A 5-Year Retrospective Study of Descriptors Associated With Identification of Stage I and Suspected Deep Tissue Pressure Ulcers in Persons with Darkly Pigmented Skin

Background. As skin assessment is critical to pressure ulcer prevention, it is essential that practitioners performing skin assessments understand individuals with dark skin tones may represent at-risk persons. In addition, visual cues commonly associated with the identification of stage I and suspected deep tissue injury (sDTI) pressure ulcers may not be sufficient in persons with darkly pigmented skin. Objective. The purpose of this study was to identify common descriptors associated with stage I and sDTI pressure ulcers in persons with darkly pigmented skin, to determine whether the National Pressure Ulcer Advisory Panel (NPUAP) definitions are adequate, and to identify additional descriptors that might aid practitioners in identifying pressure ulcers in this at-risk population. Methods. A 5-year retrospective review of 96 subjects with 274 stage I or sDTI pressure ulcers was conducted at an acute care facility. A literature search aided in identifying descriptors associated with pressure ulcers in persons with darkly pigmented skin. Computer-queried records targeted subjects matching the descriptors of “African American,” “Asian,” “Hispanic,” “American Indian,” “Alaskan Native,”“Native Hawaiian,” or “Pacific Islander” descent; with a “stage I or sDTI” and a “WOCN consult” from “March-2008 through March-2013.” The pressure ulcer documentation of 9 wound, ostomy, and continence nurses (WOCNs) was analyzed. Results. Stage I and sDTIs presentations were varied. However, the majority of pressure ulcers were associated with descriptors consistent with NPUAP staging guidelines. For stage I pressure ulcers, the prevailing presentation was nonblanchable erythema in 66 (75%) cases and intact skin in all 88 (100%) cases. Contrary to NPUAP guidelines, the blanching effect was commonly present. Stage I pressure ulcers also presented with normal color in 17 (11.4%) instances and were accompanied by bogginess, pain, and induration. For sDTI pressure ulcers, the prevailing color presentation was purple discoloration in 130 (70%) of the 186 cases. Intact skin was observed in 140 (75.3%) cases of the 186 cases. Conclusion. Contrary to NPUAP guidelines, this study showed sDTIs can have a break in the skin, with 26 (14%) ulcers demonstrating this. This suggests the NPUAP definition may benefit from revision to improve the accuracy of sDTI identification among persons with darkly pigmented skin.

 Assessment of the skin is critical to the prevention of pressure ulcers. It is important that skin assessment be completed by trained practitioners who are aware of the presentation differences between light and darkly pigmented skin, and that individuals with dark skin tones may represent at-risk persons.¹ In this at-risk population, visual cues commonly associated with the identification of stage I and suspected deep tissue injury (sDTI) pressure ulcers may not be sufficient for pressure ulcer recognition. Consequently, failure to assess the skin adequately and to detect skin changes early may lead to the development of severe pressure ulcers and/or life threatening complications.

  Stage I and sDTI pressure ulcers have been traditionally more difficult to identify in patients with darkly pigmented skin because clinicians primarily rely on visual cues that may be absent or present differently in persons with darkly pigmented skin. The National Pressure Ulcer Advisory Panel (NPUAP) describes a stage I pressure ulcer as “intact skin with nonblanchable redness of a localized area usually over a bony prominence” and a sDTI pressure ulcer as a “purple or maroon localized area of discolored intact skin or blood-filled blister due to damage of underlying soft tissue from pressure and/or shear.”¹

  Any variations in skin pigmentation can obscure the first signs of pressure-related skin damage. The Fitzpatrick Classification Scale was developed in 1975 by Harvard Medical School Dermatologist Thomas Fitzpatrick, MD, PhD. Though this scale classifies a person’s complexion and their tolerance to sunlight, Dr. Fitzpatrick determined that darker skin is typically oilier and thicker. Black skin, classified as Fitzpatrick type VI, is prone to hyperkeratosis (ie, excessive cell turnover and dead skin buildup), pigmentation disorders, and keloid scarring. Also, Asian skin, classified as Fitzpatrick type IV, has a tendency to become hyperpigmented.²

  The NPUAP guidelines, which influence how health care practitioners assess the skin, utilize visual and tactile cues to identify pressure-related skin changes.¹ These pressure-related skin changes, though easily observed in white or lightly pigmented skin (Fitzpatrick I-II), may be more difficult to detect in darkly pigmented skin. A diversity of skin tones coupled with the various skin changes common among patients with darkly pigmented skin further complicates the identification of pressure ulcers in ethnic groups represented within this at-risk population. It is for these reasons that guidelines focused on the use of visual cues for pressure ulcer recognition may put patients with darker skin pigmentation at a disadvantage when it comes to diagnosis.

