HK1119803A

HK1119803A - A system and method providing for user intervention in a diabetes control arrangement

Info

Publication number: HK1119803A
Application number: HK08111781.2A
Authority: HK
Inventors: Steven Bousamra; Siva Chittajallu; Paul Galley; Ajay Thukral; Robin Wagner; Stefan Weinert
Original assignee: F. Hoffmann-La Roche Ag
Priority date: 2005-06-06
Filing date: 2006-06-03
Publication date: 2009-03-13

Description

System and method for providing user intervention in a diabetes control arrangement

Technical Field

The present invention relates generally to diabetes control devices, and more particularly to systems and methods for providing user intervention in such diabetes control devices.

Background

Conventional diabetes control devices may be or may include fully or semi-closed loop systems operable to determine and deliver insulin to a user. It is desirable to allow user intervention in such systems to provide fail-safe operation.

Disclosure of Invention

The invention may comprise one or more of the features recited in the appended claims, and/or one or more of the following features and combinations thereof. A system for providing user intervention in a diabetes control arrangement may comprise: means responsive to user selection thereof for generating one of the first and second user intervention signals, and a processor executing an insulin delivery algorithm forming part of the diabetes control arrangement. The processor may include one of an intervention insulin quantity (intervention insulin quantity) and an intervention carbohydrate quantity in executing the insulin delivery algorithm in response to the first user intervention signal. The processor may exclude one of the intervention insulin quantity and the intervention carbohydrate quantity from executing the insulin delivery algorithm in response to the second user intervention signal.

The processor may be configured to continuously and uninterruptedly execute the insulin delivery algorithm regardless of whether the first or second user intervention signal is generated.

The system may further include means for providing one of the intervention insulin quantity and the intervention carbohydrate quantity to the processor.

The processor may be responsive to the first user intervention signal to process the intervention insulin quantity by adding the intervention insulin quantity to a current insulin bolus (bolus) quantity. The processor may also be responsive to the first user intervention signal to command administration of a combination of the intervention insulin quantity and the current insulin bolus quantity to the user. The current insulin bolus amount may be a positive insulin bolus amount. Alternatively, the current insulin bolus amount may be a zero-value insulin bolus amount.

The processor may be responsive to the first user intervention signal to process the intervention carbohydrate amount by modifying the blood glucose target according to the intervention carbohydrate amount.

The system may also include a database having stored therein insulin delivery and intervention carbohydrate information. The processor may input one of the intervention insulin quantity and the intervention carbohydrate quantity into the database in response to either of the first and second user intervention signals.

The processor is operable to wait a delay time before including one of the intervention insulin quantity and the intervention carbohydrate quantity in the execution of the insulin delivery algorithm.

A method of allowing user intervention in a diabetes control arrangement may comprise: executing an insulin delivery algorithm, the insulin delivery algorithm forming part of the diabetes control device; monitoring the first and second user intervention mechanisms; in response to a user selection of the first user intervention mechanism, including one of an intervention insulin amount and an intervention carbohydrate amount in executing the insulin delivery algorithm; and excluding one of the intervention insulin quantity and the intervention carbohydrate quantity from executing the insulin delivery algorithm in response to the user selecting the second user intervention mechanism.

The method may further include receiving one of an intervention insulin amount and an intervention carbohydrate amount.

The method may further include inputting one of the intervention insulin quantity and the intervention carbohydrate quantity into the database in response to a user selecting either of the first and second user intervention mechanisms. The method may further include date and time stamping (stamping) the one of the intervention insulin quantity and the intervention carbohydrate quantity prior to entering the one of the intervention insulin quantity and the intervention carbohydrate quantity into the database.

The method may further include waiting a delay time after the user selects the first user intervention mechanism and before including one of the intervention insulin quantity and the intervention carbohydrate quantity in the execution of the insulin delivery algorithm.

A system for providing user intervention in a medical control arrangement may comprise a first user intervention mechanism responsive to user selection thereof for generating a first user intervention signal, a second user intervention mechanism responsive to user selection thereof for generating a second user intervention signal, and a processor for executing a drug delivery algorithm forming part of the medical control arrangement. The processor may be responsive to the first user intervention signal to include the intervention drug quantity in the execution of the drug delivery algorithm. The processor may be responsive to the second user intervention signal to exclude the intervention drug quantity from execution of the drug delivery algorithm.

The system may further include means for receiving an intervention drug quantity.

The medical control device may be a diabetes control device, the drug delivery algorithm may be an insulin delivery algorithm, and the intervention drug quantity may be an intervention insulin quantity. The processor may be responsive to the first user intervention signal to include the intervention insulin quantity in the execution of the insulin delivery algorithm by adding the intervention insulin quantity to the current insulin bolus quantity. The processor may also be responsive to the first user intervention signal to command administration of the combination of the intervention insulin quantity and the current insulin bolus quantity to the user.

The system may also include a database having drug delivery information stored therein. The processor may be responsive to either of the first and second user intervention signals to input the intervention drug quantity into the database. The processor may be configured to date and time stamp the intervention drug quantity prior to entry into the database.

The processor is operable to wait for a delay time before including the intervention drug quantity in the execution of the insulin delivery algorithm.

A method of allowing user intervention in a medical control device may comprise: executing a drug delivery algorithm, the drug delivery algorithm forming part of the medical control device; monitoring the first and second user intervention mechanisms; including an intervention drug quantity in the execution of the drug delivery algorithm in response to a user selection of the first user intervention mechanism; and excluding the intervention drug quantity from execution of the drug delivery algorithm in response to user selection of the second user intervention mechanism.

The method may further include receiving an intervention drug quantity.

The method further includes entering the intervention drug quantity into a database in response to a user selecting either of the first and second user intervention mechanisms. The method may further include date and time stamping the intervention drug quantity prior to entering the intervention drug quantity into the database.

The method may further include waiting a delay time after the user selects the first user intervention mechanism and before including the intervention drug quantity in the execution of the drug delivery algorithm.

The medical control device may be a diabetes control device, the drug delivery algorithm may be an insulin delivery algorithm, and the intervention drug quantity may be an insulin intervention quantity.

A system for providing user intervention in a medical control device may comprise a first user intervention mechanism responsive to user selection thereof for generating a first user intervention signal, a second user intervention mechanism responsive to user selection thereof for generating a second user intervention signal, and a processor for executing a drug delivery algorithm forming part of the medical control device. The processor may be responsive to the first user intervention signal to include an intervention therapy value in executing the drug delivery algorithm. The processor may be responsive to the second user intervention signal to exclude the intervention therapy value from execution of the drug delivery algorithm.

The system may also include means for receiving an intervention therapy value.

The medical control device may be a diabetes control device, the drug delivery algorithm may be an insulin delivery algorithm, and the intervention therapy value may be an intervention insulin quantity. Alternatively, the intervention therapy value may be an intervention carbohydrate amount corresponding to a quantity of carbohydrates recently intervened by the user. In the former case, the processor may be responsive to the first user intervention signal to include the intervention insulin quantity in the execution of the insulin delivery algorithm by adding the intervention insulin quantity to the current insulin bolus quantity. The current insulin bolus quantity may have a value greater than or equal to zero. In the latter case, the processor may be responsive to the first user intervention signal to include the intervention carbohydrate amount in the execution of the insulin delivery algorithm by modifying the blood glucose target as a function of the intervention carbohydrate amount.

