Insulin delivery management in closed-loop systems

Abstract

A control device for managing insulin delivery in a closed-loop system. The control device comprises a computation module. The computation module is configured to receive a target basal rate indicative of a rate of a target insulin delivery rate of an insulin pump and compute a supplemental basal rate if the target basal rate is greater than a rate threshold. The supplemental basal rate is sensibly equal to a difference between the target basal rate and the rate threshold. The control device also comprises an insulin management module. The insulin management module is configured to determine a recommendation value of a control parameter of the insulin pump. The recommendation value is based on the supplemental basal rate multiplied by a time period. The control device comprises a communication module. The communication module is configured to send the recommendation value to the insulin pump.

Description

Insulin delivery management in closed-loop systemsFIELD OF THE INVENTION

[0001] The present invention relates to the management of insulin delivery in closed-loop systems, specifically to a device and method for adjusting insulin delivery based on a target basal rate, a rate threshold, and a defined time period.BACKGROUND OF THE INVENTION

[0002] Closed-loop systems for insulin delivery have revolutionized diabetes management by automating the delivery of insulin in response to real-time glucose monitoring. These systems aim to maintain blood glucose levels within a target range by adjusting insulin delivery based on continuous feedback from glucose sensors. Despite the advancements in such systems, challenges persist in optimizing insulin delivery to accommodate the dynamic and individualized nature of glucose metabolism in patients with diabetes.

[0003] One of the primary difficulties in closed-loop insulin delivery is the accurate prediction and management of insulin requirements over time. Current systems may not adequately account for the variability in insulin absorption and action, leading to potential overdelivery or under delivery of insulin. Moreover, the rate at which insulin is delivered by the pump is often capped at a maximum threshold to prevent hypoglycemia, which can limit the system's ability to respond to sudden increases in insulin demand.

[0004] Additionally, the integration of various components within closed-loop systems, such as sensors, pumps, and control algorithms, presents complexities in ensuring reliable communication and coordinated action. Any disruption in this integration can compromise the system's ability to maintain glucose levels within the desired range, posing risks to the patient's health.

[0005] Therefore, there is a continuing demand for improvements in closed-loop insulin delivery systems that can provide more precise and adaptive management of insulin delivery, considering the fluctuating and personalized insulin requirements of patients, while also ensuring the safety and efficacy of the system.

[0006] The invention thus aims to answer at least partially the above presented technical problems.

[0007] BRIEF SUMMARY OF THE INVENTION

[0008] A control device for managing insulin delivery in a closed-loop system, the control device comprising:a computation module, the computation module being configured to:receive a target basal rate indicative of a rate of a target insulin delivery rate of an insulin pump;compute a supplemental basal rate if the target basal rate is greater than a rate threshold, the supplemental basal rate being sensibly equal to a difference between the target basal rate and the rate threshold;an insulin management module; the insulin management module being configured to determine a recommendation value of a control parameter of the insulin pump, the recommendation value being based on the supplemental basal rate multiplied by a time period; anda communication module, the communication module being configured to send the recommendation value to the insulin pump.

[0009] According to an embodiment, the control device is incorporated in an insulin pump.

[0010] The computation module's ability to receive a target basal rate indicative of a rate of a target insulin delivery rate of an insulin pump allows the control device to dynamically adjust to the user's insulin requirements as determined by the closed-loop system as such a target basal rate is determined by the closed-loop system. This ensures that the insulin delivery is tailored to the patient's current physiological state, potentially improving glycemic control.

[0011] The computation module's capability to compute a supplemental basal rate if the target basal rate is greater than a rate threshold addresses the issue of insulin pumps having a maximum basal rate limit. By calculating the supplemental basal rate, the control device can manage insulin delivery even when the user's insulin requirements exceed the pump's programmed rate threshold, thereby enhancing the safety and efficacy of insulin delivery.

[0012] The insulin management module's function to determine a recommendation value of a control parameter of the insulin pump, based on the supplemental basal rate multiplied by a time period, allows for precise control over insulin delivery. This can mitigate the risks associated with both overdelivery and underdelivery of insulin, which are common challenges in diabetes management.

[0013] In the context of the invention, the term "indicative" refers to a value or signal that serves as an instruction or guideline for the operation of the insulin pump. It represents a target or intended amount of insulin to be delivered, as opposed to the actual delivered quantity, which may vary due to potential inaccuracies or variations in the performance of the insulin pump. The indicative value is used by the control device to make decisions and manage the insulin delivery process, but it does not necessarily guarantee the precise quantity of insulin that will be delivered to the patient.

[0014] In the context of the present disclosure, the term "sensibly equal" is used to describe a value that is approximately equal to another value, within a tolerance of more or less 5%. This term acknowledges minor variations that may occur in practice, such as those due to measurement inaccuracies, system tolerances, or other factors that could cause a slight deviation from an exact numerical equivalence. Thus, when a value is described as being sensibly equal to another, it is understood that the value may be within 5% greater or less than the value to which it is being compared, while still achieving the intended purpose or function within the control device.