  The presence of nonblanchable erythema is a risk factor for the development of more severe forms of pressure damage.^3,4 The challenge in recognizing nonblanchable redness in darkly pigmented skin may help to explain why black patients are more likely to have stage 2-4 pressure ulcers than white patients.³ One study by Rosen et al³ suggested the failure to identify early stages of pressure damage resulted in greater numbers of severe pressure ulcers in patients with darkly pigmented skin. This information is supported by the NPUAP specifications that for patients with darkly pigmented skin, visual blanching may be absent and variable coloration may present in patients with stage I pressure ulcers and detection of deep tissue injury pressure ulcers may be challenging.¹ There is further clarification that for both stage I pressure ulcers and sDTI, pressure-related skin damage may present as “painful, firm, soft, warmer, or cooler as compared to adjacent tissue.”¹

  Early identification of risk factors is an essential component of preventing pressure ulcers and the adverse outcomes associated with them. Pressure ulcers are associated with exorbitant costs, pain, impeded return to full functioning, extended length of stay, sepsis, and increased mortality. The average cost in the United States to treat an individual with a sDTI pressure ulcer is estimated to be $43,180 but can easily exceed $100,000 if that ulcer progresses to stage III or stage IV.⁵ The annual cost of pressure ulcers in the United States ranges from $9.1 billion to $11.6 billion.^5,6 The length of hospitalizations for pressure ulcers is nearly 3 times longer than hospitalizations without a pressure ulcer diagnosis and nearly 60,000 US hospital patients die each year from complications due to hospital-acquired pressure ulcers.⁴ In addition, patients who develop a hospital-acquired pressure ulcer are more likely to die in the hospital or within 30 days after discharge and are more likely to be readmitted within 30 days following discharge.⁶

  Beyond the emotional, financial, and medical consequences for patients who develop severe pressure ulcers, there may be regulatory, legal, and financial implications for health care providers and health organizations. Pressure ulcers are the second most common wrongful death claim and result in more than 17,000 lawsuits per year in the United States.,4

  In October 2008, the Centers for Medicare and Medicaid Services (CMS) halted reimbursement to hospitals for hospital-acquired stage III and stage IV pressure ulcers. The CMS does, however, allow for increased reimbursement for stage III and stage IV pressure ulcers that were present on admission. Therefore, early recognition of pressure damage, especially on admission to a health facility is essential to accessing available reimbursement.

  In February 2013, the NPUAP held an international sDTI consensus conference to develop a consensus among the wound care community regarding the assessment of sDTI in patients with darkly pigmented skin. Unfortunately, after much debate, no consensus was achieved and the question was ultimately tabled for future discussion, but the wound care community was challenged to seek out the answers to this difficult question.

  This research was completed in response to that charge with the primary goal of increasing the knowledge and effectiveness of practitioners actively involved in the care of patients with darkly pigmented skin by contributing to the limited body of evidence surrounding assessment of pressure-related skin damage in this patient population. Ultimately, an increased knowledge of the common presentations of pressure-related skin damage among this at-risk population will improve patient outcomes.

A literature search was performed to better understand clinical presentation of stage I and sDTI pressure ulcers in patients with darkly pigmented skin and to prevent the duplication of evidence. A research request was generated with key words from the PICO question (ie, population, intervention, comparison, and outcome); “In adult, hospitalized patients with darkly pigmented skin with stage I and suspected deep tissue injury sacral pressure ulcers, which common descriptors exist that clearly delineate pressure related skin changes?” Specific keywords utilized in the search included “pressure ulcer,” “skin assessment,” “stage I,” “suspected deep tissue injury,” and “dark pigmented skin.”

