Thermal system

Patent metadata

Field	Value
Publication number	US-11918510-B2
Application number	US-202117230615-A
Country	US
Kind code	B2
Filing date	Apr 14, 2021
Priority date	Nov 23, 2016
Publication date	Mar 5, 2024
Grant date	Mar 5, 2024

Abstract

A thermal control unit supplies temperature controlled fluid to one or more thermal pads used to control the temperature of a patient. The thermal control unit includes a fluid outlet, fluid inlet, heat exchanger, pump, and a controller. The controller receives first and second data from at least two different sources to determine if the patient is shivering or not. The two different sources may include a temperature sensor adapted to detect a temperature of the fluid, a temperature sensor adapted to detect a temperature of the patient, a tissue oxygenation sensor, a vibration/motion sensor, a thermal image sensor, an electromyograph, and/or other sensors. In some embodiments, the thermal control unit takes one or more automatic actions in response to detection of patient shivering.

First claim

What is claimed is:

1. A thermal control unit for controlling a patient's temperature, the thermal control unit comprising:
a fluid outlet adapted to fluidly couple to a fluid supply line;
a fluid inlet adapted to fluidly couple to a fluid return line;
a heat exchanger;
a pump for circulating fluid from the fluid inlet through the heat exchanger and to the fluid outlet; and
a controller adapted to receive first data from a first source and second data from a second source, the controller further adapted to use both the first data and the second data to determine if the patient is shivering, the controller further adapted to perform the following
(i) notify a user that the patient is shivering only if the first data exceeds a first threshold and the second data exceeds a second threshold; and
(ii) not notify the user that the patient is shivering if either (a) the first data exceeds the first threshold but the second data does not exceed the second threshold, or (b) the second data exceeds the second threshold but the first data does not exceed the first threshold.

2. The thermal control unit of claim 1 wherein the first source is a sensor adapted to detect vibrations.

3. The thermal control unit of claim 2 wherein the second source includes at least one of the following: a tissue oxygenation sensor adapted to detect changes in oxygenation levels in the patient's tissue; a temperature sensor adapted to detect a temperature of the circulating fluid; and a temperature sensor adapted to detect a temperature of the patient.

4. The thermal control unit of claim 2 wherein the second source includes a temperature sensor adapted to detect at least one of the following: a temperature of the circulating fluid and a temperature of the patient; and
wherein the controller is adapted to analyze temperature readings from the temperature sensor and identify at least one of the following: if additional energy necessitated by the patient's shivering is being used by the thermal control unit to cool the patient, or if a rate of cooling of the patient changes due to the patient's shivering.

5. The thermal control unit of claim 1 wherein the first source is a first one of, and the second source is a second one of, the following group: a sensor adapted to detect vibrations; a tissue oxygenation sensor adapted to detect changes in oxygenation levels in the patient's blood; a temperature sensor adapted to detect temperature changes in the circulating fluid; a temperature sensor adapted to detect temperature changes in the patient; a thermal image sensor adapted to capture thermal images of the patient; and an electromyograph adapted to detect electrical activity in the patient's muscles.

6. The thermal control unit of claim 3 wherein the tissue oxygenation sensor is coupled to a thermal pad fluidly coupled to the fluid supply line and fluid return line such that the tissue oxygenation sensor senses oxygenation levels in a region of the patient's body adjacent to the thermal pad.

7. The thermal control unit of claim 1 wherein the controller is further adapted to take an action in response to a determination that the patient is shivering, the action being configurable by a user of the thermal control unit.

8. The thermal control unit of claim 1 wherein the thermal control unit includes a first cooling mode and a second cooling mode selectable by a user of the thermal control unit, the first cooling mode cooling the patient in a first manner and the second cooling mode cooling the patient in a second manner.

9. The thermal control unit of claim 8 wherein the controller is configurable by a user to automatically take a first action in response to a determination that the patient is shivering while the thermal control unit is operating in the first cooling mode, and to automatically take a second action in response to a determination that the patient is shivering while the thermal control unit is operating in the second cooling mode.

10. The thermal control unit of claim 9 wherein the first action includes adjusting a control signal sent to the heat exchanger in response to the determination that the patient is shivering, and the second action includes notifying the user of the determination that the patient is shivering without adjusting the control signal sent to the heat exchanger.

11. The thermal control unit of claim 7 wherein the action includes automatically warming a selected region of the patient's body while continuing to deliver circulating fluid to the fluid outlet at a temperature less than the patient's body temperature.

12. The thermal control unit of claim 2 wherein the controller is further adapted to receive third data from a third source and also use the third data to determine if the patient is shivering.

13. The thermal control unit of claim 12 wherein the second source is a first temperature sensor adapted to detect a temperature of the circulating fluid and the third source is a second temperature sensor adapted to detect a temperature of the patient.

Assignees

• Stryker Corp

Inventors

• Taylor Gregory S
• Kostic Marko N
• Constant Marco
• Hopper Christopher John

Classifications

• A61F7/0085 Primary

  Devices for generating hot or cold treatment fluids · CPC title

• A61B5/0036

  including treatment, e.g., using an implantable medical device, ablating, ventilating · CPC title

• A61B5/01

  Measuring temperature of body parts {; Diagnostic temperature sensing, e.g. for malignant or inflamed tissue} (clinical contact thermometers G01K13/20) · CPC title

• A61B5/1101

  Detecting tremor · CPC title

• A61B5/14542

  for measuring blood gases (A61B5/14551 takes precedence) · CPC title