Overview of Wound Debridement
Preparing the bed of a chronic wound to promote skin growth and healing has been a part of wound care for over ten years. There are four key steps to this process, often remembered by the acronym DIME:
* D: Debridement, which means removal of dead tissue from the wound.
* I: Managing Inflammation and Infection in the wound.
* M: Keeping the right Moisture balance in the wound.
* E: Evaluating the Environment of the wound and how well new skin (Epithelialization) is growing.
The DIME approach is a comprehensive method used worldwide for managing chronic wounds, from which a more detailed healing plan can be developed.
The main aim of debridement is to get rid of all the dead or dying tissue from the wound to encourage healing. Debridement also helps in removing biofilm (a group of microorganisms sticking to each other on the wound surface), bioburden (the number of bacteria living on the wound that the body can tolerate without causing an infection), and senescent cells (old cells that no longer divide). It is recommended to do this at every medical check-up.
Anatomy and Physiology of Wound Debridement
Your skin is made up of two primary layers – the epidermis and the dermis. The epidermis, the topmost layer, is made of tightly packed skin cells. The next layer, the dermis, is a thick layer made up of a type of tissue known as irregular connective tissue. Inside this layer, you’ll find important elements such as blood vessels, hair roots, and sweat glands.
Underneath the dermis is a layer called the hypodermis. This layer is made up mostly of a type of loose tissue and fat. Beneath this layer, you will find muscles, tendons which connect muscle to bone, ligaments that connect bones to each other, bones themselves, and cartilages – a flexible connective tissue found in many areas in the body.
The cells in the epidermis are filled with a protein called keratin and are arranged in layers. The dermis not only contains blood and lymph vessels, which are small tubes that carry fluids around the body, and nerves, but it also holds other important structures like the roots of your hair and the glands that produce sweat.
Why do People Need Wound Debridement
Debridement is a medical procedure used to clean a wound by removing dead or damaged tissue, skin, and other unwanted materials like bacteria and dirt that might prevent the wound from healing properly. This process is common in wound care and helps the wound to heal by exposing the healthy tissue underneath. Damaged or dead tissue can be a source of food for bacteria and can form a barrier that stops the wound from healing.
Dead tissue can also get in the way of medication that is put onto the wound, stopping the medicine from reaching the parts of the wound that need it. Furthermore, it can prevent the growth of new blood vessels and skin over the wound and the normal building of the tissue that provides support to cells. The presence of dead or damaged tissue can also make it hard for doctors to see how deep or severe the wound is and can hide signs of infection.
Here are some common reasons why a doctor might use debridement:
- To remove dead tissue that might be causing infection
- To clean a local infection to decrease the number of bacteria, reduce the chance of antibiotic resistance, and to get accurate samples for testing
- To collect samples for testing after debridement from the healthy tissue left to check for any remaining infection and to determine the necessity for further antibiotic treatment
- To support wound healing and prepare the wound for treatment involving a skin graft or flap, a surgical procedure that involves using skin from another part of the body to cover the wound
When a Person Should Avoid Wound Debridement
There are certain situations where wound debridement, a process that removes damaged tissue to help a wound heal, might not be safe. For example, it might not be recommended when there are dry and intact scars, called eschars, without any signs of infections underneath. These could be in situations like an unstageable pressure ulcer (a type of wound from pressure) that has an intact eschar at places such as the base of the spine (sacrum) or the buttock, or the heel.
There are also other situations where debridement might not be safe and these typically depend on the specific method of debridement being used.
How is Wound Debridement performed
Different types of cleaning processes can remove damaged tissue effectively from wounds. These include surgical cleaning, biological cleaning, enzymatic cleaning, and autolytic cleaning.
Autolytic Cleaning
This is the most common type of tissue-cleaning. It’s a natural process where the body’s cells and proteins break down the damaged tissue. This process only affects dead tissue in the wound.
This cleaning process is suitable for wounds that are not infected. Also, it can complement therapy for infected wounds. It can be combined with other cleaning techniques in the case of infected wounds.
This type of cleaning does require a moist environment and a functioning immune system to help fight off any potential infections. The use of dressings that retain moisture can aid this cleaning process. It softens the dead tissue, which makes it easier to separate from the rest of the wound.