[0015] In the context of the present disclosure, the term "rate threshold" refers to the maximum basal rate that can be set on an insulin pump due to software limitations inherent to the pump's programming. This maximum basal rate acts as a cap on the insulin delivery rate, beyond which the pump's software will not permit the basal rate to be increased. The rate threshold is a predetermined value set within the pump's software to prevent excessive delivery of insulin, which could pose a risk to the patient. It is a safety feature designed to ensure that the insulin delivery stays within safe operational parameters as defined by the pump's capabilities and regulatory requirements. However, within the context of a closed-loop system, this rate threshold, while serving as a safety feature in other contexts, may be perceived as a limitation to optimized insulin delivery. This is because it may not allow the control device to closely match the user's fluctuating insulin requirements throughout the day. The closed-loop system aims to dynamically adjust insulin delivery to the user's current physiological state, but the rate threshold could restrict the system's ability to provide insulin doses that more precisely align with the user's immediate insulin requirements. Therefore, the rate threshold may impede the full potential of the closed-loop system to achieve tight glycemic control, which is central to the management of diabetes.

[0016] In the context of the present disclosure, the term "time period" refers to a duration. The time period may be a predetermined amount of time, which is a fixed duration established in advance, based on a schedule, a standard protocol, or a specific timing sequence. Alternatively, the time period may be a varying period of time, which can change or adjust in response to various factors, such as physiological signals, environmental conditions, or system feedback. This variability allows the time period to be dynamically adapted to the current requirements or states of the system or process it is associated with.

[0017] In the context of the present disclosure, the term "recommendation value of a control parameter of the insulin pump" corresponds to an insulin bolus, which is a dose of insulin infused by the pump in response to the recommendation from the control device. The recommendation value is calculated to be sensibly equal to the supplemental basal rate multiplied by a time period, effectively translating the supplemental basal rate into a discrete insulin bolus to be delivered at specific intervals. This bolus is intended to compensate for any difference between the target basal rate and the rate threshold, ensuring that the patient receives the appropriate amount of insulin as determined by the closed-loop system's algorithm. The communication module of the control device is responsible for sending this bolus recommendation to the insulin pump, which then executes the delivery of insulin accordingly.

[0018] According to an embodiment, the communication module is configured to send the recommendation value to the insulin pump only if no recommendation value has been sent within the preceding time period.

[0019] In the context of the present disclosure, the term "preceding time period" refers to the interval immediately before the current moment, extending backwards for the duration of a defined "time period." For instance, if the time period is specified as ten minutes, the preceding time period would be the last ten minutes leading up to the current time. This concept is particularly relevant when considering the timing of actions or events, such as the sending of recommendation values to an insulin pump, where it is imperative to ensure that such actions are not repeated more frequently than the defined time period.

[0020] Such a characteristic allows the control device to prevent the overdelivery of insulin by ensuring that recommendation values are not sent to the insulin pump more frequently than the defined time period. This is particularly beneficial in scenarios where the insulin pump is programmed to deliver boluses at regular intervals, as it mitigates the risk of stacking doses which could lead to hypoglycemia. By incorporating a control mechanism that restricts the communication module from sending recommendation values within the preceding time period, the control device ensures that insulin delivery is appropriately paced, aligning with the physiological requirements of the patient and the technical capabilities of the insulin pump. This feature is especially advantageous in closed-loop systems where insulin requirements are dynamically changing and the system is frequently computing new recommendation values. The control device thereby enhances the safety and efficacy of insulin delivery, providing a more reliable and patient-tailored diabetes management solution.

[0021] According to an embodiment, the time period is no less than five minutes and no more than thirty minutes.

[0022] The technical effects of a time period being no less than five minutes and no more than thirty minutes, are multifaceted. Firstly, this range ensures that the control device can provide frequent enough adjustments to the insulin delivery to respond to rapid changes in the patient's physiological state, such as fluctuations in blood glucose levels. A minimum of five minutes ensures that the system can react relatively quickly to such changes, which is particularly beneficial immediately after meals or during exercise when blood glucose levels can change more rapidly.

[0023] In a closed-loop system, recommendations for insulin delivery are often based on readings from a Continuous Glucose Monitor (CGM), which is a device that measures glucose levels in the interstitial fluid at regular intervals to provide a continuous assessment of glucose concentration in the body. To conserve energy and reduce the frequency of data transmission, which can be power-intensive, the CGM typically sends its readings to the control device every five minutes. This allows the closed-loop system to make informed decisions about insulin delivery while maintaining efficient power usage.

[0024] On the other hand, the maximum limit of thirty minutes prevents excessively delayed responses to changes in glucose levels, which could compromise glycemic control. By capping the time period at thirty minutes, the control device ensures that insulin delivery adjustments are made at intervals that are frequent enough to maintain tight glycemic control without causing large swings in glucose levels.

[0025] Furthermore, this range of time periods allows for flexibility in the control device's programming to accommodate different insulin pumps' capabilities and various patient-specific factors, such as insulin sensitivity and absorption rates. This flexibility is particularly advantageous in a closed-loop system where personalized diabetes management is a priority.

[0026] In summary, the technical effects include the ability to provide timely and responsive insulin delivery adjustments, the prevention of delayed insulin administration, and the flexibility to tailor the control device's operation to individual patient requirements and the technical specifications of various insulin pumps. These effects collectively contribute to the goal of achieving and maintaining tight glycemic control in a safe and patient-specific manner.

[0027] According to an embodiment, the time period is sensibly equal to ten minutes.

[0028] A time period sensibly equal to ten minutes allows the control device to establish a consistent and manageable interval for insulin delivery adjustments in the closed-loop system. This ten-minute interval aligns with the frequency at which the closed-loop system's algorithm typically makes recommendations, thereby ensuring that the control device's actions are synchronized with the system's computational cycle.

