Skin Failure: A Quest for a Universal Definition

For years, the wound care community has struggled to create a clear definition and diagnostic criteria for skin failure. In 2 recently published articles in Wounds,¹^,² the authors share their struggles.

Hill and Peterson,¹ Bain et al,² and Levine³ address the lack of validated assessment tools, pathophysiology, and a clear definition of skin failure, especially at the end of life.

Dermatologists Inamadar and Palit⁴ define skin failure as a “state of total dysfunction of the skin resulting from different dermatological conditions. It is manifested by a loss of normal temperature control with the inability to maintain core body temperature, failure to prevent percutaneous loss of fluid, electrolytes, and protein, resulting imbalance, and failure of the mechanical barrier to prevent penetration of foreign materials.” To Inamadar and Palit,⁴ skin failure is a dermatological emergency and requires a multidisciplinary approach. The working definition of skin failure by Levine³ is “the state in which tissue tolerance is so compromised that cells can no longer survive in zones of physiological impairment that includes hypoxia, local mechanical stresses, impaired delivery of nutrients and a buildup of toxic metabolic byproducts.” Per Levine, skin failure includes pressure injuries that occur at life’s end, and in the setting of multi-system organ failure.

The 2 definitions are quite different. The dermatologic definition attributes skin failure to specific dermatologic conditions implying “diffuse” failure of the skin. The wound care definition emphasizes the lack of tissue tolerance; in other words, the skin becomes extremely susceptible to outside forces such as hypoperfusion and pressure.⁵ A very high percentage of wounds seen by wound care specialists, including end-of-life wounds, are located primarily over bony prominences. The Kennedy Terminal Ulcer is described as occurring over the sacrum and coccyx. Skin Changes at Life’s End (SCALE) occur mostly over mostly over bony prominences. This begs the question—are these occurences end-of-life “skin failure” or, in fact, are they pressure injuries?

Is it possible to develop a definition and diagnostic criteria universally acceptable to dermatologists and wound care professionals? Should a clinician be able to examine documentation and skin changes and distinguish actual skin failure from a pressure injury? One way to approach this dilemma is to go to the dermatologic literature, which contains examples of diagnostic criteria and physical signs for specific types of skin failure.⁶

How can the interprofessional medical community develop a single definition of skin failure?

Let us start with a possible definition proposed by this letter’s author:

True skin failure is a condition in which the skin may show discreet and/or diffuse areas of clinically visible changes such as necrosis, desquamation, bullae, and hemorrhagic changes with no relation to pressure, shear, or other noxious forces. In most cases, skin failure is not confined to one skin area or related to bony prominences. There can be multiple etiologies such as bacterial, allergic, thrombotic, or idiopathic.

In terms of pressure injuries, including end-of-life injuries, it is also essential to establish clinical criteria. When diagnosing end-of-life wounds as pressure injuries vs skin failure, the supporting documentation of implemented preventive measures must be valid. For example, can one say with certainty that an end-of-life wound came about spontaneously, or was it due to the lack of pressure relief? In the eyes of the present author, skin failure is a rare event. Until a universal definition can be agreed upon, too many wounds that are in fact pressure injuries are being labeled or attributed to skin failure, complicating the question of whether wounds are unavoidable.

To that end, it is imperative that experts from the dermatologic and wound care communities come together to establish universal diagnostic criteria and universally acceptable definitions for skin failure and pressure injuries. I believe it is an achievable goal.

Sincerely,
Kenneth Olshansky, MD

Affiliation: Virginia Commonwealth University/Medical College of Virginia, Richmond, VA

Correspondence: Olshanskyken@gmail.com

Disclosure: The author discloses no financial or other conflicts of interest.