US5293772A
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Instrumentation and method for evaluating platelet performance during clotting and dissolution of blood clots and for evaluating erythrocyte flexibility
Assignee: Virginia Commonwealth University
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Filing: 1992-12-01
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Granted: 1994-03-15
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Expires: 2012-12-01
Abstract
Abstract The performance of platelets can be best understood by monitoring both the force development and the elastic modulus of the blood clot during both clotting and dissolution of the blood clot. Intermittent application and removal of a compressive force on a blood sample (8) positioned between a pair of plates (12 and 14) throughout clot formation and dissolution provides a standard for using voltage output from a transducer (22) to determine force and elastic modulus parameters. Force development arises from the internal actions of the platelets during clot retraction. Elastic modulus provides a measure of the stiffness of the clot. Clotting can be measured as an increase in force development and clot elastic modulus. Clot dissolution can be determined by a dramatic decrease in force development and in elastic modulus. Providing the blood sample with a clot dissolving agent such as tPA allows determining the fibrinolytic potential of whole blood and, thus, aids in identifying patients at risk for thrombosis due to a decreased ability to dissolve clots. Clot elastic modulus provides a measure of erythrocyte flexibility.
Inventors
- 👤 Marcus E. Carr, Jr.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 21:36
CPC Classifications
G; G01; G01N; G01N33/00; G01N33/48; G01N33/483; G01N33/487; G01N33/49; G01N33/4905
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
46 words
An instrument for measuring clot elastic modulus and clot retraction force, comprising: a pair of spaced apart plates; a displacement sensor connected to at least one of said pair of spaced apart plates; and means for cyclicly compressing a blood sample between said spaced apart plates.
Claim 2
Dependent Claim
46 words
An instrument for measuring clot elastic modulus and clot retraction force, comprising: a pair of spaced apart plates; a displacement sensor connected to at least one of said pair of spaced apart plates; and means for cyclicly compressing a blood sample between said spaced apart plates.
Claim 3
Dependent Claim
39 words
An instrument as recited in claim 1 wherein said means for cyclicly compressing includes a means for displacing a first plate of said pair of spaced apart plates towards a second plate of said pair of spaced apart plates.
Claim 4
Independent Claim
67 words
A method for analyzing blood and plasma samples, comprising the steps of: positioning a blood sample between a pair of spaced apart plates; compressing, in a cyclical fashion with respect to time, said blood sample between said pair of spaced apart plates while said blood sample is clotting; and determining a clot retraction force and a clot elastic modulus for said blood sample with respect to time.
Claim 5
Independent Claim
67 words
A method for analyzing blood and plasma samples, comprising the steps of: positioning a blood sample between a pair of spaced apart plates; compressing, in a cyclical fashion with respect to time, said blood sample between said pair of spaced apart plates while said blood sample is clotting; and determining a clot retraction force and a clot elastic modulus for said blood sample with respect to time.
Claim 6
Independent Claim
72 words
A method for analyzing blood and plasma samples, comprising the steps of: providing a blood sample with a clot dissolving or clot destroying agent; positioning said blood sample between a pair of spaced apart plates; allowing said blood sample to clot; compressing said blood sample between said pair of spaced apart plates during clotting; identifying a compression elastic modulus for said blood sample; and relating said compression elastic modulus to erythrocyte flexibility.
Claim 7
Independent Claim
72 words
A method for analyzing blood and plasma samples, comprising the steps of: providing a blood sample with a clot dissolving or clot destroying agent; positioning said blood sample between a pair of spaced apart plates; allowing said blood sample to clot; compressing said blood sample between said pair of spaced apart plates during clotting; identifying a compression elastic modulus for said blood sample; and relating said compression elastic modulus to erythrocyte flexibility.
Claim 8
Dependent Claim
37 words
A method as recited in claim 4 wherein said step of compressing is performed by displaying a first plate of said pair of spaced apart plates towards a second plate of said pair of spaced apart plates.
Claim 9
Independent Claim
84 words
A method for analyzing blood and plasma samples, comprising the steps of: providing a blood sample with a clot dissolving or clot destroying agent; positioning said blood sample between a pair of spaced apart plates; allowing said blood sample to clot and to dissolve; compressing said blood sample between said pair of spaced apart plates in a cyclical fashion with respect to time while said blood sample is clotting and dissolving; and identifying a dissolution time for a clot formed from said blood sample.
Claim 10
Independent Claim
84 words
A method for analyzing blood and plasma samples, comprising the steps of: providing a blood sample with a clot dissolving or clot destroying agent; positioning said blood sample between a pair of spaced apart plates; allowing said blood sample to clot and to dissolve; compressing said blood sample between said pair of spaced apart plates in a cyclical fashion with respect to time while said blood sample is clotting and dissolving; and identifying a dissolution time for a clot formed from said blood sample.
Claim 11
Dependent Claim
29 words
A method as recited in claim 6, wherein said step of identifying includes the step of analyzing a clot retraction force for said blood sample with respect to time.
Claim 12
Dependent Claim
28 words
A method as recited in claim 6, wherein said step of identifying includes the step of analyzing an elastic modulus of said blood sample with respect to time.
Claim 13
Dependent Claim
20 words
A method as recited in claim 6, further comprising the step of providing said blood sample with a clotting agent.
Claim 14
Independent Claim
107 words
A method for analyzing blood and plasma samples, comprising the steps of: providing a blood sample with a clot dissolving or clot destroying agent; positioning said blood sample between a pair of spaced apart plates; allowing said blood sample to clot; compressing said blood sample between said pair of spaced apart plates during clotting by displacing a first plate of said pair of spaced apart plates toward a second plate of said pair of spaced apart plates wherein said step of compressing is performed cyclically with respect to time; identifying a compression elastic modulus for said blood sample; and relating said compression elastic modulus to erythrocyte flexibility.
Claim 15
Independent Claim
107 words
A method for analyzing blood and plasma samples, comprising the steps of: providing a blood sample with a clot dissolving or clot destroying agent; positioning said blood sample between a pair of spaced apart plates; allowing said blood sample to clot; compressing said blood sample between said pair of spaced apart plates during clotting by displacing a first plate of said pair of spaced apart plates toward a second plate of said pair of spaced apart plates wherein said step of compressing is performed cyclically with respect to time; identifying a compression elastic modulus for said blood sample; and relating said compression elastic modulus to erythrocyte flexibility.
References Cited (Backward Citations)
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