Updated: Sep 11
Tourniquets are tight bands used to completely stop the blood flow to a wound. While they can save a limb—or a life—it can be hard to know when to use a tourniquet (and when not to). It's also hard to know if you're using a tourniquet correctly.
Ideally, tourniquets should only be used by first responders who are trained in emergency first aid. If that's not possible, knowing how to apply a tourniquet correctly can be a life-saving skill to have.
This article will go over when tourniquets should—and should not—be used. You will learn the right way to apply a tourniquet as well as the risks of tourniquet use.
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When to Use a Tourniquet
Tourniquets can lead to severe tissue damage even when they're used correctly. However, in a severe bleeding and life-or-death emergency, properly using a tourniquet can stop bleeding and keep an injured person stable until they can receive medical care.1
Emergencies that could require a non-medical person to use a tourniquet include:
Crushed limbs (for example, from a work injury)
Most people will never need to use a commercial tourniquet. Still, knowing the right way to apply a tourniquet could potentially save someone's life.
What Are Tourniquets Made Of?
If you are a first responder or emergency medical professional, you'll have access to a commercial tourniquet. However, if you're a civilian, will most likely need to improvise.
In an emergency, you may not be able to get a hold of a tourniquet quickly. Instead, you might need to come up with a makeshift tourniquet to control bleeding.
The most important priority is your own safety. Before administering first aid, make sure it is safe for you to do so.
Research has shown that improvised tourniquets are effective up to 60% of the time.2 That might not sound reassuring, but as long as you have the right materials and know how to use an improvised tourniquet correctly, any attempt to stop the bleeding will likely be better than doing nothing.
A makeshift tourniquet needs two parts: a triangular bandage and something that you can use as a windlass rod (for example, a pen or a stick). Other items that you may have on hand that can be used include shirts or towels.
In any emergency—but especially one involving body fluids such as blood—practice universal precautions. If personal protective equipment (PPE) is available (like gloves and masks), put it on before you start giving first aid.
Do Tourniquets Applied by Civilians Help? A 2018 study found that when civilians without medical training performed prehospital tourniquet application, the risk for mortality was six times lower in patients with peripheral vascular injuries or blunt trauma to the extremities.3
Are Tourniquets Included in First Aid Kits?
While they do work in an emergency, commercial tourniquets are not available in first aid kits. There are other ways to sufficiently and safely control bleeding in most injuries; tourniquets should only be used in worst-case scenarios when there are no other options.
That said, a commercial tourniquet is preferable to a "homemade" one if it's available. Commercial-use tourniquets are made from recommended materials and specifications, so they're the most effective and easiest to use. They're also better suited to minimizing risk when they're used.
Since your home first aid kit won't include a tourniquet, you might consider adding one if you work with or care for people at high risk of a bleeding injury or complications from severe bleeding, such as young children and the elderly.
How to Apply a Tourniquet Step-by-Step
You do not need official or special medical certification or training to apply a tourniquet in an emergency, but you do need to know the right way to use one.
The first step to take in any emergency situation is to call 911. If someone else is with you, point to them and say "Call 911." Then, you can start tending to the injured person.
Head and Torso Injuries Tourniquets are only for limb injuries. Tourniquets cannot be used for injuries to the head or torso. An injury to the head or torso requires the application of pressure with a material that can absorb blood to slow or stop bleeding.
Using a tourniquet is only meant as a stop-gap measure to "buy time" while you wait for medical personnel to arrive. If a person is bleeding uncontrollably and help is not nearby, they may bleed out before first responders can get there to provide necessary medical care.
The goal of applying a tourniquet is to restrict blood flow to the injured limb and prevent life-threatening blood loss. Constricting the limb to cut off its blood supply is a temporary measure, but when it's done correctly, it will slow or stop the bleeding enough to allow emergency responders time to arrive.
Step 1: Find the Source of the Bleeding
Before you apply a tourniquet, you need to figure out where the bleeding is coming from. In some cases, such as near or complete limb amputation, the source of the bleeding will be obvious. Other injuries may not be visible at first, especially if there is debris, wreckage, tattered clothing, or other objects in the way.
If possible, have the injured person lie down. This will make it easier for you to check them over from head to toe. Try to stay calm and focused. You need to find the source of the bleeding as quickly as you can.
Step 2: Apply Pressure
Once you find the source of the bleeding, apply direct pressure to the wound. If the bleeding does not slow or stop when pressure is put on it, you will need to find (or fasten) a tourniquet.
If the injured person is awake and alert, tell them that you are going to put on a tourniquet. They need to know that the process of applying a tourniquet can be extremely painful (and they are probably already in a lot of pain). Tell the person that the tourniquet will hurt but that it may save their limb or even their life.
