How to Apply a Tourniquet Correctly

Understanding Proper Use Can Help Save a Life

Learning how to apply a tourniquet correctly can save a life by stopping or slowing bleeding until 911 emergency help arrives. Tourniquets are bands 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 first aid. 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 first aid device.

First aid exercise of applying touriquet
Ross Helen / Getty Images

When to Use a Tourniquet

Tourniquets are used when all other options to stop bleeding have failed. This includes elevating the limb above the heart and applying direct pressure to the wound for 15 minutes to allow a clot to form. If these efforts don't work, a tourniquet may be the only option.

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

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 Are Tourniquets Made Of?

If you are an emergency medical professional, you will have access to a commercial tourniquet. However, if you're a bystander to an accident, you will most likely need to improvise and devise a makeshift tourniquet to control the bleeding.

As a rule, commercial tourniquets are not available in home first aid kits due to the high potential for misuse. Even so, you can purchase commercial tourniquets, including traditional windlass-style tourniquets, rachet-style tourniquets, and dial-tightening tourniquets.

Research has shown that improvised tourniquets are effective up to 60% of the time. While this may not sound reassuring, in a life-or-death situation, the odds may be enough to outweigh the risks of inaction.

A makeshift tourniquet is simple and comprised two parts:

  1. A bandage: You can use any piece of material that is at least 2 to 3 inches wide and overlaps when wrapped around the limb. The cloth should be sturdy and flexible, but not too slippery or stretchy. It could be a bandage, a strip of cloth, or even a T-shirt.
  2. A windlass: This is a rod or stick that you twist to tighten the tourniquet. It needs to be sturdy enough not to break while twisting. Options include a heavy stick, a pair of chopsticks, a screwdriver, or a thick spoon handle.

What Not to Use

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 911. If someone else is with you, have them call 911 while you take immediate action.

If possible, practice universal precautions to limit your exposure to blood. If personal protective equipment is available (like gloves and masks), put them on before delivering first aid.

1:38

Click Play to Learn the Right Way to Apply a Tourniquet

This video has been medically reviewed by Anju Goel, MD, MPH.

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 911 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.

Secure the tourniquet around the limb with a common square knot. This is done by tying the fabric as you would a shoelace but without making a bow.

Step 4: Add a Windlass

Next, grab the object you intend to use as a windlass. Place it on top of the square knot, then tie the loose ends of the tourniquet around it with another square knot.

Step 5: 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 tying one or both ends to the injured person's arm or leg.

Step 6: Time It

Tourniquets cannot be applied for longer than two hours.

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.

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 below 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.
  • 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.

Summary

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 a trained medical professional to apply a tourniquet, anyone can do so if they have the right materials and knowledge.

The best way to avoid 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.

  • 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.

  • 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.

8 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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Rod Brouhard, EMT-P

By Rod Brouhard, EMT-P
Rod Brouhard is an emergency medical technician paramedic (EMT-P), journalist, educator, and advocate for emergency medical service providers and patients.