By Shellie Wass

According to the American College of Surgeons Committee on Trauma, someone who is severely bleeding can bleed out in under five minutes. Protecting yourself and others from injuries can seem overwhelming, but with a simple tool, a tourniquet, and strategies, you may be able to help save a life.  It is important to remember that a tourniquet does not replace necessary medical care, but it does give a person more time to get to a medical professional. Kramer advises that when applied correctly, a tourniquet extends someone’s time to get to a medical professional.
 

When to Use a Tourniquet 

There are many reasons that life-threatening bleeding can occur. Kramer says that tourniquets are frequently mentioned in conversations around assault weapons, but that isn’t their only purpose.

NORA KRAMER

Nurse, Jefferson Health Trauma Team

“Injuries ranging from car accidents to woodshop accidents to even shark bites are all reasons a tourniquet can be necessary. In such instances, you may notice blood spurting out of the wound, blood pooling on the ground, bandages becoming soaked with blood, or a bleeding victim becoming confused or unconscious.”

How to Use a Tourniquet

Understanding how to successfully apply and use a tourniquet is essential. Before applying one, ensure that you are safe and call EMS through 9-1-1. Find the wound and open or remove clothing in the way and apply pressure with a clean cloth. It’s best to do this while wearing gloves whenever possible, says Kramer.

Then, apply the tourniquet two to three inches above the wound to stop the bleeding and always avoid the elbow and knee. For example, if the injury is on the forearm near the elbow, you would apply the tourniquet above the elbow to stay close to the wound.

Once applied, pull the tourniquet as tight as possible and do not pass the clip of the tourniquet with the strap. This is very important because this is where you will twist the rod to cut off circulation to stop the bleeding.

With many tourniquets, there will be a place to write down the time it was used, which will be important to the medical provider when the victim receives care. It is essential to keep the tourniquet on for the medical provider who is assessing the patient.
 

How to Apply a Tourniquet to Yourself

If you get injured and have a tourniquet, you can apply the tourniquet to yourself. You want to slow down the bleeding as quickly as possible to avoid becoming dizzy or fainting.

This tourniquet is called a combat application tourniquet, commonly called a CAT tourniquet.

Put the tourniquet on and pull as tightly as possible without passing the clip. Use the rod to twist around to tighten and place into the clip and put the excess strap over the rod. This will cut off the circulation to the wound, stopping the bleeding. If you are able, add the time you applied the tourniquet.
 

What If You Don’t Own a Tourniquet? 

While Kramer advises that anyone with a medical bag carry a tourniquet, she understands that an incident may occur when you don’t have one on hand. What can you do in this situation? T-shirts can save lives, Kramer says. “With a t-shirt, apply pressure to the wound to stop the bleed while you await medical attention,” Kramer explains.  “It’s essential to continue to apply pressure the whole time to help extend the person’s time while waiting to get to a medical professional. If someone is bleeding from an arm, a leg, their abdomen, anywhere, all you need to do is apply pressure and stop the bleed.”

https://www.jeffersonhealth.org/your-health/living-well/how-to-save-a-life-with-a-tourniquet

Matthew D. Sztajnkrycer, M.D., Ph.D., an emergency medicine specialist at Mayo Clinic's campus in Rochester, Minnesota, says two common scenarios come to mind in which he's seen tourniquets save lives:

• Motor vehicle or motorcycle crashes. Dr. Sztajnkrycer — often called Dr. Matt — reports that patients arrive with tourniquets after farm and industrial incidents or car and motorcycle crashes have resulted in a partial or complete limb amputation. A tourniquet applied at a traumatic injury scene like this has saved the lives of patients he's treated in the Mayo Clinic emergency department.

• 'Household misadventures'. Dr. Sztajnkrycer indicates that emergency department patients who've experienced a household misadventure are prevalent as well. The most serious of these injuries — in terms of hemorrhaging — typically involve plate glass windows.

"The brachial artery can sever; they're bleeding to death in their own home," says Dr. Sztajnkrycer. "Someone usually shoves them in the car and drives them to the hospital. The car they rode in is often filled with blood."

In these circumstances, tourniquets are applied by emergency department staff, stemming the blood loss.

Tourniquets have a long but also conflicting history. Some have called tourniquets "an instrument of the devil that sometimes saves a life," such as in a 2001 report to The Red Cross by Dr. Coupland and colleagues. More recently, tourniquets have been viewed as invaluable lifesavers provided they are applied appropriately and correctly.

