A pressure dressing is a specialized first-aid technique used to control severe, life-threatening bleeding (hemorrhage). This type of bandage is engineered to apply continuous, direct, and firm force to a wound site for a prolonged period. Unlike a simple adhesive bandage, a pressure dressing is designed for serious injuries where standard manual pressure alone has proven insufficient to stop the flow of blood. Its application is considered an intermediate measure in hemorrhage control, bridging the gap between basic dressing and the use of a tourniquet for extremity injuries. Its primary purpose is to stabilize the patient and minimize blood loss while awaiting professional medical care.
The Purpose and Function of a Pressure Dressing
The objective of a pressure dressing is to control hemorrhage by assisting the body’s natural clotting process. When a blood vessel is damaged, the physiological response (hemostasis) involves vascular spasm, platelet plug formation, and coagulation to create a stable fibrin clot. Applying sustained external pressure physically compresses the injured blood vessels, slowing the rate of blood loss from the site.
This mechanical compression minimizes the outward flow of blood, giving the body’s clotting factors and platelets the time they need to aggregate and form a stable clot. Since the dressing frees the hands of the first responder, it allows consistent pressure to be applied over a long period, which is often more effective than manual pressure alone. Pressure dressings are particularly useful for wounds on the trunk or head where a tourniquet cannot be applied, or for bleeding that continues to soak through initial bandages. This control is achieved without completely cutting off circulation to the limb beyond the injury, a key difference from a tourniquet.
Essential Materials and Application Technique
Materials
Creating an effective pressure dressing requires three main components: a sterile primary dressing, a bulky pressure pad, and a strong wrapping material. The process begins by applying a clean or sterile, non-adhesive pad directly over the wound to cover the entire injury site. If there are any impaled objects, they must be stabilized in place with material before covering the wound and should never be removed.
Application
Next, a bulky material, such as rolled gauze, a clean cloth, or a dedicated pressure bar, must be placed directly on top of the primary dressing and centered over the point of most severe bleeding. This pad focuses the compressive force needed to restrict the damaged vessel. The final step involves securing this entire assembly with a strong, elastic wrapping material, such as an elastic bandage or roller gauze, wrapped tightly around the limb or body part.
The wrapping should extend a few inches above and below the wound to distribute the pressure evenly and prevent the dressing from shifting. The wrap must be applied with enough tension to firmly compress the pressure pad into the wound, but not so tight that it completely stops all blood flow below the injury. If blood soaks through the dressing, do not remove the assembly; instead, add a new pad on top of the saturated one, and apply a new, tighter outer wrap.
Monitoring and Recognizing Complications
After applying the pressure dressing, continuous monitoring of the patient and the injured limb is necessary to ensure effectiveness and safety. An effective application is indicated when the bleeding slows significantly or stops entirely, and the dressing remains securely in place. The injured person should be observed for signs of excessive blood loss, such as a drop in blood pressure or a rapid heart rate.
A significant risk of an overly tight pressure dressing is that it can act like a tourniquet and compromise the circulation distal to the wound. Signs of excessive pressure include numbness, tingling, or a pale or bluish discoloration (cyanosis) of the skin, fingernails, or toenails below the dressing. The absence of a pulse below the dressing is a clear indication that the wrap is too tight and is dangerously impeding blood flow.
If signs of compromised circulation are noted, the outermost layer of the dressing must be slightly loosened until circulation returns. This is indicated when the skin color becomes normal and the pulse is detectable again. The inner pads should never be removed, as this could disrupt the forming clot and restart severe bleeding. Professional medical attention is always required immediately following the application, even if the bleeding appears controlled.