  A total of 36 sources related to pressure ulcers in dark skin were identified through a literature search of SCOPUS (8), CINAHL (9), and OVID MEDLINE (19). All abstracts and guidelines were assessed for relevance to the research question by the primary investigator (PI), who is credentialed through the Wound, Ostomy, and Continence Nurses (WOCN) Society Certification Board as a certified WOCN. Articles not relevant to the research question or to the descriptors associated with pressure-related skin damage in adult hospitalized patients with darkly pigmented skin were excluded. The majority of the sources (29) were excluded because they focused on the use of technology for the identification of pressure ulcers in dark skin. Two other sources were excluded because they addressed economic disparities in accessing care instead of the physical assessment of pressure-related skin changes in darkly pigmented skin. Five sources addressed visual and/or tactile pressure-associated skin changes in persons with darkly pigmented skin.^7-11 All 5 included articles were reviewed in detail, and relevant information abstracted.

  Four of the five articles focused on African-American skin, which excluded the myriad of ethnic groups also presenting with darkly pigmented skin. These ethnic groups may offer important information into the full range of descriptors used to identify early pressure-related changes in dark skin. In an attempt to broaden the focus beyond 1 ethnic group, a second search was generated to include patients of Asian, Hispanic, American Indian, Alaska Native, and Native Hawaiian or Other Pacific Islander descent. No time frame was specified for the second search, which yielded 3 additional sources.^12-14

  Of the 8 sources ultimately included, descriptors were identified in several areas of the skin assessment. These descriptors were used as the foundation for data collection. Color descriptors presented in the literature (n = 8) included blue (8, 100%), purple (7, 87.5%), erythema and discoloration (4, 50%), nonblanching (3, 37.5%), maroon and blanched (2, 25%), pale and black (1, 12.5%), and gray (0, 0%). Temperature descriptors represented in the literature included warm 8 (100%), and cool 4 (50%). Moisture descriptors included maceration 1 (12.5%). The literature also showed that pressure-related skin changes in people with darkly pigmented skin may present as texture and turgor changes including edema and induration (7, 87.5%); tense or taut (2, 25%); and boggy, soft, shiny, or hard (1, 12.5%). Skin integrity associated with pressure-related skin changes as represented in the literature included intact (1, 12.5%) and open (1, 12.5%). Other descriptors represented in the literature included pain (3, 37.5%) and blisters (2. 25%). Despite a variety of documented assessment findings with several commonalities among the sources, no consensus or established guideline was elucidated for this unique patient population. This is the first study that looks at multiple ethnicities with darkly pigmented skin and seeks to identify common presentations of pressure-related skin damage in this at-risk population.

A 5-year retrospective review of medical records from March 2008 to March 2013 of patients at the Mayo Clinic, Jacksonville, Florida was undertaken. Study procedures were approved by the Institutional Review Board and the Evidence-Based Practice (EBP) Nursing Research Council at the Mayo Clinic. The study setting was an acute care health facility where WOC nurses perform consultative services for patients with pressure ulcers.

  Participants. Inclusion criteria were hospitalized patients, 18 years or older, with a stage I or sDTI pressure ulcer confirmed by the WOC nurse. A single-site report request was submitted to the information technology department detailing the inclusion criteria as follows: “patients hospitalized between March 1, 2008 and March 31, 2013” with a “stage I or suspected deep tissue injury pressure ulcer” and a “WOCN consult” who were of African American, Asian, Hispanic, American Indian, Alaskan Native, Native Hawaiian, or Pacific Islander descent. Exclusionary criteria included patients who were white; patients with a stage II, stage III, stage IV, or unstageable pressure ulcer; or patients without a pressure ulcer.

  Procedure. The initial report generated 1803 records. An initial screen of the records revealed that 117 records contained information outside of the March 2008 to March 2013 timeframe. A second report request was submitted to the information technology department with the research criteria for subjects “hospitalized during March 1, 2008 through March 31, 2013” and of “African American, Asian, Hispanic, American Indian, Alaskan Native, Native Hawaiian, or Pacific Islander” descent, with a “stage I or suspected deep tissue injury pressure ulcer” and a “WOC consult.” This second report yielded 1182 records. After the removal of duplicates, an initial sample size of 927 was achieved. This computer-generated sample was reviewed based on study inclusion and exclusion criteria.

