Wound debridement and dressing

Overview of wound debridement and dressing

Ulcers and wounds are very common in two categories of people- professional athletes and bed-ridden patients. The statistics of the Center for Disease Control and Prevention (CDC) show that around 3.5 million sports injuries are reported per year. CDC also reports that nearly 5-10% of the global population suffer from ulcers at some point in time. In either case, proper treatment and healing of the wounds is necessary. Debridement and dressing are the two popular techniques that are employed to facilitate a speedy recovery. This article will discuss both the methods and explain its effectiveness in various cases.

Wound debridement

Wound debridement is defined as the scientific removal of the damaged, infected or dead tissues from the site of injury in order to facilitate speedy recovery and healing of the remaining healthy tissues as well as the affected tissues.

The effectiveness of the debridement technique determines the healing potential of the damaged tissues.

Different methods such as chemical, mechanical, surgical, autolytic and maggot therapy are utilized in the process of wound debridement.

In certain serious cases, the boundaries of the damaged tissues are not discernable. In such cases, a portion of the healthy tissues is also removed in order to make sure that residues of the infected tissues are not present.

Types of wound debridement

Based on the mechanism involved, wound debridement is categorized into the following types-

• Autolytic Debridement

This method utilizes autolysis, which is a technique of destruction of cells and is often called self-digestion. It is the process of complete destruction of a cell with the help of its very own enzymes. This method utilizes the body’s own enzymes and moisture to re-hydrate, soften and melt the slough or the eschar (rough coating on a wound surface). 

This method is not applicable to all kinds of damaged tissues. Only the necrotic tissues can be liquefied and removed in this manner. Therefore autolytic debridement is selective in nature. The main advantage of this process is that it is absolutely painless. The most recommended technique of autolytic debridement is the use of occlusive or semi-occlusive dressings. This helps maintain the wound fluid that is in contact with the necrotic tissues.

The commonly used materials for autolytic debridement are- hydrogels, hydrocolloids, and transparent films. This method of debridement is most effective for Stage III or Stage IV wounds where mild to moderate exudates are released.

• Enzymatic Debridement

This method involves chemical enzymes that eat off or peel off the necrotic tissues. These enzymes are mainly derived from microbes like histolyticum and Clostridium. Plants like Papain, Bromelain, Varidase, and Collagenase can also act as sources of these enzymes. Few of these enzymes are selective, while the rest are non-selective. 

This technique is best employed for wounds, especially burns having a large concentration of necrotic debris or eschar formation. In this technique, however, complete and speedy recovery is not always guaranteed. Therefore the doctors do not regard this technique as a standard debridement method for wound treatment.

• Mechanical debridement

Hydrotherapy is commonly used in this technique. This helps in selective mechanical debridement, wherein a tissue is removed for the treatment of wounds. The popular means of mechanical debridement are- directed wound irrigation and mechanical irrigation. 

Whirlpool water baths should be avoided for the hydrotherapy because a selective tissue cannot be targeted and the healthy tissues may be damaged in the process.

Non-selective mechanical debridement involves drying up of a moist dressing, followed by removal of the dressing. Mechanical debridement turns out to be most effective for wounds with dead tissues (necrotic debris).

• Surgical debridement

It is the fastest method of wound debridement, though somewhat costly. It is normally carried out under the effect of anesthesia and has two types- laser debridement and sharp debridement. These techniques are very selective, and the level of selectivity depends on the skill and the control of the person handling the instruments. This makes sure that only the selected tissues are uprooted and the rest is left untouched. After the completion of the process, normal blood circulation and the viability of the tissues are revived.

• Maggot therapy

Maggots are microscopic creatures that feed on dead and decayed tissues. In this therapy, a number of maggots are incorporated into to the site of the wound, after which they start feeding on the necrotic tissues in a manner more selective than the surgical procedures. The healthy tissues are left intact. The process gets completed in 3-4 days.

Wound dressing

Wound dressing is the process of applying a sterile pad or a compress that is applied to the wound to accelerate the healing process and also protect the wound from further infections. In this regard, it is necessary to understand the differences between dressing and bandage. While a dressing is placed directly in contact with the wound, a bandage is used as a support to the dressing. A bandage basically attaches the dressing firmly to the wound. To eliminate the troubles of using bandages along with the dressings every time, the dressings these days usually have adhesives.

What are the main objectives of wound dressing?

The primary purposes of wound dressing are:

• Stem bleeding: It helps seal the wound and accelerates blood coagulation.
• Protection: It protects the wound from germs and mechanical trauma.
• Fluid absorption: It helps in the absorption of the exudates (blood and plasma released from the wounds) and prevents skin maceration.
• Pain reduction: The analgesic effect helps lessen the pain to some extent.
• Debridement: It removes slough and infectious tissues from the wound to enable speedy healing

Type of wound dressing

Wound dressing is typically classified into the following types-

• Gauze Dressings
• Biologics
• Skin substitutes
• Scaffolds
• Bio-membranes
• Hydrocolloid dressing
• Foam dressing
• Film / composite dressing
• Stretch gauze/stretch net

Important points to remember

Surgical wounds, which have been sutured properly just after the surgery usually don’t require much dressing.  There are few important measures that need to be taken with dressing and debriding wounds in order to prevent infections:

• The site of the wound should have an apt level of moisture. Too wet or too dry wounds can lead to exacerbation of the wound.
• The wound should be kept free from environmental toxins, including the ones that could contaminate the dressing components.
• The optimum temperature for wound healing is 37 deg C, which is the normal body temperature.
• Unnecessary wound dressing should be avoided.
• Just like moisture and temperature, the pH level should also be maintained at right levels to facilitate proper wound healing.

References