NREMT Advanced EMT Practice Test #4

Answer - B - The first phase of clotting is the vascular phase. During the vascular phase vessels constrict. During the platelet phase platelets adherer to blood vessels walls and the final phase, the coagulation phase, is where fibrin forms a network around the would for protection. The clotting mechanism normally takes between 7-10 minutes to stop eth flow of blood. The nature of the wound and other factors affect how rapidly and well the clotting mechanisms respond to hemorrhage.