The system may also include a database having treatment value information stored therein. The processor may be responsive to either of the first and second user intervention signals to input the intervention therapy value into the database. The processor may be configured to date and time stamp the intervention therapy value prior to entering the intervention therapy value into the database.

The processor is operable to wait for a delay time before including the intervention therapy value in the execution of the drug delivery algorithm.

The processor may be configured to continuously and uninterruptedly execute the drug delivery algorithm regardless of whether the first or second user intervention signal is generated.

A method of allowing user intervention in a medical control device may comprise: executing a drug delivery algorithm, the drug delivery algorithm forming part of the medical control device; monitoring the first and second user intervention mechanisms; in response to a user selection of a first user intervention mechanism, including an intervention therapy value in the execution of the drug delivery algorithm; and excluding the intervention therapy value from execution of the drug delivery algorithm in response to the user selecting the second user intervention mechanism.

The method may also include receiving an intervention therapy value.

The method may further include entering the intervention therapy value into the database in response to a user selecting either of the first and second user intervention mechanisms. The method may further include date and time stamping the intervention therapy value prior to entering the intervention therapy value into the database.

The method may further include waiting a delay time after selecting the first user intervention mechanism and before including the intervention therapy value in executing the drug delivery algorithm.

The medical control device may be a diabetes control device, the drug delivery algorithm may be an insulin delivery algorithm, and the intervention therapy value may be an insulin intervention quantity. Alternatively, the intervention therapy value may be an intervention carbohydrate amount corresponding to a quantity of carbohydrates recently intervened by the user.

Drawings

Fig. 1 is a block diagram of one exemplary embodiment of a system for providing user intervention in a controlled insulin delivery device.

FIG. 2 is a flow chart of one exemplary embodiment of a software algorithm for providing user intervention in a controlled insulin delivery system.

FIG. 3 is a flow diagram of one exemplary embodiment of an intervention insulin quantity processing routine invoked by the algorithm of FIG. 2.

FIG. 4 is a flow diagram of one exemplary embodiment of an intervention carbohydrate quantity processing routine invoked by the algorithm of FIG. 2.

DETAILED DESCRIPTION OF EMBODIMENT (S) OF INVENTION

For the purposes of promoting an understanding of the principles of the invention, reference will now be made to a number of exemplary embodiments illustrated in the drawings and specific language will be used to describe the same.

Referring now to FIG. 1, a block diagram of one exemplary embodiment of a system 10 for providing user intervention in a diabetes control arrangement is shown. In the illustrated embodiment, the system 10 includes an electronic device 12 having a processor 14 in data communication with a memory unit 16, an input device 18, a display 20, and a communication input/output unit 24. The electronic device 12 may be provided in the form of a general purpose computer, a central server, a Personal Computer (PC), a laptop or notebook computer, a Personal Data Assistant (PDA) or other handheld device, an external infusion pump, or the like. Electronic device 12 may be configured to operate in accordance with one or more conventional operating systems, including for example and without limitation windows, linux, and palm OS, and may be configured to process data in accordance with one or more conventional Internet protocols, such as for example and without limitation NetBios, TCP/IP, and AppleTalk. In any case, the electronic device 12 forms part of a closed-loop or semi-closed-loop diabetes control system, examples of which are described below. In an exemplary embodiment, processor 14 is microprocessor-based, although processor 14 may alternatively be formed from one or more general purpose and/or special purpose circuits and may operate as described below. In the exemplary embodiment, storage unit 16 includes sufficient capacity to store data, one or more software algorithms executable by processor 14, and other data. The storage unit 16 may include one or more conventional memories or other data storage devices.

The input device 18 may be used to input and/or modify data in a conventional manner. In the exemplary embodiment, a display 20 is also included for viewing information relating to the operation of device 12 and/or system 10. Such a display may be a conventional display device including, for example and without limitation, a Light Emitting Diode (LED) display, a liquid crystal display, a Cathode Ray Tube (CRT) display, and the like. Alternatively or additionally, the display 20 may be or include an audible display configured to communicate information to a user or third party via one or more coded patterns, vibrations, synthesized voice responses, or the like. Alternatively or additionally, the display 20 may be or include one or more tactile indicators configured to display tactile information discernible by a user or a third party.

In one embodiment, the input device 18 may be or include a conventional keyboard or keypad for entering alphanumeric data into the processor 14. Such a keyboard or keypad may include one or more keys or buttons configured with one or more tactile indicators to allow users with poor eyesight to find and select the appropriate one or more keys, and/or to allow users to find the appropriate one or more keys under poor lighting conditions. Alternatively or additionally, the input device 18 may be or include a conventional mouse or other conventional pointing device for selecting information presented on the display 20. Alternatively or additionally, the input device 18 may include a display 20 configured as a Graphical User Interface (GUI). In this embodiment, the display 20 may include one or more selectable inputs that the user may select by touching the appropriate portion of the display 20 using the appropriate implement. Alternatively or additionally, input device 18 may include a plurality of switches or buttons that may be activated by a user to select corresponding operating features of device 12 and/or system 10. Alternatively or additionally, the input device 18 may be or include a voice activated circuit that provides corresponding input data to the processor 14 in response to voice commands. In any case, the input device 18 and/or the display 20 may be included in the electronic device 12 or separate from the electronic device 12, as indicated by dashed lines 22A and 22B.

In some embodiments, system 10 may include a plurality (N) of medical devices 26₁-26_NWhere N may be any positive integer. In these embodiments, one or more medical devices 26₁-26_NEither of which may be implanted within the body of the user, externally coupled to the body of the user (such as an infusion pump, for example), or separate from the body of the user. Alternatively or additionally, one or more medical devices 26₁-26_NMay be mounted to electronic device 12 and/or form part of electronic device 12. In the exemplary embodiment, the plurality of medical devices 26₁-26_NEach of which isIs configured to communicate via a corresponding number of wireless communication lines 28₁-28_NOne of which communicates wirelessly with the communication I/O unit 24 of the electronic device. The wireless communication may be unidirectional or bidirectional.

The form of wireless communication used may include, but should not be limited to, Radio Frequency (RF) communication, Infrared (IR) communication, RFID (inductive coupling) communication, acoustic communication, (capacitive signaling over a conductor), (galvanic signaling) over a conductor, and the like. In any such case, the electronic device 12 and the plurality of medical devices 26₁-26_NEach of which includes a wireless communication circuit 18 for conducting such a wireless communication₁May further include, as appropriate. Alternatively or additionally, one or more medical devices 26₁-26_NMay be configured to communicate with electronic device 12 via one or more conventional hardwired connections with electronic device 12. One or more medical devices 26₁-26_NEach of which may include any one or more conventional processing units, conventional input/output circuits and/or devices, and one or more suitable data and/or program storage devices.

The system shown in fig. 1 is or forms part of a conventional closed-loop or semi-closed-loop diabetes control device. In this regard, the system 10 includes a delivery mechanism for delivering a controlled amount of a drug; e.g., insulin, glucagon (glucagons), incretins (incretins), etc., and/or include providing alternative actionable recommendations to the user via the display 20, e.g., ingestion of carbohydrates, exercise, etc. The system 10 may be provided in any of a variety of conventional configurations, and some examples of such configurations will now be described. However, it will be understood that the following examples are provided for illustrative purposes only and should not be construed as limiting in any way. Those skilled in the art will recognize other possible embodiments of closed-loop or semi-closed-loop diabetes control devices, and any such other embodiments are contemplated by the present disclosure.

