1. A system for detecting analyte levels in at least one person of interest, comprising;
an introducer; and
an analyte sensor coupled to the introducer for positioning at least a portion of the analyte sensor transcutaneously, the analyte sensor configured to require no calibration after positioning in the at least one person of interest by the introducer.
Analyte monitoring system and methods
Blood glucose tracking apparatus
Glucose measuring device for use in personal area network
Method and system for providing basal profile modification in analyte monitoring and management systems
INTEGRATED INTRA-DERMAL DELIVERY, DIAGNOSTIC AND COMMUNICATION SYSTEM
New World Pharmaceuticals LLC
Method and system for powering an electronic device
Method and apparatus for providing rolling data in communication systems
Method and apparatus for providing leak detection in data monitoring and management systems
Analyte monitoring devices and methods therefor
Blood glucose tracking apparatus and methods
Method for automatically and rapidly distinguishing between control and sample solutions in a biosensor strip
Method and device for determining elapsed sensor life
Method and system for providing contextual based medication dosage determination
Method and system for providing data communication in continuous glucose monitoring and management system
Analyte monitoring system and methods for managing power and noise
Error detection in critical repeating data in a wireless sensor system
Analyte signal processing device and methods
Methods and apparatuses for providing adverse condition notification with enhanced wireless communication range in analyte monitoring systems
Analyte monitoring device and methods
Home hub for reporting patient health parameters
Agilent Technologies Incorporated
Method of manufacturing and testing an electronic device, and an electronic device
Round Rock Research LLC
Micron Technology Inc.
Device and method for sampling of substances using alternating polarity
Small volume in vitro analyte sensor with diffusible or non-leachable redox mediator
Microelectrogravimetric method for plating a biosensor
Remote psychological diagnosis and monitoring system
Handheld personal data assistant (PDA) with a medical device and method of using the same
ELECTRONICS METHODS FOR THE DETECTION OF ANALYTES
Osmetech Technology Inc.
Collection assemblies, laminates, and autosensor assemblies for use in transdermal sampling systems
Tissue electroperforation for enhanced drug delivery and diagnostic sampling
Johnson Johnson Consumer Companies Incorporated
Remote health monitoring and maintenance system
Methods of use for sensor based fluid detection devices
California Institute of Techn
Phonopneumograph system
Isonea Limited
Karmel Medical Acoustic Technologies Ltd.
Method and device for transdermal electrotransport delivery of fentanyl and sufentanil
ALZA Corporation
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System and method for stabilizing and removing tissue
Varian Medical Systems Incorporated
D. KRAG LLC
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Medtronic Incorporated
deltaDOT Limited
Imperial College of Science Technology Medicine
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Greatbatch Limited
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Implantable medical device microstrip telemetry antenna
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Body Science LLC
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Methods and apparatus for sampling body fluid
Roche Diabetes Care Inc.
Mercury Diagnostics Inc.
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Intermedics Incorporated
Sulzer Intermedics Inc.
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Motorola Inc.
Electrochemical sensors membrane
Electrocatalytic glucose sensor
Method and apparatus for determining glucose concentration in a biological sample
Boehringer Mannheim GmbH
Disposable glucose test strips, and methods and compositions for making same
LifeScan Scotland Limited
Selfcare Inc.
Syringe having electrical contact points for metering doses
RAYA Systems Incorporated
Computerized medical advice system and method including meta function
Clinical Decision Support LLC
First Opinion Corporation
Sensor device covered with foam membrane
Applied Medical Research
Portable biochemical measurement device using an enzyme sensor
Capacitance probe for fluid flow and volume measurements
US Government As Represented By The Director National Security Agency
United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration
Automated and interactive behavioral and medical guidance system
National Medical Research Council
William L. Bro
Tissue implant systems and methods for sustaining viable high cell densities within a host
Baxter International Inc.
