fluid line; and controls the output device to provide an indication associated with the determination of whether the fluid delivered to the fluid line includes gas bubbles. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The above and other features and advantages of the present disclosure and the manner in which they are achieved will become more apparent, and the present disclosure itself will be better understood, by referring to the following description of embodiments of the present disclosure taken in conjunction with the accompanying drawings, in which:

[0033] Figure 1 is a perspective view of a drug delivery device according to one aspect or embodiment of the present application;

[0034] Figure 2 for Figure 1 A perspective view of a drug delivery device with a top cover removed;

[0035] Figure 3 for Figure 1 Schematic diagram of a drug delivery device;

[0036] Figure 4 A schematic diagram of a system for gas bubble detection based on a pressure sensor according to one aspect or embodiment of the present application;

[0037] Figure 5A and Figure 5B for Figure 1 A graphic representation of an example pressure signature and a graphic representation of an example motor current signature for a drug delivery device of FIG.

[0038] Figure 6 for Figure 1 Graphics of example pressure symbols and motor current symbols for a drug delivery device.

[0039] Figure 7 for Figure 1 Graphic illustration of example pressure markers for a drug delivery device.

[0040] Figure 8 for Figure 1 Another example graphic of a pressure marker for a drug delivery device.

[0041] Fig. 9 for Figure 1

[0026] Still another example of a graphic representation of a pressure marker and a motor current marker for a drug delivery device of FIG.

[0042] Fig.10 The present invention is a flowchart of a gas bubble detection process based on a pressure sensor for a drug delivery device according to one aspect or embodiment of the present application.

[0043] Corresponding reference numerals indicate corresponding parts throughout the several views.The exemplifications set out herein illustrate exemplary embodiments of the disclosure, and such exemplifications should not be construed as limiting the scope of the disclosure in any way. DETAILED DESCRIPTION

[0044] Spatial or directional terms (such as "left", "right", "inner", "outer", "upper", and "lower", etc.) should not be considered limiting, as aspects or embodiments of the present disclosure may assume various alternative orientations.

[0045] All numbers used in the specification and claims are to be understood as being modified in all cases by the term "about". "About" means a range of plus or minus ten percent of the value recorded. As used in the specification and claims, the singular forms "a", "an", and "the" include plural references unless the context clearly indicates otherwise. The terms "first", "second", etc. are not intended to refer to any particular order or sequence, but rather to different conditions, characteristics, or elements. "At least" means "greater than or equal to".

[0046] refer to Figures 1 to 3 , the drug delivery device 10 includes a reservoir 12, a power source 14, an insertion mechanism 16, control electronics 18, a cover 20, and a base 22. In one aspect or embodiment, the drug delivery device 10 is a wearable automatic injector, such as an insulin or bone marrow stimulant delivery device. The drug delivery device 10 can be mounted on the patient's skin and triggered to inject a pharmaceutical composition from the reservoir 12 into the patient's body. The drug delivery device 10 can be pre-filled with the pharmaceutical composition, or the drug delivery device 10 can be filled with the pharmaceutical composition by the patient or a medical professional before use.

[0047] The drug delivery device 10 is configured to deliver a dose of a drug composition (e.g., any desired medicament) to a patient via subcutaneous injection at a slow, controlled injection rate. An exemplary duration of delivery achieved by the drug delivery device 10 may be in the range of about 5 minutes to about 60 minutes, but is not limited to this exemplary range. An exemplary volume of the drug composition delivered by the drug delivery device 10 may be in the range of about 0.1 milliliters to about 10 milliliters, but is not limited to this exemplary range. The volume of the drug composition delivered to the patient may be adjusted.

[0048] Reference again Figures 1 to 3In one aspect or embodiment, the power source 14 is a direct current (DC) power source that includes one or more batteries. The control electronics 18 include a microcontroller 24 that controls actuation of the drug delivery device 10, sensing electronics 26, a pump and valve controller 28, sensing electronics 30, and deployment electronics 32. The drug delivery device 10 includes a fluid subsystem that includes a reservoir 12, a volume sensor 34 for the reservoir 12, a reservoir fill port 36, and a metering system 38 that includes a pump and valve actuator 40 and a pump and valve mechanism 42. The fluid subsystem may also include an occlusion sensor 44, a deployment actuator 46, a cannula 48 for insertion into the patient's skin, and a fluid line 50 in fluid communication with the reservoir 12 and the cannula 48. In one aspect or embodiment, the occlusion sensor 44 includes a pressure sensor, such as described herein with respect to Figure 4 The pressure sensor 54 is described in more detail. In one aspect or embodiment, the insertion mechanism 16 is configured to move the cannula 48 from a retracted position completely within the device 10 to an extended position in which the cannula 48 extends outside the device 10. The drug delivery device 10 can operate in the same manner as discussed in U.S. Patent No. 10,449,292 to Pizzochero et al., which is incorporated herein by reference.

