Combined sensor and infusion set using separated sites

• US 20090062767A1
• Filed: 08/29/2007
• Published: 03/05/2009
• Est. Priority Date: 08/29/2007
• Status: Active Grant

• Current Assignee: Medtronic Minimed Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Minimed Incorporated (Medtronic Plc)
• Inventors: Lemos, Richard JR., Phou, Ly, Voskanyan, Gayane R., Shah, Rajiv, Enegren, Bradley J., Van Antwerp, Nannette M., Steil, Garry M.
• Granted Patent: US 9,968,742 B2
• Time in Patent Office: Days
• US Class Current: 604/504
• CPC Class Codes: A61B 5/0031 Implanted circuitry
• CPC Class Codes: A61B 5/14503 invasive, e.g. introduced into the body by a catheter or needle or using implanted sensors A61B5/1459, A61B5/1464, A61B5/1473, A61B5/1482, A61B5/14865 take precedence
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/14546 for measuring analytes not otherwise provided for, e.g. ions, cytochromes
• CPC Class Codes: A61B 5/1473 invasive, e.g. introduced into the body by a catheter A61B5/1482 takes precedence
• CPC Class Codes: A61B 5/1486 using enzyme electrodes, e.g. with immobilised oxidase
• CPC Class Codes: A61B 5/4839 combined with drug delivery
• CPC Class Codes: A61B 5/6846 specially adapted to be brought in contact with an internal body part, i.e. invasive
• CPC Class Codes: A61B 5/6848 Needles
• CPC Class Codes: A61B 5/6849 in combination with a needle set
• CPC Class Codes: A61M 2005/14252 with needle insertion means
• CPC Class Codes: A61M 2005/1585 Needle inserters
• CPC Class Codes: A61M 2005/1586 Holding accessories for holding infusion needles on the body holding devices for catheters A61M25/02
• CPC Class Codes: A61M 2005/1587 suitable for being connected to an infusion line after insertion into a patient
• CPC Class Codes: A61M 2005/1726 the body parameters being measured at, or proximate to, the infusion site
• CPC Class Codes: A61M 2230/201 Glucose concentration
• CPC Class Codes: A61M 5/14248 of the skin patch type
• CPC Class Codes: A61M 5/158 Needles for infusions; Accessories therefor, e.g. for inserting infusion needles, or for holding them on the body
• CPC Class Codes: A61M 5/172 electrical or electronic A61M5/16804, A61M5/16831 take precedence
• CPC Class Codes: A61M 5/1723 using feedback of body parameters, e.g. blood-sugar, pressure measurement of body parameters A61B5/00

Abstract

Embodiments of the invention provide a dual insertion set for supplying a fluid to the body of a patient and for monitoring a body characteristic of the patient. Typical embodiments of the invention include a base, an infusion portion coupled to a first piercing member and a sensor portion coupled to a second piercing member. The infusion portion includes a cannula coupled to the piercing member for supplying a fluid to a placement site. The sensor portion includes a sensor coupled to and extending from the base having at least one sensor electrode formed on a substrate and is coupled to the piercing member in a manner that allows the sensor to be inserted at the placement site. The base is arranged to secure the dual insertion set to the skin of a patient. Typically the infusion portion and sensor portion piercing members are arranged such that when they are operatively coupled to the base, they are disposed in a spatial orientation designed to inhibit sensor interference that may be caused by compounds present in fluids infused through the cannula.

Claims

1. An apparatus for supplying a fluid to a body of a patient and for monitoring a body characteristic of the patient, the apparatus comprising:

a base adapted to secure the apparatus to the skin of a patient;

a first piercing member coupled to and extending from the base, wherein the first piercing member is operatively coupled to at least one cannula for infusing a fluid to an infusion site;

a second piercing member coupled to and extending from the base and operatively coupled to an electrochemical sensor having a sensor electrode for determining at least one body characteristic of the patient at a sensor placement site;

wherein the first and second piercing members are coupled to the base in an orientation such that when the first and second piercing members are operatively coupled to the base and inserted into a patient, a first perforation channel made by the first piercing member is not in operable contact with a second perforation channel made by the second piercing member.

2. The apparatus of claim 1, wherein the first and second piercing members are coupled to the base in an orientation such that when the first and second piercing members are inserted into a patient, the infusion site is disposed within a layer of the epidermis and the sensor electrode is disposed within a layer of the dermis.

3. The apparatus of claim 1, wherein the first and second piercing members are coupled to the base in an orientation such that when the first and second piercing members are inserted into a patient, the infusion site and the sensor electrode are separated by at least 7 millimeters of tissue.

4. The apparatus of claim 1, wherein the first and second piercing members are disposed on a hub that can operatively engage and disengage from the base.

5. The apparatus of claim 4, wherein the hub comprises a finger grip member that allows the hub to be gripped as it is disengaged from the base.

6. The apparatus of claim 1, wherein the first and second piercing members are coupled to the base in an orientation so that when the cannula and the sensor electrode are disposed in a patient, the cannula and the sensor electrode anchor the apparatus to the skin of the patient, thereby stabilizing sensor readings.

7. The apparatus of claim 1, wherein the first and second piercing members are metal needles.

8. The apparatus of claim 1, further comprising infusion set tubing adapted to connect to the cannula.

9. The apparatus of claim 8, further comprising a medication infusion pump adapted to connect to the infusion set tubing.

