Portable test apparatus and associated method of performing a blood coagulation test

• US 5,534,226 A
• Filed: 04/19/1995
• Issued: 07/09/1996
• Est. Priority Date: 10/21/1994
• Status: Expired due to Term

• Current Assignee: International Technidyne Corporation (Sphingotec GMBH)
• Original Assignee: International Technidyne Corporation (Sphingotec GMBH)
• Inventors: Huang, Ming, Mawhirt, James A., Gavin, Michael, Cimini, Catherine M., Kuklo, Anthony Jr., Marcelino, Eduardo
• Primary Examiner(s): Warden, Jill
• Assistant Examiner(s): CARRILLO, BIBI SHARIDAN
• Application Number:
  US08/424,063
• Time in Patent Office: 447 Days
• Field of Search: 422/73, 436/69, 436/165, 435/13, 128/760, 128/763, 128/765, 606/181
• 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 436/10 Composition for standardization, calibration, simulation, stabilization, preparation or preservation; processes of use in preparation for chemical testing

Abstract

A portable device for performing coagulation tests on a patient'"'"'s blood. Blood is first drawn from a patient using a lancet. The blood is then supplied to a disposable cuvette placed within the testing device. The blood is drawn into multiple conduits within the cuvette. Each of the conduits contains a dried or lyophilized activation reagent that is rehydrated by the blood. The blood in each of the conduits is then reciprocally moved across a restricted region until a predetermined device of coagulation occurs. Since the coagulation time is being monitored in multiple conduits, a representation coagulation time for a given sample can be determined. In at least one of the conduits a normalizing control agent is present. The normalizing consol agent counteracts any effects of anticoagulants present in the blood sample, thereby allowing the blood sample to have generally normal coagulation characteristics. The normalized blood is tested simultaneously with the untreated blood to provide a reference value against which the functionality of the test system and the quality of the sample can be judged.

Claims

1. An apparatus for a blood sample that contains an anticoagulant, comprising:

a disposable cuvette comprising;

a) a plurality of conduits, that include at least one test conduit and at least one control conduit, disposed within said cuvette, each of said plurality of conduits extending from a distal end to a proximal end, wherein each of said plurality of conduits contains at least one restricted region in between said distal end and said proximal end;

b) means for introducing a predetermined volume of the blood into each of said plurality of conduits;

c) a normalizing agent disposed within said at least one control conduit, wherein said normalizing agent is capable of counteracting effects of the anticoagulant in the blood being tested thereby creating a normalized blood sample; and

a test device that includes;

a) a receptacle for receiving said disposable cuvette within said test device;

b) means for reciprocally moving said predetermined volume of the sample back and forth in each of said plurality of conduits through said restricted region between a plurality of zones;

c) detecting means for detecting the presence of said predetermined volume of the blood within each of said plurality of conduits in each of said plurality of zones;

d) means, coupled to said detecting means, for determining an elapsed time to when a predetermined degree of coagulation has occurred in each of said plurality of conduits, thereby providing a test coagulation time for each said test conduit and providing a control coagulation time for each said control conduit, and

e) quantifying means for quantifying said test coagulation time with said control coagulation time to produce a quantified coagulation time result for the blood being tested.

2. The apparatus according to claim 1, wherein said normalizing agent includes Vitamin K dependent clotting factor concentrates, and barium citrate eluate.

3. The apparatus according to claim 2, wherein said normalizing agent further includes gluconic acid, trehalose, malto dextrin and barbital buffered saline.

4. The apparatus according to claim 1, wherein each of said conduits have a prothrombin time reagent disposed therein that mixes with said predetermined volume of blood in each of said conduits.

5. The apparatus according to claim 4, wherein said prothrombin time reagent is disposed in each of said conduits on the side of said restricted region proximate said distal end.

6. The apparatus according to claim 4, wherein said prothrombin time reagent is selected from a group comprising thromboplastin extract and tissue factor.

7. The apparatus according to claim 3, wherein said normalizing agent includes between 1.0 u/m and 3.5 u/ml of Vitamin K dependent clotting factor concentrates, 0.009 u/ml and 0.035 u/ml of barium citrate eluate, 0.008M and 0.03M of gluconic acid, 3.0% and 8.0% trehalose, and 2% and 6% malto dextrin.

8. The apparatus according to claim 1, wherein said test device further includes a heating means for heating said cuvette to a predetermined temperature.

9. The apparatus according to claim 1, wherein said restricted region in each of said conduits has a textured surface to promote blood coagulation thereon.

10. The apparatus according to claim 1, wherein said cuvette further comprises:

a generally transparent member having a plurality of conduits contained therein; and

a channel, common to all of said plurality of conduits through which a predetermined volume of the sample can be drawn into each of said plurality of conduits.

11. An apparatus for testing blood, comprising:

a disposable cuvette that includes;

a) a plurality of conduits, comprising at least one test conduit and at least one control conduit, disposed within said cuvette, each of said plurality of conduits extending from a distal end to a proximal end, wherein each of said plurality of conduits contains at least one restricted region in between said distal end and said proximal end;

b) means for introducing a predetermined volume of the blood into each of said plurality of conduits;

c) an anticoagulant disposed within said at least one control conduit, wherein said anticoagulant is capable of a desired coagulation characteristic in the blood being tested thereby producing a blood control sample having abnormal clotting characteristics; and

a test device that includes;

a) a receptacle for receiving said disposable cuvette within said test device;

b) means for reciprocally moving said predetermined volume of the sample back and forth in each of said plurality of conduits through said restricted region between a plurality of zones;

c) detecting means for detecting the presence of said predetermined volume of the blood within each of said plurality of conduits in each of said plurality of zones;

d) means, coupled to said detecting means, for determining an elapsed time to when a predetermined degree of coagulation has occurred in each of said plurality of conduits, thereby providing a test coagulation time to produce a quantified coagulation time result for the blood being tested for each said test conduit and providing a control coagulation time for each said control conduit; and

e) quantifying means for quantifying said test coagulation time with said control coagulation time to produce a quantified coagulation time result for the blood being tested.

12. The apparatus according to claim 11, wherein each of said conduits have a prothrombin time reagent disposed therein that mixes with said predetermined volume of blood in each of said conduits.

13. The apparatus according to claim 12, wherein said prothrombin time reagent is disposed in each of said conduits on the side of said restricted region proximate said distal end.

14. The apparatus according to claim 12, wherein said prothrombin time reagent is selected from a group comprising thromboplastin extract and tissue factor.

15. The apparatus according to claim 11, wherein said anticoagulant includes heparin.

16. The apparatus according to claim 11, wherein said test device further includes a heating means for heating said cuvette to a predetermined temperature.

17. The apparatus according to claim 11, wherein said restricted region in each of said conduits has a textured surface to promote blood coagulation thereon.