Methods and devices for measuring core body temperature

• US 9,410,854 B2
• Filed: 02/15/2008
• Issued: 08/09/2016
• Est. Priority Date: 03/15/2007
• Status: Active Grant

• Current Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Original Assignee: Koninklijke Philips N.V.
• Inventors: Padiy, Alexander V.
• Primary Examiner(s): Towa, Rene
• Assistant Examiner(s): NGUYEN, HUONG Q
• Application Number:
  US12/531,313
• Publication Number:
  US 20100113894A1
• Time in Patent Office: 3,098 Days
• Field of Search: 600/549
• US Class Current: 1/1
• CPC Class Codes: A61B 2562/0271 Thermal or temperature sensors
• CPC Class Codes: A61B 5/0002 Remote monitoring of patients using telemetry, e.g. transmission of vital signals via a communication network A61B5/07 takes precedence; transmission systems for measured values G08C; transmission H04B; transmission of digital information H04L; wireless communication networks H04W
• CPC Class Codes: A61B 5/015 By temperature mapping of body part
• 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 5/4064 Evaluating the brain A61B5/031, A61B5/369, A61B5/14553 take precedence
• CPC Class Codes: A61B 5/6814 Head
• CPC Class Codes: A61B 5/6815 Ear
• CPC Class Codes: A61B 5/6833 Adhesive patches
• CPC Class Codes: A61B 5/6838 Clamps or clips
• CPC Class Codes: G01K 1/026 arrangements for monitoring a plurality of temperatures, e.g. by multiplexing
• CPC Class Codes: G01K 1/16 Special arrangements for conducting heat from the object to the sensitive element
• CPC Class Codes: G01K 13/20 Clinical contact thermometers for use with humans or animals
• CPC Class Codes: G01K 7/42 Circuits effecting compensation of thermal inertia; Circuits for predicting the stationary value of a temperature

Abstract

A core body temperature measurement device includes a plurality of electronic temperature sensors (12, 12f, 12b, 132) operatively coupled with or near a surface (STA, PAA, BTT) having a surface temperature approximating the core body temperature, and a readout controller (10, 48, 68, 90, 124) including a maximum temperature reading selector (14). The readout controller is configured to acquire temperature readings using the plurality of temperature sensors and to output a core body temperature based on a highest usable temperature reading of the acquired temperature readings as determined by the maximum temperature reading selector. A core body temperature measurement method includes: acquiring a plurality of temperature readings at and near a surface (STA, PAA, BTT) having a surface temperature approximating the core body temperature; generating a highest usable temperature reading from the acquired temperature readings; and outputting a core body temperature based on the highest usable temperature.

Claims

1. A physiological sensor device for measuring core body temperature of a subject, the physiological sensor device comprising:

a plurality of electronic temperature sensors wherein each electronic temperature sensor includes a first conductive body arranged to be placed in thermal contact with a surface having a surface temperature approximate the core body temperature of the subject and a second conductive body spaced apart from the first conductive body and the surface by a dielectric disposed between the first and second conductive bodies, a first temperature sensor configured to measure the temperature of the first conductive body, a second temperature sensor configured to measure the temperature of the second conductive body, actuators configured to control separation of the spaced-apart first and second conductive bodies, a capacitance meter configured to measure mutual capacitance of the spaced-apart first and second conductive bodies with the dielectric disposed between the first and second conductive bodies; and

a readout controller comprising a microchip configured to, for each electronic temperature sensor;

receive measurements of the respective temperatures of the spaced-apart first and second conductive bodies from the first and second temperature sensors and measurement of a mutual capacitance of the spaced apart first and second conductive bodies from the capacitance meter for a plurality of different separations of the spaced-apart first and second conductive bodies controlled using the actuators,

estimate a skin temperature drop based on received measurements of the respective temperatures of the spaced-apart first and second conductive bodies and of the mutual capacitance at the different separations of the spaced-apart first and second conductive bodies, and

correct the received temperature of the first conductive body for the estimated skin temperature drop to generate a temperature reading from the electronic temperature sensor, wherein the readout controller is further configured to output a core body temperature based on a highest usable temperature reading of the acquired temperature readings.

2. The physiological sensor device as set forth in claim 1, wherein the plurality of electronic temperature sensors are configured to be operatively coupled with said surface selected from the group consisting of:

(i) skin overlaying a portion of a superficial temporal artery disposed anterior to an auricle, (ii) skin overlaying a portion of an artery ascending posterior to an auricle, and (iii) a brain tunnel between the eyes.

