Elucidation of time to lead to the onset of pressure ulcers using the cells and animal experiment

皮肤组织可以看作是以组织内流动的血液为液相，胶原纤维为固相构成的固液双相粘弹性多孔材料。由于皮肤组织在经皮压力作用下得到巩固，因此定量研究孔隙度下降与血液循环障碍之间的关系具有重要意义。测量兔耳蠕变变形引起的组织固结和随后的血流变化。组织内血流顺应性CS以孔隙度P的指数函数表示，CS=345.3P-2.68（相关系数R2=0.999），发现经皮压力大于等于20 mm Hg时，组织内血流量迅速下降。为了给压疮提供高水平的安全性和生物相容性，有必要确保足够的血液流向压疮的皮肤组织。

Skin tissue can be regarded as a solid-liquid biphasic visco-elastic porous material constructed by with the blood flowing in tissues as the liquid phase and collagen fibers as the solid phase. As skin tissues are consolidated by percutaneous pressure, it is important to quantitatively study the relationship between decline in porosity and blood circulation disorder. Consolidation of tissues due to creep deformation of rabbit ears and subsequent changes in blood flow were measured. Blood flow compliance CS inside tissues is expressed as an exponential function of porosity P as CS=345.3P-2.68 (correlation coefficient R2=0.999), and it came to light that blood flood inside tissues rapidly decline under the percutaneous pressure of 20 mm Hg or more. In order to give a high level of safety and biocompatibility to pressure ulcers, it is necessary to ensure that adequate blood flows to the skin tissue, where pressure ulcers is mounted.