HK1107654A

HK1107654A - Insulin bolus recommendation system

Info

Publication number: HK1107654A
Application number: HK07113242.2A
Authority: HK
Inventors: Stefan Weinert; Robert Hellwig
Original assignee: Disetronic Licensing Ag
Priority date: 2004-08-26
Filing date: 2005-08-24
Publication date: 2008-04-11

Description

Insulin bolus recommendation system

The present invention relates generally to techniques for managing blood glucose levels in diabetic individuals, and more specifically to systems for determining and recommending insulin delivery as a way of managing blood glucose levels.

There are a variety of handheld systems for managing diabetes care. It is desirable to provide additional correction insulin bolus determinations and recommendations with such handheld systems to closely track and meet the insulin needs of the user. It would also be desirable to provide such additional correction insulin boluses before, during and after a meal bolus, while also allowing for natural but manageable blood glucose rise resulting from carbohydrate intake.

The invention may comprise one or more of the features recited in the appended claims or one or more of the following features and combinations thereof. A system for recommending insulin bolus quantities to an insulin user includes a data input device, a display unit, and a storage unit. The user blood glucose target may be established by storing the user blood glucose target in a memory unit. A method for recommending an insulin bolus amount may comprise the steps of: receiving a current blood glucose value of a user; determining a recommended insulin bolus amount if the current blood glucose value exceeds the blood glucose target; calculating the difference as the current blood glucose value minus the blood glucose target; and if the difference is positive, increasing the blood glucose target by the difference for a rest time period.

Alternatively or additionally, a method for recommending an insulin bolus quantity may comprise the steps of: receiving a current blood glucose value of a user at a first time; determining a first recommended insulin bolus amount if the current blood glucose value obtained at the first time exceeds the initial blood glucose target; calculating the first difference as the current blood sugar value and the initial blood sugar target of the user at the first moment; calculating the first modified glycemic target as a sum of the initial glycemic target and the first difference; receiving a current blood glucose value from the user at a second time after the first time and after the first recommended insulin bolus amount is dispensed to the user, but before expiration of a first stop time period since the first time; and determining a second recommended insulin bolus amount for the user if the current blood glucose value at the second time exceeds the first modified blood glucose target.

The method may further comprise the steps of: calculating a second difference as the user's current blood glucose value at a second time minus the first modified blood glucose target; and calculating the second modified glycemic target as a sum of the first modified glycemic target and the second difference. The method may still further comprise the steps of: receiving a current blood glucose value from the user at a third time after the second time and after the second recommended insulin bolus amount is dispensed to the user, but before expiration of the first stop time period since the first time and before expiration of the second stop time period since the second time; and determining a third recommended insulin bolus amount for the user if the current blood glucose value at the third time exceeds the second modified blood glucose target. The method also includes the steps of: calculating a third difference as the user's current blood glucose value at a third time minus a second modified blood glucose target; and calculating the third modified glycemic target as a sum of the second modified glycemic target and the third difference.

Alternatively, the method may further comprise the steps of: after the second time, receiving the current blood glucose value from the user at a third time after the second recommended insulin bolus amount is dispensed to the user and after expiration of the first stop time period since the first time, but before expiration of the second stop time period since the second time; calculating a third modified glycemic target as the second modified glycemic target minus the first difference; and determining a third recommended insulin bolus amount for the user if the current blood glucose value at the third time exceeds the third modified blood glucose target. The method may further comprise the steps of: the third difference is calculated as the user's current blood glucose value at the third time instant minus the third modified blood glucose target, and the fourth modified blood glucose target is calculated as the sum of the third modified blood glucose target and the third difference.

Alternatively or additionally, a method for recommending insulin bolus quantities to an insulin user comprises the steps of: establishing a glycemic target for the user; receiving a carbohydrate value representing an amount of carbohydrate to be subsequently ingested by a user; determining a recommended compensated insulin bolus amount based on the carbohydrate value; and increasing the glycemic target by a post-prandial increase value if the carbohydrate value exceeds the threshold value to produce a first modified glycemic target at the post-prandial rest time period. The method may further comprise the steps of: receiving a first current blood glucose value of the user after dispensing the recommended bolus of compensated insulin to the user, but before expiration of the post-prandial rest time period; determining a first recommended corrected insulin bolus amount if the first current blood glucose value exceeds the first modified blood glucose target; calculating a first difference as the first current blood glucose value minus the first modified blood glucose target; and if the first difference is positive, increasing the blood glucose target by the first difference to produce a second modified blood glucose target at the first corrected stop time period. The method may further comprise the steps of: after dispensing the recommended compensation insulin bolus to the user, after dispensing the first recommended correction insulin bolus to the user, and after expiration of the post-prandial rest time period, but before expiration of the first correction rest time period, receiving a second current blood glucose value of the user; decreasing the second modified glycemic target by the postprandial increase value to produce a third modified glycemic target; determining a second recommended corrected insulin bolus amount if the second current blood glucose value exceeds the third modified blood glucose target; calculating a second difference as the second current blood glucose value minus the third modified blood glucose target; and if the second difference is positive, increasing the blood glucose target by the second difference to produce a fourth modified blood glucose target at a second correction stop time period.

Alternatively or additionally, a method for recommending insulin bolus quantities to an insulin user may comprise the steps of: establishing a glycemic target for the user; receiving a first current blood glucose value of the user and a carbohydrate value representing an amount of carbohydrate to be subsequently ingested by the user; determining a recommended compensated insulin bolus amount based on the carbohydrate value; determining a first recommended corrected insulin bolus amount if the first current blood glucose value exceeds the blood glucose target; increasing the blood glucose target by a postprandial increase value for a postprandial rest time period if the carbohydrate value exceeds the threshold value; and if the first difference is positive, increasing the blood glucose target by the first difference for a first correction stop time period, the first difference calculated as the first current blood glucose value minus the blood glucose target. The blood glucose target increased by the post-meal increase value, the first difference value, or both the post-meal increase value and the first difference value corresponds to the first modified blood glucose target.

The method may further comprise the steps of: receiving a second current blood glucose value of the user after the recommended compensated insulin bolus amount and the recommended first corrected insulin bolus amount are dispensed to the user, but before the expiration of the post-prandial rest time period and before the expiration of the first corrected rest time period; determining a second recommended corrected insulin bolus amount if the second current blood glucose value exceeds the first modified blood glucose target; calculating a second difference as the second current blood glucose value minus the first modified blood glucose target; and if the second difference is positive, increasing the blood glucose target by the second difference to produce a second modified blood glucose target at a second correction stop time period.

Alternatively, the method may further comprise the steps of: receiving a second current blood glucose value of the user after the recommended compensated insulin bolus amount and the recommended first corrected insulin bolus amount are dispensed to the user, and after expiration of the post-prandial rest time period, but before expiration of the first corrected rest time period; decreasing the first modified glycemic target by the postprandial increase value to produce a second modified glycemic target; determining a second recommended corrected insulin bolus amount if the second current blood glucose value exceeds the second modified blood glucose target; calculating a second difference as a second current blood glucose value minus a second modified blood glucose target; and if the second difference is positive, increasing the second modified blood glucose target by the second difference to produce a third modified blood glucose target at a second correction stop time period.

These and other features of the present invention will be apparent from the following description of illustrative embodiments.

Drawings

FIG. 1 is a block diagram of one illustrative embodiment of an insulin bolus recommendation system.

FIGS. 2A-2N and 2P-2Q are each interactive display screens that collectively form a graphical user interface illustrating one embodiment of a software algorithm that may be executed by the system of FIG. 1 for establishing initial operating parameters and limits for an insulin bolus recommendation software algorithm.

Fig. 3A and 3B show a flow chart of one illustrative embodiment of an insulin bolus recommendation software algorithm that may be executed by the system of fig. 1 for determining and recommending an insulin bolus amount.

FIG. 4A is an interactive display screen illustrating one embodiment of a graphical user interface for performing step 106 of the software algorithm of FIG. 3.

FIG. 4B is an interactive display screen illustrating one embodiment of a graphical user interface for performing steps 124 and 126 of the software algorithm of FIG. 3.

FIG. 4C is an interactive display screen illustrating one embodiment of another graphical user interface for performing steps 124 and 126 of the software algorithm of FIG. 3.

FIG. 4D is an interactive display screen illustrating one embodiment of yet another graphical user interface for performing steps 124 and 126 of the software algorithm of FIG. 3.

FIG. 4E is an interactive display screen illustrating one embodiment of a graphical user interface for performing step 134 of the software algorithm of FIG. 3.

FIG. 4F is an interactive display screen illustrating one embodiment of a graphical user interface for performing step 140 of the software algorithm of FIG. 3.

FIG. 5 is a flow diagram of one illustrative embodiment of a software routine for performing step 112 of FIG. 3.

FIG. 6 is a flow diagram of one illustrative embodiment of a software routine for performing step 114 of FIG. 3.

FIG. 7 is a flow diagram of one illustrative embodiment of a software routine for performing step 116 of FIG. 3.

FIGS. 8A and 8B show a flowchart of one illustrative embodiment of a software routine for performing step 118 of FIG. 3.

FIG. 9 is a flow diagram of one illustrative embodiment of a software routine for performing step 120 of FIG. 3.

FIG. 10 is a graph of blood glucose and an effective correction bolus versus time illustrating one example of the operation of the insulin bolus recommendation algorithm of FIG. 3.

FIG. 11 is a graph of blood glucose and correction/compensation bolus versus time illustrating another example of the operation of the insulin bolus recommendation algorithm of FIG. 3.

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

Referring now to FIG. 1, a block diagram of one illustrative embodiment of an insulin bolus recommendation system 10 is shown. In the illustrated embodiment, the insulin bolus recommendation system 10 includes a bolus recommendation unit 12, the bolus recommendation unit 12 having at least one control circuit 14, the control circuit 14 being electrically connected to a visual display unit 16 and also electrically connected to a data entry unit 18. While the control circuit 14 may alternatively be any single electronic circuit or collection of electronic circuits capable of operating as described below, the control circuit 14 illustratively may be a conventional, microprocessor-based control computer capable of executing one or more software algorithms. In some embodiments, the control circuit 14 may be electrically connected to a conventional memory cell 20 as shown in dashed lines. The visual display unit may be or may include any conventional display screen including, but not limited to, a Cathode Ray Tube (CRT) display, a Liquid Crystal Display (LCD), a plasma display, a monochrome or multi-color monitor, a touch-sensitive data entry screen, and the like. The data entry unit 18 may be or include any conventional data entry device including, but not limited to, a keyboard or keypad, a mouse or similar pointing device, one or more coded or uncoded touch switches associated with the display unit 16, a voice activated data entry device, or the like.

In some embodiments, the insulin bolus recommendation system 10 may also include an additional bolus recommendation unit 30 as shown in dashed lines in FIG. 1. The unit 30 may include a control circuit 32, the control circuit 32 being electrically connected to a visual display unit 34 and also to a data entry unit 36, wherein the control circuit 32, the display unit 34 and the data entry unit 36 may be provided in any of the forms described below with respect to the bolus recommendation unit 12. The control circuit 32 may also be electrically connected to a conventional memory unit 38. In this embodiment, bolus recommendation unit 12 and bolus recommendation unit 30 may each be configured to share information via a wired connection 40 comprising one or more signal paths physically connecting the two units, via a wireless signal path 42 such as a radio signal or cellular telephone link, and/or via the World Wide Web (WWW)44, each of which employs conventional techniques.