A tourniquet's primary purpose is to stop life-threatening external bleeding, says Dr. Sztajnkrycer. Most such bleeding situations are trauma induced. Emergency medical services regularly use tourniquets today alongside other bleeding control methods. He says tourniquets are useful because it's difficult to maintain consistent pressure for an extended time using simple pressure; and tourniquets both avoid disrupting a forming clot and allow safer patient transport.

Tourniquets often are misunderstood and misapplied, says Dr. Sztajnkrycer, noting a recent study published in Journal of Trauma and Acute Care Surgery that suggests that they're misused up to one-quarter of the time.

"Having a tourniquet is great," he says, "but knowing how to use it is way better."

Some tourniquet mishaps Dr. Sztajnkrycer has witnessed include:

• Placing the tourniquet in the wrong location

• Using a tourniquet in the wrong situation

• Applying the tourniquet's band too loosely

• Breaking the windlass

• Loosening the tourniquet after the bleeding is controlled

The big fear with tourniquets is that limiting blood supply to the limb can result in amputation. This does not appear to be the case in most civilian tourniquet applications, notes Dr. Sztajnkrycer. Having a tourniquet in place for two or fewer hours — the time in which most patients can get to a hospital — should not have any ill effects beyond those caused by the injury requiring the tourniquet. It typically takes at least 4 to 6 hours for tourniquets to cause harm.

For correct tourniquet use, he says one must decide if:

• The bleeding is life-threatening

• The location is suitable for tourniquet use

• Another bleeding control method, such as hemostatic gauze, would better fit the situation

To help equip the public to properly use bleeding control methods such as tourniquets to stop life-threatening bleeding, The American College of Surgeons (ACS) Committee on Trauma administers the Stop the Bleed program.

Unfortunately, sometimes an individual may encounter massive bleeding and not have a modern commercial tourniquet on hand. Dr. Sztajnkrycer says he's often asked about improvised tourniquets, such as belts, scarves or neckties.

He indicates that a 2017 study on law enforcement tourniquet use published in Prehospital Disaster Medicine showed that improvised tourniquets failed six out of seven times. Despite this low success rate, Dr. Sztajnkrycer says improvised tourniquet use is worth learning, as it can save lives.

"An improvised tourniquet is better than nothing, but you need to understand the physics," he says. "We need to be better about teaching improvised tourniquet techniques."

Tourniquet use requires training because it isn't always intuitive, per Dr. Sztajnkrycer. Spending a morning learning how to put on a tourniquet is probably not enough. It's not uncommon for lay providers to be taught how to use them and then forget how to do so a couple of months later. This is especially true given that the tourniquet is almost always used under stress and brains have difficulty processing under extreme stress.

"Tourniquet application is not as easy as people think," he says. "You think it is a simple device, but to get it right and tight, and use the windlass appropriately, there are nuances."

Dr. Sztajnkrycer suggests that reviewing tourniquet application at least quarterly is crucial for preparedness. He asserts that the best way to reinforce how to do something such as using a tourniquet is to teach others and troubleshoot their mistakes.

"If you teach 15 to 20 people tourniquet application regularly, training others to be force multipliers, you reinforce it for yourself," he says.

Knowing how to downgrade from a tourniquet to hemostatic or pressure dressing also is crucial for treating hemorrhaging trauma patients, and he suggests that tourniquet training for medical providers — as opposed to the general public — should incorporate this skill.

Beyond training a facility's trauma team members, he encourages tourniquet training for others working near the trauma bay who don't have specialized trauma knowledge, such as phlebotomists, radiation technologists or emergency department desk representatives.

"Train an extra pair of hands to put on tourniquets so you can spend your time on more-advanced skills," he says.

https://www.mayoclinic.org/medical-professionals/trauma/news/the-crucial-role-of-tourniquets-in-trauma-care/mac-20531726

Aaron L. Zuckerberg, Myron Yaster, in Smith's Anesthesia for Infants and Children (Eighth Edition), 2011

