SEM an early indicator of pressure injuries

What are the current challenges of risk assessment tools used in pressure injury prevention?

Jonathan Busby: Risk assessment tools [RATs] and a visual skin and tissue assessment [STA] by the clinician, to assess for early signs of skin damage, have been the standard of care for many years, with over 200 risk assessment tools currently available to clinicians. Despite this, many of the RATs in clinical use are reported to have low predictive value. STAs also lack reliability, and are based upon the subjective interpretation of the individual who is assessing the skin.

One major deficiency with the current risk assessment processes is that they do not alert the clinician to the biological changes that occur beneath the skin surface. Tissue changes may occur beneath the observable skin level days before tissue breakdown and ulceration is visible at the surface. The tissue changes that may lead to pressure injury development are caused by inflammation, triggered by prolonged pressure, shear forces, tissue deformation and ischaemia. The inflammation is stimulated over time, varying from minutes to hours, and leads to a number of pathological changes.

What are the early signs of tissue damage leading to pressure injuries?

One early change is the increased permeability of blood vessels, which allows leakage of fluid from the vessels into the extracellular space. The leaked fluid accumulates as localised oedema, also known as sub-epidermal moisture [SEM], and is, therefore, an early sign that tissue damage is happening that may lead to pressure injury development. This highlights the importance of early identification and the need for early intervention in pressure injury prevention.

SEM is a biophysical marker for possible pressure injury formation in at-risk patients. The presence of SEM above a defined threshold allows prevention strategies to be implemented even before visible damage, increasing the likelihood of success in preventing pressure injuries as recognised and referenced in the updated International Clinical Practice Guidelines for pressure injury prevention and treatment.

An innovative and clinically proven technology, the Provizio SEM Scanner, provides an assessment of SEM content as an early indicator of pressure injury risk, and is increasingly being adopted into clinical practice.

In a practical sense, how can this technology make a difference in pressure injury prevention pathways?

In comparison with STA, the Provizio SEM Scanner supports clinicians in identifying specific anatomical areas – the heels and sacrum are at increased risk of pressure injury development on admission, and five days earlier than visual skin assessment, regardless of skin tone.

It identifies increased risk of pressure injury, and provides insight to the clinician that a patient without visible external signs of tissue damage is at risk of pressure injury development on the heel or sacrum. The Provizio SEM Scanner has been demonstrated as an effective tool supporting the prevention of pressure injuries when used as an adjunct to standard-of-care, with a weighted average reduction in pressure injury incidence of 90.5% in acute care facilities. Economic modelling studies based on a conservative range of assumptions also suggest that the implementation of the SEM technology, as part of a prevention protocol are a dominant strategy compared with standardof- care, since it lowers cost and increases quality-adjusted life years.

Arjo has over 60 years’ experience creating solutions for patients with mobilityrelated challenges, and by combining early identification with targeted intervention, a new approach to winning the fight against pressure injuries is now being implemented at care facilities around the world.