The insulin bolus recommendation system 10 is configured to determine and recommend that a particular insulin bolus amount be injected into the blood stream of a user of the system 10 one or more times according to an insulin bolus recommendation protocol implemented in the system 10 as one or more executable software algorithms. The physical structure of the insulin bolus recommendation system 10 for executing such software algorithms and for communicating useful information between the system 10 and the user may take a variety of forms. In one illustrative embodiment, for example, the bolus recommendation system 10 includes only the bolus recommendation unit 12, the bolus recommendation unit 12 being implemented as a conventional Personal Computer (PC), a laptop or notebook computer, a Personal Data Assistant (PDA), or the like, or as a handheld, laptop or desktop dedicated bolus recommendation unit. In any of these cases, the bolus recommendation unit 12 includes a memory unit 20 having a number of executable software algorithms stored therein, and the control circuit 14 is operable to execute these software algorithms to determine and recommend that a particular insulin bolus amount be injected into the blood stream of the user one or more times in accordance with an insulin bolus recommendation protocol as will be described in detail below. In this embodiment, the display unit 16 is controlled by the control circuit 14 under the direction of software algorithms to communicate information to the user and to prompt the user for information that he may input via the data entry unit 18.

In another illustrative embodiment, the insulin bolus recommendation system 10 includes a bolus recommendation unit 12 and a bolus recommendation unit 30. As an example of this embodiment, the bolus recommendation unit 12 may be a PDA or a dedicated bolus recommendation unit as described above, while the bolus recommendation unit 30 may be a PC, laptop or notebook computer. In this embodiment, unit 12 may communicate with unit 30 either via wireless interface 42 or via wired interface 40, which wireless interface 42 or wired interface 40 may be electrically connected to a PDA or a dedicated bolus recommendation unit holder (cradle) configured to receive unit 12 and electrically connect unit 12 in data communication with unit 30. In this example, the memory units 20 and 38 of the units 12 and 30, respectively, may each have a number of software algorithms stored therein, and the user may use the bolus recommendation unit 12 as a mobile insulin bolus recommendation unit and/or the bolus recommendation unit 30 as a fixed insulin bolus recommendation unit. In this case, the user will currently maintain the database for each unit 12 and 30 by periodically synchronizing the databases of units 12 and 30 via wired or wireless interfaces 40 or 42, respectively.

As another example of an embodiment of an insulin bolus recommendation system 10 that includes a bolus recommendation unit 12 and a bolus recommendation unit 30, the bolus recommendation unit 12 may be a PDA, PC, laptop or notebook computer, cellular telephone, or any other unit or device capable of accessing WWW 44. In this example, the bolus recommendation unit 12 need not have a large number of software algorithms stored in the memory unit 20, and need not include the memory unit 20 at all. In this example, the bolus recommendation unit 30 may be a remote computer or a conventional web server that is also configured to access WWW44 and has a number of software algorithms stored in the storage unit 38. The control circuit 32 of the remote computer or web server 30 is operable in this example to execute a number of software algorithms based on information provided by the user via the bolus recommendation unit 12 over WWW 44. In this particular embodiment, the user and/or the healthcare provider may access a web page or website controlled by the bolus recommendation unit 30 and provide the initial operating parameters and/or limits of the insulin bolus recommendation protocol to the control circuit 32. The user may then and thereafter access a web page or website and enter current blood glucose information, and based on the current blood glucose information according to an insulin bolus recommendation protocol, which will be described in detail below, the control circuitry 32 may then determine and recommend via the web page or website that a particular insulin bolus amount be injected into the user's bloodstream one or more times.

In this particular embodiment, the insulin bolus recommendation software algorithm is thus located in the remote computer or web server 30, and in this regard, the bolus recommendation unit 12 need only include sufficient hardware to be able to provide the current blood glucose information to a web page or web site and to be able to view recommendations generated on the web page or web site through the remote computer or web server 30. As a practical matter, it may also be desirable in this embodiment to provide the bolus recommendation unit 12 with the storage unit 20 and store a large number of bolus recommendation software algorithms therein so that the bolus recommendation unit 12 can independently execute these software algorithms when it is not possible or practical to access the WWW44 and/or an appropriate web page or website. It may also be desirable in such embodiments to provide for synchronization of the remote and/or network-based database with the database stored in the memory unit 20 of the bolus recommendation unit 12.

It should be understood that the insulin bolus recommendation system 10 may be configured to cooperate with a blood glucose meter or other automatic blood glucose determination unit and/or an insulin pump or other automatic insulin dosing or dispensing unit. In embodiments in which a blood glucose meter or other automatic blood glucose determining unit is included with the insulin bolus recommendation system 10, the control computer 14 may be configured to cause such unit to automatically generate current blood glucose information that the system 10 may subsequently use, using conventional techniques, as will be described in detail below, to determine and recommend the delivery of one or more insulin bolus quantities. In embodiments in which an insulin pump or other automatic insulin dosing unit is included with the insulin bolus recommendation system 10, the control computer 14 may be configured to cause such unit to automatically dispense the recommended insulin bolus amount to the user using conventional techniques.

As described above, the insulin bolus recommendation system 10 shown in FIG. 1 is operable to execute a plurality of software algorithms for determining and recommending one or more specific insulin bolus quantities to be administered to the blood stream of a user in accordance with an insulin bolus recommendation protocol. At least one of these software algorithms is configured to be established based on user and/or healthcare provider input, initial operating parameters and limits used by the insulin bolus recommendation software algorithm. Referring now to FIGS. 2A-2N and 2P-2Q, a plurality of interactive display screens are shown that collectively form a graphical user interface illustrating one embodiment of a software algorithm that may be executed by the system 10 of FIG. 1 for establishing initial operating parameters and limits for use by the insulin bolus recommendation software algorithm. It should be appreciated that the processes shown in fig. 2A-2N and 2P-2Q are implemented in one or more software algorithms stored in one or both of the memory units 20 and 38 and executable by the control circuits 14 and/or 32, and that the control circuits 14 and/or 32 are configured to control the displays 16 and/or 34, respectively, in a conventional manner to produce the graphical information shown in fig. 2A-2N and 2P-2Q. It will also be appreciated that the user prompts displayed on displays 16 and/or 32 are responded to by a user of system 10 by entering the appropriate information in a conventional manner via data entry units 18 and/or 36, respectively.

In any event, the software algorithm or algorithms executed by the system 10 of FIG. 1 for establishing the initial operating parameters and limits used by the insulin bolus recommendation software algorithm are shown in FIGS. 2A-2N and 2P-2Q as being implemented with a bolus recommendation unit 12 provided in the form of a conventional or dedicated PDA. Those of ordinary skill in the art will recognize that the illustrative processes shown in fig. 2A-2N and 2P-2Q may alternatively be implemented using the bolus recommendation unit 12 and/or the bolus recommendation unit 30 provided in any one or more of the physical forms described above.

Referring now to FIG. 2A, one or more software algorithms for establishing initial operating parameters and limits used by the insulin bolus recommendation software algorithm begin with selecting a main settings screen 50. The main settings screen 50 displays the word "set BRS" in the upper left hand portion of the screen, indicating selection of a bolus recommendation system setting procedure. The system 10 includes a real time clock and the current time is indicated in the upper right hand portion of the screen 50. Some embodiments of system 10 may include conventional circuitry for automatically adjusting or changing the time setting of the real-time clock, while other embodiments may allow a user to change the time setting of the real-time clock. It should be understood that the various forms of the system 10 may be configured to handle such automatic changes in the time setting of the user or real-time system clock in different ways. For example, in embodiments of the system 10 equipped to record or validate time change events and time changes, one or more algorithms may be included to track such time change events and update time-stamped data and/or other time-sensitive information with the time change information. Also, in embodiments of the system 10 equipped to record or confirm time change events but not time change amounts, one or more algorithms may be included to track such time change events, to prompt the user for information about the time change amounts, and to update time-stamped data and/or other time-sensitive information with the time change information. Any such algorithm or algorithms will be within the ability of a skilled software programmer.

The main portion of the screen 50 includes a plurality of functions, some of which may be immediately selectable, while others are not. In the example shown in fig. 2A, the "initialize" function is highlighted for selection, while the remaining features are outlined by dashed boxes indicating that these features have not been selected. In general, the example initialization process shown in FIGS. 2A-2N and 2P-2Q requires the various features shown in FIG. 2A to be performed continuously, and thus features subsequent to the currently highlighted feature may not be selected until all preceding features have been selected and performed. It should be understood, however, that such a continuous feature execution process is shown in FIGS. 2A-2N and 2P-2Q by way of example only, and that the one or more software algorithms for establishing the initial operating parameters and limits used by the insulin bolus recommendation software algorithm may alternatively be implemented in a discontinuous process.

When the user selects the "initialize" feature shown in FIG. 2A, the "calculate factor" feature then becomes highlighted as shown in display 52 shown in FIG. 2B. When the "calculate factor" feature is then selected, as shown in FIG. 2C, a "calculate factor" display 54 is generated. Whenever the "calculation factor" display 54 is selected, the display 54 displays the word "calculation factor" in the upper left-hand portion of the screen, indicating the selection of the calculation factor setting process.

The processes shown in fig. 2A-2N and 2P-2Q provide for the establishment of initial operating parameters and limits for each of a plurality of time blocks, wherein a user may divide any day into any number of time blocks (up to "N", e.g., N-6). For each time block, the user may input to the display 54 an upper glycemic target (BGU), a lower glycemic target or hypoglycemic alert value (BGL), a Meal Factor (MF), and a blood glucose lowering to insulin ratio or insulin sensitivity value (IS). The upper blood glucose target (BGU) corresponds to a desired target blood glucose level, the hypoglycemic alert value (BGL) corresponds to a blood glucose threshold below which the system will generate a hypoglycemic alert, as described in more detail below with reference to FIG. 4C, the Meal Factor (MF) corresponds to a user-specific insulin-to-carbohydrate ratio, and the Insulin Sensitivity (IS) corresponds to a user-specific blood glucose lowering-to-insulin unit ratio. Such calculation factors are typically established by the healthcare provider and communicated to the user of the system 10 so that the user typically has these factors and/or a set of factors for various time blocks throughout the day. It should be understood that the particular calculation factor display 54 shown in FIG. 2C is provided by way of example only, and that the display 54 may alternatively include more or fewer calculation factors that require user input. In any case, the user may modify any information required by the display 54 by selecting the appropriate up or down arrow shown on the right side of the display 54. One or more of the calculation factors shown in display 54 may have default values, while other factors may be reset to zero with each new selection of display 54.

When the user has selected the appropriate value for the calculation factor shown in display 54, the user selects the "accept" icon, and the "set BRS" display 56 shown in FIG. 2D is then generated with the "time block" feature highlighted. When the user selects the "time block" feature, a "time block overview" display 58 is generated as shown in FIG. 2E. Whenever the "time block" display 58 is selected, the display 58 displays the word "time block" in the upper left hand portion of the screen, indicating the selection of the time block setting process. The "time block overview" display 58 allows the user to divide a day into any number (up to six in the illustrated embodiment) of time blocks, where the user may then use the display 54 shown in FIG. 2C to set a specific glycemic upper bound target (BGU), hypoglycemic alert (BGL), eating factor (MF), and Insulin Sensitivity (IS) value for each defined time block.

