clot retraction test

clot retraction test,

a blood test used to evaluate bleeding disorders such as thrombocytopenia and Glanzmann's thrombasthenia. It measures the time required for blood in a test tube to form a clot and for the clot's edges to retract from the sides of the glass tube. This test is no longer used in most laboratories.

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clot

1. a semisolidified mass, as of blood or lymph.

2. to form such a mass.

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dilute whole blood clot retraction test

an indirect measure of fibrinolytic activity. Whole blood is diluted with saline, chilled, then warmed. The time for clot retraction, and later clot lysis, is measured.

clot formation

a complex interaction, part of the phenomenon of blood clotting. The process is irreversible but the clot may be dissolved naturally.

clot lysis

the time required for a clot to lyse at 98.6°F (37°C) is a reflection of the plasmin content of the blood. Clot retraction and fibrinogen content of the blood sample are also influential.

clot retraction

the drawing away of a blood clot from a vessel wall, a function of thrombasthenin, released by blood platelets.

clot retraction test

a test for platelet numbers and function. Clotted whole blood should retract away from the sides of a glass tube in 1 to 2 hours.