A tourniquet is a tool that is used on a patient in catastrophic bleeding first aid. We use it to apply pressure to the blood vessel. It consists of a wide band, often made of elastic or rubber material, which is tightly wrapped around the limb above the site of bleeding. The purpose of a tourniquet is to temporarily halt or significantly reduce blood flow to the affected area, effectively stopping the bleeding. They are used when applying direct pressure on the wound is not effective enough. It’s important to note that tourniquets should be used as a last resort and only in situations where there is an immediate threat to life due to severe bleeding. Improper or prolonged use of a tourniquet can lead to complications, such as tissue damage or limb loss. Therefore, a sound knowledge of tourniquet application and usage is crucial, and medical assistance should be sought as soon as possible after applying a tourniquet in order to manage a bleed. If you are in a position where you have been tasked with severe bleeding control, the absolute first thing you should do in all situations if possible is to call 999.