When the upper glycemic limit target (BGU), the hypoglycemic alert value (BGL), the Meal Factor (MF), and the Insulin Sensitivity (IS) values have been established for each of the defined time blocks by repeatedly executing the displays 54-58, a "set BRS" display 60 shown in FIG. 2F IS generated in which the "general parameters" feature IS highlighted. When the user selects the "general parameters" feature, the "general parameters" display 62 of FIG. 2G is generated. Display 62 allows the user to enter a hyperglycemic alert value (BGH) corresponding to a blood glucose level above which the system 10 displays a hyperglycemic alert message to the user, as will be described in more detail below with reference to FIG. 4D.

When the user has selected the appropriate hyperglycemic alert value (BGH), the user selects the "Accept" icon and the "general parameters" display 64 of FIG. 2H is generated. Display 64 allows the user to select a hypoglycemic alert value (BGA) that corresponds to a blood glucose level below which system 10 displays a hypoglycemic alert message to the user, as will be described more fully herein with reference to FIG. 4B. When the user has selected the desired hypoglycemic alarm value (BGA), the user selects the "Accept" icon and the "general parameters" display 66 of FIG. 2I is generated. After a meal, the blood glucose level will generally increase even if an appropriate insulin bolus is administered before or during the meal. Display 66 allows the user to enter a maximum post-prandial blood glucose increase value (Δ PP) corresponding to the maximum post-prandial blood glucose increase above which system 10 will determine and recommend an additional correction insulin bolus amount. When the user has selected an appropriate value for the maximum post-prandial blood glucose increase value (Δ PP), the user selects the "Accept" icon and the "general parameters" display 68 of FIG. 2J is generated.

Display 68 allows the user to enter a post-meal stop time or duration (TPP) that corresponds to the post-meal duration, wherein the rules established by display 66 are applied. When the user has selected the appropriate value for the post-prandial stop time or duration (TPP), the user selects the "Accept" icon and the "general parameters" display 70 of FIG. 2K is generated.

Display 70 allows the user to specify a carbohydrate intake Threshold (TCI) above which the rules established by displays 66 and 68 are applied only. After the user has selected an appropriate value for the carbohydrate intake Threshold (TCI), the user selects the accept icon and the general parameters display 72 of fig. 2L is generated.

Repeated insulin bolus corrections for a single, nonphage-related blood glucose increase may result in hypoglycemia, and the display 72 thus allows the user to select a correction insulin bolus stop time or duration (LOT) during which the system 10 will not determine and recommend additional correction insulin boluses from the single blood glucose rise event. After selecting the appropriate corrected insulin bolus stop time or duration (LOT), the user selects the "accept" icon and the "set BRS" display 74 of FIG. 2M is generated. It should be understood that the particular "general parameters" required for displays 62-72 shown in fig. 2G-2L, respectively, are provided by way of example only, and that the "general parameters" display may alternatively include more or fewer general parameters that require user input.

Display 74 indicates that the "compute factor", "time block", and "general parameters" features have been initialized, and that the "optional parameters" feature may be selected subsequently. If the user selects the "optional parameters" feature, an "optional parameters" display 76 of FIG. 2M is generated. Display 76 allows the user to preset a number (e.g., up to three) "adjustment levels" for certain activities for which the corrected insulin bolus value recommended by system 10 may be automatically modified. If the user selects the "YES" icon, a first "selectable parameter" display 78 of "adjust level 1/3" is generated as shown in FIG. 2P. Within the display 78, the user is allowed to define a first adjustment level and define an insulin bolus adjustment percentage corresponding to the defined first adjustment level. After the user defines the first adjustment level and the accompanying insulin bolus modification percentage in the display 78, the user selects the "accept" icon and generates another "selectable parameter" display. For example, FIG. 2Q shows a third "selectable parameter" display 80 for "adjustment level 3/3" wherein the user is allowed to define a third adjustment level and a corresponding insulin bolus adjustment percentage. In the illustrated example, the user has defined the third adjustment level as the "driving" level, and has specified a 50% reduction in the recommended correction insulin bolus amount while the user is engaged in driving activity. This completes the initialization process when the user has properly defined and selected various adjustment levels, and is then ready to execute the insulin bolus recommendation algorithm. It should be understood that the particular "adjustment levels" required for the three "selectable parameter" displays and the displays 76-80 shown in fig. 2A-2N and 2P-2Q, respectively, are provided by way of example only, and that the "selectable parameter" displays may alternatively include more, fewer, and/or different selectable parameters requiring user input.

Those of ordinary skill in the art will recognize that the aforementioned setup or initialization procedures shown in FIGS. 2A-2N and 2P-2Q represent one example insulin bolus recommendation system initialization or setup procedure, and that steps may be added to or deleted from the illustrated procedures without detracting from the scope of the claims.

Referring now to fig. 3A and 3B, a flow diagram of one illustrative embodiment of an insulin bolus recommendation software algorithm 100 for determining and recommending an insulin bolus amount is shown. As with the insulin bolus recommendation system initialization process shown in FIGS. 2A-2N and 2P-2Q, the insulin bolus recommendation software algorithm 100 of FIG. 3A will be described as being implemented with the insulin bolus recommendation unit 12 and executed by the control circuit 14, wherein the insulin bolus recommendation unit 12 is provided in the form of a conventional PDA or a handheld, dedicated insulin bolus recommendation unit, although those of ordinary skill in the art will recognize that the algorithm 100 may alternatively be implemented with the bolus recommendation unit 12 and/or the bolus recommendation unit 30 provided in any one or more of the physical forms described above.

In any case, the algorithm 100 begins at step 102 and, at step 104, the control circuit 14 determines whether a setup process (e.g., the insulin bolus recommendation system initialization or setup process shown in FIGS. 2A-2N and 2P-2Q) is complete. If not, execution of the algorithm 100 proceeds to step 146, and at step 146, the algorithm 100 is terminated. On the other hand, if the control circuit 14 determines at step 104 that the setup process has been completed, algorithm execution advances to step 106 where the control circuit 14 is operable to obtain a Blood Glucose Measurement (BGM) and a Carbohydrate Estimate (CE) at step 106. Referring to FIG. 4A, an interactive display 80 is shown illustrating one embodiment of a graphical user interface displayed on the display unit 16 of the insulin bolus recommendation unit 12 for performing step 106 of the algorithm 100. The display 80 shown in fig. 4A allows the user to enter a blood glucose measurement value (BGM) corresponding to the user's blood glucose level, which is measured within a certain time period (e.g., five minutes) of entering blood glucose measurement data into the algorithm 100. The user may obtain a blood glucose measurement value (BGM) via any conventional blood glucose measurement device and/or technique. Alternatively, an automatic blood glucose determination unit of the type described above may determine the blood glucose value of the user at step 106 and provide the corresponding blood glucose measurement value (BGM) directly to the algorithm 100. In any case, the display 80 also prompts the user to enter an estimated amount of Carbohydrates (CE) corresponding to the amount of carbohydrates consumed in a subsequent meal or snack. After the user enters the measured blood glucose level (BGM) and the estimated carbohydrate amount (CE), if any, the user selects the accept icon and execution of the algorithm 100 proceeds from step 106 to step 108 where the control circuit 14 is operable to retrieve the setting parameters for the current time interval from the insulin bolus recommendation database stored in the memory unit 20 at step 108. The insulin bolus recommendation database will typically include at least the initialization or setting parameters described above with reference to FIGS. 2A-2N and 2P-2Q, as well as information regarding previous blood glucose measurements, previously recommended insulin boluses, stop timer values, and the like.

From step 108, execution of algorithm 100 proceeds to step 110, where, at step 110, control circuit 14 is operable to retrieve the current values of the Bolus Trigger (BT), the blood glucose upper limit target (BGU), the correction bolus stack, the Meal Bolus Timestamp (MBTS), and the previous meal activity flag (PMA) from memory unit 20. In the first execution of the algorithm 100, the Bolus Trigger (BT) will be set equal to the upper blood glucose target (BGU), the Meal Bolus Timestamp (MBTS) will be zero, the previous meal activity flag (PMA) will be "false", and the correction bolus stack will be emptied. As execution of algorithm 100 progresses and/or through repeated execution of algorithm 100 as will become more apparent from the detailed description of the remainder of algorithm 100 below, any one or more of these values may change and the correction bolus stack may be populated with correction bolus information.

Execution of the algorithm 100 proceeds from step 110 to step 112 where the control circuit 14 is operable to execute a correction bolus stack processing routine at step 112. Referring to fig. 5, a flowchart of one illustrative embodiment of a collect bolus stack processing routine invoked by step 112 of the algorithm is shown. In the illustrated embodiment, the correction bolus stack processing routine 112 begins at step 150, and at step 150 the control circuit 14 is operable to execute each of the steps 152 and 156 between steps 150 and 158 for each entry in the correction bolus stack. In at least the first execution of the algorithm 100, the correction bolus stack will be emptied as described above, and the routine 112 will therefore proceed directly to step 162, which step 162 returns execution of the routine 112 to the algorithm 100.

Whenever a corrected insulin bolus amount is determined and recommended by the insulin bolus recommendation system 10 under the direction of the software algorithm 100, the control circuit 14 is operable to establish a Corrected Bolus Time Stamp (CBTS) corresponding to the actual time at which the corrected insulin bolus amount is determined, recommended, and/or approximately dispensed to the user. Thereafter, the insulin bolus recommendation system 10 is "stopped" from determining and recommending other insulin bolus amounts for which to correct the insulin bolus quantity at the time of the correction insulin bolus stop time period (LOT) CETS recommending (and presumably dispensing). As will be described in greater detail below with reference to FIG. 8, the insulin bolus recommendation system 10 is operable to implement this "stop" feature by increasing the blood glucose upper limit target (BGU) by the calculated blood glucose amount (Δ BG). Thus, each entry in the correction bolus stack will have a Correction Bolus Time Stamp (CBTS) and a blood glucose increase value (Δ BG) associated therewith.

At step 152, the control circuit 14 is operable to compare the sum of the Correction Bolus Time Stamp (CBTS) and the correction insulin bolus stop time period (LOT) to the current time of one of the entries in the correction bolus stack. If the sum of the selected entry's CBTS and LOT is later than the current time, the associated Δ BG for that stack entry is subtracted from the current value of the glycemic upper bound target (BGU) and also from the current value of the Bolus Trigger (BT), and then the entire stack entry is marked for deletion or removal. After all entries in the correction bolus stack are likewise processed, execution of routine 112 proceeds to step 160 where all correction bolus entries in the correction bolus stack that are flagged for removal are removed or deleted from the correction bolus stack at step 160. Thereafter, at step 162, execution of the routine 112 returns to step 112 of the algorithm 100.

It should be understood that the correction bolus stack processing routine illustrated in fig. 5 is provided by way of example only, and that the routine of fig. 5 may alternatively be configured to process a set of correction bolus stack entries according to other known software techniques. As one example, a set of Corrected Bolus Time Stamps (CBTS) and associated blood glucose increase values (Δ BG) may be entered into a regular queue when they occur. The routine of fig. 5 may then be configured to process not every entry in the correction bolus queue, but only the latest queue entry for which CBTS + LOT is later than the current time. One of ordinary skill in the art will recognize other software techniques for processing the set of Corrected Bolus Time Stamps (CBTS) and associated blood glucose increase values (Δ BG) in the manner just described, and any such alternative data processing techniques are considered to fall within the scope of the appended claims.

