Method and device for monitoring platelet function

• US 20050196748A1
• Filed: 03/10/2005
• Published: 09/08/2005
• Est. Priority Date: 09/10/2002
• Status: Active Grant

• Current Assignee: PlaCor, Inc.
• Original Assignee: PlaCor, Inc.
• Inventors: Ericson, Daniel G.
• Granted Patent: US 7,309,607 B2
• Time in Patent Office: Days
• US Class Current: 435/4
• CPC Class Codes: G01N 33/4905 Determining clotting time of blood by chemical methods G01N33/86, C12Q1/56

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 of monitoring platelet function comprising:

passing blood removed from a mammal through a passageway comprising an obstruction or an irregularity, to contact the obstruction or the wall of the passageway at the irregularity, to generate a platelet mass in the passageway; and

monitoring the flow or composition of the blood in the passageway to detect formation of the platelet mass;

wherein the passageway does not comprise an added biological agent that activates platelets.

2. The method of claim 1 wherein the blood passes the obstruction or irregularity.

3. The method of claim 1 or wherein the blood does not comprise an added biological agent that activates platelets.

4. The method of claim 1 wherein the passageway and blood do not comprise an added chemical agent that activates platelets.

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

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

9. The method of claim 8 wherein the flow is monitored by monitoring the pressure of the blood in the passageway.

10. The method of claim 9 wherein the pressure is monitored with a pressure transducer.

11. The method of claim 8 wherein the flow is monitored optically.

12. The method of claim 11 wherein the flow is monitored with a light-emitting diode and a light detector.

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

14. The method of claim 13 wherein the size of the platelet mass is directly monitored.

15. The method of claim 13 wherein the chemical composition of the blood is monitored.

16. The method of claim 15 wherein the pH, concentration of O₂, concentration of CO₂, concentration of Mg⁺⁺, or concentration of K⁺ is monitored.

17. The method of claim 1 wherein the passageway comprises an obstruction.

18. The method of claim 17 wherein the obstruction is a plug.

19. The method of claim 18 wherein the plug partially obstructs the passageway.

20. The method of claim 18 wherein the plug fully obstructs the passageway.

21. The method of claim 18 wherein the plug is a wire.

22. The method of claim 1 wherein the platelet mass has a thickness in all dimensions of at least about 20 microns.

23. The method of claim 1 wherein the platelets are activated at least partially by mechanical forces.

24. The method of claim 23 wherein the platelets are activated solely by mechanical forces.

25. The method of claim 1 wherein the platelet mass is substantially depleted in red blood cells and white blood cells in comparison to a natural clot.

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

37. The method of claim 1 wherein the blood passes bidirectionally through the passageway.

38. The method of claim 1 wherein at least part of the passageway is a loop, wherein the blood passes unidirectionally through the loop.

39. The method of claim 1 wherein the blood is whole blood.

40. The method of claim 1 wherein the blood is fractionated blood.

41. The method of claim 1 wherein the mammal is treated with an anti-platelet agent.

42. The method of claim 41 wherein the anti-platelet agent comprises a cyclooxygenase inhibitor, an ADP inhibitor, a GPIIbIIIa inhibitor, or a combination thereof.

6. A method of monitoring platelet function in a mammal comprising:

passing blood removed from a mammal through a passageway comprising an obstruction or an irregularity, to contact the obstruction or the wall of the passageway at the irregularity, to generate a platelet mass in the passageway, and

monitoring the flow or composition of the blood in the passageway to detect formation of the platelet mass;

wherein the platelet mass is substantially depleted in fibrin in comparison to a natural clot.

7. The method of claim 6 wherein the blood passes the obstruction or irregularity.

26. The method of claim 6 wherein the passageway does not comprise an added biological agent that activates platelets.

27. The method of claim 6 wherein the blood does not comprise an added biological agent that activates platelets.

28. The method of claim 6 wherein the passageway and blood do not comprise an added chemical agent that activates platelets.

29. The method of claim 6 wherein no biological or chemical agents are added to the removed blood.

30. The method of claim 6 wherein the passageway does not comprise a biological component to which platelets naturally adhere.

31. The method of claim 6 wherein the passageway does not comprise collagen, ADP, epinephrine, or a derivative thereof.

32. The method of claim 6 wherein the passageway and blood do not comprise an added anti-coagulant.

33. The method of claim 6 further comprising adding a platelet activator to the blood.

34. The method of claim 6 wherein the passageway comprises a platelet activator.

35. The method of claim 33 wherein the platelet activator is thromboxane A₂.

43. A device for monitoring platelet function, comprising:

a fluid-tight material forming a passageway;

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

an obstruction within the passageway, arranged such that when blood is pumped through the passageway to contact the obstruction, a platelet mass substantially free of fibrin forms on or near the obstruction; and

a means for detecting the flow of blood through the passageway to detect formation of the platelet mass.

45. The device of claim 43 wherein the obstruction is arranged such that when blood is pumped through the passageway, the blood passes the obstruction.

49. The device of claim 43 wherein the device operates without a biological agent that activates platelets.

50. The device of claim 43 wherein the device operates without a chemical agent that activates platelets.

44. A device for monitoring platelet function, comprising:

a fluid-tight material forming a passageway;

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

an obstruction within the passageway, arranged such that when blood is pumped through the passageway to contact the obstruction, a platelet mass substantially free of fibrin forms on or near the obstruction; and

a means for detecting the composition of blood in the passageway to detect formation of the platelet mass.

46. A device for monitoring platelet function, comprising:

a fluid-tight material forming a passageway;

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

wherein the passageway comprises an irregularity arranged such that when blood is pumped through the passageway to contact the wall of the passageway at the irregularity, a platelet mass substantially free of fibrin forms on the wall of the passageway at or near the irregularity; and

a means for detecting the flow of blood through the passageway to detect formation of the platelet mass.

48. The device of claim 46 wherein the irregularity is arranged such that when blood is pumped through the passageway, the blood passes the irregularity.

47. A device for monitoring platelet function, comprising:

a fluid-tight material forming a passageway;

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

wherein the passageway comprises an irregularity arranged such that when blood is pumped through the passageway to contact the wall of the passageway at the irregularity, a platelet mass substantially free of fibrin forms on the wall of the passageway at or near the irregularity; and

a means for detecting the composition of blood in the passageway to detect formation of the platelet mass.

51-62. -62. (canceled)