In a first example embodiment of system 10, electronic device 12 is provided in the form of a conventional insulin pump that is configured to be worn outside of the body of a user and is also configured to controllably deliver insulin to the body of the user. In this example, a plurality of medical devices 26₁-26_NOne or more implantable sensors and/or sensor technology for providing information related to a physiological condition of a user may be included. Examples of such implantable sensors may include, but are not limited to, glucose sensors, body temperature sensors, blood pressure sensors, heart rate sensors, and the like. In embodiments that include an implantable glucose sensor, the system 10 may be a fully closed-loop system that may be operated in a conventional manner to automatically monitor blood glucose and (as the case may be) deliver insulin to maintain blood glucose at a desired level. A plurality of medical devices 26₁-26_NOne or more sensors or sensing systems located outside the user's body and/or sensor technology for providing information related to the physiological condition of the user may alternatively or additionally be included. Examples of such sensors or sensing systems may include, but are not limited to, glucose strip sensors/meters, body temperature sensors, blood pressure sensors, heart rate sensors, and the like. In embodiments that include an external glucose sensor, the system 10 may be a semi-closed loop system that may operate in a conventional manner to deliver insulin based on glucose information provided to it by the user (as the case may be). Information provided by any such sensors and/or sensor technologies may be communicated to system 10 using any one or more conventional wired or wireless communication technologies.

In a second example embodiment of the system 10, the electronic device 12 is provided in the form of a handheld remote device, such as a PDA or other handheld device. In this example, a plurality of medical devices 26₁-26_NIncluding at least one conventional implantable or externally worn drug pump. In one embodiment of this example, the insulin pump is configured to controllably deliver insulin to the body of the user. In this embodiment, the insulin pump is configured to wirelessly transmit information related to insulin deliveryTo the handheld device 12. The handheld device 12 is configured to monitor insulin delivery by the pump and may also be configured to determine and recommend insulin bolus amounts, carbohydrate intake, exercise, etc. In this embodiment, the system 10 may or may not be configured to provide wireless communication of information from the handheld device 12 to the insulin pump.

In an alternative embodiment of this example, the handheld device 12 is configured to control insulin delivery to the user by determining insulin delivery commands and communicating such commands to the insulin pump. And the insulin pump is configured to receive insulin delivery commands from the handheld device 12 and deliver insulin to the user upon command. In this embodiment, the insulin pump may or may not further process the insulin pump commands provided by the handheld device 12. In any event, in this embodiment, the system 10 will generally be configured to provide for wireless communication of information from the insulin pump back to the handheld device 12 to thereby allow monitoring of pump operation. In any of the embodiments of this example, system 10 may further include one or more implantable and/or external sensors of the types described in the preceding examples.

Those skilled in the art will recognize other possible implementations of closed-loop or semi-closed-loop diabetes control devices that use at least some of the components of the system 10 shown in FIG. 1. For example, the electronic device 12 in one or more of the above examples may be provided in the form of a laptop, notebook, or personal computer configured to communicate with one or more medical devices 26₁-26_N(the medical device 26₁-26_NAt least one of which is an insulin pump) for monitoring and/or controlling the delivery of insulin to the user. As another example, system 10 may also include a remote device (not shown) configured to communicate with electronic device 12 and/or one or more medical devices 26₁-26_NCommunication is performed to control and/or monitor the delivery of insulin to the patient. The remote device may be located in the caregiver's office or at another remote location, and between the remote device and any of the components of system 10Communication may be accomplished via an intranet, the internet (e.g., world wide web), cellular, telephone modem, RF, or other communication lines. Any one or more conventional internet protocols may be used in such communication. Alternatively or additionally, any conventional mobile content delivery system (e.g., Short Message System (SMS)) or other conventional messaging scheme (message schema) may be used to provide communication between the devices comprising system 10. In any event, any such other embodiments are contemplated by the present disclosure.

Generally, glucose concentrations vary in people with diabetes due to one or more external influences such as diet and/or exercise, and may also vary due to various physiological mechanisms such as stress, menstrual cycle, and/or disease. In any of the above examples, by determining the appropriate amount of insulin to be administered, the system 10 responds to the measured glucose in order to maintain normal blood glucose levels without causing hypoglycemia. In some embodiments, system 10 is implemented as a discrete system with an appropriate sampling rate, which may be periodic, aperiodic, or triggered, although other continuous (analog) or hybrid systems may alternatively be implemented as described above.

As one example of a traditional diabetes control system, the one or more software algorithms may include a set of rule sets that use (1) glucose information, (2) insulin delivery information, and/or (3) subject inputs (inputs) such as meal intake, exercise, stress, disease, and/or other physiological attributes to provide therapy, etc. to manage the user's glucose levels. The rule set is typically based on observations and clinical practices, as well as on an analysis of physiological mechanisms obtained from clinical studies or a mathematical model derived based on the analysis. In the example system, models of insulin pharmacokinetics and pharmacodynamics, glucose pharmacodynamics, meal absorption and motor response of individual patients are used to determine the timing and amount of insulin to be delivered. A learning module may be provided to allow adjustment of model parameters when a patient's overall performance metric (performance metric) decreases (e.g., an adaptive algorithm may be implemented using Bayesian (Bayesian) estimation). An analytical model can also be incorporated that examines learning to accept or reject learning. The adjustment is achieved using heuristics, rules, formulas, minimizing cost function(s) or tables (e.g., gain scheduling).

However, human metabolism is complex and difficult to fully understand. The solution space for managing glucose in daily life is currently limited. Daily variability, incorrect or inaccurate input, equipment malfunction, physiological changes, exercise, stress, illness, etc. are known to produce changes in the condition of a diabetic patient. The working premise with conventional diabetes control systems is that the various device components are working properly and that the method or logic or process of determining treatment is consistent with the operational premise. These preconditions are often inaccurate for an actual diabetes control system, and physical implementations of conventional diabetes control systems will often encounter failure modes that the system is unable to correct. Such failure modes may be detected by the diabetes control system, while other failure modes may only be detected by the user.

The following is a list of example failure modes that may be detected by the diabetes control system. This list is not intended to be exhaustive or limiting, but is provided merely as an example.

1.Measuring drift error

In diabetes control systems, measurement drift is usually corrected from time to time with recalibration. Measured glucose (G)_M) And true glucose (G) can be determined according to equation G_MModeling G + e, where e is the measurement error. If left unchecked, error e may result in G_MUnacceptable errors in the error. There may be one or more reasons why the system is unable to correct the glucose measurement.

2.Algorithm model and parameters thereof

Models within the system typically use approximations of the subject and device components to determine the treatment. The structure and parameters of the model define the expected characteristics. However, the assumptions of the model may be wrong; the internal state of the model may not match the actual object, thereby causing performance errors.

One example model (and potential source of performance error associated therewith) is a meal model. Errors in predicting meal absorption characteristics may result from errors in the dynamic performance described by the shape of the user's carbohydrate absorption profile. Errors in timing and errors in the shape of the profile may cause the diabetes control system to orient the user's glucose level toward a hyperglycemic or hypoglycemic condition. Similar considerations and sources of error exist with respect to glucose measurement subcutaneous models, insulin absorption subcutaneous models (for various insulin types), motor models, pressure models, and glucose-insulin kinetics, among others.

