ABSTRACT
Samples for hemostasis evaluation must be collected very carefully to prevent any platelet activation or tissue thromboplastin-induced activation of the clotting mechanism. The initial 1-2 ml of blood collected should be discarded to avoid this problem. Unless the sample can reach the laboratory within 1 hour and be tested within 4 hours, plasma should be harvested, shipped on ice, and frozen at –20° C until analysis can be performed.