Zero power receive detector for serial data interface
Boehringer Mannheim Corporation
Breathable liquid elimination analysis
Temple University of The Commonwealth System of Higher Education
Flex circuit connector
MINI Med Incorporated
Electronic animal identification system
Michael M. Kilroy, Rodney A. Stafford
Mechanical connector for securing compatible medical instruments together
Physio-Control Incorporated
Replaceable catheter system for physiological sensors, tissue stimulating electrodes and/or implantable fluid delivery systems
Alfred E. Mann Foundation For Scientific Research
Biosensor and method of quantitative analysis using the same
Kyoto Daiichi Kagaku Company Limited
Sensor for measuring the amount of a component in solution
Asulab SA
Biocompatible microcapsules
Board of Regents of the University of Texas System
Micro-electrode and method for preparing it
Mitsubishi Pencil Kabushiki Kaisha, Agency for Industrial Science and Technology
Signal processing method and apparatus
Bionir Inc.
Edward W. Stark
Biosensor with a data memory
Display device for indicating the internal pressure of the tube of an infusion pump
BAXTER INTERNATIONAL INC. ONE BAXTER PARKWAY DEERFIELD IL, Sharp Kabushiki Kaisha 22-22 Nagaike-Cho Abeno-Ku Osaka-Shi Osaka-Fu
Sharp Electronics Corporation, Baxter International Inc.
Sealing device and method for inhibition of flow in capillary measuring devices
SOLARCARE TECHNOLOGIES CORPORATION A DE CORP.
Enzymatics Incorporated
Medical diagnostic system
Cascade Medical Inc.
Method and apparatus for diagnosis of sleep disorders
MAP MEDIZINTECHNIK FUR ARZT UND PATIENT GMBH
MADAUS SCHWARZER MEDIZINTECHNIK GMBH CO. KG
Carbon micro-sensor electrode and method for preparing it
Agency for Industrial Science and Technology
Apparatus for recording reagent test strip data by comparison to color lights on a reference panel
Matria Healthcare Incorporated
Healthdyne Inc.
Wearable artificial pancreas
MENARINI INDUSTRIE FARMACEUTICHE S.R.L.
AMPLISCIENTIFICA S.R.L.
Medication infusion pump with improved liquid-vapor pressure reservoir
MINIMED TECHNOLOGIES LTD.
Subcutaneous injection set with improved cannula mounting arrangement
Polarographic chemical sensor with external reference electrode
Mallinckrodt Sensor Systems Inc.
Interactive medication delivery system
Healthtech Services Corporation
HEALTHTECH SERVICES CORP.
Glucose sensor with gel-immobilized glucose oxidase and gluconolactonase
Enzyme electrochemical sensor electrode and method of making it
The United States of America As Represented By The Secretary of Agriculture
United States Of America As Represented By The Department Of Energy
Vivo refillable glucose sensor
Fitting for fastening the rail member of a drawer
Julius BLUM GmbH
Three-parameter optical fiber sensor and system
Luxtron Corp.
Continuous glucose monitoring and a system utilized therefor
NORTH-STAR RESEARCH INSTITUTE LTD. A CORP. OF DE
NORTHSTAR RESEARCH INSTITUTE LTD.
Two-dimensional diffusion glucose substrate sensing electrode
Pulse voltammetry
Cleveland Clinic Foundation
Novel fluorine-containing cyclic polymer
AGC Flat Glass Company Limited
Biosensor and method for making the same
Matsushita Electric Industrial Company Limited 1006 OAZA Kadoma-Shi Osaka Japan
Matsushita Electric Industrial Company Limited
Enzyme electrode
Omron Healthcare Company Limited
Omron Tateisi Electronics Co.
Moisture detection system for carpet cleaning apparatus
Dale G. Aycox, Kenneth Aycox
Electrochemical sensor having three layer membrane containing immobilized enzymes
Hitachi Ltd.
Hitachi America Limited
Methods and apparatus for monitoring cardiac output
LAWRENCE MEDICAL SYSTEMS INC. A CORP OF WASHINGTON
LAWRENCE MEDICAL SYSTEMS INC.
Microelectrochemical devices
Pressure regulated implantable infusion pump
Molecule-based microelectronic devices
Glucose medical monitoring system
Judson M. Dayton, Arthur R. Kudd
GARID INC.
Ambulatory ventricular function monitor
GENERAL HOSPITAL CORPORATION THE BOSTON MA A CORP. OF
The General Hospital Corporation
Device for the automatic insulin or glucose infusion in diabetic subjects, based on the continuous monitoring of the patient's glucose, obtained without blood withdrawal
Guiseppe Bombardieri
High glucose-determining analytical element
MILES LABORATORIES INC. ELKHART IND. A CORP. OF DE.
