Dialysis fluid heating systems

• US 8,803,044 B2
• Filed: 07/05/2007
• Issued: 08/12/2014
• Est. Priority Date: 11/05/2003
• Status: Active Grant

• Current Assignee: Baxter Healthcare SA (Baxter International Inc.), Baxter International Inc.
• Original Assignee: Baxter Healthcare SA (Baxter International Inc.), Baxter International Inc.
• Inventors: Kienman, Richard E., Roush, Dan, Steck, John E., Slepicka, James S., Yardimci, Atif M., Hecht, Gideon, Busby, Donald D., Chan, William, Ding, Yuanpang S., Reitz, Douglas W., Lauman, Brian C., Lindsay, Jennifer S., Bobart, George F., Twining, Amy L., Kopychev, Andrey, Ozer, Mehmet B.
• Primary Examiner(s): Yuen, Henry
• Assistant Examiner(s): Wasaff, John
• Application Number:
  US11/773,903
• Publication Number:
  US 20080021377A1
• Time in Patent Office: 2,595 Days
• Field of Search: 219/607, 219/628, 219/629, 219/630, 604/29
• US Class Current: 219/607
• CPC Class Codes: A61M 1/1524 the interface providing means for actuating on functional elements of the cassette, e.g. plungers
• CPC Class Codes: A61M 1/153 the cassette being adapted for heating or cooling the treating fluid, e.g. the dialysate or the treating gas
• CPC Class Codes: A61M 1/155 with treatment-fluid pumping means or components thereof
• CPC Class Codes: A61M 1/1561 at least one cassette surface or portion thereof being flexible, e.g. the cassette having a rigid base portion with preformed channels and being covered with a foil
• CPC Class Codes: A61M 1/1565 Details of valves
• CPC Class Codes: A61M 1/1635 with volume chamber balancing devices between used and fresh dialysis fluid
• CPC Class Codes: A61M 1/1696 with dialysate regeneration
• CPC Class Codes: A61M 1/342 Adding solutions to the blood, e.g. substitution solutions for preventing coagulation A61M1/3672
• CPC Class Codes: A61M 1/3434 with pre-dilution and post-dilution
• CPC Class Codes: A61M 1/3437 downstream of the filter, e.g. post-dilution with filtrate
• CPC Class Codes: A61M 1/3458 having electrolytes not present in the dialysate
• CPC Class Codes: A61M 2205/127 with provisions for heating or cooling
• CPC Class Codes: A61M 5/44 having means for cooling or heating the devices or media

Abstract

A dialysis fluid heating system includes a plurality of conductive tubes; first and second end caps located at first and second ends of the tubes, respectively, the first end cap including a dialysis fluid inlet and a dialysis fluid outlet, the end caps and the tubes configured such that dialysis fluid can flow from the fluid inlet of the first end cap, through at least one first tube to the second end cap, and through at least one second tube back to the first end cap; a conductive wire wound around an outside of the conductive tubes; and electronics configured to supply power to the conductive wire, the wire forming a primary coil of a transformer, the tubes forming a secondary coil of the transformer.

Claims

1. A dialysis fluid heating system comprising:

a plurality of conductive tubes;

first and second end caps located at first and second ends of the tubes, respectively, the first end cap including a dialysis fluid inlet and a dialysis fluid outlet, the end caps and the plurality of conductive tubes configured such that dialysis fluid can flow from the fluid inlet of the first end cap, through at least one first tube of the plurality of conductive tubes to the second end cap, and through at least one second tube of the plurality of conductive tubes back to the first end cap;

a conductive wire wound around an outside of each of the plurality of conductive tubes along at least a portion of a length of the plurality of conductive tubes extending between the first and second end caps; and

electronics configured to supply power to the conductive wire, the wire forming a primary coil of a transformer, the plurality of conductive tubes forming a secondary coil of the transformer.

2. The dialysis fluid heating system of claim 1, wherein the conductive wire is at least one of:

(i) wound to form a coil having an axis that is generally parallel with an axis of the conductive tubes;

(ii) wound to form a coil extending past one or both ends of the plurality of conductive tubes;

(iii) wound to form a tight coil with at least substantially no space between windings;

(iv) wound to form a coil with at least one gap between a pair windings; and

(v) at least partially surrounded by a magnetic core.

3. The dialysis fluid heating system of claim 1, the first end cap further configured such that the dialysis fluid flows to the fluid outlet after flowing through the at least one second tube of the plurality of conductive tubes to the first cap.

4. The dialysis fluid heating system of claim 1, the first and second end caps further configured such that fluid flows (i) through at least one third tube of the plurality of conductive tubes from the first end cap to the second end cap after flowing through the at least one second tube of the plurality of conductive tubes, and (ii) through at least one fourth tube of the plurality of conductive tubes to the first end cap.

5. The dialysis fluid heating system of claim 4, wherein at least one of the first and second end caps defines at least one of (i) a diagonal path relative to a side of the at least one of the first and second end caps and (ii) a parallel path relative to a side of the at least one of the first and second end caps, the at least one path extending within the at least one of the first and second end caps from one of the conductive tubes to another of the conductive tubes.

