Method for determining platelet inhibitor response

• US 20010021355A1
• Filed: 03/16/2001
• Published: 09/13/2001
• Est. Priority Date: 04/30/1996
• Status: Active Grant

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Baugh, Robert F., Wilson, Adrian C., Lane, Carole G.
• Granted Patent: US 6,555,064 B2
• Time in Patent Office: Days
• US Class Current: 422/73
• CPC Class Codes: G01N 33/4905 Determining clotting time of blood by chemical methods G01N33/86, C12Q1/54
• CPC Class Codes: G01N 33/86 involving blood coagulating time or factors, or their receptors
• CPC Class Codes: Y10T 436/101666 Particle count or volume standard or control [e.g., platelet count standards, etc.]
• CPC Class Codes: Y10T 436/12 Condition responsive control

Abstract

An apparatus is provided for performing an activated clotting time test on a sample of blood containing platelets using a plunger sensor technique, the apparatus comprising a test cell, and wherein the test cell comprises an anticoagulant, a contact activator, and a predetermined amount of a platelet inactivating agent.

Claims

1. An apparatus for performing an activated clotting time test on a sample of blood containing platelets using a plunger sensor technique, said apparatus comprising a test cell, and wherein said test cell comprises an anticoagulant, a contact activator, and a predetermined amount of a platelet inactivating agent.

2. The apparatus of

claim 1

, wherein the anticoagulant is heparin.

3. The apparatus of

claim 2

, wherein the amount of heparin in said cell is between about 1 unit and about 4 units per milliliter of blood sample.

4. The apparatus of

claim 1

, wherein the contact activator is a particle having a negatively charged surface.

5. The apparatus of

claim 3

, wherein said particle is kaolin.

6. The apparatus of

claim 4

, wherein the amount of contact activator in said cell is between about 2 percent and about 15 percent.

7. The apparatus of

claim 4

, wherein said particle is diatomaceous earth.

8. The apparatus of

claim 4

, wherein said particle is powdered glass.

9. The apparatus of

claim 4

, wherein said particle is silica.

10. The apparatus of

claim 1

, wherein said platelet inactivating agent is selected from the group consisting of Abciximab, 4-[4-[4-(aminoiminomethyl)phenyl]-1-piperazinyl]-1-piperidineacetic acid, hydrochloride trihydrate, and acetylsalicylic acid.

11. An apparatus for performing an activated clotting time test on a sample of blood, said apparatus comprising a plurality of test cells, said cells being adapted for receiving an aliquot portion of said sample, wherein each of said cells comprises an anticoagulant and a platelet inactivating agent, and wherein at least one of said cells further comprises a clotting activator, wherein a clotting time is determined for each of said aliquot portions, and wherein a relative clotting time for each of said aliquot portions comprising the clotting activator is determined as compared to a reference clotting time for said at least one cell containing no clotting activator, wherein said relative clotting times in said cells are determinative of the clotting activation of said clotting activator.

12. The apparatus of

claim 11

, wherein the anticoagulant is heparin.

13. The apparatus of

claim 12

, wherein the amount of heparin in said cell is between about 1 unit and about 4 units per milliliter of blood sample.

14. The apparatus of

claim 11

, wherein the contact activator is a particle having a negatively charged surface.

15. The apparatus of

claim 13

, wherein said particle is kaolin.

16. The apparatus of

claim 14

, wherein the amount of contact activator in said cell is between about 2 percent and about 15 percent.

17. The apparatus of

claim 14

, wherein said particle is diatomaceous earth.

18. The apparatus of

claim 14

, wherein said particle is powdered glass.

19. The apparatus of

claim 14

, wherein said particle is silica.

20. The apparatus of

claim 11

, wherein said platelet inactivating agent is selected from the group consisting of Abciximab, 4-[4-[4-(aminoiminomethyl)phenyl]-1-piperazinyl]-1-piperidineacetic acid, hydrochloride trihydrate, and acetylsalicylic acid.