Debridement is the process of removing dead tissue from pressure ulcers, burns, and other wounds, to speed healing.
Wounds that contain non-living tissue take longer to heal. This tissue may become colonized with bacteria, producing an unpleasant odor. Though the woundis not necessarily infected, the bacteria can cause inflammation and strain the body's ability to fight infection. Necrotic tissue may also hide pockets of pus called abscesses, which can develop into a general infection that may in turn lead to amputation or death.
Not all wounds need debridement. Sometimes it is better to leave a hardened crust of dead tissue, than to remove it and create an open wound, particularlyif the crust is stable and the wound is not inflamed. Before performing debridement, the physician will take a medical history with attention to factorsthat might complicate healing, such as medications being taken and smoking. Some ulcers and other wounds occur in places where blood flow is impaired. In such cases, the physician or nurse may decide not to debride the woundbecause blood flow may be insufficient for proper healing.
The four major debridement techniques are surgical, mechanical, chemical, andautolytic.
Surgical debridement uses a scalpel, scissors, or other instrument to cut dead tissue from a wound. It is the quickest and most efficient method, and is preferred if there is rapidly developing inflammation of the body's connectivetissues (cellulitis) or a more generalized infection (sepsis)that has entered the bloodstream.
The physician will begin by flushing the area with a saline (salt water) solution, and then will apply a topical anesthetic gel to the edges of the woundto minimize pain. Using forceps to grip the dead tissue, the physician will cut it away bit by bit with a scalpel or scissors. Sometimes it is necessary to leave some dead tissue behind rather than disturb living tissue.
In mechanical debridement, a saline-moistened dressing is allowed to dry overnight and adhere to the dead tissue. When the dressing is removed, the dead tissue is pulled away too. This process is one of the oldest methods of debridement. It can be very painful because the dressing can adhere to living as well as nonliving tissue. Because mechanical debridement cannot select betweengood and bad tissue, it is unacceptable for clean wounds where a new layer ofhealing cells is already developing.
Chemical debridement makes use of certain enzymes and other compounds to dissolve necrotic tissue. It is more selective than mechanical debridement. The body makes its own enzyme, collagenase, to break down collagen, one of the major building blocks of skin. A pharmaceutical version of collagenase is available and is highly effective as a debridement agent. As with other debridementtechniques, the area first is flushed with saline. Any crust of dead tissueis etched in a cross-hatched pattern to allow the enzyme to penetrate. A topical antibiotic is also applied to prevent introducing infection into the bloodstream. A moist dressing is then placed over the wound.
Autolytic debridement takes advantage of the body's own ability to dissolve dead tissue. The key to the technique is keeping the wound moist, which can beaccomplished with a variety of dressings. These dressings help to trap woundfluid that contains growth factors, enzymes, and immune cells that promote wound healing. Autolytic debridement is more selective than any other debridement method, but it also takes the longest to work. It is inappropriate for wounds that have become infected.
Risks of debridement include the possibility that underlying tendons, blood vessels, or other structures will be damaged during the examination of the wound or during surgical debridement. Surface bacteria may also be introduced deeper into the body, causing infection.
Although debridement procedures cause some pain, they are generally well tolerated by patients. It is not uncommon to debride a wound again in a subsequent session.