Miles Laboratories Inc.
Annular flow entrainment nebulizer
Viridian Inc.
VIRIDAN INC.
Apparatus and method for measurement and control of blood pressure
Purdue Research Foundation
Test means and method for interference resistant determination of oxidizing substances
Artificial beta cell
Hospital For SICK Children
ABB ROBOTICS INC.
Cincinnati Machines Incorporated
Multiple source battery-powered apparatus
Bell Howell LLC
Rate sensing batch analysis method
Beckman Instruments Inc.
AQUEOUS PROCESS FOR MAKING IMPROVED TETRAFLUOROETHYLENE / FLUOROALKYL PERFLUOROVINYL ETHER COPOLYMERS
E. I. du Pont de Nemours and Company
Gresham William Franklin, Vogelpohl Alfons Franz
View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17)
2. The system of claim 1 further including an output unit to output information related to a signal from the analyte sensor.
3. The system of claim 1 wherein the analyte sensor is factory calibrated.
4. The system of claim 1 wherein the introducer is configured to position the at least the portion of the analyte sensor in the at least one person of interest at a predetermined angle relative to a skin surface of the at least one person.
5. The system of claim 4 wherein the predetermined angle is no greater than approximately 90 degrees.
6. The system of claim 5 wherein the predetermined angle is less than approximately 90 degrees.
7. The system of claim 5 wherein the predetermined angle is no greater than approximately 45 degrees
9. The system of claim 5 wherein the predetermined angle is one of approximately 45 degrees or 90 degrees.
10. The system of claim 1 further including a transmitter configured to receive one or more signals from the analyte sensor.
11. The system of claim 10 wherein the one or more signals are associated with the analyte level.
12. The system of claim 10 further including a data processor configured to receive data from the transmitter.
13. The system of claim 12 wherein the data processor receives data from the transmitter wirelessly.
14. The system of claim 12 wherein the data processor is configured to output one or more indications based on the received data.
15. The system of claim 14 wherein the output indication is displayed visually, audibly, vibratorily, or any combinations thereof.
16. The system of claim 12 further including a drug administration system in communication with the data processor.
17. The system of claim 16 wherein the drug administration system is an internal or external infusion pump, a syringe injector, a transdermal delivery system, or an inhalation system.
18. A system for detecting analyte, comprising;
an analyte sensor at least a portion of which is positionable transcutaneously in a person of interest, the analyte sensor configured to require no calibration upon positioning by the introducer; and
an infusion device configured to receive one or more signals associated with the analyte level detected by the analyte sensor.
View Dependent Claims (19, 20)
19. The system of claim 18 wherein the infusion device is one of an external infusion device, an internal infusion device, or a syringe.
20. The system of claim 18 wherein the analyte sensor includes a glucose-responsive enzyme.
This application is a continuation of pending application Ser. No. 10/420,057 filed Apr. 18, 2003 which is a continuation of application Ser. No. 09/667,199 filed Sep. 21, 2000, now U.S. Pat. No. 6,565,509 B1, which is a continuation of application Ser. No. 09/070,677 filed Apr. 30, 1998 now U.S. Pat. No. 6,175,752 B1, the disclosure of each of which are incorporated herein by reference for all purposes, and each of which are assigned to assignee, Abbott Diabetes Care, Inc., of Alameda, Calif.
The monitoring of the level of glucose of other analytes, such as lactate or oxygen, in certain individuals is vitally important to their health. High or low levels of glucose or other analytes may be have detrimental effects. The monitoring of glucose is particularly important to individuals with diabetes, as they must determine when insulin is needed to reduce glucose levels in their bodies or when additional glucose is needed to raise the level of glucose in their bodies.
A "non-leachable" or "non-releasable" compound or a compound that is "non-Teachably disposed" is meant to define a compound that is affixed on the sensor such that it does not substantially diffuse away from the working surface of the working electrode for the period in which the sensor is used (e.g., the period in which the sensor is implanted in a patient or measuring a sample).
