Apparatus and method for in-vivo plasmapheresis using periodic backflush containing anticoagulant

• US 20060106331A1
• Filed: 12/29/2005
• Published: 05/18/2006
• Est. Priority Date: 01/04/2001
• Status: Active Grant

• Current Assignee: Transvivo, Inc.
• Original Assignee: Transvivo, Inc.
• Inventors: Peters, Harold W., Cooper, Tommy Gene, Gorsuch, Reynolds G., Handley, Harold H. Jr.
• Granted Patent: US 7,476,210 B2
• Time in Patent Office: Days
• US Class Current: 604/6.90
• CPC Class Codes: A61M 1/3661 for haemodialysis
• CPC Class Codes: A61M 1/3672 Means preventing coagulation
• CPC Class Codes: A61M 2025/0031 characterized by lumina for withdrawing or delivering, i.e. used for extracorporeal circuit treatment
• CPC Class Codes: A61M 2025/0037 characterized by lumina being arranged side-by-side
• CPC Class Codes: A61M 25/0068 Static characteristics of the catheter tip, e.g. shape, atraumatic tip, curved tip or tip structure
• CPC Class Codes: A61M 25/0082 Catheter tip comprising a tool

Abstract

Method for in-vivo plasmapheresis utilizing a plurality of elongated hollow microporous filter fibers periodically interrupt diffusion of blood plasma from a patient, and, for a selected time, directing backflush fluid into the fibers at a pressure and interval sufficient to cleanse the fiber pores, after which plasma diffusion is resumed. The backflush fluid, preferably a normal saline solution, may contain an anticoagulant such as heparin, citrate or NO donor in suitable concentration for systemic anti-coagulation or for treating the fiber for thromboresistance.

Claims

1. A method of carrying out human or animal in-vivo plasmapheresis comprising:

implanting a filter device within a blood vessel of a patient, said filter device comprising a plurality of elongated hollow microporous fibers;

providing a catheter in fluid communication with the hollow interior of said fibers, and diff-using plasma and toxins from the patient'"'"'s blood through the wall of said fibers into the hollow interior thereof; and

periodically interrupting said diffusion of plasma and toxins and backflushing said fibers by directing a backflush fluid containing an amount of anticoagulant at least sufficient to provide fiber thromboresistance through said catheter into said fibers at a pressure and for an interval sufficient to substantially clear the pores of said filter, and after said interval, resuming said diffusion of plasma.

2. A method of claim 1 comprising using a backflush fluid comprising a saline solution containing at least 1 IU heparin per kilogram of human patient body weight.

3. A method of claim 1 comprising using a backflush fluid comprising saline solution containing about 2 or more IU heparin per kilogram of human patient body weight.

4. A method of claim 1 comprising using a backflush fluid comprising saline solution having a heparin concentration of between about 25 IU per ml and about 300 IU per ml.

5. A method of claim 1 comprising using a backflush fluid comprising saline solution having a heparin concentration of between about 75 IU per ml and about 150 IU per ml.

6. A method of claim 1 comprising backflushing at a pressure of between about 15 and about 100 mg Hg for an interval of between about 5 and about 50 seconds.

7. A method of claim 4 wherein heparin concentration is sufficient to provide local anticoagulation and insufficient to provide systemic anticoagulation in a human patient.

8. A method of claim 4 wherein heparin concentration is sufficient to provide systemic anticoagulation in a human patient.

9. A method of claim 1 for inducing systemic anticoagulation comprising using a single bolus of backflush fluid containing between about 50 IU and about 150 IU heparin per kilogram of patient body weight.

10. A method of claim 1 for maintaining systemic anticoagulation comprising using a backflush fluid containing more than about 150 IU heparin per ml and less than about 50 IU per kilogram of patient body weight.

11. A method of claim 1 wherein toxin-containing plasma from said fibers is directed to plasma treatment apparatus through a second lumen of said catheter.

12. A method of claim 11 wherein plasma from plasma treatment apparatus is directed to a third lumen of said catheter and returned to said patient.

13. A method of claim 6 wherein toxin-containing plasma from said fibers is directed to plasma treatment apparatus through a second lumen of said catheter.

