Wound care management update

September 1, 2005

National report — Treating wounds is a delicate mixture of new tools and tried-and-true wound healing basics, according to Mark D.P. Davis, M.D., associate professor of dermatology at the Mayo Clinic in Rochester, Minn.

National report - Treating wounds is a delicate mixture of new tools and tried-and-true wound healing basics, according to Mark D.P. Davis, M.D., associate professor of dermatology at the Mayo Clinic in Rochester, Minn.

Dr. Davis says it is crucial to identify and treat underlying disease before dealing with the wound itself. Also important to wound care are techniques to: debride wounds, treat complicating infections, control edema and maintain a moist environment.

Cleansing criteria

"Most experts accept that debridement is essential to optimum wound healing, and increasing evidence supports this thinking," Dr. Davis reports.

Dr. Davis says a "beefy red base" is ideal, and debridement stimulates "base" granulation tissue and encourages "edge" epithelial tissue to begin initial wound closure.

Surgical debridement, performed with forceps and scissors or scalpel, is for wounds other than arterial ones. It is most commonly done every one or two weeks in an outpatient setting. Patients typically require topical anesthesia, such as topical lidocaine 4 percent on gauze or lidocaine gel applied to the wound for approximately 20 minutes. Extensive debridement is done in the operating room.

Mechanical debridement occurs when the traditional "wet to dry" dressing is pulled off a wound, Dr. Davis says. When the dressing is removed, some of the slough on the wound comes off with it.

Autolytic debridement is the liquefying of necrotic tissue by the body's own fluids. To permit this to occur optimally, dressings that allow for a moist environment are best.

Enzymatic debridement uses a topical enzyme that liquifies necrotic tissue and slough. Dr. Davis urges caution because the enzymes have the potential to liquefy healthy tissue as well.

"I use enzymatic debridement in only a few circumstances and for limited periods of time," he says.

"Maggots are effective in debriding, but patients do not like them," Dr. Davis notes. "They are not available readily in the U.S."

Wound coverage

Dr. Davis compares selecting an appropriate dressing to reaching into a bag of tricks. Several choices exist beyond just the traditional gauze dressing. These include: hydrocolloids, hydrogels, transparent films, collagen, alginates, foams and antimicrobials.

In all cases, a moist - but not wet - environment is best, and patients must learn proper dressing technique and intervals for changing.

In recent years, silver has become a popular and effective antimicrobial metal added to dressings.

In carefully chosen circumstances, skin grafts and tissue-engineered skin substitutes are advanced wound coverage options.

Edema control

Although it is sometimes neglected, "controlling edema is essential to wound healing," he notes.

Most commonly occurring in the leg, edema can be controlled through leg elevation, use of low-stretch or elastic wraps (ACE wraps) or ankle compression stockings of 30 to 40 mmHg. In select cases, pneumatic compression boots are appropriate. Boots that synchronize with the cardiac cycle may sometimes be used even if arterial supply to the leg is impaired.

Wound closure

The new vacuum-assisted closure (VAC) is a negative pressure system to close open wounds, akin to a vacuum placed on the wound. It is said to increase blood perfusion by removing excess fluid and accelerate nutrient delivery by increasing blood flow.

"While some evidence supports its use, further trials are necessary to ascertain its place in wound healing," Dr. Davis suggests.