[0049] In one aspect or embodiment, the fluid pathway is formed by the reservoir 12, the pump and valve mechanism 42 located downstream of the reservoir 12, and the fluid line 50 located downstream of the pump and valve mechanism 42. For example, the reservoir 12 can be configured to receive a fluid, and the pump and valve mechanism 42 can be configured to deliver the fluid from the reservoir 12 to the fluid line 50.

[0050] refer to Figure 4In one aspect or embodiment, the pump and valve mechanism 42 includes a dosing chamber 52. The pump and valve mechanism 42 can be configured to cyclically (i) draw the reservoir 12 while the dosing chamber 52 is in fluid communication with the reservoir 12 but not in fluid communication with the fluid line 50 and (ii) fluidly connect the dosing chamber 52 with the fluid line 12 (e.g., while the dosing chamber 52 is not in fluid communication with the reservoir 12, etc.). For example, the pump and valve mechanism 42 can draw the reservoir 12 while the dosing chamber 52 is in fluid communication with the reservoir 12 but not in fluid communication with the fluid line 50 to fill the dosing chamber 52 with fluid from the reservoir 12, and the pump and valve mechanism 42 can connect the dosing chamber 52 with the fluid line 50 to empty the fluid in the dosing chamber 52 and deliver fluid to the fluid line 50 (e.g., while the dosing chamber 52 is not in fluid communication with the reservoir 12, etc.). In this way, fluid paths upstream of the pump and valve mechanism 42 (e.g., upstream of the dosing chamber 52, etc.) may not be in direct fluid communication with fluid paths downstream of the pump and valve mechanism 42, thereby allowing different pressures to be established in these respective upstream and downstream fluid paths.

[0051] Still refer to Figure 4 , the drug delivery device 10 may include a pressure sensor 54. The pressure sensor 54 may be configured to measure the pressure in a fluid path formed by the reservoir 12, the pump and valve mechanism 42 located downstream of the reservoir 12, and the fluid line 50 located downstream of the pump and valve mechanism 42. The pressure sensor 54 may be located downstream of the pump and valve mechanism 42 in the fluid path and / or upstream of the pump and valve mechanism 42 in the fluid path. For example, the pressure sensor 54 may be configured to measure the pressure in the fluid path downstream of the pump and valve mechanism 42 (e.g., downstream of the dosing chamber 52, etc.) and / or the pressure in the fluid path upstream of the pump and valve mechanism 42 (e.g., upstream of the dosing chamber 52, etc.). The pressure sensor 54 may include at least one of the following: an absolute pressure sensor, a differential pressure (e.g., a gauge pressure) sensor, or any combination thereof. The pressure sensor 54 may be miniaturized, may have high resolution, may be cost-effective, and / or may be optimized for low power consumption.

[0052] The microcontroller 24 may be programmed and / or configured to: receive from the pressure sensor 54 a pressure measured in the fluid pathway downstream of the pump and valve mechanism 42 when fluid is delivered to the fluid line (e.g., when the dosing chamber 52 is fluidly connected to a downstream fluid pathway including the fluid line 50, etc.); determine, based on the pressure measured in the fluid pathway downstream of the pump and valve mechanism 42 when fluid is delivered to the fluid line 50 (e.g., the pressure measured when the dosing chamber 52 is fluidly connected to a downstream fluid pathway including the fluid line 50, etc.), whether the fluid delivered to the fluid line includes one or more gas bubbles; and / or control an output device (e.g., a display, a light emitting diode (LED), a speaker, etc.) to provide an indication associated with determining whether the fluid delivered to the fluid line includes one or more gas bubbles. The output device may be included in and / or integrated with the drug delivery device 10, and / or the output device may be included in and / or integrated with an external device that is located outside the drug delivery device 10 and communicates with the drug delivery device 10 (e.g., wireless and / or wireless communication, etc.), such as a remote computing device and / or a wireless controller (WC) 500 discussed in U.S. Pat. No. 10,449,292 to Pizzochero et al., which is incorporated herein by reference.

