Filtration device useable for removal of leukocytes and other blood components

• US 6,015,500 A
• Filed: 07/20/1998
• Issued: 01/18/2000
• Est. Priority Date: 03/10/1994
• Status: Expired due to Term

• Current Assignee: Haemonetics Puerto Rico LLC (Haemonetics Corporation)
• Original Assignee: HemaSure, Inc.
• Inventors: Zuk, Peter Jr.
• Primary Examiner(s): Kim, John
• Application Number:
  US09/119,292
• Time in Patent Office: 547 Days
• Field of Search: 210/97, 210/188, 210/435, 210/436, 210/472, 210/767, 210/800, 210/252, 96/6, 96/155, 95/241
• US Class Current: 210/767
• CPC Class Codes: A61M 1/3627 Degassing devices; Buffer reservoirs; Drip chambers; Blood filters
• CPC Class Codes: A61M 1/3633 Blood component filters, e.g. leukocyte filters
• CPC Class Codes: A61M 1/3643 Priming, rinsing before or after use
• CPC Class Codes: A61M 1/3652 using gas, e.g. air
• CPC Class Codes: A61M 2202/005 residue retained by the filter due to size
• CPC Class Codes: A61M 2202/0439 White blood cells; Leucocytes lymphocytes A61M2202/0407
• CPC Class Codes: A61M 2205/7527 liquophilic, hydrophilic
• CPC Class Codes: A61M 2205/7536 allowing gas passage, but preventing liquid passage, e.g. liquophobic, hydrophobic, water-repellent membranes
• CPC Class Codes: B01D 19/0031 by filtration
• CPC Class Codes: B01D 36/001 Filters in combination with devices for the removal of gas, air purge systems
• CPC Class Codes: B01D 46/0012 In-line filters
• CPC Class Codes: B01D 61/18 Apparatus therefor
• CPC Class Codes: B01D 61/20 Accessories; Auxiliary operations
• CPC Class Codes: B01D 63/08 Flat membrane modules
• CPC Class Codes: B01D 63/087 Single membrane modules

Abstract

A liquid filtration device useable for removing leukocytes from blood contains a first chamber which is in fluid flow relationship with a second chamber. Filtration elements separate the first chamber from the second chamber so that liquid flowing from the first chamber is filtered thereby prior to entry into the second chamber. A passage leads from the second chamber into the first chamber and a hydrophobic filter may be used to prevent liquid from the first chamber from flowing through the passage into the second chamber while allowing air to flow therethrough. An outlet is located in the second chamber, preferably at the bottom thereof. A second outlet may be located within the second chamber and may be placed in fluid flow relationship therewith by a conduit or the like.

Claims

1. A method of processing biological liquid from an enclosed flexible supply bag through a filtration media of a processing system comprising:

flowing biological liquid into an inlet and out of an outlet of said system;

automatically restricting the flow of biological liquid within said system downstream of a port, said port covered with a hydrophobic filter material to allow biological liquid to back up above the level of said port within said system during filtration, said port leading outside of said system and being located downstream of said inlet and upstream of said filtration media;

automatically preventing gas from entering into said processing system through said port by maintaining the level of biological liquid above the port until the flow of biological liquid from said flexible supply bag ceases; and

automatically allowing gas to enter the system through said port when the flow of liquid ceases thereby automatically draining biological liquid within said system.

2. The method of claim 1 wherein the flow of biological liquid is restricted by a narrow cross-sectional area within said processing system.

3. The method of claim 2 wherein said biological liquid is blood or a blood product.

4. The method of claim 3 wherein said filtration media comprises a leukocyte filter media.

5. The method of claim 4 wherein the biological liquid flows into a receiving bag.

6. The method of claim 5 wherein said receiving bag is located at a height below said filtration media and below said port.

7. The method of claim 6 wherein said port is located at a height greater than said leukocyte filter media.

8. A method of filtering leukocytes from blood or a blood product in a sterile system comprising:

flowing blood or blood product into an inlet and out of an outlet into a receiving container of said system;

restricting the flow of blood or blood product downstream of a port and upstream of said receiving container during filtration to prevent external gas from entering into the system through said port and mixing with the blood or blood product, said port leading outside of said system and being covered with a hydrophobic filter media, said port being located downstream of said inlet and upstream or adjacent a leukocyte filter;

flowing blood or blood product through the leukocyte filter, said leukocyte filter being located upstream of said outlet;

automatically allowing gas to enter the system through the port when the flow of blood or blood product ceases to thereby automatically drain blood or blood product remaining within the system.

