A tourniquet is a device designed to compress blood vessels in a limb, completely stopping the flow of blood beyond the point of application. It is used exclusively for controlling severe, external hemorrhage. Its function is to create circumferential pressure strong enough to occlude the underlying arteries and veins, preventing catastrophic blood loss until professional medical help is available.
Identifying the Need for a Tourniquet
The decision to apply a tourniquet is reserved for situations involving uncontrolled, life-threatening bleeding from an arm or a leg. Current guidelines stress that a tourniquet should be considered when direct pressure, the preferred initial method, has failed to stop the hemorrhage. This failure is often evident when dressings are quickly saturated with blood, or the bleeding continues to spurt vigorously.
Immediate use is indicated for a traumatic or partial amputation of a limb, where massive blood loss is almost guaranteed and direct pressure is difficult to sustain. In environments like mass casualty incidents or dangerous scenes, a tourniquet may be applied immediately to a profusely bleeding limb to allow for rapid movement to safety. The defining factor is the sheer volume and persistence of the blood loss, which can lead to hypovolemic shock within minutes.
Proper Application Technique
Selecting the correct device is key, as commercially manufactured windlass-style tourniquets are more effective than improvised versions, which can fail to generate sufficient pressure. Once chosen, the tourniquet must be placed directly on the skin, if possible, or over clothing that does not contain hard objects. The device should be positioned high on the limb, about two to three inches above the wound, ensuring it is placed between the injury and the torso.
The tourniquet is tightened by pulling the strap as firmly as possible before engaging the windlass rod. The rod is then twisted multiple times until the blood flow from the wound completely ceases. Correct application is confirmed when the bleeding stops and there is no palpable pulse felt below the tourniquet. Finally, the windlass rod must be secured in its clip or holder to prevent it from unwinding, locking the pressure in place.
Situations Where Alternative Methods Are Necessary
A tourniquet is designed only for injuries to the extremities and should never be used for bleeding on the torso, neck, or head. These areas lack the underlying bone structure necessary to compress the major vessels against, making the application ineffective and potentially causing severe injury to soft tissues. Direct, firm pressure remains the gold standard for controlling most external bleeding, including minor injuries that do not pose an immediate threat of death.
Using a tourniquet for minor bleeding is inappropriate because the device completely stops arterial blood flow to the rest of the limb. This interruption of circulation, known as ischemia, can lead to tissue and nerve damage if sustained for too long. Therefore, if the hemorrhage can be easily managed by applying continuous pressure with a clean cloth or dressing, the application of a tourniquet should be avoided entirely. The risk of limb damage from a necessary tourniquet is always secondary to the risk of death from uncontrolled hemorrhage.
Immediate Steps Following Application
Once a tourniquet is applied and severe bleeding stops, immediate action must focus on communicating the intervention and ensuring rapid medical transport. It is mandatory to note the exact time the tourniquet was applied and make this information clearly visible to emergency responders, often by writing it directly on the device or the patient’s forehead. This timestamp is vital for medical personnel to manage the risk of tissue damage.
Emergency medical services must be contacted immediately, if not already done, and the patient should be monitored for signs of shock until professional help arrives. The tourniquet should never be loosened or removed by an untrained person, even if the patient expresses extreme pain. Only qualified medical professionals can make the decision to convert the device to an alternative pressure dressing under controlled conditions.