What Damage can be Done with Tourniquets

The most important thing that could cause damage to a patient with a catastrophic bleed is not to treat them correctly when you apply a tourniquet. Delaying applying an effective tourniquet will lose valuable blood from the body and make the situation more serious. Hesitating in using a tourniquet over fears of doing it wrong will also lose valuable time and blood.

Applying the tourniquet not tightly enough will mean the blood is still lost from the body. As the tourniquet blocks the venous return, all blood will be forced out and none will be able to return through the veins. Therefore, you can do real damage to the person if you do not apply the tourniquet tightly enough.

One thing we spoke about in the past was that the limb could be damaged or lost if the tourniquet was left on too long. The times quoted were in the region of 15 minutes. This is not the case and there are no exact guidelines. If there were, these would vary depending on the size and the nature of the injury.

Trials have shown that losing a limb after the application of a tourniquet is rare. If the limb is lost, it may be the injury that has caused the limb loss and not the tourniquet. The tourniquet has, in fact, stopped the bleed, therefore, saved the person's life.

Reperfusion injury is where blood is returned to the body after a period of lack of oxygen. This can be fatal, but recent research has shown that this is only a possibility after 60 minutes of the tourniquet being applied. As the tourniquet is removed in a hospital, it will be the Doctor who considers if reperfusion injury is a possible risk. As a general rule, research shows that there is little risk of permanent injury from the application of a tourniquet for up to two hours. As a first aider, this means that there is little risk from tourniquets as long as we evacuate the patient to the hospital quickly. If tourniquets are not used, there is a far greater risk to life when the blood is lost.

Where the loss of a limb is likely, the tourniquet would need to be applied for 6 hours, but this is just a general guide. The fact is that we can usually get help in minutes rather than hours.

The point where the tourniquet is applied could also be damaged. This needs to be weighed up against the damage done if the tourniquet is not applied and the resulting blood loss. Applying a tourniquet hurts and there will be a local pain but this is necessary. Not applying it tightly enough could be fatal.

To summarise, the risks to the patient of not applying a tourniquet or applying it incorrectly far outweigh the risk of applying it correctly. As it is removed by a Doctor in a hospital, if there is any damage the patient is in the best place for the correct treatment to be given. Because you have kept more blood in the body, the person's chance of survival is increased. Finally, it is fairly safe to leave it on for up to two hours so this gives us plenty of time to evacuate them to hospital.