After completing step 112, execution of algorithm 100 proceeds to step 114, where control circuit 14 is operable to execute a meal bolus time processing routine at step 114. Referring now to FIG. 6, a flowchart of one illustrative embodiment of a meal bolus time processing routine invoked by step 114 of algorithm 100 is shown. If a meal compensation insulin bolus amount is determined and recommended by the insulin bolus recommendation system 10 under the direction of software algorithm 100, the control circuit 14 is operable to establish a Meal Bolus Time Stamp (MBTS) corresponding to the actual time at which the meal compensation insulin bolus amount was determined, recommended, and/or approximately dispensed to the user. Thereafter, the insulin bolus recommendation system 10 is "stopped" during a post-prandial stop time period (TPP) from determining and recommending other insulin bolus amounts for post-prandial blood glucose increases. As described in more detail below with reference to FIG. 8, the insulin bolus recommendation system 10 is operable to implement this postprandial "stop" feature by increasing the blood glucose upper limit target (BGU) by the calculated postprandial blood glucose increase value (Δ BGPP).

In the illustrated embodiment, the meal bolus time processing routine begins at step 170, and at step 170 the control circuit 14 is operable to determine whether a Meal Bolus Timestamp (MBTS) is set, and if so, whether the sum of the Meal Bolus Timestamp (MBTS) and the post-meal stop time period (TPP) is later than the current time. If so, the control circuit 14 is operable at step 172 to subtract the post-prandial blood glucose increase value (Δ BGPP) from the current value of the Bolus Trigger (BT), and then at step 174 to set the post-prandial blood glucose increase value (Δ BGPP) equal to zero. Thereafter at step 176, the control circuit 14 is operable to set the previous meal activity flag (PMA) equal to "false" and then clear the Meal Bolus Timestamp (MBTS), e.g. by setting MBTS to zero. Execution of the meal bolus time processing routine proceeds from step 176 and from the "N" branch of step 170 to step 178, where execution of the meal bolus time processing routine is returned to step 114 of algorithm 100 at step 178.

After completing step 114, execution of algorithm 100 proceeds to step 116 where control circuit 14 is operable to execute a meal compensation bolus processing routine at step 116. Referring now to FIG. 7, a flowchart of one illustrative embodiment of a meal compensation bolus processing routine invoked by step 116 of algorithm 100 is shown. In the illustrated embodiment, the meal compensation bolus processing routine begins at step 180 and, at step 180, the control circuit 14 is operable to determine whether the estimated carbohydrate amount (CE) established at step 106 of the algorithm 100 is greater than zero. If so, execution of the routine advances to step 182, where the control circuit 14 is operable to calculate the recommended meal compensation insulin bolus amount (MB) as the product of the Carbohydrate Estimate (CE) and the Meal Factor (MF), step 182. Thereafter at step 184, the control circuit 14 is operable to determine whether the estimated carbohydrate amount (CE) is greater than a carbohydrate intake Threshold (TCI) established as part of the setup or initialization process described above with reference to FIGS. 2A-2N and 2P-2Q. If so, execution of the routine advances to step 186 where the control circuit 14 is operable to set the post-prandial blood glucose increase value (Δ BGPP) equal to the maximum post-prandial blood glucose increase value (Δ PP) established as part of the setup or initialization process described above with respect to FIGS. 2A-2N and 2P-2Q. Thereafter at step 188, the control circuitry is operable to set a Meal Bolus Timestamp (MBTS) equal to the current time period. If the control circuit 14 determines at step 180 that the estimated carbohydrate amount (CE) is not greater than zero, the control circuit 14 is operable to set the meal compensation insulin bolus amount (MB) equal to zero. Execution of the routine proceeds from steps 188 and 190 and from the "N" branch of step 184 to step 192, where execution of the meal compensation bolus processing routine returns to step 116 of algorithm 100 at step 192.

After completing step 116, execution of the algorithm 100 proceeds to step 118, where the control circuit 14 is operable to execute a correction bolus processing routine at step 118. Referring now to fig. 8A and 8B, a flowchart of one illustrative embodiment of a correction bolus processing routine invoked by step 118 of algorithm 100 is shown. In the illustrated embodiment, the correction bolus processing routine begins at step 200, and at step 200, the control circuit 14 is operable to compare the measured blood glucose value (BGM) determined at step 106 of the algorithm 100 to a hypoglycemic alarm value (BGA) established as part of the setup or initialization process described above with reference to FIGS. 2A-2N and 2P-2Q. If the control circuit 14 determines at step 200 that BGM is less than or equal to BGA, execution of the routine proceeds to step 202 where the control circuit 14 selects the hypoglycemic alarm message shown in the example in display 82 of FIG. 4B as alert at step 202. Thereafter, the control circuit 14 is operable to set the corrected insulin bolus amount (CB) to zero at step 204, and then set the meal compensation insulin bolus amount (MB) equal to zero at step 206. Following step 206, execution of the correction bolus processing routine advances to step 208 where, at step 208, the control circuit 14 is operable to set the Bolus Trigger (BT) to the upper blood glucose limit target (BGU).

If the control circuit 14 determines at step 200 that the measured blood glucose value (BGM) is greater than the hypoglycemic alert value (BGA), execution of the correction bolus processing routine advances to step 210 where the control circuit 14 is operable to compare the measured blood glucose value (BGM) to the hypoglycemic alert value (BGL) at step 210. If the control circuit 14 determines at step 210 that BGM is less than or equal to BGL, execution of the correction bolus routine proceeds to step 212 where, at step 212, the control circuit 14 sets the hypoglycemic alert message shown in the example in display 84 of FIG. 4C to alert. Thereafter at step 214, the control circuit 14 is operable to calculate a blood glucose increase value (Δ BG) as the measured blood glucose value (BGM) minus a hypoglycemic alert value (BGL). Thereafter at step 216, the circuit 14 IS operable to calculate the corrected insulin bolus amount (CB) as a ratio of Δ BG to an insulin sensitivity value (IS) established as part of the setup or initialization process described above with reference to FIGS. 2A-2N and 2P-2Q.

After step 216, the correction bolus processing routine advances to step 218 where the control circuit 14 is operable to determine the state of the previous meal activity flag (PMA) at step 218. If the control circuit 14 determines at step 218 that the previous meal activity flag (PMA) is not "true", execution of the routine proceeds to step 220 where the control circuit 14 is operable to determine at step 220 whether the Carbohydrate Estimate (CE) is greater than a carbohydrate intake Threshold (TCI) established as part of the setup or initialization process described above with reference to FIGS. 2A-2Q. If so, the control circuit 14 is operable to set the previous meal activity flag (PMA) to "true" at step 222, and thereafter set the Bolus Trigger (BT) to the maximum of the sum of the blood glucose upper limit target (BGU) and the measured blood glucose value (BGM) and the post-prandial blood glucose increase value (Δ BGPP) at step 224. On the other hand, if the control circuit 14 determines at step 220 that the estimated carbohydrate amount (CE) is not greater than the carbohydrate intake Threshold (TCI), execution of the routine advances to step 226 where the control circuit 14 is operable to set the Bolus Trigger (BT) to the upper blood glucose limit target (BGU) at step 226.

If the control circuit 14 determines at step 210 that the measured blood glucose value (BGM) is greater than the hypoglycemic alert value (BGL), execution of the correction bolus processing routine advances to step 228 where the control circuit 14 is operable to determine at step 228 whether the measured blood glucose value (BGM) is greater than the hyperglycemic alert value (BGH). If so, the control circuit 14 selects the hyperglycemic alert message shown in the example in display 86 of FIG. 4D as alert at step 230. Execution of the correction bolus processing routine advances from step 230 and from the "N" branch of step 228 to step 232, where, at step 232, the control circuit 14 is operable to compare the measured blood glucose value (BGM) to the current value of the Bolus Trigger (BT). If the control circuit 14 determines at step 232 that BGM is greater than BT, execution of the routine proceeds to step 234.

At step 234, the control circuit 14 is operable to set the blood glucose increase value (Δ BG) equal to the measured blood glucose value (BGM) minus the current value of the Bolus Trigger (BT). The control circuit 14 IS further operable at step 234 to calculate a corrected insulin bolus amount (CB) as a ratio of the blood glucose increase value (Δ BG) and the insulin sensitivity value (IS). Control circuit 14 is also operable at step 234 to input the current time in the form of a Correction Bolus Time Stamp (CBTS) and the current blood glucose increase value (Δ BG) into the correction bolus stack as described above with reference to fig. 5. Finally, the control circuit is operable at step 234 to set the upper glucose limit target (BGU) to the sum of the current upper glucose limit target (BGU) and the blood glucose increase value (Δ BG). If the control circuit 14 determines at step 232 that the measured blood glucose value (BGM) is not greater than the current value of the Bolus Trigger (BT), execution of the routine advances to step 236 where the control circuit 14 is operable to set the corrected insulin bolus amount (CB) equal to zero at step 236.

After either of steps 234 and 236, execution of the correction insulin bolus processing routine advances to step 238 where the control circuit 14 is operable to determine the state of the previous meal activity flag (PMA) at step 238. If the control circuit 14 determines at step 238 that the previous meal activity flag (PMA) is "true", then execution of the routine proceeds to step 240 where, at step 240, the control circuit 14 is operable to calculate the current value of the Bolus Trigger (BT) as the sum of the upper blood glucose limit target (BGU) and the post-prandial blood glucose increase value (Δ BGPP). On the other hand, if the control circuit 14 determines at step 238 that the previous meal activity flag (PMA) is not "true", execution of the routine proceeds to step 220. The "Y" branch of steps 208, 226 and 240 and step 218 proceeds to step 242 where, at step 242, execution of the correction bolus processing routine returns to step 118 of algorithm 100.

After completing step 118, execution of the algorithm 100 advances to step 120 where the control circuit 14 is operable to execute a total insulin bolus processing routine at step 120. Referring now to FIG. 9, a flowchart of one illustrative embodiment of a total insulin bolus processing routine invoked by step 120 of the algorithm 100 is shown. In the illustrated embodiment, the total insulin bolus processing routine begins at step 250 and, at step 250, the control circuit 14 is operable to calculate the total insulin bolus amount (TB) as the sum of the meal compensated insulin bolus amount (MB) and the corrected insulin bolus amount (CB). Thereafter at step 252, the control circuit 14 is operable to determine whether the total insulin bolus amount (TB) is less than zero. If so, execution of the routine advances to step 254 where the control circuit 14 is operable to set the total insulin bolus amount (TB) equal to zero at step 254. Execution of the total insulin bolus processing routine proceeds from step 254 and also from the "N" branch of step 252 to step 256, where execution of the total insulin bolus processing routine returns to step 120 of algorithm 100 at step 256.

From step 120, the algorithm 100 proceeds to step 122, where the control circuit 14 is operable to determine whether the correction bolus processing routine invoked by step 118 of the algorithm 100 has selected any alerts or alarms for display at step 122. If so, execution of the algorithm 100 proceeds to step 124, and at step 124 the control circuit 14 is operable to display the selected alert or alarm as indicated by the various example alert and alarm messages shown in FIGS. 4B-4D. Each of the alerts or alarm message displays 82, 84, and 86 includes an "OK" icon that the user selects at step 126 of the algorithm 100 to confirm the alarm or alert. Thereafter, at step 128, the control circuit 14 saves the time stamp of the alert or alarm confirmation to the memory unit 20. Thereafter at step 130, the control circuit 14 is operable to determine whether the alert displayed at step 124 corresponds to a low blood glucose or hypoglycemic alarm as shown in the display 82 of FIG. 4B. If so, execution of the algorithm 100 proceeds to step 132, at step 132, the control circuit 14 is operable to save the measured blood glucose value (BGM) and the accompanying alert or alarm message to a database stored in the memory unit 20.

