An adult can die from blood loss in just a few minutes if there is no intervention. If you witness someone bleeding uncontrollably - whether from a car accident, gun violence, natural disaster, or other emergency or accident - it's important to ensure your own safety first. If you are safe, call EMS immediately or direct someone else to call. Next, look for the source of the bleeding. If the person's injury is on their arm or leg, a tourniquet can potentially save their life.

Before using a tourniquet, try to first stop the bleeding by applying direct pressure to the wound. If you cannot stop the bleeding with direct pressure, a tourniquet should be used. Learning how to apply a tourniquet correctly can save a life by stopping or slowing bleeding until EMS arrives. Tourniquets are devices that are tied around an arm or leg when bleeding is uncontrollable due to a severe wound like a gunshot, stabbing, or heavy machinery accident.

Ideally, tourniquets should be applied by first responders who are trained in emergency care But there are times when delaying is not an option, and knowing how and when to apply a tourniquet can be the difference between life and death. This article outlines when tourniquets should (and should not) be used, as well as the proper way to apply this important life-saving device.

The goal of a tourniquet is to restrict blood flow to the injured limb and prevent life-threatening blood loss. It is only intended as a stop-gap measure to buy time while you wait for emergency help to arrive.

The decision to use a tourniquet is one you need to make quickly. However, it is important to remember that a tourniquet is not an alternative to stopping the bleeding but rather the last resort when the bleeding is uncontrollable and the risk of death is high.

Emergencies in which a tourniquet may be indicated include:

• Car accidents with major crush or blunt force injuries

• Gunshot wounds

• Deep cuts or lacerations, including stabbings

• Crushed or severed limbs

How Do You Apply a Tourniquet?

1. Before you apply a tourniquet, it is important that you tell the injured person that it is going to hurt.

2. You can apply a tourniquet to bare skin or over clothing.

3. Place the tourniquet high and tight on the extremity (arm or leg), near the armpit or groin.

4. Pull the “tail" strap of the tourniquet tight and twist the windlass until the bleeding stops. Secure the windlass to keep the tourniquet tight and in place.

5. Note the time – as best you can – of when the tourniquet was applied, some tourniquets may have a white space on the strap where you can write it down.

6. Do not remove the tourniquet.

If bleeding continues after you apply the tourniquet, continue to apply pressure and tighten the strap. If the bleeding still does not stop, and a second tourniquet is available, apply the second tourniquet below the first one.

Emergency responders may have questions for you when they arrive, like when you applied the tourniquet, so be sure to stay with the person until help arrives. Remember, in emergency bleeding situations, minutes matter. Applying a tourniquet on someone with a serious bleeding injury could potentially help save a life.

When Not to Use a Tourniquet

Tourniquets are intended for limb injuries only and cannot be used for head or torso injuries. An injury to the head or torso requires direct pressure with a cloth to help slow or stop bleeding until emergency help arrives.

What Not to Use as a Tourniquet

Belts are not ideal for tourniquets as they are too rigid to be twisted tightly. Synthetic or silk scarves or ties are too slippery and can easily come undone. Zip ties and cords are also not ideal as they can cause severe blood vessel and nerve damage. Pencils and pens are not ideal for windlasses as they can easily break as you twist them.

How to Apply a Tourniquet Step-by-Step

You do not need special medical training to apply a tourniquet in an emergency situation, but you do need to know the right way to use one. The first step in any emergency situation is to call EMS. If someone else is with you, have them call EMS while you take immediate action. If possible, practice universal precautions to limit your exposure to blood. If personal protective equipment (gloves) is available, put them on before delivering care.

Step 1: Find the Source of the Bleeding

If possible, have the injured person lie down. This will make it easier for you to find the exact source of bleeding as quickly as possible. If EMS is on the line, place them on speaker phone so that you can keep them apprised of your actions and they can help you make the appropriate decisions every step of the way.

Step 2: Apply Pressure

Once you find the source of the bleeding, apply direct pressure to the wound. If the bleeding does not significantly slow or stop after 15 minutes of uninterrupted pressure, you will need to find or make a tourniquet. If the injured person is awake and alert, tell them what you intend to do. They need to know that the process can be extremely painful but that the intention is to 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 remove any clothing around the wound. Next, position the tourniquet several inches above the injury closest to the heart. For example, if the injury is below the elbow, you will need to tie the tourniquet above the elbow. Never place the tourniquet directly on the joint as this can cause permanent nerve, joint, or blood vessel injury.

Step 4: Tighten the Tourniquet

Tighten the tourniquet around the limb by twisting the windlass. Keep an eye on the bleeding and take note of when it starts to slow. Continue twisting until the bleeding has stopped or is significantly reduced. When the bleeding has stopped sufficiently, secure the windlass by hooking it to the “windlass hook” and keep it in place with the velcro strap.

Step 5: Time It

Make note of the time you put the tourniquet on. You can do this by marking "T" with the date and time on the person's forehead or another easy-to-see place. This will help the emergency staff know what to do when they arrive. All commercial tourniquets have a place to note the time.

Do Not Remove a Tourniquet!

A tourniquet should never be loosened or removed by anyone other than a healthcare provider in the emergency department.

What to Do if the Bleeding Doesn’t Stop

If a tourniquet is applied but the bleeding doesn't stop, try twisting the tourniquet more and see if that helps. If it doesn't, you can apply a second tourniquet immediately above the first one. Even if the first tourniquet has failed, do not remove it. Instead, place the second tourniquet, following steps 3 to 6, until the bleeding stops.

Common Tourniquet Mistakes

Even someone who knows how to use a tourniquet can make mistakes. By knowing what these mistakes are, you may be able to avoid them yourself.

Common mistakes include:

• Waiting too long: You need to recognize when a tourniquet is needed and be able to act quickly. When an injured person loses too much blood, they can go into shock. This happens when the blood volume and blood pressure drop so low that organs start to fail and death can occur.1

• Applying a tourniquet loosely: Loose tourniquets are not effective because they do not sufficiently stop the blood flow. This may be the result of choosing a fabric that is too slippery or stretchy.

• Not applying a second tourniquet: It is good to know beforehand that a second tourniquet is sometimes necessary, particularly if a person is large or has large limbs. 

• Loosening a tourniquet: Tightening and then loosening a tourniquet allows blood to rush back to the injury, which can severely damage blood vessels. This is why is it important to tell the person being treated to expect pain once a tourniquet is applied (at least until 911 help arrives).

• Leaving it on too long: A tourniquet should not be left in place for more than two hours. When used for longer than this, it can cause permanent damage to muscles, nerves, and blood vessels.

In an emergency, knowing how to use a tourniquet can save an injured person's life. While it's best for a trained medical professional to apply a tourniquet, anyone can do so if they have the right training and knowledge.

The best way to avoid mistakes when using a tourniquet is to be informed about when and how to use one correctly. This STOP THE BLEED program will prepare you on how to save a life! Over 2.6 million people have learned to STOP THE BLEED.

You can, too!