The number one cause of preventable death on the battlefield is exsanguination from extremity hemorrhage. Hemorrhage from extremity wounds was the cause of death in more than 2,500 casualties in Vietnam who had no other injuries. These deaths could have been prevented through the use of a tourniquet. The tourniquet was first used on the battlefield in 1674 by a French military surgeon. Since then, it has been routinely used to control bleeding during surgery and following extremity trauma resulting in severe bleeding.