10. The apparatus of claim 1, wherein the first piercing member is shorter than the second piercing member.

11. The apparatus of claim 1, wherein the fluid is insulin.

12. The apparatus of claim 1, wherein a monitored body characteristic comprises blood glucose.

13. The apparatus of claim 1, wherein the apparatus is in a modular configuration that allows the cannula and the sensor to be replaced independently of other components of the apparatus.

14. The apparatus of claim 1, further comprising an array of microneedles for infusing a fluid to an infusion site.

15. The apparatus of claim 1, wherein the sensor comprises a plurality of layers, wherein at least one of the layers comprises:

a base substrate on which the electrode is disposed, the base substrate including a geometric feature selected to increase the surface area of an electrochemically reactive surface on the electrode disposed thereon such that surface area to volume ratio of the electrochemically reactive surface area of the electrode disposed on the geometric feature is greater than surface area-to-volume ratio of the reactive surface of the electrode when disposed on a flat surface;

an analyte sensing layer that detectably alters the electrical current at the electrode in the presence of an analyte;

an adhesion promoting layer that promotes the adhesion between one or more layers of the sensor;

an analyte modulating layer that modulates the diffusion of a analyte therethrough;

or

a cover layer that is impermeable to blood glucose, wherein the cover layer includes an aperture.

16. A method for inhibiting interference of an electrochemical sensor that monitors a body characteristic of a patient, wherein the interference is caused by a interferant present in an infusate infused by an apparatus for supplying a fluid to a body of a patient, the method comprising supplying a fluid to a body of a patient using an apparatus comprising:

a base adapted to secure the apparatus to the skin of a patient;

a first piercing member coupled to and extending from the base, wherein the first piercing member comprises at least one cannula for infusing a fluid to an infusion site,

a second piercing member coupled to and extending from the base and including the electrochemical sensor having a sensor electrode for determining at least one body characteristic of the patient at a sensor placement site,

wherein the first and second piercing members are coupled to the base in an orientation such that when the first and second piercing members are inserted into a patient, a first perforation channel made by the first piercing member is not in operable contact with a second perforation channel made by the second piercing member such that a fluid infused to the infusion site cannot flow through the first perforation channel or the second perforation channel to the sensor;

so that interference is inhibited.

17. The method of claim 16, further comprising the method of stabilizing the apparatus to the skin of the patient comprising the step of using an apparatus where the first and second piercing members are coupled to the base in an orientation so that when the cannula and the sensor electrode are disposed in a patient, they function to anchor the apparatus to the skin of the patient.

18. The method of claim 16, wherein the interference is caused by a phenolic preservative present in the infusate.

19. The method of claim 16, wherein the sensor comprises a plurality of layers, wherein at least one of the layers comprises:

a base substrate on which the electrode is disposed, the base substrate including a geometric feature selected to increase the surface area of an electrochemically reactive surface on the electrode disposed thereon such that surface area to volume ratio of the electrochemically reactive surface area of the electrode disposed on the geometric feature is greater than surface area-to-volume ratio of the reactive surface of the electrode when disposed on a flat surface;

an analyte sensing layer that detectably alters the electrical current at the electrode in the presence of an analyte;

an adhesion promoting layer that promotes the adhesion between one or more layers of the sensor;

an analyte modulating layer that modulates the diffusion of a analyte therethrough;

or

a cover layer that is impermeable to blood glucose, wherein the cover layer includes an aperture.

20. An apparatus for supplying a fluid to a body of a patient and for monitoring a body characteristic of the patient, the apparatus comprising:

a base adapted to secure the apparatus to the skin of a patient;

a piercing member coupled to and extending from the base and having a first and a second lumen;

wherein

the first lumen comprises an outlet adapted to infuse a fluid to an infusion site;

the second lumen comprises an electrochemical sensor disposed therein, wherein the electrochemical sensor comprises a sensor electrode for determining at least one body characteristic of the patient at a sensor placement site and a window that exposes the sensor to the body of the patient; and

the outlet of the first lumen and the window of the second lumen are arranged in an orientation such that when the piercing member is operatively coupled to the base and inserted into a patient, an infusate is infused from the orifice at a site that is least 7 millimeters from the window of the second lumen.

21. The apparatus of claim 20, wherein the outlet of the first lumen and the window of the second lumen are arranged in an orientation such that the window of the second lumen is closer to the base than is the outlet of the first lumen.

22. The apparatus of claim 20, wherein the piercing member is a metal needle that is operatively coupled to a catheter that delivers a fluid medication from a fluid reservoir through the outlet of the first lumen to the infusion site.

23. The apparatus of claim 22, further comprising infusion set tubing adapted to connect to the cannula and a medication infusion pump adapted to connect to the infusion set tubing.

24. The apparatus of claim 20, wherein the sensor comprises a plurality of layers, wherein at least one of the layers comprises:

a base substrate on which the electrode is disposed, the base substrate including a geometric feature selected to increase the surface area of an electrochemically reactive surface on the electrode disposed thereon such that surface area to volume ratio of the electrochemically reactive surface area of the electrode disposed on the geometric feature is greater than surface area-to-volume ratio of the reactive surface of the electrode when disposed on a flat surface;

an analyte sensing layer that detectably alters the electrical current at the electrode in the presence of an analyte;

an adhesion promoting layer that promotes the adhesion between one or more layers of the sensor;

an analyte modulating layer that modulates the diffusion of a analyte therethrough;

or

a cover layer that is impermeable to blood glucose, wherein the cover layer includes an aperture.

25. The apparatus of claim 20, wherein the fluid is insulin and a monitored body characteristic comprises blood glucose.