In one embodiment, the conductive material 56 is a part of a precursor material, such as a conductive ink, obtainable, for example, from Ercon, Inc. (Wareham, Mass.), Metech, Inc. (Elverson, Pa.), E.I. du Pont de Nemours and Co. (Wilmington, Del.), Emca-Remex Products (Montgomeryville, Pa.), or MCA Services (Melboum, Great Britain). The conductive ink is typically applied as a semiliquid or paste which contains particles of the carbon, metal, alloy, or metallic compound and a solvent or dispersant. After application of the conductive ink on the substrate 50 (e.g., in the channels 54), the solvent or dispersant evaporates to leave behind a solid mass of conductive material 56.
Conductive traces 52 (and channels 54, if used) can be formed with relatively narrow widths, for example, in the range of 25 to 250 μm, and including widths of, for example, 250 μm, 150 μm, 100 μm, 75 μm, 50 μm, 25 cm or less by the methods described above. In embodiments with two or more conductive traces 52 on the same side of the substrate 50, the conductive traces 52 are separated by distances sufficient to prevent conduction between the conductive traces 52. The edge-to-edge distance between the conductive traces is preferably in the range of 25 to 250 μm and may be, for example, 150 μm, 100 μm, 75 μm, 50 μm, or less. The density of the conductive traces 52 on the substrate 50 is preferably in the range of about 150 to 700 μm/trace and may be as small as 667 μm/trace or less, 333 μm/trace or less, or even 167 μm/trace or less.
The sensing layer 64 may be formed as a solid composition of the desired components (e.g., an electron transfer agent and/or a catalyst). These components are preferably non-leachable from the sensor 42 and more preferably are immobilized on the sensor 42. For example, the components may be immobilized on a working electrode 58. Alternatively, the components of the sensing layer 64 may be immobilized within or between one or more membranes or films disposed over the working electrode 58 or the components may be immobilized in a polymeric or sol-gel matrix. Examples of immobilized sensing layers are described in U.S. Pat. Nos. 5,262,035, 5.264,104, 5,264,105, 5,320,725, 5,593,852, and 5,665,222, U.S. patent application Ser. No. 08/540,789, and PCT Patent Application No. US98/02403 entitled "Soybean Peroxidase Electrochemical Sensor", filed on Feb. 11, 1998, Attorney Docket No. M&G 12008.8WO12, incorporated herein by reference.
In some embodiments, one or more of the components of the sensing layer 64 may be solvated, dispersed, or suspended in a fluid within the sensing layer 64, instead of forming a solid composition. The fluid may be provided with the sensor 42 or may be absorbed by the sensor 42 from the analyte-containing fluid. Preferably, the components which are solvated, dispersed, or suspended in this type of sensing layer 64 are non-leachable from the sensing layer. Non-leachability may be accomplished, for example, by providing barriers (e.g., the electrode, substrate, membranes, and/or films) around the sensing layer which prevent the leaching of the components of the sensing layer 64. One example of such a barrier is a microporous membrane or film which allows diffision of the analyte into the sensing layer 64 to make contact with the components of the sensing layer 64, but reduces or eliminates the diffusion of the sensing layer components (e.g., a electron transfer agent and/or a catalyst) out of the sensing layer 64.
For example, a glucose or lactate sensor may include a first sensing layer 64 which is spaced apart from the working electrode and contains an enzyme, for example, glucose oxidase or lactate oxidase. The reaction of glucose or lactate in the presence of the appropriate enzyme forms hydrogen peroxide. A second sensing layer 63 is provided directly on the working electrode 58a and contains a peroxidase enzyme and an electron transfer agent to generate a signal at the electrode in response to the hydrogen peroxide. The level of hydrogen peroxide indicated by the sensor then correlates to the level of glucose or lactate. Another sensor which operates similarly can be made using a single sensing layer with both the glucose or lactate oxidase and the peroxidase being deposited in the single sensing layer. Examples of such sensors are described in U.S. Pat. No. 5,593,852, U.S. patent application Ser. No. 08/540,789, and PCT Patent Application No. US98/02403 entitled "Soybean Peroxidase Electrochemical Sensor", filed on Feb. 11, 1998, Attorney Docket No. M&G 12008.8WO12, incorporated herein by reference.
