Inverted sensor module

• US 6,918,873 B1
• Filed: 09/19/2002
• Issued: 07/19/2005
• Est. Priority Date: 09/19/2002
• Status: Active Grant

• Current Assignee: Millar Instruments
• Original Assignee: Millar Instruments
• Inventors: Bendele, Travis H., Gray, Stephen P., Millar, Huntly D.
• Primary Examiner(s): WINAKUR, ERIC FRANK
• Application Number:
  US10/247,777
• Time in Patent Office: 1,034 Days
• Field of Search: 600/309, 600/310, 600/316, 600/322, 600/323, 600/339, 600/341, 600/364, 600/365, 600/481, 600/485, 600/486, 600/504, 600/505, 600/506, 600/547, 600/549
• US Class Current: 600/309
• CPC Class Codes: A61B 5/0031 Implanted circuitry
• CPC Class Codes: A61B 5/0215 by means inserted into the body catheters A61M25/00
• CPC Class Codes: A61B 5/026 Measuring blood flow A61B3/1233, A61B3/1241 take precedence
• CPC Class Codes: A61B 5/145 Measuring characteristics of blood in vivo, e.g. gas concentration, pH value; Measuring characteristics of body fluids or tissues, e.g. interstitial fluid, cerebral tissuemeasuring of blood pressure or blood flow A61B5/02; non-radiation detecting or locating of foreign bodies in blood A61B5/06
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/418 lymph vessels, ducts or nodes
• CPC Class Codes: A61B 5/6876 Blood vessel
• CPC Class Codes: A61B 5/6884 Clamps or clips

Abstract

An inverted sensor module for sensing physical and chemical fluid characteristics in a vessel in a living body. The inverted sensor module includes an inverted sensor bonded to a hollow carrier so that sensing occurs in the lumen of the inverted sensor module. An inverted sensor module comprising one or more inverted sensors is implantable and allows fluid to flow through, thereby allowing for measurements of acute and chronic conditions. The inverted sensor module may be used in series with other inverted sensor modules to assess trends such as pressure gradients along a bloodstream.

Claims

1. An inverted sensor module for sensing one or more characteristics of fluid in one or more vessels in a living body, the inverted sensor module comprising;

a sensor carrier having one or more openings, wherein said sensor carrier is sized for insertion within said one or more vessels, and wherein an inner surface of said sensor carrier is coated or lined with a substance for reducing turbulence of the fluid flowing through a lumen of said sensor carrier;

one or more sensors mounted to said sensor carrier, such that a sensing side of said one or more sensors is exposed to the inside of said sensor carrier through said one or more openings;

a surface feature formed on each end of said inverted sensor module, such that the ends of a cut vessel may be attached to both ends of said inverted sensor module; and

communication media operatively connected to said one or more sensors, said communication media operable for communicating sensor information to a monitoring device.

2. The inverted sensor module of claim 1, wherein said one or more sensors sense one or more physical characteristics of said fluid.

3. The inverted sensor module of claim 2, wherein said one or more characteristics comprises flow velocity.

4. The inverted sensor module of claim 2, wherein said one or more characteristics comprises pressure.

5. The inverted sensor module of claim 2, wherein said one or more characteristics comprises temperature.

6. The inverted sensor module of claim 2, wherein said one or more characteristics comprises conductance.

7. The inverted sensor module of claim 1, wherein said one or more sensors sense one or more chemical characteristics of said fluid.

8. The inverted sensor module of claim 7, wherein said one or more characteristics comprises pH.

9. The inverted sensor module of claim 7, wherein said one or more characteristics comprises O₂ concentration.

10. The inverted sensor module of claim 7, wherein said one or more characteristics comprises CO₂ concentration.

11. The inverted sensor module of claim 7, wherein said one or more characteristics comprises glucose concentration.

12. The inverted sensor module of claim 1, wherein the communication media are coupled to the one or more sensors with wires, fiber optics, or telemetry.

13. The inverted sensor module of claim 1, further comprising a portion of tubing bonded to said inverted sensor module such that fluids may flow through said inverted sensor module, wherein said inverted sensor module is operable to detect the one or more characteristics of the fluid flowing through said inverted sensor module.

14. The inverted sensor module of claim 13, wherein said surface feature on each end of said inverted sensor module comprises a groove.

15. The inverted sensor module of claim 13, wherein said surface feature on each end of said inverted sensor module comprises a lip.

16. The inverted sensor module of claim 13, wherein said surface feature on each end of said inverted sensor module comprises a knurl.

17. The inverted sensor module of claim 13, wherein said surface feature on each end of said inverted sensor module comprises a chemical etch.

18. The inverted sensor module of claim 13, further comprising a protective housing for said sensor.

19. The inverted sensor module of claim 13, wherein said one or more vessels in said living body comprise blood vessels, lymph vessels, ureters, intestines or chambers of the heart.

20. The inverted sensor module of claim 1, wherein said substance comprises an antithrombogenic substance, which is applied to the inner surface of the sensor carrier to reduce blood clotting within the sensor carrier and to produce a completely smooth surface.

21. The inverted sensor module of claim 1, wherein said substance comprises an anti-infective agent, which is applied to the inner surface of the sensor carrier to reduce a possibility for infection and to produce a completely smooth surface.

22. The inverted sensor module of claim 1, wherein said sensor carrier is formed from a rigid biocompatible material selected from stainless steel, platinum, titanium, ceramic and a rigid polymer-based tubing.

23. The inverted sensor module of claim 22, wherein said one or more sensors are mounted to said sensor carrier with a plant bonding material that provides at least some electrical isolation from said sensor carrier.

24. A method for determining fluid characteristics in a living body using an inverted sensor module, comprising the steps of:

opening a fluid vessel in the living body, wherein said vessel is scored or cut;

inserting an inverted sensor module, comprising one or more sensors, into said vessel; and

closing said vessel such that all fluid flow through said vessel passes through said inverted sensor module, wherein said closing comprises connecting cut surfaces of the vessel to surface features formed at opposing ends of said inverted sensor module, and wherein said inverted sensor module is operable to sense fluid characteristics and send information about said fluid characteristics to a monitoring device outside the living body.

25. The method of claim 24, further comprising the step of operably connecting said one or more inverted sensor modules via one or more communication media to a monitoring device located outside the living body.

26. A method for manufacturing an inverted sensor module configured for insertion within a living body, wherein the method comprises the steps of:

machining one or more openings into a sensor carrier;

bonding one or more sensors into said one or more openings machined into said sensor carrier such that a sensing side of said one or more sensors is exposed toward a concave side of said sensor carrier; and

creating a surface feature of an end of said inverted sensor module such that a vessel located within the living body may be connected to said inverted sensor module.

27. The method of claim 26, further comprising the steps of:

applying an antithrombogenic substance to said sensing side of said one or more sensors; and

connecting communication media to said sensor.

28. The method of claim 26, further comprising the step of bonding a portion of tubing to said inverted sensor module, such that fluids may flow through a lumen of said inverted sensor module.

29. The method of claim 28, further comprising the step of creating a surface feature on an end of said inverted sensor module such that tubing may be connected to said inverted sensor module.

30. The method of claim 28, further comprising the step of bonding a protective housing to said inverted sensor module.