How To Handle Black Eschar Formation
Many leading researchers and wound care practitioners have shown that one of the most important elements in treating wounds is performing regular debridement of tissue (such as eschar) which interferes with wound healing. Timothy Shea, DPM, says the standard approach is to initially debride eschar (and other non-viable tissue) until you get down to good viable tissue and do subsequent debridement every seven to 10 days until you see good granulation tissue.
But what about the presence of black eschar? According to Alexander Reyzelman, DPM, there is a bit of controversy over whether you should debride black eschar or leave it alone. Dr. Shea notes that eschar formation is more problematic when you’re treating patients who have underlying diseases (i.e. diabetes, immunological deficiencies) or have conditions (arterial or venous disease) which inhibit the normal phases of wound healing.
“In these wounds, the inflammatory process is delayed, leading to a buildup of eschar, which then interferes with the proliferative phase and leads to the creation of a chronic wound,” explains Dr. Shea.
With these issues in mind, our expert panelists discuss what goes into their decision-making when determining how to handle black eschar.
Q: Does the location of the eschar alter your decision to debride?
A: Dr. Shea says it is important to consider the location of the wound as it relates to underlying tissue, such as subcutaneous fat, ligaments, tendons and bone. If you are going to be debriding areas such as the heel or under the metatarsals, Dr. Shea says it is common to debride as far as bone and remove some of the bone as well.
“The important factor to remember here is to be more aggressive than conservative,” he advises. “If you are not aggressive enough, you will leave behind non-viable tissue and will eventually have to go back in and remove it later.”
While location does not play as big a role as the clinical appearance and cause of the eschar in their decision-making, Dr. Reyzelman and Suhad Hadi, DPM, say they are more “cautious” about heel eschars. Once the heel develops an eschar, Dr. Reyzelman points out that there is not much protecting the calcaneus except the avascular subcutaneous fat and fascia. He warns that heel ulcerations and eschars “frequently” lead to partial/total calcanectomies or a proximal leg amputation.
Dr. Hadi adds that when eschar is solely caused by an area of pressure (such as a heel pressure ulcer), it is strictly due to focal pressure necrosis. She says you can often offload these areas and the eschar will slough in time, leaving behind an epithelialized region, which avoids the creation of an ulcer.
However, when the eschar is related to a degree of vascular compromise (based upon your clinical findings), Dr. Hadi emphasizes leaving the eschar alone. In order to test eschar and its relation to vascular compromise, Dr. Hadi recommends debriding the periphery of the eschar to visible wound margins and following the patient within a week. If there is associated vascular compromise, Dr. Hadi says you will see the eschar reform. If there is no vascular compromise, you’ll see epithelialization of the debrided region.
If the eschar is freely mobile, loose, separates from the underlying tissue, has a foul odor or purulent exudates, Drs. Reyzelman and Hadi say you should suspect an underlying infection and proceed to immediately debride the eschar. If you see that the eschar has a “wet and soupy” presentation, Dr. Reyzelman recommends immediate debridement.
However, if your patient has dry black eschar that is well adhered to the underlying subcutaneous tissue, you should leave the eschar alone, according to Dr. Reyzelman. With time, he says you’ll see the edges of the eschar begin to lift away from the newly formed epithelial tissue. At this time, you can debride the loose edges while leaving the rest of the eschar alone. He emphasizes that dry black eschar implies a “significant component of peripheral arterial occlusive disease” and may necessitate further arterial workup. Debriding these eschars will expose subcutaneous fat, which increases the risk of desiccation and the development of deep infection, points out Dr. Reyzelman.