MEDICAL TEMPERATURE SENSORS AND RELATED SYSTEMS AND METHODS

• US 20120277673A1
• Filed: 04/26/2011
• Published: 11/01/2012
• Est. Priority Date: 04/26/2011
• Status: Active Grant

• Current Assignee: Fresenius Medical Care Holdings Incorporated (Fresenius Medical Care AG)
• Original Assignee: Fresenius Medical Care Holdings Incorporated (Fresenius Medical Care AG)
• Inventors: Levin, Roland, Crnkovich, Martin Joseph
• Granted Patent: US 8,353,870 B2
• Time in Patent Office: Days
• US Class Current: 604/113
• CPC Class Codes: A61M 1/14 Dialysis systems; Artificial kidneys; Blood oxygenators semi-permeable membranes characterised by the material, manufacturing processes therefor B01D71/00; Reciprocating systems for treatment of body fluids, e.g. single needle systems for hemofiltration or pheresis
• CPC Class Codes: A61M 1/16 with membranes
• CPC Class Codes: A61M 1/1605 Physical characteristics of the dialysate fluid
• CPC Class Codes: A61M 1/1664 with temperature control
• CPC Class Codes: A61M 1/36 Other treatment of blood in a by-pass of the natural circulatory system, e.g. temperature adaptation, irradiation ; Extra-corporeal blood circuits
• CPC Class Codes: A61M 1/3612 after treatment
• CPC Class Codes: A61M 1/367 Circuit parts not covered by the preceding subgroups of group A61M1/3621
• CPC Class Codes: A61M 1/369 Temperature treatment
• CPC Class Codes: A61M 2205/3306 Optical measuring means
• CPC Class Codes: A61M 2205/3368 Temperature
• CPC Class Codes: A61M 2205/3372 Temperature compensation
• CPC Class Codes: A61M 2205/36 related to heating or cooling

Abstract

This disclosure relates to medical temperature sensors and related systems and methods. In some aspects, a sensor assembly includes a non-invasive temperature sensor to detect a temperature of a medical fluid in a medical fluid line and an ambient temperature sensor to detect an ambient air temperature.

Claims

1. A method comprising:

detecting a temperature of a medical fluid in tubing using a non-invasive fluid temperature sensor;

transmitting the detected temperature of the medical fluid to a control unit;

detecting a temperature of ambient air using an ambient air temperature sensor;

transmitting the detected temperature of the ambient air to the control unit; and

using the control unit to calculate a corrected medical fluid temperature based on the detected temperatures of the medical fluid and the ambient air.

2. The method of claim 1, wherein the medical fluid is blood.

3. The method of claim 2, wherein the control unit is a control unit of a hemodialysis machine.

4. The method of claim 1, wherein calculating the corrected medical fluid temperature comprises referencing a look-up table that provides a corrected medical fluid temperature for each of multiple different combinations of detected temperatures of medical fluid and detected temperatures of ambient air.

5. The method of claim 1, wherein calculating the corrected medical fluid temperature comprises inputting the detected temperatures of the medical fluid and the ambient air into an equation to obtain the corrected medical fluid temperature.

6. The method of claim 1, wherein calculating the corrected medical fluid temperature comprises running a statistical analysis to obtain the corrected medical fluid temperature.

7. The method of claim 1, further comprising determining a plurality of corrected medical fluid temperatures for a plurality of different combinations of medical fluid temperatures and ambient air temperatures and storing the plurality of corrected medical fluid temperatures in the control unit.

8. The method of claim 7, wherein determining the plurality of corrected medical fluid temperatures comprises detecting temperatures of a test fluid using an invasive, temperature sensor.

9. The method of claim 8, wherein determining the plurality of corrected medical fluid temperatures further comprises altering the temperature of the test fluid and ambient air during a test period.

10. The method of claim 1, wherein the non-invasive sensor is an infrared sensor.

11. The method of claim 10, wherein detecting the temperature of the medical fluid comprises transmitting an infrared signal through the tubing and the medical fluid and then receiving the infrared signal.

12. The method of claim 1, wherein the non-invasive fluid temperature sensor and the ambient air temperature sensor are mounted to a single housing.