[0029] By setting the time period to a sensibly equal ten-minute duration, the control device can effectively mitigate the risks of overdelivery or underdelivery of insulin by providing a steady and predictable schedule for insulin administration. This interval also allows for a balance between responsive insulin delivery and the prevention of dose stacking, which could otherwise lead to hypoglycemia if boluses were delivered too frequently. The ten-minute time period thus contributes to the overall goal of achieving tight glycemic control by allowing the control device to adapt insulin delivery to the user's changing physiological requirements in a timely yet safe manner.

[0030] Given the CGM's data transmission every five minutes, a time period of ten minutes is a judicious choice as said time period not merely aligns with the CGM's data provision cycle but also offers a window that is sufficiently narrow to allow for timely insulin delivery adjustments, thereby facilitating rapid response to changes in glucose levels. Concurrently, it is broad enough to prevent the risk of dose stacking, which is a concern when insulin doses are infused too closely together. Thus, a ten-minute time period represents a good compromise between the desire for fast adjustments to the patient's insulin requirements and the mitigation of the risks associated with dose stacking. This balance is paramount in ensuring both the efficacy and safety of the closed-loop system's insulin delivery regimen.

[0031] Another technical effect of the time period being sensibly equal to ten minutes is to ensure that the resulting bolus calculation is greater than the minimum bolus that the pump is capable of delivering. When calculating over a five-minute period, there is a higher risk of encountering situations where the calculated bolus cannot be sent to the pump, which could lead to underdelivery of insulin. By using a ten-minute period, the control device increases the likelihood that the calculated bolus will exceed the pump's minimum delivery threshold, thereby ensuring more consistent and accurate insulin administration. This approach helps to maintain the intended insulin delivery profile and supports more precise glycemic control within the closed-loop system.

[0032] According to an embodiment, the rate threshold is determined based on the maximum basal rate that can be set on the insulin pump.

[0033] Such a characteristic allows the control device to fully utilize the potential of the insulin pump's capabilities. By aligning the rate threshold with the pump's maximum basal rate, the control device can ensure that insulin delivery is optimized within the technical constraints of the pump, thereby avoiding the unnecessary use of a recommendation value when it is not warranted. This approach allows for the precise management of insulin delivery, ensuring that the patient receives the appropriate amount of insulin as determined by the closed-loop system's algorithm, without exceeding the pump's designed safety limits. Consequently, this feature of the control device enhances the safety and efficacy of insulin delivery, as it prevents the risk of hypoglycemia that could result from overdelivery while also ensuring that the patient's insulin requirements are met even when they reach the upper limit of the pump's delivery capacity.

[0034] According to an embodiment, the rate threshold is equal to the maximum basal rate that can be set on the insulin pump. This rate threshold is a specific value that the insulin pump's software recognizes as the upper limit for basal insulin delivery. It is, for example, a safety measure to prevent the pump from administering an excessive amount of insulin, which could lead to hypoglycemia or other adverse effects. The rate threshold is determined by the technical specifications and safety protocols programmed into the insulin pump, and it represents the maximum rate at which the pump can deliver basal insulin over a given period of time. However, such an upper limit can be a limitation in a closed-loop context where the goal is to continuously and dynamically adjust insulin delivery to the patient's real-time physiological conditions. In scenarios where the patient's insulin requirements exceed the rate threshold, the closed-loop system may be unable to deliver the precise amount of insulin that is calculated as being ideal based on the patient's current glucose levels and other physiological parameters. This limitation can hinder the system's ability to maintain tight glycemic control, which is particularly detrimental for patients with fluctuating insulin sensitivities or those experiencing rapid changes in glucose levels. Therefore, while the rate threshold serves as a protective measure against overdelivery of insulin, it also presents a challenge for the closed-loop system to operate at its full potential in personalizing diabetes management.

[0035] According to an embodiment, the recommendation value of a control parameter of the insulin pump is sensibly equal to the supplemental basal rate multiplied by the time period.

[0036] This feature of the control device ensures that the insulin pump delivers a calculated dose of insulin that closely matches the supplemental basal rate over the defined time period. By multiplying the supplemental basal rate by the time period, the control device translates the continuous rate into a discrete bolus amount that can be administered by the insulin pump at the appropriate intervals. This method of calculating the recommendation value allows for the precise delivery of insulin, tailored to the patient's requirements as determined by the closed-loop system, while also respecting the technical limitations of the insulin pump. The term "sensibly equal" acknowledges minor variations that may occur in practice, such as those due to measurement inaccuracies or system tolerances, thereby providing a degree of flexibility in the control device's operation. This calculated approach to insulin delivery enhances the system's ability to maintain tight glycemic control and reduces the risk of hypoglycemia associated with insulin overdelivery.

[0037] In this case, to ensure that the target basal rate is achieved, the basal insulin rate of the insulin pump is set to the rate threshold. This setting acts as a baseline insulin delivery rate, which, when combined with the recommendation value, assures that the overall insulin delivery meets the target basal rate. The control device thus orchestrates the insulin delivery by utilizing the basal rate set at the rate threshold and supplementing it with the calculated recommendation value, which is based on the supplemental basal rate multiplied by the time period. This strategy allows the control device to circumvent the limitations imposed by the rate threshold, enabling the delivery of insulin doses that align with the dynamic insulin requirements of the patient as determined by the closed-loop system.

[0038] According to an embodiment, the recommendation value of a control parameter of the insulin pump is sensibly equal to the sum of the supplemental basal rate multiplied by the time period and the rate threshold multiplied by the time period.

