Debridement

Debridement is the medical removal of dead, damaged, or infected tissue to improve the healing potential of the remaining healthy tissue. Removal may be surgical, mechanical, chemical, autolytic (self-digestion), and by maggot therapy, where certain species of live maggots selectively eat only necrotic tissue.

In oral hygiene and dentistry, debridement refers to the removal of plaque and calculus that have accumulated on the teeth. Debridement in this case may be performed using ultrasonic instruments, which fracture the calculus, thereby facilitating its removal, as well as hand tools, including periodontal scaler and curettes, or through the use of chemicals such as hydrogen peroxide.

In podiatry practitioners such as chiropodists, podiatrists and foot health practitioners remove callus, corns, verrucas etc.

Debridement is an important part of the healing process for burns and other serious wounds; it is also used for treating some kinds of snake and spider bites.

Sometimes the boundaries of the problem tissue may not be clearly defined. For example, when excising a tumor, there may be micrometastases along the edges of the tumor that are too small to be detected, and if not removed, could cause a relapse. In such circumstances, a surgeon may opt to debride a portion of the surrounding healthy tissue — as little as possible — to ensure that the tumor is completely removed.

Autolytic debridement
Autolysis uses the body's own enzymes and moisture to re-hydrate, soften and finally liquefy hard eschar and slough. Autolytic debridement is selective; only necrotic tissue is liquefied. It is also virtually painless for the patient. Autolytic debridement can be achieved with the use of occlusive or semi-occlusive dressings which maintain wound fluid in contact with the necrotic tissue. Autolytic debridement can be achieved with hydrocolloids, hydrogels and transparent films. This method works best in stage III or IV wounds with light to moderate exudate.

Enzymatic debridement
Chemical enzymes are fast acting products that produce slough of necrotic tissue. Some enzymatic debriders are selective, while some are not. This method works best on any wound with a large amount of necrotic debris, or with eschar formation

Mechanical debridement
This technique has been used for decades in wound care. Allowing a dressing to proceed from moist to dry, then manually removing the dressing causes a form of non-selective debridement. This method works best on wounds with moderate amounts of necrotic debris

Surgical debridement
Sharp surgical debridement and laser debridement under anesthesia are the fastest methods of debridement. They are very selective, meaning that the person performing the debridement has complete control over which tissue is removed and which is left behind. Surgical debridement can be performed in the operating room or at bedside, depending on the extent of the necrotic material. This method works best on wounds with a large amount of necrotic tissue in conjunction with infected tissue in the wound.

Maggot therapy
In maggot therapy, a number of small maggots are introduced to a wound in order to consume necrotic tissue, and do so far more precisely than is possible in a normal surgical operation. Larvae of the green bottle fly are used, which primarily feed on the necrotic (dead) tissue of the living host without attacking living tissue. Maggots can debride a wound in a day or two. The maggots derive nutrients through a process known as "extracorporeal digestion" by secreting a broad spectrum of proteolytic enzymes that liquefy necrotic tissue, and absorb the semi-liquid result within a few days. In an optimum wound environment maggots molt twice, increasing in length from 1–2 mm to 8–10 mm, and in girth, within a period of 3–4 days by ingesting necrotic tissue, leaving a clean wound free of necrotic tissue when they are removed. When they stay longer or too many are used, healthy tissue is removed as well.