[0053] In this way, and with reference to Figure 5A , Figure 5B and Figures 6 to 9, non-limiting embodiments or aspects of the present application can utilize the higher compressibility of gases than liquids, and in combination with the cyclic application of a known volume change in the dosing chamber 52 when at least a portion of the fluid path is connected to the fluid line 50 (e.g., an injection port, etc.) and a pressure sensor located downstream relative to the extraction system, to detect the pressure signature of one or more gas bubbles being drawn through the fluid system. For example, when the pump and valve mechanism 42 applies a known volume change over a known period of time, the pressure in the downstream fluid path downstream of the dosing chamber 52 is expected to increase by at least a known value due to the fluid movement in the fluid line 50. However, the presence of gas bubbles in the drawn volume inhibits the pressure increase and can be reliably detected by the pressure sensor 54. In addition, when the dosing chamber becomes fluidly connected to the downstream fluid line 50, the increased compliance of the gas bubbles in the dosing chamber 52, together with the pressure difference between the upstream and downstream fluid paths relative to the dosing chamber 52, can cause a pressure change. If the pressure in the downstream fluid path is higher, the pressure drop can be identified as a signature or presence of one or more air or gas bubbles. Using the pressure of the upstream fluid path, either by direct measurement or inference (e.g., known to be at atmospheric pressure, etc.), the volume of one or more gas bubbles can be determined based on at least one of: pressure changes in the downstream fluid path, the volume of the fluid system, the size of the fluid system, the rheological properties of the fluid in the fluid line, or any combination thereof.

[0054] In one aspect or embodiment, the microcontroller 24 is programmed and / or configured to determine whether the fluid delivered to the fluid line 50 includes gas bubbles by comparing a pressure measured in the fluid pathway downstream of the pump and valve mechanism 42 when the fluid is delivered to the fluid line 50 (e.g., a maximum or peak pressure achieved when the dosing chamber 52 is in fluid communication with the downstream fluid pathway including the fluid line 50, a change or fluctuation in pressure in the downstream fluid pathway over a period of time in response to the fluid connection of the dosing chamber 52 to the downstream fluid pathway including the fluid line 50, etc.) with a threshold pressure (e.g., a threshold peak pressure, a threshold pressure change or fluctuation, etc.); and determining that the fluid delivered to the fluid line 50 includes gas bubbles in response to the pressure measured in the fluid pathway downstream of the pump and valve mechanism 42 when the fluid is delivered to the fluid line 50 satisfying the threshold pressure. For example, the microcontroller 24 may compare a peak pressure reached during a draw (e.g., when the dosing chamber 52 of the pump and valve mechanism 42 is connected to a downstream fluid path, etc.) to a threshold pressure, and determine that the fluid delivered to the fluid line 50 includes gas bubbles in response to the peak pressure satisfying the threshold pressure (e.g., in response to the peak pressure being below the threshold pressure, in response to a pressure or change or fluctuation being above a threshold pressure change, etc.).

[0055] In one aspect or embodiment, the microcontroller 24 is programmed and / or configured to determine whether the fluid delivered to the fluid line includes gas bubbles by: determining a rate of change associated with the pressure measured in the fluid pathway downstream of the pump and valve mechanism 42 when the fluid is delivered to the fluid line 50 (e.g., when the dosing chamber 52 of the pump and valve mechanism 42 is connected to the downstream fluid path, etc.), based on the pressure measured in the fluid pathway downstream of the pump and valve mechanism 42 when the fluid is delivered to the fluid line 50; comparing the rate of change associated with the pressure measured in the fluid pathway downstream of the pump and valve mechanism 42 when the fluid is delivered to the fluid line 50 with a threshold rate of change; and determining that the fluid delivered to the fluid line 50 includes gas bubbles in response to the rate of change associated with the pressure measured in the fluid pathway downstream of the pump and valve mechanism 42 when the fluid is delivered to the fluid line 50 satisfying the threshold rate of change. For example, the microcontroller 24 can compare the rate of change associated with the pressure measured in the fluid pathway downstream of the pump and valve mechanism 42 during extraction (e.g., rate of pressure increase, rate of pressure decrease, rate of rate of pressure increase, rate of rate of pressure decrease, etc.) to a threshold rate of change, and in response to the measured rate of change satisfying the threshold rate (e.g., being below the threshold rate, etc.), determine that the fluid delivered to the fluid line 50 includes gas bubbles.