3.Feedback system

Any of a variety of conventional controller design methods (such as PID systems, full state feedback systems with state estimators, output feedback systems, LQG controllers, LQR controllers, eigenvalue/eigenstructure controller systems, etc.) may be used to design algorithms to perform physiological control. These controller design methods typically operate by using information derived from physiological measurements and/or user input to determine the appropriate control actions to use. While the simpler versions of such controllers use fixed parameters (and hence rules) to calculate the magnitude of the control action, the parameters in more complex versions of such controllers may use one or more dynamic parameters. The one or more dynamic parameters may for example take the form of one or more continuously or discretely adjustable gain values. The specific rules for adjusting such gains may be defined, for example, on an individual basis or on a patient group (patient population) basis, and in either case will typically be derived from one or more mathematical models. Such gains are typically planned (scheduled) according to one or more rule sets designed to cover the desired operating range in which operation is typically non-linear and variable, thereby reducing the source of error. However, errors in such feedback systems exist and can therefore accumulate and cause unacceptable system errors.

4.Model-based control system

For example, a model describing a patient may be constructed as a "black box" in which equations and parameters do not have a strict simulation of physiology. Rather, such a model may instead be a representation suitable for physiological control. The parameters are typically determined by measurements of physiological parameters such as blood glucose, insulin concentration, etc., as well as by physiological inputs such as food intake, alcohol intake, insulin dosage, etc., and also by physiological states such as stress level, exercise intensity and duration, menstrual cycle phase, etc. These models are used to estimate current glucose or predict future glucose values. Insulin therapy is derived by a system that predicts the ability of glucose for various inputs based on a model. Other conventional modeling techniques may additionally or alternatively be used including, for example, but not limited to, modeling by first principles. Errors in any such model type may result from various causes, such as erroneous estimates of model parameters, non-linear and/or time-varying parameters, unmodeled system dynamics, erroneous dynamics, and so forth.

5.Various factors affecting controller performance

Errors arise from delays in action response, delays in measuring glucose, processing delays, delays caused by system operation cycle steps, and the like.

It is also desirable to provide the ability to recover from situations where the system 10 is not or cannot detect due to a failure. For example, due to one or more of the above-described sources of systematic error, the system 10 may direct the user's insulin sufficiently towards hyperglycemia or hypoglycemia such that the resulting symptoms are recognized or recognized by the user even if the system 10 does not indicate any errors or failure modes. System errors/malfunctions and/or user symptoms may be accelerated or decelerated due to the user's physiological state, including, for example, illness, stress, etc.

The system 10 provides for user intervention in one or more of the types of diabetes control devices described above. In particular, the input device 18 includes one or more user intervention input mechanisms that allow a user to intervene in the controlled insulin delivery algorithm being executed by the diabetes control device in a manner that allows the insulin delivery algorithm to continue to execute without resetting or otherwise disabling the algorithm and/or system. By appropriately selecting/activating one or more user intervention input mechanisms, the user takes a corrective action and then either allows the insulin delivery algorithm to act upon the corrective action (optionally with or without a delay) by including the corrective action in the execution of the insulin delivery algorithm, or overrides (and does not act upon) the corrective action by excluding the corrective action from the execution of the insulin delivery algorithm. In either case, however, the user will enter corrective action into the system 10. In one embodiment, the input device 18 includes two user selectable buttons. By pressing one of the two user selectable buttons, the user can intervene in the diabetes control arrangement, take corrective action, and then allow the insulin delivery algorithm being executed to act upon the corrective action. By pressing the other of the two user selectable buttons, the user can intervene in the diabetes control arrangement and take corrective action, wherein the corrective action is excluded from the insulin delivery algorithm being executed. In either case, the corrective action is entered into a database in a storage unit or other data storage device 16. Also, in either case, the insulin delivery algorithm is continuously executing, and user intervention information may also be processed according to an appropriate selection of user intervention input mechanisms.

In an alternative embodiment, the display 20 includes a Graphical User Interface (GUI) that allows a user to freely select either of two user-selectable display icons. In this embodiment, selecting either of the two displayed icons will have the same effect as selecting either of the two user-selectable buttons in the previous example. It will be appreciated that more, fewer and/or other user-selectable input mechanisms may be provided to allow a user to intervene in the diabetes control arrangement at will, and to select between allowing the system 10 to act upon the corrective action taken in the intervention and causing the system 10 to override the corrective action taken in the intervention. Any such alternative user-selectable mechanism is contemplated by the present disclosure.

As just described, the user may intervene in the diabetes control arrangement for taking either of two possible corrective actions; that is, action is taken to lower the user's glucose level or action is taken to increase the user's glucose level. Traditional mechanisms for lowering a user's glucose level include, but are not limited to, dispensing insulin into the user's body, such as in the form of pills and exercise. Traditional mechanisms of increasing a user's glucose level include, but are not limited to, systems that ingest carbohydrates and dispense glycogen to the user. Any corrective action taken by the user is independent of system logic and device considerations within system 10. This user intervention allows the system 10 to continue operating under the insulin delivery algorithm while also allowing the system 10 to recover without requiring a system reset.

Referring now to FIG. 2, a flow diagram of one exemplary embodiment of a software algorithm 100 for providing user intervention in a diabetes control arrangement is shown. The algorithm 100 is typically stored in a memory unit or other data storage device 16 and will be executed by the processor 14. In the illustrated embodiment, it will be understood that the processor 14 will simultaneously or cooperatively execute one or more conventional insulin delivery algorithms configured to manage or control the delivery of insulin to the user, and the algorithm 100 will therefore be executed by the processor 14 as a stand-alone algorithm. Alternatively, the algorithm 100 and one or more conventional insulin delivery algorithms may be executed by different processors in embodiments of the system 10 that include multiple processors. In any case, for purposes of this document, the algorithm 100 will be described as being executed by the processor 14. In this description, it will be understood that the algorithm 100 treats user intervention as an asynchronous case requiring immediate attention, as opposed to synchronous (e.g., periodic) events that the system 10 typically manages according to one or more insulin delivery algorithms. The algorithm 100 begins at step 102 and thereafter at step 104 the processor 14 is operable to monitor one or more of the user intervention input mechanisms described above. Thereafter at step 106, the processor 14 is operable to determine whether one of the one or more user intervention input mechanisms has been selected or activated. If the user intervention input mechanism is not selected or activated, algorithm execution loops back to step 104. If the user intervention input mechanism has been selected or activated, this means that the user has manually selected one of the two user intervention input mechanisms, and algorithm execution proceeds to step 108, at step 108 processor 14 is operable to input the user intervention event, date and time into a database contained within the memory unit or other data storage device 16. Thereafter at step 110, the processor 14 is operable to determine an Intervention Insulin Quantity (IIQ) or an Intervention Carbohydrate Quantity (ICQ).

As mentioned above, as just described, the user may intervene in the diabetes control arrangement for taking either of two possible corrective actions: or by taking action to lower the user's glucose level, for example by receiving insulin, such as in the form of a bolus, and/or via one or more other conventional glucose lowering mechanisms; or by taking action to increase the user's glucose level, for example, by ingesting carbohydrates and/or via one or more other conventional glucose increase mechanisms. In the event that the user chooses to intervene by ingesting additional insulin, the user may intervene via any conventional technique. Examples include, but are not limited to, manually overriding (override) the system 10 in a conventional manner in order to direct the system 10 to deliver a specific amount of insulin, programming the system 10 to deliver a specific amount of insulin in a conventional manner, manually injecting a specific amount of insulin via a syringe, etc. In any case, the user inputs a specified amount of insulin into the system 10 via an appropriate one of the input devices 18, and the processor 14 performs step 110 by receiving the specified amount of insulin (or an intervening insulin amount (IIQ)) from the input device 18. In the case where the user chooses to intervene by ingesting carbohydrates, the user enters the amount of carbohydrates that are ingested into the system 10 via the appropriate input device 18. In this case, the processor 14 performs step 110 by receiving the Intervention Carbohydrate Quantity (ICQ) from the input device 18. In either case, it will be appreciated that the algorithm 100 will typically also include one or more steps that provide a timeout mechanism that allows the algorithm 100 to continue execution after a predetermined period of time when the user fails to enter (or incompletely enters) IIQ or ICQ information at step 110. Any such step or steps would be a mechanical movement for an experienced algorithm designer.