  Data collection. The data collection tool was developed by the PI and validated through consensus by the Institutional EBP Nursing Research Council. The EBP Nursing Research Council assisted with ensuring the completeness of the literature review. Research goals and timelines were discussed and revised as needed.

  Nine registered nurses with varying degrees, training, and experience contributed to the data. Eight of the contributing nurses were certified in the wound care field by the Wound, Ostomy, and Continence Nurses Society, and the 1 nurse not certified had more than 5 years experience in wound care practice. Data were collected using the standardized chart review form developed by the primary researcher. Abstracted data included ethnicity, the presence of a pressure ulcer, ulcer site, whether that pressure ulcer was a stage I or sDTI, and all descriptors associated with each stage I and sDTI pressure ulcer. Each subject was assigned a number for anonymity and all protected health information was de-identified.

  All data were entered into an Excel spreadsheet and analyzed by the PI. The PI evaluated each WOCN’s pressure ulcer documentation individually to identify descriptors associated with each stage I and/or sDTI pressure ulcer at each encounter. The descriptors were categorized according to stage as stage I and sDTI pressure ulcers have specific guidelines for identification according to the NPUAP. The wound, ostomy, and continence nurses’ documentation was used in lieu of the nursing assessments to increase the probability that skin changes that are normal among persons with darkly pigmented skin, such as hyperpigmentation, would be clearly distinguished from pressure-related skin changes. Not all ulcers were assessed during each WOCN encounter but all pressure ulcer descriptors used at each encounter were recorded for further analysis.

  Data analysis. Descriptive statistics were used to summarize continuous variables such as ethnic descent and ulcer descriptors. This is represented in the raw data. Trends and frequencies are shown in percentages.

The final sample size included 96 subjects with 274 stage I or sDTI pressure ulcers (Tables 1 and 2). There were 40.6% (39) subjects with stage I pressure ulcers and 59.4% (57) with sDTI pressure ulcers. Of the 96 subjects, the majority were identified as African American, accounting for 30 (76.9%) stage I pressure ulcers and 50 (87.7%) sDTI pressure ulcers. Subjects identified as being of Asian descent accounted for 7 (18%) stage I pressure ulcers and 5 (8.8%) sDTI pressure ulcers. Subjects identified as being of Indian or Middle Eastern descent accounted for 2 (5.1%) stage I pressure ulcers and 2 (3.5%) sDTI pressure ulcers. Though several other ethnicities with darkly pigmented skin—Latino/Hispanic, biracial, and Native Hawaiian/Pacific Islander—were anticipated, no stage I or sDTI pressure ulcers were found among these populations.

  Among the 274 stage I or sDTI pressure ulcers, 88 (32.2%) were stage I and 186 (67.8%) were sDTI. Of the stage I pressure ulcers, 42 (47.7%) were heel ulcers, followed by 16 (18%) foot ulcers, 8 (9.2%) hip ulcers, 8 (9.2%) sacral ulcers, and 3 (3.4%) ischial ulcers. Rib, buttock, knee, and spine ulcers each accounted for 2 (2.3%) of the stage I pressure ulcers, while the coccyx, leg, and shoulder each accounted for 1 (0.1%) of the total stage I pressure ulcers. The primary site for sDTI pressure ulcers was the heel with 96 (51.6%), followed by 30 (16.1%) sacrum ulcers, 24 (12.9%) foot ulcers, 11 (6%) hip ulcers, 6 (3.1%) achilles ulcers, and 4 (2.2%) spine ulcers. Buttock, knee, leg, shoulder, ankle, and forehead ulcers each accounted for 2 (1.1%) of the total sDTI pressure ulcers. Ischium, coccyx, and abdominal ulcers each represented 1 (0.5%) of the total sDTI pressure ulcers.