Step 3: Position the Tourniquet
The tourniquet needs to be applied to the bare skin, so you'll need to cut, tear, or otherwise remove any clothing that's near the wound.
Next, position the cloth, towel, or other material to be used for the tourniquet on the limb several inches above the injury.
Place the tourniquet at the part of the limb that is closest to the heart. For example, if the injury is below the knee or elbow, you will need to tie the tourniquet above the joint.
Use a common square knot—like tying your shoelaces, but without making a bow—to tie the tourniquet around the limb.
The American Red Cross recommends placing the tourniquet about 2 inches above the wound and never directly on a joint.4
Step 4: Add a Windlass
Next, you'll need to make a lever you can use to twist the tourniquet tighter. This is called a windlass.
Anything can be used as a windlass, as long as it is strong enough to hold the tourniquet and can be secured in place. For example, pens or pencils, sticks, or spoons can be used as a windlass.
Place the windlass on the knot, then tie the loose ends of the tourniquet around it using another square knot.
Step 5: Tighten the Tourniquet
Twist the windlass to increase the pressure. Keep an eye on the bleeding and note when it begins to slow. Continue turning the windlass until the bleeding has stopped or is significantly reduced.
Once the bleeding has slowed or stopped, secure the windlass by tying one or both of its ends to the injured person's arm or leg.
Step 6: Time It
Tourniquets cannot be applied for longer than two hours.5 You need to note what time you put the tourniquet on. It's very important that first responders and medical staff who treat the injury know when you applied the tourniquet.
Mark a "T" with the date and time on the person's forehead or another easy-to-see place. This will make sure that emergency personnel knows how long the tourniquet has been on.
Do Not Remove a Tourniquet Yourself A tourniquet should never be loosened or removed by anyone other than a healthcare provider in the emergency department.
Common Tourniquet Mistakes
Even if you know how to properly use a tourniquet, it's possible to make errors. In an emergency, you may not have enough help or resources, and you will likely face many distractions.
The following are possible mistakes you could make when using a tourniquet:
Waiting too long: You must tend to severe bleeding immediately for a tourniquet to be successful. When an injured person loses too much blood, they may go into shock.
Loose application: Loose tourniquets are not effective because they do not sufficiently constrict arterial blood flow.
Not applying a second tourniquet: One tourniquet is usually enough to control severe bleeding, however, a person with large arms may require a second tourniquet.
Loosening: Constricting and loosening the tourniquet rather than continually constricting it allows blood to reenter the injury. If blood flows back to the injury, it can damage the blood vessels.
Leaving on too long: A tourniquet should not be left in place for more than two hours. When applied for a longer time, tourniquets can cause permanent damage to muscles, nerves, and blood vessels.5
Using the wrong materials: Inappropriate materials for a tourniquet, such as a cord, can cut into the skin. Not only does this render the tourniquet ineffective it can also cause more pain or injury.
In an emergency, knowing how to use a tourniquet can save an injured person's limb—or even their life. While it's best for only trained people to apply a tourniquet, anyone can do so if they have the right materials and knowledge.
Remember: The best way to avoid making mistakes when using a tourniquet is to be informed about when and how to use one correctly.
FREQUENTLY ASKED QUESTIONS
What are the two types of tourniquets? Tourniquets are sometimes used during medical procedures and surgeries to limit blood flow to a limb. This makes it easier for the surgeons to see what they're doing since there isn't as much blood in the way. Tourniquets can also be used to "cut off" the blood supply to a limb in an emergency to prevent an injured person from losing too much blood.6
Is it OK to use a belt as a tourniquet? It's not ideal to use a belt as a tourniquet. Belts are too rigid to twist tightly with a windlass. Other items that do not work well as a tourniquet are neckties (they're too thin) and zip ties (likely to cause severe pain as well as nerve damage).78
How long does it take for a tourniquet to cause permanent damage to a limb? It takes around two hours for a tourniquet to cause permanent damage, including nerve damage, injury to blood vessels, and skin necrosis (death of skin cells). After six hours, the damage to the muscle tissue can be bad enough that it's necessary to amputate the affected limb.5
How quickly should a tourniquet be applied? It's best not to apply a tourniquet right away. First, apply direct pressure to the wound using an absorbent material for at least 10 minutes. That's how long it will take blood to clot and bleeding to stop. If it does not, then a tourniquet should be used.7
Why do phlebotomists use tourniquets for blood draws? When you have blood taken, the phlebotomist will use a piece of rubber as a tourniquet. They will briefly apply it to your upper arm (only a few seconds) to help locate the vein they will use to take the blood.9