Skin alterations of intact skin and risk factors associated with pressure ulcer development in surgical patients: A cohort study

Background The pathology literature suggests three types of pressure ulcer with six possible mechanisms leading to tissue breakdown. A limitation of current evidence is the difficulty in replicating the clinical situation and in determining the point at which a tissue assault becomes irreversible and results in tissue breakdown. In particular clinical observations of alteration in darkly pigmented skin, blanching erythema, non-blanching erythema and non-blanching erythema with other skin changes including induration, oedema, pain, warmth or discolouration have not been assessed in relation to subsequent skin/tissue loss and their pathophysiological and aetiological importance is not fully understood. Objectives To assess the validity of clinical signs of erythema as predictors of pressure ulcer development and identify variables which independently are predictive of Grade 2 pressure ulcer development. Design Prospective cohort study. Participants 109 general, vascular and orthopaedic hospital patients, aged over 55 years with an expected length of stay of 5 days were recruited. Of these 97 were pressure ulcer free at baseline and/or had complete follow-up including 59 women and 38 men with a median age of 75 years (range 55–95). Setting Single centre large acute UK NHS hospital. Methods To identify clinical signs of erythema predictive of skin loss, the odds of pressure ulcer development were examined using logistic regression. To identify variables independently predictive of Grade 2 pressure ulcer development logistic regression modeling was undertaken. Results There was significantly increased odds of pressure ulcer development associated with non-blanching erythema (7.98, p=0.002) and non-blanching erythema with other skin changes (9.17, p=0.035). Logistic regression modeling identified non-blanching erythema, pre-operative albumin, weight loss, and intra-operative minimum diastolic blood pressure, as independent predictors of Grade 2 pressure ulcer development. Conclusions Non-blanching erythema with or without other skin changes is distinct from normal skin/blanching erythema and is associated with subsequent pressure ulcer development.