  Stage I pressure ulcers presented in various manners in patients with darkly pigmented skin. The majority of these pressure ulcer descriptors align with the NPUAP stage I pressure ulcer definition of nonblanchable redness of intact skin. Specifically, 66 (75%) ulcers presented with erythema or redness, 66 (75%) were nonblanchable, and 88 (100%) of the ulcers had intact skin. The presence or absence of blanching was not documented in 20 (22.7%) of the 88 ulcers. The 66 ulcers with nonblanchable redness of intact skin were also accompanied by hyperpigmentation in 9 (14%) ulcers, dark red discoloration in 3 (4.7%), persistent blanching in 2 (2.3%), and dusky discoloration in 1 (1.5%).

  Conversely, 17 (11.4%) of the stage I pressure ulcers in patients with darkly pigmented skin presented with normal color. However, these 17 ulcers were also accompanied by tissue that was boggy (14, 82.4%), painful (3, 17.6%), and indurated (1, 5.9%). Additionally, 5 of these ulcers were both hyperpigmented and boggy. Of mention, all 14 of the ulcers where bogginess was documented were heel ulcers. No temperature alterations, including warmth or coolness, were noted among the sample population with stage I pressure ulcers (Tables 3 and 4).

  Like the previously discussed stage I pressure ulcers in darkly pigmented skin, sDTI pressure ulcers offered an even larger variation in presentation. However, the majority of sDTI pressure ulcers presented with descriptions similar to the NPUAP staging guideline of “purple or maroon localized area of discolored intact skin or blood-filled blister.” With regard to color, 130 (70%) sDTI pressure ulcers presented with purple discoloration. Surprisingly, the second most common color presentation was gray discoloration (26,14%), followed by black (20, 10.8%), brown (17, 9.1%), blue (11, 5.9%), and maroon (10, 5.4%). Additional color presentations included redness (5, 2.6%) and pink discoloration (2, 1%) but were components of ulcers where there was prevailing purple discoloration. With regard to intactness, 140 (75.3%) of the sDTI pressure ulcers had intact skin and 20 (10.8%) were comprised of a fluid-filled blister. However, the remaining 26 (14%) sDTIs had an open area or a break in the skin.

  Additional descriptors included discoloration, which was documented for 114 (61.3%) ulcers; dark was used 23 (12.4%) times; hyperpigmented, 21 (11.3%) times; nonblanchable, 9 (4.8%) times; and purple discoloration accompanied by persistent blanching, 1 (0.5%) time. The absence of blanching was documented 9 times (4.8%). No temperature alterations were noted among the sample population with sDTI pressure ulcers. Turgor was described using 7 terms: boggy (19, 10.2%), serum fluid-filled (18, 9.7%), indurated (3, 1.6%), soft (3, 1.6%), blood blister (2, 1.1%), edema (1, 1.6%), and fluctuant (1, 1.6%). Pain was documented 4 (2.2%) times.

  Thirty-one sDTI ulcers involved descriptors associated with various levels of tissue damage; 17 (54.8%) of these were described as having partial-thickness skin loss; 13 (41.9%) had red tissue documented, and 6 (19.4%) had pink tissue documented. Sixteen of the 31 (51.6%) ulcers had eschar necrosis and 3 (9.7%) had slough. Six (19.4%) ulcers had desquamation documented, 2 (6.5%) were documented as denuded, and 1 (3.2%) was described as pale (Table 4).

Though the NPUAP has recognized that pressure ulcers, specifically stage I and sDTI, may present differently in patients with darkly pigmented skin, there is minimal evidence that validates common presentations in this at-risk population. There is even less research to validate the definitions or to help clinicians understand how to best identify these levels of tissue damage in patients with darkly pigmented skin. The purpose of this study was to identify common descriptors associated with pressure-related skin changes in persons with darkly pigmented skin, with a particular focus on stage I and sDTI pressure ulcers. In addition, the researcher sought to uncover whether the NPUAP definitions for stage I and sDTI are adequate and, if not, what other assessment findings might be useful in identifying pressure-related skin damage in persons with darkly pigmented skin.

