Temperature modulation of skin tolerance to applied mechanical loading and shear

Pressure ulcers (PUs) are a localised damage to the skin resulting from prolonged periods of pressure and shear when lying, sitting, or wearing a medical device such as a face mask. PUs can affect any individual, particularly those who experience prolonged immobility due to hospitalisation, ranging from babies to elderly adults. PUs worsen people's quality of life and they are also very costly to healthcare providers such as the NHS. Indeed, in the UK, the annual cost of treating skin wounds, including PUs, has been estimated to be approximately £8.3 billion a year. Accordingly, improving our understanding of how the human skin respond to pressure could lead to the development of cost-effective, personalised solutions to maintain skin health.

Cooling the skin is a promising approach to increase the skin's resilience to damage induced by prolonged periods of pressure (e.g. when one is bedridden) or repeated rubbing against a hard surface (i.e. shear stress). Early animal studies showed that cooling the skin reduces the risk of developing a PU, and this has been more recently confirmed in preliminary human studies. Yet, we still do not know enough about why and how cooling makes the skin more resilient to pressure and shear. Furthermore, cooling the skin can be uncomfortable and this can limit how acceptable the therapy is, particularly amongst vulnerable people at risk of developing PUs such as the elderly and those with a spinal cord injury. This knowledge gap raises a series of basic biological questions, which have clear implications for the prevention of PUs, and for the development of new devices that control skin temperature and help maintaining skin health across the life course. These questions are:

- How does cooling change the vascular, immunological, structural, and perceptual responses of the skin to a mechanical insult?
- Do the responses to cooling change with ageing and with the presence of a spinal cord injury, both of which increase the risk of...