A pressure bandage (also called a pressure dressing) is a bandage that’s designed to apply pressure to a particular area of the body.
Typically, a pressure bandage has no adhesive and is applied over a wound that’s been covered with an absorbent layer. The absorbent layer may or may not be held in place with an adhesive.
Pressure bandages are used to control bleeding and encourage blood clotting without constricting normal blood circulation. They help:
- minimize swelling
- protect the wound from contamination
- protect the injured area from additional trauma
- prevent heat and fluid loss
Keep reading to learn when and how to apply a pressure bandage as well as precautions.
Doctors often use pressure bandages following surgical procedures. They’re also used by emergency medical responders.
Initial wound treatment
If you or someone you’re with has a deep wound that’s profusely bleeding, you may need to apply a pressure bandage. But first, here are the initial steps you should follow:
- Call for emergency medical help to come to you, or decide how to get the wounded person to emergency medical help.
- If necessary, expose the entire wound by removing any clothing around it. You may have to cut the clothing away. If any clothing is stuck to the wound, work around it.
- Don’t try to wash the wound or remove any objects that have been impaled.
- Apply a dressing over the wound. If you don’t have a first aid kit with sterile, nonstick gauze, use the cleanest, most absorbent cloth you have.
- Fold a 3-foot length of cloth into a ribbon about 4 inches wide and tightly but gently wrap it around the limb, then tie it off with a secure but easily adjustable knot. The knot should be over the nonaffected part of the limb, not over the wound.
- Look for signs that you’ve tied the bandage too tightly. For example, if the injured limb is turning blue or becoming cool, slightly loosen the bandage.
- Elevate the wound above the injured person’s heart. If broken bones are involved, you’ll need to splint the limb before elevating it.
- Use your hand to apply manual pressure to the wound for 5 to 10 minutes.
At this point, the wound should be more stable. However, if you see blood soaking through the bandage or dripping out from underneath it, you need to apply a more effective pressure bandage to prevent excessive blood loss.
Excessive blood loss can result in:
- a drop in blood pressure
- a drop in blood volume
- heart rate or rhythm abnormalities
- a low oxygen saturation
If elevation, gauze, and manual pressure haven’t adequately stopped the bleeding, here are your next steps:
- If the injured person’s wound is stabilized and they’re fully awake, have them drink liquids to help replace blood volume.
- Use strips of cloth, cut from clothing if necessary, to make a pressure bandage.
- Wad up some strips and put them over the wound.
- Wrap a longer piece of cloth around the limb and the wad of strips and tie the ends together. You want the pressure to be enough to stop the bleeding, but not so tight as to act as a tourniquet (completely cut off the blood supply to the area). As a tightness test, you should be able to fit your finger under the knot.
- As an alternative to the steps above, if available, you can also use an elastic pressure bandage, like an ACE wrap, placed over gauze and an underlying absorptive bandage pad.
- Check the injured person’s toes and fingers further beyond the pressure bandage to make sure the bandage isn’t too tight. If they’re not warm and pink, loosen the bandages.
- Check often to make sure bleeding has stopped.
- If you see signs of decreased circulation in the limb (pale or blue, cool, numb), loosen the bandage.
You can also use a pressure bandage to treat venomous snake bites.
According to Queensland Children’s Hospital, applying firm pressure over the blood vessels at the site of the poisonous snake bite can slow the venom from progressing into the bloodstream.
If the pressure bandage is tied too tightly around an extremity, the pressure bandage becomes a tourniquet.
A tourniquet cuts off the blood supply from the arteries. Once that blood supply has been cut off, the tissues separated from oxygen-rich blood flow — such as the nerves, blood vessels, and muscles — can be permanently damaged and result in loss of the limb.
If you’ve applied a pressure bandage, continually check around it to make sure you haven’t tied it too tightly or swelling hasn’t made it too tight, but try to maintain a proper amount of pressure.
For some wounds, a pressure bandage may be used to help control bleeding and better allow the blood to clot over a wound.
It’s important, however, for a pressure bandage not to be too tight, as you don’t want it to halt blood flow from the arteries.
You can also use pressure bandages in the treatment of venomous snake bites to help stop the venom from getting into the bloodstream.