From step 110, the algorithm 100 proceeds to step 112, wherein the processor 14 is operable to determine whether the system 10 should act upon user intervention in the form of the corrective action taken at step 110 or whether such user intervention should not be considered. In the illustrated embodiment, processor 14 is operable to execute step 112 in accordance with the particular user intervention input detected at step 106. More specifically, if the operation of the system 10 is user intervention by selecting a user intervention input designated for action, the algorithm 100 proceeds to step 114, wherein the system 10 is operable to act upon or otherwise process the corrective action taken by the user. At step 114, the processor 14 is operable to determine whether the corrective action detected at step 106 corresponds to the administration of insulin or the ingestion of carbohydrates. In the illustrated embodiment, processor 14 is operable to perform step 114 by determining the nature of the parameter received at step 110. More specifically, if the parameter IIQ is received at step 110, algorithm execution advances from step 114 to step 116, and at step 116, the processor 14 executes an IIQ processing routine that allows the one or more insulin delivery algorithms executed by the processor 14 to include the intervention insulin quantity IIQ in executing the insulin delivery algorithm under the direction of the IIQ processing routine. On the other hand, if the parameter ICQ is received at step 110, algorithm execution advances from step 114 to step 118, and at step 118, processor 14 is operable to time and date stamp the ICQ and then enter this data into a database portion of a memory unit or other data storage device 16. Following step 118, the processor 14 is operable at step 120 to execute an ICQ processing routine that allows one or more insulin delivery algorithms executed by the processor 14 to include the intervention carbohydrate quantity, ICQ, in executing the insulin delivery algorithm under the direction of the ICQ processing routine. If, at step 112, user intervention occurs with the user intervention input being selected for non-action, the algorithm proceeds from step 112 to step 122, at step 122, the processor 14 is operable to time and date stamp the corrective actions IIQ and ICQ, and then enter this data into a database portion of the memory unit or other data storage device 16. In this case, the processor 14 excludes the corrective action IIQ or ICQ from the one or more insulin delivery algorithms executed by the processor 14 such that the system 10 does not act in compliance with the corrective action taken by the user. The algorithm 100 loops back to step 104 from any of steps 116, 120, and 122.

Referring now to FIG. 3, a flowchart of one exemplary embodiment of the IIQ processing routine of step 116 of the algorithm 100 of FIG. 2 is shown. In the illustrated embodiment, routine 116 may include an optional step 150, which optional step 150 allows for an optional delay period before proceeding with the IIQ action. For example, step 150 may include step 152, where processor 14 is operable to determine whether to delay before acting on the IIQ at step 152. In one embodiment, processor 14 is operable to perform step 152 by prompting the user to enter the delay time DT. If the user enters zero via the appropriate input device 18, execution of the routine proceeds to step 158. On the other hand, if the user input is positive, then execution of routine 116 proceeds to step 154, and at step 154, processor 14 is operable to receive the user input delay time DT. In an alternative embodiment, processor 14 is operable to execute step 152 by prompting the user to answer yes or no for whether to delay before processing the IIQ. If the user enters "NO" via the appropriate input device 18, execution of the routine 116 proceeds to step 158. On the other hand, if the user answers "yes" at step 152, the processor 14 prompts the user to enter a delay time value DT via a suitable input device 18 at step 154. In any case, execution of the routine 116 proceeds from step 154 to step 156, where the processor 14 is operable to wait for a time period equal to DT at step 156 before proceeding to step 158. Optional step 150 may also include one or more steps designed to allow the user to cancel the intervention and/or accept/confirm one or more additional user interventions during the delay period DT. Any such step or steps would be a mechanical movement for an experienced algorithm designer. It will be appreciated that in embodiments where the user specifies the delay time DT, the routine 116 will typically also include one or more steps that provide a timeout mechanism that allows the routine 116 to continue execution after a predetermined period of time when the user fails to enter (or incompletely enters) the delay time DT at step 154. Any such step or steps would be a mechanical movement for an experienced algorithm designer.

At step 158, in the illustrated embodiment of the IIQ processing routine 116, the processor 14 is operable to process the intervention insulin quantity IIQ by adding IIQ to the currently scheduled bolus quantity, wherein for step 158, "current" is defined as the point in the execution of the insulin delivery algorithm at which step 158 of the routine 116 is also executed. If a positive number (positive amount) of insulin boluses is currently scheduled for delivery to the user, the processor 14 is operable at step 158 to add the IIQ to the positive insulin bolus that has been scheduled for delivery to the user. On the other hand, if the bolus amount is not currently planned, i.e., the current bolus amount is zero, the processor 14 is operable to plan a bolus amount of IIQ according to the insulin delivery algorithm being executed by the processor 14. Thereafter, the system 10 is operable to manage delivery of the insulin bolus to the user in accordance with one or more insulin delivery algorithms being executed by the processor 14. In alternative embodiments of the IIQ processing routine 116, the processor 14 may be configured to control the insulin bolus to be delivered with the IIQ amount before, during, or after any currently scheduled insulin bolus is delivered. In any case, after performing step 158, the processor 14 is operable at step 160 to date and time stamp the IIQ and then enter the date and time stamped IIQ value into a memory unit or database portion of the other data storage device 16. Thereafter, at step 162, the routine 116 returns to the algorithm 100 of FIG. 2. It will be appreciated that in one or more embodiments of the system 10, it may be desirable to synchronize the date and/or time stamp of the IIQ with the reference date and/or time using one or more conventional date and/or time synchronization techniques. It will also be appreciated that the IIQ data is date and time stamped and then stored in the memory unit or other data storage device 16 at or near the time the intervention insulin quantity IIQ is scheduled to be delivered (or actually delivered) to the user. In the embodiment of routine 116 shown in fig. 3, this step occurs after optional delay step 150. In other embodiments, it will become apparent when the IIQ is date and time stamped and that information is entered into a memory unit or other data storage device 16 at the appropriate time. As a specific example, in embodiments in which the intervention insulin quantity IIQ is manually administered, it is appropriate to date and time stamp the IIQ data at or near the time the intervention insulin quantity was actually administered; such as immediately after step 110 of algorithm 100, for example. Similar considerations apply to the date, time stamping and storage of the intervention carbohydrate amount ICQ.