[0056] In one aspect or embodiment, the microcontroller 24 is further programmed and / or configured to: receive from the pressure sensor 54 a pressure measured in the fluid pathway downstream of the pump and valve mechanism 42 before fluidly connecting the dosing chamber 52 to the fluid line 50 (e.g., before a volume change begins in the downstream fluid pathway, etc.); and determine a baseline pressure based on the pressure measured in the fluid pathway downstream of the pump and valve mechanism 42 before fluidly connecting the dosing chamber 52 to the fluid line 50. In such an example, the microcontroller 24 may be programmed and / or configured to determine whether the fluid delivered to the fluid line 50 includes gas bubbles based on the pressure measured in the fluid pathway downstream of the pump when delivering the fluid to the fluid line 50 and the baseline pressure. For example, a pressure marker measured in the fluid pathway may be offset by a baseline pressure marker defined by a pressure value measured before connecting the dosing chamber 52 to the downstream fluid pathway. In this way, non-limiting embodiments or aspects of the present application can compensate for the effects on the pressure signature due to mechanical compliance of the extraction system (e.g., spring effects, deformability of components, mechanical recoil, etc.) when the dosing chamber 52 is connected to the downstream fluid pathway. For example, the pressure signature measured when the dosing chamber 52 is connected to the downstream fluid pathway can be used to detect the presence of air or gas in response to a pressure change above a predefined threshold after compensation for system effects.

[0057] In one aspect or embodiment, the microcontroller 24 is further programmed and / or configured to: receive a pressure associated with the fluid pathway upstream of the pump and valve mechanism 42 (e.g., a direct measurement of the pressure sensor 54 or another pressure sensor in the upstream fluid pathway, a known atmospheric pressure, etc.); and determine, based on the pressure associated with the fluid pathway upstream of the pump and valve mechanism 42, at least one of the pressure measured in the fluid pathway downstream of the pump and valve mechanism 42 when delivering fluid to the fluid line 50, and the size of the fluid pathway (e.g., the size of the reservoir, the dosing chamber 52, the fluid line 50, the upstream fluid pathway, and / or the downstream fluid pathway, etc.), the volume of gas bubbles included in the fluid delivered to the fluid line 50, the volume of the fluid delivered to the fluid line 50, or any combination thereof. In this way, the pressure change can be used to determine the volume of gas and / or liquid delivered to the downstream fluid path.

[0058] In one aspect or embodiment, the microcontroller 24 is further programmed and / or configured to determine the relative volume of gas in the fluid delivered to the fluid line 50 by applying a combination of the Hagen-Poiseuille equation and known gas laws to measured pressure markers in the fluid passageway taking into account at least one of the fluid properties, the extraction scheme, and the dimensions of the fluid passageway. For example, the microcontroller 24 can determine at least one of the volume of gas bubbles included in the fluid delivered to the fluid line 50, the volume of the fluid delivered to the fluid line 50, or any combination thereof based on the pressure change over a period of time.

[0059] In one aspect or embodiment, the microcontroller 24 is further programmed and / or configured to: receive from the pressure sensor 54 a pressure measured in the fluid pathway downstream of the pump and valve mechanism 42 during priming of the pump and valve mechanism 42; and determine whether the pump and valve mechanism 42 is fully primed based on the pressure measured in the fluid pathway downstream of the pump and valve mechanism 42 during priming of the pump and valve mechanism 42. For example, the microcontroller 24 may compare the pressure measured in the fluid pathway downstream of the pump and valve mechanism 42 during priming of the pump and valve mechanism 42 (e.g., a maximum or peak pressure reached during priming, a change or fluctuation in pressure during priming, etc.) to a threshold priming pressure, and determine that the downstream fluid path is fully primed in response to the measured priming pressure satisfying the threshold priming pressure.

[0060] In one aspect or embodiment, the indication associated with determining whether the fluid delivered to the fluid line 50 includes gas bubbles includes notification of successful completion of treatment (e.g., no gas bubbles, etc.), notification of a failure mode and / or inclusion of gas bubbles in the fluid delivered to the fluid line 50, notification of the volume of fluid delivered to the fluid line, notification of the volume of gas bubbles in the fluid delivered to the fluid line, notification of the startup status of the device 10 (e.g., fully started, not fully started, etc.), or any combination thereof.