On the other hand, if the control circuit 14 determines at step 130 that the alert message displayed at step 124 does not correspond to a hypoglycemic or hypoglycemic alarm, execution of the algorithm 100 proceeds to step 134 where the control circuit 14 is operable to display an initial insulin bolus recommendation calculated by the control circuit 14 at step 134. Referring to FIG. 4E, an interactive display 88 is shown, the interactive display 88 illustrating one embodiment of a graphical user interface displayed on the display unit 16 of the insulin bolus recommendation unit 12 for performing step 134 of the algorithm 100. In the graphical display 88 shown in FIG. 4E, the 11.4 units of total insulin bolus recommendation is shown as the sum of the recommended 10.4 units of the calculated meal compensation insulin bolus amount (MB) and the one unit recommendation of the calculated correction insulin bolus amount (CB). Also shown in display 88 is an adjustment selection area that allows the user to select any one or more of the predetermined insulin bolus modification adjustment levels 1-3 established as part of the setup or initialization process described above with reference to FIGS. 2A-2N and 2P-2Q. In the example shown in fig. 4E, a third level corresponding to a 50% insulin bolus reduction for "driving activity" is shown as selected.

Following step 134 of the algorithm 100, the user is provided with the options of "cancel", "return", "reset" and "accept" the initial results displayed in FIG. 4E at step 136, as shown graphically in FIG. 4E. If the user selects the "Cancel" icon, the algorithm 100 proceeds to step 146, and the algorithm 100 is terminated at step 146. If not, but the user selects "return," execution of the algorithm 100 returns to step 106 to prompt the user to obtain new blood glucose and estimated carbohydrate information. If instead, the user selects "reset", the algorithm 100 proceeds to step 138, and the control circuit 14 is operable to reset any modifications that the user has made to the information shown in the display 88 at step 138, and then redisplay the original initial results at step 134. After the user has modified the "adjust" information as desired, the user selects "accept" and the algorithm 100 proceeds to step 140 where the control circuit 14 is operable to display the final insulin bolus recommendation at step 140 as shown in the example of display 90 of FIG. 4F.

In the graphical display 90 shown in FIG. 4F, the total insulin bolus recommendation of 5.7 international units is shown as the sum of the recommended calculated meal compensation insulin bolus amount (MB) of 10.4 international units and the one international unit recommended calculated correction insulin bolus amount (CB) minus the "drive" adjustment percentage. Following step 140 of the algorithm 100, the user is provided with the options of "cancel", "return", and "accept" the final result shown in FIG. 4F at step 142, as shown graphically in FIG. 4F. If the user selects the "Cancel" icon, the algorithm 100 proceeds to step 146, and the algorithm 100 is terminated at step 146. If instead, the user selects "return", execution of the algorithm 100 returns to step 134, and the control circuit 14 is operable to again display the initial result at step 134. By selecting the "accept" icon, the user confirms that the recommended insulin dose displayed in the display 90 will be delivered to the user and that the current data set will be transferred to the database in the storage unit 20. Execution of the algorithm proceeds from the "accept" option of step 142 to step 144, at step 144 the control circuit is thus operable to save the current data set including the initial and final results and the updated operating parameters to the database stored in the storage unit 20. Execution of the algorithm 100 then proceeds from step 144 to step 146, where the algorithm 100 is terminated at step 146.

Example 1

With the aid of fig. 10, an example of the operation of the algorithm 100 will now be provided. In this example, the meal will not be ingested during the indicated period of time, and thus, the meal compensation insulin bolus will not be calculated or recommended. This example assumes that the initialization or setup process shown in fig. 2A-2N and 2P-2Q has been performed previously, resulting in the calculation factors, general parameters and optional parameters that are available during the indicated deadlines in this example and are shown in table 1 below:

TABLE 1

Factor or parameter	Value of
Factor or parameter	Value of	BGU	100mg/dl
BGA	60mg/dl	BGU	100mg/dl
BGA	60mg/dl	BGL	80mg/dl
BGH	200mg/dl	BGL	80mg/dl
BGH	200mg/dl	MF	1.0I.U./10gr. carbohydrate
IS	40mg/dl/I.U.	MF	1.0I.U./10gr. carbohydrate
IS	40mg/dl/I.U.	ΔPP	50mg/dl
TCI	10gr	ΔPP	50mg/dl
TCI	10gr	TPP	150min
LOT	120min	TPP	150min
LOT	120min	Level of regulation 1/3	0％
Level of regulation 2/3	0％	Level of regulation 1/3	0％
Level of regulation 2/3	0％	Level of regulation 3/3	0％

Referring now to fig. 10, a graph of correction bolus versus time illustrating blood glucose and activity for this example is shown. With the setup complete, the algorithm 100 prompts the user to enter the current Blood Glucose Measurement (BGM) and Carbohydrate Estimate (CE) at step 106. At time T0, the user obtains a Blood Glucose Measurement (BGM)₀) And therefore 160mg/dl of BGM is input in the display 80. Since no meals are ingested during the time interval shown in fig. 10, the user also enters a CE of 0gr in the display 80. Alternatively, the display 80 may have CE 0 as a default, in which case the user need only accept CE 0gr. at step 106. Thereafter, in step 108, control circuit 14 retrieves the parameter set corresponding to the information in table 1 from the database stored in storage unit 20. At step 110, control circuit 14 also retrieves a Bolus Trigger (BT), a blood glucose upper limit target (BGU), a Meal Bolus Timestamp (MBTS), and a previous meal activity flag (PMA), as well as correcting the current value of the bolus stack. For the first execution of the algorithm 100,BT-BGU-100 mg/dl, MBTS-0, PMA-false, and the correction bolus stack is emptied.

At step 112, control circuit 14 executes the correction bolus stack processing routine of FIG. 5. Since the correction bolus stack is emptied, execution of the routine returns to step 112 of algorithm 100. Thereafter, at step 114, the control circuit 14 executes the meal bolus time processing routine of FIG. 6. Since the Meal Bolus Time Stamp (MBTS) is zero (i.e., not "set"), step 170 of the meal bolus time processing routine proceeds directly to step 178, where execution of the routine returns to step 114 of algorithm 100.

At step 116, the control circuit 14 executes the meal compensation bolus processing routine of FIG. 7. Since the estimated carbohydrate amount (CE) entered by the user at step 106 is zero, step 180 of the meal compensation bolus processing routine proceeds to step 190 where the control circuit 14 sets the meal compensation insulin bolus amount (MB) equal to zero at step 190. Thereafter, at step 192, execution of the routine returns to step 116 of the algorithm 100.

At step 118, the control circuit 14 executes the correction bolus processing routine of FIGS. 8A and 8B. Since the Blood Glucose Measurement (BGM) is 160mg/dl and the Bolus Trigger (BT) is 100mg/dl, the control circuit 14 proceeds to step 234 and calculates Δ BG-160 mg/dl-100 mg/dl-60 mg/dl, CB-1.5 i.u. (60mg/dl)/(40mg/dl/i.u.) and BGU-100 mg/dl +60 mg/dl-160 mg/dl. Also at step 234, control circuit 14 inputs the correction bolus time stamp (CBTS — T0) and the corresponding Δ BG 60mg/dl into the correction bolus stack to indicate that the first correction insulin bolus stop time period (LOT1) is now active with the corresponding Δ BG 60mg/dl as shown by shaded region 300. Since the previous meal activity flag (PMA) is "false" and the Carbohydrate Estimate (CE) is not greater than the TCI, execution of the correction bolus processing routine advances to step 226 where the control circuit 14 is operable to set BT at 160mg/dl at step 226. Thereafter, at step 242, execution of the routine returns to step 118 of the algorithm 100.

At step 120, the control circuit 14 executes the total insulin bolus processing routine of FIG. 9. Since the meal compensation insulin bolus (MB) is zero, the control circuit 14 is operable to set TB 1.5i.u. Thereafter, at step 256, execution of the routine returns to step 120 of the algorithm 100.

Since no alert is set, the algorithm 100 proceeds to step 134 where the display 88 (see, e.g., FIG. 4E) displays a total insulin bolus amount of 1.5I.U. at step 134. Without defining the adjustment level, the user accepts the initial result and the algorithm 100 proceeds to step 140 to display the final result, e.g., via the display 90 of FIG. 4F. The user accepts the total recommended insulin bolus amount of 1.5i.u., and execution of the algorithm 100 terminates after storing the current values of the parameter set. The recommended insulin bolus amount of 1.5i.u. is then dispensed to the user.

At time T1, the user again executes the algorithm 100 and inputs BGM at step 106₁160mg/dl and CE 0. Thereafter at step 112, a correction bolus stack processing routine is invoked. Since T0+120 minutes is no later than T1, the correction bolus stack entry is not processed for removal and execution of the routine returns to step 112 of algorithm 100. Steps 114 and 116 provide no new information and execution of the correction bolus processing routine of step 118 leads to step 236, at step 236, the control circuit 14 is operable to set CB-0 as BGM-BT and then to step 226, at step 226, the control circuit 14 is again operable to set BT-160 mg/dl. Since MB-CB-0, execution of the total insulin bolus processing routine of step 120 results in a total recommended insulin bolus amount of zero.

At time T2, the user again executes the algorithm 100 and inputs BGM at step 106₂190mg/dl and CE 0. Thereafter at step 112, a correction bolus stack processing routine is invoked. Since T0+120 minutes is no later than T2, the correction bolus stack entry is not processed for removal and execution of the routine returns to step 112 of algorithm 100. Steps 114 and 116 do not provideThe new information, and execution of the correction bolus processing routine of step 118 leads to step 234 where the control circuit 14 is operable to calculate Δ BG-190 mg/dl-160 mg/dl-30 mg/dl, CB-0.75 i.u. (30mg/dl)/(40mg/dl/i.u.), and BGU-160 mg/dl +30 mg/dl-190 mg/dl. Also at step 234, the control circuit 14 inputs the correction bolus time stamp (CBTS — T2) and the corresponding Δ BG of 30mg/dl into the correction bolus stack to indicate that the second correction insulin bolus stop time period (LOT2) is now valid with the corresponding Δ BG of 30mg/dl as shown by the shaded regions 302A and 302B. Execution of the correction bolus processing routine then proceeds to step 226 where the control circuit 14 is operable to set BT at 190mg/dl at step 226. Thereafter, at step 242, execution of the routine returns to step 118 of the algorithm 100.

At step 120, the control circuit 14 executes the total insulin bolus processing routine of FIG. 9. Since the meal compensation insulin bolus (MB) is zero, the control circuit 14 is operable to set TB 0.75i.u. Thereafter, at step 256, execution of the routine returns to step 120 of the algorithm 100.

