Effect of pressure and shear on skin vitality

Pressure ulcers - skin vitality - pressure - shear - blood flow
Decubitus - doorligwonden - huid vitaliteit - doorbloeding - druk - afschuiving

Pressure ulcers are a significant problem in healthcare, not only affecting the quality of life, morbidity and mortality of patients but also in terms of healthcare costs. The prevalence of pressure ulcers in healthcare institutions in the Netherlands was on average 8.3% (range 0% - 24%) in 2012. These figures are comparable with other Western countries such as UK, Canada and the USA . Most pressure ulcers in healthcare institutions in the Netherlands heal within three months, but in the home care situation almost 50% of the pressure ulcers do not heal within six months. The costs associated with pressure ulcers in the Netherlands alone is over 200 million Euros annually.
Although the exact aetiology of pressure ulcers is still under debate, there is consensus that pressure ulcers develop when tissue is devitalized. Tissue viability depends on the microcirculation for the exchange of oxygen, carbon dioxide, nutrients, water and waste products. If the microcirculation is blocked, waste products accumulate and an oxygen deficiency arises, leading to deterioration of the cells and the tissues. A few factors are directly linked to the development of pressure ulcers: immobility, mechanical loading (pressure and/or shear), moisture and ischemia. Immobility is seen as a prerequisite for the development of a pressure ulcer, and also has an effect on the mechanical load exerted on the tissue.
If loading is persistent for a longer period of time, tissue damage can occur as a direct result of internal stresses or as an indirect results of changed blood circulation.
To improve prevention of pressures ulcers, more knowledge is needed on the relation between loading on the skin and the change in blood circulation. In particular, the effect of shear on the skin microcirculation is unknown. Within this research we want to investigate the relation between pressure and/or shear and the change in circulation and whether this response changed with age of patient groups.