[0061] In one aspect or embodiment, the microcontroller 24 can, in response to detecting a gas bubble, adjust the cyclic extraction of the pump and valve mechanism 42 to compensate for the detected gas bubble (e.g., by adding additional pump cycles, by adjusting the pump cycle duration of a pump cycle phase, etc.). For example, the microcontroller 24 can also be programmed and / or configured to compare the volume of the gas bubble and / or the delivered fluid to a threshold or specified volume, and in response to the volume of the gas bubble and / or the delivered fluid satisfying the threshold or specified volume, automatically adjust the cyclic extraction of the pump and valve mechanism 42 to compensate for the volume of the detected gas bubble (e.g., by adding additional pump cycles, by adjusting the pump cycle duration of a pump cycle phase, etc.).

[0062] refer to Fig.10 In one aspect or embodiment, a process 1000 for pressure sensor-based gas bubble detection for a drug delivery device 10 includes: receiving a fluid in a reservoir 12 (step 1002); delivering the fluid from the reservoir 12 to a fluid line 50 using a pump and valve mechanism 42 (step 1004); measuring the pressure in a fluid pathway downstream of the pump and valve mechanism 42 when delivering the fluid to the fluid line 50 using a pressure sensor 54 (step 1006); receiving the pressure measured in the fluid pathway using a microcontroller 24 (step 1008); determining, using the microcontroller 24, based on the pressure measured in the fluid pathway, whether the fluid delivered to the fluid line 50 includes gas bubbles (step 1010); and controlling an output device using the microcontroller 24 to provide an indication associated with determining whether the fluid delivered to the fluid line 50 includes gas bubbles (step 1012).

[0063] Thus, non-limiting embodiments or aspects of the present application may provide a drug delivery device that has low manufacturing costs, extremely low power consumption, is compact in size, and / or has low computing power requirements, which may utilize hardware that may be present in an extraction system and / or may be used with flexible reservoir bags, rigid containers, and / or syringe-like containers.

[0064] Although for the purpose of illustration, various aspects or embodiments have been described in detail based on what are currently considered to be the most practical and preferred embodiments, it should be understood that such details are only for this purpose, and the various aspects or embodiments of the present disclosure are not limited to the disclosed embodiments, but on the contrary, the various aspects or embodiments of the present disclosure are intended to cover modifications and equivalent arrangements within the spirit and scope of the appended claims. For example, it should be understood that the present disclosure contemplates that, to the extent possible, one or more features of any embodiment can be combined with one or more features of any other embodiment.

Claims

1. A drug delivery device, comprising: a fluid pathway comprising a reservoir, a pump downstream of the reservoir, and a fluid line downstream of the pump, wherein the reservoir is configured to receive a fluid, and wherein the pump is configured to deliver the fluid from the reservoir to the fluid line; a pressure sensor configured to measure pressure in the fluid passage downstream of the pump; and A microcontroller, the microcontroller being programmed and / or configured to: receiving from the pressure sensor a pressure measured in the fluid passageway downstream of the pump when delivering the fluid to the fluid line; determining whether the fluid delivered to the fluid line includes gas bubbles based on the pressure measured in the fluid passageway downstream of the pump when the fluid is delivered to the fluid line; and An output device is controlled to provide an indication associated with determining whether the fluid delivered to the fluid line includes gas bubbles.

2. The drug delivery device according to claim 1, wherein: The pump includes a dosing chamber, wherein the pump is configured to cyclically: (i) draw from the reservoir while the dosing chamber is in fluid communication with the reservoir but not in fluid communication with the fluid line and (ii) fluidly connect the dosing chamber with the fluid line, and wherein the fluid is delivered to the fluid line when the dosing chamber is in fluid communication with the fluid line.

3. The drug delivery device according to claim 2, wherein: The microcontroller is also programmed and / or configured to: receiving from the pressure sensor a pressure measured in the fluid passageway downstream of the pump prior to fluidly connecting the dosing chamber with the fluid line; as well as A baseline pressure is determined based on the pressure measured in the fluid pathway downstream of the pump before fluidly connecting the dosing chamber with the fluid line, wherein the microcontroller is programmed and / or configured to determine whether the fluid delivered to the fluid line includes gas bubbles based on the pressure measured in the fluid pathway downstream of the pump when delivering the fluid to the fluid line and the baseline pressure.