Since no alert is set, the algorithm 100 proceeds to step 134 where the display 88 (see, e.g., FIG. 4E) displays a total insulin bolus amount of 0.75I.U. at step 134. Without defining the adjustment level, the user accepts the initial result and the algorithm 100 proceeds to step 140 to display the final result, for example, via the display 90 of FIG. 4F. The user accepts the total recommended insulin bolus amount of 0.75i.u., and execution of the algorithm 100 is terminated after storing the current values of the parameter set. The recommended insulin bolus amount of 0.75i.u. is then dispensed to the user. It should be appreciated that the control circuit 14 may be configured to round the total recommended insulin bolus amount to the nearest specified increment value. For example, control computer 14 may be configured to calculate the total insulin bolus amount as well as any corrected insulin bolus amount (CB) and/or meal compensation bolus amount (MB) as the nearest tenth of an i.u. In this example, the display 90 is thus configured to display 0.8i.u. or 0.7i.u. as the total insulin bolus amount, depending on whether the control circuit 14 is configured to drop only or not. As another example, the administration of a total insulin bolus may be accomplished via an insulin pump or other automatic dosing unit, and in this example, the amount administered may only be available in predetermined increments (e.g., increments of 0.2 i.u.). In this example, such an automatic dosing unit may then dose 0.8i.u. or 0.6i.u., depending on whether the control circuit 14 is configured to drop only or not. In any case, the control circuit 14 may be configured to require the user to manually accept or change the total recommended insulin bolus amount before being dispensed.

At a time between T3 and T4, the user again executes the algorithm 100 and inputs BGM at step 106₃160mg/dl and CE 0. Thereafter at step 112, a correction bolus stack processing routine is invoked. Since T0+120 minutes is no later than the current time (now between T3 and T4), the first correction bolus stack entry is not processed for removal, and since T2+120 minutes is no later than the current time, the second correction bolus stack entry is also not processed for removal. Execution of the routine then returns to step 112 of the algorithm 100. Steps 114 and 116 again provide no new information and execution of the correction bolus processing routine of step 118 leads to step 236, at step 236, with BGM < BT, the control circuit 14 is operable to set CB to 0, and then to step 226, at step 226, the control circuit 14 is again operable to set BT to 190 mg/dl. Since MB-CB-0, execution of the total insulin bolus processing routine of step 120 results in a total recommended insulin bolus amount of zero.

At time T5, the user again executes the algorithm 100 and inputs BGM at step 106₄160mg/dl and CE 0. Thereafter at step 112, the correction bolus stack processing routine of FIG. 5 is invoked. Since T0+120 minutes is later than T5, a correction bolus stack entry with CBTS-T0 corresponding to the correction insulin bolus stop time period (LOT1) is processed via steps 154 and 156 by: the corresponding Δ BG value associated with CBTS ═ T0 is subtracted from the current upper blood glucose limit target (BGU) (currently 190mg/dl)(60mg/dl) to get BGU 130mg/dl, and also subtract this Δ BG value from the current Bolus Trigger (BT) (currently 190mg/dl) to get BT 130mg/dl, and then use the correction bolus stack entry flag with CBTS T0 for deletion from the correction bolus stack. Since T2+120 minutes is no later than T5, the second correction bolus stack entry is not processed for removal. Thereafter, at step 160, the first correction bolus stack entry (i.e., the first correction bolus stack entry having CBTS ═ T0) is deleted from the correction bolus stack, such that only one correction bolus stack entry is now retained, i.e., the correction bolus stack entries having CBTS ═ T2 and Δ BG ═ 30mg/dl are retained. Thereafter, at step 162, execution of the routine returns to step 112 of the algorithm 100. Again, no new information is provided at steps 114 and 116 and execution of the correction bolus processing routine of step 118 leads to step 234 where the control circuit 14 is operable to calculate Δ BG-160 mg/dl-130 mg/dl-30 mg/dl, CB-0.75 i.u. (30mg/dl)/(40mg/dl/i.u.) and BGU-130 mg/dl +30 mg/dl-160mg/dl at step 234. Also at step 234, the control circuit 14 inputs the correction bolus time stamp (CBTS — T5) and the corresponding Δ BG of 30mg/dl into the correction bolus stack to indicate that the third correction insulin bolus stop time period (LOT3) is now active with the corresponding Δ BG of 60mg/dl as shown by shaded blocks 304A and 304B. Execution of the correction bolus processing routine then proceeds to step 226 where the control circuit 14 is operable to set BT at 160mg/dl at step 226. Thereafter, at step 242, execution of the routine returns to step 118 of the algorithm 100.

At step 120, the control circuit 14 executes the total insulin bolus processing routine of FIG. 9. Since the meal compensation insulin bolus (MB) is zero, the control circuit 14 is operable to set TB 0.75i.u. Thereafter, at step 256, execution of the routine is returned to step 120 of the algorithm 100.

Since no alert is set, the algorithm 100 proceeds to step 134 where the display 88 (see, e.g., FIG. 4E) displays a total insulin bolus amount of 0.75I.U. at step 134. Without defining the adjustment level, the user accepts the initial result and the algorithm 100 proceeds to step 140 to display the final result, for example, via the display 90 of FIG. 4F. The user accepts the total recommended insulin bolus amount of 0.75i.u., and execution of the algorithm 100 is terminated after storing the current values of the parameter set. The recommended insulin bolus amount of 0.75i.u. is then dispensed to the user near time T5.

At time T7, the user again executes the algorithm 100 and inputs BGM at step 106₅125mg/dl and CE 0. Thereafter at step 112, a correction bolus stack processing routine is invoked. Since T2+120 minutes is later than T7, the correction bolus stack entry with CBTS T2 is processed via steps 154 and 156 by: the corresponding Δ BG value (30mg/dl) associated with CBTS ═ T2 is subtracted from the current upper blood glucose limit target (BGU) (currently 160mg/dl) to get BGU ═ 130mg/dl, and this Δ BG value is also subtracted from the bolus trigger (currently 160mg/dl) to get BT ═ 130mg/dl, and then the correction stack entry with CBTS ═ T2 is marked as deleted from the correction bolus stack. Since T5+120 minutes is no later than T7, the remaining correction bolus stack entries are not processed for removal. Thereafter, at step 160, the correction bolus stack entry with CBTS ═ T2 is deleted from the correction bolus stack, such that only one correction bolus stack entry is now retained, i.e., the correction bolus stack entries with CBTS ═ T5 and Δ BG ═ 30mg/dl are retained. Thereafter, at step 162, execution of the routine returns to step 112 of the algorithm 100. Execution of the routine then returns to step 112 of the algorithm 100. Steps 114 and 116 again provide no new information and execution of the correction bolus processing routine of step 118 leads to step 236, at step 236, with BGM < BT, the control circuit 14 is operable to set CB to 0, and then to step 226, at step 226, the control circuit 14 is again operable to set BT to 130 mg/dl. Since MB-CB-0, execution of the total insulin bolus processing routine of step 120 results in a total recommended insulin bolus amount of zero.

Example 2

With the aid of fig. 11, another example of the operation of the algorithm 100 will now be provided. In this example, the meal will be ingested at or near time T1, and this example therefore includes the calculation and recommendation of a meal compensation insulin bolus amount. This example again assumes that the initialization or setup process shown in fig. 2A-2N and 2P-2Q has been performed previously, resulting in the calculation factors, general parameters and optional parameters available during the indicated deadlines in this example and shown in table 2 below:

TABLE 2

Referring now to fig. 11, a graph of blood glucose and correction-compensation bolus versus time illustrating this example is shown. With the setup complete, the algorithm 100 prompts the user to enter the current Blood Glucose Measurement (BGM) and Carbohydrate Estimate (CE) at step 106. At time T0, the user obtains a Blood Glucose Measurement (BGM)₀) And therefore 160mg/dl of BGM is input in the display 80. Since no meal will be ingested at T0 or near T0, the user also enters a CE of 0gr in the display 80. Thereafter, in step 108, control circuit 14 retrieves the parameter set corresponding to the information in table 2 from the database stored in storage unit 20. At step 110, control circuit 14 also retrieves the current value of the Bolus Trigger (BT), the upper glucose limit target (BGU), the Meal Bolus Timestamp (MBTS) and the previous meal activity flag (PMA), and the correction bolus stack. For the first execution of algorithm 100, BT — BGU — 100mg/dl, MBTS — 0, PMA is false, and the correction bolus stack is emptied.

At step 112, control circuit 14 executes the correction bolus stack processing routine of FIG. 5. Since the correction bolus stack is emptied, execution of the routine is returned to step 112 of algorithm 100. Thereafter, at step 114, the control circuit 14 executes the meal bolus time processing routine of FIG. 6. Since the Meal Bolus Time Stamp (MBTS) is zero (i.e., not "set"), step 170 of the meal bolus time processing routine proceeds directly to step 178, where execution of the routine returns to step 114 of algorithm 10O.

At step 118, the control circuit 14 executes the correction bolus processing routine of FIGS. 8A and 8B. Since the Blood Glucose Measurement (BGM) is 160mg/dl and the Bolus Trigger (BT) is 100mg/dl, the control circuit 14 proceeds to step 234 and calculates Δ BG-160 mg/dl-100 mg/dl-60 mg/dl, CB-1.5 i.u. (60mg/dl)/(40mg/dl/i.u.) and BGU-100 mg/dl +60 mg/dl-160 mg/dl. Also at step 234, the control circuit 14 inputs the correction bolus time stamp (CBTS — T0) and the corresponding Δ BG 60mg/dl into the correction bolus stack to indicate that the first correction insulin bolus stop time period (LOT1) is now active with the corresponding Δ BG 60mg/dl as shown by the shaded region 350. Since the previous meal activity flag (PMA) is "false" and the Carbohydrate Estimate (CE) is not greater than the TCI, execution of the correction bolus processing routine advances to step 226 where the control circuit 14 is operable to set BT at 160mg/dl at step 226. Thereafter, at step 242, execution of the routine returns to step 118 of the algorithm 100.

Since no alert is set, the algorithm 100 proceeds to step 134 where the display 88 (see, e.g., FIG. 4E) displays a total insulin bolus amount of 1.5I.U. at step 134. Without defining the adjustment level, the user accepts the initial result and the algorithm 100 proceeds to step 140 to display the final result, for example, via the display 90 of FIG. 4F. The user accepts the total recommended insulin bolus amount of 1.5i.u., and execution of the algorithm 100 is terminated after storing the current values of the parameter set. The recommended insulin bolus amount of 1.5i.u. is then dispensed to the user.

At time T1, the user againAlgorithm 100 is executed and BGM is input at step 106₁150 mg/dl. The user plans to immediately ingest a meal with approximately 12 grams of carbohydrates, and the user therefore also inputs CE-12 at step 160. Thereafter at step 112, a correction bolus stack processing routine is invoked. Since T0+120 minutes is no later than T1, the correction bolus stack entry is not processed for removal and execution of the routine returns to step 112 of algorithm 100. Thereafter, at step 114, the control circuit 14 executes the meal bolus time processing routine of FIG. 6. Since the Meal Bolus Time Stamp (MBTS) is zero (i.e., not "set"), step 170 of the meal bolus time processing routine proceeds directly to step 178, where execution of the routine returns to step 114 of algorithm 100.

At step 116, the control circuit 14 executes the meal compensation bolus processing routine of FIG. 7. Since the estimated carbohydrate amount (CE) entered by the user at step 106 is greater than zero, step 180 of the meal compensation bolus processing routine advances to step 182 where the control circuit 14 is operable to calculate a meal compensation insulin bolus amount (MB ═ (12gr.) (1.0i.u./10gr. carbohydrate) ═ 1.2i.u.) at step 182. Thereafter, since CE > TCI, the control circuit 14 is operable at step 186 to set the post-prandial blood glucose increase value Δ BGPP at 50mg/dl, and thereafter at step 188 to set the meal bolus time stamp MBTS at T1 to indicate that the post-prandial stop time period (TPP) is now active at the corresponding Δ BGPP at 50mg/dl as shown by shaded areas 352A and 352B. Thereafter, at step 192, execution of the routine returns to step 116 of the algorithm 100.

