The skin is often referred to as the mirror of a person's health. As health care professionals, we are trained in the art of using alterations in skin color and deviations from an individual's normal skin tone to aid in our diagnoses. We all know, for example, that yellow jaundice is a sign of a liver disorder such as hepatitis or cirrhosis, that pink and blue skin changes are associated with pulmonary disease, that ashen or gray color signals cardiac disease, and that copper skin tone indicates Addison's disease, to name a few. As skin and wound care professionals, we are also acquainted with the nonblanchable erythema response in patients with a Stage I pressure ulcer (PrU), the sentinel of a developing PrU.
These clinical constructs have served us with a reasonable degree of clinical sensitivity and specificity in the majority of our patients. However, let us keep in mind that the majority of our patients-and the majority of subjects of research investigations-have light skin. We can use alterations in skin color as potential signals of pathology in these individuals because we can visualize changes such as the increased blood flow (erythema) that signals the inflammation associated with a nascent PrU.
In the Minority
What about the minority of patients we serve-those with darkly pigmented skin? How can we overcome the challenges associated with diagnosing an impending PrU in these individuals?
Finding a way to solve this complex problem is becoming urgent: We are beginning to experience a shift in our racial and ethnic demographic in the United States, which means we are likely to see more patients with darkly pigmented skin in the coming years. The literature confirms what we already know intuitively: that we are not doing a good job of detecting and reducing PrU risk in persons with darkly pigmented skin. According to recent studies, these individuals are at higher risk for developing more severe PrUs and associated mortality and morbidly, perhaps because we lack a means to make an early diagnosis of skin in danger of breaking down.
Beneath the Surface
What this tells us is that we need more sophisticated methods of looking into the skin of our patients with darkly pigmented skin so that we can appropriately diagnose and prevent their chronic wounds.
Researchers are working to provide us with those methods. Testing is currently under way on a variety of devices that could be used to detect and diagnose-regardless of skin color-alterations in blood flow and other changes that are specific to ischemia and reperfusion injury associated with the development of chronic wounds. These include visible and near-infrared spectroscopy, pulse oximetry, laser Doppler, and ultrasound.
Each of these methods infers clinical parameters associated with hemoglobin concentration and blood flow. Combining such physiologic measures with other clinical information would allow skin and wound care professionals a high degree of sensitivity and specificity in preventing, diagnosing, and treating impending chronic wounds in patients with any skin color.
Our patients should not go undiagnosed because of the color of their skin. We need to support researchers and clinicians to continue in their quest to develop methods to evaluate the potential for wound development in persons of all skin colors. I congratulate and encourage the authors of the papers listed in the Selected References of this article for their work toward achieving this goal.
Sowa MG, Matas A, Schattka BJ, Mantsch HH. Spectroscopic assessment of cutaneous hemodynamics in the presence of high epidermal melanin concentration. Clin Chim Acta 2002; 317:203-12.Matas A, Sowa M G, Taylor V, Taylor G, Schattka B J, Mantsch H H. Eliminating the issue of skin color in assessment of the blanch response. Adv Skin Wound Care 2001; 14:180-8. Lyder CH, Yu C, Emerling J, Mangat R, Stevenson D, Empleo-Frazier O, McKay J. The Braden scale for pressure ulcer risk: evaluating the predictive validity in black and Latino/Hispanic elders. Appl Nurs Res 1999; 12:60-8.Henderson CT, Ayello EA, Sussman C, Leiby DM, Bennett MA, Dungog EF, Sprigle S, Woodruff L. Draft definition of stage I pressure ulcers: inclusion of persons with darkly pigmented skin. NPUAP Task Force on Stage I Definition and Darkly Pigmented Skin. Adv Wound Care 1997; 10 ( 5 ): 16-9.Flanagan M. How can you accurately assess pressure damage on patients with darkly pigmented skins? J Wound Care 1996; 5:454.