A 25 year-old man from New Jersy after a fight incurs blunt trauma to his upper outer arm. On physical examination, there is a 2 x 3 cm contusion. He bleeds but the initial soft tissue bleeding stops in a few minutes and the size of the bruise does not increase. Which of the following chemical mediators is most impoant in this episode of hemostasis?
Prostaglandin Prostacyclin Plasminogen Thromboxane