At step 118, the control circuit 14 executes the correction bolus processing routine of FIGS. 8A and 8B. Since the blood glucose measurement result (BGM) is 150mg/dl and BT is 160mg/dl, the control circuit 14 proceeds to step 236 and sets the correction insulin bolus amount CB to 0. Thereafter at step 238, since the previous meal activity flag (PMA) is "FALSE", execution of the correction insulin bolus processing routine proceeds to step 220. Since CE > TCI, the control circuit 14 is operable at step 222 to set the previous meal activity flag (PMA) to TRUE, and thereafter calculate a bolus trigger (BT-MAX (160mg/dl, 150mg/dl +50mg/dl) — 200mg/dl) at step 224. Thereafter, at step 242, execution of the routine returns to step 118 of the algorithm 100.

At step 120, the control circuit 14 executes the total insulin bolus processing routine of FIG. 9. Since the corrected insulin bolus (CB) is zero, the control circuit 14 is operable to set TB-MB-1.2 i.u. Thereafter, at step 256, execution of the routine returns to step 120 of the algorithm 100.

Since no alert is set, the algorithm 100 proceeds to step 134 where the display 88 (see, e.g., fig. 4E) displays a total insulin bolus amount of 1.2i.u. at step 134. Without defining the adjustment level, the user accepts the initial result and the algorithm 100 proceeds to step 140 to display the final result, for example, via the display 90 of FIG. 4F. The user accepts the total recommended insulin bolus amount of 1.2i.u., and execution of the algorithm 100 is terminated after storing the current values of the parameter set. The recommended insulin bolus amount of 1.2i.u. is then dispensed to the user.

At time T3, the user again executes the algorithm 100 and inputs BGM at step 106₂220mg/dl and CE 0. Thereafter at step 112, a correction bolus stack processing routine is invoked. Since T0+120 minutes is no later than T2, the correction bolus stack entry is not processed for removal and execution of the routine returns to step 112 of algorithm 100. At step 114, the control circuit executes the meal bolus time processing routine of FIG. 6. Since T1+150 minutes (TPP) is no later than T2, execution of the routine returns to step 114 of algorithm 100. At step 116 of algorithm 100, control circuit 14 executes the meal compensation bolus processing algorithm of FIG. 7. Since CE is now no greater than zero, the control circuit 14 is operable to set the meal compensation insulin bolus amount (MB) equal to zero. Thereafter, at step 192, execution of the routine returns to step 116 of the algorithm 100. At step 118 of algorithm 100, control circuit 14 is operable to execute the correction bolus processing routine of FIGS. 8A and 8B. Because BGM is BGM₂> BGH, so the control circuit 14 will alarmThe ring is set to the hyperglycemic alert text. Thereafter at step 232, due to BGM₂The routine proceeds to step 234 where the control circuit 14 is operable to calculate Δ BG 220mg/dl-200mg/dl 20mg/dl, CB (20mg/dl)/(40mg/dl/i.u.) -0.5 i.u., and BGU 160mg/dl +20mg/dl 180mg/dl at step 234. Also at step 234, control circuit 14 inputs the correction bolus time stamp (CBTS — T3) and corresponding Δ BG of 20mg/dl into the correction bolus stack to indicate that the second correction insulin bolus stop time period (LOT2) is now valid with the corresponding Δ BG of 20mg/dl as shown by shaded regions 354A, 354B, and 354C. Since the previous meal activity flag (PMA) is now "true", execution of the correction bolus processing routine then proceeds to step 240 where the control circuit 14 is operable to set BT 180mg/dl +50mg/dl 230mg/dl at step 240. Thereafter, at step 242, execution of the routine returns to step 118 of the algorithm 100.

At step 120, the control circuit 14 executes the total insulin bolus processing routine of FIG. 9. Since the meal compensation insulin bolus (MB) is zero, the control circuit 14 is operable to set TB-CB-0.5 i.u. Thereafter, at step 256, execution of the routine returns to step 120 of the algorithm 100.

Since the hyperglycemic alert is set, the algorithm 100 proceeds to step 124 where the display 86 (see, e.g., FIG. 4D) displays the hyperglycemic alert at step 124. The user confirms the alert at step 126 and a timestamp of such confirmation is saved in the memory unit 20 at step 128. Since the alert does not correspond to a hypoglycemic alarm, the algorithm 100 proceeds to step 134 where the display 88 (see, e.g., FIG. 4E) displays a total insulin bolus value of 0.5I.U. at step 134. Without defining the adjustment level, the user accepts the initial result and the algorithm 100 proceeds to step 140 to display the final result, for example, via the display 90 of FIG. 4F. The user accepts the total recommended insulin bolus amount of 0.5i.u., and execution of the algorithm 100 is terminated after storing the current values of the parameter set. The recommended insulin bolus amount of 0.5i.u. is then dispensed to the user.

At time T5, the user again executes the algorithm 100 and inputs BGM at step 106₃160mg/dl and CE 0. Thereafter at step 112, the correction bolus stack processing routine of FIG. 5 is invoked. Since T0+120 minutes is later than T5, a correction bolus stack entry with CBTS-T0 corresponding to the correction insulin bolus stop time period (LOT1) is processed via steps 154 and 156 by: the corresponding Δ BG value (60mg/dl) associated with CBTS ═ T0 is subtracted from the current upper blood glucose limit target (BGU) (currently 180mg/dl) to get BGU ═ 120mg/dl, and this Δ BG value is also subtracted from the bolus trigger (currently 220mg/dl) to get BT ═ 160mg/dl, and then the correction bolus stack entry with CBTS ═ T0 is flagged for deletion from the correction bolus stack. Since T3+120 minutes is no later than T5, the second correction bolus stack entry is not processed for removal. Thereafter, in step 160, the first correction bolus stack entry, i.e., the first correction bolus stack entry having CBTS ═ T0, is deleted from the correction bolus stack, such that only one correction bolus stack entry, i.e., the correction bolus stack entries having CBTS ═ T2 and Δ BG ═ 20mg/dl, is now retained. Thereafter, at step 162, execution of the routine returns to step 112 of the algorithm 100.

At step 114, the control circuit 14 executes the meal bolus time processing routine of FIG. 6. Since T1+150 minutes (TPP) is no later than T5, execution of the routine returns to step 114 of algorithm 100. At step 116 of algorithm 100, control circuit 14 executes the meal compensation bolus processing algorithm of FIG. 7. Since CE is not greater than zero, the control circuit 14 is operable to set the meal compensation insulin bolus amount (MB) equal to zero. Thereafter, at step 192, execution of the routine returns to step 116 of the algorithm 100. At step 118 of algorithm 100, control circuit 14 is operable to execute the correction bolus processing routine of FIGS. 8A and 8B. At step 232, due to BGM₃160mg/dl is not greater than BT 160mg/dl, so execution of the routine advances to step 236 where the control circuit 14 is operable to set the corrected insulin bolus amount (CB) equal to zero at step 236. Since the previous meal Activity Mark (PMA) is still "true"Execution of the correction bolus processing routine then proceeds to step 240 where the control circuit 14 is operable to set BT at 120mg/dl +50mg/dl at 170mg/dl at step 240. Thereafter, at step 242, execution of the routine returns to step 118 of the algorithm 100.

At step 120, the control circuit 14 executes the total insulin bolus processing routine of FIG. 9. Since the meal compensation insulin bolus amount (MB) is zero and the corrected insulin bolus amount (CB) is zero, the control circuit 14 is operable to set TB 0. Since MB-CB-0, execution of the total insulin bolus processing routine of step 120 results in a total recommended insulin bolus amount of zero.

At a time between T6 and T7, the user again executes the algorithm 100 and inputs BGM at step 106₄120mg/dl and CE 0. Thereafter at step 112, the correction bolus stack processing routine of FIG. 5 is invoked. Since T3+120 minutes is no later than the current time, the correction bolus stack entry corresponding to CBTS ═ T3 is not processed for removal. Thereafter, at step 162, execution of the routine returns to step 112 of the algorithm 100.

At step 114, the control circuit 14 executes the meal bolus time processing routine of FIG. 6. Since T1+150 minutes (TPP) is later than the current time, the post-prandial stop time period (TPP) has expired, and the control circuit 14 subtracts the post-prandial blood glucose increase value (Δ BGPP) from the current value of the Bolus Trigger (BT) (currently 170mg/dl) to get BT-120 mg/dl at step 172, and thereafter sets the post-prandial blood glucose increase value (Δ BGPP) equal to zero at step 174. At step 176, the control circuit 14 sets the previous meal activity flag (PMA) to false and clears the Meal Bolus Timestamp (MBTS). Thereafter, at step 178, execution of the routine returns to step 114 of the algorithm 100. At step 116 of algorithm 100, control circuit 14 executes the meal compensation bolus processing algorithm of FIG. 7. Since CE is not greater than zero, the control circuit 14 is operable to set the meal compensation insulin bolus amount (MB) equal to zero. Thereafter, at step 192, execution of the routine returns to step 116 of the algorithm 100. In step 118 of the algorithm 100, controlCircuitry 14 is operable to execute the correction bolus processing routine of fig. 8A and 8B. At step 232, due to BGM₄120mg/dl is not greater than BT 170mg/dl, execution of the routine advances to step 236 where the control circuit 14 is operable to set the corrected insulin bolus amount (CB) equal to zero at step 236. Since the previous meal activity flag (PMA) is now "false", execution of the correction bolus processing routine then proceeds to step 226 where the control circuit 14 is operable to set BT — BGU — 120mg/dl at step 226. Thereafter, at step 242, execution of the routine returns to step 118 of the algorithm 100.

While the invention has been illustrated and described in detail 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.

Claims

1. A method for recommending an insulin bolus amount to a user, the method comprising the steps of:

a blood glucose target is established for the user,

the current blood glucose value of the user is received,

if the current blood glucose value exceeds the blood glucose target, determining a recommended insulin bolus amount,

calculating the difference as the current blood glucose value minus the blood glucose target, an

If the difference is positive, the blood glucose target is increased by the difference for the rest time period.

2. The method of claim 1, further comprising the step of repeating the receiving, determining, calculating, and adding steps.

3. The method of claim 1 or 2, wherein the determining step comprises calculating the recommended insulin bolus amount as a ratio of a blood glucose increase value and an insulin sensitivity value.

4. The method according to claims 1-3, further comprising the step of generating a hyperglycemic alert if the current blood glucose value is greater than the hyperglycemic alert value.

5. A method according to claims 1-4, further comprising the step of generating a hypoglycemic alert if the current blood glucose value is less than the hypoglycemic alert value.

6. The method of claims 1-5, further comprising the step of generating a hypoglycemic alarm alert if the current blood glucose value is less than the hypoglycemic alarm value.

7. A method for recommending insulin bolus quantities to an insulin user, the method comprising the steps of:

an initial blood glucose target is established for the user,

a current blood glucose value of the user is received at a first time,

if the current blood glucose value obtained at the first time exceeds the initial blood glucose target, a first recommended insulin bolus amount is determined,

the first difference is calculated as the user's current blood glucose value at the first time minus the initial blood glucose target,

if the first difference is positive, calculating the first modified glycemic target as a sum of the initial glycemic target and the first difference,

after the first time and after the first recommended insulin bolus amount is dispensed to the user, but before expiration of the first stop time period since the first time, receiving a current blood glucose value from the user at a second time, an

A second recommended insulin bolus amount is determined for the user if the current blood glucose value at the second time exceeds the first modified blood glucose target.

