Researchers reported the measurement of subepidermal moisture by surface electrical capacitance can be an important tool in the assessment and prevention of pressure injuries.

They compared using the capacitance measurement with visual skin assessment of pressure ulcers at the trunk location in 417 nursing home residents residing in 19 facilities. The participants were at risk for pressure ulcers, with a mean score for Braden Scale for Predicting Pressure Ulcer Risk of 15.6.

Investigators obtained concurrent visual assessments and subepidermal moisture readings at the sacrum as well as the right and left ischium weekly for 16 weeks.

Elevated subepidermal moisture values occurred with concurrent skin damage at the sacrum, and higher subepidermal moisture values were associated with visual damage one week later.

“Subepidermal moisture of 39 tissue dielectric constant units predicted 41% of future skin damage, while visual ratings predicted 27%,” they wrote. “Thus, this method of detecting early skin damage holds promise for clinicians, especially as it is objective and equally valid for all groups of patients.”

The study results are available at:

Meanwhile, the same researchers reported on subepidermal moisture and visual skin assessment of heel pressure injury among the same study group over 16 weeks.

In those measurements, subepidermal moisture was associated with concurrent damage and damage one week later. Subepidermal moisture detected deep tissue injury and differentiated among those that resolved, remained, and deteriorated over 16 weeks.

These researchers concluded that subepidermal moisture may be an objective method for detecting heel pressure injury.