Extracorporeal circuit blood heat exchanger

• US 4,231,425 A
• Filed: 02/27/1978
• Issued: 11/04/1980
• Est. Priority Date: 02/27/1978
• Status: Expired due to Term

• Current Assignee: William R. Engstrom
• Original Assignee: William R. Engstrom
• Inventors: Engstrom, William R.
• Primary Examiner(s): Richter, Sheldon
• Application Number:
  US05/881,392
• Time in Patent Office: 981 Days
• Field of Search: 165/169, 165/46, 165/159, 165/163, 165/154, 165/156, 165/164
• US Class Current: 165/156
• CPC Class Codes: A61M 2205/3606 cooled
• CPC Class Codes: A61M 2205/366 by liquid heat exchangers
• CPC Class Codes: A61M 5/44 having means for cooling or heating the devices or media
• CPC Class Codes: F28D 7/024 the conduits of only one medium being helically coiled tubes, the coils having a cylindrical configuration
• CPC Class Codes: F28D 7/026 the conduits of only one medium being helically coiled and formed by bent members, e.g. plates, the coils having a cylindrical configuration
• CPC Class Codes: F28D 7/106 consisting of two coaxial conduits or modules of two coaxial conduits
• CPC Class Codes: F28F 1/02 Tubular elements of cross-section which is non-circular F28F1/08, F28F1/10 take precedence
• CPC Class Codes: F28F 21/08 of metal
• CPC Class Codes: F28F 9/00 Casings; Header boxes; Auxiliary supports for elements; Auxiliary members within casings

Abstract

A heat exchanger is provided for use in a blood handling system whereby the blood may be selectively heated or cooled, as required by the nature and stage of the operation. The heat exchanger, in the preferred embodiment, is in the form of a cylindrical housing having walls defining a helical path for the flow of blood through the exchanger and about the axis of the housing. The heat exchanging medium, typically water, flows separately through a conduit in the housing, the walls of which at least partially define the helical blood conduit for heating or cooling the blood flowing therethrough. The heat exchanger is characterized by a controlled route for the blood so as to uniformly expose the blood to the same type of heating or cooling and without creating dead spots in the blood flow. A long path of blood flow is provided in a small package with a highly efficient thermal transfer.

Claims

1. A heat exchanger for use in an extracorporeal blood circuit, or the like, comprising

(a) a housing of a clear, transparent material,

(b) said housing including walls forming a portion of a helical passage for the flow of blood therethrough,

(c) a tubular conduit mounted to and passing through said housing for the flow of a heat exchange medium therethrough,

(d) the exterior of said conduit forming another portion of said helical passage whereby blood flowing through said helical passage will be in direct contact with said conduit,

(e) said housing including a cylindrical inner wall and a cylindrical outer wall spaced from the inner wall to define an annular chamber therebetween,

(f) said conduit being in the form of a helix and mounted in said chamber, each convolution of said conduit being in contact with the inner and outer walls and spaced from adjacent convolutions to define said helical passage, and,

(g) blood receiving means disposed within said inner wall and connected to the discharge end of said helical blood passage,

(h) said inner wall being tubular and said outer wall being comprised of a pair of cooperating semi-cylindrical shell sections having end flanges and joined to one another and to said inner wall.

2. A heat exchanger, according to claim 1, wherein the cross-sectional shape and dimension of said passage is substantially constant over the major portion thereof.

3. A heat exchanger, according to claim 1, wherein one shell section is formed with inlet and outlet connections for said helical blood passage and said other shell section is formed with sealed openings through which the ends of said conduit extend.

4. A heat exchanger, according to claim 1, wherein said tubular conduit is circular in cross-section.

5. A heat exchanger, according to claim 1, wherein said tubular conduit is rectangular in cross-section.

6. A heat exchanger, according to claim 1, wherein said tubular conduit is elliptical in cross-section.