Another consideration for in vivo analyte sensors is the thermostability of the catalyst. Many enzymes have only limited stability at biological temperatures. Thus, it may be necessary to use large amounts of the catalyst and/or use a catalyst that is thermostable at the necessary temperature (e.g., 37° C. or higher for normal body temperature). A thermostable catalyst may be defined as a catalyst which loses less than 5% of its activity when held at 37° C. for at least one hour, preferably, at least one day, and more preferably at least three days. One example of a thermostable catalyst is soybean peroxidase. This particular thermostable catalyst may be used in a glucose or lactate sensor when combined either in the same or separate sensing layers with glucose or lactate oxidase or dehydrogenase. A further description of thermostable catalysts and their use in electrochemical inventions is found in U.S. Pat. No. 5,665,222 U.S. patent application Ser. No. 08/540,789, and PCT Application No. US98/02403 entitled "Soybean Peroxidase Electrochemical Sensor", filed on Feb. 11, 1998, Attorney
When a potential is applied between the working electrode 58 and the counter electrode 60, an electrical current will flow. The current is a result of the electrolysis of the analyte or a second compound whose level is affected by the analyte. In one embodiment, the electrochemical reaction occurs via an electron transfer agent and the optional catalyst. Many analytes B are oxidized (or reduced) to products C by an electron transfer agent species A in the presence of an appropriate catalyst (e.g., an enzyme). The electron transfer agent A is then oxidized (or reduced) at the electrode. Electrons are collected by (or removed from) the electrode and the resulting current is measured. This process is illustrated by reaction equations (1) and (2) (similar equations may be written for the reduction of the analyte B by a redox mediator A in the presence of a catalyst): n⁢ ⁢A⁡(ox)+B⁢⟶catalyst⁢n⁢ ⁢A⁡(red)+C(1)n⁢ ⁢A⁡(red)⁢⟶electrode⁢n⁢ ⁢A⁡(ox)+n⁢ ⁢e-(2)
In another embodiment, a second compound whose level is affected by the analyte is electrolyzed at the working electrode. In some cases, the analyte D and the second compound, in this case, a reactant compound E, such as oxygen, react in the presence of the catalyst, as shown in reaction equation (3). D+E⁢⟶catalyst⁢F+G(3)
The reactant compound E is then directly oxidized (or reduced) at the working electrode, as shown in reaction equation (4) n⁢ ⁢E⁡(red)⁢⟶electrode⁢n⁢ ⁢E⁡(ox)+n⁢ ⁢e-(4)
Alternatively, the reactant compound E is indirectly oxidized (or reduced) using an electron transfer agent H (optionally in the presence of a catalyst), that is subsequently reduced or oxidized at the electrode, as shown in reaction equations (5) and (6). nH⁡(ox)+E⟶nH(red)+I(5)nH⁡(red)⁢⟶electrode⁢nH⁡(ox)+n⁢ ⁢e-(6)
Another example of an interferent-eliminating layer includes a catalyst for catalyzing a reaction which removes interferents. One example of such a catalyst is a peroxidase. Hydrogen peroxide reacts with interferents, such as acetaminophen, urate, and ascorbate. The hydrogen peroxide may be added to the analyte-containing fluid or may be generated in situ, by, for example, the reaction of glucose or lactate in the presence of glucose oxidase or lactate oxidase, respectively. Examples of interferent eliminating layers include a peroxidase enzyme crosslinked (a) using gluteraldehyde as a crosslinking agent or (b) oxidation of oligosaccharide groups in the peroxidase glycoenzyme with NalO4, followed by coupling of the aldehydes formed to hydrazide groups in a polyacrylamide matrix to form hydrazones are describe in U.S. Pat. Nos. 5,262,305 and 5,356,786, incorporated herein by reference.
In addition to the portions of the housing 45, such as the base 74 and cover 76, there may be other individually-formed pieces of the on-skin sensor control unit 44, which may be assembled during or after manufacture. One example of an individually-formed piece is a cover for electronic components that fits a recess in the base 74 or cover 76. Another example is a cover for a battery provided in the base 74 or cover 76. These individually-formed pieces of the on-skin sensor control unit 44 may be permanently affixed, such as, for example, a cover for electronic components, or removably affixed, such as, for example, a removable cover for a battery, to the base 74, cover 76, or other component of the on-skin sensor control unit 44. Methods for affixing these individually-formed pieces include the use of fasteners, such as screws, nuts and bolts, staples, nails, rivets, and the like, frictional fasteners, such as tongue and groove structures, and adhesives, such as contact adhesives, pressure sensitive adhesives, glues, epoxies, adhesive resins, and the like.