6. The dialysis fluid heating system of claim 1, which includes at least one of:

(i) a static mixer located inside at least one of the tubes and (ii) a temperature sensor positioned to measure a temperature of an outside of one of the conductive tubes.

7. The dialysis fluid heating system of claim 1, wherein a number of the conductive tubes is optimized with a temperature to which the conductive tubes are heated and with a size of the conductive tubes.

8. The dialysis fluid heating system of claim 1, which includes an insulating jacket placed between the conductive wire and the plurality of conductive tubes.

9. The dialysis fluid heating system of claim 8, wherein the conductive wire and the insulating jacket are part of a dialysis instrument, and the conductive tubes and end caps are part of a dialysis disposable operable with the dialysis instrument.

10. The dialysis fluid heating system of claim 1, wherein the first end cap is connected to a disposable pumping cassette.

11. The dialysis fluid heating system of claim 10, wherein the disposable pumping cassette includes first and second collar reinforced tubing ports connected via first and second tubes of the plurality of conductive tubes to the fluid inlet and the fluid outlet of the first end cap.

12. The dialysis fluid heating system of claim 1, wherein at least one of:

(i) the tubes are stainless steel;

(ii) the tubes have magnetic susceptibility;

(iii) the tubes are chamfered at at least one end;

(iv) the tubes are at least substantially round;

(v) the tubes are at least substantially square;

(vi) the tubes are formed from at least one tube having a divider wall;

(vii) the wire is multi-stranded;

(viii) the end caps are electrically insulating; and

(iv) the electronics are configured to supply high frequency alternating current power to the conductive wire.

13. A dialysis fluid heating system comprising:

a plurality of conductive tubes;

first and second end caps located at first and second ends of the tubes, the first end cap including a dialysis fluid inlet, the second end cap including a dialysis fluid outlet, the end caps and the plurality of conductive tubes configured such that the dialysis fluid can flow from the fluid inlet of the first end cap, through at least one first tube of the plurality of conductive tubes to the second end cap, through at least one second tube of the plurality of conductive tubes back to the first end cap, and through at least one third tube of the plurality of conductive tubes back to the second end cap;

a conductive wire wound around an outside of each of the plurality of conductive tubes along at least a portion of a length of the plurality of conductive tubes extending between the first and second end caps; and

electronics configured to supply power to the conductive wire, the wire forming a primary coil of a transformer, the plurality of conductive tubes forming a secondary coil of the transformer.

14. The dialysis fluid heating system of claim 13, the first end cap further configured such that the dialysis fluid flows to the fluid outlet after flowing through the at least one third tube of the plurality of tubes to the second end cap.

15. The dialysis fluid heating system of claim 13, the first and second end caps further configured such that fluid flows (i) through at least one fourth tube of the plurality of conductive tubes from the second end cap to the first end cap after flowing through the at least one third tube of the plurality of conductive tubes, and (ii) through at least one fifth tube of the plurality of conductive tubes to the second end cap.

16. The dialysis fluid heating system of claim 13, wherein at least one of:

(i) a static mixer is located inside at least one of the tubes;

(ii) the first end cap is connected to a disposable pumping cassette;

(iii) the conductive wire is wound to form a coil extending past one or both ends of the plurality of conductive tubes;

(iv) the conductive wire is wound to form a tight coil with at least substantially no space between windings;

(v) the conductive wire is wound to form a coil with at least one gap between a pair windings;

(vi) the end caps are electrically insulating;

(viii) the wire is at least partially surrounded by a magnetic core; and

(ix) the electronics are configured to supply high frequency alternating current power to the conductive wire.

17. The dialysis fluid heating system of claim 16, wherein the disposable pumping cassette includes first and second collar reinforced tubing ports connected via first and second tubes to the fluid inlet and the fluid outlet, respectively.

18. A dialysis fluid heating system comprising:

a tube;

an end cap located at a first end of the tube, the end cap including a dialysis fluid inlet and a dialysis fluid outlet;

a strip of twisted plastic or metal extending into the tube, the strip configured such that the dialysis fluid is urged to flow from the fluid inlet to a second end of the tube and back to the dialysis fluid outlet;

a conductive wire wound around an outside of the tube along at least a portion of a length of the tube extending between the first end of the tube and the second end of the tube; and

electronics configured to supply power to the conductive wire, the wire forming a primary coil of a transformer, at least one of the tube and the strip being conductive and forming a secondary coil of the transformer.

19. The dialysis fluid heating system of claim 18, wherein the strip of twisted plastic or metal includes first and second surfaces structured and arranged such that the dialysis fluid is urged to flow from the fluid inlet along the first surface to the second end of the tube, and then along the second surface back to the dialysis fluid outlet.

20. The dialysis fluid heating system of claim 19, wherein the strip is a strip of twisted metal, which is at least one of:

(i) connected to the end cap;

(ii) stainless steel;

(iii) magnetically susceptible;

(iv) roughened; and

(iv) sintered.