13. The method of claim 1, wherein the housing defines a slot configured to receive a portion of the tubing therein.

14. The method of claim 1, wherein the non-invasive fluid temperature sensor is configured to contact the portion of the tubing when the portion of the tubing is disposed in the slot of the housing.

15. A medical sensor assembly comprising:

a housing defining a slot to retain a medical fluid line;

a non-invasive fluid temperature sensor mounted to the housing and configured to detect a temperature of medical fluid in the medical fluid line when the medical fluid line is disposed in the slot and the medical fluid is flowing through the medical fluid line; and

an ambient air temperature sensor mounted to the housing.

16. The medical sensor assembly of claim 15, wherein the medical fluid line is a blood line.

17. The medical sensor assembly of claim 15, wherein the ambient air temperature sensor is mounted to an outer surface of the housing.

18. The medical sensor assembly of claim 17, wherein the non-invasive fluid temperature sensor is mounted to an inner surface of the housing such that the non-invasive fluid temperature sensor is adjacent the medical fluid line when the medical fluid line is disposed in the slot.

19. The medical sensor assembly of claim 18, wherein the non-invasive fluid temperature sensor is positioned to contact the medical fluid line when the medical fluid line is disposed in the slot.

20. The medical sensor assembly of claim 15, wherein the non-invasive fluid temperature sensor is positioned in the slot in the housing.

21. The medical sensor assembly of claim 15, wherein the non-invasive fluid temperature sensor is an infrared temperature sensor.

22. A medical fluid pumping system comprising

a medical fluid pumping machine comprising a pump;

fluid circuitry comprising tubing that can be connected to the pump in a manner such that the pump can move a medical fluid through the tubing of the fluid circuitry; and

a sensor assembly comprising

a housing defining a slot to retain a portion of tubing of the fluid circuitry;

a non-invasive fluid temperature sensor mounted to the housing and configured to detect a temperature of medical fluid in the portion of tubing of the fluid circuitry when the portion of tubing is disposed in the slot and the medical fluid is flowing through the portion of tubing; and

an ambient air temperature sensor mounted to the housing.

23. The medical fluid pumping system of claim 22, wherein the medical fluid pumping machine is a dialysis machine.

24. The medical fluid pumping system of claim 23, wherein the medical fluid is blood.

25. The medical fluid pumping system of claim 22, wherein the medical fluid pumping machine comprises a control unit that is in communication with the non-invasive fluid temperature sensor and the ambient air temperature sensor.

26. The medical fluid pumping system of claim 25, wherein the control unit comprises a look-up table that provides a corrected medical fluid temperature for each of multiple different combinations of temperatures of medical fluid detected by the non-invasive fluid temperature sensor and temperatures of ambient air detected by the ambient air temperature sensor.

27. The medical fluid pumping system of claim 25, wherein the control unit comprises an equation to obtain a corrected medical fluid temperature based on a temperature of medical fluid detected by the non-invasive fluid temperature sensor and a temperature of ambient air detected by the ambient air temperature sensor.

28. The medical fluid pumping system of claim 25, wherein the control unit is adapted to run a statistical analysis to obtain a corrected medical fluid temperature based on a temperature of medical fluid detected by the non-invasive fluid temperature sensor and a temperature of ambient air detected by the ambient air temperature sensor.

29. The medical fluid pumping system of claim 22, wherein the ambient air temperature sensor is mounted to an outer surface of the housing.

30. The medical fluid pumping system of claim 29, wherein the non-invasive fluid temperature sensor is mounted to an inner surface of the housing such that the non-invasive fluid temperature sensor is adjacent the portion of tubing when the portion of tubing is disposed in the slot.

31. The medical fluid pumping system of claim 30, wherein the non-invasive fluid temperature sensor is positioned to contact the portion of tubing when the portion of tubing is disposed in the slot.

32. The medical fluid pumping system of claim 22, wherein the non-invasive fluid temperature sensor is positioned in the slot in the housing.

33. The medical fluid pumping system of claim 22, wherein the non-invasive fluid temperature sensor is an infrared temperature sensor.

34. The medical fluid pumping system of claim 22, wherein the fluid circuitry further comprises a drip chamber, a dialyzer system, an air release chamber, and a structural support member.

35. The medical fluid pumping system of claim 34, wherein the non-invasive fluid temperature sensor is positioned downstream of the air release chamber.