What is negative pressure wound therapy or NPWT?

NPWT is a type of therapy to help wounds heal. During the treatment, a device decreases air pressure on the wound. This can help the wound heal more quickly.

The gases in the air around us put pressure on the surface of our bodies. A wound vacuum device (wound vac) removes this pressure over the area of the wound. This can help a wound heal in several ways. It can gently pull fluid from the wound over time. This can reduce swelling and may help clean the wound. It's unclear if it reduces bacteria. NPWT also helps pull the edges of the wound together. And it may stimulate the growth of new tissue that helps the wound close.

NPWT has several parts. A foam or gauze dressing is put directly on the wound. An adhesive film covers and seals the dressing and wound. A drainage tube leads from under the adhesive film and connects to a portable vacuum pump. This pump removes air pressure over the wound, along with any fluids that drain from the wound. It may do this constantly, or in cycles.

The dressing is changed every 24 to 72 hours. During the therapy, you’ll need to carry the portable pump everywhere you go.

Why might I need negative pressure wound therapy (NPWT)?

You might need this therapy for a recent traumatic wound. Or you may need it for a chronic wound. This is a wound that is not healing properly over time. This can happen with wounds linked to diabetes. You may need NPWT if you’ve had a recent skin graft. And you may need it for a large wound. Large wounds often take a longer time to heal.

NPWT may help your wound heal more quickly by:

• Draining excess fluid from the wound

• Keeping your wound moist and warm

• Helping draw together wound edges

• Increasing blood flow to your wound

• Decreasing redness and swelling (inflammation)

NPWT offers some other advantages over other types of wound care. It may decrease your overall discomfort. The dressings usually need changing less often and are easier to keep in place.

What are the risks of negative pressure wound therapy (NPWT)?

NPWT has some rare risks, such as:

• Bleeding (which may be severe)

• Wound infection

• An abnormal connection between the intestinal tract and the skin (enteric fistula)

Proper training in dressing changes can help reduce the risk of these problems. Also, your healthcare provider will carefully evaluate you to make sure you are a good candidate for the therapy. Certain problems can increase your risk of complications and NPWT may not be used, such as:

• Exposed organs or blood vessels

• High risk of bleeding from another health problem

• Wound infection

• Nearby bone infection

• Dead wound tissue

• Cancer tissue

• Fragile skin, such as from aging or longtime use of topical steroids

• Allergy to adhesive

• Very poor blood flow to your wound

• Wounds close to joints that may reopen due to movement

Your healthcare provider will discuss the risks that apply to you. Make sure to talk with your provider about all of your questions and concerns.

How do I get ready for negative pressure wound therapy (NPWT)?

You likely won’t need to do much to get ready for NPWT. In some cases, you may need to wait a while before having this therapy. For example, your healthcare provider may first need to treat an infection in your wound. Dead or damaged tissue may also need to be removed from your wound.

You or a caregiver may need training on how to use NPWT. This is done if you will be able to have your therapy at home. In other cases, you may need to have your therapy in a healthcare facility such as a wound clinic. If you or a caregiver will be doing the therapy, you’ll be trained on how to use the device.

Your healthcare provider will tell you if you need to do anything else to prepare for NPWT.

What happens during negative pressure wound therapy (NPWT)?

A healthcare provider will cover your wound with a foam or gauze wound dressing. An adhesive film will be put over the dressing and wound. This seals the wound. The foam connects to a drainage tube, which leads to a vacuum pump. This pump is portable. When the pump is turned on, it draws fluid through the foam and out the drainage tubing. The pump may run all the time, or it may cycle off and on. Your exact setup will depend on the specific type of wound vacuum system that you use.

How often your dressing is changed depends on your wound. It may be changed daily, or it may be changed more or less often. You or your caregiver may be trained to do this at home. Or it may be done by a visiting healthcare provider. In some cases, it may be done by a healthcare provider in a hospital or other facility (wound clinic). You may need to stay in a care facility if you have a large or severe wound.

Your healthcare provider may prescribe a pain medicine. This is to prevent or reduce pain during the dressing change.

Tell your healthcare provider right away if you have a fever or increased swelling or pain in your wound. Also tell them if there is blood or blood clots in the tubing or collection chamber of the device.

You will likely need to use NPWT for several weeks or months. During the therapy, you’ll need to carry the portable pump everywhere you go. Your provider will carefully keep track of your healing.

During this time, make sure you have good nutrition and get enough rest. This is required for proper wound healing and to prevent infection. Your provider can tell you more about how to ensure your nutrition during this time.

If you smoke, ask for help so you can stop. The toxic substances in cigarette smoke (especially nicotine, carbon monoxide, and hydrogen cyanide) greatly impair your body's ability to heal the wound.

What happens after negative pressure wound therapy (NPWT)?

Follow up with your healthcare provider if you have a health condition that led to your wound, such as diabetes. They can help you prevent future wounds.

Next steps

Before you agree to the test or the procedure, make sure you know:

• The name of the test or procedure

• The reason you are having the test or procedure

• What results to expect and what they mean

• The risks and benefits of the test or procedure

• What the possible side effects or complications are

• When and where you are to have the test or procedure

• Who will do the test or procedure and what that person’s qualifications are

• What would happen if you did not have the test or procedure

• Any alternative tests or procedures to think about

• When and how you will get the results

• Who to call after the test or procedure if you have questions or problems

• How much you will have to pay for the test or procedure