8. The method of claim 7, further comprising the steps of:

calculating a second difference as the user's current blood glucose value at a second time minus the first modified blood glucose target, an

If the second difference is positive, the second modified glycemic target is calculated as the sum of the first modified glycemic target and the second difference.

9. The method of claim 8, further comprising the steps of:

receiving a current blood glucose value from the user at a third time after the second time and after the second recommended insulin bolus amount is dispensed to the user, but before expiration of the first stop time period since the first time and before expiration of the second stop time period since the second time, and

determining a third recommended insulin bolus amount for the user if the current blood glucose value at the third time exceeds the second modified blood glucose target.

10. The method of claim 9, further comprising the steps of:

calculating a third difference as the user's current blood glucose value at a third time instant minus the second modified blood glucose target, an

If the third difference is positive, the third modified glycemic target is calculated as the sum of the second modified glycemic target and the third difference.

11. The method according to claims 8-10, further comprising the steps of:

after the second time instant, after the second recommended insulin bolus amount is dispensed to the user, and after expiration of the first stop time period since the first time instant, but before expiration of the second stop time period since the second time instant, receiving a current blood glucose value from the user at a third time instant,

calculating a third modified glycemic target as the second modified glycemic target minus the first difference, an

Determining a third recommended insulin bolus amount for the user if the current blood glucose value at the third time exceeds the third modified blood glucose target.

12. The method of claim 11, further comprising the steps of:

calculating a third difference as the current blood glucose value at the third time instant minus the third modified blood glucose target, an

If the third difference is positive, the fourth modified glycemic target is calculated as the sum of the third modified glycemic target and the third difference.

13. A method according to claims 7-12, further comprising the step of generating a hyperglycemic alert if the current blood glucose value received at any one of the first and second times is greater than the hyperglycemic alert value.

14. A method according to claims 7-13, further comprising the step of generating a hypoglycemic alert if the current blood glucose value received at any one of the first and second times is less than the hypoglycemic alert value.

15. The method of claims 7-14, further comprising the step of generating a hypoglycemic alarm alert if the current blood glucose value received at any one of the first and second times is less than the hypoglycemic alarm value.

16. A system for recommending insulin bolus quantities to an insulin user, the system comprising:

a data input device for providing information from a user.

A display for displaying information to a user, an

A control circuit including a memory having a user blood glucose target stored therein, the control circuit receiving a current blood glucose value of the user from information provided by the user via the data input device, the control circuit determining a recommended insulin bolus amount if the current blood glucose value exceeds the blood glucose target, calculating a difference as the current blood glucose value minus the blood glucose target, and if the difference is positive, increasing the blood glucose target by the difference at a rest time period, the control circuit controlling the display to display the recommended insulin bolus amount to the user.

17. The system of claim 16, wherein the control circuitry is configured to repeatedly receive a current blood glucose value of the user from information provided by the user via the data input device, determine a recommended insulin bolus amount if the current blood glucose value exceeds a blood glucose target, calculate a difference as the current blood glucose value minus the blood glucose target, increase the blood glucose target by the difference for a rest time period if the difference is positive, and control the display to display the recommended insulin bolus amount to the user.

18. The system according to claim 16 or 17, wherein the control circuitry is configured to control the display to display a hyperglycemic alert if the current blood glucose value is greater than the hyperglycemic alert value.

19. The system according to claims 16-18, wherein the control circuitry is configured to control the display to display a hypoglycemic alert if the current blood glucose value is less than the hypoglycemic alert value.

20. The system of claims 16-18, wherein the control circuitry is configured to control the display to display a low blood glucose alarm if the current blood glucose value is less than the low blood glucose alarm value.

21. A method for recommending insulin bolus quantities to an insulin user, the method comprising the steps of:

a blood glucose target is established for the user,

receiving a carbohydrate value representing an amount of carbohydrate to be subsequently ingested by a user,

determining a recommended compensated insulin bolus based on the carbohydrate value, an

If the carbohydrate value exceeds the threshold value, the glycemic target is increased by a post-prandial increment value to produce a first modified glycemic target at a post-prandial rest time period.

22. The method of claim 21, further comprising the steps of:

after dispensing the recommended bolus of compensated insulin to the user, but before expiration of the post-prandial rest time period, receiving a first current blood glucose value of the user,

if the first current blood glucose value exceeds the first modified blood glucose target, determining a first recommended corrected insulin bolus amount,

calculating a first difference as the first current blood glucose value minus the first modified blood glucose target, an

If the first difference is positive, the modified glycemic target is increased by the first difference to produce a second modified glycemic target at the first corrected stop time period.

23. The method of claim 22, further comprising the steps of:

after dispensing the recommended compensation insulin bolus to the user, after dispensing the first recommended correction insulin bolus to the user, and after expiration of the post-prandial rest time period, but before expiration of the first correction rest time period, receiving a second current blood glucose value of the user,

reducing the second modified glycemic target by the postprandial increase value to produce a third modified glycemic target,

if the second current blood glucose value exceeds the third modified blood glucose target, determining a second recommended corrected insulin bolus amount,

calculating a second difference as the second current blood glucose value minus the third modified blood glucose target, an

If the second difference is positive, the third modified blood glucose target is increased by the second difference to produce a fourth modified blood glucose target at a second correction stop time period.

24. The method according to claim 23, further comprising the step of generating a hyperglycemic alert if any of the first, second and third current blood glucose values is greater than the hyperglycemic alert value.

25. The method according to claim 23 or 24, further comprising the step of generating a hypoglycemic alert if any of the first, second and third current blood glucose values is less than the hypoglycemic alert value.

26. The method of claims 23-25, further comprising the step of generating a hypoglycemic alarm alert if any of the first, second and third blood glucose values is less than the hypoglycemic alarm value.

27. A system for recommending insulin bolus quantities to an insulin user, the system comprising:

a data input device for providing information from a user,

a display for displaying information to a user, an

A control circuit including a memory having a user blood glucose target stored therein, the control circuit receiving a carbohydrate value from information provided by the user via the data input device, the carbohydrate value representing an amount of carbohydrate to be subsequently ingested by the user, the control circuit determining a recommended compensated insulin bolus amount from the carbohydrate value and increasing the blood glucose target by a postprandial increase value if the carbohydrate value exceeds a threshold value to produce a first modified blood glucose target at a postprandial rest time period, the control circuit controlling the display to display the recommended compensated insulin bolus amount to the user.

28. The system of claim 27, wherein after the recommended compensated insulin bolus is dispensed to the user, the control circuitry receives a current blood glucose value of the user from information provided by the user via the data input device, determines a recommended correction insulin bolus amount if the current blood glucose value exceeds a first modified blood glucose target, calculates a difference as the current blood glucose value minus the first modified blood glucose target, and increases the first modified blood glucose target by the difference if the difference is positive to produce a second modified blood glucose target at a correction rest time period, the control circuitry controlling the display to display the recommended correction insulin bolus amount to the user.

29. The system according to claim 27 or 28, wherein the control circuitry is configured to control the display to display a hyperglycemic alert if the current blood glucose value is greater than a hyperglycemic alert value.

30. The system according to claims 27-29, wherein the control circuitry is configured to control the display to display a hypoglycemic alert if the current blood glucose value is less than the hypoglycemic alert value.

31. The system of claims 27-30, wherein the control circuitry is configured to control the display to display a low blood glucose alarm if the current blood glucose value is less than the low blood glucose alarm value.

32. A method for recommending insulin bolus quantities to an insulin user, the method comprising the steps of:

a blood glucose target is established for the user,

receiving a first current blood glucose value of the user and a carbohydrate value representing an amount of carbohydrate to be subsequently ingested by the user,

determining a recommended compensated insulin bolus based on the carbohydrate value,

if the first current blood glucose value exceeds the blood glucose target, determining a first recommended corrected insulin bolus amount,

if the carbohydrate value exceeds the threshold value, increasing the glycemic target by a postprandial increase value for a postprandial rest time period, an

If the first difference is positive, increasing the blood glucose target by a first difference during a first correction stop time period, the first difference being calculated as the first current blood glucose value minus the blood glucose target,

wherein the blood glucose target increased by any one of the post-prandial increase value and the first difference value corresponds to the first modified blood glucose target.

33. The method of claim 32, further comprising the steps of:

receiving a second current blood glucose value of the user after the recommended compensated insulin bolus amount and the recommended first corrected insulin bolus amount are dispensed to the user, but before the expiration of the post-prandial rest time period and before the expiration of the first corrected rest time period,

determining a second recommended corrected insulin bolus amount if the second current blood glucose value exceeds the blood glucose target, an

Calculating a second difference as the second current blood glucose value minus the first modified blood glucose target, an

If the second difference is positive, the first modified blood glucose target is increased by the second difference to produce a second modified blood glucose target at a second correction stop time period.

34. The method according to claim 32 or 33, further comprising the step of:

after the recommended compensated insulin bolus amount and the recommended first corrected insulin bolus amount are dispensed to the user, and after expiration of the post-prandial rest time period, but before expiration of the first corrected rest time period, receiving a second current blood glucose value of the user,

reducing the first modified glycemic target by the postprandial increase value to produce a second modified glycemic target,

determining a second recommended corrected insulin bolus amount if the second current blood glucose value exceeds the second modified blood glucose target, an

Calculating a second difference as a second current blood glucose value minus a second modified blood glucose target, an

If the second difference is positive, the second modified blood glucose target is increased by the second difference to produce a third modified blood glucose target at a second correction stop time period.

35. The method according to claim 34, further comprising the step of generating a hyperglycemic alert if either of the first and second current blood glucose values is greater than the hyperglycemic alert value.

36. The method according to claim 34, further comprising the step of generating a hypoglycemic alert if either of the first and second current blood glucose values is less than the hypoglycemic alert value.

37. The method of claim 34, further comprising the step of generating a hypoglycemic alarm alert if either of the first and second current blood glucose values is less than the hypoglycemic alarm value.

38. A system for recommending insulin bolus quantities to an insulin user, the system comprising:

a data input device for providing information from a user,

a display for displaying information to a user, an

A control circuit including a memory having a user's blood glucose target stored therein, the control circuit receives the current user blood glucose and carbohydrate values from information provided by the user via the data input device, the carbohydrate value represents an amount of carbohydrates that will be subsequently ingested by the user by establishing a blood glucose target for the user, the control circuit determines a recommended compensated insulin bolus amount based on the carbohydrate value and determines a recommended corrected insulin bolus amount if the current blood glucose value exceeds the blood glucose target, if the carbohydrate value exceeds the threshold value, the control circuit increases the blood glucose target by a post-prandial increase value for a post-prandial rest time period, and if the difference is positive, increasing the blood glucose target by a difference corresponding to the current blood glucose value minus the blood glucose target for a correction stop time period, the control circuit controls the display to display the recommended compensation and correction insulin bolus amount to the user.

39. The system according to claim 38, wherein the control circuitry is configured to control the display to display a hyperglycemic alert if the current blood glucose value is greater than the hyperglycemic alert value.

40. The system according to claim 38 or 39, wherein the control circuitry is configured to control the display to display a hypoglycemic alert if the current blood glucose value is less than the hypoglycemic alert value.

41. The system of claims 38-40, wherein the control circuitry is configured to control the display to display a low blood glucose alarm if the current blood glucose value is less than the low blood glucose alarm value.