[0039] This aspect of the control device ensures that the insulin pump delivers a calculated dose of insulin that is the sum of two components: the supplemental basal rate and the rate threshold, each multiplied by the same time period. This calculation reflects the target basal rate. By combining these two rates over the defined time period, the control device can provide a comprehensive insulin delivery strategy that aligns with the patient's insulin requirements as determined by the closed-loop system, while also adhering to the pump's maximum basal rate limit. This approach allows for the precise and safe delivery of insulin, ensuring that the patient's glycemic control is maintained within the desired range.

[0040] In instances where the control device determines that the target basal rate is to be met entirely by the recommendation value, the basal insulin rate of the insulin pump is set to zero. This ensures that the insulin delivery is achieved through the recommendation value alone, without any additional basal insulin being delivered by the pump. By setting the basal rate to zero in such scenarios, the control device prevents any basal insulin from being delivered, thereby relying on the precision of the recommendation value to achieve the desired target basal rate. This approach simplifies the insulin delivery process and can be advantageous in situations where the supplemental basal rate is high enough to fulfill the patient's insulin requirements without the contribution of a basal rate from the pump.

[0041] This approach offers a significant technical advantage by overcoming the limitations associated with the precision of basal rate delivery in certain insulin pumps. By relying solely on the recommendation value, which is delivered as a bolus, the control device can achieve a higher level of accuracy in insulin administration. Insulin pumps typically have different precision levels for basal rate delivery compared to bolus delivery. Basal rates are often delivered in small, frequent pulses, which can be subject to mechanical limitations and variations. On the other hand, bolus deliveries are generally more precise, as they involve a single, larger dose of insulin. By setting the basal insulin rate of the pump to zero and delivering the entire insulin requirement through the recommendation value (as a bolus), the control device capitalizes on the higher precision of bolus delivery. This method allows for more accurate dosing, particularly when small adjustments to insulin delivery are needed to maintain tight glycemic control. This strategy enhances the overall accuracy of insulin delivery in the closed-loop system, potentially leading to improved glycemic control and reduced risk of both hyper- and hypoglycemic events. It demonstrates how the control device can adapt to and overcome hardware limitations, ultimately providing a more refined and personalized approach to insulin therapy.

[0042] The invention also relates to a method for sending a recommendation value of a control parameter of an insulin pump in a closed-loop system, the method being implemented by a control device as described above and comprising:a step of receiving a target basal rate indicative of a rate of a target insulin delivery rate of an insulin pump;a step of computing a supplemental basal rate if the target basal rate is greater than a rate threshold, the supplemental basal rate being sensibly equal to a difference between the target basal rate and the rate threshold;a step of determining a recommendation value of a control parameter of the insulin pump, the recommendation value being based on the supplemental basal rate multiplied by a time period; anda step of sending the recommendation value to the insulin pump.

[0043] The embodiments, technical effects, and definitions disclosed herein with respect to the control device are also applicable to the method described herein. The method encompasses steps that fully utilize the functionalities and features of the control device described herein. Therefore, all embodiments, technical effects, and definitions pertaining to the device are equally applicable to the method. This ensures a comprehensive and unified understanding of both the control device and method aspects of the invention, facilitating the implementation and utilization of the disclosed technology across a range of applications.

[0044] According to an embodiment, the recommendation value is sent to the insulin pump if no recommendation value has been sent within the preceding time period.

[0045] According to an embodiment, the time period is no less than five minutes and no more than thirty minutes.

[0046] According to an embodiment, the time period is sensibly equal to ten minutes.

[0047] According to an embodiment, the rate threshold is determined based on a maximum basal rate that can be set on the insulin pump.

[0048] According to an embodiment, the method further comprises receiving a glucose level signal from a continuous glucose sensor, and wherein the recommendation value is determined based on the glucose level signal.

[0049] The inclusion of a glucose level signal from a continuous glucose sensor or CGM provides a substantial technical advantage by enabling real-time, data-driven adjustments to insulin delivery. This feature allows the control device to dynamically respond to the patient's immediate glycemic state, which is particularly beneficial for managing the rapid fluctuations in blood glucose levels that can occur throughout the day. By utilizing glucose level signals, the control device can calculate the recommendation value with a high degree of accuracy, ensuring that insulin delivery is closely aligned with the patient's current physiological requirements. This real-time adjustment capability enhances the safety and efficacy of the closed-loop system, reducing the risk of both hyperglycemia and hypoglycemia, and contributes to improved overall glycemic control. The continuous feedback provided by the glucose level signal ensures that the control device can make informed decisions, leading to a more personalized and adaptive approach to diabetes management.

[0050] According to an embodiment, the method further comprises adjusting the recommendation value based on a level of insulin on board (IOB).

[0051] The addition of adjusting the recommendation value based on the level of insulin on board (IOB) introduces a further technical advantage by enhancing the precision of insulin dosing. This adjustment considers the residual insulin activity from previous doses, which is a dynamic and patient-specific parameter. By considering the IOB, the control device can prevent insulin stacking, which is the accumulation of insulin activity that could lead to hypoglycemia if not properly managed. These adjustments contribute to a more nuanced and individualized insulin delivery strategy, which is central to the goal of personalized diabetes management and improved patient outcomes.

