Reciprocating Delivery Of Fluids To The Body With Analyte Concentration Monitoring

• US 20080281290A1
• Filed: 05/07/2008
• Published: 11/13/2008
• Est. Priority Date: 05/07/2007
• Status: Active Grant

• Current Assignee: Roche Diabetes Care Inc. (Roche Holding AG)
• Original Assignee: Roche Diagnostics Operations Incorporated (Roche Holding AG)
• Inventors: Shapira, Gali, Yodfat, Ofer, Kaidar, Ruthy
• Granted Patent: US 8,814,822 B2
• Time in Patent Office: Days
• US Class Current: 604/504
• CPC Class Codes: A61B 2560/0412 Low-profile patch shaped housings
• CPC Class Codes: A61B 2560/0443 Modular apparatus
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/14865 invasive, e.g. introduced into the body by a catheter or needle or using implanted sensors
• CPC Class Codes: A61B 5/150022 for capillary blood or interstitial fluid
• CPC Class Codes: A61B 5/150229 Pumps for assisting the blood sampling
• CPC Class Codes: A61B 5/150389 Hollow piercing elements, e.g. canulas, needles, for piercing the skin
• CPC Class Codes: A61B 5/150503 Single-ended needles hollow piercing element tip design A61B5/150396, needle sets for catheters A61M25/06, needles for bringing media into the body A61M5/32
• CPC Class Codes: A61B 5/157 Devices characterised by integrated means for measuring characteristics of blood
• CPC Class Codes: A61B 5/4839 combined with drug delivery
• CPC Class Codes: A61B 5/6848 Needles
• CPC Class Codes: A61M 2005/1726 the body parameters being measured at, or proximate to, the infusion site
• CPC Class Codes: A61M 5/14248 of the skin patch type
• CPC Class Codes: A61M 5/1723 using feedback of body parameters, e.g. blood-sugar, pressure measurement of body parameters A61B5/00

Abstract

A volume of an analyte-enriched fluid can be withdrawn out of a user'"'"'s subcutaneous compartment using a patch unit that includes a reversible pumping mechanism. The volume can be withdrawn out of the body and into the patch unit through a cannula inserted into the subcutaneous compartment so that an analyte concentration in the volume can be measured using a sensing element within the patch unit. After analyte concentration analysis, at least the volume can be delivered back into the subcutaneous compartment by operating the pumping mechanism in a forward direction. biologically compatible fluid can optionally be pumped into the subcutaneous compartment from a reservoir in the patch unit and then allowed to partially or completely equilibrate with the analyte concentration in the interstitial fluid of the subcutaneous compartment via a permeable or semi-permeable cannula surface before being drawn back into the patch unit for analysis. Related systems, apparatus, methods, and/or articles are also described.

Claims

1. An apparatus comprising:

a patch unit having a skin contact surface;

a cannula having an insertable end that protrudes from the skin contact surface for insertion into a subcutaneous compartment of a user;

a detector system;

a reversible pumping mechanism for displacing fluid through the cannula; and

a control processor that controls the pumping mechanism such that the reversible pumping mechanism is configured to draw a volume of analyte-enriched fluid from the subcutaneous compartment into a sampling space and then to reverse the volume of fluid to the subcutaneous compartment after the detector system quantifies a concentration of at least one analyte in the sampling space.

2. An apparatus as in claim 1, further comprising:

a reservoir in fluid communication with the cannula and configured to contain a biologically compatible fluid, wherein the reversible pumping mechanism is configured to displace the biologically compatible fluid from the reservoir into the subcutaneous compartment via the cannula.

3. An apparatus as in claim 2, wherein the cannula comprises a dispensing arm and a sensing arm, the dispensing arm delivering the biologically compatible fluid from the reservoir into the subcutaneous compartment, the sensing arm withdrawing analyte-enriched fluid from the subcutaneous compartment to the detector system for quantifying the concentration of the at least one analyte.

4. An apparatus as in claim 3, further comprising a regulation means that prevents analyte-enriched fluid from entering the reservoir.

5. An apparatus as in claim 1, wherein the insertable end of the cannula comprises a surface that is permeable or semi-permeable such that the at least one analyte diffuses across the surface from interstitial fluid within the subcutaneous compartment to biologically compatible fluid within the cannula to create the analyte-enriched fluid.

