Applying a tourniquet is an extremely useful technique to know in case of a serious medical emergency.
If you find yourself in the middle of wilderness with a friend whose cut limb won’t stop bleeding, there will not be time for outside help to come; in this situation knowing how to make and apply a tourniquet is very important.
Use a tourniquet only when direct pressure over the bleeding point and all other methods did not control the bleeding. If you leave a tourniquet in place too long, the damage to the tissues can progress to gangrene, with a loss of the limb later.
An improperly applied tourniquet can also cause permanent damage to nerves and other tissues at the site of the constriction.
If you must use a tourniquet, place it around the extremity, between the wound and the heart, 5 to 10 centimeters above the wound site (Figure 4-4). Never place it directly over the wound or a fracture.
Use a stick as a handle to tighten the tourniquet and tighten it only enough to stop blood flow.
When you have tightened the tourniquet, bind the free end of the stick to the limb to prevent unwinding.