[0052] In the context of the present disclosure, the term "of insulin on board" (IOB) refers to the amount of insulin that has been previously administered and is still active within the body, affecting the patient's blood glucose levels. The IOB considers the fact that insulin, once delivered, continues to lower blood glucose levels for a period of time after administration. This period can vary depending on the type of insulin used, the individual's metabolism, and other physiological factors. The IOB is a dynamic parameter that decreases as the active insulin is metabolized and its glucose-lowering effect diminishes. Accurately accounting for the IOB is imperative in a closed-loop system to avoid the overdelivery of insulin, which could result in hypoglycemia if the cumulative effect of the active insulin exceeds the patient's current insulin requirements. The control device may adjust the recommendation value for insulin delivery by considering the IOB to ensure that the patient receives a safe and effective insulin dose that corresponds to their real-time physiological state.

[0053] The invention also relates to a computer program comprising instructions to cause the control device as described above to execute the steps of the method as described above.

[0054] The various non-incompatible aspects defined above can be combined.BRIEF DESCRIPTION OF THE DRAWINGS

[0055] Embodiments of the invention will be described below with reference to the drawings, described briefly below:

[0056] shows a control device according to one embodiment of the invention; and

[0057] shows a method for sending a recommendation value according to one embodiment of the invention.

[0058] DETAILED DESCRIPTION OF THE INVENTION

[0059] As shown in, the invention relates to a control device 30 for managing insulin delivery in a closed-loop system. The control device 30 comprises a computation module 32. The computation module 32 is configured to receive a target basal rate indicative of a rate of a target insulin delivery rate of an insulin pump 20 and compute a supplemental basal rate if the target basal rate is greater than a rate threshold, the supplemental basal rate being sensibly equal to a difference between the target basal rate and the rate threshold. The computation module's ability to receive a target basal rate indicative of a rate of a target insulin delivery rate of an insulin pump 20 allows the control device 30 to dynamically adjust to the user's insulin requirements as determined by the closed-loop system as such a target basal rate is determined by the closed-loop system. This ensures that the insulin delivery is tailored to the patient's current physiological state, potentially improving glycemic control. The computation module's capability to compute a supplemental basal rate if the target basal rate is greater than a rate threshold addresses the issue of insulin pumps 20 having a maximum basal rate limit. By calculating the supplemental basal rate, the control device 30 can manage insulin delivery even when the user's insulin requirements exceed the pump's programmed rate threshold, thereby enhancing the safety and efficacy of insulin delivery.

[0060] The rate threshold is determined based on the maximum basal rate that can be set on the insulin pump 20. Such a characteristic allows the control device 30 to fully utilize the potential of the insulin pump's capabilities. By aligning the rate threshold with the pump's maximum basal rate, the control device 30 can ensure that insulin delivery is optimized within the technical constraints of the pump, thereby avoiding the unnecessary use of a recommendation value when it is not warranted. This approach allows for the precise management of insulin delivery, ensuring that the patient receives the appropriate amount of insulin as determined by the closed-loop system's algorithm, without exceeding the pump's designed safety limits. Consequently, this feature of the control device 30 enhances the safety and efficacy of insulin delivery, as it prevents the risk of hypoglycemia that could result from overdelivery while also ensuring that the patient's insulin requirements are met even when they reach the upper limit of the pump's delivery capacity. Furthermore, the rate threshold is equal to the maximum basal rate that can be set on the insulin pump 20. This rate threshold is a specific value that the insulin pump's software recognizes as the upper limit for basal insulin delivery. It is a safety measure to prevent the pump from administering an excessive amount of insulin, which could lead to hypoglycemia or other adverse effects. The rate threshold is determined by the technical specifications and safety protocols programmed into the insulin pump 20, and it represents the maximum rate at which the pump can deliver basal insulin over a given period of time. However, such an upper limit can be a limitation in a closed-loop context where the goal is to continuously and dynamically adjust insulin delivery to the patient's real-time physiological conditions. In scenarios where the patient's insulin requirements exceed the rate threshold, the closed-loop system may be unable to deliver the precise amount of insulin that is calculated as being ideal based on the patient's current glucose levels and other physiological parameters. This limitation can hinder the system's ability to maintain tight glycemic control, which is particularly detrimental for patients with fluctuating insulin sensitivities or those experiencing rapid changes in glucose levels. Therefore, while the rate threshold serves as a protective measure against overdelivery of insulin, it also presents a challenge for the closed-loop system to operate at its full potential in personalizing diabetes management.