Another method of attaching the housing 45 of the on-skin sensor control unit 44 to the skin 75 includes using a mounting unit, 77. The mounting unit 77 is often a part of the on-skin sensor control unit 44. One example of a suitable mounting unit 77 is a double-sided adhesive strip, one side of which is adhered to a surface of the skin of the patient and the other side is adhered to the on-skin sensor control unit 44. In this embodiment, the mounting unit 77 may have an optional opening 79 which is large enough to allow insertion of the sensor 42 through the opening 79. Alternatively, the sensor may be inserted through a thin adhesive and into the skin.
The signal from the sensor 42 generally has at least one characteristic, such as, for example, current, voltage, or frequency, which varies with the concentration of the analyte. For example, if the sensor circuit 97 operates using amperometry, then the signal current varies with analyte concentration. The measurement circuit 96 may include circuitry which converts the infommation-carrying portion of the signal from one characteristic to another. For example, the measurement circuit 96 may include a current-to-voltage or current-to-frequency converter. The purpose of this conversion may be to provide a signal that is, for example, more easily transmitted, readable by digital circuits, and/or less susceptible to noise contributions.
An alternative current-to-voltage converter 141 is illustrated in FIG. 20B. This converter includes an op amp 140 with the signal from the sensor 42 provided at input terminal 144 and a reference potential provided at input terminal 142. A capacitor 145 is placed between the input terminal 144 and the output terminal 146. In addition, switches 147a, 147b, 149a, and 149b are provided to allow the capacitor to charge and discharge at a rate determined by a clock (CLK) frequency. In operation, during one half cycle, switches 147a and 147b close and switches 149a and 149b open allowing the capacitor 145 to charge due to the attached potential VI. During the other half cycle, switches 147a and 147b open and switches 149a and 149b close to ground and allow the capacitor 145 to partially or fully discharge. The reactive impedance of the capacitor 145 is analogous to the resistance of the resistor 138 (see FIG. 20A), allowing the capacitor 145 to emulate a resistor. The value of this "resistor" depends on the capacitance of the capacitor 145 and the clock frequency. By altering the clock frequency, the reactive impedance ("resistance value") of the capacitor changes. The value of the impedance ("resistance") of the capacitor 145 may be altered by changing the clock frequency. Switches 147a, 147b, 149a, and 149b may be implemented in a CMOS chip using, for example, transistors.
However, in many embodiments, the data (e.g., a current signal, a converted voltage or frequency signal, or fully or partially analyzed data) from processing circuit 109 is transmitted to one or more receiver/display units 46, 48 using a transmitter 98 in the on-skin sensor control unit 44. The transmitter has an antenna 93, such as a wire or similar conductor, formed in the housing 45. The transmitter 98 is typically designed to transmit a signal up to about 2 meters or more, preferably up to about 5 meters or more, and more preferably up to about 10 meters or more, when transmitting to a small receiver/display unit 46, such as a palm-size, belt-worn receiver. The effective range is longer when transmitting to a unit with a better antenna, such as a bedside receiver. As described in detail below, suitable examples of receiver/display units 46, 48 include units that can be easily worn or carried or units that can be placed conveniently on, for example, a nightstand when the patient is sleeping.
One potential difficulty that may be experienced with the on-skin sensor control unit 44 is a change in the transmission frequency of the transmitter 98 over time. To overcome this potential difficulty, the transmitter may include optional circuitry that can return the frequency of the transmitter 98 to the desired frequency or frequency band. One example of suitable circuitry is illustrated in FIG. 21 as a block diagram of an open loop modulation system 200. The open loop modulation system 200 includes a phase detector (PD) 210, a charge pump (CHGPMP) 212, a loop filter (L.F.) 214, a voltage controlled oscillator (VCO) 216, and a divide by M circuit (÷M) 218 to form the phase-locked loop 220.
