Linking microvascular collapse to tissue hypoxia in a multiscale model of pressure ulcer initiation.

Linking microvascular collapse to tissue hypoxia in a multiscale model of pressure ulcer initiation. Biomech Model Mechanobiol. 2019 Jun 15;: Authors: Sree VD, Rausch MK, Tepole AB Abstract Pressure ulcers are devastating injuries that disproportionately affect the older adult population. The initiating factor of pressure ulcers is local ischemia, or lack of perfusion at the microvascular level, following tissue compression against bony prominences. In turn, lack of blood flow leads to a drop in oxygen concentration, i.e, hypoxia, that ultimately leads to cell death, tissue necrosis, and disruption of tissue continuity. Despite our qualitative understanding of the initiating mechanisms of pressure ulcers, we are lacking quantitative knowledge of the relationship between applied pressure, skin mechanical properties as well as structure, and tissue hypoxia. This gap in our understanding is, at least in part, due to the limitations of current imaging technologies that cannot simultaneously image the microvascular architecture, while quantifying tissue deformation. We overcome this limitation in our work by combining realistic microvascular geometries with appropriate mechanical constitutive models into a microscale finite element model of the skin. By solving boundary value problems on a representative volume element via the finite element method, we can predict blood volume fractions in response to physiological skin loading conditions...
Source: Biomechanics and Modeling in Mechanobiology - Category: Biomedical Science Authors: Tags: Biomech Model Mechanobiol Source Type: research