A tourniquet is a device designed to apply circumferential pressure to an arm or leg to stop severe, life-threatening bleeding. It is a temporary measure that restricts blood flow to the injured limb until professional medical help arrives. While direct pressure is the preferred initial method for most bleeding wounds, a tourniquet is used when bleeding cannot be controlled by other means. Severe trauma can cause a person to bleed out in just a few minutes, making the rapid and correct application of this device critical.
Recognizing When a Tourniquet is Necessary
A tourniquet should be used exclusively for life-threatening bleeding from an extremity that cannot be stopped by applying direct pressure. This uncontrolled bleeding often appears as blood actively spurting from the wound or pooling rapidly on the ground. Injuries commonly requiring a tourniquet include complete or partial amputations, severe crush injuries, and deep penetrative wounds like those from gunshots or stabbings.
A tourniquet is necessary if direct pressure is ineffective after several minutes. It is also the appropriate choice when the environment prevents safe access to the wound for continuous direct pressure, such as in a mass casualty event or an unsafe scene. It is a necessary intervention when the alternative is death from exsanguination.
Precise Anatomical Placement on the Arm
The location for applying a tourniquet on the arm is guided by the principle of rapidly compressing the main artery against the underlying bone to halt blood flow. For non-medical personnel, the consensus is to apply the device “high and tight” on the upper arm, meaning as high up on the limb as possible, near the armpit. This placement is recommended because it is fast, effective for all upper arm injuries, and ensures the tourniquet is above any hidden wounds.
A more precise placement, if time permits, is about two to three inches above the wound itself, but never directly over a joint like the elbow. This slightly lower placement can help preserve healthy tissue by limiting the area without blood flow. The upper arm is an effective site because the humerus, a single bone, allows the tourniquet to effectively compress the brachial artery against it.
Placing a tourniquet over the elbow joint or on the forearm is discouraged. Joints do not allow for the consistent, firm compression needed to stop arterial flow, making the device ineffective. While research indicates a tourniquet can be effective on the forearm, the upper arm location is still preferred for rapid and guaranteed occlusion.
Essential Steps After Tourniquet Application
Securing the Device
Once the tourniquet is secured on the arm, ensure the bleeding has completely stopped. The windlass rod must be twisted until the flow of blood ceases and the pulse below the device is no longer detectable. After achieving control, the windlass must be secured in its clip or holder to prevent it from unwinding and losing tension.
Time Marking and Transport
A critically important action is to note the exact time the tourniquet was applied. This time must be clearly marked on the device itself or on the person’s forehead, as medical professionals need this information to manage the risk of tissue damage. The goal is to transport the person to a hospital where the tourniquet can be removed or converted to a pressure dressing ideally within two hours.
Post-Application Care
Once applied and secured, the tourniquet must not be covered by clothing or bandages. No one should attempt to loosen or remove it, as this can cause a sudden rush of blood back into the limb or restart the hemorrhage. Immediately call for emergency medical services and stay with the injured person until they arrive.