The on-skin sensor control unit 44 may include an optional alarm system 104 that, based on the data from the processing circuit 109, warns the patient of a potentially detrimental condition of the analyte. For example, if glucose is the analyte, than the on-skin sensor control unit 44 may include an alarm system 104 that wams the patient of conditions such as hypoglycemia, hyperglycemia, impending hypoglycemia, and/or impending hyperglycemia. The alarm system 104 is triggered when the data from the processing circuit 109 reaches or exceeds a threshold value. Examples of threshold values for blood glucose levels are about 60, 70, or 80 mg/dL for hypoglycemia; about 70, 80, or 90 mg/dL for impending hypoglycemia; about 130, 150, 175, 200, 225, 250, or 275 mg/dL for impending hyperglycemia; and about 150, 175, 200, 225, 250, 275, or 300 mg/dL for hyperglycemia. The actual threshold values that are designed into the alarm system 104 may correspond to interstitial fluid glucose concentrations or electrode measurements (e.g., current values or voltage values obtained by conversion of current measurements) that correlate to the above-mentioned blood glucose levels. The analyte monitor device may be configured so that the threshold levels for these or any other conditions may be programmable by the patient and/or a medical professional.
In some embodiments, the alarm may be deactivated manually by the patient or another person in addition to or as an alternative to automatic deactivation. In these embodiments a switch 101 is provided which when activated turns off the alarm. The switch 101 may be operatively engaged (or disengaged depending on the configuration of the switch) by, for example, operating an actuator on the on-skin sensor control unit 44 or the receiver/display unit 46, 48. In some cases, an actuator may be provided on two or more units 44, 46, 48, any of which may be actuated to deactivate the alarm. If the switch 101 and or actuator is provided on the receiver/display unit 46, 48 then a signal may be transmitted from the receiver/display unit 46, 48 to the receiver 98 on the on-skin sensor control unit 44 to deactivate the alarm.
The receiver/display units 46, 48, as illustrated in block form at FIG. 22, typically include a receiver 150 to receive data from the on-skin sensor control unit 44, an analyzer 152 to evaluate the data, a display 154 to provide information to the patient, and an alarm system 156 to wam the patient when a condition arises. The receiver/display units 46, 48 may also optionally include a data storage device 158, a transmitter 160, and/or an input device 162. The receiver/display units 46,48 may also include other components (not shown), such as a power supply (e.g., a battery and/or a power supply that can receive power from a wall outlet), a watchdog circuit, a bias current generator, and an oscillator. These additional components are similar to those described above for the on-skin sensor control unit 44.
The output from the analyzer 152 is typically provided to a display 154. A variety of displays 154 may be used including cathode ray tube displays (particularly for larger units), LED displays, or LCD displays. The display 154 may be monochromatic (e.g., black and white) or polychromatic (i.e., having a range of colors). The display 154 may contain symbols or other indicators that are activated under certain conditions (e.g., a particular symbol may become visible on the display when a condition, such as hyperglycemia, is indicated by signals from the sensor 42). The display 154 may also contain more complex structures, such as LCD or LED alphanumeric structures, portions of which can be activated to produce a letter, number, or symbol. For example, the display 154 may include region 164 to display numerically the level of the analyte, as illustrated in FIG. 23. In one embodiment, the display 154 also provides a message to the patient to direct the patient in an action. Such messages may include, for example. "Eat Sugar", if the patient is hypoglycemic, or "Take Insulin", if the patient is hyperglycemic.
In yet other embodiments, the alarm may be deactivated manually by the patient or another person in addition to or as an alternative to automatic deactivation. In these embodiments, a switch is provided which when activated turns off the alarm. The switch may be operatively engaged (or disengaged depending on the configuration of the switch) by, for example, pushing a button on the receiver/display unit 46,48. One configuration of the alarm system 156 has automatic deactivation after a period of time for alarms that indicate an impending condition (e.g., impending hypoglycemia or hyperglycemia) and manual deactivation of alarms which indicate a current condition (e.g., hypoglycemia or hyperglycemia).
Friedman, Keith, Heller, Ephraim, Heller, Adam, Say, James, Gal, Yoram, Aria, Behrad, Tomasco, Michael, Vreeke, Mark, Colman, Fredric, Plante, Phillip