The routine 116 of FIG. 3 will typically be invoked and executed when a user intervenes in the operation of the diabetes control device via the algorithm 100 of FIG. 2 due to a high glucose event or condition. In one embodiment, a high glucose event or condition is defined by a high glucose threshold, a minimum duration above the threshold, and a rate of change of glucose defined by a maximum threshold rate (threshold rate) and a minimum threshold rate. The threshold may be based on predicted values or measured values or a combination thereof. In any case, the user may typically perform a high glucose intervention due to any one or more of the following:

1. the system 10 has marked the user's glucose as exceeding the high glucose threshold preset by the default setting,

2. the system 10 has marked the user's glucose as exceeding the high glucose threshold set by the health care professional,

3. the system 10 has marked the user's glucose as exceeding a high glucose threshold set by the user, the user's parent or guardian or other caregiver,

4. the user (or a third party) has identified high glucose events based on independent physical measurements of the user's glucose level,

5. the user (or third party) has identified high glucose events based on independent physiological symptoms/indicators, or

6. The system 10 has identified high glucose events based on analysis according to one or more predictive models.

As described above, the user may react to a high glucose event by administering an intervening insulin amount, such as in the form of a bolus. If the user chooses not to allow the processor 14 to act upon the amount of insulin to be administered IIQ, the insulin delivery algorithm executed by the diabetes control system 10 will not reduce the amount of insulin from future control actions. However, if the user chooses to allow the processor 14 to act upon the administered insulin quantity IIQ, the processor 14 plans to deliver an insulin bolus of the IIQ quantity.

Referring now to FIG. 4, a flowchart of one exemplary embodiment of the ICQ processing routine of step 120 of the algorithm 100 of FIG. 2 is shown. In the illustrated embodiment, the routine 120 may include an optional step 170, which optional step 170 takes into account an optional delay period before acting upon the ICQ. For example, step 170 may include step 172, where processor 14 is operable to determine whether to delay before acting on the ICQ at step 172. In one embodiment, processor 14 is operable to execute step 172 by prompting the user to enter the delay time DT. If the user enters zero via the appropriate input device 18, execution of the routine proceeds to step 178. On the other hand, if the user input is positive, then execution of routine 120 proceeds to step 174, and at step 174 processor 14 is operable to receive the user input delay time DT. In an alternative embodiment, processor 14 is operable to execute step 172 by alerting the user to delay the answer "yes" or "no" for whether to process the ICQ. If the user enters "NO" via the appropriate input device 18, execution of the routine 120 proceeds to step 178. On the other hand, if the user answers "yes" at step 172, the processor 14 prompts the user at step 174 to enter the delay time value DT via the appropriate input device 18. In any case, execution of the routine 120 proceeds from step 174 to step 176, where the processor 14 is operable to wait a time period equal to DT before proceeding to step 178 at step 176. Optional step 170 may also include one or more steps designed to allow the user to cancel the intervention and/or accept/confirm one or more additional user interventions during the delay period DT. Any such step or steps would be a mechanical movement for an experienced algorithm designer. It will be appreciated that in embodiments where the user specifies the delay time DT, the routine 120 will typically also include one or more steps of providing a timeout mechanism that allows the routine 120 to continue execution after a predetermined period of time when the user fails to enter (or incompletely enters) the delay time DT at step 174. Any such step or steps would be a mechanical movement for an experienced algorithm designer.

At step 178-The processor 14 is operable to process the intervention carbohydrate quantity ICQ, one or more insulin delivery algorithms executed by the processor 14. In the illustrated embodiment, the processor 14 is operable to process the intervention carbohydrate quantity, ICQ, by first determining a desired glucose boost function, EGP, at step 178, which is a normalized representation of a desired profile of glucose boost and, in this example, is scaled by ICQ and K_RIn which K is_RCorresponding to an increase in glucose per gram of carbohydrate. The expected glucose push function EGP is a normalized time-based glucose push function resulting from the ingestion of rapidly absorbed carbohydrate ICQ. Following step 178, the processor 14 is operable at step 180 to determine the EGP, ICQ, and K_RThe change Δ GSP of the current glucose target value (or glucose set point) is determined. More specifically, the change in glucose set point Δ GSP is determined as the linear reduction gain term [1- (Δ T/T)_D)]、ICQ、K_RProduct with the cumulative sum of EGP over time, where Δ T is the time elapsed from the instant of intervention, and T_DIs the duration for which the intervention action will last. In particular, [1- (Δ T/T) ]Δ GSP_D)]*ICQ*K_REGP (Δ t). After step 180, the processor 14 is operable at step 182 to determine the glucose target value or set point GSP as the sum of the current glucose set point and the change in the glucose set point, or GSP + Δ GSP. Thereafter, the routine 120 returns to the algorithm 100 of FIG. 2 at step 186. It will be appreciated that in one or more embodiments of the system 10, it may be desirable to synchronize the date and/or time stamp of the ICQ with a reference date and/or time using one or more conventional date and/or time synchronization techniques.

In the embodiments shown herein, it is generally contemplated that the intervention insulin carbohydrate amount, ICQ, is provided in the form of rapidly absorbed carbohydrates, as that term is generally understood in the art. In this embodiment, the ICQ will typically be provided in the form of one or more rapidly absorbed carbohydrate foods and/or liquids, or alternatively in the form of pills or chewable tablets, or alternatively also in the form of an injectable medicament (such as glycogen). In alternative embodiments of the system 10, the algorithm 100 and/or routine 120 may be modified to allow user intervention by ingesting or otherwise receiving rapidly absorbed carbohydrates or by ingesting or otherwise receiving slower absorbed carbohydrates. In such embodiments, the system 10, algorithm 100, and routine 120 may be modified to distinguish carbohydrates ingested or otherwise received in the form of rapidly absorbed carbohydrates from carbohydrates ingested or otherwise received in the form of slower absorbed carbohydrates. In such embodiments, the system 10 would provide user input of such information, the algorithm 100 may allow the user to input the type of carbohydrates being ingested or otherwise received, and the routine 120 may respond to the type of carbohydrates being ingested by the user by, for example, selecting, calculating, or otherwise determining an appropriate Δ GSP based on the carbohydrate type. Any such modifications to the system 10, algorithm 100, and/or routine 120 would be a mechanical step to a skilled artisan.

The routine 120 of FIG. 4 will typically be called or executed when a user intervenes in the operation of the system 10 via the algorithm 100 of FIG. 2 due to a low glucose event or condition. In one embodiment, a low glucose event or condition is defined by a lower glucose threshold and a rate of glucose change defined by a maximum threshold rate and a minimum threshold rate. The threshold value may be based on predicted values or measured values or a combination thereof. In any case, the user may perform a low glucose intervention, typically due to one or more of the following:

1. the system 10 has marked the user's glucose as exceeding the low glucose threshold preset by the default setting,

2. the system 10 has marked the user's glucose as exceeding the low glucose threshold set by the health care professional,

3. the system 10 has marked the user's glucose as exceeding a low glucose threshold set by the user, the user's parent or guardian or other caregiver,

4. the user (or a third party) has identified low glucose events based on independent physical measurements of the user's glucose level,

5. the user (or third party) has identified low glucose events based on independent physiological symptoms/indicators, or

6. The system 10 has identified low glucose events based on analysis according to one or more predictive models.

The user may react to the low glucose event by ingesting or otherwise receiving a carbohydrate composition, such as in the form of a rapidly absorbed carbohydrate food and/or liquid, one or more glucose-increasing pills or chewable tablets, and/or a glucose-increasing medication. This action is intended to increase the glucose level of the user back to the normal blood glucose range (glycemic range). If the user chooses not to allow the processor 14 to act upon the intervention carbohydrate quantity ICQ by excluding the ICQ from the insulin delivery algorithm being executed by the processor 14, the system 10 will not attempt to counteract the resulting increase in glucose by recommending additional insulin. However, if the user chooses to allow the processor 14 to act upon the ICQ by including the intervention carbohydrate amount ICQ in the execution of the insulin delivery algorithm being executed by the processor 14, the system 10 may attempt to counteract this glucose boost by recommending delivery of additional insulin. Thus, step 178-182 of the routine 120 of FIG. 4 adds a time-decay function to the existing glucose target or set point GSP. Initially by modifying the glucose set point GSP by an amount equal to the expected rising EGP, the system 10 will not attempt to counteract the glucose rise due to ingestion of rapidly absorbed carbohydrates. The time decay function Δ GSP allows the modified glucose set point GSP to return to its original set point after a certain time has elapsed. It will be appreciated that other conventional techniques may be used to allow the one or more insulin delivery control algorithms being executed by the processor 14 to gradually return to normal operation after ingestion or otherwise receiving user intervention in the form of a glucose increasing compound. As an example of one such alternative technique, the system 10 may be configured to temporarily modify the allowable insulin rate of rise and allow the allowable insulin rate of rise to return to normal after a certain amount of time has elapsed. This and any other such alternative techniques are contemplated by the present disclosure for allowing the one or more insulin delivery control algorithms being executed by processor 14 to return to normal operation after ingestion or otherwise receipt of user intervention in the form of a glucose-increasing compound.