9. The method of claim 8 wherein the port is positioned upstream of said leukocyte filter.

10. The method of claim 9 wherein the port is located between a blood supply bag and the leukocyte filter.

11. The method of claim 10 wherein the blood or blood product is drained into a collection bag.

12. A method of processing a biological liquid comprising:

flowing biological liquid through an inlet of a processing system, said processing system having a port therein covered with a hydrophobic filter media, said port leading to outside of said system and adapted to keep the system sterile;

restricting the flow of liquid downstream of the port and upstream of an outlet of said processing system while flowing said liquid through the system and through a filtration media so that the pressure head of the liquid in the system at the level of said port is greater than atmospheric pressure, said port being located downstream of said inlet and upstream of said outlet; and

automatically allowing gas to enter the port when the pressure of the liquid in the system at the level of the port becomes less than atmospheric pressure to drain biological liquid remaining within the system into a receiving container.

13. The method of claim 12 wherein the flow of biological liquid is restricted by a narrow cross-sectional area within said processing system.

14. The method of claim 13 wherein said biological liquid is blood or a blood product.

15. The method of claim 14 further comprising filtering leukocytes from the blood or blood product flowing within the system.

16. The method of claim 14 wherein the biological liquid flows into a receiving bag.

17. The method of claim 16 wherein said port is located upstream of said filtration media.

18. The method of claim 17 wherein said receiving bag is located at a height below said filtration media and below said port.

19. A biological liquid filtration system including a receiving container, comprising:

a filtration media within said system adapted to allow biological liquid to flow therethrough for filtration;

a self-contained automatic venting unit, said venting unit comprising an inlet, an outlet and an automatic vent, wherein the outlet is located upstream of the filtration media;

said automatic vent comprising a port covered with a hydrophobic filtration media, said automatic vent being located downstream of said inlet and upstream of said filtration media, said automatic vent leading outside of said system and being adapted to prevent gas from entering said system through said port while the biological liquid flows downstream of said port until the flow of biological liquid ceases and then automatically allow gas to enter the system through said port after the flow of biological liquid ceases and then drain biological liquid from within said system into the receiving container.

20. The system of claim 19 further comprising a narrow cross-sectional area within said system, wherein said narrow cross-sectional area is located downstream of said automatic vent.

21. The system of claim 19 wherein said filtration media comprises a leukocyte filter media.

22. The system of claim 21 further comprising a receiving bag located downstream of said leukocyte filter media.

23. The system of claim 22 wherein said receiving bag is located below said port and said leukocyte filter media.

24. The system of claim 23 wherein said port is located at a height greater than said leukocyte filter media.

25. A method of filtering leukocytes from blood or a blood product within a filtration system comprising:

flowing the blood or blood product from a flexible supply bag through an inlet and through a leukocyte filter wherein an outlet is located downstream of said inlet;

automatically restricting the flow of blood or blood product downstream of the inlet and upstream or adjacent to said leukocyte filter during filtration to prevent external gas from entering the system through a port and mixing with the blood or blood product within the system, said port covered by a hydrophobic filter media and located downstream of said inlet and upstream of said filter; and

automatically allowing gas to enter the port when the flow of blood or blood product ceases, to thereby allow blood or blood product to drain through the leukocyte filter.

26. A method of filtering leukocytes from blood or a blood product comprising:

flowing blood or the blood product into an inlet and out of an outlet of a filtration system;

flowing the blood or blood product through a leukocyte filter of said filtration system;

automatically restricting the flow of blood or blood product downstream of said inlet and upstream of said outlet to prevent external gas from entering the system, during filtration, through a port and mixing with the blood or blood product within the system, said port covered with a hydrophobic filter media and located downstream of said inlet and upstream of said outlet;

allowing gas to automatically enter the port when the flow of blood or blood product ceases, thereby allowing blood or blood product in the system to drain.