[0061] The control device 30 also comprises an insulin management module 34. The insulin management module 34 is configured to determine a recommendation value of a control parameter of the insulin pump 20. The recommendation value is based on the supplemental basal rate multiplied by a time period, the time period being no less than five minutes, no more than thirty minutes and preferably sensibly equal to ten minutes. The insulin management module's function to determine a recommendation value of a control parameter of the insulin pump 20, based on the supplemental basal rate multiplied by a time period, allows for precise control over insulin delivery. This can mitigate the risks associated with both overdelivery and under delivery of insulin, which are common challenges in diabetes management. The technical effects of a time period being no less than five minutes and no more than thirty minutes, are multifaceted. Firstly, this range ensures that the control device 30 can provide frequent enough adjustments to the insulin delivery to respond to rapid changes in the patient's physiological state, such as fluctuations in blood glucose levels. A minimum of five minutes ensures that the system can react relatively quickly to such changes, which is particularly beneficial immediately after meals or during exercise when blood glucose levels can change more rapidly. In a closed-loop system, recommendations for insulin delivery are often based on readings from a Continuous Glucose Monitor (CGM), which is a device that measures glucose levels in the interstitial fluid at regular intervals to provide a continuous assessment of glucose concentration in the body. To conserve energy and reduce the frequency of data transmission, which can be power-intensive, the CGM typically sends its readings to the control device 30 every five minutes. This allows the closed-loop system to make informed decisions about insulin delivery while maintaining efficient power usage. On the other hand, the maximum limit of thirty minutes prevents excessively delayed responses to changes in glucose levels, which could compromise glycemic control. By capping the time period at thirty minutes, the control device 30 ensures that insulin delivery adjustments are made at intervals that are frequent enough to maintain tight glycemic control without causing large swings in glucose levels. Furthermore, this range of time periods allows for flexibility in the control device's programming to accommodate different insulin pump s' capabilities and various patient-specific factors, such as insulin sensitivity and absorption rates. This flexibility is particularly advantageous in a closed-loop system where personalized diabetes management is a priority. In summary, the technical effects include the ability to provide timely and responsive insulin delivery adjustments, the prevention of delayed insulin administration, and the flexibility to tailor the control device's operation to individual patient requirements and the technical specifications of various insulin pumps 20. These effects collectively contribute to the goal of achieving and maintaining tight glycemic control in a safe and patient-specific manner.

[0062] A time period sensibly equal to ten minutes allows the control device 30 to establish a consistent and manageable interval for insulin delivery adjustments in the closed-loop system. This ten-minute interval aligns with the frequency at which the closed-loop system's algorithm typically makes recommendations, thereby ensuring that the control device's actions are synchronized with the system's computational cycle. By setting the time period to a sensibly equal ten-minute duration, the control device 30 can effectively mitigate the risks of overdelivery or underdelivery of insulin by providing a steady and predictable schedule for insulin administration. This interval also allows for a balance between responsive insulin delivery and the prevention of dose stacking, which could otherwise lead to hypoglycemia if boluses were delivered too frequently. The ten-minute time period thus contributes to the overall goal of achieving tight glycemic control by allowing the control device 30 to adapt insulin delivery to the user's changing physiological requirements in a timely yet safe manner. Given the CGM's data transmission every five minutes, a time period of ten minutes is a judicious choice as said time period not merely aligns with the CGM's data provision cycle but also offers a window that is sufficiently narrow to allow for timely insulin delivery adjustments, thereby facilitating rapid response to changes in glucose levels. Concurrently, it is broad enough to prevent the risk of dose stacking, which is a concern when insulin doses are infused too closely together. Thus, a ten-minute time period represents a good compromise between the desire for fast adjustments to the patient's insulin requirements and the mitigation of the risks associated with dose stacking. This balance is paramount in ensuring both the efficacy and safety of the closed-loop system's insulin delivery regimen. Another technical effect of the time period being sensibly equal to ten minutes is to ensure that the resulting bolus calculation is greater than the minimum bolus that the pump is capable of delivering. When calculating over a five-minute period, there is a higher risk of encountering situations where the calculated bolus cannot be sent to the pump, which could lead to underdelivery of insulin. By using a ten-minute period, the control device 30 increases the likelihood that the calculated bolus will exceed the pump's minimum delivery threshold, thereby ensuring more consistent and accurate insulin administration. This approach helps to maintain the intended insulin delivery profile and supports more precise glycemic control within the closed-loop system.

[0063] The control device 30 also comprises a communication module 36. The communication module 36 is configured to send the recommendation value to the insulin pump 20. The communication module 36 is configured to send the recommendation value to the insulin pump 20 only if no recommendation value has been sent within the preceding time period. Such a characteristic allows the control device 30 to prevent the overdelivery of insulin by ensuring that recommendation values are not sent to the insulin pump 20 more frequently than the defined time period. This is particularly beneficial in scenarios where the insulin pump 20 is programmed to deliver boluses at regular intervals, as it mitigates the risk of stacking doses which could lead to hypoglycemia. By incorporating a control mechanism that restricts the communication module 36 from sending recommendation values within the preceding time period, the control device 30 ensures that insulin delivery is appropriately paced, aligning with the physiological requirements of the patient and the technical capabilities of the insulin pump 20. This feature is especially advantageous in closed-loop systems where insulin requirements are dynamically changing and the system is frequently computing new recommendation values. The control device 30 thereby enhances the safety and efficacy of insulin delivery, providing a more reliable and patient-tailored diabetes management solution.

[0064] According to a first embodiment, the recommendation value of a control parameter of the insulin pump 20 is sensibly equal to the supplemental basal rate multiplied by the time period. This feature of the control device 30 ensures that the insulin pump 20 delivers a calculated dose of insulin that closely matches the supplemental basal rate over the defined time period. By multiplying the supplemental basal rate by the time period, the control device 30 translates the continuous rate into a discrete bolus amount that can be administered by the insulin pump 20 at the appropriate intervals. This method of calculating the recommendation value allows for the precise delivery of insulin, tailored to the patient's requirements as determined by the closed-loop system, while also respecting the technical limitations of the insulin pump 20. The term "sensibly equal" acknowledges minor variations that may occur in practice, such as those due to measurement inaccuracies or system tolerances, thereby providing a degree of flexibility in the control device's operation. This calculated approach to insulin delivery enhances the system's ability to maintain tight glycemic control and reduces the risk of hypoglycemia associated with insulin overdelivery. In this case, to ensure that the target basal rate is achieved, the basal insulin rate of the insulin pump 20 is set to the rate threshold. This setting acts as a baseline insulin delivery rate, which, when combined with the recommendation value, assures that the overall insulin delivery meets the target basal rate. The control device 30 thus orchestrates the insulin delivery by utilizing the basal rate set at the rate threshold and supplementing it with the calculated recommendation value, which is based on the supplemental basal rate multiplied by the time period. This strategy allows the control device 30 to circumvent the limitations imposed by the rate threshold, enabling the delivery of insulin doses that align with the dynamic insulin requirements of the patient as determined by the closed-loop system.

