US4782026A
Expired / Lapsed
US
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Collection medium for whole blood
Assignee: Medtronic Electromedics Inc
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Filing: 1985-02-25
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Granted: 1988-11-01
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Expires: 2005-02-25
Abstract
Abstract An inhibitor of Platelet Factor 3 activity is included in a collection medium into which a whole blood sample is a collected. The inhibitor of Platelet Factor 3 activity, it has been discovered, prevents an initial drop in the activated clotting time measured during an assay test conducted on the whole blood sample collected in the medium. The discovery of the problem of the initial drop in the activated clotting time and the solution of including the inhibitor of Platelet Factor 3 activity is of considerable importance in heparin therapy, since the initial drop in the activated clotting time of heparinized blood is substantial. The inhibitor of Platelet Factor 3 activity can be included with a calcium chelating agent in the collection medium. Prostacylin and imidazole, which is an inhibitor of platelet thromboxane A2 synthesis, are effective inhibitors of Platelet Factor 3 activity.
Inventors
- 👤 Robert F. Baugh
- 👤 Cynthia A. Taylor
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 02:43
CPC Classifications
C; C12; C12Q; C12Q1/00; C12Q1/56; Y; Y10; Y10T; Y10T436/00; Y10T436/10; Y10T436/108331
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
101 words
A method of preventing an initial drop in the activated clotting time measured in a recalcified activated clotting time test performed on citrated whole blood collected from a patient, the initial drop otherwise normally occurring and substantially concluding within approximately thirty minutes after drawing the blood from the patient as a result of a platelet-related procoagulant activity initiated by drawing the blood, the method comprising: collecting a sample of the whole blood in citrate, and approximately simultaneously mixing an inhibitor of the initial drop with the blood sample, the inhibitor comprising one of a group consisting of a prostacyclin or imidazole.
Claim 2
Independent Claim
101 words
A method of preventing an initial drop in the activated clotting time measured in a recalcified activated clotting time test performed on citrated whole blood collected from a patient, the initial drop otherwise normally occurring and substantially concluding within approximately thirty minutes after drawing the blood from the patient as a result of a platelet-related procoagulant activity initiated by drawing the blood, the method comprising: collecting a sample of the whole blood in citrate, and approximately simultaneously mixing an inhibitor of the initial drop with the blood sample, the inhibitor comprising one of a group consisting of a prostacyclin or imidazole.
Claim 3
Dependent Claim
38 words
A method as defined in claim 1 wherein: the citrate is approximately a 3.8% sodium citrate concentration, the inhibitor is prostacyclin, and the prostacyclin is present in the approximate amount of 10 nanograms per milliliter of blood collected.
Claim 4
Dependent Claim
36 words
A method as defined in claim 1 wherein: the citrate is approximately a 3.8% sodium citrate concentration, the inhibitor is imidazole, and the imidazole is present in an approximate concentration of 50 mM in the citrate.
Claim 5
Dependent Claim
13 words
A method as defined in claim 1 wherein the blood is heparinized blood.
Claim 6
Dependent Claim
39 words
A method as defined in claim 4 wherein: the citrate is approximately a 3.8% sodium citrate concentration, the inhibitor is prostacyclin, and the prostacyclin is present in an approximate amount of 10 nanograms per milliliter of heparinized blood collected.
Claim 7
Dependent Claim
36 words
A method as defined in claim 4 wherein: the citrate is approximately a 3.8% sodium citrate concentration, the inhibitor is imidazole, and the imidazole is present in an approximate concentration of 50 mM in the citrate.
Claim 8
Independent Claim
101 words
A method of inhibiting a platelet-related procoagulant activity in a sample of whole blood collected from a patient in a collection medium including a calcium chelating agent, which platelet-related procoagulant activity would normally develop as a result of drawing the blood sample from the patient and conclude within approximately thirty minutes after the blood sample was drawn, comprising the steps of: mixing an inhibitor of the platelet procoagulant activity with the blood sample approximately simultaneously with collecting the sample in the collection medium, the inhibitor comprising one of the group consisting of a prostaglandin or an inhibitor of thromboxane A2 synthesis.