This cleaning process can take a few days. If the amount of dead tissue does not reduce significantly in one or two days, a different cleaning method might be necessary.
Biological Cleaning
This type of cleaning, also known as larval therapy, uses sterile larvae of a type of green bottle fly. It’s an effective way of cleaning large wounds where painless removal of dead tissue is needed. The larvae release enzymes containing secretions and waste that break down dead tissue in the wound. The larvae also help by:
1. Eating and breaking down bacteria
2. Inhibiting the growth of bacteria by producing and releasing ammonia into the wound, which increases the wound’s pH level.
3. Breaking down existing biofilm in the wound bed and preventing new biofilm growth
4. Direct consumption of dead tissue.[18]
The maggots can be applied directly to the wound bed. They can be enclosed in a biological bag or allowed to roam freely.
Research has shown that maggots that roam freely can clean a wound at least twice as fast as bag-confined maggots.
Enzymatic Cleaning
This is a selective method for cleaning damaged tissue. It uses a protein-digesting enzyme, collagenase, to get rid of harmful bacteria. It’s a slow process, but the use of collagenase and moisture-retaining dressings can increase its effectiveness.
Collagenase should not be used in severely infected wounds. Furthermore, collagenase should not be used together with silver-based products or Dakin solution.
Surgical Cleaning with Sharp Instruments
This type of cleaning involves removing dead or damaged tissue using sharp instruments such as a scalpel. This can be done at the bedside, in the doctor’s office, wound care centre, or the operating room, depending on the patient’s requirements and the ability to control potential complications, like bleeding.
Surgical cleaning can be used with all the other cleaning methods.
Drawbacks of surgical cleaning include possible complications from the cleaning itself, like bleeding, and potential overall complications from anesthesia. It is contraindicated in patients with an intact eschar (a patch of dead tissue) and no clinical evidence of an underlying infection.
Mechanical Cleaning
Mechanical cleaning is performed using physical force (e.g., wet-to-dry, pulsatile lavage, or wound irrigation) to remove both dead tissue/debris and viable tissue. It is suitable for acute and chronic wounds with a fair amount of dead tissue, regardless of infection.
Mechanical cleaning is not recommended for wounds that contain more healthy (granulation) tissue than dead tissue, and if pain cannot be controlled adequately, in patients with poor blood flow, and in cases where there is an intact eschar without any visible signs of an underlying infection.
Possible Complications of Wound Debridement
If you need to undergo a medical process called debridement, which is the removal of damaged tissue from a wound, you should be aware that it can cause side effects. These vary according to the type of debridement and can go from minor skin irritation to more serious issues like heavy bleeding.
Surgical debridement and mechanical debridement, which both involve manually removing the tissue, can often cause more bleeding and you may experience pain during the procedure.
If surgical debridement needs to be done in an operating room, it’s important to note that there is some risk involved with the anesthesia used. Besides the immediate risks, one study showed that after this procedure the death rate was 2%, and long-term death rate could be as high as 68%.
What Else Should I Know About Wound Debridement?
Cleaning a wound, particularly a deep wound like an ulcer that has dead tissue, is extremely important for quicker and proper healing. This process of removing the dead tissue and other harmful stuff like bacteria is known as ‘debridement’. It is a standard practice in wound management. It is important to know that debridement doesn’t just mean cleaning the wound; it also stimulates the body’s healing powers by encouraging the production of certain growth factors that facilitate the wound’s recovery.
One type of debridement, known as ‘sharp surgical debridement’, even helps reset the sequence of healing stages, essentially helping your body start the healing process as if the wound was fresh. This method has also been proven to stimulate the growth of new blood vessels in the area of the injury, which is an essential part of healing.
Obviously, not all methods of cleaning a wound will have the same effect, as different approaches are necessary depending on the wound. What’s important, though, is that some form of debridement is used to create the conditions necessary for the wound to heal naturally.
That said, there are exceptions. For instance, in a special type of ulcer called an ‘unstageable pressure ulcer’ with no clear sign of infection, debridement is not always the best course of action. For these kinds of ulcers, the dead tissue acts as a natural protective cover and should be left in place.
The approach to cleaning a wound should be chosen according to the specific situation of the wound. Things like the patient’s other health conditions, the alternative safer methods, and the patient’s comfort and preferences all come into play when deciding on the best approach.