The eschar forms when a wound becomes deep and severe, especially if it is deep and severe. Eschar is usually dry, black, and hard, and may stick to the wound bed and edges. As it can interfere with wound healing and increase the risk of infection, it is often recommended to remove it. However, eschar may in some cases act as a natural barrier, protecting the wound.
Eschar can develop on wounds that involve full-thickness injury, which means that the damage extends beyond the epidermis and dermis, the outer and middle layers of the skin. Examples of such wounds include:
Third-degree burns, which destroy all layers of the skin and may affect the underlying tissues, such as muscles, nerves, and bones.
These are wounds that result from prolonged pressure on the skin, especially over bony areas like the heels, hips, or buttocks, which are also known as bedsores or decubitus ulcers. The pressure reduces blood flow to the skin, causing tissue death and ulceration.
Some skin infections, such as ecthyma gangrenosum, scrub typhus, rickettsialpox, and anthrax. These are caused by bacteria or parasites that invade the skin and cause necrosis, inflammation, and ulceration.
As opposed to scabs, which form on the surface of minor wounds, escar is different. Blood clotting factors, such as platelets and fibrin, form a scab, which traps red blood cells and seals the wound. By preventing blood loss and infection, scabs help wounds heal. On the other hand, an escar is composed of dead tissue debris which accumulates on the wound. The formation of new tissue is hindered by escar, rather than helping the wound heal.
In addition to appearing dark, crusty, and leathery, eschar can also be tan, brown, or black, depending on the amount of blood and pigment in the tissue. It can be soft or firm, depending on how moist the wound is. It may cover the entire wound or only some of it.
Eschar may be associated with other symptoms, depending on the type and severity of the wound. These may include:
Pain, swelling, redness, and warmth around the wound
Foul odor and pus from the wound
Fever, chills, and malaise
Signs of infection, such as cellulitis, bacteremia, or sepsis
A visual inspection of the wound can diagnose eschar. According to the extent and depth of tissue damage, the wound may be classified into stages. The wound cannot be staged accurately when eschar is present, because the eschar obscures the wound below. Before the wound can be properly assessed, the eschar must be removed.
Eschar may also require further evaluation to determine the cause and type of the wound. This may involve:
Taking a medical history and performing a physical examination
Taking a wound culture or biopsy to identify the microorganisms or toxins involved
Performing blood tests to check for signs of infection or inflammation
Performing imaging tests, such as X-rays, ultrasound, or MRI, to assess the extent of tissue damage and rule out other conditions
In addition to the cause, location, size, and condition of the wound, as well as the person's overall health and preferences, the treatment for eschar depends on several factors. During treatment, the eschar is removed, wounds are promoted, infections are prevented, and pain and discomfort are reduced.
The removal of eschar is called debridement, and it can be done by various methods, such as:
Surgical debridement, which involves using a scalpel, scissors, or forceps to cut away the eschar. This is usually done under anesthesia and may require hospitalization.
The process of enzymatic debridement involves applying an enzyme to the eschar in order to break down dead tissue and make it easier to remove. This is usually done at home or in an outpatient setting.
A mechanical debridement involves using physical methods, such as wet-to-dry dressings, whirlpool baths, or pulse lavage, to loosen and remove the eschar.
In a controlled environment, such as a hospital or a clinic, sterile maggots are used to eat away dead tissue. The maggots secrete enzymes and antibacterial substances that help clean the wound.
A debridement can be repeated many times, depending on the amount and condition of the eschar. When the eschar is stable, dry, intact, and not infected, or if it is on a heel or an ischemic limb, debridement may not be necessary or advisable. If this happens, the eschar can serve as a natural dressing and protect the wound from further damage. However, the eschar must be monitored closely for signs of infection or deterioration.
It is important to clean and dress the wound after debridement with appropriate materials, such as gauze, hydrogel, foam, or film, to promote wound healing. The dressing should be changed regularly, kept moist, and protected from pressure, friction, and trauma.
Other treatments that may be used to enhance wound healing and prevent complications include:
Antibiotics, either oral or topical, to prevent or treat infection
Analgesics, either oral or topical, to relieve pain and inflammation
Hyperbaric oxygen therapy, which involves breathing pure oxygen in a pressurized chamber, to increase blood flow and oxygen delivery to the wound
Skin grafts or flaps, which involve transplanting healthy skin from another part of the body or a donor, to cover large or deep wounds
Negative pressure wound therapy, which involves applying a vacuum device to the wound, to remove excess fluid and stimulate blood flow and tissue growth
Eschar can be prevented by avoiding or treating the underlying causes of the wound, such as burns, pressure injuries, or infections. Some general measures that can help prevent eschar include:
Keeping the skin clean and dry
Applying moisturizers and sunscreen to the skin
Avoiding exposure to extreme heat or cold
Wearing protective clothing and equipment when handling hot or sharp objects
Changing positions frequently and using cushions or pads to relieve pressure on the skin
Checking the skin regularly for any signs of injury or infection
Seeking medical attention promptly for any wounds or skin problems
Eschar is a serious condition that can affect wound healing and increase the risk of infection and other complications. A health care provider can diagnose and treat eschar based on the individual situation, and determine what course of action is best. Eschar can be prevented by taking good care of the skin and avoiding or treating the wound's causes.
