Method and device for monitoring platelet function

• US 7,534,620 B2
• Filed: 12/07/2007
• Issued: 05/19/2009
• Est. Priority Date: 09/10/2002
• Status: Active Grant

• Current Assignee: PlaCor, Inc.
• Original Assignee: PlaCor, Inc.
• Inventors: Ericson, Daniel G.
• Primary Examiner(s): WALLENHORST, MAUREEN
• Application Number:
  US11/952,328
• Publication Number:
  US 20080086045A1
• Time in Patent Office: 529 Days
• Field of Search: 436/52, 436/63, 436/69, 436/148, 436/164, 436/165, 436/180, 422/68.1, 422/73, 422/81, 422/82.05, 422/82.09, 422/82.13, 435/2, 435/13, 435/287.1
• US Class Current: 436/69
• CPC Class Codes: G01N 33/4905 Determining clotting time of blood by chemical methods G01N33/86, C12Q1/54

Abstract

The invention provides a method of monitoring platelet function in a mammal by passing blood removed from the body of the mammal through a passageway to contact an obstruction or irregularity in the passageway to generate a platelet mass in the passageway, and monitoring the flow or composition of the blood in the passageway to detect the platelet mass. The flow and composition change in response to the formation of a platelet mass in the passageway. Devices, articles, and kits for performing the methods are also disclosed.

Claims

1. A method for monitoring the flow or composition of blood comprising:

passing whole blood removed from a mammal through a passageway comprising an obstruction in the passageway and a narrowing of the passageway;

contacting the blood with the obstruction and the narrowing; and

monitoring the flow or composition of the blood in the passageway,

wherein the blood passes bidirectionally through the passageway; and

wherein less than 2 ml of blood is removed from the body of the mammal.

2. The method of claim 1, wherein less than 1 ml of blood is removed from the body of the mammal.

3. The method of claim 1, wherein less than 0.4 ml of blood is removed from the body of the mammal.

4. The method of claim 1, wherein less than 0.2 ml of blood is removed from the body of the mammal.

5. The method of claim 1, wherein less than 0.1 ml of blood is removed from the body of the mammal.

6. The method of claim 1, wherein less than 50 μ

l of blood is removed from the body of the mammal.

7. The method of claim 6, wherein the blood is removed from the body of the mammal by a finger prick.

8. The method of claim 1, wherein a single drop of blood is removed from the body of the mammal.

9. The method of claim 8, wherein the blood is removed from the body of the mammal by a finger prick.

10. The method of claim 1, wherein the flow of the blood in the passageway is monitored.

11. The method of claim 10, wherein the flow is monitored by monitoring the pressure of the blood in the passageway.

12. The method of claim 11, wherein the pressure is monitored with a pressure transducer.

13. The method of claim 10, wherein the flow is monitored optically.

14. The method of claim 13, wherein the flow is monitored with a light-emitting diode and a light detector.

15. The method of claim 1, wherein the composition of the blood in the passageway is monitored.

16. The method of claim 15, wherein the size of a platelet mass is directly monitored.

17. The method of claim 15, wherein the chemical composition of the blood is monitored.

18. The method of claim 17, wherein at least one of the pH, concentration of O₂, concentration of CO₂ concentration of Mg⁺⁺, or concentration of K⁺ is monitored.

19. The method of claim 1, wherein the obstruction is one or more plugs that partially obstruct the passageway.

20. The method of claim 1, wherein no biological or chemical agents are added to the removed blood.

21. The method of claim 1, wherein the passageway and blood do not comprise an added anti-coagulant.

22. The method of claim 1, wherein the obstruction is a wire.

23. The method of claim 1, wherein the obstruction is a filter.

24. The method of claim 1, wherein the obstruction is a mesh.

25. The method of claim 1, wherein the obstruction is a fiber.

26. The method of claim 1, wherein the obstruction is a filter membrane.

27. The method of claim 1, wherein the obstruction is a plurality of fibers.

28. The method of claim 1, wherein the obstruction is a plurality of wires.

29. The method of claim 1, wherein the obstruction is a plurality of ribbons.

30. The method of claim 1, wherein the obstruction is a piece of woven or knitted fabric.

31. A device for monitoring the flow or composition of blood comprising:

a fluid-tight material forming a passageway comprising an obstruction in the passageway and a narrowing of the passageway;

a pump functionally linked to the passageway for pumping blood through the passageway; and

a detector for detecting the flow or composition of blood in the passageway,

wherein the obstruction and the narrowing are arranged such that when blood is pumped through the passageway, the blood contacts the obstruction and the narrowing.

32. The device of claim 31, wherein the detector detects the flow of blood in the passageway.

33. The device of claim 32, wherein the flow of blood in the passageway is detected by monitoring the pressure of the blood in the passageway.

34. The device of claim 33, wherein the device further comprises a pressure transducer.

35. The device of claim 31, wherein the detector detects the composition of blood in the passageway.

36. The device of claim 35, wherein the composition of blood in the passageway is detected by monitoring at least one of the pH, concentration of O₂, concentration of CO₂, concentration of Mg⁺⁺, or concentration of K⁺.

37. The device of claim 31, wherein the pump is capable of pumping blood through the passageway bidirectionally.

38. The device of claim 31, wherein the obstruction and the narrowing are arranged such that when blood is pumped through the passageway, the blood contacts the obstruction and the narrowing and generates a platelet mass in the passageway.

39. The device of claim 38, wherein the platelet mass is substantially depleted in fibrin in comparison to a natural clot.

40. The device of claim 31, wherein the passageway has a volume of less than 2 ml.

41. The device of claim 31, wherein the passageway has a volume of less than 1 ml.

42. The device of claim 31, wherein the passageway has a volume of less than 0.4 ml.

43. The device of claim 31, wherein the passageway has a volume of less than 0.2 ml.

44. The device of claim 31, wherein the passageway has a volume of less than 0.1 ml.

45. The device of claim 31, wherein the passageway has a volume of less than 50 μ

l ml.

46. The device of claim 31, wherein the obstruction is one or more plugs that partially obstruct the passageway.

47. The device of claim 31, wherein the obstruction is a wire.

48. The device of claim 31, wherein the obstruction is a filter.

49. The device of claim 31, wherein the obstruction is a mesh.

50. The device of claim 31, wherein the obstruction is a fiber.

51. The device of claim 31, wherein the obstruction is a filter membrane.

52. The device of claim 31, wherein the obstruction is a plurality of fibers.

53. The device of claim 31, wherein the obstruction is a plurality of wires.

54. The device of claim 31, wherein the obstruction is a plurality of ribbons.

55. The device of claim 31, wherein the obstruction is a piece of woven or knitted fabric.

56. The device of claim 31, wherein the device operates without a biological or chemical agent that activates platelets.

57. The device of claim 31, wherein the device operates without an anti-coagulant.