6. An apparatus as in claim 1, wherein the insertable end of the cannula comprises a surface that is permeable such that the at least one analyte microperfuses across the surface from interstitial fluid within the subcutaneous compartment to biologically compatible fluid within the cannula such to create the analyte-enriched fluid.

7. An apparatus as in claim 1, wherein the patch unit comprises:

a disposable part that comprises the reservoir; and

a reusable part that comprises the control processor, at least part of the detector system, and at least part of the pumping mechanism, the patch unit being operable upon connection of the disposable part and reusable part.

8. An apparatus as in claim 7, further comprising a cradle unit that comprises the skin contact surface;

the cradle unit being configured to mate with the patch unit;

the patch unit being connectable to and disconnectable from the cradle unit.

9. An apparatus as in claim 7, wherein one or more components of the detector system reside in each of the reusable part and the disposable part.

10. An apparatus as in claim 7, further comprising a disposable cannula cartridge unit that comprises the cannula, the disposable cannula cartridge unit mating with the cradle unit to position the insertable end relative to the skin contact surface and providing a fluid-tight seal for interfacing with the reservoir

11. An apparatus as in claim 1, wherein the control processor initiates a change to a delivery rate of the biologically compatible fluid based on the quantified concentration of the at least one analyte.

12. An apparatus as in claim 1, wherein the control processor promotes a notification to a user interface, the notification requesting authorization of a proposed change to a delivery rate of the biologically compatible fluid based on the measured analyte concentration.

13. An apparatus as in claim 12, further comprising a remote control device comprising means for receiving fluid delivery programming commands, the remote control unit communicating with the patch unit and providing the user interface.

14. An apparatus as in claim 1, further comprising one or more buttons on the patch unit that permit entry of fluid delivery programming commands.

15. An apparatus as in claim 1, wherein the reversible pumping mechanism comprises a peristaltic mechanism or a syringe and plunger mechanism

16. An apparatus as in claim 1, wherein the patch unit further comprises a power source.

17. A method comprising:

withdrawing a volume of an analyte-enriched fluid out of a subcutaneous compartment of a user of a patch unit, the withdrawing occurring under the influence of a pumping mechanism in the patch unit, the pumping mechanism operating to displace the volume in a reverse direction, the volume being withdrawn out of the subcutaneous compartment and into the patch unit through a cannula inserted within the subcutaneous compartment;

measuring an analyte concentration in the volume using a sensing element within the patch unit; and

delivering at least the volume back into the subcutaneous compartment by operating the pumping mechanism to displace at least the volume in a forward direction.

18. A method as in claim 17, further comprising:

pumping a biologically compatible fluid from a reservoir in the patch unit into a part of the cannula insertable within the subcutaneous compartment by operating the pumping mechanism to displace the fluid in a forward direction; and

suspending fluid delivery by setting the pumping mechanism in a static state such that the biologically compatible fluid achieves a partial or complete analyte concentration equilibrium with interstitial fluids in the subcutaneous compartment, the partial or complete analyte concentration equilibrium occurring by transport of molecules of an analyte from the interstitial fluids to the biologically compatible fluid such that the biologically compatible fluid becomes the analyte-enriched fluid.

19. A method as in claim 18, wherein the cannula comprises a permeable or semi-permeable surface through which the analyte molecules diffuse during the static state.

20. A method as in claim 18, wherein the cannula comprises a permeable surface through which the analyte molecules microperfuse during the static state.

21. A method as in claim 17, further comprising:

initiating a change to a delivery rate of the biologically compatible fluid based on the measured analyte concentration.

22. A method as in claim 17, further comprising:

promoting a notification to a user interface, the notification requesting authorization of a proposed change to a delivery rate of the biologically compatible fluid based on the measured analyte concentration.

23. A method as in claim 22, wherein the user interface is provided on a remote control unit that communicates with the patch unit, the remote control unit comprising means for receiving fluid delivery programming commands.

24. A method as in claim 17, further comprising:

converting the measured analyte concentration in the analyte-enriched fluid to a calculated analyte concentration in the interstitial fluid or in a blood of the user.

25. A method as in claim 17, wherein the measuring of the analyte concentration occurs via electrochemical or optical sensing.

26. A method as in claim 17, wherein the biologically compatible fluid is insulin or saline.

27. A method as in claim 17, wherein the analyte is glucose.