Claim 9
Independent Claim
101 words
A method of inhibiting a platelet-related procoagulant activity in a sample of whole blood collected from a patient in a collection medium including a calcium chelating agent, which platelet-related procoagulant activity would normally develop as a result of drawing the blood sample from the patient and conclude within approximately thirty minutes after the blood sample was drawn, comprising the steps of: mixing an inhibitor of the platelet procoagulant activity with the blood sample approximately simultaneously with collecting the sample in the collection medium, the inhibitor comprising one of the group consisting of a prostaglandin or an inhibitor of thromboxane A2 synthesis.
Claim 10
Dependent Claim
12 words
A method as defined in claim 7 wherein the prostaglandin is prostacyclin.
Claim 11
Dependent Claim
49 words
A method as defined in claim 8 wherein: the prostacyclin is present in the collection medium in an approximate concentration of 10 nanograms per milliliter of blood to be collected, and the calcium chelating agent is sodium citrate present in the collection medium in an approximately concentration of 3.8%.
Claim 12
Dependent Claim
16 words
A method as defined in claim 7 wherein the inhibitor of thromboxane A2 synthesis is imidazole.
Claim 13
Dependent Claim
42 words
A method as defined in claim 10 wherein: the imidazole is present in the collection medium in the approximate concentration of 50 mM, and the calcium chelating agent is sodium citrate present in the collection medium in an approximate concentration of 3.8%.
Claim 14
Dependent Claim
113 words
A collection medium for whole blood and which is operative for inhibiting a platelet-related procoagulant activity in a sample of whole blood collected from a patient in the medium, the platelet-related procoagulant activity being one which would normally develop as a result of drawing the blood from the patient and conclude within approximately thirty minutes after the blood sample is drawn, the collection medium comprising: a container in which to collect the blood sample, a calcium chelating agent contained within the container to mix with the blood sample when collected, and an inhibitor of the procoagulant activity comprising one of the group consisting of a prostaglandin or an inhibitor of thromboxane A2 synthesis.
Claim 15
Dependent Claim
113 words
A collection medium for whole blood and which is operative for inhibiting a platelet-related procoagulant activity in a sample of whole blood collected from a patient in the medium, the platelet-related procoagulant activity being one which would normally develop as a result of drawing the blood from the patient and conclude within approximately thirty minutes after the blood sample is drawn, the collection medium comprising: a container in which to collect the blood sample, a calcium chelating agent contained within the container to mix with the blood sample when collected, and an inhibitor of the procoagulant activity comprising one of the group consisting of a prostaglandin or an inhibitor of thromboxane A2 synthesis.
Claim 16
Dependent Claim
19 words
A collection medium as defined in claim 12 wherein the inhibitor is a prostaglandin, and prostaglandin is a prostacyclin.
Claim 17
Dependent Claim
42 words
A collection medium as defined in claim 13 wherein: the prostacyclin is present in an approximate concentration of 10 nanograms per milliliter of blood to be collected, and the calcium chelating agent is sodium citrate present in an approximate concentration of 3.8%.
Claim 18
Dependent Claim
17 words
A collection medium as defined in claim 12 wherein the inhibitor of thromboxane A2 synthesis comprises imidazole.
Claim 19
Dependent Claim
36 words
A collection medium as defined in claim 15 wherein the calcium chelating agent is sodium citrate, and the imidazole is present in the approximate amount of 10.125 grams per 100 ml. of 3.8% concentration sodium citrate.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-11-01 | 1992-05-02 | 1992-11-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-11-01 | 1996-05-02 | 1996-11-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-11-01 | 2000-05-02 | 2000-11-01 | $7700.00 | Window Closed / Lapsed |