Tourniquets

Pneumatic tourniquets are commonly used to provide a dry operative field and limit intraoperative blood loss during extremity surgery (Kam et al., 2001). Modern pneumatic tourniquets consist of three basic components: a cuff that is similar to a blood pressure cuff and is wrapped around a patient's limb and then inflated, a compressed gas source, and a mechanism with a pressure gauge that is designed to maintain pressure in the cuff at a set value. After elevation and application of an Esmarch's bandage to exsanguinate the limb, the tourniquet is applied over smooth padding and inflated. Older methods inflate the tourniquet to a pressure based on the patient's systolic pressure. Recent practice is to determine the limb occlusion pressure and add a margin of 75 mm Hg for lower extremity surgery and 50 mm Hg for upper extremity procedures. Limb occlusion pressure, first suggested by Cushing, is the minimum pressure necessary to occlude arterial blood flow, as determined automatically or via palpation or pulse oximeter. To prevent accidental injury, the cuff should have a width that is greater than one half of the limb's diameter and an accurate pressure gauge, and the cuff should be inflated to the lowest possible inflation pressure recommended. The duration of inflation should also be carefully monitored (Tuncali et al., 2006; Reilly et al., 2009).

The length of time that the tourniquet can remain safely inflated is controversial. The most common recommendation, 2 hours, is based on the finding that cellular ischemic changes such as mitochondrial swelling, myelin degeneration, glycogen storage depletion, and Z-line lysis are reversible if the tourniquet is inflated for no more than 1 to 2 hours (Patterson and Klenerman, 1979). The deleterious effects of tourniquet inflation include pain while the tourniquet is inflated (“tourniquet pain”), metabolic and hemodynamic changes that occur during tourniquet inflation and deflation, and damage to blood vessels and muscle if the tourniquet is inflated for excessive periods. The use of pneumatic tourniquets has been associated with perioperative neuropathy (Welch et al., 2009).

In awake patients undergoing extremity surgery under regional anesthesia blockade, tourniquet pain is described as a dull, ill-defined ache that occurs approximately 45 to 60 minutes after a tourniquet is inflated. Over time, this pain becomes unbearable, but it subsides immediately after tourniquet deflation. This pain occurs despite adequate regional anesthesia for the surgical procedure itself. The cause of tourniquet pain remains uncertain, and early intervention is imperative. IV opioids have limited efficacy, and induction of general anesthesia or deflation of the cuff is the only effective solution to this problem. Prophylaxis may be possible. The addition of opioids to local anesthesia solutions at the time of neural blockade appears to decrease the incidence of tourniquet pain in patients undergoing a regional anesthesia.

The hemodynamic consequences of tourniquet application include increases in blood and central venous pressures. Kaufman and Walts (1982) reported an overall 30% increase in blood pressure during tourniquet inflation. The blood pressure response is more exaggerated in patients under general anesthesia than in those undergoing regional blockade (Valli et al., 1987). Tourniquet-induced hypertension can be prevented by the preoperative administration of 0.25 mg/kg of ketamine (Satsumae et al., 2001). Limb exsanguination and tourniquet inflation can redistribute 15% of the total blood volume to the general circulation rapidly. Central venous pressure increases of up to 14 mm Hg have been reported in adults with the application of bilateral tourniquets. The clinical significance of central venous pressure reduction that accompanies tourniquet deflation primarily depends on the presence of preexisting cardiac dysfunction.

The metabolic changes that accompany tourniquet use include an increase in core temperature during tourniquet inflation and the development of transient metabolic acidemia and hypercarbia after tourniquet release. The increased output of CO2 and lactic acid from the ischemic limb causes a transient decrease in arterial pH, with a maximum decrease within 4 minutes, returning to baseline values within 10 to 30 minutes. The sudden release of CO2 into the circulation when lower limb tourniquets are released can markedly increase intracranial pressure in patients with head trauma. Normocapnia maintained by hyperventilation after tourniquet deflation can prevent increased cerebral blood flow velocity and intracranial pressure.

Tourniquet-induced hyperthermia, usually 1° to 2° C, occurs within 90 minutes of tourniquet inflation and appears to be the result of decreased cutaneous heat loss from skin distal to the tourniquet. The effect is more profound if bilateral tourniquets are used (Estebe et al., 1996). The combination of metabolic acidosis and hypercarbia that occurs after tourniquet release is the result of reperfusion and the washing out and reentry into the central circulation of lactic acid, potassium, and other toxic substances that accumulated in tissues during tourniquet-induced limb ischemia. Accompanying hemodynamic effects include hypertension and hypotension, tachycardia, bradycardia, and, rarely, ventricular dysrhythmias. These effects are self-limited and usually resolve over a few minutes. Other than increasing minute ventilation in patients who are being mechanically ventilated, most pediatric patients rarely or never require specific therapy for tourniquet deflation.

https://www.sciencedirect.com/topics/nursing-and-health-professions/pneumatic-tourniquet