3. The physiological sensor device as set forth in claim 1, further comprising:

a head mountable mechanical frame or pad configured to operatively couple the electronic temperature sensors with said surface having a surface temperature approximating the core body temperature.

4. The physiological sensor device as set forth in claim 1, wherein the readout controller is configured to identify the highest usable temperature reading of the acquired temperature readings by

spatial interpolation of temperature readings of the plurality of electronic temperature sensors to generate an interpolation;

and

detection of the highest usable temperature reading of the acquired temperature readings as a peak of the interpolation.

5. The physiological sensor device as set forth in claim 4, wherein the interpolation is one of (i) a two dimensional interpolated temperature surface and (ii) a one dimensional interpolated temperature versus position curve.

6. A core body temperature measurement device for measuring core body temperature of a subject, the core body temperature measurement device comprising:

spaced-apart first and second conductive bodies configured to be arranged with the first conductive body in thermal contact with a surface having a surface temperature approximate the core body temperature of the subject and the second conductive body spaced apart from the first conductive body and the surface by a dielectric disposed between the first and second conductive bodies;

a first temperature sensor configured to measure the temperature of the first conductive body;

a second temperature sensor configured to measure the temperature of the second conductive body;

actuators configured to control separation of the spaced-apart first and second conductive bodies;

a capacitance meter configured to measure mutual capacitance of the spaced-apart first and second conductive bodies with the dielectric disposed between the first and second conductive bodies; and

a controller comprising a microchip configured to;

(i) receive measurements of the respective temperatures of the spaced-apart first and second conductive bodies from the first and second temperature sensors,

(ii) receive measurement of a mutual capacitance of the spaced apart first and second conductive bodies from the capacitance meter,

(iii) repeat operations (i) and (ii) for a plurality of different separations of the spaced-apart first and second conductive bodies controlled using the actuators,

(iv) estimate a skin temperature drop based on received measurements of the respective temperatures of the spaced-apart first and second conductive bodies and of the mutual capacitance at the different separations of the spaced-apart first and second conductive bodies;

(v) correct the received temperature of the first conductive body for the estimated skin temperature drop to generate a measurement of the core body temperature.

7. The core body temperature measurement device as set forth in claim 6, wherein the core body temperature measurement device is configured to be operatively coupled with said surface selected from the group consisting of:

skin overlaying a portion of a superficial temporal artery disposed anterior to an auricle, skin overlaying a portion of an artery ascending posterior to an auricle, a brain tunnel between the eyes; and

a sublingual pocket inside of a mouth.

8. The core body temperature measurement device as set forth in claim 6, comprising a head mountable mechanical frame or pad configured to place the first conductive body in thermal contact with said surface.

9. A core body temperature measurement device for measuring core body temperature of a subject, the core body temperature measurement device comprising:

a first conductive body arranged to be placed in thermal contact with a surface having a surface temperature approximate the core body temperature of the subject;

a second conductive body spaced apart from the first conductive body and the surface by a dielectric disposed between the first and second conductive bodies;

actuators configured to control separation of the spaced-apart first and second conductive bodies;

temperature sensors configured to measure temperature of the first conductive body and to measure temperature of the second conductive body;

a capacitance meter configured to measure mutual capacitance of the spaced-apart first and second conductive bodies with the dielectric disposed between the first and second conductive bodies; and

a readout controller comprising a microchip, the readout controller configured to;

(i) estimate a skin temperature drop based on mutual capacitance

of the spaced-apart first and second conductive bodies measured by the capacitance meter and temperatures of the first and second conductive bodies measured by the temperature sensors at different separations of the spaced-apart first and second conductive bodies; and

(ii) correct the measured temperature of the first conductive body for the estimated skin temperature drop to generate a measurement of the core body temperature.

10. The core body temperature measurement device of claim 9 wherein the actuators include piezoelectric, inchworm, or MEMS actuators configured to control separation of the spaced-apart first and second conductive bodies.

11. The core body temperature measurement device of claim 9 wherein the temperature sensors include:

a first thermocouple configured to measure temperature of the first conductive body; and

a second thermocouple configured to measure temperature of the second conductive body.

12. The core body temperature measurement device of claim 9 wherein at least one of the first conductive body and the second conductive body includes a protrusion extending toward the other of the first conductive body and the second conductive body.