An example of a situation in which the user may suitably instruct the system 10 not to take account of user intervention occurs with a glucose rise related to a meal resulting from ingestion of a meal of unknown or partially known composition. If the dynamic response of the system 10 does not properly match the meal composition, the system 10 may inadvertently push the diabetic subject into a hypoglycemic condition. As described herein, user intervention allows for processing of unknown dynamics in a controlled manner; for example, to handle unknown meal loads.

A meal is typically covered with the system 10 by controllably dispensing insulin doses based on the predicted meal absorption profile under the control of an insulin delivery algorithm being executed by the processor 14. The insulin profile is determined so as to optimally minimize the glucose rise and to bring the glucose to the target glucose level as quickly as possible with a minimum negative pulse signal. However, clinical data have shown large variability in absorption due to complications associated with meal composition, the presence of prior meal effects and influences, inaccuracies in meal size measurement techniques, meal consumption patterns, and the like. Such large variability (if observed) may be best handled with the user intervention system described herein, for example, by withstanding momentary uncertainties. Other conventional techniques for responding to such variability use one or more conventional techniques.

The glucose rise due to dietary intake cannot be completely removed. This is expected since the delay in peak insulin action is typically about 30-60 minutes. The insulin dose obtained is optimized to minimize the glucose rise due to meals. In the case of a meal event, the target glucose zone relating to the meal is defined as the area bounded by the upper and lower target glucose boundaries. With respect to the defined target zone, the following four situations occur:

1.within the glucose region

If the predicted glucose value is within the glucose zone boundary, the user's glucose is considered to be within acceptable limits. Under the insulin delivery algorithm being executed by the processor 14, the processor 14 assumes that the blood glucose characteristics are within acceptable limits and continues to recommend insulin without correcting for glucose excursions.

2.Above the glucose region

If the predicted glucose is above the upper glucose boundary, the user is deemed to be in a situation where too little insulin is delivered (under-delivered in insulin). Under control of the insulin delivery algorithm being executed by the processor 14, the processor 14 calculates the deviation of glucose from the upper glucose boundary. Basic controller action (basal control) is the cause of this deviation and will be suppressed for this unexplained rise.

3.Under the glucose region

If the predicted glucose is below the lower glucose boundary, the user is deemed to be in the event of excessive insulin delivery (over-delayed in insulin). Under control of the insulin delivery algorithm being executed by the processor 14, the processor 14 calculates the deviation of glucose from the lower glucose boundary. The basic controller action is the cause of this deviation and will be suppressed for this unexplained drop.

4.No glucose turnover

The target zone covers the expected rise and fall of responses related to meals. A special case occurs when the glucose information in the system 10 is not updated; special cases arise, for example, when no new measurement has been received due to a previous measurement or within a pre-planned interval. Without updating the glucose measurement, the predicted glucose for the current control cycle is a glucose value that does not account for glucose rises or falls related to meals. However, the target zone boundary is a function of time. This generally means that the predicted glucose is lower when the effect of the meal on the human begins to occur, and higher when the effect of the meal on the human gradually ceases. This effect is exacerbated as the dietary zone boundary is raised or lowered. The insulin delivery algorithm being executed by the processor 14 handles this situation by maintaining an upper bound limit for use with the last received glucose measurement. These upper and lower target values remain fixed for all future control cycles until a new measurement is available.

While the invention has been illustrated and described in the foregoing drawings and description, the same is to be considered as illustrative and not restrictive in character, it being understood that only illustrative embodiments thereof have been shown and described and that all changes and modifications that come within the spirit of the invention are desired to be protected. For example, the concepts described herein may be applied to other medical control devices having a processor that executes a drug delivery algorithm that forms part of the medical control device. In any such system, the processor may be responsive to the first user intervention signal to include an intervention therapy value in the execution of the drug delivery algorithm and to the second user intervention signal to exclude the intervention therapy value from the execution of the drug delivery algorithm. The intervention therapy value may correspond to various medical treatments administered to and/or performed by the user, including, for example, but not limited to, delivering one or more drugs, such as delivering insulin, glycogen, or other drugs, administering one or more other drugs, and/or achieving one or more effects that have an opposite effect as delivering one or more drugs, ingesting carbohydrates, performing one or more physical exercises, and the like. Other examples will occur to those of ordinary skill in the art and any such other examples are contemplated by the present disclosure.

As another example, the electronic device 12 of FIG. 1 may include several selectable input mechanisms for acting upon and not acting upon user intervention. As a particular example, the device 12 may include a plurality of "preset" input mechanisms that allow the user to select a preset amount of insulin from a plurality of selectable preset insulin amounts for delivery to the user.

As yet another example, system 10 may receive multiple user intervention requests, such as a delay action according to optional steps 150 or 170 of routines 116 and 120, respectively. In this case, a plurality of requests may be executed as a group. Alternatively, system 10 may include one or more prioritization algorithms configured to prioritize various user intervention events based on one or more predetermined, programmable, or user-selectable criteria.

Claims

1. A system for providing user intervention in a diabetes control arrangement, the system comprising:

means responsive to user selection thereof for generating one of the first and second user intervention signals, an

A processor executing an insulin delivery algorithm forming part of the diabetes control arrangement, the processor including one of an intervention insulin quantity and an intervention carbohydrate quantity in the executing insulin delivery algorithm in response to the first user intervention signal, and excluding the one of the intervention insulin quantity and the intervention carbohydrate quantity from the executing insulin delivery algorithm in response to the second user intervention signal.

2. The system of claim 1, wherein the processor is configured to continuously and uninterrupted execute the insulin delivery algorithm regardless of whether the first or second user intervention signal is generated.

3. The system of claim 1 or 2 further comprising means for providing one of the intervention insulin quantity and the intervention carbohydrate quantity to the processor.

4. The system of claims 1-3 wherein the processor is responsive to the first user intervention signal to process the intervention insulin quantity by adding the intervention insulin quantity to the current insulin bolus quantity.

5. The system of claim 4 wherein the processor is further responsive to the first user intervention signal to command administration of the combination of the intervention insulin quantity and the current insulin bolus quantity to the user.

6. The system of claim 4 or 5, wherein the current insulin bolus amount is a positive-value insulin bolus amount.

7. The system of claims 4-6, wherein the current insulin bolus quantity is a zero-value insulin bolus quantity.

8. The system of claims 1-7 wherein the processor is responsive to the first user intervention signal to process the intervention carbohydrate quantity by modifying the blood glucose target as a function of the intervention carbohydrate quantity.