  For stage I pressure ulcers in patients with darkly pigmented skin, nonblanchable redness of intact skin was the prevailing presentation. This study suggests the blanching effect is common and should be assessed in patients with darkly pigmented skin. However, these assessments require good lighting and possibly closer observation as suggested in the literature.⁹ In the absence of redness and/or blanching, the assessing practitioner should look for other signs of tissue damage such as bogginess, pain, or persistently blanched discoloration. For stage I pressure ulcer, bogginess is common, even in the absence of redness. Pain may be an indicator of early pressure-related tissue damage, even in the absence of redness. Hyperpigmentation is common and does not necessarily obscure the presence of redness. This study suggests that it may, in fact, be an indicator of early tissue damage.

  For sDTI pressure ulcers in patients with darkly pigmented skin, purple discoloration of intact skin was the prevailing presentation followed by purple fluid-filled areas or blood blisters. This is in alignment with NPUAP pressure ulcer staging guidelines¹; however, in this population, purple discoloration is often accompanied by bogginess and/or pain. Another observation was that sDTIs can have a break in the skin even when the ulcer is still primarily comprised of purple discoloration. In this study, these breaks in the skin presented as partial-thickness skin loss (stage II), desquamation, denudement, eschar, and slough. Desquamation and denudement commonly suggest an underlying moisture component, but the presence of partial-thickness skin loss or a stage II within the purple discoloration is perplexing. The current NPUAP definition suggests that sDTIs must have intact skin¹ but makes no accommodations for the ulcer that is predominantly purple but has a break in the skin. This guideline is further convoluted when that break reveals red or pink partial-thickness skin loss or a stage II within the purple discoloration. A break in the skin exposing the dermal layer that is surrounded by purple discoloration (Figure 1), calls into question whether deep tissue injury has truly occurred, whether the tissue is being recovered, and how much of the ulcer will progress to full-thickness tissue loss, if any. The current literature reviewed for the purposes of this study, including the staging guidelines, leave this to each practitioner’s experience and to facility and regulatory agency guidelines. This suggests that the definition for sDTI may need revision to include insight into the possibility of sDTIs having a break in the skin, guidance into what sDTIs with dermal exposure should be called, and insight into when the sDTI label should transition to another stage.

The single site, relatively small sample size, and study design limit the ability to generalize findings to all patients with stage I and sDTI pressure ulcers. The WOCN assessment of the ulcers was completed primarily after the ulcer was identified by the general nursing staff and a consult was generated. Therefore, the impact of potentially delayed identification cannot be elucidated. The variability of descriptors may be a limitation as each WOCN, though part of a team, is an independent practitioner with varied experience, training, and skill. The shorter length of stay for acute care patients limited the degree to which follow-up encounters were available. The study endpoint was limited by the length of stay and/or the degree to which WOCN assessments were available.

  The purpose of this study was to first identify common descriptors associated with stage I and sDTI pressure ulcers in persons with darkly pigmented skin. Additionally, the aim was to ascertain whether the pressure ulcer staging definitions for stage I and sDTI are adequate or need revision to adequately assist health care providers with identifying pressure-related skin damage in this population. The data showed that the majority of stage I and sDTI pressure ulcers will present according to NPUAP pressure ulcer guidelines. However, these assessments should be bolstered with attention to identifying other alterations in the skin that are common in patients with darkly pigmented skin. This study also suggests that the pressure ulcer staging definitions do not cover the full gamut of presentations in clinical practice, and practitioners must use the guidelines as a foundation for assessment augmented by their experience and training to appropriately identify stage I and sDTI pressure ulcers in patients with darkly pigmented skin. Further research is needed to clearly define best practice for early pressure ulcer identification and intervention, to clearly delineate the incidence of clinical presentations not addressed by the current staging guideline, and to determine which descriptors will be most effective and inclusive for persons with darkly pigmented skin. This may aid clinicians in better identifying pressure ulcers with the magnitude for early intervention, tissue recovery, and to demonstrate sDTI incidence and all patterns of evolution as a justification for increased reimbursement, when appropriate.

Affiliation: Mayo Clinic, Jacksonville, FL.

Correspondence:
Rhonda Sullivan, PhD, RN, CWON, LNCC
Mayo Clinic
4500 San Pablo Road
Jacksonville, FL 32224
sullivan.rhonda@mayo.edu

Disclosure: The authors disclose no financial or other conflicts of interest.