4. The drug delivery device according to claim 1, wherein: The microcontroller is programmed and / or configured to determine whether the fluid delivered to the fluid line includes gas bubbles by: comparing the pressure measured in the fluid passageway downstream of the pump when delivering the fluid to the fluid line to a threshold pressure; as well as In response to the pressure measured in the fluid passageway downstream of the pump satisfying the threshold pressure when the fluid is delivered to the fluid line, it is determined that the fluid delivered to the fluid line includes gas bubbles.

5. The drug delivery device according to claim 1, wherein: The microcontroller is programmed and / or configured to determine whether the fluid delivered to the fluid line includes gas bubbles by: determining, based on the pressure measured in the fluid passageway downstream of the pump when delivering the fluid to the fluid line, a rate of change associated with the pressure measured in the fluid passageway downstream of the pump when delivering the fluid to the fluid line; comparing the rate of change associated with the pressure measured in the fluid passageway downstream of the pump when delivering the fluid to the fluid line to a threshold rate of change; as well as Responsive to the rate of change associated with the pressure measured in the fluid passageway downstream of the pump when delivering the fluid to the fluid line satisfying the threshold rate of change, it is determined that the fluid delivered to the fluid line includes gas bubbles.

6. The drug delivery device according to claim 1, wherein: The microcontroller is also programmed and / or configured to: receiving a pressure associated with the fluid passage upstream of the pump; and Based on the pressure associated with the fluid pathway upstream of the pump, determine the following: the pressure measured in the fluid pathway downstream of the pump when the fluid is delivered to the fluid pipeline; and at least one of the size of the fluid pathway, the volume of the gas bubbles included in the fluid delivered to the fluid pipeline, the volume of the fluid delivered to the fluid pipeline, or any combination thereof.

7. The drug delivery device according to claim 1, wherein: The microcontroller is programmed and / or configured to determine whether the fluid delivered to the fluid line includes gas bubbles by: determining a pressure change over a period of time based on the pressure measured in the fluid passageway downstream of the pump while delivering the fluid to the fluid line; comparing the change in pressure over the period of time to a threshold change; as well as In response to the pressure change over the period of time satisfying the threshold change, it is determined that the fluid delivered to the fluid line during the period of time includes gas bubbles.

8. The drug delivery device according to claim 7, wherein: The microcontroller is also programmed and / or configured to: At least one of a volume of the gas bubbles included in the fluid delivered to the fluid line, a volume of the fluid delivered to the fluid line, or any combination thereof is determined based on the pressure change over the period of time.

9. The drug delivery device according to claim 1, wherein: The pressure sensor includes at least one of: an absolute pressure sensor, a differential pressure sensor, or any combination thereof.

10. The drug delivery device according to claim 1, wherein: The microcontroller is also programmed and / or configured to: receiving from the pressure sensor the pressure measured in the fluid passage downstream of the pump during activation of the pump; and Based on the pressure measured in the fluid passage downstream of the pump during priming of the pump, it is determined whether the pump is fully primed.

11. A method for pressure sensor-based gas bubble detection for a drug delivery device, the drug delivery device comprising a fluid pathway, the fluid pathway comprising a reservoir configured to receive a fluid, a pump located downstream of the reservoir, and a fluid line located downstream of the pump, the method comprising: delivering the fluid from the reservoir to the fluid line using the pump; measuring, with a pressure sensor, a pressure in the fluid passageway downstream of the pump when delivering the fluid to the fluid line; receiving, with a microcontroller, the pressure measured in the fluid passageway downstream of the pump when delivering the fluid to the fluid line; determining, with the microcontroller, whether the fluid delivered to the fluid line includes gas bubbles based on the pressure measured in the fluid passageway downstream of the pump when the fluid is delivered to the fluid line; as well as An output device is controlled using the microcontroller to provide an indication associated with determining whether the fluid delivered to the fluid line includes gas bubbles.

12. The method according to claim 11, wherein: The pump includes a dosing chamber, wherein the pump is configured to cyclically: (i) draw from the reservoir while the dosing chamber is in fluid communication with the reservoir but not in fluid communication with the fluid line and (ii) fluidly connect the dosing chamber with the fluid line, and wherein the fluid is delivered to the fluid line when the dosing chamber is in fluid communication with the fluid line.