14. A method of claim 13 wherein plasma from plasma treatment apparatus is directed to a third lumen of said catheter and returned to said patient.

15. A method of claim 1 wherein said anticoagulant comprises sodium citrate.

16. A method of claim 14 comprising using a backflush fluid comprising a saline solution having a sodium citrate concentration of at least 0.1 mol/liter.

17. A method of claim 16 wherein citrate concentration is sufficient to provide local anticoagulation and insufficient to provide systemic anticoagulation in a human patient.

18. A method of claim 15 wherein sodium citrate concentration is sufficient to provide systemic anticoagulation in a human patient.

19. A method of claim 1 wherein said anticoagulant comprises a NO donor.

20. A method of claim 19 wherein said anticoagulant comprises a NO donor in a concentration sufficient to provide local anticoagulation and insufficient to provide systemic anticoagulation.

21. A method of claim 19 wherein said NO donor comprises a N-nitrosimine, nitrosothiol, organic nitrate, organic nitrite, oximine, sydnonimine, C-nitroso compound, furoxan, benzofuroxan, N-hydroxyguanidine or diazeniumdiolate.

22. A method of claim 1 wherein said backflush fluid contains patient medication.

23. A method of claim 15 wherein said backflush fluid contains patient medication.

24. A method of claim 19 wherein said backflush fluid contains patient medication.

25. A method of carrying out human or animal in-vivo plasmapheresis comprising:

implanting a filter device within a blood vessel of a patient, said filter device comprising one or more elongated hollow tubes and a plurality of elongated microporous fibers capable of separating plasma from whole blood in-vivo, each fiber having an interior lumen extending along the length thereof and having a first and second end secured to one or more of said elongated hollow tubes wherein the interior lumen of each of the fibers communicates with the interior of the one or more hollow tubes;

providing a catheter in fluid communication with the hollow interior of said fibers, and diffusing plasma and toxins from the patient'"'"'s blood through the wall of said fibers into the hollow interior thereof; and

periodically interrupting said diffusion of plasma and toxins and backflushing said fibers by directing a backflush fluid containing an amount of anticoagulant at least sufficient to provide fiber thromboresistance through said catheter into said fibers at a pressure and for an interval sufficient to substantially clear the pores of said filter, and after said interval, resuming said diffusion of plasma.

26. A method of claim 25 wherein said anticoagulant comprises heparin, citrate or NO donor.

27. A method of claim 26 wherein anticoagulant concentration is sufficient to provide local anticoagulation and insufficient to provide systemic anticoagulation in a human patient.

28. A method of carrying out human or animal in-vivo plasmapheresis comprising:

implanting a filter device within a blood vessel of a patient, said filter device comprising one or more elongated hollow tubes and a plurality of elongated microporous fibers having an interior lumen extending along the length thereof, each fiber having a first and second end secured to said one or more elongated hollow tubes, wherein the interior lumen of each of the fibers communicates with the interior of said one or more hollow tubes, and wherein each of the elongated microporous fibers have an asymmetrical fiber wall morphology between the inner wall surface extending along the interior fiber lumen and the outer wall surface, said fiber wall having a higher mass density zone adjacent to the outer wall surface and a lower mass density zone adjacent to the inner wall surface, said higher mass density zone having a smaller average nominal pore size than the average nominal pore size in the lower mass density zone and wherein said fibers are configured to separate plasma from whole blood in-vivo by passing plasma through said fiber wall from the outer wall surface to the inner wall surface and to said interior lumen thereof;

providing a catheter in fluid communication with the hollow interior of said fibers, and diffusing plasma and toxins from the patient'"'"'s blood through the wall of said fibers into the hollow interior thereof; and

periodically interrupting said diffusion of plasma and-toxins and backflushing said fibers by directing a backflush fluid containing an amount of anticoagulant at least sufficient to provide fiber thromboresistance through said catheter into said fibers at a pressure and for an interval sufficient to substantially clear the pores of said filter, and after said interval, resuming said diffusion of plasma.

29. A method of claim 28 wherein said anticoagulant comprises heparin, citrate or NO donor.

30. A method of claim 29 wherein anticoagulant concentration is sufficient to provide local anticoagulation and insufficient to provide systemic anticoagulation in a human patient.