Tourniquet

A tourniquet is a compression device, usually a bandage, used to restrict flow of blood for a period of time. It's used to control bleeding.
In most cases, the tourniquet should only be applied directly to the bleeding site. It should not be used "upstream" of the blood flow to totally restrict blood flow, as this can lead to necrosis. Instead pressure should be applied directly to the wound until blood flow stops.
Tourniquet at Wikipedia
Category:Medical procedures
Category:First aid