Predicting deep tissue injury pressure ulcers: a conceptual model

Pressure ulcers (PU) have been described in the literature as early as 2050–100BC and were first identified in Egyptian mummies.¹ According to Shea,² PUs were described in writings of Fabricus, a surgeon from the Netherlands, and Charcot, a French neurologist and pathologist. Indeed, in 1860 Florence Nightingale wrote:

‘… if he has a bedsore, it is generally the fault not of the disease, but of the nursing’.^3’

In 1955, Guttman⁴ devised the first classification system for PUs. However, most importantly, a closed PU and four different stages of soft tissue injury was described by Shea.²

The term deep tissue injury (DTI) was introduced as a classification in 2002.⁵ DTIs appear with intact skin with differing shades of purple hue. This type of PU can deteriorate quickly, within hours to days, depending on the amount of tissue damage present. However, DTIs are difficult to identify in patients with dark skin tone. If you look at Fig 1, there are two pictures of a patient with a light skin tone and a patient with a dark skin tone for comparison. The centre of the DTI reveals black necrotic tissue as the extent of the tissue damage becomes apparent.