A tourniquet is a medical device designed to apply pressure to a limb, stopping blood flow to control severe bleeding. Its primary purpose is to prevent life-threatening blood loss in emergency situations. It acts as a temporary measure until professional medical help is available.
When to Use a Tourniquet
A tourniquet is indicated for severe, uncontrollable bleeding from an arm or leg that direct pressure alone cannot stop. This includes situations where blood is spurting, soaking through bandages rapidly, or when direct pressure is impractical due to multiple injuries or a hazardous environment. Conditions such as arterial bleeding, traumatic amputations, or significant crush injuries often necessitate immediate tourniquet application. These injuries can lead to rapid blood loss and hypovolemic shock.
Tourniquets are also used in scenarios like gunshot wounds or stab wounds to an extremity where internal damage makes direct pressure insufficient. In mass casualty events, a tourniquet can be applied quickly to control hemorrhage, allowing first responders to stabilize multiple patients efficiently. A tourniquet provides a more consistent and sustainable method of bleeding control, freeing up hands for other interventions or patient transport.
Circumstances for Caution or Alternative Methods
While effective for severe limb bleeding, tourniquets are not always the first choice. Direct pressure remains the initial and most common method for controlling bleeding, as it is sufficient in most cases. A tourniquet should only be applied if direct pressure, applied for at least 15 minutes, fails to stop or significantly reduce the bleeding. Using a tourniquet unnecessarily can cause tissue damage and complications.
Tourniquets are designed for limb injuries and are not suitable for bleeding from the head, neck, or torso, as this is ineffective and can cause harm. Caution is advised for certain patient conditions, such as severe peripheral vascular disease, sickle cell disease, or a history of deep vein thrombosis in the affected limb. Improvised tourniquets made from thin materials like shoelaces or cords are often ineffective and can cause more injury than benefit, potentially cutting into tissue or failing to stop blood flow.
Applying a Tourniquet Correctly
Correct tourniquet application is crucial for effectiveness and minimizing harm. The tourniquet should be placed high on the injured limb, typically 2 to 3 inches above the wound, between the injury and the heart. It should never be placed directly over a joint, such as an elbow or knee, as this can prevent effective compression and cause nerve or joint damage. If possible, apply the tourniquet to bare skin, but it can be placed over clothing if necessary, though this might increase the chance of slippage.
The device must be tightened sufficiently to completely stop bleeding, indicating arterial blood flow occlusion. This often involves twisting a windlass rod until bleeding ceases and no pulse can be felt below the tourniquet. This process can be painful for the injured person, but the pain is a necessary indicator of effective application. Once tightened, the rod should be secured to prevent it from unwinding.
Immediate Actions After Tourniquet Application
Once a tourniquet has been applied and bleeding is controlled, immediate actions are important for patient care. The first priority is to call for emergency medical services without delay. It is important to note the exact time the tourniquet was applied, as this information is important for medical professionals assessing the patient. This time should be clearly written on the tourniquet itself or on the patient’s forehead.
The tourniquet should remain visible and not be covered by clothing or bandages. Avoid loosening or removing the tourniquet once applied, as this can lead to a dangerous surge of blood flow back to the injured area and resumption of severe bleeding. Only trained medical professionals should remove a tourniquet in a controlled hospital environment. The injured individual requires prompt transport to a medical facility for definitive treatment and evaluation of the limb.