9. The system of claims 1-8, further comprising a database having stored therein insulin delivery and intervention carbohydrate information,

and wherein the processor inputs one of the intervention insulin quantity and the intervention carbohydrate quantity into the database in response to either of the first and second user intervention signals.

10. The system of claims 1-9 wherein the processor is operable to wait for a delay time before including one of the intervention insulin quantity and the intervention carbohydrate quantity in the execution of the insulin delivery algorithm.

11. A method of allowing a user to intervene in a diabetes control arrangement, the method comprising:

executing an insulin delivery algorithm, the insulin delivery algorithm forming part of the diabetes control device,

monitoring the first and second user intervention mechanisms,

in response to a user selection of the first user intervention mechanism, including one of the intervention insulin quantity and the intervention carbohydrate quantity in executing the insulin delivery algorithm, an

In response to the user selecting the second user intervention mechanism, excluding one of the intervention insulin quantity and the intervention carbohydrate quantity from executing the insulin delivery algorithm.

12. The method of claim 11 further comprising receiving one of an intervention insulin amount and an intervention carbohydrate amount.

13. The method of claim 11 or 12 further comprising inputting one of the intervention insulin quantity and the intervention carbohydrate quantity into the database in response to a user selecting either of the first and second user intervention mechanisms.

14. The method of claim 13 further comprising date and time stamping the one of the intervention insulin quantity and the intervention carbohydrate quantity prior to entering the one of the intervention insulin quantity and the intervention carbohydrate quantity into the database.

15. The method of claims 11-14, further comprising waiting a delay time after the user selects the first user intervention mechanism and before including one of the intervention insulin quantity and the intervention carbohydrate quantity in the execution of the insulin delivery algorithm.

16. A system for providing user intervention in a medical control device, the system comprising:

a first user intervention mechanism that generates a first user intervention signal in response to a user selection thereof,

a second user intervention mechanism that generates a second user intervention signal in response to a user selection thereof, an

A processor executing a drug delivery algorithm forming part of the medical control device, the processor including an intervention drug quantity in the executing of the drug delivery algorithm in response to the first user intervention signal, and excluding the intervention drug quantity from the executing of the drug delivery algorithm in response to the second user intervention signal.

17. The system of claim 16 further comprising means for receiving an intervention drug quantity.

18. The system of claim 16 or 17 wherein the medical control arrangement is a diabetes control arrangement, the drug delivery algorithm is an insulin delivery algorithm and the intervention drug quantity is an intervention insulin quantity.

19. The system of claim 18 wherein the processor is responsive to the first user intervention signal to include the intervention insulin quantity in the execution of the insulin delivery algorithm by adding the intervention insulin quantity to the current insulin bolus quantity.

20. The system of claim 19 wherein the processor is further responsive to the first user intervention signal to command administration of the combination of the intervention insulin quantity and the current insulin bolus quantity to the user.

21. The system of claims 16-20, further comprising a database having drug delivery information stored therein,

wherein the processor enters the intervention drug quantity into the database in response to either of the first and second user intervention signals.

22. The system of claim 21 wherein the processor is configured to date and time stamp the intervention drug quantity prior to entry into the database.

23. The system of claims 16-22 wherein the processor is operable to wait for a delay time before including the intervention drug quantity in the execution of the insulin delivery algorithm.

24. The system of claims 16-23 wherein the processor is configured to continuously and uninterrupted execute the drug delivery algorithm regardless of whether the first or second user intervention signal is generated.

25. A method of allowing user intervention in a medical control device, the method comprising:

executing a drug delivery algorithm, the drug delivery algorithm forming part of the medical control device,

monitoring the first and second user intervention mechanisms,

in response to a user selection of a first user intervention mechanism, including an intervention drug quantity in the execution of the drug delivery algorithm, an

The intervention drug quantity is excluded from execution of the drug delivery algorithm in response to user selection of the second user intervention mechanism.

26. The method of claim 25 further comprising receiving an intervention drug quantity.

27. The method of claim 25 or 26 further comprising entering the intervention drug quantity into the database in response to a user selecting either of the first and second user intervention mechanisms.

28. The method of claim 27 further comprising date and time stamping the intervention drug quantity prior to entering the intervention drug quantity into the database.

29. The method of claims 25-28 further comprising waiting a delay time after the user selects the first user intervention mechanism and before including the intervention drug quantity in the execution of the drug delivery algorithm.

30. The method of claims 25-29 wherein the medical control device is a diabetes control device, the drug delivery algorithm is an insulin delivery algorithm, and the intervention drug amount is an insulin intervention amount.

31. A system for providing user intervention in a medical control device, the system comprising:

A processor executing a drug delivery algorithm forming part of the medical control device, the processor being responsive to the first user intervention signal to include an intervention therapy value in the execution of the drug delivery algorithm and the processor being responsive to the second user intervention signal to exclude the intervention therapy value from the execution of the drug delivery algorithm.

32. The system of claim 31, further comprising means for receiving an intervention therapy value.

33. The system of claim 31 or 32 wherein the medical control device is a diabetes control device, the drug delivery algorithm is an insulin delivery algorithm and the intervention therapy value is an intervention insulin quantity.

34. The system of claims 31-33 wherein the medical control arrangement is a diabetes control arrangement, the drug delivery algorithm is an insulin delivery algorithm, and the intervention therapy value is an intervention carbohydrate amount corresponding to a quantity of carbohydrates recently intervened by the user.

35. The system of claim 34 wherein the processor is responsive to the first user intervention signal to include the intervention carbohydrate amount in executing the insulin delivery algorithm by modifying the blood glucose target as a function of the intervention carbohydrate amount.

36. The system of claims 31-35, further comprising a database having treatment value information stored therein,

wherein the processor enters the intervention therapy value into the database in response to either of the first and second user intervention signals.

37. The system of claim 36 wherein the processor is configured to date and time stamp the intervention therapy value prior to entering the intervention therapy value into the database.

38. The system of claims 31-37, wherein the processor is operable to wait for a delay time before including the intervention therapy value in the execution of the drug delivery algorithm.

39. The system of claims 31-38 wherein the processor is configured to continuously and uninterrupted execute the drug delivery algorithm regardless of whether the first or second user intervention signal is generated.

40. A method of allowing user intervention in a medical control device, the method comprising:

monitoring the first and second user intervention mechanisms,

including an intervention therapy value in executing the drug delivery algorithm in response to a user selecting a first user intervention mechanism, an

The intervention therapy value is excluded from executing the drug delivery algorithm in response to the user selecting the second user intervention mechanism.

41. The method of claim 40, further comprising receiving an intervention therapy value.

42. The method of claim 40 or 41, further comprising entering an intervention therapy value into the database in response to a user selecting either of the first and second user intervention mechanisms.

43. The method of claim 42 further comprising date and time stamping the intervention therapy value prior to entering the intervention therapy value into the database.

44. The method of claims 40-43, further comprising waiting a delay time after the user selects the first user intervention mechanism and before including the intervention therapy value in the execution of the drug delivery algorithm.

45. The method of claims 40-44, wherein the medical control device is a diabetes control device, the drug delivery algorithm is an insulin delivery algorithm, and the intervention therapy value is an insulin intervention quantity.

46. The method of claims 40-45 wherein the medical control device is a diabetes control device, the drug delivery algorithm is an insulin delivery algorithm, and the intervention therapy value is an intervention carbohydrate amount corresponding to a quantity of carbohydrates recently intervened by the user.