13. The method according to claim 12, further comprising: Prior to fluidly connecting the dosing chamber with the fluid line: measuring pressure in the fluid passage downstream of the pump using the pressure sensor; as well as A baseline pressure is determined based on the pressure measured in the fluid pathway downstream of the pump before fluidly connecting the dosing chamber with the fluid line, wherein whether the fluid delivered to the fluid line includes gas bubbles is determined based on the pressure measured in the fluid pathway downstream of the pump when the fluid is delivered to the fluid line and the baseline pressure.

14. The method according to claim 11, wherein: Determining whether the fluid delivered to the fluid line includes gas bubbles includes: comparing the pressure measured in the fluid passageway downstream of the pump when delivering the fluid to the fluid line to a threshold pressure; and In response to the pressure measured in the fluid passageway downstream of the pump satisfying the threshold pressure when the fluid is delivered to the fluid line, it is determined that the fluid delivered to the fluid line includes gas bubbles.

15. The method according to claim 11, wherein: Determining whether the fluid delivered to the fluid line includes gas bubbles includes: determining, based on the pressure measured in the fluid passageway downstream of the pump when delivering the fluid to the fluid line, a rate of change associated with the pressure measured in the fluid passageway downstream of the pump when delivering the fluid to the fluid line; comparing the rate of change associated with the pressure measured in the fluid passageway downstream of the pump when delivering the fluid to the fluid line to a threshold rate of change; and Responsive to the rate of change associated with the pressure measured in the fluid passageway downstream of the pump when delivering the fluid to the fluid line satisfying the threshold rate of change, it is determined that the fluid delivered to the fluid line includes gas bubbles.

16. The method according to claim 11, further comprising: receiving, with the microcontroller, a pressure associated with the fluid passage upstream of the pump; Using the microcontroller, based on the pressure associated with the fluid pathway upstream of the pump, the following items are determined: the pressure measured in the fluid pathway downstream of the pump when the fluid is delivered to the fluid pipeline; and at least one of the size of the fluid pathway, the volume of the gas bubbles included in the fluid delivered to the fluid pipeline, the volume of the fluid delivered to the fluid pipeline, or any combination thereof.

17. The method according to claim 11, wherein: Determining whether the fluid delivered to the fluid line includes gas bubbles includes: determining a pressure change over a period of time based on the pressure measured in the fluid passageway downstream of the pump while delivering the fluid to the fluid line; comparing the change in pressure over the period of time to a threshold change; and In response to the pressure change over the period of time satisfying the threshold change, it is determined that the fluid delivered to the fluid line during the period of time includes gas bubbles.

18. The method according to claim 17, further comprising: Using the microcontroller, at least one of the volume of the gas bubbles included in the fluid delivered to the fluid pipeline, the volume of the fluid delivered to the fluid pipeline, or any combination thereof is determined based on the pressure change over the period of time.

19. The method according to claim 11, further comprising: measuring, with the pressure sensor, another pressure in the fluid passage downstream of the pump during activation of the pump; receiving, with the microcontroller, from the pressure sensor, the other pressure measured in the fluid passage downstream of the pump during activation of the pump; as well as Based on a pressure measured in the fluid passage downstream of the pump during priming of the pump, it is determined whether the pump is fully primed.

20. A computer program product for pressure sensor-based gas bubble detection for a drug delivery device, the drug delivery device comprising a microcontroller, a pressure sensor, and a fluid pathway, the fluid pathway comprising a reservoir configured to receive a fluid, a pump located downstream of the reservoir, and a fluid line located downstream of the pump, the computer program product comprising at least one non-transitory computer readable medium, the at least one non-transitory computer readable medium comprising program instructions that, when executed by the microcontroller, cause the microcontroller to: controlling the pump to deliver the fluid from the reservoir to the fluid line; controlling the pressure sensor to measure pressure in the fluid passage downstream of the pump when delivering the fluid to the fluid line; as well as receiving from a pressure sensor the pressure measured in the fluid passageway downstream of the pump when delivering the fluid to the fluid line; determining whether the fluid delivered to the fluid line includes gas bubbles based on the pressure measured in the fluid passageway downstream of the pump when the fluid is delivered to the fluid line; as well as An output device is controlled to provide an indication associated with determining whether the fluid delivered to the fluid line includes gas bubbles.

Images