For most practical purposes, use of a tourniquet implies a choice between death of patient and loss of limb. Part of the emphasis on this choice in first-aid c

For most practical purposes, use of a tourniquet implies a choice between death of patient and loss of limb. Part of the emphasis on this choice in first-aid classes is to keep people from over-using tourniquets for injuries which do not pose a risk of loss of life. A laceration to the hand can look awful, but some pressure and elevation can minimize blood loss even if definitive care is hours away without risking loss of the hand or forearm by using a tourniquet. In a massive trauma situation, such as from multiple penetrating wounds, if the patient bleeds out and dies, other tissue damage does not matter much. If the patient survives injuries that make it a good idea to block the abdominal aorta - https://en.wikipedia.org/wiki/Abdominal_aorta https://en.wikipedia.org/wiki/Abdominal_aorta then there is a good chance he/she has survived due to good and rapid field treatment, and rapid evacuation to a definitive care facility that can manage any other tissue damage caused by lack of circulation below the diaphragm.