[0065] According to a second embodiment, the recommendation value of a control parameter of the insulin pump 20 is sensibly equal to the sum of the supplemental basal rate multiplied by the time period and the rate threshold multiplied by the time period. This aspect of the control device 30 ensures that the insulin pump 20 delivers a calculated dose of insulin that is the sum of two components: the supplemental basal rate and the rate threshold, each multiplied by the same time period. This calculation reflects the target basal rate. By combining these two rates over the defined time period, the control device 30 can provide a comprehensive insulin delivery strategy that aligns with the patient's insulin requirements as determined by the closed-loop system, while also adhering to the pump's maximum basal rate limit. This approach allows for the precise and safe delivery of insulin, ensuring that the patient's glycemic control is maintained within the desired range. In instances where the control device 30 determines that the target basal rate is to be met entirely by the recommendation value, the basal insulin rate of the insulin pump 20 is set to zero. This ensures that the insulin delivery is achieved through the recommendation value alone, without any additional basal insulin being delivered by the pump. By setting the basal rate to zero in such scenarios, the control device 30 prevents any basal insulin from being delivered, thereby relying on the precision of the recommendation value to achieve the desired target basal rate. This approach simplifies the insulin delivery process and can be advantageous in situations where the supplemental basal rate is high enough to fulfill the patient's insulin requirements without the contribution of a basal rate from the pump. This approach offers a significant technical advantage by overcoming the limitations associated with the precision of basal rate delivery in certain insulin pumps 20. By relying solely on the recommendation value, which is delivered as a bolus, the control device 30 can achieve a higher level of accuracy in insulin administration. Insulin pumps 20 typically have different precision levels for basal rate delivery compared to bolus delivery. Basal rates are often delivered in small, frequent pulses, which can be subject to mechanical limitations and variations. On the other hand, bolus deliveries are generally more precise, as they involve a single, larger dose of insulin. By setting the basal insulin rate of the pump to zero and delivering the entire insulin requirement through the recommendation value (as a bolus), the control device 30 capitalizes on the higher precision of bolus delivery. This method allows for more accurate dosing, particularly when small adjustments to insulin delivery are needed to maintain tight glycemic control. This strategy enhances the overall accuracy of insulin delivery in the closed-loop system, potentially leading to improved glycemic control and reduced risk of both hyper- and hypoglycemic events. It demonstrates how the control device 30 can adapt to and overcome hardware limitations, ultimately providing a more refined and personalized approach to insulin therapy.

[0066] The invention also relates to a method for sending a recommendation value of a control parameter of an insulin pump 20 in a closed-loop system. The method is implemented by a control device 30 as described above and comprises:a step of receiving 50 a target basal rate indicative of a rate of a target insulin delivery rate of an insulin pump 20;a step of computing 52 a supplemental basal rate if the target basal rate is greater than a rate threshold determined based on a maximum basal rate that can be set on the insulin pump 20, the supplemental basal rate being sensibly equal to a difference between the target basal rate and the rate threshold;a step of determining 54 a recommendation value of a control parameter of the insulin pump 20, the recommendation value being based on the supplemental basal rate multiplied by a time period being no less than five minutes, no more than thirty minutes and preferably sensibly equal to ten minutes; anda step of sending 56 the recommendation value to the insulin pump 20, wherein the recommendation value is sent to the insulin pump 20 if no recommendation value has been sent within the preceding time period.

[0067] The embodiments, technical effects, and definitions disclosed herein with respect to the control device 30 are also applicable to the method described herein. The method encompasses steps that fully utilize the functionalities and features of the control device 30 described herein. Therefore, all embodiments, technical effects, and definitions pertaining to the device are equally applicable to the method. This ensures a comprehensive and unified understanding of both the control device 30 and method aspects of the invention, facilitating the implementation and utilization of the disclosed technology across a range of applications.

[0068] The method further comprises receiving a glucose level signal from a continuous glucose sensor 12, and wherein the recommendation value is determined based on the glucose level signal. The inclusion of a glucose level signal from a continuous glucose sensor or CGM provides a substantial technical advantage by enabling real-time, data-driven adjustments to insulin delivery. This feature allows the control device 30 to dynamically respond to the patient's immediate glycemic state, which is particularly beneficial for managing the rapid fluctuations in blood glucose levels that can occur throughout the day. By utilizing glucose level signals, the control device 30 can calculate the recommendation value with a high degree of accuracy, ensuring that insulin delivery is closely aligned with the patient's current physiological requirements. This real-time adjustment capability enhances the safety and efficacy of the closed-loop system, reducing the risk of both hyperglycemia and hypoglycemia, and contributes to improved overall glycemic control. The continuous feedback provided by the glucose level signal ensures that the control device 30 can make informed decisions, leading to a more personalized and adaptive approach to diabetes management.

