Plasma clot retraction assay with standard platelet count.

After classifying the phases of blood clot retraction within the mechanism of blood coagulation and the factors on which this phenomenon is depending, the authors briefly review the methods employed for its investigation. An improvement based on the determination of plasma clot retraction, performed in a plasma with a standard count of platelets (100,000/mm3) is presented. The authors have employed it for the investigation of 100 normal subjects and 25 patients with platelet dysfunctions, and have obtained very good results.