Methods of Debridement

Debridement is the removal of waste (exudate), infectious matter and dead tissue from wounds. Debridement may be done to prepare a wound for the application of specialty healing aids or simply to "restart" and stimulate natural healing. For example, patients who present for wound suturing after healing has begun to take place will need the edges of the wound debrided before they can be joined. Burns and pressure ulcers (bedsores) are other examples of wounds commonly subject to debridement. Choice of debridement methods are based on several factors; gentleness and effectiveness are two considerations.

Biodebridement

• Allowing sterile maggots to access and debride a wound has the advantage of antimicrobial properties produced by the insects that reduce infection (Dryburgh, 2008). Blowfly larvae are commonly used for this purpose, however, previous use of hydrogel dressings is incompatible with biodebridement.

  Animal testing of a type of shrimp, Antartic Krill, have been promising and may offer another option.

Mechanical Debridement

• Sharp debridement with surgical instruments is typically done in emergency situations or when preparing for flap graft procedures. It must be done by physicians or other practitioners licensed and trained in the procedure. Even then, it is imprecise and healthy tissue may accidentally be removed.

  Wet to dry dressings are also nonselective and may remove the products of healing (epithelium) along with debris. A gauze dressing is moistened with sterile normal saline or other fluid and applied to the wound. A dry dressing is placed over the wet dressing. When it is dry, both dressings are removed; exudate and debris stick to the dressing and can be pulled off. This method can be painful for patients.

  Whirlpool or pulsed lavage treatment use moving water to debride wounds. Cross contamination and infection are a concern when using whirlpool baths. Pulsed lavage can be localized and adjusted, depending on the patient's condition. Treatments take 15 to 30 minutes depending on the size and percentage of necrosis (dead tissue) in the wound, and may need to be repeated twice a day.

Chemical Debridement

• The use of enzyme gels and solutions on dead tissue can be a gentle method of debridement for some wounds. Enzymes are specific for components of dead tissue and combinations work best. Proteolytic, fibrinolytic and collegenases are categories of these substances. Their application must be limited to dead tissue, however, because they could injure healthy tissue. The wound should be irrigated with normal saline solution prior to chemical debridement. Antibiotic ointments may be indicated after use; follow manufacturer's directions.

Autolytic Debridement

• Dressings that create a moist environment stimulate endogenous enzymes, proteolytic enzymes and phagocytic cells to detach and digest debris. Hydrogel and hydrocolloid dressings create this moist environment, but must be fitted with care because they can also macerate surrounding healthy tissue. Space in a deep wound must be loosely packed with dressings to prevent the formation of pockets that could become abscesses.

  Foam dressings create a moist environment for moderate wounds; transparent dressings can be used on superficial wounds. Both need to be changed in 3 to 7 days.

  Alginates, made from components of natural seaweeds, absorb up to 20 times their weight in exudate and form a gel in this process (Mosher, 1995). They have properties that stop bleeding, and do not inhibit wound closure. They are typically changed at intervals from 12 hours to 3 days.

Warning

• The decision to debride should be based on the patient's wishes, habits (such as smoking), condition, the placement of the wound and the prognosis for healing. If there is not adequate circulation to heal the wound after it has been debrided, removing dead tissue may make the situation worse. Stable heel ulcers are an example of wounds where debridement would be inappropriate.