[0069] The method further comprises adjusting the recommendation value based on a level of insulin on board (IOB). The addition of adjusting the recommendation value based on the level of insulin on board (IOB) introduces a further technical advantage by enhancing the precision of insulin dosing. This adjustment considers the residual insulin activity from previous doses, which is a dynamic and patient-specific parameter. By considering the IOB, the control device 30 can prevent insulin stacking, which is the accumulation of insulin activity that could lead to hypoglycemia if not properly managed. These adjustments contribute to a more nuanced and individualized insulin delivery strategy, which is central to the goal of personalized diabetes management and improved patient outcomes.

[0070] The invention also relates to a computer program comprising instructions to cause the control device 30 as described above to execute the steps of the method described above.

[0071] The invention also relates to a system 10 comprising a CGM 12, an insulin pump 20 and a control device 30.

[0072] The present disclosure pertains to a control device 30 and method for managing insulin delivery in closed-loop systems. The disclosed technology is particularly applicable in the field of diabetes management, where it can be used to optimize the delivery of insulin in response to real-time glucose monitoring. The control device 30 and method disclosed herein are designed to adapt insulin quantities recommended by an algorithm to the technical specification of insulin pumps 20, addressing the challenges of overdelivery and underdelivery of insulin, and the limitations imposed by the maximum basal rate that can be set on an insulin pump 20.

[0073] The disclosed technology can be applied in the medical industry, specifically in the development and operation of insulin pumps 20 and closed-loop systems for diabetes management. It can be used by manufacturers of insulin pumps 20 and other medical devices, healthcare providers, and researchers in the field of diabetes management. The technology can also be integrated into existing closed-loop systems to enhance their performance and safety.

[0074] While exemplary embodiments of the invention have been described, it will be understood by those skilled in the art that various changes, omissions and / or additions may be made, and equivalents may be substituted for elements thereof without departing from the spirit and scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the scope thereof. Therefore, it is intended that the invention is not limited to the particular embodiments disclosed for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims. Moreover, unless specifically stated any use of the terms first, second, etc. do not denote any order or importance, but rather the terms first, second, etc. are used to distinguish one element from another.

Claims

A control device (30) for managing insulin delivery in a closed-loop system, the control device (30) comprising:a computation module (32), the computation module (32) being configured to:receive a target basal rate indicative of a rate of a target insulin delivery rate of an insulin pump (20);compute a supplemental basal rate if the target basal rate is greater than a rate threshold, the supplemental basal rate being sensibly equal to a difference between the target basal rate and the rate threshold;an insulin management module (34); the insulin management module (34) being configured to determine a recommendation value of a control parameter of the insulin pump (20), the recommendation value being based on the supplemental basal rate multiplied by a time period; anda communication module (36), the communication module (36) being configured to send the recommendation value to the insulin pump (20),wherein the communication module (36) is configured to send the recommendation value to the insulin pump (20) only if no recommendation value has been sent within the preceding time period,wherein the rate threshold refers to the maximum basal rate that can be set on an insulin pump due to software limitations inherent to the pump's programming,wherein recommendation value of a control parameter of the insulin pump corresponds to an insulin bolus.The control device (30) according to claim 1, wherein the time period is no less than five minutes and no more than thirty minutes.The control device (30) according to claim 2, wherein the time period is sensibly equal to ten minutes.The control device (30) according to any of the claims 1 to 3, wherein the rate threshold is determined based on the maximum basal rate that can be set on the insulin pump (20).The control device (30) according to any of the claims 1 to 4, wherein the recommendation value of a control parameter of the insulin pump (20) is sensibly equal to the supplemental basal rate multiplied by the time period.The control device (30) according to any of the claims 1 to 4, wherein the recommendation value of a control parameter of the insulin pump (20) is sensibly equal to the sum of the supplemental basal rate multiplied by the time period and the rate threshold multiplied by the time period.A method for sending a recommendation value of a control parameter of an insulin pump (20) in a closed-loop system, the method being implemented by a control device (30) according to claim 1 and comprising:a step of receiving (50) a target basal rate indicative of a rate of a target insulin delivery rate of an insulin pump (20);a step of computing (52) a supplemental basal rate if the target basal rate is greater than a rate threshold, the supplemental basal rate being sensibly equal to a difference between the target basal rate and the rate threshold;a step of determining (54) a recommendation value of a control parameter of the insulin pump (20), the recommendation value being based on the supplemental basal rate multiplied by a time period; anda step of sending (56) the recommendation value to the insulin pump (20),wherein the recommendation value is sent to the insulin pump (20) if no recommendation value has been sent within the preceding time period,wherein the rate threshold refers to the maximum basal rate that can be set on an insulin pump due to software limitations inherent to the pump's programming,wherein recommendation value of a control parameter of the insulin pump corresponds to an insulin bolus.The method according to claim 7, wherein the time period is no less than five minutes and no more than thirty minutes.The method according to claim 8, wherein the time period is sensibly equal to ten minutes.The method according to any of the claims 7 to 9, wherein the rate threshold is determined based on a maximum basal rate that can be set on the insulin pump (20).The method according to any of the claims 7 to 10, further comprising receiving a glucose level signal from a continuous glucose sensor (12), and wherein the recommendation value is determined based on the glucose level signal.The method according to any of the claims 7 to 11, further comprising adjusting the recommendation value based on a level of insulin on board (IOB).A computer program comprising instructions to cause the control device (30) of claim 1 to execute the steps of the method of claim 6.

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