SKIN-BAR project: protocol for a prospective cohort study investigating skin barrier function and pressure injury development in critically ill adults.

INTRODUCTION: Pressure injuries (PIs) remain a common and costly complication among critically ill patients despite advances in prevention strategies. Current assessment methods rely primarily on visual skin inspection and risk assessment tools, which may fail to detect early physiological alterations preceding visible tissue damage. Biophysical parameters, including transepidermal water loss, stratum corneum hydration, skin pH and skin temperature, have emerged as promising indicators of skin barrier dysfunction; however, longitudinal evidence in intensive care populations remains limited. This study aims to investigate temporal changes in skin barrier function in pressure injury-prone and affected skin and to identify clinical and physiological factors associated with skin barrier dysfunction and pressure injury development. METHODS AND ANALYSIS: The SKIN-BAR project is a prospective observational cohort study to be conducted in an adult intensive care unit in Turkey. A total of 165 critically ill adults will be recruited and followed throughout their intensive care unit (ICU) stay. Skin barrier function will be assessed using non-invasive measurements of transepidermal water loss, stratum corneum hydration, skin pH and skin temperature. Measurements will be obtained within the first 4 hours of ICU admission, at 24, 48, 72 and 96 hours, on day 14, and weekly thereafter until ICU discharge. Clinical, laboratory, treatment-related and nursing care variables will also be collected. Linear mixed-effects models will be used to examine longitudinal changes in skin barrier function, while discrete-time survival analysis will be used to evaluate factors associated with incident pressure injury development. ETHICS AND DISSEMINATION: Ethical approval has been obtained from the Institutional Research Ethics Committee. Written informed consent will be obtained from participants or their legally authorised representatives before enrolment. Findings will be disseminated through publication in peer-reviewed journals, presentations at national and international scientific conferences and other academic dissemination activities. TRIAL REGISTRATION NUMBER: NCT07560683.