Do High Frequency Ultrasound Images Support Clinical Skin Assessment?

High frequency ultrasound imaging has been reported as a potential method of identifying the suspected tissue damage in patients “at risk” of pressure ulceration. The aim of this study was to explore whether ultrasound images supported the clinical skin assessment in an inpatient population through identification of subcutaneous tissue damage. Skin on the heels and/or sacral coccygeal area of fifty vascular surgery inpatients was assessed clinically by tissue viability nurses and with ultrasound pre operatively and at least every other day until discharge. Images were compared to routine clinical skin assessment outcomes. Qualitative classification of ultrasound images did not match outcomes yielded through the clinical skin assessment. Images corresponding to 16 participants were classified as subgroup 3 damage at the heels (equivalent to grade 2 pressure ulceration); clinical skin assessment rated no heels as greater than grade 1a (blanching erythema). Conversely, all images captured of the sacral coccygeal area were classified as normal; the clinical skin assessment rated two participants as grade 1b (non-blanching erythema). Ultrasound imaging is a potentially useful adjunct to the clinical skin assessment in providing information about the underlying tissue. However, further longitudinal clinical assessment is required to characterise images against actual and “staged” pressure ulceration. 1. Introduction A pressure ulcer is defined as an area of localised damage to the skin and the underlying tissue caused by prolonged mechanical loading involving a combination of pressure, shear, and/or friction [1] with costs to the individual including pain, embarrassment, social exclusion, and a reduced quality of life [2]. Financial costs to the NHS of this largely preventable condition have been estimated to range from ￡1.4 to ￡2.1 billion per annum [3]. One subset of pressure ulcers, known as deep tissue injuries, has been characterised by damage which is localised in tissues at the bone muscle fascia, and which progresses up through the tissues in the form of oedema until reaching the skin surface [4, 5]. These are not readily apparent to the eye, and thus, by the time the clinical signs of deep tissue injury are evident, the injury is often well established and its resulting prognosis is variable [6]. The need for the investigation into early detection of pressure ulcers so that timely healthcare interventions can occur has been recognised [7]. Early detection and prevention would greatly reduce the burden on the patient and the associated economic and