Advances in wound care science and knowledge occur every day. In February 2007, the National Pressure Ulcer Advisory Panel (NPUAP), via a consensus conference, developed new definitions related to pressure ulcers and staging. Previously, a pressure ulcer was defined as an area “of localized tissue destruction caused by the compression of soft tissue over a bony prominence and an external surface for a prolonged period of time.”1 Now, a pressure ulcer is defined as:
…localized injury to the skin and/or underlying tissue usually over a bony prominence, as a result of pressure, or pressure in combination with shear and/or friction. A number of contributing or confounding factors are also associated with pressure ulcers; the significance of these factors is yet to be elucidated. 2
To elaborate, this new definition states that underlying tissue (such as muscle or adipose tissue), not just epidermis and dermis, can be affected by the forces that contribute to pressure ulcer development. It also incorporates the other mechanical forces (shear and friction) that can contribute to pressure ulcer development. Shear forces are often the primary factor for pressure ulcers that develop over the sacrococcygeal area.3 The new definition also states that many variables are associated with pressure ulcer development, and we may not yet be able to identify all of them or know the significance of each variable as it relates to each pressure ulcer.
Pressure ulcer staging was initially developed in 1975.4 The intent of staging then, as now, was to identify the degree of tissue damage identifiable in the wound. However, over the years staging has been used incorrectly to determine whether the pressure ulcer has improved or has deteriorated. Currently, the Minimum Data Set (MDS) tool used in long-term care facilities requires that a pressure ulcer be back-staged or down-staged to demonstrate improvement, which is an inappropriate use of the staging system. NPUAP's 1995 statement recommended that “[r]everse staging should never be used to describe the healing of a pressure ulcer.”5 This is still a current recommendation from NPUAP
For example, once a pressure ulcer is assessed as a stage IV, it should always be documented as such. As this pressure ulcer heals by granulation, contraction, and eventually epithelialization to closure, the depth of tissue damage doesn't change. Even if the wound bed is full of granulation tissue, that tissue is not the same as what was there before injury, nor is that tissue's tensile strength the same as uninjured tissue. Even at the conclusion of the remodeling/maturation phase of wound healing, which can take many months, the repaired tissue's tensile strength is less than uninjured tissue. Therefore, complete the MDS as per instructions, but include in the narrative documentation a comment such as “This pressure ulcer currently appears to be a stage III. However, it is a granulating stage IV with the bone and muscle no longer exposed.”
The definitions of the stages were revised in important ways:
Stage I Pressure Ulcer
[A]n observable, pressure-related alteration of intact skin whose indicators as compared to the adjacent or opposite area on the body may include changes in one or more of the following: skin temperature…, tissue consistency…, and/or sensation….
The ulcer appears as a defined area of persistent redness in lightly pigmented skin, whereas in darker tones, the ulcer may appear with persistent red, blue, or purple hues.5
Intact skin with non-blanchable redness of a localized area usually over a bony prominence. Darkly pigmented skin may not have visible blanching; its color may differ from the surrounding area
Further description: The area may be painful, firm, soft, warmer or cooler as compared to adjacent tissue. Stage I may be difficult to detect in individuals with dark skin tones. May indicate “at risk” persons (a heralding sign of risk).2
This new stage I definition reinforces that the epidermis remains intact, but there is some alteration in the appearance of the skin. In persons with light skin tones, this alteration may appear as erythema that doesn't blanch. However, in individuals with dark skin tones, there may not be assessable blanching. It is important for the nurse to assess whether the patient has pain, increased firmness or softness, or change in temperature at the area of suspected ulceration when compared with surrounding tissue. For example, a resident might complain of heel pain, so the nurse blanches the skin of the heel. It blanches easily with rapid capillary refill, but the patient complains of pain at the site and the tissue feels mushy. This would be considered a stage I pressure ulcer.
Stage II Pressure Ulcer
Partial thickness skin loss involving epidermis, dermis, or both. The ulcer is superficial and presents clinically as an abrasion, blister, or shallow crater.5