27. The method of claim 26 wherein the flow of blood or blood product is restricted by a narrow cross-sectional area.

28. The method of claim 27 wherein the blood or blood product flows into a receiving bag.

29. The method of claim 26 wherein said port is located upstream of said leukocyte filter.

30. The method of claim 26 wherein said port is located at a height greater than said leukocyte filter.

31. A method of processing biological liquid through a filtration media of a processing system comprising:

flowing biological liquid within said system through said filtration media located between an inlet and an outlet of the processing system;

automatically restricting the flow of said biological liquid within said system upstream of said outlet while filtration occurs to cause the pressure of biological liquid at a level of a port covered with a hydrophobic filter media within said system to be greater than atmospheric pressure;

preventing gas from entering into the processing system through said port located upstream of said filtration media and downstream of said inlet by maintaining the pressure of biological liquid at the level of said port above atmospheric pressure; and

automatically allowing gas to enter the system through the port when the pressure of biological liquid within the system at the level of the port is less than atmospheric pressure thereby draining biological liquid within said system through said outlet.

32. The method of claim 31 wherein the flow of biological liquid is restricted by a narrow cross-sectional area within said processing system.

33. The method of claim 32 wherein said biological liquid is blood or a blood product.

34. The method of claim 33 wherein said filtration media comprises a leukocyte filter media.

35. The method of claim 34 wherein the biological liquid flows into a receiving bag.

36. The method of claim 35 wherein said port is located upstream of said leukocyte filter media.

37. The method of claim 36 wherein said receiving bag is at a height below said filter media and below said port.

38. A method of processing a biological liquid comprising:

flowing biological liquid through an inlet of a processing system, said processing system having a port therein covered with a hydrophobic filter media, said port leading to outside of said system and adapted to keep the system sterile;

restricting the flow of liquid downstream of the port and upstream of an outlet of said processing system while flowing said liquid through the system including a narrow-cross sectional area of the system wherein the pressure head of the fluid in the system at the level of said port is greater than atmospheric pressure, said port being located downstream of said inlet and upstream of said outlet; and

automatically allowing gas to enter the port when the pressure of the liquid in the system at the level of the port becomes less than atmospheric pressure to drain biological liquid remaining within the system.

39. The method of claim 38 wherein said biological liquid is blood or a blood product.

40. The method of claim 38 wherein said system includes a filtration media located between the inlet and the outlet.

41. The method of claim 39 wherein said system includes a filtration media located between the inlet and the outlet.

42. The method of claim 41 further comprising filtering leukocytes from the blood or blood product flowing within the system.

43. The method of claim 40 wherein the port is located upstream of said filtration media.

44. The method of claim 40 wherein the biological liquid flows into a receiving bag.

45. The method of claim 44 wherein said receiving bag is located at a height below said filtration media and below said port.

46. A method of processing a biological liquid comprising:

flowing biological liquid through an inlet of a processing system, said processing system having a port therein covered with a hydrophobic filter media, said port leading to outside of said system and adapted to keep the system sterile;

restricting the flow of liquid downstream of the port and upstream of an outlet of said processing system to prevent external gas from entering into the system through said port and mixing with the biological liquid while flowing said liquid through the system and through a filtration media, said port being located downstream of said inlet and upstream of said outlet; and

automatically allowing gas to enter the system through the port when the flow of liquid ceases and thereby draining biological liquid remaining within the system into a receiving container.

47. A method of processing a biological liquid comprising:

flowing biological liquid through an inlet of a processing system, said processing system having a port therein covered with a hydrophobic filter media, said port leading to outside of said system and adapted to keep the system sterile;

restricting the flow of liquid downstream of the port and upstream of an outlet of said processing system to prevent external gas from entering into the system through said port and mixing with the biological liquid while flowing said liquid through the system and through a narrow-cross section area in the system, said port being located downstream of said inlet and upstream of said outlet; and

automatically allowing gas to enter the system through the port when the flow of liquid ceases and thereby draining biological liquid remaining within the system.

48. The method of claim 47 wherein said biological liquid is blood or a blood product.

49. The method of claim 47 wherein said system includes a filtration media located between the inlet and the outlet.

50. The method of claim 48 wherein said system includes a filtration media located between the inlet and the outlet.

51. The method of claim 50 further comprising filtering leukocytes from the blood or blood product flowing within the system.

52. The method of claim 49 wherein the port is located upstream of said filtration media.

53. The method of claim 49 wherein the biological liquid flows into a receiving bag.

54. The method of claim 53 wherein said receiving bag is located at a height below said filtration media and below said port.