Biological fluid warmer

• US 5,101,804 A
• Filed: 09/04/1990
• Issued: 04/07/1992
• Est. Priority Date: 09/04/1990
• Status: Expired due to Fees

• Current Assignee: Baylor College of Medicine (Baylor College)
• Original Assignee: Baylor College of Medicine (Baylor College)
• Inventors: Cohn, William E.
• Primary Examiner(s): Jones, Larry
• Application Number:
  US07/579,003
• Time in Patent Office: 581 Days
• Field of Search: 126/263, 126/204, 126/205, 126/207, 62/4, 604/113, 604/4, 604/408, 128/399, 128/400, 128/898, 128/DIG. 2, 165/104.15, 165/104.17
• US Class Current: 126/263.01
• CPC Class Codes: A61M 2205/364 by chemical reaction
• CPC Class Codes: A61M 5/44 having means for cooling or heating the devices or media
• CPC Class Codes: F24V 30/00 Apparatus or devices using heat produced by exothermal chemical reactions other than combustion

Abstract

The present invention relates to a device and method for warming biological fluids. The portable self-contained device which warms physiological fluids including blood is comprised of a reaction container which is capable of storing at least one chemical which when mixed with a second chemical will produce an exothermic chemical reaction, a mixing means for mixing the two chemicals to produce the exothermic chemical reaction, a heat exchanger to absorb heat from the exothermic reaction and transfer it to the physiological fluid or blood, a temperature regulating means to regulate the maximum temperature of the device and an insulating container for enclosing the reaction means, heat exchanger and temperature regulating means. The method of rapidly heating the stored cold physiological fluids including blood to about 39° during infusion comprise the step of activating the physiological fluid warming device by mixing the chemicals to produce the exothermic chemical reaction and passing the physiological fluid or blood through the heat exchanger.

Claims

1. A portable, self-contained device for warming a physiological fluid comprising:

a reaction container capable of storing at least one chemical, said chemical capable of producing an exothermic chemical reaction when mixed with a second chemical;

a mixing means for mixing the first and second chemicals to produce said exothermic chemical reaction within said reaction container;

a heat exchanger having an inlet and outlet, said heat exchanger sufficiently close to said reaction container to absorb heat from said exothermic reaction and transfer said heat to the physiological fluid;

a temperature regulatory means in contact with said heat exchanger and said reaction container to regulate the maximum temperature of the device; and

an insulating container for enclosing said reaction container, mixing means, heat exchanger and temperature regulatory means, said insulating container having an inlet port and an outlet port, wherein the inlet of the heat exchanger passes through the inlet port and the outlet of the heat exchanger passes through the outlet port.

2. The device of claim 1, wherein said temperature regulating means includes a composition of matter that undergoes a phase change at a temperature of between about 32°

to 39°

C.

3. The composition of matter of claim 2 wherein said matter is selected from the group consisting of waxes, polymers and crystalline solids.

4. The device of claim 1, further comprising a filter attached to one end of the conduit.

5. The device of claim 1 wherein,

the first chemical is selected from the group consisting of anhydrous calcium carbonate, anhydrous calcium chloride, anhydrous calcium oxide, anhydrous sodium hydroxide and other anhydrous soluable salts;

and

the second chemical is water.

6. The device of claim 1, wherein said insulating container is composed of insulating material.

7. The device of claim 1, further comprising a temperature indicator.

8. The device of claim 1, further comprising more than one reaction container.

9. A method of rapidly heating stored cool physiological fluid to about 39°

C. during infusion in a portable, self-contained device, comprising the steps of;

activating the device by mixing in a reaction container first and second chemicals to produce an exothermic chemical reaction; and

passing the physiological fluid through a heat exchanger in said device prior to infusion, wherein said heat exchanger is sufficiently close to said reaction container to absorb heat from said exothermic reaction and transfer said heat to the physiological fluid and wherein a temperature regulatory means is in contact with said heat exchanger and said reaction container to regulate the temperature of the device.

10. The method of claim 9, wherein said physiological fluid is blood.

11. A portable self-contained device for warming blood comprising:

a reaction container capable of storing separately at least a pair of chemicals, said chemicals producing an exothermic chemical reaction when mixed;

a mixing means integral with said reaction container for mixing at least a pair of chemicals;

a conduit having an inlet and an outlet said conduit coiled around said reaction container;

a temperature regulating means having a phase change reaction temperature of between 34°

to 39°

C., said temperature regulating means coating said reaction container and said conduit and forming a layer between said reaction container and said conduit;

an insulating container enclosing the reaction container, at least a pair of chemicals, the conduit, the mixing means and the temperature regulation means, said insulating container having inlet and outlet ports, wherein one open end of said conduit passes through the inlet port, and the other end of said conduit passes through the outlet port.

12. The device of claim 11, wherein said temperature regulating means is selected from the group consisting of waxes, polymers and crystalline solids.

13. The device of claim 11, further comprising a temperature indicator.

14. The device of claim 11, further comprising more than one reaction container.

15. The device of claim 11, further comprising, a filter for filtering the blood, wherein said filter is attached to one end of the conduit.

16. A method of rapidly heating stored cooled blood up to about 37°

C. prior to infusion in a portable self-contained device, comprising the steps of;

activating the device by mixing at least a pair of chemicals in the device between a conduit and reaction container to produce an exothermic chemical reaction; and

passing the blood through the conduit in said device, wherein there is a temperature regulating means having a phase change reaction temperature of between 34°

to 39°

C., said temperature regulating means coating said conduit and transferring heat from the exothermic reaction to the blood.

17. A device for warming physiological fluids comprising:

a first container enclosing a first reactant wherein said first reactant produces an exothermic chemical reaction when contacted with a second reactant said first container composed of friable material;

a second container having an inlet port and outlet port and enclosing said first container and containing said second reactant;

a conduit having an opening at each end positioned within said second container and extending therethrough, said conduit communicating with the exterior of said fluid warming apparatus through the inlet port and outlet port of said second container.

18. The apparatus of claim 17 wherein said conduit is coiled about a longitudinal axis of the second container.

19. The apparatus of claim 17 wherein said second container and said conduit are composed of flexible material.

20. The apparatus of claim 17 having a plurality of first containers.