Understanding Wound Eschar: Types and Treatment Approaches

What is Eschar?

• Definition: Eschar is a form of necrotic (dead) tissue that forms a dry, thick, often black or brown, leathery or crusty covering over a wound. It is most commonly seen in pressure ulcers, burns, arterial ulcers, and wounds with severe tissue ischemia
• Distinction: Eschar is different from slough, which is softer, moist, yellow or white, and loosely attached. Eschar is typically dry, hard, and firmly adherent, though it can sometimes be softer or lifting at the edges

Types of Eschar

Type	Appearance	Typical Causes	Clinical Notes
Dry, Stable Eschar	Hard, dry, black/brown	Pressure ulcers (especially heels), arterial ulcers	Firmly attached, no drainage or redness; may act as a natural barrier
Unstable Eschar	Wet, boggy, softening, may be draining	Infection, increased bacterial proteolysis	May be associated with redness, edema, fluctuance, odor; higher risk of sepsis
Lifting Eschar	Edges not fully attached	Healing phase or mechanical disruption	May be trimmed if lifting, but assess for underlying infection

 Clinical Significance

• Eschar impedes wound healing by acting as a barrier to epithelial migration and can harbor bacteria, increasing infection risk.
• Eschar can act as a natural barrier for infection prevention (dry/stable).
• The presence of eschar makes accurate wound staging impossible until it is removed or sloughs off, as the true depth and tissue involvement cannot be assessed.

Treatment and Management Strategies

1. Assessment

• Evaluate the wound for signs of infection: redness, warmth, swelling, drainage, odor, and pain
• Assess vascular status, especially in limb wounds, to ensure blood flow is not compromised by circumferential eschar
• Determine if the eschar is stable (dry, intact, no signs of infection) or unstable (wet, draining, infected)

2. When to Remove Eschar

• Remove eschar if:
  • It is unstable (wet, draining, boggy, or infected)
  • There is underlying infection or sepsis risk.
  • It impairs wound assessment or topical treatment application.
  • There is impaired circulation due to circumferential eschar (may require escharotomy)
• Leave eschar intact if:
  • It is dry, stable, adherent, and not infected-especially on the heel, where it can serve as a natural biological cover and barrier to infection

3. Debridement Techniques

• Autolytic Debridement: Use of moisture-retentive dressings (hydrocolloids, hydrogels) to soften and liquefy eschar gradually
• Enzymatic Debridement: Application of topical agents (e.g., collagenase) to chemically break down necrotic tissue
• Mechanical Debridement: Wet-to-dry dressings, irrigation, or gentle scrubbing (less commonly used due to trauma to healthy tissue)
• Sharp/Surgical Debridement: Use of scalpel, scissors, or curette to remove eschar; indicated for extensive, thick, or infected eschar, or when rapid removal is necessary

4. Post-Debridement Care

• Maintain a moist wound environment to promote granulation and epithelialization.
• Protect the wound with appropriate dressings (alginate, foam, hydrocolloid, or antimicrobial as indicated)
• Monitor closely for signs of infection or recurrence of necrosis.
• Address underlying risk factors: optimize nutrition, glycemic control, offloading for pressure injuries, and vascular supply

Special Considerations

• Controversy: Whether to debride all eschar is debated. The decision should be individualized based on wound location, patient comorbidities, infection risk, and overall healing goals
• Preservation in Select Cases: Recent research suggests that preserving stable eschar in small, deep wounds may reduce excessive scarring and contraction by modulating the inflammatory response
• Patient Education: Inform patients about the importance of wound monitoring, signs of infection, and the rationale behind eschar management decisions.

Summary Table: Eschar vs. Slough

Feature	Eschar	Slough
Appearance	Dry, hard, black/brown	Moist, soft, yellow/white
Consistency	Leathery, crusty, firm	Stringy, loose, or adherent
Attachment	Firmly or loosely attached	Usually loosely attached
Composition	Necrotic tissue, fibrin	Dead cells, exudate, debris
Management	Remove if unstable/infected; may leave stable eschar	Remove to promote healing

References:

1. Armstrong, D. G., & Meyr, A. J. (2023). Debridement techniques for wound management. UpToDate. https://www.uptodate.com/contents/debridement-techniques-for-wound-management
2. Bryant, R. A., & Nix, D. P. (2015). Acute & Chronic Wounds: Current Management Concepts (5th ed.). Elsevier.
3. European Wound Management Association (EWMA). (2013). Debridement: An updated overview and clarification of the principal role of debridement. Journal of Wound Care, 22(1), S1–S52. https://doi.org/10.12968/jowc.2013.22.Sup1.S1
4. National Pressure Injury Advisory Panel (NPIAP). (2019). Prevention and Treatment of Pressure Ulcers/Injuries: Clinical Practice Guideline. https://npiap.com/page/Guidelines
5. Wound, Ostomy and Continence Nurses Society (WOCN). (2016). Guideline for Management of Wounds in Patients with Lower-Extremity Arterial Disease (LEAD). https://www.wocn.org/clinical-resources/clinical-guidelines/
6. Steed, D. L., Attinger, C., Colaizzi, T., Crossland, M., Franz, M., Harkless, L., … & Robson, M. (2006). Guidelines for the treatment of diabetic ulcers. Wound Repair and Regeneration, 14(6), 680-692. https://doi.org/10.1111/j.1524-475X.2006.00176.x
7. Vowden, K., & Vowden, P. (2011). The role of debridement in the healing process. Journal of Wound Care, 20(8), 366–375. https://doi.org/10.12968/jowc.2011.20.8.366